Dawn change to enable writeBuffer for size != multiple of 4

Co-authored-by: Andy Hovingh <6198728+AndyHovingh@users.noreply.github.com>

.github/actions/dep-versions/action.yml

@@ -0,0 +1,7 @@
+name: 'Set up dependency versions'
+runs:
+  using: "composite"
+  steps:
+    - name: Set up dependency versions
+      shell: bash    
+      run: cat ./build/common/versions >> $GITHUB_ENV

.github/actions/linux-prereq/action.yml

@@ -0,0 +1,38 @@
+name: 'Linux Preqrequisites'
+runs:
+  using: "composite"
+  steps:
+    - uses: ./.github/actions/dep-versions
+    - name: Install Linux Prerequisites
+      shell: bash
+      run: |
+        set -xe
+        # See https://askubuntu.com/questions/272248/processing-triggers-for-man-db/1476024#1476024
+        echo "set man-db/auto-update false" | sudo debconf-communicate
+        sudo dpkg-reconfigure man-db
+
+        # Install ninja
+        source ./build/common/get-ninja.sh
+
+        # Install CMake
+        mkdir -p cmake
+        cd cmake
+
+        sudo wget https://github.com/Kitware/CMake/releases/download/v$GITHUB_CMAKE_VERSION/cmake-$GITHUB_CMAKE_VERSION-Linux-x86_64.sh
+        sudo chmod +x ./cmake-$GITHUB_CMAKE_VERSION-Linux-x86_64.sh
+        sudo ./cmake-$GITHUB_CMAKE_VERSION-Linux-x86_64.sh --skip-license > /dev/null
+        sudo update-alternatives --install /usr/bin/cmake cmake $(pwd)/bin/cmake 1000 --force
+
+        cd ..
+
+        sudo wget -O - https://apt.llvm.org/llvm-snapshot.gpg.key | sudo apt-key add -
+        sudo apt-get update
+        sudo apt-get install clang-$GITHUB_CLANG_VERSION libc++-$GITHUB_CLANG_VERSION-dev libc++abi-$GITHUB_CLANG_VERSION-dev
+        sudo apt-get install mesa-common-dev libxi-dev libxxf86vm-dev
+
+        # For dawn
+        sudo apt-get install libxrandr-dev libxinerama-dev libxcursor-dev libxi-dev libx11-xcb-dev
+
+        sudo update-alternatives --install /usr/bin/cc cc /usr/bin/clang-${GITHUB_CLANG_VERSION} 100
+        sudo update-alternatives --install /usr/bin/c++ c++ /usr/bin/clang++-${GITHUB_CLANG_VERSION} 100
+        set +xe

.github/actions/mac-prereq/action.yml

@@ -0,0 +1,23 @@
+name: 'Mac Preqrequisites'
+runs:
+  using: "composite"
+  steps:
+    - uses: ./.github/actions/dep-versions
+    - name: Set up Homebrew
+      id: set-up-homebrew
+      uses: Homebrew/actions/setup-homebrew@master
+    - name: Set up Python
+      uses: actions/setup-python@v5
+      with:
+        python-version: '3.x'
+    - name: Cache Brew
+      id: brew-cache
+      uses: actions/cache@v4 # Use a specific version
+      with:
+        path: $HOME/Library/Caches/Homebrew
+        key: ${{ runner.os }}-brew-20250424
+    - name: Install Mac Prerequisites
+      shell: bash
+      run: |
+        # Install ninja
+        source ./build/common/get-ninja.sh

.github/workflows/android-continuous.yml

@@ -16,6 +16,9 @@ jobs:
 
     steps:
       - uses: actions/checkout@v4.1.6
+        with:
+          fetch-depth: 0
+      - uses: ./.github/actions/linux-prereq
       - name: Run Android Continuous
         uses: ./.github/actions/android-continuous
         with:

.github/workflows/ios-continuous.yml

@@ -14,6 +14,9 @@ jobs:
 
     steps:
       - uses: actions/checkout@v4.1.6
+        with:
+          fetch-depth: 0
+      - uses: ./.github/actions/mac-prereq
       - name: Run build script
         run: |
           cd build/ios && printf "y" | ./build.sh continuous

.github/workflows/linux-continuous.yml

@@ -14,6 +14,9 @@ jobs:
 
     steps:
       - uses: actions/checkout@v4.1.6
+        with:
+          fetch-depth: 0
+      - uses: ./.github/actions/linux-prereq
       - name: Run build script
         run: |
           cd build/linux && printf "y" | ./build.sh continuous

.github/workflows/mac-continuous.yml

@@ -14,6 +14,9 @@ jobs:
 
     steps:
       - uses: actions/checkout@v4.1.6
+        with:
+          fetch-depth: 0
+      - uses: ./.github/actions/mac-prereq
       - name: Run build script
         run: |
           cd build/mac && printf "y" | ./build.sh continuous

.github/workflows/presubmit.yml

@@ -9,20 +9,32 @@ on:
     - main
 
 jobs:
-  build-desktop:
-    name: build-desktop
-    runs-on: ${{ matrix.os }}
-
-    strategy:
-      matrix:
-        os: [macos-14-xlarge, ubuntu-22.04-16core]
-
+  build-desktop-mac:
+    name: build-mac
+    runs-on: macos-14-xlarge
     steps:
       - uses: actions/checkout@v4.1.6
+        with:
+          fetch-depth: 0
+      - uses: ./.github/actions/mac-prereq
       - name: Run build script
         run: |
-          WORKFLOW_OS=`echo \`uname\` | sed "s/Darwin/mac/" | tr [:upper:] [:lower:]`
-          cd build/$WORKFLOW_OS && printf "y" | ./build.sh presubmit
+          cd build/mac && printf "y" | ./build.sh presubmit
+      - name: Test material parser
+        run: |
+          out/cmake-release/filament/test/test_material_parser
+
+  build-desktop-linux:
+    name: build-linux
+    runs-on: ubuntu-22.04-16core
+    steps:
+      - uses: actions/checkout@v4.1.6
+        with:
+          fetch-depth: 0
+      - uses: ./.github/actions/linux-prereq
+      - name: Run build script
+        run: |
+          cd build/linux && printf "y" | ./build.sh presubmit
       - name: Test material parser
         run: |
           out/cmake-release/filament/test/test_material_parser
@@ -33,6 +45,8 @@ jobs:
 
     steps:
       - uses: actions/checkout@v4.1.6
+        with:
+          fetch-depth: 0
       - name: Run build script
         run: |
           build\windows\build-github.bat presubmit
@@ -44,6 +58,9 @@ jobs:
 
     steps:
       - uses: actions/checkout@v4.1.6
+        with:
+          fetch-depth: 0
+      - uses: ./.github/actions/linux-prereq
       - uses: actions/setup-java@v3
         with:
           distribution: 'temurin'
@@ -60,6 +77,9 @@ jobs:
 
     steps:
       - uses: actions/checkout@v4.1.6
+        with:
+          fetch-depth: 0
+      - uses: ./.github/actions/mac-prereq
       - name: Run build script
         run: |
           cd build/ios && printf "y" | ./build.sh presubmit
@@ -73,6 +93,9 @@ jobs:
 
     steps:
       - uses: actions/checkout@v4.1.6
+        with:
+          fetch-depth: 0
+      - uses: ./.github/actions/linux-prereq
       - name: Run build script
         run: |
           cd build/web && printf "y" | ./build.sh presubmit
@@ -95,18 +118,20 @@ jobs:
     runs-on: macos-14-xlarge
     steps:
       - uses: actions/checkout@v4.1.6
-      - name: Set up Homebrew
-        id: set-up-homebrew
-        uses: Homebrew/actions/setup-homebrew@master
-      - name: Set up Python
-        uses: actions/setup-python@v5
         with:
-          python-version: '3.x'
-      - name: Install python prereqs
-        run: pip install mako setuptools pyyaml
-      - name: Run script
-        run: |
-          bash test/renderdiff/test.sh
+          fetch-depth: 0
+      - uses: ./.github/actions/mac-prereq
+      - name: Cache Mesa and deps
+        id: mesa-cache
+        uses: actions/cache@v4 # Use a specific version
+        with:
+          path: mesa
+          key: ${{ runner.os }}-mesa-deps-2-${{ vars.MESA_VERSION }}
+      - name: Get Mesa
+        id: mesa-prereq
+        run: bash test/utils/get_mesa.sh
+      - name: Run Test
+        run: bash test/renderdiff/test.sh
       - uses: actions/upload-artifact@v4
         with:
           name: presubmit-renderdiff-result
@@ -115,10 +140,33 @@ jobs:
   validate-wgsl-webgpu:
     name: validate-wgsl-webgpu
     runs-on: 'ubuntu-24.04-8core'
-
     steps:
       - uses: actions/checkout@v4.1.6
+        with:
+          fetch-depth: 0
+      - uses: ./.github/actions/linux-prereq
       - name: Run build script
-        run: source ./build/linux/ci-common.sh && ./build.sh -W debug test_filamat filament
+        run: ./build.sh -W debug test_filamat filament
       - name: Run test
         run: ./out/cmake-debug/libs/filamat/test_filamat --gtest_filter=MaterialCompiler.Wgsl*
+
+  code-correcteness:
+    name: code-correctness
+    runs-on: 'macos-14-xlarge'
+    steps:
+      - uses: actions/checkout@v4.1.6
+        with:
+          fetch-depth: 0
+      - uses: ./.github/actions/mac-prereq
+      - name: Install clang-tidy and deps
+        run: |
+          pip install pyyaml
+          brew install llvm@${GITHUB_LLVM_VERSION}
+          sudo ln -s "$(brew --prefix llvm)@${GITHUB_LLVM_VERSION}/bin/clang-tidy" "/usr/local/bin/clang-tidy"
+      - name: Run build script
+        # We need to build before clang-tidy can run analysis
+        run: |
+          # This will build for all three desktop backends on mac
+          ./build.sh -p desktop debug gltf_viewer
+      - name: Run test
+        run: bash test/code-correctness/test.sh

.github/workflows/release.yml

@@ -29,8 +29,42 @@ on:
     types: [created]
 
 jobs:
-  build-desktop:
-    name: build-desktop
+  build-linux:
+    name: build-linux
+    runs-on: ubuntu-22.04-32core
+    if: github.event_name == 'release' || github.event.inputs.platform == 'desktop'
+
+    steps:
+      - name: Decide Git ref
+        id: git_ref
+        run: |
+          REF=${RELEASE_TAG:-${GITHUB_REF}}
+          TAG=${REF##*/}
+          echo "ref=${REF}" >> $GITHUB_OUTPUT
+          echo "tag=${TAG}" >> $GITHUB_OUTPUT
+      - uses: actions/checkout@v4.1.6
+        with:
+          ref: ${{ steps.git_ref.outputs.ref }}
+      - uses: ./.github/actions/linux-prereq
+      - name: Run build script
+        env:
+          TAG: ${{ steps.git_ref.outputs.tag }}
+        run: |
+          cd build/linux && printf "y" | ./build.sh release
+          cd ../..
+          mv out/filament-release-linux.tgz out/filament-${TAG}-linux.tgz
+      - uses: actions/github-script@v6
+        env:
+          TAG: ${{ steps.git_ref.outputs.tag }}
+        with:
+          script: |
+            const upload = require('./build/common/upload-release-assets');
+            const { TAG } = process.env;
+            const globber = await glob.create('out/*.tgz');
+            await upload({ github, context }, await globber.glob(), TAG);
+
+  build-mac:
+    name: build-mac
     runs-on: ${{ matrix.os }}
     if: github.event_name == 'release' || github.event.inputs.platform == 'desktop'
 
@@ -49,15 +83,14 @@ jobs:
       - uses: actions/checkout@v4.1.6
         with:
           ref: ${{ steps.git_ref.outputs.ref }}
+      - uses: ./.github/actions/mac-prereq
       - name: Run build script
         env:
           TAG: ${{ steps.git_ref.outputs.tag }}
         run: |
-          WORKFLOW_OS=`echo \`uname\` | sed "s/Darwin/mac/" | tr [:upper:] [:lower:]`
-          cd build/$WORKFLOW_OS && printf "y" | ./build.sh release
+          cd build/mac && printf "y" | ./build.sh release
           cd ../..
-          if [ -f out/filament-release-darwin.tgz ]; then mv out/filament-release-darwin.tgz out/filament-${TAG}-mac.tgz; fi;
-          if [ -f out/filament-release-linux.tgz ]; then mv out/filament-release-linux.tgz out/filament-${TAG}-linux.tgz; fi;
+          mv out/filament-release-darwin.tgz out/filament-${TAG}-mac.tgz
       - uses: actions/github-script@v6
         env:
           TAG: ${{ steps.git_ref.outputs.tag }}
@@ -84,6 +117,7 @@ jobs:
       - uses: actions/checkout@v4.1.6
         with:
           ref: ${{ steps.git_ref.outputs.ref }}
+      - uses: ./.github/actions/linux-prereq
       - name: Run build script
         env:
           TAG: ${{ steps.git_ref.outputs.tag }}
@@ -121,6 +155,7 @@ jobs:
         with:
           distribution: 'temurin'
           java-version: '17'
+      - uses: ./.github/actions/linux-prereq
       - name: Run build script
         env:
           TAG: ${{ steps.git_ref.outputs.tag }}
@@ -171,6 +206,7 @@ jobs:
       - uses: actions/checkout@v4.1.6
         with:
           ref: ${{ steps.git_ref.outputs.ref }}
+      - uses: ./.github/actions/mac-prereq
       - name: Run build script
         env:
           TAG: ${{ steps.git_ref.outputs.tag }}

.github/workflows/web-continuous.yml

@@ -14,6 +14,9 @@ jobs:
 
     steps:
       - uses: actions/checkout@v4.1.6
+        with:
+          fetch-depth: 0
+      - uses: ./.github/actions/linux-prereq
       - name: Run build script
         run: |
           cd build/web && printf "y" | ./build.sh continuous

CMakeLists.txt

@@ -334,6 +334,9 @@ if (MSVC)
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${CXX_STANDARD} /W0 /Zc:__cplusplus")
 else()
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${CXX_STANDARD} -fstrict-aliasing -Wno-unknown-pragmas -Wno-unused-function -Wno-deprecated-declarations")
+    if (APPLE)
+        set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-nullability-extension")
+    endif()
 endif()
 
 if (FILAMENT_USE_EXTERNAL_GLES3)
@@ -798,6 +801,7 @@ add_subdirectory(${EXTERNAL}/draco/tnt)
 add_subdirectory(${EXTERNAL}/jsmn/tnt)
 add_subdirectory(${EXTERNAL}/stb/tnt)
 add_subdirectory(${EXTERNAL}/getopt)
+add_subdirectory(${EXTERNAL}/perfetto/tnt)
 
 # Note that this has to be placed after mikktspace in order for combine_static_libs to work.
 add_subdirectory(${LIBRARIES}/geometry)

README.md

@@ -31,7 +31,7 @@ repositories {
 }
 
 dependencies {
-    implementation 'com.google.android.filament:filament-android:1.59.0'
+    implementation 'com.google.android.filament:filament-android:1.59.4'
 }
 ```
 
@@ -51,7 +51,7 @@ Here are all the libraries available in the group `com.google.android.filament`:
 iOS projects can use CocoaPods to install the latest release:
 
 ```shell
-pod 'Filament', '~> 1.59.0'
+pod 'Filament', '~> 1.59.4'
 ```
 
 ## Documentation

RELEASE_NOTES.md

@@ -7,6 +7,22 @@ A new header is inserted each time a *tag* is created.
 Instead, if you are authoring a PR for the main branch, add your release note to
 [NEW_RELEASE_NOTES.md](./NEW_RELEASE_NOTES.md).
 
+## v1.59.5
+
+
+## v1.59.4
+
+
+## v1.59.3
+
+
+## v1.59.2
+
+- Fix build/compile errors when upgrading to MacOS 15.4
+
+## v1.59.1
+
+
 ## v1.59.0
 
 - materials: five custom variables (varyings) are now available on the condition that the `color` attribute is not requested (b/404930099). [⚠️ **New Material Version**]

android/buildSrc/src/main/groovy/FilamentPlugin.groovy

@@ -142,6 +142,12 @@ abstract class MaterialCompiler extends TaskWithBinary {
                 if (!exclude_vulkan) {
                     matcArgs += ['-a', 'vulkan']
                 }
+                def include_webgpu = providers
+                        .gradleProperty("com.google.android.filament.include-webgpu")
+                        .forUseAtConfigurationTime().present
+                if (include_webgpu) {
+                    matcArgs += ['-a', 'webgpu', '--variant-filter=skinning,stereo']
+                }
 
                 def mat_no_opt = providers
                         .gradleProperty("com.google.android.filament.matnopt")

android/filamat-android/CMakeLists.txt

@@ -26,6 +26,10 @@ add_library(utils STATIC IMPORTED)
 set_target_properties(utils PROPERTIES IMPORTED_LOCATION
         ${FILAMENT_DIR}/lib/${ANDROID_ABI}/libutils.a)
 
+add_library(perfetto STATIC IMPORTED)
+set_target_properties(perfetto PROPERTIES IMPORTED_LOCATION
+        ${FILAMENT_DIR}/lib/${ANDROID_ABI}/libperfetto.a)
+
 add_library(filabridge STATIC IMPORTED)
 set_target_properties(filabridge PROPERTIES IMPORTED_LOCATION
         ${FILAMENT_DIR}/lib/${ANDROID_ABI}/libfilabridge.a)
@@ -40,6 +44,7 @@ set_target_properties(shaders PROPERTIES IMPORTED_LOCATION
 
 set(FILAMAT_INCLUDE_DIRS
         ../../libs/utils/include
+        ../../third_party/perfetto
         )
 
 include_directories(${FILAMENT_DIR}/include)
@@ -55,6 +60,7 @@ target_link_libraries(filamat-jni
         filabridge
         shaders
         utils
+        perfetto
         log
         smol-v
         $<$<STREQUAL:${FILAMENT_SUPPORTS_WEBGPU},ON>:tint>

android/filament-android/CMakeLists.txt

@@ -21,6 +21,10 @@ add_library(utils STATIC IMPORTED)
 set_target_properties(utils PROPERTIES IMPORTED_LOCATION
         ${FILAMENT_DIR}/lib/${ANDROID_ABI}/libutils.a)
 
+add_library(perfetto STATIC IMPORTED)
+set_target_properties(perfetto PROPERTIES IMPORTED_LOCATION
+        ${FILAMENT_DIR}/lib/${ANDROID_ABI}/libperfetto.a)
+
 add_library(ibl-lite STATIC IMPORTED)
 set_target_properties(ibl-lite PROPERTIES IMPORTED_LOCATION
         ${FILAMENT_DIR}/lib/${ANDROID_ABI}/libibl-lite.a)
@@ -123,6 +127,7 @@ target_link_libraries(filament-jni
     PRIVATE android
     PRIVATE jnigraphics
     PRIVATE utils
+    PRIVATE perfetto
 
     # libgeometry is PUBLIC because gltfio uses it.
     PUBLIC geometry
@@ -141,6 +146,7 @@ target_include_directories(filament-jni PRIVATE
         ${FILAMENT_DIR}/include
         ../../filament/backend/include
         ../../third_party/robin-map
+        ../../third_party/perfetto
         ../../libs/utils/include)
 
 # Force a relink when the version script is changed:

android/filament-android/src/main/java/com/google/android/filament/View.java

@@ -1980,7 +1980,7 @@ public class View {
         }
 
         /**
-         * reconstruction filter width typically between 0.2 (sharper, aliased) and 1.5 (smoother)
+         * reconstruction filter width typically between 1 (sharper) and 2 (smoother)
          */
         public float filterWidth = 1.0f;
         /**

android/gltfio-android/CMakeLists.txt

@@ -35,6 +35,10 @@ add_library(utils STATIC IMPORTED)
 set_target_properties(utils PROPERTIES IMPORTED_LOCATION
         ${FILAMENT_DIR}/lib/${ANDROID_ABI}/libutils.a)
 
+add_library(perfetto STATIC IMPORTED)
+set_target_properties(perfetto PROPERTIES IMPORTED_LOCATION
+        ${FILAMENT_DIR}/lib/${ANDROID_ABI}/libperfetto.a)
+
 add_library(uberzlib STATIC IMPORTED)
 set_target_properties(uberzlib PROPERTIES IMPORTED_LOCATION
         ${FILAMENT_DIR}/lib/${ANDROID_ABI}/libuberzlib.a)
@@ -121,6 +125,7 @@ set(GLTFIO_INCLUDE_DIRS
         ../../third_party/meshoptimizer/src
         ../../third_party/robin-map
         ../../third_party/stb
+        ../../third_party/perfetto
         ../../libs/utils/include
         ../../libs/ktxreader/include
 )
@@ -129,7 +134,7 @@ add_library(gltfio-jni SHARED ${GLTFIO_SRCS})
 target_include_directories(gltfio-jni PRIVATE ${GLTFIO_INCLUDE_DIRS})
 set_target_properties(gltfio-jni PROPERTIES LINK_DEPENDS ${CMAKE_CURRENT_SOURCE_DIR}/libgltfio-jni.symbols)
 set_target_properties(gltfio-jni PROPERTIES LINK_DEPENDS ${CMAKE_CURRENT_SOURCE_DIR}/libgltfio-jni.map)
-target_link_libraries(gltfio-jni filament-jni utils uberzlib log stb ktxreader basis_transcoder zstd uberarchive)
+target_link_libraries(gltfio-jni filament-jni utils perfetto uberzlib log stb ktxreader basis_transcoder zstd uberarchive)
 target_link_libraries(gltfio-jni dracodec meshoptimizer)
 target_compile_definitions(gltfio-jni PUBLIC GLTFIO_DRACO_SUPPORTED=1)
 target_include_directories(gltfio-jni PRIVATE ${DRACO_DIR}/src)

android/gradle.properties

@@ -1,5 +1,5 @@
 GROUP=com.google.android.filament
-VERSION_NAME=1.59.0
+VERSION_NAME=1.59.4
 
 POM_DESCRIPTION=Real-time physically based rendering engine for Android.
 

build/android/build.sh

@@ -14,12 +14,12 @@ echo "Please refer to BUILDING.md for more information."
 read -r -p "Do you wish to proceed (y/n)? " choice
 case "${choice}" in
     y|Y)
-	      echo "Build will proceed..."
-	      ;;
+              echo "Build will proceed..."
+              ;;
     n|N)
-    	  exit 0
-    	  ;;
-	  *)
+          exit 0
+          ;;
+          *)
         exit 0
         ;;
 esac
@@ -30,30 +30,27 @@ set -x
 UNAME=`echo $(uname)`
 LC_UNAME=`echo $UNAME | tr '[:upper:]' '[:lower:]'`
 
-FILAMENT_ANDROID_CI_BUILD=true
-
 # build-common.sh will generate the following variables:
 #     $GENERATE_ARCHIVES
 #     $BUILD_DEBUG
 #     $BUILD_RELEASE
 source `dirname $0`/../common/ci-common.sh
-if [[  "$LC_UNAME" == "linux" ]]; then
-    source `dirname $0`/../linux/ci-common.sh
-elif [[ "$LC_UNAME" == "darwin" ]]; then
-    source `dirname $0`/../mac/ci-common.sh
-fi
 source `dirname $0`/../common/build-common.sh
 
 if [[ "$GITHUB_WORKFLOW" ]]; then
     java_version=$(java -version 2>&1 | head -1 | cut -d'"' -f2 | sed '/^1\./s///' | cut -d'.' -f1)
     if [[ "$java_version" < 17 ]]; then
         echo "Android builds require Java 17, found version ${java_version} instead"
-        exit 0
+        exit 1
     fi
 fi
 
 # Unless explicitly specified, NDK version will be set to match exactly the required one
-FILAMENT_NDK_VERSION=${FILAMENT_NDK_VERSION:-$(cat `dirname $0`/ndk.version)}
+FILAMENT_NDK_VERSION=${GITHUB_NDK_VERSION:-27.0.11718014}
+
+(! grep "${FILAMENT_NDK_VERSION}" `dirname $0`/../../android/build.gradle > /dev/null) &&
+    echo "Mismatch of NDK versions: want ${FILAMENT_NDK_VERSION} and not found in android/build.gradle" &&
+    exit 1
 
 # Install the required NDK version specifically (if not present)
 if [[ ! -d "${ANDROID_HOME}/ndk/$FILAMENT_NDK_VERSION" ]]; then

build/android/ndk.version

@@ -1 +0,0 @@
-27.0.11718014

build/common/check-headers.sh

@@ -56,10 +56,16 @@ popd >/dev/null
 rm -rf out/check-headers
 mkdir -p out/check-headers
 
+TMP_FILE=out/check-headers/temp.cpp
 echo "Checking that public headers compile independently..."
 for include in "${includes[@]}"; do
+    rm -f ${TMP_FILE}
     echo "Checking ${include}"
-    echo "#include <${include}>" >> out/check-headers/temp.cpp
-    clang -std=c++17 -I "${FILAMENT_HEADERS}" out/check-headers/temp.cpp -c -o /dev/null
+    if [[ "${include}" == "utils/Systrace.h" ]]; then
+        # A necessary define before we can include utils/Systrace.h
+        echo "#define SYSTRACE_TAG SYSTRACE_TAG_DISABLED" >> ${TMP_FILE}
+    fi
+    echo "#include <${include}>" >> ${TMP_FILE}
+    clang -std=c++17 -I "${FILAMENT_HEADERS}" ${TMP_FILE} -c -o /dev/null
 done
 echo "Done!"

build/common/ci-common.sh

@@ -2,5 +2,4 @@
 
 if [[ "$GITHUB_WORKFLOW" ]]; then
     echo "Running workflow $GITHUB_WORKFLOW (event: $GITHUB_EVENT_NAME, action: $GITHUB_ACTION)"
-    CONTINUOUS_INTEGRATION=true
 fi

build/common/get-ninja.sh

@@ -0,0 +1,18 @@
+#!/bin/bash
+
+if [[ "$GITHUB_WORKFLOW" ]]; then
+    OS_NAME=$(uname -s)
+    NINJA_DL_DIR=/tmp/ninja-dl
+    NINJA_PLATFORM=
+    if [[ "$OS_NAME" == "Linux" ]]; then
+        NINJA_PLATFORM=linux
+    elif [[ "$OS_NAME" == "Darwin" ]]; then
+        NINJA_PLATFORM=mac
+    fi
+    curl -L -o /tmp/ninja-dl.zip https://github.com/ninja-build/ninja/releases/download/v${GITHUB_NINJA_VERSION}/ninja-${NINJA_PLATFORM}.zip
+    mkdir -p $NINJA_DL_DIR
+    unzip -q /tmp/ninja-dl.zip -d $NINJA_DL_DIR
+    chmod +x ${NINJA_DL_DIR}/ninja
+    # Install ninja globally for AGP
+    sudo cp ${NINJA_DL_DIR}/ninja /usr/local/bin/
+fi

build/common/versions

@@ -0,0 +1,6 @@
+GITHUB_CLANG_VERSION=14
+GITHUB_CMAKE_VERSION=3.19.5
+GITHUB_NINJA_VERSION=1.10.2
+GITHUB_MESA_VERSION=24.2.1
+GITHUB_LLVM_VERSION=16
+GITHUB_NDK_VERSION=27.0.11718014

build/ios/build.sh

@@ -28,7 +28,6 @@ set -e
 set -x
 
 source `dirname $0`/../common/ci-common.sh
-source `dirname $0`/ci-common.sh
 source `dirname $0`/../common/build-common.sh
 
 pushd `dirname $0`/../.. > /dev/null
@@ -41,4 +40,3 @@ if [[ "${GENERATE_ARCHIVES}" ]]; then
 fi
 
 ./build.sh -i -p ios -c $BUILD_SIMULATOR $GENERATE_ARCHIVES $BUILD_DEBUG $BUILD_RELEASE
-

build/ios/ci-common.sh

@@ -1,6 +0,0 @@
-#!/bin/bash
-
-curl -OL https://github.com/ninja-build/ninja/releases/download/v1.10.2/ninja-mac.zip
-unzip -q ninja-mac.zip
-chmod +x ninja
-export PATH="$PWD:$PATH"

build/linux/build.sh

@@ -32,7 +32,6 @@ set -x
 #     $BUILD_DEBUG
 #     $BUILD_RELEASE
 source `dirname $0`/../common/ci-common.sh
-source `dirname $0`/ci-common.sh
 source `dirname $0`/../common/build-common.sh
 
 pushd `dirname $0`/../.. > /dev/null

build/linux/ci-common.sh

@@ -1,38 +0,0 @@
-#!/bin/bash
-
-# version of clang we want to use
-export GITHUB_CLANG_VERSION=14
-# version of CMake to use instead of the default one
-export GITHUB_CMAKE_VERSION=3.19.5
-# version of ninja to use
-export GITHUB_NINJA_VERSION=1.10.2
-
-# Steps for GitHub Workflows
-if [[ "$GITHUB_WORKFLOW" ]]; then
-    # Install ninja
-    wget -q https://github.com/ninja-build/ninja/releases/download/v$GITHUB_NINJA_VERSION/ninja-linux.zip
-    unzip -q ninja-linux.zip
-    export PATH="$PWD:$PATH"
-
-    # Install CMake
-    mkdir -p cmake
-    cd cmake
-
-    sudo wget https://github.com/Kitware/CMake/releases/download/v$GITHUB_CMAKE_VERSION/cmake-$GITHUB_CMAKE_VERSION-Linux-x86_64.sh
-    sudo chmod +x ./cmake-$GITHUB_CMAKE_VERSION-Linux-x86_64.sh
-    sudo ./cmake-$GITHUB_CMAKE_VERSION-Linux-x86_64.sh --skip-license > /dev/null
-    sudo update-alternatives --install /usr/bin/cmake cmake $(pwd)/bin/cmake 1000 --force
-
-    cd ..
-
-    sudo wget -O - https://apt.llvm.org/llvm-snapshot.gpg.key | sudo apt-key add -
-    sudo apt-get update
-    sudo apt-get install clang-$GITHUB_CLANG_VERSION libc++-$GITHUB_CLANG_VERSION-dev libc++abi-$GITHUB_CLANG_VERSION-dev
-    sudo apt-get install mesa-common-dev libxi-dev libxxf86vm-dev
-
-    # For dawn
-    sudo apt-get install libxrandr-dev libxinerama-dev libxcursor-dev libxi-dev libx11-xcb-dev
-
-    sudo update-alternatives --install /usr/bin/cc cc /usr/bin/clang-${GITHUB_CLANG_VERSION} 100
-    sudo update-alternatives --install /usr/bin/c++ c++ /usr/bin/clang++-${GITHUB_CLANG_VERSION} 100
-fi

build/mac/build.sh

@@ -28,7 +28,6 @@ set -e
 set -x
 
 source `dirname $0`/../common/ci-common.sh
-source `dirname $0`/ci-common.sh
 source `dirname $0`/../common/build-common.sh
 
 pushd `dirname $0`/../.. > /dev/null

build/mac/ci-common.sh

@@ -1,8 +0,0 @@
-#!/bin/bash
-
-curl -OL https://github.com/ninja-build/ninja/releases/download/v1.10.2/ninja-mac.zip
-unzip -q ninja-mac.zip
-chmod +x ninja
-# Install ninja globally for AGP
-cp ninja /usr/local/bin
-export PATH="$PWD:$PATH"

build/toolchain-aarch64-linux-android.cmake

@@ -31,10 +31,16 @@ set(DIST_ARCH arm64-v8a)
 string(TOLOWER ${CMAKE_HOST_SYSTEM_NAME} HOST_NAME_L)
 file(TO_CMAKE_PATH $ENV{ANDROID_HOME} ANDROID_HOME_UNIX)
 
+message(STATUS "Try using NDK \'${FILAMENT_NDK_VERSION}\'")
 if (NOT FILAMENT_NDK_VERSION)
-    file(READ "${CMAKE_CURRENT_LIST_DIR}/android/ndk.version" FILAMENT_NDK_VERSION)
-    string(REGEX MATCH "^\\d+" FILAMENT_NDK_VERSION ${FILAMENT_NDK_VERSION})
+    file(READ "${CMAKE_CURRENT_LIST_DIR}/common/versions" VERSIONS_STR)
+    string(REGEX MATCH "GITHUB_NDK_VERSION=(\\d+)" _UNUSED ${VERSIONS_STR})
+    if(CMAKE_MATCH_1)
+        set(FILAMENT_NDK_VERSION "${CMAKE_MATCH_1}")
+    endif()
 endif()
+message(STATUS "Using NDK \'${FILAMENT_NDK_VERSION}\'")
+
 file(GLOB NDK_VERSIONS LIST_DIRECTORIES true ${ANDROID_HOME_UNIX}/ndk/${FILAMENT_NDK_VERSION}*)
 list(SORT NDK_VERSIONS)
 list(GET NDK_VERSIONS -1 NDK_VERSION)

build/toolchain-arm7-linux-android.cmake

@@ -32,10 +32,16 @@ set(DIST_ARCH armeabi-v7a)
 string(TOLOWER ${CMAKE_HOST_SYSTEM_NAME} HOST_NAME_L)
 file(TO_CMAKE_PATH $ENV{ANDROID_HOME} ANDROID_HOME_UNIX)
 
+message(STATUS "Try using NDK \'${FILAMENT_NDK_VERSION}\'")
 if (NOT FILAMENT_NDK_VERSION)
-    file(READ "${CMAKE_CURRENT_LIST_DIR}/android/ndk.version" FILAMENT_NDK_VERSION)
-    string(REGEX MATCH "^\\d+" FILAMENT_NDK_VERSION ${FILAMENT_NDK_VERSION})
+    file(READ "${CMAKE_CURRENT_LIST_DIR}/common/versions" VERSIONS_STR)
+    string(REGEX MATCH "GITHUB_NDK_VERSION=(\\d+)" _UNUSED ${VERSIONS_STR})
+    if(CMAKE_MATCH_1)
+        set(FILAMENT_NDK_VERSION "${CMAKE_MATCH_1}")
+    endif()
 endif()
+message(STATUS "Using NDK \'${FILAMENT_NDK_VERSION}\'")
+
 file(GLOB NDK_VERSIONS LIST_DIRECTORIES true ${ANDROID_HOME_UNIX}/ndk/${FILAMENT_NDK_VERSION}*)
 list(SORT NDK_VERSIONS)
 list(GET NDK_VERSIONS -1 NDK_VERSION)

build/toolchain-x86-linux-android.cmake

@@ -31,10 +31,16 @@ set(DIST_ARCH x86)
 string(TOLOWER ${CMAKE_HOST_SYSTEM_NAME} HOST_NAME_L)
 file(TO_CMAKE_PATH $ENV{ANDROID_HOME} ANDROID_HOME_UNIX)
 
+message(STATUS "Try using NDK \'${FILAMENT_NDK_VERSION}\'")
 if (NOT FILAMENT_NDK_VERSION)
-    file(READ "${CMAKE_CURRENT_LIST_DIR}/android/ndk.version" FILAMENT_NDK_VERSION)
-    string(REGEX MATCH "^\\d+" FILAMENT_NDK_VERSION ${FILAMENT_NDK_VERSION})
+    file(READ "${CMAKE_CURRENT_LIST_DIR}/common/versions" VERSIONS_STR)
+    string(REGEX MATCH "GITHUB_NDK_VERSION=(\\d+)" _UNUSED ${VERSIONS_STR})
+    if(CMAKE_MATCH_1)
+        set(FILAMENT_NDK_VERSION "${CMAKE_MATCH_1}")
+    endif()
 endif()
+message(STATUS "Using NDK \'${FILAMENT_NDK_VERSION}\'")
+
 file(GLOB NDK_VERSIONS LIST_DIRECTORIES true ${ANDROID_HOME_UNIX}/ndk/${FILAMENT_NDK_VERSION}*)
 list(SORT NDK_VERSIONS)
 list(GET NDK_VERSIONS -1 NDK_VERSION)

build/toolchain-x86_64-linux-android.cmake

@@ -31,10 +31,16 @@ set(DIST_ARCH x86_64)
 string(TOLOWER ${CMAKE_HOST_SYSTEM_NAME} HOST_NAME_L)
 file(TO_CMAKE_PATH $ENV{ANDROID_HOME} ANDROID_HOME_UNIX)
 
+message(STATUS "Try using NDK \'${FILAMENT_NDK_VERSION}\'")
 if (NOT FILAMENT_NDK_VERSION)
-    file(READ "${CMAKE_CURRENT_LIST_DIR}/android/ndk.version" FILAMENT_NDK_VERSION)
-    string(REGEX MATCH "^\\d+" FILAMENT_NDK_VERSION ${FILAMENT_NDK_VERSION})
+    file(READ "${CMAKE_CURRENT_LIST_DIR}/common/versions" VERSIONS_STR)
+    string(REGEX MATCH "GITHUB_NDK_VERSION=(\\d+)" _UNUSED ${VERSIONS_STR})
+    if(CMAKE_MATCH_1)
+        set(FILAMENT_NDK_VERSION "${CMAKE_MATCH_1}")
+    endif()
 endif()
+message(STATUS "Using NDK \'${FILAMENT_NDK_VERSION}\'")
+
 file(GLOB NDK_VERSIONS LIST_DIRECTORIES true ${ANDROID_HOME_UNIX}/ndk/${FILAMENT_NDK_VERSION}*)
 list(SORT NDK_VERSIONS)
 list(GET NDK_VERSIONS -1 NDK_VERSION)

build/web/ci-common.sh

@@ -1,16 +1,4 @@
 #!/bin/bash
-if [ `uname` == "Linux" ];then
-    source `dirname $0`/../linux/ci-common.sh
-elif [ `uname` == "Darwin" ];then
-    curl -OL https://github.com/ninja-build/ninja/releases/download/v1.10.2/ninja-mac.zip
-    unzip -q ninja-mac.zip
-else
-    echo "Unsupported OS"
-    exit 1
-fi
-
-chmod +x ninja
-export PATH="$PWD:$PATH"
 
 # Install emscripten.
 curl -L https://github.com/emscripten-core/emsdk/archive/refs/tags/3.1.60.zip > emsdk.zip

docs/Materials.html

@@ -166,7 +166,7 @@ This document is part of the <a href="https://github.com/google/filament">Filame
 </p><ul>
 <li class="minus"><a href="https://github.com/romainguy">Romain Guy</a>, <a href="https://twitter.com/romainguy">@romainguy</a>
 </li>
-<li class="minus"><a href="https://github.com/pixelflinger">Mathias Agopian</a>, <a href="https://twitter.com/darthmoosious">@darthmoosious</a></li></ul>
+<li class="minus"><a href="https://github.com/pixelflinger">Mathias Agopian</a>, <a href="https://bsky.app/profile/pixelflinger.bsky.social">@pixelflinger</a></li></ul>
 
 <p></p>
 <a class="target" name="overview">&nbsp;</a><a class="target" name="overview">&nbsp;</a><a class="target" name="toc2">&nbsp;</a><h1>Overview</h1>
@@ -259,26 +259,27 @@ in <a href="#table_standardproperties">table&nbsp;1</a>.
 </p><div class="table">
 <table class="table"><tbody><tr><th style="text-align:right"> Property </th><th style="text-align:left"> Definition </th></tr>
 <tr><td style="text-align:right"> <strong class="asterisk">baseColor</strong> </td><td style="text-align:left"> Diffuse albedo for non-metallic surfaces, and specular color for metallic surfaces </td></tr>
-<tr><td style="text-align:right"> <strong class="asterisk">metallic</strong> </td><td style="text-align:left"> Whether a surface appears to be dielectric (0.0) or conductor (1.0). Often used as a binary value (0 or 1) </td></tr>
 <tr><td style="text-align:right"> <strong class="asterisk">roughness</strong> </td><td style="text-align:left"> Perceived smoothness (1.0) or roughness (0.0) of a surface. Smooth surfaces exhibit sharp reflections </td></tr>
+<tr><td style="text-align:right"> <strong class="asterisk">metallic</strong> </td><td style="text-align:left"> Whether a surface appears to be dielectric (0.0) or conductor (1.0). Often used as a binary value (0 or 1) </td></tr>
 <tr><td style="text-align:right"> <strong class="asterisk">reflectance</strong> </td><td style="text-align:left"> Fresnel reflectance at normal incidence for dielectric surfaces. This directly controls the strength of the reflections </td></tr>
-<tr><td style="text-align:right"> <strong class="asterisk">sheenColor</strong> </td><td style="text-align:left"> Strength of the sheen layer </td></tr>
-<tr><td style="text-align:right"> <strong class="asterisk">sheenRoughness</strong> </td><td style="text-align:left"> Perceived smoothness or roughness of the sheen layer </td></tr>
+<tr><td style="text-align:right"> <strong class="asterisk">ambientOcclusion</strong> </td><td style="text-align:left"> Defines how much of the ambient light is accessible to a surface point. It is a per-pixel shadowing factor between 0.0 and 1.0 </td></tr>
 <tr><td style="text-align:right"> <strong class="asterisk">clearCoat</strong> </td><td style="text-align:left"> Strength of the clear coat layer </td></tr>
 <tr><td style="text-align:right"> <strong class="asterisk">clearCoatRoughness</strong> </td><td style="text-align:left"> Perceived smoothness or roughness of the clear coat layer </td></tr>
+<tr><td style="text-align:right"> <strong class="asterisk">clearCoatNormal</strong> </td><td style="text-align:left"> A detail normal used to perturb the clear coat layer using <em class="underscore">bump mapping</em> (<em class="underscore">normal mapping</em>) </td></tr>
 <tr><td style="text-align:right"> <strong class="asterisk">anisotropy</strong> </td><td style="text-align:left"> Amount of anisotropy in either the tangent or bitangent direction </td></tr>
 <tr><td style="text-align:right"> <strong class="asterisk">anisotropyDirection</strong> </td><td style="text-align:left"> Local surface direction in tangent space </td></tr>
-<tr><td style="text-align:right"> <strong class="asterisk">ambientOcclusion</strong> </td><td style="text-align:left"> Defines how much of the ambient light is accessible to a surface point. It is a per-pixel shadowing factor between 0.0 and 1.0 </td></tr>
-<tr><td style="text-align:right"> <strong class="asterisk">normal</strong> </td><td style="text-align:left"> A detail normal used to perturb the surface using <em class="underscore">bump mapping</em> (<em class="underscore">normal mapping</em>) </td></tr>
-<tr><td style="text-align:right"> <strong class="asterisk">bentNormal</strong> </td><td style="text-align:left"> A normal pointing in the average unoccluded direction. Can be used to improve indirect lighting quality </td></tr>
-<tr><td style="text-align:right"> <strong class="asterisk">clearCoatNormal</strong> </td><td style="text-align:left"> A detail normal used to perturb the clear coat layer using <em class="underscore">bump mapping</em> (<em class="underscore">normal mapping</em>) </td></tr>
-<tr><td style="text-align:right"> <strong class="asterisk">emissive</strong> </td><td style="text-align:left"> Additional diffuse albedo to simulate emissive surfaces (such as neons, etc.) This property is mostly useful in an HDR pipeline with a bloom pass </td></tr>
-<tr><td style="text-align:right"> <strong class="asterisk">postLightingColor</strong> </td><td style="text-align:left"> Additional color that can be blended with the result of the lighting computations. See <code>postLightingBlending</code> </td></tr>
-<tr><td style="text-align:right"> <strong class="asterisk">ior</strong> </td><td style="text-align:left"> Index of refraction, either for refractive objects or as an alternative to reflectance </td></tr>
-<tr><td style="text-align:right"> <strong class="asterisk">transmission</strong> </td><td style="text-align:left"> Defines how much of the diffuse light of a dielectric is transmitted through the object, in other words this defines how transparent an object is </td></tr>
-<tr><td style="text-align:right"> <strong class="asterisk">absorption</strong> </td><td style="text-align:left"> Absorption factor for refractive objects </td></tr>
-<tr><td style="text-align:right"> <strong class="asterisk">microThickness</strong> </td><td style="text-align:left"> Thickness of the thin layer of refractive objects </td></tr>
 <tr><td style="text-align:right"> <strong class="asterisk">thickness</strong> </td><td style="text-align:left"> Thickness of the solid volume of refractive objects </td></tr>
+<tr><td style="text-align:right"> <strong class="asterisk">sheenColor</strong> </td><td style="text-align:left"> Strength of the sheen layer </td></tr>
+<tr><td style="text-align:right"> <strong class="asterisk">sheenRoughness</strong> </td><td style="text-align:left"> Perceived smoothness or roughness of the sheen layer </td></tr>
+<tr><td style="text-align:right"> <strong class="asterisk">emissive</strong> </td><td style="text-align:left"> Additional diffuse albedo to simulate emissive surfaces (such as neons, etc.) This property is mostly useful in an HDR pipeline with a bloom pass </td></tr>
+<tr><td style="text-align:right"> <strong class="asterisk">normal</strong> </td><td style="text-align:left"> A detail normal used to perturb the surface using <em class="underscore">bump mapping</em> (<em class="underscore">normal mapping</em>) </td></tr>
+<tr><td style="text-align:right"> <strong class="asterisk">postLightingColor</strong> </td><td style="text-align:left"> Additional color that can be blended with the result of the lighting computations. See <code>postLightingBlending</code> </td></tr>
+<tr><td style="text-align:right"> <strong class="asterisk">absorption</strong> </td><td style="text-align:left"> Absorption factor for refractive objects </td></tr>
+<tr><td style="text-align:right"> <strong class="asterisk">transmission</strong> </td><td style="text-align:left"> Defines how much of the diffuse light of a dielectric is transmitted through the object, in other words this defines how transparent an object is </td></tr>
+<tr><td style="text-align:right"> <strong class="asterisk">ior</strong> </td><td style="text-align:left"> Index of refraction, either for refractive objects or as an alternative to reflectance </td></tr>
+<tr><td style="text-align:right"> <strong class="asterisk">microThickness</strong> </td><td style="text-align:left"> Thickness of the thin layer of refractive objects </td></tr>
+<tr><td style="text-align:right"> <strong class="asterisk">bentNormal</strong> </td><td style="text-align:left"> A normal pointing in the average unoccluded direction. Can be used to improve indirect lighting quality </td></tr>
+<tr><td style="text-align:right"> <strong class="asterisk">shadowStrength</strong> </td><td style="text-align:left"> Strength factor between 0 and 1 for all shadows received by this material </td></tr>
 </tbody></table><center><div class="tablecaption"><a class="target" name="table_standardproperties">&nbsp;</a><b style="font-style:normal;">Table&nbsp;1:</b> Properties of the standard model</div></center></div>
 
 <p></p><p>
@@ -1486,10 +1487,13 @@ non-shader data.
 </p><dl><dt>Type</dt><dd><p>     array of parameter objects
 
 </p></dd><dt>Value</dt><dd><p>      Each entry is an object with the properties <code>name</code> and <code>type</code>, both of <code>string</code> type. The
-      name must be a valid GLSL identifier. Entries also have an optional <code>precision</code>, which can be
+      name must be a valid GLSL identifier. Entries have an optional <code>precision</code>, which can be
       one of <code>default</code> (best precision for the platform, typically <code>high</code> on desktop, <code>medium</code> on
       mobile), <code>low</code>, <code>medium</code>, <code>high</code>. The type must be one of the types described in
-      <a href="#table_materialparamstypes">table&nbsp;14</a>.
+      <a href="#table_materialparamstypes">table&nbsp;14</a>. For Android external textures, entries also have an optional 
+      transformName parameter to specify the name of the material parameter that will be 
+      used to expose the transform matrix associated with the external sampler. In iOS and Vulkan,
+      this will always be identity. 
 
 </p></dd></dl><div class="table">
 <table class="table"><tbody><tr><th style="text-align:left"> Type </th><th style="text-align:left"> Description </th></tr>
@@ -1752,7 +1756,13 @@ non-shader data.
       when selecting any shading model that is not <code>unlit</code>. See the shader sections of this document
       for more information on how to access these attributes from the shaders.
 
-</p></dd></dl><p></p><pre class="listing tilde"><code><span class="line">material {</span>
+</p></dd></dl><div class="admonition note"><div class="admonition-title"> Interaction with custom variables</div>
+
+<p></p><p>
+
+    When the <code>color</code> attribute is specified, only four custom variables are available instead of five.</p></div>
+
+<p></p><pre class="listing tilde"><code><span class="line">material {</span>
 <span class="line">    parameters : [</span>
 <span class="line">        {</span>
 <span class="line">           type : sampler2d,</span>
@@ -1779,7 +1789,7 @@ non-shader data.
 
 </p><dl><dt>Type</dt><dd><p>     array of <code>string</code>
 
-</p></dd><dt>Value</dt><dd><p>      Up to 4 strings, each must be a valid GLSL identifier.
+</p></dd><dt>Value</dt><dd><p>      Up to 5 strings, each must be a valid GLSL identifier.
 
 </p></dd><dt>Description</dt><dd><p>      Defines custom interpolants (or variables) that are output by the material's vertex shader.
       Each entry of the array defines the name of an  interpolant. The full name in the fragment
@@ -1794,7 +1804,14 @@ non-shader data.
       particular if <code>default</code> is specified the default precision is used is the fragment shader
       (<code>mediump</code>) and in the vertex shader (<code>highp</code>).
 
-</p></dd></dl><p></p><pre class="listing tilde"><code><span class="line">material {</span>
+</p></dd></dl><div class="admonition warning"><div class="admonition-title"> Interaction with required attributes</div>
+
+<p></p><p>
+
+    If the <code>color</code> attribute is specified in the <code>required</code> list, then only four variables can be used
+    instead of five.</p></div>
+
+<p></p><pre class="listing tilde"><code><span class="line">material {</span>
 <span class="line">    name : Skybox,</span>
 <span class="line">    parameters : [</span>
 <span class="line">        {</span>

docs/webgl/reference.html

@@ -49,7 +49,7 @@
 </tr>
 <tr>
 <td align="left"><a href="#EntityManager">EntityManager</a></td>
-<td align="left">Singleton used for constructing entities in Filament&#x27;s ECS.</td>
+<td align="left">Singleton used for constructing entities in Filament's ECS.</td>
 </tr>
 <tr>
 <td align="left"><a href="#Frustum">Frustum</a></td>
@@ -89,7 +89,7 @@
 </tr>
 <tr>
 <td align="left"><a href="#Renderer">Renderer</a></td>
-<td align="left">Represents the platform&#x27;s native window.</td>
+<td align="left">Represents the platform's native window.</td>
 </tr>
 <tr>
 <td align="left"><a href="#Scene">Scene</a></td>
@@ -97,7 +97,7 @@
 </tr>
 <tr>
 <td align="left"><a href="#SwapChain">SwapChain</a></td>
-<td align="left">Represents the platform&#x27;s native rendering surface.</td>
+<td align="left">Represents the platform's native rendering surface.</td>
 </tr>
 <tr>
 <td align="left"><a href="#Texture">Texture</a></td>
@@ -604,11 +604,11 @@
 </ul>
 <p>To create an entity with no components, use <a href="#EntityManager">EntityManager</a>.
 TODO: It would be better to expose these as JS numbers rather than as JS objects.
-This would also be more consistent with Filament&#x27;s Java bindings.</p>
+This would also be more consistent with Filament's Java bindings.</p>
 </div>
 <div class='classdoc'>
 <h2>class <a id='EntityManager' href='#EntityManager'>EntityManager</a></h2>
-<p>Singleton used for constructing entities in Filament&#x27;s ECS.</p>
+<p>Singleton used for constructing entities in Filament's ECS.</p>
 <ul>
 <li><strong>entityManager.create()</strong>
 <ul>
@@ -742,7 +742,7 @@ properties.</p>
 </ul>
 </li>
 </ul>
-<p>Be sure to call the instance&#x27;s <code>delete</code> method when you&#x27;re done with it.</p>
+<p>Be sure to call the instance's <code>delete</code> method when you're done with it.</p>
 </div>
 <div class='classdoc'>
 <h2>class <a id='PixelBufferDescriptor' href='#PixelBufferDescriptor'>PixelBufferDescriptor</a></h2>
@@ -780,11 +780,11 @@ properties.</p>
 </ul>
 </li>
 </ul>
-<p>Be sure to call the instance&#x27;s <code>delete</code> method when you&#x27;re done with it.</p>
+<p>Be sure to call the instance's <code>delete</code> method when you're done with it.</p>
 </div>
 <div class='classdoc'>
 <h2>class <a id='Renderer' href='#Renderer'>Renderer</a></h2>
-<p>Represents the platform&#x27;s native window.</p>
+<p>Represents the platform's native window.</p>
 <ul>
 <li><strong>renderer.render(swapChain, view)</strong>
 <ul>
@@ -803,7 +803,7 @@ properties.</p>
 </div>
 <div class='classdoc'>
 <h2>class <a id='SwapChain' href='#SwapChain'>SwapChain</a></h2>
-<p>Represents the platform&#x27;s native rendering surface.</p>
+<p>Represents the platform's native rendering surface.</p>
 <p>See also the <a href="#Engine">Engine</a> methods <code>createSwapChain</code> and <code>destroySwapChain</code>.</p>
 </div>
 <div class='classdoc'>
@@ -847,7 +847,7 @@ properties.</p>
 </ul>
 </li>
 </ul>
-<p>Be sure to call the instance&#x27;s <code>delete</code> method when you&#x27;re done with it.</p>
+<p>Be sure to call the instance's <code>delete</code> method when you're done with it.</p>
 </div>
 <div class='classdoc'>
 <h2>class <a id='VertexBuffer' href='#VertexBuffer'>VertexBuffer</a></h2>
@@ -944,7 +944,7 @@ See also the <a href="#Engine">Engine</a> methods <code>createView</code> and <c
 <ul>
 <li><strong>assets</strong>
 <ul>
-<li>Array of strings containing URL&#x27;s of required assets.</li>
+<li>Array of strings containing URL's of required assets.</li>
 </ul>
 </li>
 <li><strong>onDone</strong>
@@ -954,7 +954,7 @@ See also the <a href="#Engine">Engine</a> methods <code>createView</code> and <c
 </li>
 <li><strong>onFetched</strong>
 <ul>
-<li>optional callback that&#x27;s invoked after each asset is downloaded.</li>
+<li>optional callback that's invoked after each asset is downloaded.</li>
 </ul>
 </li>
 </ul>
@@ -1001,7 +1001,7 @@ useful for compressed textures. For example, some platforms accept ETC and other
 <ul>
 <li><strong>assets</strong>
 <ul>
-<li>Array of strings containing URL&#x27;s of required assets.</li>
+<li>Array of strings containing URL's of required assets.</li>
 </ul>
 </li>
 <li><strong>onready</strong>
@@ -1010,12 +1010,12 @@ useful for compressed textures. For example, some platforms accept ETC and other
 </ul>
 </li>
 </ul>
-<p>All JavaScript clients must call the init function, passing in a list of asset URL&#x27;s and a
+<p>All JavaScript clients must call the init function, passing in a list of asset URL's and a
 callback. This callback gets invoked only after all assets have been downloaded and the Filament
-WebAssembly module has been loaded. Clients should only pass asset URL&#x27;s that absolutely must
+WebAssembly module has been loaded. Clients should only pass asset URL's that absolutely must
 be ready at initialization time.
 When the callback is called, each downloaded asset is available in the <code>Filament.assets</code> global
-object, which contains a mapping from URL&#x27;s to Uint8Array objects.</p>
+object, which contains a mapping from URL's to Uint8Array objects.</p>
 </div>
 <div class='funcdoc'>
 <h2>function <a id='loadMathExtensions' href='#loadMathExtensions'>loadMathExtensions</a>()</h2>

docs/webgl/tutorial_redball.html

@@ -10,7 +10,7 @@
 textures.</p>
 <p>For starters, create a text file called <code>redball.html</code> and copy over the HTML that we used in the
 <a href="tutorial_triangle.html">previous tutorial</a>. Change the last script tag from <code>triangle.js</code> to <code>redball.js</code>.</p>
-<p>Next you&#x27;ll need to get a couple command-line tools: <code>matc</code> and <code>cmgen</code>. You can find these in the
+<p>Next you'll need to get a couple command-line tools: <code>matc</code> and <code>cmgen</code>. You can find these in the
 appropriate <a href="//github.com/google/filament/releases">Filament release</a>. You should choose the
 archive that corresponds to your development machine rather than the one for web, and the version
 that matches the <code>unpkg.com/filament@x.x.x</code> url in the script tag of <code>redball.html</code> (you may check
@@ -19,7 +19,7 @@ out the last available release of <a href="https://www.npmjs.com/package/filamen
 <p>The <code>matc</code> tool consumes a text file containing a high-level description of a PBR material, and
 produces a binary material package that contains shader code and associated metadata. For more
 information, see the official document describing the <a href="https://google.github.io/filament/Materials.md.html">Filament Material System</a>.</p>
-<p>Let&#x27;s try out <code>matc</code>. Create the following file in your favorite text editor and call it
+<p>Let's try out <code>matc</code>. Create the following file in your favorite text editor and call it
 <code>plastic.mat</code>.</p>
 <div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span>material {
     name : Lit,
@@ -44,16 +44,16 @@ fragment {
 </pre></div>
 
 <p>Next, invoke <code>matc</code> as follows.</p>
-<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span>matc -a opengl -p mobile -o plastic.filamat plastic.mat
+<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span>matc<span style="color: #BBB"> </span>-a<span style="color: #BBB"> </span>opengl<span style="color: #BBB"> </span>-p<span style="color: #BBB"> </span>mobile<span style="color: #BBB"> </span>-o<span style="color: #BBB"> </span>plastic.filamat<span style="color: #BBB"> </span>plastic.mat
 </pre></div>
 
-<p>You should now have a material archive in your working directory, which we&#x27;ll use later in the
+<p>You should now have a material archive in your working directory, which we'll use later in the
 tutorial.</p>
 <h2>Bake environment map</h2>
-<p>Next we&#x27;ll use Filament&#x27;s <code>cmgen</code> tool to consume a HDR environment map in latlong format, and
+<p>Next we'll use Filament's <code>cmgen</code> tool to consume a HDR environment map in latlong format, and
 produce two cubemap files: a mipmapped IBL and a blurry skybox.</p>
 <p>Download <a href="//github.com/google/filament/blob/main/third_party/environments/pillars_2k.hdr">pillars_2k.hdr</a>, then invoke the following command in your terminal.</p>
-<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span>cmgen -x pillars_2k --format<span style="color: #666666">=</span>ktx --size<span style="color: #666666">=256</span> --extract-blur<span style="color: #666666">=0</span>.1 pillars_2k.hdr
+<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span>cmgen<span style="color: #BBB"> </span>-x<span style="color: #BBB"> </span>pillars_2k<span style="color: #BBB"> </span>--format<span style="color: #666">=</span>ktx<span style="color: #BBB"> </span>--size<span style="color: #666">=256</span><span style="color: #BBB"> </span>--extract-blur<span style="color: #666">=0</span>.1<span style="color: #BBB"> </span>pillars_2k.hdr
 </pre></div>
 
 <p>You should now have a <code>pillars_2k</code> folder containing a couple KTX files for the IBL and skybox, as
@@ -61,84 +61,84 @@ well as a text file with spherical harmonics coefficients. You can discard the t
 IBL KTX contains these coefficients in its metadata.</p>
 <h2>Create JavaScript</h2>
 <p>Next, create <code>redball.js</code> with the following content.</p>
-<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>environ<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #BA2121">&#39;pillars_2k&#39;</span>;<span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>ibl_url<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #BA2121">`</span><span style="color: #A45A77; font-weight: bold">${</span>environ<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">/</span><span style="color: #A45A77; font-weight: bold">${</span>environ<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">_ibl.ktx`</span>;<span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>sky_url<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #BA2121">`</span><span style="color: #A45A77; font-weight: bold">${</span>environ<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">/</span><span style="color: #A45A77; font-weight: bold">${</span>environ<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">_skybox.ktx`</span>;<span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>filamat_url<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #BA2121">&#39;plastic.filamat&#39;</span><span style="color: #bbbbbb"></span>
+<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>environ<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #BA2121">&#39;pillars_2k&#39;</span>;
+<span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>ibl_url<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #BA2121">`</span><span style="color: #A45A77; font-weight: bold">${</span>environ<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">/</span><span style="color: #A45A77; font-weight: bold">${</span>environ<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">_ibl.ktx`</span>;
+<span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>sky_url<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #BA2121">`</span><span style="color: #A45A77; font-weight: bold">${</span>environ<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">/</span><span style="color: #A45A77; font-weight: bold">${</span>environ<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">_skybox.ktx`</span>;
+<span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>filamat_url<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #BA2121">&#39;plastic.filamat&#39;</span>
 
-Filament.init([<span style="color: #bbbbbb"> </span>filamat_url,<span style="color: #bbbbbb"> </span>ibl_url,<span style="color: #bbbbbb"> </span>sky_url<span style="color: #bbbbbb"> </span>],<span style="color: #bbbbbb"> </span>()<span style="color: #bbbbbb"> </span>=&gt;<span style="color: #bbbbbb"> </span>{<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span><span style="color: #3D7B7B; font-style: italic">// Create some global aliases to enums for convenience.</span><span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span><span style="color: #008000">window</span>.VertexAttribute<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>Filament.VertexAttribute;<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span><span style="color: #008000">window</span>.AttributeType<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>Filament.VertexBuffer$AttributeType;<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span><span style="color: #008000">window</span>.PrimitiveType<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>Filament.RenderableManager$PrimitiveType;<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span><span style="color: #008000">window</span>.IndexType<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>Filament.IndexBuffer$IndexType;<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span><span style="color: #008000">window</span>.Fov<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>Filament.Camera$Fov;<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span><span style="color: #008000">window</span>.LightType<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>Filament.LightManager$Type;<span style="color: #bbbbbb"></span>
+Filament.init([<span style="color: #BBB"> </span>filamat_url,<span style="color: #BBB"> </span>ibl_url,<span style="color: #BBB"> </span>sky_url<span style="color: #BBB"> </span>],<span style="color: #BBB"> </span>()<span style="color: #BBB"> </span>=&gt;<span style="color: #BBB"> </span>{
+<span style="color: #BBB">  </span><span style="color: #3D7B7B; font-style: italic">// Create some global aliases to enums for convenience.</span>
+<span style="color: #BBB">  </span><span style="color: #008000">window</span>.VertexAttribute<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>Filament.VertexAttribute;
+<span style="color: #BBB">  </span><span style="color: #008000">window</span>.AttributeType<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>Filament.VertexBuffer$AttributeType;
+<span style="color: #BBB">  </span><span style="color: #008000">window</span>.PrimitiveType<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>Filament.RenderableManager$PrimitiveType;
+<span style="color: #BBB">  </span><span style="color: #008000">window</span>.IndexType<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>Filament.IndexBuffer$IndexType;
+<span style="color: #BBB">  </span><span style="color: #008000">window</span>.Fov<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>Filament.Camera$Fov;
+<span style="color: #BBB">  </span><span style="color: #008000">window</span>.LightType<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>Filament.LightManager$Type;
 
-<span style="color: #bbbbbb">  </span><span style="color: #3D7B7B; font-style: italic">// Obtain the canvas DOM object and pass it to the App.</span><span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>canvas<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000">document</span>.getElementsByTagName(<span style="color: #BA2121">&#39;canvas&#39;</span>)[<span style="color: #666666">0</span>];<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span><span style="color: #008000">window</span>.app<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #AA22FF; font-weight: bold">new</span><span style="color: #bbbbbb"> </span>App(canvas);<span style="color: #bbbbbb"></span>
-}<span style="color: #bbbbbb"> </span>);<span style="color: #bbbbbb"></span>
+<span style="color: #BBB">  </span><span style="color: #3D7B7B; font-style: italic">// Obtain the canvas DOM object and pass it to the App.</span>
+<span style="color: #BBB">  </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>canvas<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #008000">document</span>.getElementsByTagName(<span style="color: #BA2121">&#39;canvas&#39;</span>)[<span style="color: #666">0</span>];
+<span style="color: #BBB">  </span><span style="color: #008000">window</span>.app<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #A2F; font-weight: bold">new</span><span style="color: #BBB"> </span>App(canvas);
+}<span style="color: #BBB"> </span>);
 
-<span style="color: #008000; font-weight: bold">class</span><span style="color: #bbbbbb"> </span>App<span style="color: #bbbbbb"> </span>{<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span><span style="color: #008000; font-weight: bold">constructor</span>(canvas)<span style="color: #bbbbbb"> </span>{<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #008000; font-weight: bold">this</span>.canvas<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>canvas;<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>engine<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.engine<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>Filament.Engine.create(canvas);<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>scene<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>engine.createScene();<span style="color: #bbbbbb"></span>
+<span style="color: #008000; font-weight: bold">class</span><span style="color: #BBB"> </span>App<span style="color: #BBB"> </span>{
+<span style="color: #BBB">  </span><span style="color: #008000; font-weight: bold">constructor</span>(canvas)<span style="color: #BBB"> </span>{
+<span style="color: #BBB">    </span><span style="color: #008000; font-weight: bold">this</span>.canvas<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>canvas;
+<span style="color: #BBB">    </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>engine<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #008000; font-weight: bold">this</span>.engine<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>Filament.Engine.create(canvas);
+<span style="color: #BBB">    </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>scene<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>engine.createScene();
 
-<span style="color: #bbbbbb">    </span><span style="color: #3D7B7B; font-style: italic">// TODO: create material</span><span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #3D7B7B; font-style: italic">// TODO: create sphere</span><span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #3D7B7B; font-style: italic">// TODO: create lights</span><span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #3D7B7B; font-style: italic">// TODO: create IBL</span><span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #3D7B7B; font-style: italic">// TODO: create skybox</span><span style="color: #bbbbbb"></span>
+<span style="color: #BBB">    </span><span style="color: #3D7B7B; font-style: italic">// TODO: create material</span>
+<span style="color: #BBB">    </span><span style="color: #3D7B7B; font-style: italic">// TODO: create sphere</span>
+<span style="color: #BBB">    </span><span style="color: #3D7B7B; font-style: italic">// TODO: create lights</span>
+<span style="color: #BBB">    </span><span style="color: #3D7B7B; font-style: italic">// TODO: create IBL</span>
+<span style="color: #BBB">    </span><span style="color: #3D7B7B; font-style: italic">// TODO: create skybox</span>
 
-<span style="color: #bbbbbb">    </span><span style="color: #008000; font-weight: bold">this</span>.swapChain<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>engine.createSwapChain();<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #008000; font-weight: bold">this</span>.renderer<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>engine.createRenderer();<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #008000; font-weight: bold">this</span>.camera<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>engine.createCamera(Filament.EntityManager.get().create());<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #008000; font-weight: bold">this</span>.view<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>engine.createView();<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #008000; font-weight: bold">this</span>.view.setCamera(<span style="color: #008000; font-weight: bold">this</span>.camera);<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #008000; font-weight: bold">this</span>.view.setScene(scene);<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #008000; font-weight: bold">this</span>.resize();<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #008000; font-weight: bold">this</span>.render<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.render.bind(<span style="color: #008000; font-weight: bold">this</span>);<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #008000; font-weight: bold">this</span>.resize<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.resize.bind(<span style="color: #008000; font-weight: bold">this</span>);<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #008000">window</span>.addEventListener(<span style="color: #BA2121">&#39;resize&#39;</span>,<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.resize);<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #008000">window</span>.requestAnimationFrame(<span style="color: #008000; font-weight: bold">this</span>.render);<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span>}<span style="color: #bbbbbb"></span>
+<span style="color: #BBB">    </span><span style="color: #008000; font-weight: bold">this</span>.swapChain<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>engine.createSwapChain();
+<span style="color: #BBB">    </span><span style="color: #008000; font-weight: bold">this</span>.renderer<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>engine.createRenderer();
+<span style="color: #BBB">    </span><span style="color: #008000; font-weight: bold">this</span>.camera<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>engine.createCamera(Filament.EntityManager.get().create());
+<span style="color: #BBB">    </span><span style="color: #008000; font-weight: bold">this</span>.view<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>engine.createView();
+<span style="color: #BBB">    </span><span style="color: #008000; font-weight: bold">this</span>.view.setCamera(<span style="color: #008000; font-weight: bold">this</span>.camera);
+<span style="color: #BBB">    </span><span style="color: #008000; font-weight: bold">this</span>.view.setScene(scene);
+<span style="color: #BBB">    </span><span style="color: #008000; font-weight: bold">this</span>.resize();
+<span style="color: #BBB">    </span><span style="color: #008000; font-weight: bold">this</span>.render<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #008000; font-weight: bold">this</span>.render.bind(<span style="color: #008000; font-weight: bold">this</span>);
+<span style="color: #BBB">    </span><span style="color: #008000; font-weight: bold">this</span>.resize<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #008000; font-weight: bold">this</span>.resize.bind(<span style="color: #008000; font-weight: bold">this</span>);
+<span style="color: #BBB">    </span><span style="color: #008000">window</span>.addEventListener(<span style="color: #BA2121">&#39;resize&#39;</span>,<span style="color: #BBB"> </span><span style="color: #008000; font-weight: bold">this</span>.resize);
+<span style="color: #BBB">    </span><span style="color: #008000">window</span>.requestAnimationFrame(<span style="color: #008000; font-weight: bold">this</span>.render);
+<span style="color: #BBB">  </span>}
 
-<span style="color: #bbbbbb">  </span>render()<span style="color: #bbbbbb"> </span>{<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>eye<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>[<span style="color: #666666">0</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">0</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">4</span>],<span style="color: #bbbbbb"> </span>center<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>[<span style="color: #666666">0</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">0</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">0</span>],<span style="color: #bbbbbb"> </span>up<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>[<span style="color: #666666">0</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">1</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">0</span>];<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>radians<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000">Date</span>.now()<span style="color: #bbbbbb"> </span><span style="color: #666666">/</span><span style="color: #bbbbbb"> </span><span style="color: #666666">10000</span>;<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span>vec3.rotateY(eye,<span style="color: #bbbbbb"> </span>eye,<span style="color: #bbbbbb"> </span>center,<span style="color: #bbbbbb"> </span>radians);<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #008000; font-weight: bold">this</span>.camera.lookAt(eye,<span style="color: #bbbbbb"> </span>center,<span style="color: #bbbbbb"> </span>up);<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #008000; font-weight: bold">this</span>.renderer.render(<span style="color: #008000; font-weight: bold">this</span>.swapChain,<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.view);<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #008000">window</span>.requestAnimationFrame(<span style="color: #008000; font-weight: bold">this</span>.render);<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span>}<span style="color: #bbbbbb"></span>
+<span style="color: #BBB">  </span>render()<span style="color: #BBB"> </span>{
+<span style="color: #BBB">    </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>eye<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>[<span style="color: #666">0</span>,<span style="color: #BBB"> </span><span style="color: #666">0</span>,<span style="color: #BBB"> </span><span style="color: #666">4</span>],<span style="color: #BBB"> </span>center<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>[<span style="color: #666">0</span>,<span style="color: #BBB"> </span><span style="color: #666">0</span>,<span style="color: #BBB"> </span><span style="color: #666">0</span>],<span style="color: #BBB"> </span>up<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>[<span style="color: #666">0</span>,<span style="color: #BBB"> </span><span style="color: #666">1</span>,<span style="color: #BBB"> </span><span style="color: #666">0</span>];
+<span style="color: #BBB">    </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>radians<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #008000">Date</span>.now()<span style="color: #BBB"> </span><span style="color: #666">/</span><span style="color: #BBB"> </span><span style="color: #666">10000</span>;
+<span style="color: #BBB">    </span>vec3.rotateY(eye,<span style="color: #BBB"> </span>eye,<span style="color: #BBB"> </span>center,<span style="color: #BBB"> </span>radians);
+<span style="color: #BBB">    </span><span style="color: #008000; font-weight: bold">this</span>.camera.lookAt(eye,<span style="color: #BBB"> </span>center,<span style="color: #BBB"> </span>up);
+<span style="color: #BBB">    </span><span style="color: #008000; font-weight: bold">this</span>.renderer.render(<span style="color: #008000; font-weight: bold">this</span>.swapChain,<span style="color: #BBB"> </span><span style="color: #008000; font-weight: bold">this</span>.view);
+<span style="color: #BBB">    </span><span style="color: #008000">window</span>.requestAnimationFrame(<span style="color: #008000; font-weight: bold">this</span>.render);
+<span style="color: #BBB">  </span>}
 
-<span style="color: #bbbbbb">  </span>resize()<span style="color: #bbbbbb"> </span>{<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>dpr<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000">window</span>.devicePixelRatio;<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>width<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.canvas.width<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000">window</span>.innerWidth<span style="color: #bbbbbb"> </span><span style="color: #666666">*</span><span style="color: #bbbbbb"> </span>dpr;<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>height<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.canvas.height<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000">window</span>.innerHeight<span style="color: #bbbbbb"> </span><span style="color: #666666">*</span><span style="color: #bbbbbb"> </span>dpr;<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #008000; font-weight: bold">this</span>.view.setViewport([<span style="color: #666666">0</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">0</span>,<span style="color: #bbbbbb"> </span>width,<span style="color: #bbbbbb"> </span>height]);<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #008000; font-weight: bold">this</span>.camera.setProjectionFov(<span style="color: #666666">45</span>,<span style="color: #bbbbbb"> </span>width<span style="color: #bbbbbb"> </span><span style="color: #666666">/</span><span style="color: #bbbbbb"> </span>height,<span style="color: #bbbbbb"> </span><span style="color: #666666">1.0</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">10.0</span>,<span style="color: #bbbbbb"> </span>Fov.VERTICAL);<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span>}<span style="color: #bbbbbb"></span>
-}<span style="color: #bbbbbb"></span>
+<span style="color: #BBB">  </span>resize()<span style="color: #BBB"> </span>{
+<span style="color: #BBB">    </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>dpr<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #008000">window</span>.devicePixelRatio;
+<span style="color: #BBB">    </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>width<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #008000; font-weight: bold">this</span>.canvas.width<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #008000">window</span>.innerWidth<span style="color: #BBB"> </span><span style="color: #666">*</span><span style="color: #BBB"> </span>dpr;
+<span style="color: #BBB">    </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>height<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #008000; font-weight: bold">this</span>.canvas.height<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #008000">window</span>.innerHeight<span style="color: #BBB"> </span><span style="color: #666">*</span><span style="color: #BBB"> </span>dpr;
+<span style="color: #BBB">    </span><span style="color: #008000; font-weight: bold">this</span>.view.setViewport([<span style="color: #666">0</span>,<span style="color: #BBB"> </span><span style="color: #666">0</span>,<span style="color: #BBB"> </span>width,<span style="color: #BBB"> </span>height]);
+<span style="color: #BBB">    </span><span style="color: #008000; font-weight: bold">this</span>.camera.setProjectionFov(<span style="color: #666">45</span>,<span style="color: #BBB"> </span>width<span style="color: #BBB"> </span><span style="color: #666">/</span><span style="color: #BBB"> </span>height,<span style="color: #BBB"> </span><span style="color: #666">1.0</span>,<span style="color: #BBB"> </span><span style="color: #666">10.0</span>,<span style="color: #BBB"> </span>Fov.VERTICAL);
+<span style="color: #BBB">  </span>}
+}
 </pre></div>
 
 <p>The above boilerplate should be familiar to you from the previous tutorial, although it loads in a
 new set of assets. We also added some animation to the camera.</p>
-<p>Next let&#x27;s create a material instance from the package that we built at the beginning the tutorial.
+<p>Next let's create a material instance from the package that we built at the beginning the tutorial.
 Replace the <strong>create material</strong> comment with the following snippet.</p>
-<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>material<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>engine.createMaterial(filamat_url);<span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>matinstance<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>material.createInstance();<span style="color: #bbbbbb"></span>
+<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>material<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>engine.createMaterial(filamat_url);
+<span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>matinstance<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>material.createInstance();
 
-<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>red<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>[<span style="color: #666666">0.8</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">0.0</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">0.0</span>];<span style="color: #bbbbbb"></span>
-matinstance.setColor3Parameter(<span style="color: #BA2121">&#39;baseColor&#39;</span>,<span style="color: #bbbbbb"> </span>Filament.RgbType.sRGB,<span style="color: #bbbbbb"> </span>red);<span style="color: #bbbbbb"></span>
-matinstance.setFloatParameter(<span style="color: #BA2121">&#39;roughness&#39;</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">0.5</span>);<span style="color: #bbbbbb"></span>
-matinstance.setFloatParameter(<span style="color: #BA2121">&#39;clearCoat&#39;</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">1.0</span>);<span style="color: #bbbbbb"></span>
-matinstance.setFloatParameter(<span style="color: #BA2121">&#39;clearCoatRoughness&#39;</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">0.3</span>);<span style="color: #bbbbbb"></span>
+<span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>red<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>[<span style="color: #666">0.8</span>,<span style="color: #BBB"> </span><span style="color: #666">0.0</span>,<span style="color: #BBB"> </span><span style="color: #666">0.0</span>];
+matinstance.setColor3Parameter(<span style="color: #BA2121">&#39;baseColor&#39;</span>,<span style="color: #BBB"> </span>Filament.RgbType.sRGB,<span style="color: #BBB"> </span>red);
+matinstance.setFloatParameter(<span style="color: #BA2121">&#39;roughness&#39;</span>,<span style="color: #BBB"> </span><span style="color: #666">0.5</span>);
+matinstance.setFloatParameter(<span style="color: #BA2121">&#39;clearCoat&#39;</span>,<span style="color: #BBB"> </span><span style="color: #666">1.0</span>);
+matinstance.setFloatParameter(<span style="color: #BA2121">&#39;clearCoatRoughness&#39;</span>,<span style="color: #BBB"> </span><span style="color: #666">0.3</span>);
 </pre></div>
 
-<p>The next step is to create a renderable for the sphere. To help with this, we&#x27;ll use the <code>IcoSphere</code>
+<p>The next step is to create a renderable for the sphere. To help with this, we'll use the <code>IcoSphere</code>
 utility class, whose constructor takes a LOD. Its job is to subdivide an icosadedron, producing
 three arrays:</p>
 <ul>
@@ -147,137 +147,137 @@ three arrays:</p>
 as quaternions.</li>
 <li><code>icosphere.triangles</code> Uint16Array with triangle indices.</li>
 </ul>
-<p>Let&#x27;s go ahead use these arrays to build the vertex buffer and index buffer. Replace <strong>create
+<p>Let's go ahead use these arrays to build the vertex buffer and index buffer. Replace <strong>create
 sphere</strong> with the following snippet.</p>
-<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>renderable<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>Filament.EntityManager.get().create();<span style="color: #bbbbbb"></span>
-scene.addEntity(renderable);<span style="color: #bbbbbb"></span>
+<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>renderable<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>Filament.EntityManager.get().create();
+scene.addEntity(renderable);
 
-<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>icosphere<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #AA22FF; font-weight: bold">new</span><span style="color: #bbbbbb"> </span>Filament.IcoSphere(<span style="color: #666666">5</span>);<span style="color: #bbbbbb"></span>
+<span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>icosphere<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #A2F; font-weight: bold">new</span><span style="color: #BBB"> </span>Filament.IcoSphere(<span style="color: #666">5</span>);
 
-<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>vb<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>Filament.VertexBuffer.Builder()<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span>.vertexCount(icosphere.vertices.length<span style="color: #bbbbbb"> </span><span style="color: #666666">/</span><span style="color: #bbbbbb"> </span><span style="color: #666666">3</span>)<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span>.bufferCount(<span style="color: #666666">2</span>)<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span>.attribute(VertexAttribute.POSITION,<span style="color: #bbbbbb"> </span><span style="color: #666666">0</span>,<span style="color: #bbbbbb"> </span>AttributeType.FLOAT3,<span style="color: #bbbbbb"> </span><span style="color: #666666">0</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">0</span>)<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span>.attribute(VertexAttribute.TANGENTS,<span style="color: #bbbbbb"> </span><span style="color: #666666">1</span>,<span style="color: #bbbbbb"> </span>AttributeType.SHORT4,<span style="color: #bbbbbb"> </span><span style="color: #666666">0</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">0</span>)<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span>.normalized(VertexAttribute.TANGENTS)<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span>.build(engine);<span style="color: #bbbbbb"></span>
+<span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>vb<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>Filament.VertexBuffer.Builder()
+<span style="color: #BBB">  </span>.vertexCount(icosphere.vertices.length<span style="color: #BBB"> </span><span style="color: #666">/</span><span style="color: #BBB"> </span><span style="color: #666">3</span>)
+<span style="color: #BBB">  </span>.bufferCount(<span style="color: #666">2</span>)
+<span style="color: #BBB">  </span>.attribute(VertexAttribute.POSITION,<span style="color: #BBB"> </span><span style="color: #666">0</span>,<span style="color: #BBB"> </span>AttributeType.FLOAT3,<span style="color: #BBB"> </span><span style="color: #666">0</span>,<span style="color: #BBB"> </span><span style="color: #666">0</span>)
+<span style="color: #BBB">  </span>.attribute(VertexAttribute.TANGENTS,<span style="color: #BBB"> </span><span style="color: #666">1</span>,<span style="color: #BBB"> </span>AttributeType.SHORT4,<span style="color: #BBB"> </span><span style="color: #666">0</span>,<span style="color: #BBB"> </span><span style="color: #666">0</span>)
+<span style="color: #BBB">  </span>.normalized(VertexAttribute.TANGENTS)
+<span style="color: #BBB">  </span>.build(engine);
 
-<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>ib<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>Filament.IndexBuffer.Builder()<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span>.indexCount(icosphere.triangles.length)<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span>.bufferType(IndexType.USHORT)<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span>.build(engine);<span style="color: #bbbbbb"></span>
+<span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>ib<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>Filament.IndexBuffer.Builder()
+<span style="color: #BBB">  </span>.indexCount(icosphere.triangles.length)
+<span style="color: #BBB">  </span>.bufferType(IndexType.USHORT)
+<span style="color: #BBB">  </span>.build(engine);
 
-vb.setBufferAt(engine,<span style="color: #bbbbbb"> </span><span style="color: #666666">0</span>,<span style="color: #bbbbbb"> </span>icosphere.vertices);<span style="color: #bbbbbb"></span>
-vb.setBufferAt(engine,<span style="color: #bbbbbb"> </span><span style="color: #666666">1</span>,<span style="color: #bbbbbb"> </span>icosphere.tangents);<span style="color: #bbbbbb"></span>
-ib.setBuffer(engine,<span style="color: #bbbbbb"> </span>icosphere.triangles);<span style="color: #bbbbbb"></span>
+vb.setBufferAt(engine,<span style="color: #BBB"> </span><span style="color: #666">0</span>,<span style="color: #BBB"> </span>icosphere.vertices);
+vb.setBufferAt(engine,<span style="color: #BBB"> </span><span style="color: #666">1</span>,<span style="color: #BBB"> </span>icosphere.tangents);
+ib.setBuffer(engine,<span style="color: #BBB"> </span>icosphere.triangles);
 
-Filament.RenderableManager.Builder(<span style="color: #666666">1</span>)<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span>.boundingBox({<span style="color: #bbbbbb"> </span>center<span style="color: #666666">:</span><span style="color: #bbbbbb"> </span>[<span style="color: #666666">-1</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">-1</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">-1</span>],<span style="color: #bbbbbb"> </span>halfExtent<span style="color: #666666">:</span><span style="color: #bbbbbb"> </span>[<span style="color: #666666">1</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">1</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">1</span>]<span style="color: #bbbbbb"> </span>})<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span>.material(<span style="color: #666666">0</span>,<span style="color: #bbbbbb"> </span>matinstance)<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span>.geometry(<span style="color: #666666">0</span>,<span style="color: #bbbbbb"> </span>PrimitiveType.TRIANGLES,<span style="color: #bbbbbb"> </span>vb,<span style="color: #bbbbbb"> </span>ib)<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span>.build(engine,<span style="color: #bbbbbb"> </span>renderable);<span style="color: #bbbbbb"></span>
+Filament.RenderableManager.Builder(<span style="color: #666">1</span>)
+<span style="color: #BBB">  </span>.boundingBox({<span style="color: #BBB"> </span>center<span style="color: #666">:</span><span style="color: #BBB"> </span>[<span style="color: #666">-1</span>,<span style="color: #BBB"> </span><span style="color: #666">-1</span>,<span style="color: #BBB"> </span><span style="color: #666">-1</span>],<span style="color: #BBB"> </span>halfExtent<span style="color: #666">:</span><span style="color: #BBB"> </span>[<span style="color: #666">1</span>,<span style="color: #BBB"> </span><span style="color: #666">1</span>,<span style="color: #BBB"> </span><span style="color: #666">1</span>]<span style="color: #BBB"> </span>})
+<span style="color: #BBB">  </span>.material(<span style="color: #666">0</span>,<span style="color: #BBB"> </span>matinstance)
+<span style="color: #BBB">  </span>.geometry(<span style="color: #666">0</span>,<span style="color: #BBB"> </span>PrimitiveType.TRIANGLES,<span style="color: #BBB"> </span>vb,<span style="color: #BBB"> </span>ib)
+<span style="color: #BBB">  </span>.build(engine,<span style="color: #BBB"> </span>renderable);
 </pre></div>
 
-<p>At this point, the app is rendering a sphere, but it is black so it doesn&#x27;t show up. To prove that
+<p>At this point, the app is rendering a sphere, but it is black so it doesn't show up. To prove that
 the sphere is there, you can try changing the background color to blue via <code>setClearColor</code>, like we
 did in the first tutorial.</p>
 <h2>Add lighting</h2>
 <p>In this section we will create some directional light sources, as well as an image-based light (IBL)
 defined by one of the KTX files we built at the start of the demo. First, replace the <strong>create
 lights</strong> comment with the following snippet.</p>
-<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>sunlight<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>Filament.EntityManager.get().create();<span style="color: #bbbbbb"></span>
-scene.addEntity(sunlight);<span style="color: #bbbbbb"></span>
-Filament.LightManager.Builder(LightType.SUN)<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span>.color([<span style="color: #666666">0.98</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">0.92</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">0.89</span>])<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span>.intensity(<span style="color: #666666">110000.0</span>)<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span>.direction([<span style="color: #666666">0.6</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">-1.0</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">-0.8</span>])<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span>.sunAngularRadius(<span style="color: #666666">1.9</span>)<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span>.sunHaloSize(<span style="color: #666666">10.0</span>)<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span>.sunHaloFalloff(<span style="color: #666666">80.0</span>)<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span>.build(engine,<span style="color: #bbbbbb"> </span>sunlight);<span style="color: #bbbbbb"></span>
+<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>sunlight<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>Filament.EntityManager.get().create();
+scene.addEntity(sunlight);
+Filament.LightManager.Builder(LightType.SUN)
+<span style="color: #BBB">  </span>.color([<span style="color: #666">0.98</span>,<span style="color: #BBB"> </span><span style="color: #666">0.92</span>,<span style="color: #BBB"> </span><span style="color: #666">0.89</span>])
+<span style="color: #BBB">  </span>.intensity(<span style="color: #666">110000.0</span>)
+<span style="color: #BBB">  </span>.direction([<span style="color: #666">0.6</span>,<span style="color: #BBB"> </span><span style="color: #666">-1.0</span>,<span style="color: #BBB"> </span><span style="color: #666">-0.8</span>])
+<span style="color: #BBB">  </span>.sunAngularRadius(<span style="color: #666">1.9</span>)
+<span style="color: #BBB">  </span>.sunHaloSize(<span style="color: #666">10.0</span>)
+<span style="color: #BBB">  </span>.sunHaloFalloff(<span style="color: #666">80.0</span>)
+<span style="color: #BBB">  </span>.build(engine,<span style="color: #BBB"> </span>sunlight);
 
-<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>backlight<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>Filament.EntityManager.get().create();<span style="color: #bbbbbb"></span>
-scene.addEntity(backlight);<span style="color: #bbbbbb"></span>
-Filament.LightManager.Builder(LightType.DIRECTIONAL)<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">        </span>.direction([<span style="color: #666666">-1</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">0</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">1</span>])<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">        </span>.intensity(<span style="color: #666666">50000.0</span>)<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">        </span>.build(engine,<span style="color: #bbbbbb"> </span>backlight);<span style="color: #bbbbbb"></span>
+<span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>backlight<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>Filament.EntityManager.get().create();
+scene.addEntity(backlight);
+Filament.LightManager.Builder(LightType.DIRECTIONAL)
+<span style="color: #BBB">        </span>.direction([<span style="color: #666">-1</span>,<span style="color: #BBB"> </span><span style="color: #666">0</span>,<span style="color: #BBB"> </span><span style="color: #666">1</span>])
+<span style="color: #BBB">        </span>.intensity(<span style="color: #666">50000.0</span>)
+<span style="color: #BBB">        </span>.build(engine,<span style="color: #BBB"> </span>backlight);
 </pre></div>
 
 <p>The <code>SUN</code> light source is similar to the <code>DIRECTIONAL</code> light source, but has some extra
 parameters because Filament will automatically draw a disk into the skybox.</p>
 <p>Next we need to create an <code>IndirectLight</code> object from the KTX IBL. One way of doing this is the
-following (don&#x27;t type this out, there&#x27;s an easier way).</p>
-<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>format<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>Filament.PixelDataFormat.RGB;<span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>datatype<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>Filament.PixelDataType.UINT_10F_11F_11F_REV;<span style="color: #bbbbbb"></span>
+following (don't type this out, there's an easier way).</p>
+<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>format<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>Filament.PixelDataFormat.RGB;
+<span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>datatype<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>Filament.PixelDataType.UINT_10F_11F_11F_REV;
 
-<span style="color: #3D7B7B; font-style: italic">// Create a Texture object for the mipmapped cubemap.</span><span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>ibl_package<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>Filament.Buffer(Filament.assets[ibl_url]);<span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>iblktx<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #AA22FF; font-weight: bold">new</span><span style="color: #bbbbbb"> </span>Filament.Ktx1Bundle(ibl_package);<span style="color: #bbbbbb"></span>
+<span style="color: #3D7B7B; font-style: italic">// Create a Texture object for the mipmapped cubemap.</span>
+<span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>ibl_package<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>Filament.Buffer(Filament.assets[ibl_url]);
+<span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>iblktx<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #A2F; font-weight: bold">new</span><span style="color: #BBB"> </span>Filament.Ktx1Bundle(ibl_package);
 
-<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>ibltex<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>Filament.Texture.Builder()<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span>.width(iblktx.info().pixelWidth)<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span>.height(iblktx.info().pixelHeight)<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span>.levels(iblktx.getNumMipLevels())<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span>.sampler(Filament.Texture$Sampler.SAMPLER_CUBEMAP)<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span>.format(Filament.Texture$InternalFormat.RGBA8)<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span>.build(engine);<span style="color: #bbbbbb"></span>
+<span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>ibltex<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>Filament.Texture.Builder()
+<span style="color: #BBB">  </span>.width(iblktx.info().pixelWidth)
+<span style="color: #BBB">  </span>.height(iblktx.info().pixelHeight)
+<span style="color: #BBB">  </span>.levels(iblktx.getNumMipLevels())
+<span style="color: #BBB">  </span>.sampler(Filament.Texture$Sampler.SAMPLER_CUBEMAP)
+<span style="color: #BBB">  </span>.format(Filament.Texture$InternalFormat.RGBA8)
+<span style="color: #BBB">  </span>.build(engine);
 
-<span style="color: #008000; font-weight: bold">for</span><span style="color: #bbbbbb"> </span>(<span style="color: #008000; font-weight: bold">let</span><span style="color: #bbbbbb"> </span>level<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #666666">0</span>;<span style="color: #bbbbbb"> </span>level<span style="color: #bbbbbb"> </span><span style="color: #666666">&lt;</span><span style="color: #bbbbbb"> </span>iblktx.getNumMipLevels();<span style="color: #bbbbbb"> </span><span style="color: #666666">++</span>level)<span style="color: #bbbbbb"> </span>{<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>uint8array<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>iblktx.getCubeBlob(level).getBytes();<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>pixelbuffer<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>Filament.PixelBuffer(uint8array,<span style="color: #bbbbbb"> </span>format,<span style="color: #bbbbbb"> </span>datatype);<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span>ibltex.setImageCube(engine,<span style="color: #bbbbbb"> </span>level,<span style="color: #bbbbbb"> </span>pixelbuffer);<span style="color: #bbbbbb"></span>
-}<span style="color: #bbbbbb"></span>
+<span style="color: #008000; font-weight: bold">for</span><span style="color: #BBB"> </span>(<span style="color: #008000; font-weight: bold">let</span><span style="color: #BBB"> </span>level<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #666">0</span>;<span style="color: #BBB"> </span>level<span style="color: #BBB"> </span><span style="color: #666">&lt;</span><span style="color: #BBB"> </span>iblktx.getNumMipLevels();<span style="color: #BBB"> </span><span style="color: #666">++</span>level)<span style="color: #BBB"> </span>{
+<span style="color: #BBB">  </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>uint8array<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>iblktx.getCubeBlob(level).getBytes();
+<span style="color: #BBB">  </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>pixelbuffer<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>Filament.PixelBuffer(uint8array,<span style="color: #BBB"> </span>format,<span style="color: #BBB"> </span>datatype);
+<span style="color: #BBB">  </span>ibltex.setImageCube(engine,<span style="color: #BBB"> </span>level,<span style="color: #BBB"> </span>pixelbuffer);
+}
 
-<span style="color: #3D7B7B; font-style: italic">// Parse the spherical harmonics metadata.</span><span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>shstring<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>iblktx.getMetadata(<span style="color: #BA2121">&#39;sh&#39;</span>);<span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>shfloats<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>shstring.split(<span style="color: #A45A77">/\s/</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">9</span><span style="color: #bbbbbb"> </span><span style="color: #666666">*</span><span style="color: #bbbbbb"> </span><span style="color: #666666">3</span>).map(<span style="color: #008000">parseFloat</span>);<span style="color: #bbbbbb"></span>
+<span style="color: #3D7B7B; font-style: italic">// Parse the spherical harmonics metadata.</span>
+<span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>shstring<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>iblktx.getMetadata(<span style="color: #BA2121">&#39;sh&#39;</span>);
+<span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>shfloats<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>shstring.split(<span style="color: #A45A77">/\s/</span>,<span style="color: #BBB"> </span><span style="color: #666">9</span><span style="color: #BBB"> </span><span style="color: #666">*</span><span style="color: #BBB"> </span><span style="color: #666">3</span>).map(<span style="color: #008000">parseFloat</span>);
 
-<span style="color: #3D7B7B; font-style: italic">// Build the IBL object and insert it into the scene.</span><span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>indirectLight<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>Filament.IndirectLight.Builder()<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span>.reflections(ibltex)<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span>.irradianceSh(<span style="color: #666666">3</span>,<span style="color: #bbbbbb"> </span>shfloats)<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span>.intensity(<span style="color: #666666">50000.0</span>)<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span>.build(engine);<span style="color: #bbbbbb"></span>
+<span style="color: #3D7B7B; font-style: italic">// Build the IBL object and insert it into the scene.</span>
+<span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>indirectLight<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>Filament.IndirectLight.Builder()
+<span style="color: #BBB">  </span>.reflections(ibltex)
+<span style="color: #BBB">  </span>.irradianceSh(<span style="color: #666">3</span>,<span style="color: #BBB"> </span>shfloats)
+<span style="color: #BBB">  </span>.intensity(<span style="color: #666">50000.0</span>)
+<span style="color: #BBB">  </span>.build(engine);
 
-scene.setIndirectLight(indirectLight);<span style="color: #bbbbbb"></span>
+scene.setIndirectLight(indirectLight);
 </pre></div>
 
 <p>Filament provides a JavaScript utility to make this simpler,
 simply replace the <strong>create IBL</strong> comment with the following snippet.</p>
-<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>indirectLight<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>engine.createIblFromKtx1(ibl_url);<span style="color: #bbbbbb"></span>
-indirectLight.setIntensity(<span style="color: #666666">50000</span>);<span style="color: #bbbbbb"></span>
-scene.setIndirectLight(indirectLight);<span style="color: #bbbbbb"></span>
+<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>indirectLight<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>engine.createIblFromKtx1(ibl_url);
+indirectLight.setIntensity(<span style="color: #666">50000</span>);
+scene.setIndirectLight(indirectLight);
 </pre></div>
 
 <h2>Add background</h2>
 <p>At this point you can run the demo and you should see a red plastic ball against a black background.
 Without a skybox, the reflections on the ball are not representative of its surroundings.
-Here&#x27;s one way to create a texture for the skybox:</p>
-<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>sky_package<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>Filament.Buffer(Filament.assets[sky_url]);<span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>skyktx<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #AA22FF; font-weight: bold">new</span><span style="color: #bbbbbb"> </span>Filament.Ktx1Bundle(sky_package);<span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>skytex<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>Filament.Texture.Builder()<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span>.width(skyktx.info().pixelWidth)<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span>.height(skyktx.info().pixelHeight)<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span>.levels(<span style="color: #666666">1</span>)<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span>.sampler(Filament.Texture$Sampler.SAMPLER_CUBEMAP)<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span>.format(Filament.Texture$InternalFormat.RGBA8)<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span>.build(engine);<span style="color: #bbbbbb"></span>
+Here's one way to create a texture for the skybox:</p>
+<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>sky_package<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>Filament.Buffer(Filament.assets[sky_url]);
+<span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>skyktx<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #A2F; font-weight: bold">new</span><span style="color: #BBB"> </span>Filament.Ktx1Bundle(sky_package);
+<span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>skytex<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>Filament.Texture.Builder()
+<span style="color: #BBB">  </span>.width(skyktx.info().pixelWidth)
+<span style="color: #BBB">  </span>.height(skyktx.info().pixelHeight)
+<span style="color: #BBB">  </span>.levels(<span style="color: #666">1</span>)
+<span style="color: #BBB">  </span>.sampler(Filament.Texture$Sampler.SAMPLER_CUBEMAP)
+<span style="color: #BBB">  </span>.format(Filament.Texture$InternalFormat.RGBA8)
+<span style="color: #BBB">  </span>.build(engine);
 
-<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>uint8array<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>skyktx.getCubeBlob(<span style="color: #666666">0</span>).getBytes();<span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>pixelbuffer<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>Filament.PixelBuffer(uint8array,<span style="color: #bbbbbb"> </span>format,<span style="color: #bbbbbb"> </span>datatype);<span style="color: #bbbbbb"></span>
-skytex.setImageCube(engine,<span style="color: #bbbbbb"> </span><span style="color: #666666">0</span>,<span style="color: #bbbbbb"> </span>pixelbuffer);<span style="color: #bbbbbb"></span>
+<span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>uint8array<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>skyktx.getCubeBlob(<span style="color: #666">0</span>).getBytes();
+<span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>pixelbuffer<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>Filament.PixelBuffer(uint8array,<span style="color: #BBB"> </span>format,<span style="color: #BBB"> </span>datatype);
+skytex.setImageCube(engine,<span style="color: #BBB"> </span><span style="color: #666">0</span>,<span style="color: #BBB"> </span>pixelbuffer);
 </pre></div>
 
 <p>Filament provides a Javascript utility to make this easier.
 Replace <strong>create skybox</strong> with the following.</p>
-<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>skybox<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>engine.createSkyFromKtx1(sky_url);<span style="color: #bbbbbb"></span>
-scene.setSkybox(skybox);<span style="color: #bbbbbb"></span>
+<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>skybox<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>engine.createSkyFromKtx1(sky_url);
+scene.setSkybox(skybox);
 </pre></div>
 
-<p>That&#x27;s it, we now have a shiny red ball floating in an environment! The complete JavaScript file is
+<p>That's it, we now have a shiny red ball floating in an environment! The complete JavaScript file is
 available <a href="tutorial_redball.js">here</a>.</p>
-<p>In the <a href="tutorial_suzanne.html">next tutorial</a>, we&#x27;ll take a closer look at textures and interaction.</p>
+<p>In the <a href="tutorial_suzanne.html">next tutorial</a>, we'll take a closer look at textures and interaction.</p>
 
 </body>
 </html>

docs/webgl/tutorial_suzanne.html

@@ -8,58 +8,58 @@
 <div class="demo_frame"><iframe src="demo_suzanne.html"></iframe><a href="demo_suzanne.html">&#x1F517;</a></div>
 <p>This tutorial will describe how to create the <strong>suzanne</strong> demo, introducing you to compressed
 textures, mipmap generation, asynchronous texture loading, and trackball rotation.</p>
-<p>Much like the <a href="tutorial_redball.html">previous tutorial</a>, you&#x27;ll need to use the command-line tools that can be found in
+<p>Much like the <a href="tutorial_redball.html">previous tutorial</a>, you'll need to use the command-line tools that can be found in
 the appropriate <a href="//github.com/google/filament/releases">Filament release</a> for your development machine. In addition to <code>matc</code> and <code>cmgen</code>,
-we&#x27;ll also be using <code>filamesh</code> and <code>mipgen</code>.</p>
+we'll also be using <code>filamesh</code> and <code>mipgen</code>.</p>
 <h2>Create filamesh file</h2>
 <p>Filament does not have an asset loading system, but it does provide a binary mesh format
-called <code>filamesh</code> for simple use cases. Let&#x27;s create a compressed filamesh file for suzanne by
+called <code>filamesh</code> for simple use cases. Let's create a compressed filamesh file for suzanne by
 converting <a href="https://github.com/google/filament/blob/main/assets/models/monkey/monkey.obj">this OBJ file</a>:</p>
-<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span>filamesh --compress monkey.obj suzanne.filamesh
+<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span>filamesh<span style="color: #BBB"> </span>--compress<span style="color: #BBB"> </span>monkey.obj<span style="color: #BBB"> </span>suzanne.filamesh
 </pre></div>
 
 <h2>Create mipmapped textures</h2>
-<p>Next, let&#x27;s create mipmapped KTX files using filament&#x27;s <code>mipgen</code> tool. We&#x27;ll create compressed and
+<p>Next, let's create mipmapped KTX files using filament's <code>mipgen</code> tool. We'll create compressed and
 non-compressed variants for each texture, since not all platforms support the same compression
 formats. First copy over the PNG files from the <a href="https://github.com/google/filament/blob/main/assets/models/monkey">monkey folder</a>, then do:</p>
 <div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #3D7B7B; font-style: italic"># Create mipmaps for base color</span>
-mipgen albedo.png albedo.ktx2
-mipgen --compression<span style="color: #666666">=</span>uastc albedo.png albedo.ktx2
+mipgen<span style="color: #BBB"> </span>albedo.png<span style="color: #BBB"> </span>albedo.ktx2
+mipgen<span style="color: #BBB"> </span>--compression<span style="color: #666">=</span>uastc<span style="color: #BBB"> </span>albedo.png<span style="color: #BBB"> </span>albedo.ktx2
 
 <span style="color: #3D7B7B; font-style: italic"># Create mipmaps for the normal map and a compressed variant.</span>
-mipgen --strip-alpha --kernel<span style="color: #666666">=</span>NORMALS --linear normal.png normal.ktx
-mipgen --strip-alpha --kernel<span style="color: #666666">=</span>NORMALS --linear --compression<span style="color: #666666">=</span>uastc_normals <span style="color: #AA5D1F; font-weight: bold">\</span>
-    normal.png normal.ktx2
+mipgen<span style="color: #BBB"> </span>--strip-alpha<span style="color: #BBB"> </span>--kernel<span style="color: #666">=</span>NORMALS<span style="color: #BBB"> </span>--linear<span style="color: #BBB"> </span>normal.png<span style="color: #BBB"> </span>normal.ktx
+mipgen<span style="color: #BBB"> </span>--strip-alpha<span style="color: #BBB"> </span>--kernel<span style="color: #666">=</span>NORMALS<span style="color: #BBB"> </span>--linear<span style="color: #BBB"> </span>--compression<span style="color: #666">=</span>uastc_normals<span style="color: #BBB"> </span><span style="color: #AA5D1F; font-weight: bold">\</span>
+<span style="color: #BBB">    </span>normal.png<span style="color: #BBB"> </span>normal.ktx2
 
 <span style="color: #3D7B7B; font-style: italic"># Create mipmaps for the single-component roughness map and a compressed variant.</span>
-mipgen --grayscale roughness.png roughness.ktx
-mipgen --grayscale --compression<span style="color: #666666">=</span>uastc roughness.png roughness.ktx2
+mipgen<span style="color: #BBB"> </span>--grayscale<span style="color: #BBB"> </span>roughness.png<span style="color: #BBB"> </span>roughness.ktx
+mipgen<span style="color: #BBB"> </span>--grayscale<span style="color: #BBB"> </span>--compression<span style="color: #666">=</span>uastc<span style="color: #BBB"> </span>roughness.png<span style="color: #BBB"> </span>roughness.ktx2
 
 <span style="color: #3D7B7B; font-style: italic"># Create mipmaps for the single-component metallic map and a compressed variant.</span>
-mipgen --grayscale metallic.png metallic.ktx
-mipgen --grayscale --compression<span style="color: #666666">=</span>uastc metallic.png metallic.ktx2
+mipgen<span style="color: #BBB"> </span>--grayscale<span style="color: #BBB"> </span>metallic.png<span style="color: #BBB"> </span>metallic.ktx
+mipgen<span style="color: #BBB"> </span>--grayscale<span style="color: #BBB"> </span>--compression<span style="color: #666">=</span>uastc<span style="color: #BBB"> </span>metallic.png<span style="color: #BBB"> </span>metallic.ktx2
 
 <span style="color: #3D7B7B; font-style: italic"># Create mipmaps for the single-component occlusion map and a compressed variant.</span>
-mipgen --grayscale ao.png ao.ktx
-mipgen --grayscale --compression<span style="color: #666666">=</span>uastc ao.png ao.ktx2
+mipgen<span style="color: #BBB"> </span>--grayscale<span style="color: #BBB"> </span>ao.png<span style="color: #BBB"> </span>ao.ktx
+mipgen<span style="color: #BBB"> </span>--grayscale<span style="color: #BBB"> </span>--compression<span style="color: #666">=</span>uastc<span style="color: #BBB"> </span>ao.png<span style="color: #BBB"> </span>ao.ktx2
 </pre></div>
 
-<p>For more information on mipgen&#x27;s arguments and supported formats, do <code>mipgen --help</code>.</p>
-<p>In a production setting, you&#x27;d want to invoke these commands with a script or build system.</p>
+<p>For more information on mipgen's arguments and supported formats, do <code>mipgen --help</code>.</p>
+<p>In a production setting, you'd want to invoke these commands with a script or build system.</p>
 <h2>Bake environment map</h2>
-<p>Much like the <a href="tutorial_redball.html">previous tutorial</a> we need to use Filament&#x27;s <code>cmgen</code> tool to produce cubemap files.</p>
+<p>Much like the <a href="tutorial_redball.html">previous tutorial</a> we need to use Filament's <code>cmgen</code> tool to produce cubemap files.</p>
 <p>Download <a href="//github.com/google/filament/blob/main/third_party/environments/venetian_crossroads_2k.hdr">venetian_crossroads_2k.hdr</a>, then invoke the following commands in your terminal.</p>
-<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span>cmgen -x . --format<span style="color: #666666">=</span>ktx --size<span style="color: #666666">=64</span> --extract-blur<span style="color: #666666">=0</span>.1 venetian_crossroads_2k.hdr
-<span style="color: #008000">cd</span> venetian* ; mv venetian*_ibl.ktx venetian_crossroads_2k_skybox_tiny.ktx ; <span style="color: #008000">cd</span> -
+<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span>cmgen<span style="color: #BBB"> </span>-x<span style="color: #BBB"> </span>.<span style="color: #BBB"> </span>--format<span style="color: #666">=</span>ktx<span style="color: #BBB"> </span>--size<span style="color: #666">=64</span><span style="color: #BBB"> </span>--extract-blur<span style="color: #666">=0</span>.1<span style="color: #BBB"> </span>venetian_crossroads_2k.hdr
+<span style="color: #008000">cd</span><span style="color: #BBB"> </span>venetian*<span style="color: #BBB"> </span>;<span style="color: #BBB"> </span>mv<span style="color: #BBB"> </span>venetian*_ibl.ktx<span style="color: #BBB"> </span>venetian_crossroads_2k_skybox_tiny.ktx<span style="color: #BBB"> </span>;<span style="color: #BBB"> </span><span style="color: #008000">cd</span><span style="color: #BBB"> </span>-
 
-cmgen -x . --format<span style="color: #666666">=</span>ktx --size<span style="color: #666666">=256</span> --extract-blur<span style="color: #666666">=0</span>.1 venetian_crossroads_2k.hdr
-cmgen -x . --format<span style="color: #666666">=</span>ktx --size<span style="color: #666666">=256</span> --extract-blur<span style="color: #666666">=0</span>.1 venetian_crossroads_2k.hdr
-cmgen -x . --format<span style="color: #666666">=</span>ktx --size<span style="color: #666666">=256</span> --extract-blur<span style="color: #666666">=0</span>.1 venetian_crossroads_2k.hdr
+cmgen<span style="color: #BBB"> </span>-x<span style="color: #BBB"> </span>.<span style="color: #BBB"> </span>--format<span style="color: #666">=</span>ktx<span style="color: #BBB"> </span>--size<span style="color: #666">=256</span><span style="color: #BBB"> </span>--extract-blur<span style="color: #666">=0</span>.1<span style="color: #BBB"> </span>venetian_crossroads_2k.hdr
+cmgen<span style="color: #BBB"> </span>-x<span style="color: #BBB"> </span>.<span style="color: #BBB"> </span>--format<span style="color: #666">=</span>ktx<span style="color: #BBB"> </span>--size<span style="color: #666">=256</span><span style="color: #BBB"> </span>--extract-blur<span style="color: #666">=0</span>.1<span style="color: #BBB"> </span>venetian_crossroads_2k.hdr
+cmgen<span style="color: #BBB"> </span>-x<span style="color: #BBB"> </span>.<span style="color: #BBB"> </span>--format<span style="color: #666">=</span>ktx<span style="color: #BBB"> </span>--size<span style="color: #666">=256</span><span style="color: #BBB"> </span>--extract-blur<span style="color: #666">=0</span>.1<span style="color: #BBB"> </span>venetian_crossroads_2k.hdr
 </pre></div>
 
 <h2>Define textured material</h2>
 <p>You might recall the <code>filamat</code> file we generated in the previous tutorial for red plastic. For this
-demo, we&#x27;ll create a material that uses textures for several parameters.</p>
+demo, we'll create a material that uses textures for several parameters.</p>
 <p>Create the following text file and call it <code>textured.mat</code>. Note that our material definition now
 requires a <code>uv0</code> attribute.</p>
 <div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span>material {
@@ -90,7 +90,7 @@ fragment {
 </pre></div>
 
 <p>Next, invoke <code>matc</code> as follows.</p>
-<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span>matc -a opengl -p mobile -o textured.filamat textured.mat
+<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span>matc<span style="color: #BBB"> </span>-a<span style="color: #BBB"> </span>opengl<span style="color: #BBB"> </span>-p<span style="color: #BBB"> </span>mobile<span style="color: #BBB"> </span>-o<span style="color: #BBB"> </span>textured.filamat<span style="color: #BBB"> </span>textured.mat
 </pre></div>
 
 <p>You should now have a material archive in your working directory. For the suzanne asset, the normal
@@ -100,65 +100,65 @@ materials, consult the official document describing the <a href="https://google.
 <p>Create a text file called <code>suzanne.html</code> and copy over the HTML that we used in the <a href="tutorial_redball.html">previous
 tutorial</a>. Change the last script tag from <code>redball.js</code> to <code>suzanne.js</code>. Next, create <code>suzanne.js</code>
 with the following content.</p>
-<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #3D7B7B; font-style: italic">// TODO: declare asset URLs</span><span style="color: #bbbbbb"></span>
+<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #3D7B7B; font-style: italic">// TODO: declare asset URLs</span>
 
-Filament.init([<span style="color: #bbbbbb"> </span>filamat_url,<span style="color: #bbbbbb"> </span>filamesh_url,<span style="color: #bbbbbb"> </span>sky_small_url,<span style="color: #bbbbbb"> </span>ibl_url<span style="color: #bbbbbb"> </span>],<span style="color: #bbbbbb"> </span>()<span style="color: #bbbbbb"> </span>=&gt;<span style="color: #bbbbbb"> </span>{<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #008000">window</span>.app<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #AA22FF; font-weight: bold">new</span><span style="color: #bbbbbb"> </span>App(<span style="color: #008000">document</span>.getElementsByTagName(<span style="color: #BA2121">&#39;canvas&#39;</span>)[<span style="color: #666666">0</span>]);<span style="color: #bbbbbb"></span>
-});<span style="color: #bbbbbb"></span>
+Filament.init([<span style="color: #BBB"> </span>filamat_url,<span style="color: #BBB"> </span>filamesh_url,<span style="color: #BBB"> </span>sky_small_url,<span style="color: #BBB"> </span>ibl_url<span style="color: #BBB"> </span>],<span style="color: #BBB"> </span>()<span style="color: #BBB"> </span>=&gt;<span style="color: #BBB"> </span>{
+<span style="color: #BBB">    </span><span style="color: #008000">window</span>.app<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #A2F; font-weight: bold">new</span><span style="color: #BBB"> </span>App(<span style="color: #008000">document</span>.getElementsByTagName(<span style="color: #BA2121">&#39;canvas&#39;</span>)[<span style="color: #666">0</span>]);
+});
 
-<span style="color: #008000; font-weight: bold">class</span><span style="color: #bbbbbb"> </span>App<span style="color: #bbbbbb"> </span>{<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #008000; font-weight: bold">constructor</span>(canvas)<span style="color: #bbbbbb"> </span>{<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">        </span><span style="color: #008000; font-weight: bold">this</span>.canvas<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>canvas;<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">        </span><span style="color: #008000; font-weight: bold">this</span>.engine<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>Filament.Engine.create(canvas);<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">        </span><span style="color: #008000; font-weight: bold">this</span>.scene<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.createScene();<span style="color: #bbbbbb"></span>
+<span style="color: #008000; font-weight: bold">class</span><span style="color: #BBB"> </span>App<span style="color: #BBB"> </span>{
+<span style="color: #BBB">    </span><span style="color: #008000; font-weight: bold">constructor</span>(canvas)<span style="color: #BBB"> </span>{
+<span style="color: #BBB">        </span><span style="color: #008000; font-weight: bold">this</span>.canvas<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>canvas;
+<span style="color: #BBB">        </span><span style="color: #008000; font-weight: bold">this</span>.engine<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>Filament.Engine.create(canvas);
+<span style="color: #BBB">        </span><span style="color: #008000; font-weight: bold">this</span>.scene<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.createScene();
 
-<span style="color: #bbbbbb">        </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>material<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.createMaterial(filamat_url);<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">        </span><span style="color: #008000; font-weight: bold">this</span>.matinstance<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>material.createInstance();<span style="color: #bbbbbb"></span>
+<span style="color: #BBB">        </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>material<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.createMaterial(filamat_url);
+<span style="color: #BBB">        </span><span style="color: #008000; font-weight: bold">this</span>.matinstance<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>material.createInstance();
 
-<span style="color: #bbbbbb">        </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>filamesh<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.loadFilamesh(filamesh_url,<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.matinstance);<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">        </span><span style="color: #008000; font-weight: bold">this</span>.suzanne<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>filamesh.renderable;<span style="color: #bbbbbb"></span>
+<span style="color: #BBB">        </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>filamesh<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.loadFilamesh(filamesh_url,<span style="color: #BBB"> </span><span style="color: #008000; font-weight: bold">this</span>.matinstance);
+<span style="color: #BBB">        </span><span style="color: #008000; font-weight: bold">this</span>.suzanne<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>filamesh.renderable;
 
-<span style="color: #bbbbbb">        </span><span style="color: #3D7B7B; font-style: italic">// TODO: create sky box and IBL</span><span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">        </span><span style="color: #3D7B7B; font-style: italic">// TODO: initialize gltumble</span><span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">        </span><span style="color: #3D7B7B; font-style: italic">// TODO: fetch larger assets</span><span style="color: #bbbbbb"></span>
+<span style="color: #BBB">        </span><span style="color: #3D7B7B; font-style: italic">// TODO: create sky box and IBL</span>
+<span style="color: #BBB">        </span><span style="color: #3D7B7B; font-style: italic">// TODO: initialize gltumble</span>
+<span style="color: #BBB">        </span><span style="color: #3D7B7B; font-style: italic">// TODO: fetch larger assets</span>
 
-<span style="color: #bbbbbb">        </span><span style="color: #008000; font-weight: bold">this</span>.swapChain<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.createSwapChain();<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">        </span><span style="color: #008000; font-weight: bold">this</span>.renderer<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.createRenderer();<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">        </span><span style="color: #008000; font-weight: bold">this</span>.camera<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.createCamera(Filament.EntityManager.get().create());<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">        </span><span style="color: #008000; font-weight: bold">this</span>.view<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.createView();<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">        </span><span style="color: #008000; font-weight: bold">this</span>.view.setCamera(<span style="color: #008000; font-weight: bold">this</span>.camera);<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">        </span><span style="color: #008000; font-weight: bold">this</span>.view.setScene(<span style="color: #008000; font-weight: bold">this</span>.scene);<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">        </span><span style="color: #008000; font-weight: bold">this</span>.render<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.render.bind(<span style="color: #008000; font-weight: bold">this</span>);<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">        </span><span style="color: #008000; font-weight: bold">this</span>.resize<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.resize.bind(<span style="color: #008000; font-weight: bold">this</span>);<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">        </span><span style="color: #008000">window</span>.addEventListener(<span style="color: #BA2121">&#39;resize&#39;</span>,<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.resize);<span style="color: #bbbbbb"></span>
+<span style="color: #BBB">        </span><span style="color: #008000; font-weight: bold">this</span>.swapChain<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.createSwapChain();
+<span style="color: #BBB">        </span><span style="color: #008000; font-weight: bold">this</span>.renderer<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.createRenderer();
+<span style="color: #BBB">        </span><span style="color: #008000; font-weight: bold">this</span>.camera<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.createCamera(Filament.EntityManager.get().create());
+<span style="color: #BBB">        </span><span style="color: #008000; font-weight: bold">this</span>.view<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.createView();
+<span style="color: #BBB">        </span><span style="color: #008000; font-weight: bold">this</span>.view.setCamera(<span style="color: #008000; font-weight: bold">this</span>.camera);
+<span style="color: #BBB">        </span><span style="color: #008000; font-weight: bold">this</span>.view.setScene(<span style="color: #008000; font-weight: bold">this</span>.scene);
+<span style="color: #BBB">        </span><span style="color: #008000; font-weight: bold">this</span>.render<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #008000; font-weight: bold">this</span>.render.bind(<span style="color: #008000; font-weight: bold">this</span>);
+<span style="color: #BBB">        </span><span style="color: #008000; font-weight: bold">this</span>.resize<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #008000; font-weight: bold">this</span>.resize.bind(<span style="color: #008000; font-weight: bold">this</span>);
+<span style="color: #BBB">        </span><span style="color: #008000">window</span>.addEventListener(<span style="color: #BA2121">&#39;resize&#39;</span>,<span style="color: #BBB"> </span><span style="color: #008000; font-weight: bold">this</span>.resize);
 
-<span style="color: #bbbbbb">        </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>eye<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>[<span style="color: #666666">0</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">0</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">4</span>],<span style="color: #bbbbbb"> </span>center<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>[<span style="color: #666666">0</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">0</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">0</span>],<span style="color: #bbbbbb"> </span>up<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>[<span style="color: #666666">0</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">1</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">0</span>];<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">        </span><span style="color: #008000; font-weight: bold">this</span>.camera.lookAt(eye,<span style="color: #bbbbbb"> </span>center,<span style="color: #bbbbbb"> </span>up);<span style="color: #bbbbbb"></span>
+<span style="color: #BBB">        </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>eye<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>[<span style="color: #666">0</span>,<span style="color: #BBB"> </span><span style="color: #666">0</span>,<span style="color: #BBB"> </span><span style="color: #666">4</span>],<span style="color: #BBB"> </span>center<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>[<span style="color: #666">0</span>,<span style="color: #BBB"> </span><span style="color: #666">0</span>,<span style="color: #BBB"> </span><span style="color: #666">0</span>],<span style="color: #BBB"> </span>up<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>[<span style="color: #666">0</span>,<span style="color: #BBB"> </span><span style="color: #666">1</span>,<span style="color: #BBB"> </span><span style="color: #666">0</span>];
+<span style="color: #BBB">        </span><span style="color: #008000; font-weight: bold">this</span>.camera.lookAt(eye,<span style="color: #BBB"> </span>center,<span style="color: #BBB"> </span>up);
 
-<span style="color: #bbbbbb">        </span><span style="color: #008000; font-weight: bold">this</span>.resize();<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">        </span><span style="color: #008000">window</span>.requestAnimationFrame(<span style="color: #008000; font-weight: bold">this</span>.render);<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span>}<span style="color: #bbbbbb"></span>
+<span style="color: #BBB">        </span><span style="color: #008000; font-weight: bold">this</span>.resize();
+<span style="color: #BBB">        </span><span style="color: #008000">window</span>.requestAnimationFrame(<span style="color: #008000; font-weight: bold">this</span>.render);
+<span style="color: #BBB">    </span>}
 
-<span style="color: #bbbbbb">    </span>render()<span style="color: #bbbbbb"> </span>{<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">        </span><span style="color: #3D7B7B; font-style: italic">// TODO: apply gltumble matrix</span><span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">        </span><span style="color: #008000; font-weight: bold">this</span>.renderer.render(<span style="color: #008000; font-weight: bold">this</span>.swapChain,<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.view);<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">        </span><span style="color: #008000">window</span>.requestAnimationFrame(<span style="color: #008000; font-weight: bold">this</span>.render);<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span>}<span style="color: #bbbbbb"></span>
+<span style="color: #BBB">    </span>render()<span style="color: #BBB"> </span>{
+<span style="color: #BBB">        </span><span style="color: #3D7B7B; font-style: italic">// TODO: apply gltumble matrix</span>
+<span style="color: #BBB">        </span><span style="color: #008000; font-weight: bold">this</span>.renderer.render(<span style="color: #008000; font-weight: bold">this</span>.swapChain,<span style="color: #BBB"> </span><span style="color: #008000; font-weight: bold">this</span>.view);
+<span style="color: #BBB">        </span><span style="color: #008000">window</span>.requestAnimationFrame(<span style="color: #008000; font-weight: bold">this</span>.render);
+<span style="color: #BBB">    </span>}
 
-<span style="color: #bbbbbb">    </span>resize()<span style="color: #bbbbbb"> </span>{<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">        </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>dpr<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000">window</span>.devicePixelRatio;<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">        </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>width<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.canvas.width<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000">window</span>.innerWidth<span style="color: #bbbbbb"> </span><span style="color: #666666">*</span><span style="color: #bbbbbb"> </span>dpr;<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">        </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>height<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.canvas.height<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000">window</span>.innerHeight<span style="color: #bbbbbb"> </span><span style="color: #666666">*</span><span style="color: #bbbbbb"> </span>dpr;<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">        </span><span style="color: #008000; font-weight: bold">this</span>.view.setViewport([<span style="color: #666666">0</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">0</span>,<span style="color: #bbbbbb"> </span>width,<span style="color: #bbbbbb"> </span>height]);<span style="color: #bbbbbb"></span>
+<span style="color: #BBB">    </span>resize()<span style="color: #BBB"> </span>{
+<span style="color: #BBB">        </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>dpr<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #008000">window</span>.devicePixelRatio;
+<span style="color: #BBB">        </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>width<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #008000; font-weight: bold">this</span>.canvas.width<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #008000">window</span>.innerWidth<span style="color: #BBB"> </span><span style="color: #666">*</span><span style="color: #BBB"> </span>dpr;
+<span style="color: #BBB">        </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>height<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #008000; font-weight: bold">this</span>.canvas.height<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #008000">window</span>.innerHeight<span style="color: #BBB"> </span><span style="color: #666">*</span><span style="color: #BBB"> </span>dpr;
+<span style="color: #BBB">        </span><span style="color: #008000; font-weight: bold">this</span>.view.setViewport([<span style="color: #666">0</span>,<span style="color: #BBB"> </span><span style="color: #666">0</span>,<span style="color: #BBB"> </span>width,<span style="color: #BBB"> </span>height]);
 
-<span style="color: #bbbbbb">        </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>aspect<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>width<span style="color: #bbbbbb"> </span><span style="color: #666666">/</span><span style="color: #bbbbbb"> </span>height;<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">        </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>Fov<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>Filament.Camera$Fov,<span style="color: #bbbbbb"> </span>fov<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>aspect<span style="color: #bbbbbb"> </span><span style="color: #666666">&lt;</span><span style="color: #bbbbbb"> </span><span style="color: #666666">1</span><span style="color: #bbbbbb"> </span><span style="color: #666666">?</span><span style="color: #bbbbbb"> </span>Fov.HORIZONTAL<span style="color: #bbbbbb"> </span><span style="color: #666666">:</span><span style="color: #bbbbbb"> </span>Fov.VERTICAL;<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">        </span><span style="color: #008000; font-weight: bold">this</span>.camera.setProjectionFov(<span style="color: #666666">45</span>,<span style="color: #bbbbbb"> </span>aspect,<span style="color: #bbbbbb"> </span><span style="color: #666666">1.0</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">10.0</span>,<span style="color: #bbbbbb"> </span>fov);<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span>}<span style="color: #bbbbbb"></span>
-}<span style="color: #bbbbbb"></span>
+<span style="color: #BBB">        </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>aspect<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>width<span style="color: #BBB"> </span><span style="color: #666">/</span><span style="color: #BBB"> </span>height;
+<span style="color: #BBB">        </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>Fov<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>Filament.Camera$Fov,<span style="color: #BBB"> </span>fov<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>aspect<span style="color: #BBB"> </span><span style="color: #666">&lt;</span><span style="color: #BBB"> </span><span style="color: #666">1</span><span style="color: #BBB"> </span><span style="color: #666">?</span><span style="color: #BBB"> </span>Fov.HORIZONTAL<span style="color: #BBB"> </span><span style="color: #666">:</span><span style="color: #BBB"> </span>Fov.VERTICAL;
+<span style="color: #BBB">        </span><span style="color: #008000; font-weight: bold">this</span>.camera.setProjectionFov(<span style="color: #666">45</span>,<span style="color: #BBB"> </span>aspect,<span style="color: #BBB"> </span><span style="color: #666">1.0</span>,<span style="color: #BBB"> </span><span style="color: #666">10.0</span>,<span style="color: #BBB"> </span>fov);
+<span style="color: #BBB">    </span>}
+}
 </pre></div>
 
-<p>Our app will only require a subset of assets to be present for <code>App</code> construction. We&#x27;ll download
+<p>Our app will only require a subset of assets to be present for <code>App</code> construction. We'll download
 the other assets after construction. By using a progressive loading strategy, we can reduce the
 perceived load time.</p>
 <p>Next we need to supply the URLs for various assets. This is actually a bit tricky, because different
@@ -171,85 +171,85 @@ string -- which might be empty.</p>
 <p>In our case, we know that our web server will have <code>astc</code> and <code>s3tc</code> variants for albedo, and <code>etc</code>
 variants for the other textures. The uncompressed variants (empty string) are always available as a
 last resort. Go ahead and replace the <strong>declare asset URLs</strong> comment with the following snippet.</p>
-<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>albedo_suffix<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>Filament.getSupportedFormatSuffix(<span style="color: #BA2121">&#39;astc s3tc_srgb&#39;</span>);<span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>texture_suffix<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>Filament.getSupportedFormatSuffix(<span style="color: #BA2121">&#39;etc&#39;</span>);<span style="color: #bbbbbb"></span>
+<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>albedo_suffix<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>Filament.getSupportedFormatSuffix(<span style="color: #BA2121">&#39;astc s3tc_srgb&#39;</span>);
+<span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>texture_suffix<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>Filament.getSupportedFormatSuffix(<span style="color: #BA2121">&#39;etc&#39;</span>);
 
-<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>environ<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #BA2121">&#39;venetian_crossroads_2k&#39;</span><span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>ibl_url<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #BA2121">`</span><span style="color: #A45A77; font-weight: bold">${</span>environ<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">/</span><span style="color: #A45A77; font-weight: bold">${</span>environ<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">_ibl.ktx`</span>;<span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>sky_small_url<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #BA2121">`</span><span style="color: #A45A77; font-weight: bold">${</span>environ<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">/</span><span style="color: #A45A77; font-weight: bold">${</span>environ<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">_skybox_tiny.ktx`</span>;<span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>sky_large_url<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #BA2121">`</span><span style="color: #A45A77; font-weight: bold">${</span>environ<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">/</span><span style="color: #A45A77; font-weight: bold">${</span>environ<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">_skybox.ktx`</span>;<span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>albedo_url<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #BA2121">`albedo</span><span style="color: #A45A77; font-weight: bold">${</span>albedo_suffix<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">.ktx`</span>;<span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>ao_url<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #BA2121">`ao</span><span style="color: #A45A77; font-weight: bold">${</span>texture_suffix<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">.ktx`</span>;<span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>metallic_url<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #BA2121">`metallic</span><span style="color: #A45A77; font-weight: bold">${</span>texture_suffix<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">.ktx`</span>;<span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>normal_url<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #BA2121">`normal</span><span style="color: #A45A77; font-weight: bold">${</span>texture_suffix<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">.ktx`</span>;<span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>roughness_url<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #BA2121">`roughness</span><span style="color: #A45A77; font-weight: bold">${</span>texture_suffix<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">.ktx`</span>;<span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>filamat_url<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #BA2121">&#39;textured.filamat&#39;</span>;<span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>filamesh_url<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #BA2121">&#39;suzanne.filamesh&#39;</span>;<span style="color: #bbbbbb"></span>
+<span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>environ<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #BA2121">&#39;venetian_crossroads_2k&#39;</span>
+<span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>ibl_url<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #BA2121">`</span><span style="color: #A45A77; font-weight: bold">${</span>environ<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">/</span><span style="color: #A45A77; font-weight: bold">${</span>environ<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">_ibl.ktx`</span>;
+<span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>sky_small_url<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #BA2121">`</span><span style="color: #A45A77; font-weight: bold">${</span>environ<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">/</span><span style="color: #A45A77; font-weight: bold">${</span>environ<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">_skybox_tiny.ktx`</span>;
+<span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>sky_large_url<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #BA2121">`</span><span style="color: #A45A77; font-weight: bold">${</span>environ<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">/</span><span style="color: #A45A77; font-weight: bold">${</span>environ<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">_skybox.ktx`</span>;
+<span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>albedo_url<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #BA2121">`albedo</span><span style="color: #A45A77; font-weight: bold">${</span>albedo_suffix<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">.ktx`</span>;
+<span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>ao_url<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #BA2121">`ao</span><span style="color: #A45A77; font-weight: bold">${</span>texture_suffix<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">.ktx`</span>;
+<span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>metallic_url<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #BA2121">`metallic</span><span style="color: #A45A77; font-weight: bold">${</span>texture_suffix<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">.ktx`</span>;
+<span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>normal_url<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #BA2121">`normal</span><span style="color: #A45A77; font-weight: bold">${</span>texture_suffix<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">.ktx`</span>;
+<span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>roughness_url<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #BA2121">`roughness</span><span style="color: #A45A77; font-weight: bold">${</span>texture_suffix<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">.ktx`</span>;
+<span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>filamat_url<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #BA2121">&#39;textured.filamat&#39;</span>;
+<span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>filamesh_url<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #BA2121">&#39;suzanne.filamesh&#39;</span>;
 </pre></div>
 
 <h2>Create skybox and IBL</h2>
-<p>Next, let&#x27;s create the low-resolution skybox and IBL in the <code>App</code> constructor.</p>
-<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #008000; font-weight: bold">this</span>.skybox<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.createSkyFromKtx1(sky_small_url);<span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">this</span>.scene.setSkybox(<span style="color: #008000; font-weight: bold">this</span>.skybox);<span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">this</span>.indirectLight<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.createIblFromKtx1(ibl_url);<span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">this</span>.indirectLight.setIntensity(<span style="color: #666666">100000</span>);<span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">this</span>.scene.setIndirectLight(<span style="color: #008000; font-weight: bold">this</span>.indirectLight);<span style="color: #bbbbbb"></span>
+<p>Next, let's create the low-resolution skybox and IBL in the <code>App</code> constructor.</p>
+<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #008000; font-weight: bold">this</span>.skybox<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.createSkyFromKtx1(sky_small_url);
+<span style="color: #008000; font-weight: bold">this</span>.scene.setSkybox(<span style="color: #008000; font-weight: bold">this</span>.skybox);
+<span style="color: #008000; font-weight: bold">this</span>.indirectLight<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.createIblFromKtx1(ibl_url);
+<span style="color: #008000; font-weight: bold">this</span>.indirectLight.setIntensity(<span style="color: #666">100000</span>);
+<span style="color: #008000; font-weight: bold">this</span>.scene.setIndirectLight(<span style="color: #008000; font-weight: bold">this</span>.indirectLight);
 </pre></div>
 
 <p>This allows users to see a reasonable background fairly quickly, before larger assets have finished
 loading in.</p>
 <h2>Fetch assets asychronously</h2>
-<p>Next we&#x27;ll invoke the <code>Filament.fetch</code> function from within the app constructor. This function is
+<p>Next we'll invoke the <code>Filament.fetch</code> function from within the app constructor. This function is
 very similar to <code>Filament.init</code>. It takes a list of asset URLs and a callback function that triggers
 when the assets have finished downloading.</p>
-<p>In our callback, we&#x27;ll make several <code>setTextureParameter</code> calls on the material instance, then we&#x27;ll
+<p>In our callback, we'll make several <code>setTextureParameter</code> calls on the material instance, then we'll
 recreate the skybox using a higher-resolution texture. As a last step we unhide the renderable that
 was created in the app constructor.</p>
-<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span>Filament.fetch([sky_large_url,<span style="color: #bbbbbb"> </span>albedo_url,<span style="color: #bbbbbb"> </span>roughness_url,<span style="color: #bbbbbb"> </span>metallic_url,<span style="color: #bbbbbb"> </span>normal_url,<span style="color: #bbbbbb"> </span>ao_url],<span style="color: #bbbbbb"> </span>()<span style="color: #bbbbbb"> </span>=&gt;<span style="color: #bbbbbb"> </span>{<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>albedo<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.createTextureFromKtx2(albedo_url,<span style="color: #bbbbbb"> </span>{srgb<span style="color: #666666">:</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">true</span>});<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>roughness<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.createTextureFromKtx2(roughness_url);<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>metallic<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.createTextureFromKtx2(metallic_url);<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>normal<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.createTextureFromKtx2(normal_url);<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>ao<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.createTextureFromKtx2(ao_url);<span style="color: #bbbbbb"></span>
+<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span>Filament.fetch([sky_large_url,<span style="color: #BBB"> </span>albedo_url,<span style="color: #BBB"> </span>roughness_url,<span style="color: #BBB"> </span>metallic_url,<span style="color: #BBB"> </span>normal_url,<span style="color: #BBB"> </span>ao_url],<span style="color: #BBB"> </span>()<span style="color: #BBB"> </span>=&gt;<span style="color: #BBB"> </span>{
+<span style="color: #BBB">    </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>albedo<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.createTextureFromKtx2(albedo_url,<span style="color: #BBB"> </span>{srgb<span style="color: #666">:</span><span style="color: #BBB"> </span><span style="color: #008000; font-weight: bold">true</span>});
+<span style="color: #BBB">    </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>roughness<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.createTextureFromKtx2(roughness_url);
+<span style="color: #BBB">    </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>metallic<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.createTextureFromKtx2(metallic_url);
+<span style="color: #BBB">    </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>normal<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.createTextureFromKtx2(normal_url);
+<span style="color: #BBB">    </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>ao<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.createTextureFromKtx2(ao_url);
 
-<span style="color: #bbbbbb">    </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>sampler<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #AA22FF; font-weight: bold">new</span><span style="color: #bbbbbb"> </span>Filament.TextureSampler(<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">        </span>Filament.MinFilter.LINEAR_MIPMAP_LINEAR,<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">        </span>Filament.MagFilter.LINEAR,<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">        </span>Filament.WrapMode.CLAMP_TO_EDGE);<span style="color: #bbbbbb"></span>
+<span style="color: #BBB">    </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>sampler<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #A2F; font-weight: bold">new</span><span style="color: #BBB"> </span>Filament.TextureSampler(
+<span style="color: #BBB">        </span>Filament.MinFilter.LINEAR_MIPMAP_LINEAR,
+<span style="color: #BBB">        </span>Filament.MagFilter.LINEAR,
+<span style="color: #BBB">        </span>Filament.WrapMode.CLAMP_TO_EDGE);
 
-<span style="color: #bbbbbb">    </span><span style="color: #008000; font-weight: bold">this</span>.matinstance.setTextureParameter(<span style="color: #BA2121">&#39;albedo&#39;</span>,<span style="color: #bbbbbb"> </span>albedo,<span style="color: #bbbbbb"> </span>sampler);<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #008000; font-weight: bold">this</span>.matinstance.setTextureParameter(<span style="color: #BA2121">&#39;roughness&#39;</span>,<span style="color: #bbbbbb"> </span>roughness,<span style="color: #bbbbbb"> </span>sampler);<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #008000; font-weight: bold">this</span>.matinstance.setTextureParameter(<span style="color: #BA2121">&#39;metallic&#39;</span>,<span style="color: #bbbbbb"> </span>metallic,<span style="color: #bbbbbb"> </span>sampler);<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #008000; font-weight: bold">this</span>.matinstance.setTextureParameter(<span style="color: #BA2121">&#39;normal&#39;</span>,<span style="color: #bbbbbb"> </span>normal,<span style="color: #bbbbbb"> </span>sampler);<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #008000; font-weight: bold">this</span>.matinstance.setTextureParameter(<span style="color: #BA2121">&#39;ao&#39;</span>,<span style="color: #bbbbbb"> </span>ao,<span style="color: #bbbbbb"> </span>sampler);<span style="color: #bbbbbb"></span>
+<span style="color: #BBB">    </span><span style="color: #008000; font-weight: bold">this</span>.matinstance.setTextureParameter(<span style="color: #BA2121">&#39;albedo&#39;</span>,<span style="color: #BBB"> </span>albedo,<span style="color: #BBB"> </span>sampler);
+<span style="color: #BBB">    </span><span style="color: #008000; font-weight: bold">this</span>.matinstance.setTextureParameter(<span style="color: #BA2121">&#39;roughness&#39;</span>,<span style="color: #BBB"> </span>roughness,<span style="color: #BBB"> </span>sampler);
+<span style="color: #BBB">    </span><span style="color: #008000; font-weight: bold">this</span>.matinstance.setTextureParameter(<span style="color: #BA2121">&#39;metallic&#39;</span>,<span style="color: #BBB"> </span>metallic,<span style="color: #BBB"> </span>sampler);
+<span style="color: #BBB">    </span><span style="color: #008000; font-weight: bold">this</span>.matinstance.setTextureParameter(<span style="color: #BA2121">&#39;normal&#39;</span>,<span style="color: #BBB"> </span>normal,<span style="color: #BBB"> </span>sampler);
+<span style="color: #BBB">    </span><span style="color: #008000; font-weight: bold">this</span>.matinstance.setTextureParameter(<span style="color: #BA2121">&#39;ao&#39;</span>,<span style="color: #BBB"> </span>ao,<span style="color: #BBB"> </span>sampler);
 
-<span style="color: #bbbbbb">    </span><span style="color: #3D7B7B; font-style: italic">// Replace low-res skybox with high-res skybox.</span><span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #008000; font-weight: bold">this</span>.engine.destroySkybox(<span style="color: #008000; font-weight: bold">this</span>.skybox);<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #008000; font-weight: bold">this</span>.skybox<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.createSkyFromKtx1(sky_large_url);<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #008000; font-weight: bold">this</span>.scene.setSkybox(<span style="color: #008000; font-weight: bold">this</span>.skybox);<span style="color: #bbbbbb"></span>
+<span style="color: #BBB">    </span><span style="color: #3D7B7B; font-style: italic">// Replace low-res skybox with high-res skybox.</span>
+<span style="color: #BBB">    </span><span style="color: #008000; font-weight: bold">this</span>.engine.destroySkybox(<span style="color: #008000; font-weight: bold">this</span>.skybox);
+<span style="color: #BBB">    </span><span style="color: #008000; font-weight: bold">this</span>.skybox<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.createSkyFromKtx1(sky_large_url);
+<span style="color: #BBB">    </span><span style="color: #008000; font-weight: bold">this</span>.scene.setSkybox(<span style="color: #008000; font-weight: bold">this</span>.skybox);
 
-<span style="color: #bbbbbb">    </span><span style="color: #008000; font-weight: bold">this</span>.scene.addEntity(<span style="color: #008000; font-weight: bold">this</span>.suzanne);<span style="color: #bbbbbb"></span>
-});<span style="color: #bbbbbb"></span>
+<span style="color: #BBB">    </span><span style="color: #008000; font-weight: bold">this</span>.scene.addEntity(<span style="color: #008000; font-weight: bold">this</span>.suzanne);
+});
 </pre></div>
 
 <h2>Introduce trackball rotation</h2>
 <p>Add the following script tag to your HTML file. This imports a small third-party library that
 listens for drag events and computes a rotation matrix.</p>
-<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span>&lt;<span style="color: #008000; font-weight: bold">script</span> <span style="color: #687822">src</span><span style="color: #666666">=</span><span style="color: #BA2121">&quot;//unpkg.com/gltumble&quot;</span>&gt;&lt;/<span style="color: #008000; font-weight: bold">script</span>&gt;
+<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span>&lt;<span style="color: #008000; font-weight: bold">script</span> <span style="color: #687822">src</span><span style="color: #666">=</span><span style="color: #BA2121">&quot;//unpkg.com/gltumble&quot;</span>&gt;&lt;/<span style="color: #008000; font-weight: bold">script</span>&gt;
 </pre></div>
 
 <p>Next, replace the <strong>initialize gltumble</strong> and <strong>apply gltumble matrix</strong> comments with the following
 two code snippets.</p>
-<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #008000; font-weight: bold">this</span>.trackball<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #AA22FF; font-weight: bold">new</span><span style="color: #bbbbbb"> </span>Trackball(canvas,<span style="color: #bbbbbb"> </span>{startSpin<span style="color: #666666">:</span><span style="color: #bbbbbb"> </span><span style="color: #666666">0.035</span>});<span style="color: #bbbbbb"></span>
+<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #008000; font-weight: bold">this</span>.trackball<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #A2F; font-weight: bold">new</span><span style="color: #BBB"> </span>Trackball(canvas,<span style="color: #BBB"> </span>{startSpin<span style="color: #666">:</span><span style="color: #BBB"> </span><span style="color: #666">0.035</span>});
 </pre></div>
 
-<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>tcm<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.getTransformManager();<span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>inst<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>tcm.getInstance(<span style="color: #008000; font-weight: bold">this</span>.suzanne);<span style="color: #bbbbbb"></span>
-tcm.setTransform(inst,<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.trackball.getMatrix());<span style="color: #bbbbbb"></span>
-inst.<span style="color: #AA22FF; font-weight: bold">delete</span>();<span style="color: #bbbbbb"></span>
+<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>tcm<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.getTransformManager();
+<span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>inst<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>tcm.getInstance(<span style="color: #008000; font-weight: bold">this</span>.suzanne);
+tcm.setTransform(inst,<span style="color: #BBB"> </span><span style="color: #008000; font-weight: bold">this</span>.trackball.getMatrix());
+inst.<span style="color: #A2F; font-weight: bold">delete</span>();
 </pre></div>
 
-<p>That&#x27;s it, we now have a fast-loading interactive demo. The complete JavaScript file is available
+<p>That's it, we now have a fast-loading interactive demo. The complete JavaScript file is available
 <a href="tutorial_suzanne.js">here</a>.</p>
 
 </body>

docs/webgl/tutorial_triangle.html

@@ -8,30 +8,30 @@
 <div class="demo_frame"><iframe src="demo_triangle.html"></iframe><a href="demo_triangle.html">&#x1F517;</a></div>
 <h2>Literate programming</h2>
 <p>The markdown source for this tutorial is not only used to generate this
-web page, it&#x27;s also used to generate the JavaScript for the above demo.
+web page, it's also used to generate the JavaScript for the above demo.
 We use a small Python script for weaving (generating HTML) and tangling
-(generating JS). In the code samples, you&#x27;ll often see
+(generating JS). In the code samples, you'll often see
 <code>// TODO: &lt;some task&gt;</code>. These are special markers that get replaced by
 subsequent code blocks.</p>
 <h2>Start your project</h2>
 <p>First, create a text file called <code>triangle.html</code> and fill it with the following HTML. This creates
 a mobile-friendly page with a full-screen canvas.</p>
 <div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #9C6500">&lt;!DOCTYPE html&gt;</span>
-&lt;<span style="color: #008000; font-weight: bold">html</span> <span style="color: #687822">lang</span><span style="color: #666666">=</span><span style="color: #BA2121">&quot;en&quot;</span>&gt;
+&lt;<span style="color: #008000; font-weight: bold">html</span> <span style="color: #687822">lang</span><span style="color: #666">=</span><span style="color: #BA2121">&quot;en&quot;</span>&gt;
 &lt;<span style="color: #008000; font-weight: bold">head</span>&gt;
     &lt;<span style="color: #008000; font-weight: bold">title</span>&gt;Filament Tutorial&lt;/<span style="color: #008000; font-weight: bold">title</span>&gt;
-    &lt;<span style="color: #008000; font-weight: bold">meta</span> <span style="color: #687822">charset</span><span style="color: #666666">=</span><span style="color: #BA2121">&quot;utf-8&quot;</span>&gt;
-    &lt;<span style="color: #008000; font-weight: bold">meta</span> <span style="color: #687822">name</span><span style="color: #666666">=</span><span style="color: #BA2121">&quot;viewport&quot;</span> <span style="color: #687822">content</span><span style="color: #666666">=</span><span style="color: #BA2121">&quot;width=device-width,user-scalable=no,initial-scale=1&quot;</span>&gt;
-    &lt;<span style="color: #008000; font-weight: bold">style</span>&gt;<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">        </span><span style="color: #008000; font-weight: bold">body</span><span style="color: #bbbbbb"> </span>{<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">margin</span>:<span style="color: #bbbbbb"> </span><span style="color: #666666">0</span>;<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">overflow</span>:<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">hidden</span>;<span style="color: #bbbbbb"> </span>}<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">        </span><span style="color: #008000; font-weight: bold">canvas</span><span style="color: #bbbbbb"> </span>{<span style="color: #bbbbbb"> </span>touch-action:<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">none</span>;<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">width</span>:<span style="color: #bbbbbb"> </span><span style="color: #666666">100</span><span style="color: #B00040">%</span>;<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">height</span>:<span style="color: #bbbbbb"> </span><span style="color: #666666">100</span><span style="color: #B00040">%</span>;<span style="color: #bbbbbb"> </span>}<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span>&lt;/<span style="color: #008000; font-weight: bold">style</span>&gt;
+    &lt;<span style="color: #008000; font-weight: bold">meta</span> <span style="color: #687822">charset</span><span style="color: #666">=</span><span style="color: #BA2121">&quot;utf-8&quot;</span>&gt;
+    &lt;<span style="color: #008000; font-weight: bold">meta</span> <span style="color: #687822">name</span><span style="color: #666">=</span><span style="color: #BA2121">&quot;viewport&quot;</span> <span style="color: #687822">content</span><span style="color: #666">=</span><span style="color: #BA2121">&quot;width=device-width,user-scalable=no,initial-scale=1&quot;</span>&gt;
+    &lt;<span style="color: #008000; font-weight: bold">style</span>&gt;
+<span style="color: #BBB">        </span><span style="color: #008000; font-weight: bold">body</span><span style="color: #BBB"> </span>{<span style="color: #BBB"> </span><span style="color: #008000; font-weight: bold">margin</span>:<span style="color: #BBB"> </span><span style="color: #666">0</span>;<span style="color: #BBB"> </span><span style="color: #008000; font-weight: bold">overflow</span>:<span style="color: #BBB"> </span><span style="color: #008000; font-weight: bold">hidden</span>;<span style="color: #BBB"> </span>}
+<span style="color: #BBB">        </span><span style="color: #008000; font-weight: bold">canvas</span><span style="color: #BBB"> </span>{<span style="color: #BBB"> </span>touch-action:<span style="color: #BBB"> </span><span style="color: #008000; font-weight: bold">none</span>;<span style="color: #BBB"> </span><span style="color: #008000; font-weight: bold">width</span>:<span style="color: #BBB"> </span><span style="color: #666">100</span><span style="color: #B00040">%</span>;<span style="color: #BBB"> </span><span style="color: #008000; font-weight: bold">height</span>:<span style="color: #BBB"> </span><span style="color: #666">100</span><span style="color: #B00040">%</span>;<span style="color: #BBB"> </span>}
+<span style="color: #BBB">    </span>&lt;/<span style="color: #008000; font-weight: bold">style</span>&gt;
 &lt;/<span style="color: #008000; font-weight: bold">head</span>&gt;
 &lt;<span style="color: #008000; font-weight: bold">body</span>&gt;
     &lt;<span style="color: #008000; font-weight: bold">canvas</span>&gt;&lt;/<span style="color: #008000; font-weight: bold">canvas</span>&gt;
-    &lt;<span style="color: #008000; font-weight: bold">script</span> <span style="color: #687822">src</span><span style="color: #666666">=</span><span style="color: #BA2121">&quot;filament.js&quot;</span>&gt;&lt;/<span style="color: #008000; font-weight: bold">script</span>&gt;
-    &lt;<span style="color: #008000; font-weight: bold">script</span> <span style="color: #687822">src</span><span style="color: #666666">=</span><span style="color: #BA2121">&quot;//unpkg.com/gl-matrix@2.8.1&quot;</span>&gt;&lt;/<span style="color: #008000; font-weight: bold">script</span>&gt;
-    &lt;<span style="color: #008000; font-weight: bold">script</span> <span style="color: #687822">src</span><span style="color: #666666">=</span><span style="color: #BA2121">&quot;triangle.js&quot;</span>&gt;&lt;/<span style="color: #008000; font-weight: bold">script</span>&gt;
+    &lt;<span style="color: #008000; font-weight: bold">script</span> <span style="color: #687822">src</span><span style="color: #666">=</span><span style="color: #BA2121">&quot;filament.js&quot;</span>&gt;&lt;/<span style="color: #008000; font-weight: bold">script</span>&gt;
+    &lt;<span style="color: #008000; font-weight: bold">script</span> <span style="color: #687822">src</span><span style="color: #666">=</span><span style="color: #BA2121">&quot;//unpkg.com/gl-matrix@2.8.1&quot;</span>&gt;&lt;/<span style="color: #008000; font-weight: bold">script</span>&gt;
+    &lt;<span style="color: #008000; font-weight: bold">script</span> <span style="color: #687822">src</span><span style="color: #666">=</span><span style="color: #BA2121">&quot;triangle.js&quot;</span>&gt;&lt;/<span style="color: #008000; font-weight: bold">script</span>&gt;
 &lt;/<span style="color: #008000; font-weight: bold">body</span>&gt;
 &lt;/<span style="color: #008000; font-weight: bold">html</span>&gt;
 </pre></div>
@@ -48,63 +48,63 @@ a mobile-friendly page with a full-screen canvas.</p>
 <li><code>triangle.js</code> will contain your application code.</li>
 </ul>
 <p>Go ahead and create <code>triangle.js</code> with the following content.</p>
-<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #008000; font-weight: bold">class</span><span style="color: #bbbbbb"> </span>App<span style="color: #bbbbbb"> </span>{<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span><span style="color: #008000; font-weight: bold">constructor</span>()<span style="color: #bbbbbb"> </span>{<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #3D7B7B; font-style: italic">// TODO: create entities</span><span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #008000; font-weight: bold">this</span>.render<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.render.bind(<span style="color: #008000; font-weight: bold">this</span>);<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #008000; font-weight: bold">this</span>.resize<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.resize.bind(<span style="color: #008000; font-weight: bold">this</span>);<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #008000">window</span>.addEventListener(<span style="color: #BA2121">&#39;resize&#39;</span>,<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.resize);<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #008000">window</span>.requestAnimationFrame(<span style="color: #008000; font-weight: bold">this</span>.render);<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span>}<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span>render()<span style="color: #bbbbbb"> </span>{<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #3D7B7B; font-style: italic">// TODO: render scene</span><span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #008000">window</span>.requestAnimationFrame(<span style="color: #008000; font-weight: bold">this</span>.render);<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span>}<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span>resize()<span style="color: #bbbbbb"> </span>{<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #3D7B7B; font-style: italic">// TODO: adjust viewport and canvas</span><span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">  </span>}<span style="color: #bbbbbb"></span>
-}<span style="color: #bbbbbb"></span>
+<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #008000; font-weight: bold">class</span><span style="color: #BBB"> </span>App<span style="color: #BBB"> </span>{
+<span style="color: #BBB">  </span><span style="color: #008000; font-weight: bold">constructor</span>()<span style="color: #BBB"> </span>{
+<span style="color: #BBB">    </span><span style="color: #3D7B7B; font-style: italic">// TODO: create entities</span>
+<span style="color: #BBB">    </span><span style="color: #008000; font-weight: bold">this</span>.render<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #008000; font-weight: bold">this</span>.render.bind(<span style="color: #008000; font-weight: bold">this</span>);
+<span style="color: #BBB">    </span><span style="color: #008000; font-weight: bold">this</span>.resize<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #008000; font-weight: bold">this</span>.resize.bind(<span style="color: #008000; font-weight: bold">this</span>);
+<span style="color: #BBB">    </span><span style="color: #008000">window</span>.addEventListener(<span style="color: #BA2121">&#39;resize&#39;</span>,<span style="color: #BBB"> </span><span style="color: #008000; font-weight: bold">this</span>.resize);
+<span style="color: #BBB">    </span><span style="color: #008000">window</span>.requestAnimationFrame(<span style="color: #008000; font-weight: bold">this</span>.render);
+<span style="color: #BBB">  </span>}
+<span style="color: #BBB">  </span>render()<span style="color: #BBB"> </span>{
+<span style="color: #BBB">    </span><span style="color: #3D7B7B; font-style: italic">// TODO: render scene</span>
+<span style="color: #BBB">    </span><span style="color: #008000">window</span>.requestAnimationFrame(<span style="color: #008000; font-weight: bold">this</span>.render);
+<span style="color: #BBB">  </span>}
+<span style="color: #BBB">  </span>resize()<span style="color: #BBB"> </span>{
+<span style="color: #BBB">    </span><span style="color: #3D7B7B; font-style: italic">// TODO: adjust viewport and canvas</span>
+<span style="color: #BBB">  </span>}
+}
 
-Filament.init([<span style="color: #BA2121">&#39;triangle.filamat&#39;</span>],<span style="color: #bbbbbb"> </span>()<span style="color: #bbbbbb"> </span>=&gt;<span style="color: #bbbbbb"> </span>{<span style="color: #bbbbbb"> </span><span style="color: #008000">window</span>.app<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #AA22FF; font-weight: bold">new</span><span style="color: #bbbbbb"> </span>App()<span style="color: #bbbbbb"> </span>}<span style="color: #bbbbbb"> </span>);<span style="color: #bbbbbb"></span>
+Filament.init([<span style="color: #BA2121">&#39;triangle.filamat&#39;</span>],<span style="color: #BBB"> </span>()<span style="color: #BBB"> </span>=&gt;<span style="color: #BBB"> </span>{<span style="color: #BBB"> </span><span style="color: #008000">window</span>.app<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #A2F; font-weight: bold">new</span><span style="color: #BBB"> </span>App()<span style="color: #BBB"> </span>}<span style="color: #BBB"> </span>);
 </pre></div>
 
 <p>The two calls to <code>bind()</code> allow us to pass instance methods as callbacks for animation and resize
 events.</p>
 <p><code>Filament.init()</code> consumes two things: a list of asset URLs and a callback.</p>
 <p>The callback will be triggered only after all assets finish downloading and the Filament module has
-become ready. In our callback, we simply instantiated the <code>App</code> object, since we&#x27;ll do most of the
+become ready. In our callback, we simply instantiated the <code>App</code> object, since we'll do most of the
 work in its constructor. We also set the app instance into a <code>Window</code> property to make it accessible
 from the developer console.</p>
 <p>Go ahead and download <a href="triangle.filamat">triangle.filamat</a> and place it in your project folder.
 This is a <em>material package</em>, which is a binary file that contains shaders and other bits of data
-that define a PBR material. We&#x27;ll learn more about material packages in the next tutorial.</p>
+that define a PBR material. We'll learn more about material packages in the next tutorial.</p>
 <h2>Spawn a local server</h2>
 <p>Because of CORS restrictions, your web app cannot fetch the material package directly from the
 file system. One way around this is to create a temporary server using Python or node:</p>
-<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span>python3 -m http.server     <span style="color: #3D7B7B; font-style: italic"># Python 3</span>
-python -m SimpleHTTPServer <span style="color: #3D7B7B; font-style: italic"># Python 2.7</span>
-npx http-server -p <span style="color: #666666">8000</span>    <span style="color: #3D7B7B; font-style: italic"># nodejs</span>
+<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span>python3<span style="color: #BBB"> </span>-m<span style="color: #BBB"> </span>http.server<span style="color: #BBB">     </span><span style="color: #3D7B7B; font-style: italic"># Python 3</span>
+python<span style="color: #BBB"> </span>-m<span style="color: #BBB"> </span>SimpleHTTPServer<span style="color: #BBB"> </span><span style="color: #3D7B7B; font-style: italic"># Python 2.7</span>
+npx<span style="color: #BBB"> </span>http-server<span style="color: #BBB"> </span>-p<span style="color: #BBB"> </span><span style="color: #666">8000</span><span style="color: #BBB">    </span><span style="color: #3D7B7B; font-style: italic"># nodejs</span>
 </pre></div>
 
 <p>To see if this works, navigate to <a href="http://localhost:8000">http://localhost:8000</a> and check if you
 can load the page without any errors appearing in the developer console.</p>
-<p>Take care not to use Python&#x27;s simple server in production since it does not serve WebAssembly files
+<p>Take care not to use Python's simple server in production since it does not serve WebAssembly files
 with the correct MIME type.</p>
 <h2>Create the Engine and Scene</h2>
-<p>We now have a basic skeleton that can respond to paint and resize events. Let&#x27;s start adding
+<p>We now have a basic skeleton that can respond to paint and resize events. Let's start adding
 Filament objects to the app. Insert the following code into the top of the app constructor.</p>
-<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #008000; font-weight: bold">this</span>.canvas<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000">document</span>.getElementsByTagName(<span style="color: #BA2121">&#39;canvas&#39;</span>)[<span style="color: #666666">0</span>];<span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>engine<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.engine<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>Filament.Engine.create(<span style="color: #008000; font-weight: bold">this</span>.canvas);<span style="color: #bbbbbb"></span>
+<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #008000; font-weight: bold">this</span>.canvas<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #008000">document</span>.getElementsByTagName(<span style="color: #BA2121">&#39;canvas&#39;</span>)[<span style="color: #666">0</span>];
+<span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>engine<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #008000; font-weight: bold">this</span>.engine<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>Filament.Engine.create(<span style="color: #008000; font-weight: bold">this</span>.canvas);
 </pre></div>
 
 <p>The above snippet creates the <code>Engine</code> by passing it a canvas DOM object. The engine needs the
 canvas in order to create a WebGL 2.0 context in its contructor.</p>
 <p>The engine is a factory for many Filament entities, including <code>Scene</code>, which is a flat container of
-entities. Let&#x27;s go ahead and create a scene, then add a blank entity called <code>triangle</code> into the
+entities. Let's go ahead and create a scene, then add a blank entity called <code>triangle</code> into the
 scene.</p>
-<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #008000; font-weight: bold">this</span>.scene<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>engine.createScene();<span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">this</span>.triangle<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>Filament.EntityManager.get().create();<span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">this</span>.scene.addEntity(<span style="color: #008000; font-weight: bold">this</span>.triangle);<span style="color: #bbbbbb"></span>
+<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #008000; font-weight: bold">this</span>.scene<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>engine.createScene();
+<span style="color: #008000; font-weight: bold">this</span>.triangle<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>Filament.EntityManager.get().create();
+<span style="color: #008000; font-weight: bold">this</span>.scene.addEntity(<span style="color: #008000; font-weight: bold">this</span>.triangle);
 </pre></div>
 
 <p>Filament uses an <a href="//en.wikipedia.org/wiki/Entity-component-system">Entity-Component System</a>.
@@ -112,30 +112,30 @@ The triangle entity in the above snippet does not yet have an associated compone
 tutorial we will make it into a <em>renderable</em>. Renderables are entities that have associated draw
 calls.</p>
 <h2>Construct typed arrays</h2>
-<p>Next we&#x27;ll create two typed arrays: a positions array with XY coordinates for each vertex, and a
+<p>Next we'll create two typed arrays: a positions array with XY coordinates for each vertex, and a
 colors array with a 32-bit word for each vertex.</p>
-<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>TRIANGLE_POSITIONS<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #AA22FF; font-weight: bold">new</span><span style="color: #bbbbbb"> </span><span style="color: #008000">Float32Array</span>([<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #666666">1</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">0</span>,<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #008000">Math</span>.cos(<span style="color: #008000">Math</span>.PI<span style="color: #bbbbbb"> </span><span style="color: #666666">*</span><span style="color: #bbbbbb"> </span><span style="color: #666666">2</span><span style="color: #bbbbbb"> </span><span style="color: #666666">/</span><span style="color: #bbbbbb"> </span><span style="color: #666666">3</span>),<span style="color: #bbbbbb"> </span><span style="color: #008000">Math</span>.sin(<span style="color: #008000">Math</span>.PI<span style="color: #bbbbbb"> </span><span style="color: #666666">*</span><span style="color: #bbbbbb"> </span><span style="color: #666666">2</span><span style="color: #bbbbbb"> </span><span style="color: #666666">/</span><span style="color: #bbbbbb"> </span><span style="color: #666666">3</span>),<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #008000">Math</span>.cos(<span style="color: #008000">Math</span>.PI<span style="color: #bbbbbb"> </span><span style="color: #666666">*</span><span style="color: #bbbbbb"> </span><span style="color: #666666">4</span><span style="color: #bbbbbb"> </span><span style="color: #666666">/</span><span style="color: #bbbbbb"> </span><span style="color: #666666">3</span>),<span style="color: #bbbbbb"> </span><span style="color: #008000">Math</span>.sin(<span style="color: #008000">Math</span>.PI<span style="color: #bbbbbb"> </span><span style="color: #666666">*</span><span style="color: #bbbbbb"> </span><span style="color: #666666">4</span><span style="color: #bbbbbb"> </span><span style="color: #666666">/</span><span style="color: #bbbbbb"> </span><span style="color: #666666">3</span>),<span style="color: #bbbbbb"></span>
-]);<span style="color: #bbbbbb"></span>
+<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>TRIANGLE_POSITIONS<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #A2F; font-weight: bold">new</span><span style="color: #BBB"> </span><span style="color: #008000">Float32Array</span>([
+<span style="color: #BBB">    </span><span style="color: #666">1</span>,<span style="color: #BBB"> </span><span style="color: #666">0</span>,
+<span style="color: #BBB">    </span><span style="color: #008000">Math</span>.cos(<span style="color: #008000">Math</span>.PI<span style="color: #BBB"> </span><span style="color: #666">*</span><span style="color: #BBB"> </span><span style="color: #666">2</span><span style="color: #BBB"> </span><span style="color: #666">/</span><span style="color: #BBB"> </span><span style="color: #666">3</span>),<span style="color: #BBB"> </span><span style="color: #008000">Math</span>.sin(<span style="color: #008000">Math</span>.PI<span style="color: #BBB"> </span><span style="color: #666">*</span><span style="color: #BBB"> </span><span style="color: #666">2</span><span style="color: #BBB"> </span><span style="color: #666">/</span><span style="color: #BBB"> </span><span style="color: #666">3</span>),
+<span style="color: #BBB">    </span><span style="color: #008000">Math</span>.cos(<span style="color: #008000">Math</span>.PI<span style="color: #BBB"> </span><span style="color: #666">*</span><span style="color: #BBB"> </span><span style="color: #666">4</span><span style="color: #BBB"> </span><span style="color: #666">/</span><span style="color: #BBB"> </span><span style="color: #666">3</span>),<span style="color: #BBB"> </span><span style="color: #008000">Math</span>.sin(<span style="color: #008000">Math</span>.PI<span style="color: #BBB"> </span><span style="color: #666">*</span><span style="color: #BBB"> </span><span style="color: #666">4</span><span style="color: #BBB"> </span><span style="color: #666">/</span><span style="color: #BBB"> </span><span style="color: #666">3</span>),
+]);
 
-<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>TRIANGLE_COLORS<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #AA22FF; font-weight: bold">new</span><span style="color: #bbbbbb"> </span><span style="color: #008000">Uint32Array</span>([<span style="color: #666666">0xffff0000</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">0xff00ff00</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">0xff0000ff</span>]);<span style="color: #bbbbbb"></span>
+<span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>TRIANGLE_COLORS<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #A2F; font-weight: bold">new</span><span style="color: #BBB"> </span><span style="color: #008000">Uint32Array</span>([<span style="color: #666">0xffff0000</span>,<span style="color: #BBB"> </span><span style="color: #666">0xff00ff00</span>,<span style="color: #BBB"> </span><span style="color: #666">0xff0000ff</span>]);
 </pre></div>
 
-<p>Next we&#x27;ll use the positions and colors buffers to create a single <code>VertexBuffer</code> object.</p>
-<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>VertexAttribute<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>Filament.VertexAttribute;<span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>AttributeType<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>Filament.VertexBuffer$AttributeType;<span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">this</span>.vb<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>Filament.VertexBuffer.Builder()<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span>.vertexCount(<span style="color: #666666">3</span>)<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span>.bufferCount(<span style="color: #666666">2</span>)<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span>.attribute(VertexAttribute.POSITION,<span style="color: #bbbbbb"> </span><span style="color: #666666">0</span>,<span style="color: #bbbbbb"> </span>AttributeType.FLOAT2,<span style="color: #bbbbbb"> </span><span style="color: #666666">0</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">8</span>)<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span>.attribute(VertexAttribute.COLOR,<span style="color: #bbbbbb"> </span><span style="color: #666666">1</span>,<span style="color: #bbbbbb"> </span>AttributeType.UBYTE4,<span style="color: #bbbbbb"> </span><span style="color: #666666">0</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">4</span>)<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span>.normalized(VertexAttribute.COLOR)<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span>.build(engine);<span style="color: #bbbbbb"></span>
+<p>Next we'll use the positions and colors buffers to create a single <code>VertexBuffer</code> object.</p>
+<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>VertexAttribute<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>Filament.VertexAttribute;
+<span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>AttributeType<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>Filament.VertexBuffer$AttributeType;
+<span style="color: #008000; font-weight: bold">this</span>.vb<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>Filament.VertexBuffer.Builder()
+<span style="color: #BBB">    </span>.vertexCount(<span style="color: #666">3</span>)
+<span style="color: #BBB">    </span>.bufferCount(<span style="color: #666">2</span>)
+<span style="color: #BBB">    </span>.attribute(VertexAttribute.POSITION,<span style="color: #BBB"> </span><span style="color: #666">0</span>,<span style="color: #BBB"> </span>AttributeType.FLOAT2,<span style="color: #BBB"> </span><span style="color: #666">0</span>,<span style="color: #BBB"> </span><span style="color: #666">8</span>)
+<span style="color: #BBB">    </span>.attribute(VertexAttribute.COLOR,<span style="color: #BBB"> </span><span style="color: #666">1</span>,<span style="color: #BBB"> </span>AttributeType.UBYTE4,<span style="color: #BBB"> </span><span style="color: #666">0</span>,<span style="color: #BBB"> </span><span style="color: #666">4</span>)
+<span style="color: #BBB">    </span>.normalized(VertexAttribute.COLOR)
+<span style="color: #BBB">    </span>.build(engine);
 
-<span style="color: #008000; font-weight: bold">this</span>.vb.setBufferAt(engine,<span style="color: #bbbbbb"> </span><span style="color: #666666">0</span>,<span style="color: #bbbbbb"> </span>TRIANGLE_POSITIONS);<span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">this</span>.vb.setBufferAt(engine,<span style="color: #bbbbbb"> </span><span style="color: #666666">1</span>,<span style="color: #bbbbbb"> </span>TRIANGLE_COLORS);<span style="color: #bbbbbb"></span>
+<span style="color: #008000; font-weight: bold">this</span>.vb.setBufferAt(engine,<span style="color: #BBB"> </span><span style="color: #666">0</span>,<span style="color: #BBB"> </span>TRIANGLE_POSITIONS);
+<span style="color: #008000; font-weight: bold">this</span>.vb.setBufferAt(engine,<span style="color: #BBB"> </span><span style="color: #666">1</span>,<span style="color: #BBB"> </span>TRIANGLE_COLORS);
 </pre></div>
 
 <p>The above snippet first creates aliases for two enum types, then constructs the vertex buffer using
@@ -147,74 +147,74 @@ self-documenting.</p>
 <p>Our app sets up two buffer slots in the vertex buffer, and each slot is associated with a single
 attribute. Alternatively, we could have interleaved or concatenated these attributes into a single
 buffer slot.</p>
-<p>Next we&#x27;ll construct an index buffer. The index buffer for our triangle is trivial: it simply holds
+<p>Next we'll construct an index buffer. The index buffer for our triangle is trivial: it simply holds
 the integers 0,1,2.</p>
-<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #008000; font-weight: bold">this</span>.ib<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>Filament.IndexBuffer.Builder()<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span>.indexCount(<span style="color: #666666">3</span>)<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span>.bufferType(Filament.IndexBuffer$IndexType.USHORT)<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span>.build(engine);<span style="color: #bbbbbb"></span>
+<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #008000; font-weight: bold">this</span>.ib<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>Filament.IndexBuffer.Builder()
+<span style="color: #BBB">    </span>.indexCount(<span style="color: #666">3</span>)
+<span style="color: #BBB">    </span>.bufferType(Filament.IndexBuffer$IndexType.USHORT)
+<span style="color: #BBB">    </span>.build(engine);
 
-<span style="color: #008000; font-weight: bold">this</span>.ib.setBuffer(engine,<span style="color: #bbbbbb"> </span><span style="color: #AA22FF; font-weight: bold">new</span><span style="color: #bbbbbb"> </span><span style="color: #008000">Uint16Array</span>([<span style="color: #666666">0</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">1</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">2</span>]));<span style="color: #bbbbbb"></span>
+<span style="color: #008000; font-weight: bold">this</span>.ib.setBuffer(engine,<span style="color: #BBB"> </span><span style="color: #A2F; font-weight: bold">new</span><span style="color: #BBB"> </span><span style="color: #008000">Uint16Array</span>([<span style="color: #666">0</span>,<span style="color: #BBB"> </span><span style="color: #666">1</span>,<span style="color: #BBB"> </span><span style="color: #666">2</span>]));
 </pre></div>
 
 <p>Note that constructing an index buffer is similar to constructing a vertex buffer, but it only has
 one buffer slot, and it can only contain two types of data (USHORT or UINT).</p>
 <h2>Finish up initialization</h2>
-<p>Next let&#x27;s construct an actual <code>Material</code> from the material package that was downloaded (the
+<p>Next let's construct an actual <code>Material</code> from the material package that was downloaded (the
 material is an object; the package is just a binary blob), then extract the default
 <code>MaterialInstance</code> from the material object. Material instances have concrete values for their
-parameters, and they can be bound to renderables. We&#x27;ll learn more about material instances in the
+parameters, and they can be bound to renderables. We'll learn more about material instances in the
 next tutorial.</p>
 <p>After extracting the material instance, we can finally create a renderable component for the
 triangle by setting up a bounding box and passing in the vertex and index buffers.</p>
-<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>mat<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>engine.createMaterial(<span style="color: #BA2121">&#39;triangle.filamat&#39;</span>);<span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>matinst<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>mat.getDefaultInstance();<span style="color: #bbbbbb"></span>
-Filament.RenderableManager.Builder(<span style="color: #666666">1</span>)<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span>.boundingBox({<span style="color: #bbbbbb"> </span>center<span style="color: #666666">:</span><span style="color: #bbbbbb"> </span>[<span style="color: #666666">-1</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">-1</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">-1</span>],<span style="color: #bbbbbb"> </span>halfExtent<span style="color: #666666">:</span><span style="color: #bbbbbb"> </span>[<span style="color: #666666">1</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">1</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">1</span>]<span style="color: #bbbbbb"> </span>})<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span>.material(<span style="color: #666666">0</span>,<span style="color: #bbbbbb"> </span>matinst)<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span>.geometry(<span style="color: #666666">0</span>,<span style="color: #bbbbbb"> </span>Filament.RenderableManager$PrimitiveType.TRIANGLES,<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.vb,<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.ib)<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span>.build(engine,<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.triangle);<span style="color: #bbbbbb"></span>
+<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>mat<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>engine.createMaterial(<span style="color: #BA2121">&#39;triangle.filamat&#39;</span>);
+<span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>matinst<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>mat.getDefaultInstance();
+Filament.RenderableManager.Builder(<span style="color: #666">1</span>)
+<span style="color: #BBB">    </span>.boundingBox({<span style="color: #BBB"> </span>center<span style="color: #666">:</span><span style="color: #BBB"> </span>[<span style="color: #666">-1</span>,<span style="color: #BBB"> </span><span style="color: #666">-1</span>,<span style="color: #BBB"> </span><span style="color: #666">-1</span>],<span style="color: #BBB"> </span>halfExtent<span style="color: #666">:</span><span style="color: #BBB"> </span>[<span style="color: #666">1</span>,<span style="color: #BBB"> </span><span style="color: #666">1</span>,<span style="color: #BBB"> </span><span style="color: #666">1</span>]<span style="color: #BBB"> </span>})
+<span style="color: #BBB">    </span>.material(<span style="color: #666">0</span>,<span style="color: #BBB"> </span>matinst)
+<span style="color: #BBB">    </span>.geometry(<span style="color: #666">0</span>,<span style="color: #BBB"> </span>Filament.RenderableManager$PrimitiveType.TRIANGLES,<span style="color: #BBB"> </span><span style="color: #008000; font-weight: bold">this</span>.vb,<span style="color: #BBB"> </span><span style="color: #008000; font-weight: bold">this</span>.ib)
+<span style="color: #BBB">    </span>.build(engine,<span style="color: #BBB"> </span><span style="color: #008000; font-weight: bold">this</span>.triangle);
 </pre></div>
 
-<p>Next let&#x27;s wrap up the initialization routine by creating the swap chain, renderer, camera, and
+<p>Next let's wrap up the initialization routine by creating the swap chain, renderer, camera, and
 view.</p>
-<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #008000; font-weight: bold">this</span>.swapChain<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>engine.createSwapChain();<span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">this</span>.renderer<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>engine.createRenderer();<span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">this</span>.camera<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>engine.createCamera(Filament.EntityManager.get().create());<span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">this</span>.view<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>engine.createView();<span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">this</span>.view.setCamera(<span style="color: #008000; font-weight: bold">this</span>.camera);<span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">this</span>.view.setScene(<span style="color: #008000; font-weight: bold">this</span>.scene);<span style="color: #bbbbbb"></span>
+<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #008000; font-weight: bold">this</span>.swapChain<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>engine.createSwapChain();
+<span style="color: #008000; font-weight: bold">this</span>.renderer<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>engine.createRenderer();
+<span style="color: #008000; font-weight: bold">this</span>.camera<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>engine.createCamera(Filament.EntityManager.get().create());
+<span style="color: #008000; font-weight: bold">this</span>.view<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>engine.createView();
+<span style="color: #008000; font-weight: bold">this</span>.view.setCamera(<span style="color: #008000; font-weight: bold">this</span>.camera);
+<span style="color: #008000; font-weight: bold">this</span>.view.setScene(<span style="color: #008000; font-weight: bold">this</span>.scene);
 
-<span style="color: #3D7B7B; font-style: italic">// Set up a blue-green background:</span><span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">this</span>.renderer.setClearOptions({clearColor<span style="color: #666666">:</span><span style="color: #bbbbbb"> </span>[<span style="color: #666666">0.0</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">0.1</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">0.2</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">1.0</span>],<span style="color: #bbbbbb"> </span>clear<span style="color: #666666">:</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">true</span>});<span style="color: #bbbbbb"></span>
+<span style="color: #3D7B7B; font-style: italic">// Set up a blue-green background:</span>
+<span style="color: #008000; font-weight: bold">this</span>.renderer.setClearOptions({clearColor<span style="color: #666">:</span><span style="color: #BBB"> </span>[<span style="color: #666">0.0</span>,<span style="color: #BBB"> </span><span style="color: #666">0.1</span>,<span style="color: #BBB"> </span><span style="color: #666">0.2</span>,<span style="color: #BBB"> </span><span style="color: #666">1.0</span>],<span style="color: #BBB"> </span>clear<span style="color: #666">:</span><span style="color: #BBB"> </span><span style="color: #008000; font-weight: bold">true</span>});
 
-<span style="color: #3D7B7B; font-style: italic">// Adjust the initial viewport:</span><span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">this</span>.resize();<span style="color: #bbbbbb"></span>
+<span style="color: #3D7B7B; font-style: italic">// Adjust the initial viewport:</span>
+<span style="color: #008000; font-weight: bold">this</span>.resize();
 </pre></div>
 
-<p>At this point, we&#x27;re done creating all Filament entities, and the code should run without errors.
+<p>At this point, we're done creating all Filament entities, and the code should run without errors.
 However the canvas is still blank!</p>
 <h2>Render and resize handlers</h2>
 <p>Recall that our App class has a skeletal render method, which the browser calls every time it needs
 to repaint. Often this is 60 times a second.</p>
-<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span>render()<span style="color: #bbbbbb"> </span>{<span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #3D7B7B; font-style: italic">// TODO: render scene</span><span style="color: #bbbbbb"></span>
-<span style="color: #bbbbbb">    </span><span style="color: #008000">window</span>.requestAnimationFrame(<span style="color: #008000; font-weight: bold">this</span>.render);<span style="color: #bbbbbb"></span>
-}<span style="color: #bbbbbb"></span>
+<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span>render()<span style="color: #BBB"> </span>{
+<span style="color: #BBB">    </span><span style="color: #3D7B7B; font-style: italic">// TODO: render scene</span>
+<span style="color: #BBB">    </span><span style="color: #008000">window</span>.requestAnimationFrame(<span style="color: #008000; font-weight: bold">this</span>.render);
+}
 </pre></div>
 
-<p>Let&#x27;s flesh this out by rotating the triangle and invoking the Filament renderer. Add the following
+<p>Let's flesh this out by rotating the triangle and invoking the Filament renderer. Add the following
 code to the top of the render method.</p>
-<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #3D7B7B; font-style: italic">// Rotate the triangle.</span><span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>radians<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000">Date</span>.now()<span style="color: #bbbbbb"> </span><span style="color: #666666">/</span><span style="color: #bbbbbb"> </span><span style="color: #666666">1000</span>;<span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>transform<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>mat4.fromRotation(mat4.create(),<span style="color: #bbbbbb"> </span>radians,<span style="color: #bbbbbb"> </span>[<span style="color: #666666">0</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">0</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">1</span>]);<span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>tcm<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.getTransformManager();<span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>inst<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>tcm.getInstance(<span style="color: #008000; font-weight: bold">this</span>.triangle);<span style="color: #bbbbbb"></span>
-tcm.setTransform(inst,<span style="color: #bbbbbb"> </span>transform);<span style="color: #bbbbbb"></span>
-inst.<span style="color: #AA22FF; font-weight: bold">delete</span>();<span style="color: #bbbbbb"></span>
+<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #3D7B7B; font-style: italic">// Rotate the triangle.</span>
+<span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>radians<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #008000">Date</span>.now()<span style="color: #BBB"> </span><span style="color: #666">/</span><span style="color: #BBB"> </span><span style="color: #666">1000</span>;
+<span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>transform<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>mat4.fromRotation(mat4.create(),<span style="color: #BBB"> </span>radians,<span style="color: #BBB"> </span>[<span style="color: #666">0</span>,<span style="color: #BBB"> </span><span style="color: #666">0</span>,<span style="color: #BBB"> </span><span style="color: #666">1</span>]);
+<span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>tcm<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.getTransformManager();
+<span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>inst<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>tcm.getInstance(<span style="color: #008000; font-weight: bold">this</span>.triangle);
+tcm.setTransform(inst,<span style="color: #BBB"> </span>transform);
+inst.<span style="color: #A2F; font-weight: bold">delete</span>();
 
-<span style="color: #3D7B7B; font-style: italic">// Render the frame.</span><span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">this</span>.renderer.render(<span style="color: #008000; font-weight: bold">this</span>.swapChain,<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.view);<span style="color: #bbbbbb"></span>
+<span style="color: #3D7B7B; font-style: italic">// Render the frame.</span>
+<span style="color: #008000; font-weight: bold">this</span>.renderer.render(<span style="color: #008000; font-weight: bold">this</span>.swapChain,<span style="color: #BBB"> </span><span style="color: #008000; font-weight: bold">this</span>.view);
 </pre></div>
 
 <p>The first half of our render method obtains the transform component of the triangle entity and uses
@@ -225,19 +225,19 @@ that it wants to skip a frame, hence the <code>if</code> statement.</p>
 <p>One last step. Add the following code to the resize method. This adjusts the resolution of the
 rendering surface when the window size changes, taking <code>devicePixelRatio</code> into account for high-DPI
 displays. It also adjusts the camera frustum accordingly.</p>
-<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>dpr<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000">window</span>.devicePixelRatio;<span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>width<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.canvas.width<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000">window</span>.innerWidth<span style="color: #bbbbbb"> </span><span style="color: #666666">*</span><span style="color: #bbbbbb"> </span>dpr;<span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>height<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.canvas.height<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000">window</span>.innerHeight<span style="color: #bbbbbb"> </span><span style="color: #666666">*</span><span style="color: #bbbbbb"> </span>dpr;<span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">this</span>.view.setViewport([<span style="color: #666666">0</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">0</span>,<span style="color: #bbbbbb"> </span>width,<span style="color: #bbbbbb"> </span>height]);<span style="color: #bbbbbb"></span>
+<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>dpr<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #008000">window</span>.devicePixelRatio;
+<span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>width<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #008000; font-weight: bold">this</span>.canvas.width<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #008000">window</span>.innerWidth<span style="color: #BBB"> </span><span style="color: #666">*</span><span style="color: #BBB"> </span>dpr;
+<span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>height<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #008000; font-weight: bold">this</span>.canvas.height<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span><span style="color: #008000">window</span>.innerHeight<span style="color: #BBB"> </span><span style="color: #666">*</span><span style="color: #BBB"> </span>dpr;
+<span style="color: #008000; font-weight: bold">this</span>.view.setViewport([<span style="color: #666">0</span>,<span style="color: #BBB"> </span><span style="color: #666">0</span>,<span style="color: #BBB"> </span>width,<span style="color: #BBB"> </span>height]);
 
-<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>aspect<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>width<span style="color: #bbbbbb"> </span><span style="color: #666666">/</span><span style="color: #bbbbbb"> </span>height;<span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>Projection<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>Filament.Camera$Projection;<span style="color: #bbbbbb"></span>
-<span style="color: #008000; font-weight: bold">this</span>.camera.setProjection(Projection.ORTHO,<span style="color: #bbbbbb"> </span><span style="color: #666666">-</span>aspect,<span style="color: #bbbbbb"> </span>aspect,<span style="color: #bbbbbb"> </span><span style="color: #666666">-1</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">1</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">0</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">1</span>);<span style="color: #bbbbbb"></span>
+<span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>aspect<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>width<span style="color: #BBB"> </span><span style="color: #666">/</span><span style="color: #BBB"> </span>height;
+<span style="color: #008000; font-weight: bold">const</span><span style="color: #BBB"> </span>Projection<span style="color: #BBB"> </span><span style="color: #666">=</span><span style="color: #BBB"> </span>Filament.Camera$Projection;
+<span style="color: #008000; font-weight: bold">this</span>.camera.setProjection(Projection.ORTHO,<span style="color: #BBB"> </span><span style="color: #666">-</span>aspect,<span style="color: #BBB"> </span>aspect,<span style="color: #BBB"> </span><span style="color: #666">-1</span>,<span style="color: #BBB"> </span><span style="color: #666">1</span>,<span style="color: #BBB"> </span><span style="color: #666">0</span>,<span style="color: #BBB"> </span><span style="color: #666">1</span>);
 </pre></div>
 
 <p>You should now have a spinning triangle! The completed JavaScript is available
 <a href="tutorial_triangle.js">here</a>.</p>
-<p>In the <a href="tutorial_redball.html">next tutorial</a>, we&#x27;ll take a closer look at Filament materials and 3D rendering.</p>
+<p>In the <a href="tutorial_redball.html">next tutorial</a>, we'll take a closer look at Filament materials and 3D rendering.</p>
 
 </body>
 </html>

filament/backend/CMakeLists.txt

@@ -5,6 +5,18 @@ set(TARGET backend)
 set(PUBLIC_HDR_DIR include)
 set(GENERATION_ROOT ${CMAKE_CURRENT_BINARY_DIR})
 
+# ==================================================================================================
+# Compilation options
+# ==================================================================================================
+#
+set(BACKEND_SANITIZATION "" CACHE STRING "Sanitization option")
+set_property(CACHE BACKEND_SANITIZATION PROPERTY STRINGS ";ASAN")
+
+set(BACKEND_SANITIZERS)
+if (BACKEND_SANITIZATION STREQUAL "ASAN")
+    set(BACKEND_SANITIZERS -fsanitize=address)
+endif()
+
 # ==================================================================================================
 # Sources and headers
 # ==================================================================================================
@@ -177,29 +189,6 @@ endif()
 if (FILAMENT_SUPPORTS_VULKAN)
     list(APPEND SRCS
             include/backend/platforms/VulkanPlatform.h
-            src/vulkan/VulkanDescriptorSetCache.cpp
-            src/vulkan/VulkanDescriptorSetCache.h
-            src/vulkan/VulkanDescriptorSetLayoutCache.cpp
-            src/vulkan/VulkanDescriptorSetLayoutCache.h
-            src/vulkan/VulkanPipelineLayoutCache.cpp
-            src/vulkan/VulkanPipelineLayoutCache.h
-            src/vulkan/memory/ResourceManager.cpp
-            src/vulkan/memory/ResourceManager.h
-            src/vulkan/memory/ResourcePointer.h
-            src/vulkan/memory/Resource.cpp
-            src/vulkan/memory/Resource.h
-            src/vulkan/platform/VulkanPlatform.cpp
-            src/vulkan/platform/VulkanPlatformSwapChainImpl.cpp
-            src/vulkan/platform/VulkanPlatformSwapChainImpl.h
-            src/vulkan/utils/Conversion.cpp
-            src/vulkan/utils/Conversion.h
-            src/vulkan/utils/Definitions.h
-            src/vulkan/utils/Helper.h
-            src/vulkan/utils/Image.h
-            src/vulkan/utils/Image.cpp
-            src/vulkan/utils/Spirv.h
-            src/vulkan/utils/Spirv.cpp
-            src/vulkan/utils/StaticVector.h
             src/vulkan/VulkanAsyncHandles.h
             src/vulkan/VulkanBlitter.cpp
             src/vulkan/VulkanBlitter.h
@@ -210,29 +199,56 @@ if (FILAMENT_SUPPORTS_VULKAN)
             src/vulkan/VulkanConstants.h
             src/vulkan/VulkanContext.cpp
             src/vulkan/VulkanContext.h
+            src/vulkan/VulkanDescriptorSetCache.cpp
+            src/vulkan/VulkanDescriptorSetCache.h
+            src/vulkan/VulkanDescriptorSetLayoutCache.cpp
+            src/vulkan/VulkanDescriptorSetLayoutCache.h
             src/vulkan/VulkanDriver.cpp
             src/vulkan/VulkanDriver.h
             src/vulkan/VulkanDriverFactory.h
+            src/vulkan/VulkanExternalImageManager.cpp
+            src/vulkan/VulkanExternalImageManager.h
             src/vulkan/VulkanFboCache.cpp
             src/vulkan/VulkanFboCache.h
             src/vulkan/VulkanHandles.cpp
             src/vulkan/VulkanHandles.h
-            src/vulkan/VulkanMemory.h
             src/vulkan/VulkanMemory.cpp
+            src/vulkan/VulkanMemory.h
             src/vulkan/VulkanPipelineCache.cpp
             src/vulkan/VulkanPipelineCache.h
+            src/vulkan/VulkanPipelineLayoutCache.cpp
+            src/vulkan/VulkanPipelineLayoutCache.h
             src/vulkan/VulkanQueryManager.cpp
             src/vulkan/VulkanQueryManager.h
+            src/vulkan/VulkanReadPixels.cpp
+            src/vulkan/VulkanReadPixels.h
             src/vulkan/VulkanSamplerCache.cpp
             src/vulkan/VulkanSamplerCache.h
             src/vulkan/VulkanStagePool.cpp
             src/vulkan/VulkanStagePool.h
             src/vulkan/VulkanSwapChain.cpp
             src/vulkan/VulkanSwapChain.h
-            src/vulkan/VulkanReadPixels.cpp
-            src/vulkan/VulkanReadPixels.h
             src/vulkan/VulkanTexture.cpp
             src/vulkan/VulkanTexture.h
+            src/vulkan/VulkanYcbcrConversionCache.cpp
+            src/vulkan/VulkanYcbcrConversionCache.h
+            src/vulkan/memory/Resource.cpp
+            src/vulkan/memory/Resource.h
+            src/vulkan/memory/ResourceManager.cpp
+            src/vulkan/memory/ResourceManager.h
+            src/vulkan/memory/ResourcePointer.h
+            src/vulkan/platform/VulkanPlatform.cpp
+            src/vulkan/platform/VulkanPlatformSwapChainImpl.cpp
+            src/vulkan/platform/VulkanPlatformSwapChainImpl.h
+            src/vulkan/utils/Conversion.cpp
+            src/vulkan/utils/Conversion.h
+            src/vulkan/utils/Definitions.h
+            src/vulkan/utils/Helper.h
+            src/vulkan/utils/Image.cpp
+            src/vulkan/utils/Image.h
+            src/vulkan/utils/Spirv.cpp
+            src/vulkan/utils/Spirv.h
+            src/vulkan/utils/StaticVector.h
     )
     if (LINUX OR WIN32)
         list(APPEND SRCS src/vulkan/platform/VulkanPlatformLinuxWindows.cpp)
@@ -253,6 +269,13 @@ if (FILAMENT_SUPPORTS_WEBGPU)
             src/webgpu/WebGPUConstants.h
             src/webgpu/WebGPUDriver.cpp
             src/webgpu/WebGPUDriver.h
+            src/webgpu/WebGPUHandles.cpp
+            src/webgpu/WebGPUHandles.h
+            src/webgpu/WebGPUPipelineCreation.cpp
+            src/webgpu/WebGPUPipelineCreation.h
+            src/webgpu/WebGPUSwapChain.cpp
+            src/webgpu/WebGPUSwapChain.h
+            src/webgpu/WGPUProgram.cpp
     )
     if (WIN32)
         list(APPEND SRCS src/webgpu/platform/WebGPUPlatformWindows.cpp)
@@ -302,6 +325,11 @@ target_include_directories(${TARGET} PUBLIC ${PUBLIC_HDR_DIR})
 # add this subproject to the Filament folder
 set_target_properties(${TARGET} PROPERTIES FOLDER Filament)
 
+# we need to export the headers properly for backend.lib on windows
+if (WIN32 AND FILAMENT_SUPPORTS_WEBGPU)
+    target_compile_definitions(${TARGET} PRIVATE "WGPU_IMPLEMENTATION")
+endif()
+
 # ==================================================================================================
 # Expose a header-only target to minimize dependencies.
 # ==================================================================================================
@@ -456,6 +484,7 @@ target_compile_options(${TARGET} PRIVATE
         ${OSMESA_COMPILE_FLAGS}
         $<$<CONFIG:Release>:${OPTIMIZATION_FLAGS}>
         $<$<AND:$<PLATFORM_ID:Darwin>,$<CONFIG:Release>>:${DARWIN_OPTIMIZATION_FLAGS}>
+        ${BACKEND_SANITIZERS}
 )
 
 if (FILAMENT_SUPPORTS_METAL)
@@ -466,6 +495,8 @@ if (FILAMENT_SUPPORTS_WEBGPU)
     target_compile_definitions(${TARGET} PRIVATE $<$<BOOL:${FILAMENT_WEBGPU_IMMEDIATE_ERROR_HANDLING}>:FILAMENT_WEBGPU_IMMEDIATE_ERROR_HANDLING>)
 endif()
 
+target_link_options(${TARGET} PRIVATE ${BACKEND_SANITIZERS})
+
 target_link_libraries(${TARGET} PRIVATE
         ${OSMESA_LINKER_FLAGS}
         $<$<AND:$<PLATFORM_ID:Linux>,$<CONFIG:Release>>:${LINUX_LINKER_OPTIMIZATION_FLAGS}>
@@ -496,7 +527,10 @@ if (APPLE OR LINUX)
         test/Arguments.cpp
         test/ImageExpectations.cpp
         test/Lifetimes.cpp
+        test/PlatformRunner.cpp
         test/Shader.cpp
+        test/SharedShaders.cpp
+        test/Skip.cpp
         test/test_FeedbackLoops.cpp
         test/test_Blit.cpp
         test/test_MissingRequiredAttributes.cpp
@@ -520,6 +554,9 @@ if (APPLE OR LINUX)
         filamat
         SPIRV
         spirv-cross-glsl)
+    # Create input/output directories for test result images.
+    file(MAKE_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}/images/actual_images)
+    file(COPY test/expected_images DESTINATION ${CMAKE_CURRENT_BINARY_DIR}/images)
 endif()
 
 # TODO: Disabling IOS test due to breakage wrt glslang update
@@ -529,6 +566,8 @@ if (APPLE AND NOT IOS)
          test/test_RenderExternalImage.cpp)
     add_library(backend_test STATIC ${BACKEND_TEST_SRC})
     target_link_libraries(backend_test PUBLIC ${BACKEND_TEST_LIBS})
+    target_compile_options(backend_test PRIVATE ${BACKEND_SANITIZERS})
+    target_link_options(backend_test PRIVATE ${BACKEND_SANITIZERS})
 
     set(BACKEND_TEST_DEPS
             OSDependent
@@ -567,6 +606,7 @@ if (APPLE AND NOT IOS)
        # linker from removing "unused" symbols.
        target_link_libraries(backend_test_mac PRIVATE -force_load backend_test)
        set_target_properties(backend_test_mac PROPERTIES FOLDER Tests)
+       target_link_options(backend_test_mac PRIVATE ${BACKEND_SANITIZERS})
 
        # This is needed after XCode 15.3
        set_target_properties(backend_test_mac PROPERTIES BUILD_WITH_INSTALL_RPATH TRUE)
@@ -576,6 +616,8 @@ endif()
 
 if (LINUX)
     add_executable(backend_test_linux test/linux_runner.cpp ${BACKEND_TEST_SRC})
+    target_compile_options(backend_test_linux PRIVATE ${BACKEND_SANITIZERS})
+    target_link_options(backend_test_linux PRIVATE ${BACKEND_SANITIZERS})
     target_link_libraries(backend_test_linux PRIVATE ${BACKEND_TEST_LIBS})
     set_target_properties(backend_test_linux PROPERTIES FOLDER Tests)
 endif()

filament/backend/include/backend/BufferObjectStreamDescriptor.h

@@ -55,4 +55,9 @@ public:
 
 } // namespace filament::backend
 
+#if !defined(NDEBUG)
+utils::io::ostream& operator<<(utils::io::ostream& out,
+        const filament::backend::BufferObjectStreamDescriptor& b);
+#endif
+
 #endif // TNT_FILAMENT_BACKEND_BUFFEROBJECTSTREAMDESCRIPTOR_H

filament/backend/include/backend/DriverEnums.h

@@ -39,6 +39,7 @@
 
 #include <stddef.h>
 #include <stdint.h>
+#include <utils/StaticString.h>
 
 /**
  * Types and enums used by filament's driver.
@@ -1139,6 +1140,7 @@ struct ExternalSamplerDatum {
 static_assert(sizeof(ExternalSamplerDatum) == 12);
 
 struct DescriptorSetLayout {
+    std::variant<utils::StaticString, utils::CString, std::monostate> label;
     utils::FixedCapacityVector<DescriptorSetLayoutBinding> bindings;
 
 //  TODO: uncomment when needed
@@ -1455,6 +1457,11 @@ enum class Workaround : uint16_t {
     DISABLE_BLIT_INTO_TEXTURE_ARRAY,
     // Multiple workarounds needed for PowerVR GPUs
     POWER_VR_SHADER_WORKAROUNDS,
+    // Some browsers, such as Firefox on Mac, struggle with slow shader compile/link times when
+    // creating programs for the default material, leading to startup stutters. This workaround
+    // prevents these stutters by not precaching depth variants of the default material for those
+    // particular browsers.
+    DISABLE_DEPTH_PRECACHE_FOR_DEFAULT_MATERIAL,
 };
 
 using StereoscopicType = backend::Platform::StereoscopicType;

filament/backend/include/backend/platforms/VulkanPlatform.h

@@ -104,10 +104,6 @@ public:
 
         // Semaphore to be signaled once the image is available.
         VkSemaphore imageReadySemaphore = VK_NULL_HANDLE;
-
-        // A function called right before vkQueueSubmit. After this call, the image must be 
-        // available. This pointer can be null if imageReadySemaphore is not VK_NULL_HANDLE.
-        std::function<void(SwapChainPtr handle)> explicitImageReadyWait = nullptr;
     };
 
     VulkanPlatform();
@@ -298,6 +294,16 @@ public:
     VkQueue getProtectedGraphicsQueue() const noexcept;
 
     struct ExternalImageMetadata {
+        /**
+         * The Filament texture format.
+         */
+        TextureFormat filamentFormat;
+
+        /**
+         * The Filament texture usage.
+         */
+        TextureUsage filamentUsage;
+
         /**
          * The width of the external image
          */
@@ -308,11 +314,6 @@ public:
          */
         uint32_t height;
 
-        /**
-         * The layerCount of the external image
-         */
-        uint32_t layerCount;
-
         /**
          * The layer count of the external image
          */
@@ -328,11 +329,6 @@ public:
          */
         VkFormat format;
 
-        /**
-         * An external buffer can be protected. This tells you if it is.
-         */
-        bool isProtected;
-
         /**
          * The type of external format (opaque int) if used.
          */
@@ -352,21 +348,61 @@ public:
          * Heap information
          */
         uint32_t memoryTypeBits;
+
+        /**
+         * Ycbcr conversion components
+         */
+        VkComponentMapping ycbcrConversionComponents;
+
+        /**
+         * Ycbcr model
+         */
+        VkSamplerYcbcrModelConversion ycbcrModel;
+
+        /**
+         * Ycbcr range
+         */
+        VkSamplerYcbcrRange ycbcrRange;
+
+        /**
+         * Ycbcr x chroma offset
+         */
+        VkChromaLocation xChromaOffset;
+
+        /**
+         * Ycbcr y chroma offset
+         */
+        VkChromaLocation yChromaOffset;
     };
-    virtual ExternalImageMetadata getExternalImageMetadata(ExternalImageHandleRef externalImage);
 
-    using ImageData = std::pair<VkImage, VkDeviceMemory>;
-    virtual ImageData createExternalImageData(ExternalImageHandleRef externalImage,
-            const ExternalImageMetadata& metadata, uint32_t memoryTypeIndex,
-            VkImageUsageFlags usage);
 
-    virtual VkSampler createExternalSampler(SamplerYcbcrConversion chroma,
-            SamplerParams sampler,
-            uint32_t internalFormat);
+    // Note that the image metadata might change per-frame, hence we need a method for extracting
+    // it.
+    virtual ExternalImageMetadata extractExternalImageMetadata(ExternalImageHandleRef image) const {
+        return {};
+    }
 
-    virtual VkImageView createExternalImageView(SamplerYcbcrConversion chroma,
-            uint32_t internalFormat, VkImage image, VkImageSubresourceRange range,
-            VkImageViewType viewType, VkComponentMapping swizzle);
+    struct ImageData {
+        struct Bundle {
+            VkImage image = VK_NULL_HANDLE;
+            VkDeviceMemory memory = VK_NULL_HANDLE;
+
+            inline bool valid() const noexcept {
+                return image != VK_NULL_HANDLE;
+            }
+        };
+        // It's possible for the external image to also have a known VK format. We need to create an
+        // image for that in case we are not looking to use an external "sampler" with this image.
+        Bundle internal;
+
+        // If we get a externalFormat in the metadata, then we should create an image with
+        // VK_FORMAT_UNDEFINED
+        Bundle external;
+    };
+
+    virtual ImageData createVkImageFromExternal(ExternalImageHandleRef image) const {
+        return {};
+    }
 
 protected:
     virtual ExtensionSet getSwapchainInstanceExtensions() const;
@@ -379,20 +415,6 @@ private:
     // Platform dependent helper methods
     static ExtensionSet getSwapchainInstanceExtensionsImpl();
 
-    static ExternalImageMetadata getExternalImageMetadataImpl(ExternalImageHandleRef externalImage,
-            VkDevice device);
-
-    static ImageData createExternalImageDataImpl(ExternalImageHandleRef externalImage,
-            VkDevice device, const ExternalImageMetadata& metadata, uint32_t memoryTypeIndex,
-            VkImageUsageFlags usage);
-    static VkSampler createExternalSamplerImpl(VkDevice device,
-            SamplerYcbcrConversion chroma, SamplerParams sampler,
-            uint32_t internalFormat);
-    static VkImageView createExternalImageViewImpl(VkDevice device,
-            SamplerYcbcrConversion chroma, uint32_t internalFormat, VkImage image,
-            VkImageSubresourceRange range, VkImageViewType viewType,
-            VkComponentMapping swizzle);
-
     // Platform dependent helper methods
     static SurfaceBundle createVkSurfaceKHRImpl(void* nativeWindow, VkInstance instance,
             uint64_t flags) noexcept;

filament/backend/include/backend/platforms/VulkanPlatformAndroid.h

@@ -26,7 +26,7 @@ namespace filament::backend {
 
 class VulkanPlatformAndroid : public VulkanPlatform {
 public:
-    Platform::ExternalImageHandle UTILS_PUBLIC createExternalImage(AHardwareBuffer const* buffer,
+    ExternalImageHandle UTILS_PUBLIC createExternalImage(AHardwareBuffer const* buffer,
             bool sRGB) noexcept;
 
     struct UTILS_PUBLIC ExternalImageDescAndroid {
@@ -39,31 +39,26 @@ public:
     ExternalImageDescAndroid UTILS_PUBLIC getExternalImageDesc(
             ExternalImageHandleRef externalImage) const noexcept;
 
+    virtual ExternalImageMetadata extractExternalImageMetadata(
+            ExternalImageHandleRef image) const override;
+
+    virtual ImageData createVkImageFromExternal(ExternalImageHandleRef image) const override;
+
 protected:
+    virtual ExtensionSet getSwapchainInstanceExtensions() const override;
+
+    using SurfaceBundle = VulkanPlatform::SurfaceBundle;
+    virtual SurfaceBundle createVkSurfaceKHR(void* nativeWindow, VkInstance instance,
+            uint64_t flags) const noexcept override;
+
+private:
     struct ExternalImageVulkanAndroid : public Platform::ExternalImage {
         AHardwareBuffer* aHardwareBuffer = nullptr;
         bool sRGB = false;
-        unsigned int width;  // Texture width
-        unsigned int height; // Texture height
-        TextureFormat format;// Texture format
-        TextureUsage usage;  // Texture usage flags
 
     protected:
         ~ExternalImageVulkanAndroid() override;
     };
-
-    virtual ExternalImageMetadata getExternalImageMetadata(ExternalImageHandleRef externalImage);
-
-    using ImageData = VulkanPlatform::ImageData;
-    virtual ImageData createExternalImageData(ExternalImageHandleRef externalImage,
-            const ExternalImageMetadata& metadata, uint32_t memoryTypeIndex,
-            VkImageUsageFlags usage);
-
-    virtual ExtensionSet getSwapchainInstanceExtensions() const;
-
-    using SurfaceBundle = VulkanPlatform::SurfaceBundle;
-    virtual SurfaceBundle createVkSurfaceKHR(void* nativeWindow, VkInstance instance,
-            uint64_t flags) const noexcept;
 };
 
 }// namespace filament::backend

filament/backend/include/backend/platforms/WebGPUPlatform.h

@@ -38,6 +38,12 @@ public:
 
     [[nodiscard]] wgpu::Instance& getInstance() noexcept { return mInstance; }
 
+    // TODO consider that this functionality is not WebGPU-specific, and thus could be
+    //      placed in a generic place and even reused across backends. Alternatively,
+    //      a 3rd party library could be considered. However, this was a simple and
+    //      quick change and works for now.
+    // gets the size (height and width) of the surface/window
+    [[nodiscard]] wgpu::Extent2D getSurfaceExtent(void* nativeWindow) const;
     // either returns a valid surface or panics
     [[nodiscard]] wgpu::Surface createSurface(void* nativeWindow, uint64_t flags);
     // either returns a valid adapter or panics

filament/backend/include/private/backend/HandleAllocator.h

@@ -40,9 +40,11 @@
 #include <stddef.h>
 #include <stdint.h>
 
-#define HandleAllocatorGL  HandleAllocator<32,  96, 184>    // ~4520 / pool / MiB
-#define HandleAllocatorVK  HandleAllocator<64, 160, 312>    // ~1820 / pool / MiB
-#define HandleAllocatorMTL HandleAllocator<32,  64, 552>    // ~1660 / pool / MiB
+#define HandleAllocatorGL   HandleAllocator<32,  96, 184>    // ~4520 / pool / MiB
+#define HandleAllocatorVK   HandleAllocator<64, 160, 312>    // ~1820 / pool / MiB
+#define HandleAllocatorMTL  HandleAllocator<32,  64, 552>    // ~1660 / pool / MiB
+// TODO WebGPU examine right size of handles
+#define HandleAllocatorWGPU HandleAllocator<64, 160, 552>    // ~1820 / pool / MiB
 
 namespace filament::backend {
 

filament/backend/src/CommandStream.cpp

@@ -84,7 +84,7 @@ void CommandStream::execute(void* buffer) {
 
     Profiler profiler;
 
-    if (SYSTRACE_TAG) {
+    if constexpr (SYSTRACE_TAG) {
         if (UTILS_UNLIKELY(mUsePerformanceCounter)) {
             // we want to remove all this when tracing is completely disabled
             profiler.resetEvents(Profiler::EV_CPU_CYCLES  | Profiler::EV_BPU_MISSES);
@@ -100,7 +100,7 @@ void CommandStream::execute(void* buffer) {
         }
     });
 
-    if (SYSTRACE_TAG) {
+    if constexpr (SYSTRACE_TAG) {
         if (UTILS_UNLIKELY(mUsePerformanceCounter)) {
             // we want to remove all this when tracing is completely disabled
             profiler.stop();

filament/backend/src/HandleAllocator.cpp

@@ -211,4 +211,8 @@ template class HandleAllocatorVK;
 template class HandleAllocatorMTL;
 #endif
 
+#if defined (FILAMENT_SUPPORTS_WEBGPU)
+template class HandleAllocatorWGPU;
+#endif
+
 } // namespace filament::backend

filament/backend/src/metal/MetalDriver.mm

@@ -1408,8 +1408,8 @@ void MetalDriver::setRenderPrimitiveBuffer(Handle<HwRenderPrimitive> rph, Primit
     auto primitive = handle_cast<MetalRenderPrimitive>(rph);
     auto vertexBuffer = handle_cast<MetalVertexBuffer>(vbh);
     auto indexBuffer = handle_cast<MetalIndexBuffer>(ibh);
-    MetalVertexBufferInfo const* const vbi = handle_cast<MetalVertexBufferInfo>(vertexBuffer->vbih);
-    primitive->setBuffers(vbi, vertexBuffer, indexBuffer);
+    primitive->vertexBuffer = vertexBuffer;
+    primitive->indexBuffer = indexBuffer;
     primitive->type = pt;
 }
 

filament/backend/src/metal/MetalHandles.h

@@ -194,12 +194,8 @@ struct MetalIndexBuffer : public HwIndexBuffer {
 };
 
 struct MetalRenderPrimitive : public HwRenderPrimitive {
-    MetalRenderPrimitive();
-    void setBuffers(MetalVertexBufferInfo const* const vbi,
-            MetalVertexBuffer* vertexBuffer, MetalIndexBuffer* indexBuffer);
     // The pointers to MetalVertexBuffer and MetalIndexBuffer are "weak".
     // The MetalVertexBuffer and MetalIndexBuffer must outlive the MetalRenderPrimitive.
-
     MetalVertexBuffer* vertexBuffer = nullptr;
     MetalIndexBuffer* indexBuffer = nullptr;
 };
@@ -380,7 +376,6 @@ public:
 
     math::uint2 getAttachmentSize() noexcept;
 
-    bool isDefaultRenderTarget() const { return defaultRenderTarget; }
     uint8_t getSamples() const { return samples; }
 
     Attachment getDrawColorAttachment(size_t index);

filament/backend/src/metal/MetalHandles.mm

@@ -536,15 +536,6 @@ MetalIndexBuffer::MetalIndexBuffer(MetalContext& context, BufferUsage usage, uin
         uint32_t indexCount) : HwIndexBuffer(elementSize, indexCount),
         buffer(context, BufferObjectBinding::VERTEX, usage, elementSize * indexCount, true) { }
 
-MetalRenderPrimitive::MetalRenderPrimitive() {
-}
-
-void MetalRenderPrimitive::setBuffers(MetalVertexBufferInfo const* const vbi,
-        MetalVertexBuffer* vertexBuffer, MetalIndexBuffer* indexBuffer) {
-    this->vertexBuffer = vertexBuffer;
-    this->indexBuffer = indexBuffer;
-}
-
 MetalProgram::MetalProgram(MetalContext& context, Program&& program) noexcept
     : HwProgram(program.getName()), mContext(context) {
     mToken = context.shaderCompiler->createProgram(program.getName(), std::move(program));

filament/backend/src/opengl/GLUtils.cpp

@@ -16,9 +16,15 @@
 
 #include "GLUtils.h"
 
+#include "private/backend/Driver.h"
+
+#include <utils/compiler.h>
+#include <utils/ostream.h>
 #include <utils/trap.h>
 
-#include "private/backend/Driver.h"
+#include <string_view>
+
+#include <stddef.h>
 
 namespace filament::backend {
 
@@ -28,38 +34,31 @@ using namespace utils;
 namespace GLUtils {
 
 UTILS_NOINLINE
-const char* getGLError(GLenum error) noexcept {
-    const char* string = "unknown";
+std::string_view getGLErrorString(GLenum error) noexcept {
     switch (error) {
         case GL_NO_ERROR:
-            string = "GL_NO_ERROR";
-            break;
+            return "GL_NO_ERROR";
         case GL_INVALID_ENUM:
-            string = "GL_INVALID_ENUM";
-            break;
+            return "GL_INVALID_ENUM";
         case GL_INVALID_VALUE:
-            string = "GL_INVALID_VALUE";
-            break;
+            return "GL_INVALID_VALUE";
         case GL_INVALID_OPERATION:
-            string = "GL_INVALID_OPERATION";
-            break;
+            return "GL_INVALID_OPERATION";
         case GL_INVALID_FRAMEBUFFER_OPERATION:
-            string = "GL_INVALID_FRAMEBUFFER_OPERATION";
-            break;
+            return "GL_INVALID_FRAMEBUFFER_OPERATION";
         case GL_OUT_OF_MEMORY:
-            string = "GL_OUT_OF_MEMORY";
-            break;
+            return "GL_OUT_OF_MEMORY";
         default:
             break;
     }
-    return string;
+    return "unknown";
 }
 
 UTILS_NOINLINE
 GLenum checkGLError(io::ostream& out, const char* function, size_t line) noexcept {
     GLenum const error = glGetError();
-    if (error != GL_NO_ERROR) {
-        const char* string = getGLError(error);
+    if (UTILS_VERY_UNLIKELY(error != GL_NO_ERROR)) {
+        auto const string = getGLErrorString(error);
         out << "OpenGL error " << io::hex << error << " (" << string << ") in \""
             << function << "\" at line " << io::dec << line << io::endl;
     }
@@ -69,46 +68,39 @@ GLenum checkGLError(io::ostream& out, const char* function, size_t line) noexcep
 UTILS_NOINLINE
 void assertGLError(io::ostream& out, const char* function, size_t line) noexcept {
     GLenum const err = checkGLError(out, function, line);
-    if (err != GL_NO_ERROR) {
+    if (UTILS_VERY_UNLIKELY(err != GL_NO_ERROR)) {
         debug_trap();
     }
 }
 
 UTILS_NOINLINE
-const char* getFramebufferStatus(GLenum status) noexcept {
-    const char* string = "unknown";
+std::string_view getFramebufferStatusString(GLenum status) noexcept {
     switch (status) {
         case GL_FRAMEBUFFER_COMPLETE:
-            string = "GL_FRAMEBUFFER_COMPLETE";
-            break;
+            return "GL_FRAMEBUFFER_COMPLETE";
         case GL_FRAMEBUFFER_INCOMPLETE_ATTACHMENT:
-            string = "GL_FRAMEBUFFER_INCOMPLETE_ATTACHMENT";
-            break;
+            return "GL_FRAMEBUFFER_INCOMPLETE_ATTACHMENT";
         case GL_FRAMEBUFFER_INCOMPLETE_MISSING_ATTACHMENT:
-            string = "GL_FRAMEBUFFER_INCOMPLETE_MISSING_ATTACHMENT";
-            break;
+            return "GL_FRAMEBUFFER_INCOMPLETE_MISSING_ATTACHMENT";
         case GL_FRAMEBUFFER_UNSUPPORTED:
-            string = "GL_FRAMEBUFFER_UNSUPPORTED";
-            break;
+            return "GL_FRAMEBUFFER_UNSUPPORTED";
 #ifndef FILAMENT_SILENCE_NOT_SUPPORTED_BY_ES2
         case GL_FRAMEBUFFER_UNDEFINED:
-            string = "GL_FRAMEBUFFER_UNDEFINED";
-            break;
+            return "GL_FRAMEBUFFER_UNDEFINED";
         case GL_FRAMEBUFFER_INCOMPLETE_MULTISAMPLE:
-            string = "GL_FRAMEBUFFER_INCOMPLETE_MULTISAMPLE";
-            break;
+            return "GL_FRAMEBUFFER_INCOMPLETE_MULTISAMPLE";
 #endif
         default:
             break;
     }
-    return string;
+    return "unknown";
 }
 
 UTILS_NOINLINE
 GLenum checkFramebufferStatus(io::ostream& out, GLenum target, const char* function, size_t line) noexcept {
     GLenum const status = glCheckFramebufferStatus(target);
-    if (status != GL_FRAMEBUFFER_COMPLETE) {
-        const char* string = getFramebufferStatus(status);
+    if (UTILS_VERY_UNLIKELY(status != GL_FRAMEBUFFER_COMPLETE)) {
+        auto const string = getFramebufferStatusString(status);
         out << "OpenGL framebuffer error " << io::hex << status << " (" << string << ") in \""
             << function << "\" at line " << io::dec << line << io::endl;
     }
@@ -118,7 +110,7 @@ GLenum checkFramebufferStatus(io::ostream& out, GLenum target, const char* funct
 UTILS_NOINLINE
 void assertFramebufferStatus(io::ostream& out, GLenum target, const char* function, size_t line) noexcept {
     GLenum const status = checkFramebufferStatus(out, target, function, line);
-    if (status != GL_FRAMEBUFFER_COMPLETE) {
+    if (UTILS_VERY_UNLIKELY(status != GL_FRAMEBUFFER_COMPLETE)) {
         debug_trap();
     }
 }

filament/backend/src/opengl/GLUtils.h

@@ -17,29 +17,26 @@
 #ifndef TNT_FILAMENT_BACKEND_OPENGL_GLUTILS_H
 #define TNT_FILAMENT_BACKEND_OPENGL_GLUTILS_H
 
-#include <utils/compiler.h>
 #include <utils/debug.h>
-#include <utils/Log.h>
+#include <utils/ostream.h>
 
 #include <backend/DriverEnums.h>
 
 #include <string_view>
 #include <unordered_set>
 
-#include <stdint.h>
 #include <stddef.h>
-#include <string.h>
+#include <stdint.h>
 
 #include "gl_headers.h"
 
-namespace filament::backend {
-namespace GLUtils {
+namespace filament::backend::GLUtils {
 
-const char* getGLError(GLenum error) noexcept;
+std::string_view getGLErrorString(GLenum error) noexcept;
 GLenum checkGLError(utils::io::ostream& out, const char* function, size_t line) noexcept;
 void assertGLError(utils::io::ostream& out, const char* function, size_t line) noexcept;
 
-const char* getFramebufferStatus(GLenum err) noexcept;
+std::string_view getFramebufferStatusString(GLenum err) noexcept;
 GLenum checkFramebufferStatus(utils::io::ostream& out, GLenum target, const char* function, size_t line) noexcept;
 void assertFramebufferStatus(utils::io::ostream& out, GLenum target, const char* function, size_t line) noexcept;
 
@@ -53,7 +50,7 @@ void assertFramebufferStatus(utils::io::ostream& out, GLenum target, const char*
 #   define CHECK_GL_FRAMEBUFFER_STATUS(out, target) { GLUtils::checkFramebufferStatus(out, target, __func__, __LINE__); }
 #endif
 
-constexpr GLuint getComponentCount(ElementType type) noexcept {
+constexpr GLuint getComponentCount(ElementType const type) noexcept {
     using ElementType = ElementType;
     switch (type) {
         case ElementType::BYTE:
@@ -87,27 +84,29 @@ constexpr GLuint getComponentCount(ElementType type) noexcept {
         case ElementType::USHORT4:
             return 4;
     }
+    // should never happen
+    return 1;
 }
 
 // ------------------------------------------------------------------------------------------------
 // Our enums to GLenum conversions
 // ------------------------------------------------------------------------------------------------
 
-constexpr GLbitfield getAttachmentBitfield(TargetBufferFlags flags) noexcept {
+constexpr GLbitfield getAttachmentBitfield(TargetBufferFlags const flags) noexcept {
     GLbitfield mask = 0;
     if (any(flags & TargetBufferFlags::COLOR_ALL)) {
-        mask |= (GLbitfield)GL_COLOR_BUFFER_BIT;
+        mask |= GLbitfield(GL_COLOR_BUFFER_BIT);
     }
     if (any(flags & TargetBufferFlags::DEPTH)) {
-        mask |= (GLbitfield)GL_DEPTH_BUFFER_BIT;
+        mask |= GLbitfield(GL_DEPTH_BUFFER_BIT);
     }
     if (any(flags & TargetBufferFlags::STENCIL)) {
-        mask |= (GLbitfield)GL_STENCIL_BUFFER_BIT;
+        mask |= GLbitfield(GL_STENCIL_BUFFER_BIT);
     }
     return mask;
 }
 
-constexpr GLenum getBufferUsage(BufferUsage usage) noexcept {
+constexpr GLenum getBufferUsage(BufferUsage const usage) noexcept {
     switch (usage) {
         case BufferUsage::STATIC:
             return GL_STATIC_DRAW;
@@ -116,7 +115,7 @@ constexpr GLenum getBufferUsage(BufferUsage usage) noexcept {
     }
 }
 
-constexpr GLenum getBufferBindingType(BufferObjectBinding bindingType) noexcept {
+constexpr GLenum getBufferBindingType(BufferObjectBinding const bindingType) noexcept {
     switch (bindingType) {
         case BufferObjectBinding::VERTEX:
             return GL_ARRAY_BUFFER;
@@ -135,13 +134,15 @@ constexpr GLenum getBufferBindingType(BufferObjectBinding bindingType) noexcept
             return 0x90D2; // just to return something
 #endif
     }
+    // should never happen
+    return GL_ARRAY_BUFFER;
 }
 
-constexpr GLboolean getNormalization(bool normalized) noexcept {
+constexpr GLboolean getNormalization(bool const normalized) noexcept {
     return GLboolean(normalized ? GL_TRUE : GL_FALSE);
 }
 
-constexpr GLenum getComponentType(ElementType type) noexcept {
+constexpr GLenum getComponentType(ElementType const type) noexcept {
     using ElementType = ElementType;
     switch (type) {
         case ElementType::BYTE:
@@ -184,9 +185,11 @@ constexpr GLenum getComponentType(ElementType type) noexcept {
             return GL_HALF_FLOAT_OES;
 #endif
     }
+    // should never happen
+    return GL_INT;
 }
 
-constexpr GLenum getTextureTargetNotExternal(SamplerType target) noexcept {
+constexpr GLenum getTextureTargetNotExternal(SamplerType const target) noexcept {
     switch (target) {
         case SamplerType::SAMPLER_2D:
             return GL_TEXTURE_2D;
@@ -202,14 +205,16 @@ constexpr GLenum getTextureTargetNotExternal(SamplerType target) noexcept {
             // we should never be here
             return GL_TEXTURE_2D;
     }
+    // should never happen
+    return GL_TEXTURE_2D;
 }
 
-constexpr GLenum getCubemapTarget(uint16_t layer) noexcept {
+constexpr GLenum getCubemapTarget(uint16_t const layer) noexcept {
     assert_invariant(layer <= 5);
     return GL_TEXTURE_CUBE_MAP_POSITIVE_X + layer;
 }
 
-constexpr GLenum getWrapMode(SamplerWrapMode mode) noexcept {
+constexpr GLenum getWrapMode(SamplerWrapMode const mode) noexcept {
     using SamplerWrapMode = SamplerWrapMode;
     switch (mode) {
         case SamplerWrapMode::REPEAT:
@@ -219,6 +224,8 @@ constexpr GLenum getWrapMode(SamplerWrapMode mode) noexcept {
         case SamplerWrapMode::MIRRORED_REPEAT:
             return GL_MIRRORED_REPEAT;
     }
+    // should never happen
+    return GL_CLAMP_TO_EDGE;
 }
 
 constexpr GLenum getTextureFilter(SamplerMinFilter filter) noexcept {
@@ -234,6 +241,8 @@ constexpr GLenum getTextureFilter(SamplerMinFilter filter) noexcept {
             return GL_NEAREST_MIPMAP_NEAREST
                    - GLenum(SamplerMinFilter::NEAREST_MIPMAP_NEAREST) + GLenum(filter);
     }
+    // should never happen
+    return GL_NEAREST;
 }
 
 constexpr GLenum getTextureFilter(SamplerMagFilter filter) noexcept {
@@ -241,7 +250,7 @@ constexpr GLenum getTextureFilter(SamplerMagFilter filter) noexcept {
 }
 
 
-constexpr GLenum getBlendEquationMode(BlendEquation mode) noexcept {
+constexpr GLenum getBlendEquationMode(BlendEquation const mode) noexcept {
     using BlendEquation = BlendEquation;
     switch (mode) {
         case BlendEquation::ADD:               return GL_FUNC_ADD;
@@ -250,9 +259,11 @@ constexpr GLenum getBlendEquationMode(BlendEquation mode) noexcept {
         case BlendEquation::MIN:               return GL_MIN;
         case BlendEquation::MAX:               return GL_MAX;
     }
+    // should never happen
+    return GL_FUNC_ADD;
 }
 
-constexpr GLenum getBlendFunctionMode(BlendFunction mode) noexcept {
+constexpr GLenum getBlendFunctionMode(BlendFunction const mode) noexcept {
     using BlendFunction = BlendFunction;
     switch (mode) {
         case BlendFunction::ZERO:                  return GL_ZERO;
@@ -267,9 +278,11 @@ constexpr GLenum getBlendFunctionMode(BlendFunction mode) noexcept {
         case BlendFunction::ONE_MINUS_DST_ALPHA:   return GL_ONE_MINUS_DST_ALPHA;
         case BlendFunction::SRC_ALPHA_SATURATE:    return GL_SRC_ALPHA_SATURATE;
     }
+    // should never happen
+    return GL_ONE;
 }
 
-constexpr GLenum getCompareFunc(SamplerCompareFunc func) noexcept {
+constexpr GLenum getCompareFunc(SamplerCompareFunc const func) noexcept {
     switch (func) {
         case SamplerCompareFunc::LE:    return GL_LEQUAL;
         case SamplerCompareFunc::GE:    return GL_GEQUAL;
@@ -280,28 +293,30 @@ constexpr GLenum getCompareFunc(SamplerCompareFunc func) noexcept {
         case SamplerCompareFunc::A:     return GL_ALWAYS;
         case SamplerCompareFunc::N:     return GL_NEVER;
     }
+    // should never happen
+    return GL_LEQUAL;
 }
 
 #ifndef FILAMENT_SILENCE_NOT_SUPPORTED_BY_ES2
-constexpr GLenum getTextureCompareMode(SamplerCompareMode mode) noexcept {
+constexpr GLenum getTextureCompareMode(SamplerCompareMode const mode) noexcept {
     return mode == SamplerCompareMode::NONE ?
            GL_NONE : GL_COMPARE_REF_TO_TEXTURE;
 }
 
-constexpr GLenum getTextureCompareFunc(SamplerCompareFunc func) noexcept {
+constexpr GLenum getTextureCompareFunc(SamplerCompareFunc const func) noexcept {
     return getCompareFunc(func);
 }
 #endif
 
-constexpr GLenum getDepthFunc(SamplerCompareFunc func) noexcept {
+constexpr GLenum getDepthFunc(SamplerCompareFunc const func) noexcept {
     return getCompareFunc(func);
 }
 
-constexpr GLenum getStencilFunc(SamplerCompareFunc func) noexcept {
+constexpr GLenum getStencilFunc(SamplerCompareFunc const func) noexcept {
     return getCompareFunc(func);
 }
 
-constexpr GLenum getStencilOp(StencilOperation op) noexcept {
+constexpr GLenum getStencilOp(StencilOperation const op) noexcept {
     switch (op) {
         case StencilOperation::KEEP:        return GL_KEEP;
         case StencilOperation::ZERO:        return GL_ZERO;
@@ -312,9 +327,11 @@ constexpr GLenum getStencilOp(StencilOperation op) noexcept {
         case StencilOperation::DECR_WRAP:   return GL_DECR_WRAP;
         case StencilOperation::INVERT:      return GL_INVERT;
     }
+    // should never happen
+    return GL_KEEP;
 }
 
-constexpr GLenum getFormat(PixelDataFormat format) noexcept {
+constexpr GLenum getFormat(PixelDataFormat const format) noexcept {
     using PixelDataFormat = PixelDataFormat;
     switch (format) {
         case PixelDataFormat::RGB:              return GL_RGB;
@@ -336,9 +353,11 @@ constexpr GLenum getFormat(PixelDataFormat format) noexcept {
         default: return GL_NONE;
 #endif
     }
+    // should never happen
+    return GL_RGBA;
 }
 
-constexpr GLenum getType(PixelDataType type) noexcept {
+constexpr GLenum getType(PixelDataType const type) noexcept {
     using PixelDataType = PixelDataType;
     switch (type) {
         case PixelDataType::UBYTE:                return GL_UNSIGNED_BYTE;
@@ -360,10 +379,12 @@ constexpr GLenum getType(PixelDataType type) noexcept {
         default: return GL_NONE;
 #endif
     }
+    // should never happen
+    return GL_UNSIGNED_INT;
 }
 
 #if !defined(__EMSCRIPTEN__)  && !defined(FILAMENT_SILENCE_NOT_SUPPORTED_BY_ES2)
-constexpr GLenum getSwizzleChannel(TextureSwizzle c) noexcept {
+constexpr GLenum getSwizzleChannel(TextureSwizzle const c) noexcept {
     using TextureSwizzle = TextureSwizzle;
     switch (c) {
         case TextureSwizzle::SUBSTITUTE_ZERO:   return GL_ZERO;
@@ -373,10 +394,12 @@ constexpr GLenum getSwizzleChannel(TextureSwizzle c) noexcept {
         case TextureSwizzle::CHANNEL_2:         return GL_BLUE;
         case TextureSwizzle::CHANNEL_3:         return GL_ALPHA;
     }
+    // should never happen
+    return GL_RED;
 }
 #endif
 
-constexpr GLenum getCullingMode(CullingMode mode) noexcept {
+constexpr GLenum getCullingMode(CullingMode const mode) noexcept {
     switch (mode) {
         case CullingMode::NONE:
             // should never happen
@@ -388,11 +411,13 @@ constexpr GLenum getCullingMode(CullingMode mode) noexcept {
         case CullingMode::FRONT_AND_BACK:
             return GL_FRONT_AND_BACK;
     }
+    // should never happen
+    return GL_FRONT_AND_BACK;
 }
 
 // ES2 supported internal formats for texturing and how they  map to a format/type
 constexpr std::pair<GLenum, GLenum> textureFormatToFormatAndType(
-        TextureFormat format) noexcept {
+        TextureFormat const format) noexcept {
     switch (format) {
         case TextureFormat::R8:         return { 0x1909 /*GL_LUMINANCE*/, GL_UNSIGNED_BYTE };
         case TextureFormat::RGB8:       return { GL_RGB,                  GL_UNSIGNED_BYTE };
@@ -413,7 +438,7 @@ constexpr std::pair<GLenum, GLenum> textureFormatToFormatAndType(
 // clang loses it on this one, and generates a huge jump table when
 // inlined. So we don't  mark it as inline (only constexpr) which solves the problem,
 // strangely, when not inlined, clang simply generates an array lookup.
-constexpr /* inline */ GLenum getInternalFormat(TextureFormat format) noexcept {
+constexpr /* inline */ GLenum getInternalFormat(TextureFormat const format) noexcept {
     switch (format) {
 
         /* Formats supported by our ES2 implementations */
@@ -661,7 +686,7 @@ public:
 
 unordered_string_set split(const char* extensions) noexcept;
 
-} // namespace GLUtils
-} // namespace filament::backend
+} // namespace filament::backend::GLUtils
+
 
 #endif // TNT_FILAMENT_BACKEND_OPENGL_GLUTILS_H

filament/backend/src/opengl/OpenGLContext.cpp

@@ -340,7 +340,7 @@ void OpenGLContext::setDefaultState() noexcept {
         GL_DITHER,
         GL_SAMPLE_ALPHA_TO_COVERAGE,
         GL_SAMPLE_COVERAGE,
-        GL_POLYGON_OFFSET_FILL,  
+        GL_POLYGON_OFFSET_FILL,
     };
 
     UTILS_NOUNROLL
@@ -600,6 +600,12 @@ void OpenGLContext::initBugs(Bugs* bugs, Extensions const& exts,
         // For Mozilla, the issue appears to be observed regardless of whether the renderer is
         // ANGLE or not. (b/376125497)
         bugs->rebind_buffer_after_deletion = true;
+
+        // We disable depth precache for the default material on Mozilla FireFox. It struggles with
+        // slow shader compile/link times if the shader contains large arrays of uniform. Some depth
+        // program variants have skinning-related data, which incurs this slowness and end up
+        // causing an initial startup stalls. (b/392917621)
+        bugs->disable_depth_precache_for_default_material = true;
     }
 
 #ifdef BACKEND_OPENGL_VERSION_GLES
@@ -1069,41 +1075,41 @@ void OpenGLContext::resetState() noexcept {
     glCullFace(state.raster.cullFace);
     glBlendEquationSeparate(state.raster.blendEquationRGB, state.raster.blendEquationA);
     glBlendFuncSeparate(
-        state.raster.blendFunctionSrcRGB, 
+        state.raster.blendFunctionSrcRGB,
         state.raster.blendFunctionDstRGB,
         state.raster.blendFunctionSrcA,
         state.raster.blendFunctionDstA
     );
     glColorMask(
-        state.raster.colorMask, 
-        state.raster.colorMask, 
-        state.raster.colorMask, 
+        state.raster.colorMask,
+        state.raster.colorMask,
+        state.raster.colorMask,
         state.raster.colorMask
     );
     glDepthMask(state.raster.depthMask);
     glDepthFunc(state.raster.depthFunc);
-    
+
     // state.stencil
     glStencilFuncSeparate(
-        GL_FRONT, 
-        state.stencil.front.func.func, 
-        state.stencil.front.func.ref, 
+        GL_FRONT,
+        state.stencil.front.func.func,
+        state.stencil.front.func.ref,
         state.stencil.front.func.mask
     );
     glStencilFuncSeparate(
-        GL_BACK, 
-        state.stencil.back.func.func, 
-        state.stencil.back.func.ref, 
+        GL_BACK,
+        state.stencil.back.func.func,
+        state.stencil.back.func.ref,
         state.stencil.back.func.mask
     );
     glStencilOpSeparate(
-        GL_FRONT, 
+        GL_FRONT,
         state.stencil.front.op.sfail,
         state.stencil.front.op.dpfail,
         state.stencil.front.op.dppass
     );
     glStencilOpSeparate(
-        GL_BACK, 
+        GL_BACK,
         state.stencil.back.op.sfail,
         state.stencil.back.op.dpfail,
         state.stencil.back.op.dppass
@@ -1206,9 +1212,9 @@ void OpenGLContext::resetState() noexcept {
 
     // state.window
     glScissor(
-        state.window.scissor.x, 
-        state.window.scissor.y, 
-        state.window.scissor.z, 
+        state.window.scissor.x,
+        state.window.scissor.y,
+        state.window.scissor.z,
         state.window.scissor.w
     );
     glViewport(

filament/backend/src/opengl/OpenGLContext.h

@@ -328,6 +328,11 @@ public:
         // bugs or performance issues.
         bool force_feature_level0;
 
+        // Some browsers, such as Firefox on Mac, struggle with slow shader compile/link times when
+        // creating programs for the default material, leading to startup stutters. This workaround
+        // prevents these stutters by not precaching depth variants of the default material for
+        // those particular browsers.
+        bool disable_depth_precache_for_default_material;
 
     } bugs = {};
 
@@ -569,6 +574,9 @@ private:
             {   bugs.force_feature_level0,
                     "force_feature_level0",
                     ""},
+            {   bugs.disable_depth_precache_for_default_material,
+                    "disable_depth_precache_for_default_material",
+                    ""},
     }};
 
     // this is chosen to minimize code size

filament/backend/src/opengl/OpenGLDriver.cpp

@@ -2098,6 +2098,7 @@ void OpenGLDriver::setAcquiredImage(Handle<HwStream> sh, void* hwbuffer, const m
 
     glstream->user_thread.pending = mPlatform.transformAcquiredImage({
             hwbuffer, cb, userData, handler });
+    glstream->user_thread.transform = transform;
 
     if (glstream->user_thread.pending.image != nullptr) {
         // If there's no pending image, do nothing. Note that GL_OES_EGL_image does not let you pass
@@ -2434,6 +2435,8 @@ bool OpenGLDriver::isWorkaroundNeeded(Workaround workaround) {
             return mContext.bugs.disable_blit_into_texture_array;
         case Workaround::POWER_VR_SHADER_WORKAROUNDS:
             return mContext.bugs.powervr_shader_workarounds;
+        case Workaround::DISABLE_DEPTH_PRECACHE_FOR_DEFAULT_MATERIAL:
+            return mContext.bugs.disable_depth_precache_for_default_material;
         default:
             return false;
     }

filament/backend/src/opengl/OpenGLProgram.cpp

@@ -85,6 +85,7 @@ OpenGLProgram::~OpenGLProgram() noexcept {
         delete lazyInitializationData;
 
         ShaderCompilerService::terminate(mToken);
+        assert_invariant(!mToken);
     }
 
     delete [] mUniformsRecords;

filament/backend/src/opengl/ShaderCompilerService.h

@@ -24,23 +24,23 @@
 #include "OpenGLBlobCache.h"
 
 #include <backend/CallbackHandler.h>
+#include <backend/DriverEnums.h>
 #include <backend/Program.h>
 
 #include <utils/CString.h>
 #include <utils/FixedCapacityVector.h>
-#include <utils/Invocable.h>
 #include <utils/JobSystem.h>
 
-#include <atomic>
-#include <condition_variable>
-#include <deque>
+#include <array>
 #include <functional>
 #include <memory>
 #include <mutex>
-#include <thread>
+#include <tuple>
 #include <utility>
 #include <vector>
 
+#include <stdint.h>
+
 namespace filament::backend {
 
 class OpenGLDriver;
@@ -57,6 +57,8 @@ class ShaderCompilerService {
 
 public:
     using program_token_t = std::shared_ptr<OpenGLProgramToken>;
+    using shaders_t = std::array<GLuint, Program::SHADER_TYPE_COUNT>;
+    using shaders_source_t = std::array<utils::CString, Program::SHADER_TYPE_COUNT>;
 
     explicit ShaderCompilerService(OpenGLDriver& driver);
 
@@ -82,6 +84,7 @@ public:
     void tick();
 
     // Destroys a valid token and all associated resources. Used to "cancel" a program compilation.
+    // This function is not called if `initialize(token)` is already invoked.
     static void terminate(program_token_t& token);
 
     // stores a user data pointer in the token
@@ -90,6 +93,12 @@ public:
     // retrieves the user data pointer stored in the token
     static void* getUserData(const program_token_t& token) noexcept;
 
+    // Issue one callback handle.
+    CallbackManager::Handle issueCallbackHandle() const noexcept;
+
+    // Return a callback handle to the callback manager.
+    void submitCallbackHandle(CallbackManager::Handle handle) noexcept;
+
     // call the callback when all active programs are ready
     void notifyWhenAllProgramsAreReady(
             CallbackHandler* handler, CallbackHandler::Callback callback, void* user);
@@ -97,7 +106,7 @@ public:
 private:
     struct Job {
         template<typename FUNC>
-        Job(FUNC&& fn) : fn(std::forward<FUNC>(fn)) {}
+        Job(FUNC&& fn) : fn(std::forward<FUNC>(fn)) {} // NOLINT(*-explicit-constructor)
         Job(std::function<bool(Job const& job)> fn,
                 CallbackHandler* handler, void* user, CallbackHandler::Callback callback)
                 : fn(std::move(fn)), handler(handler), user(user), callback(callback) {
@@ -126,39 +135,49 @@ private:
     using ContainerType = std::tuple<CompilerPriorityQueue, program_token_t, Job>;
     std::vector<ContainerType> mRunAtNextTickOps;
 
-    GLuint initialize(ShaderCompilerService::program_token_t& token) noexcept;
+    GLuint initialize(program_token_t& token);
+    void ensureTokenIsReady(program_token_t const& token);
 
-    static void getProgramFromCompilerPool(program_token_t& token) noexcept;
-
-    static void compileShaders(
-            OpenGLContext& context,
-            Program::ShaderSource shadersSource,
-            utils::FixedCapacityVector<Program::SpecializationConstant> const& specializationConstants,
-            bool multiview,
-            std::array<GLuint, Program::SHADER_TYPE_COUNT>& outShaders,
-            std::array<utils::CString, Program::SHADER_TYPE_COUNT>& outShaderSourceCode) noexcept;
-
-    static void process_GOOGLE_cpp_style_line_directive(OpenGLContext& context,
-            char* source, size_t len) noexcept;
-
-    static void process_OVR_multiview2(OpenGLContext& context, int32_t eyeCount,
-            char* source, size_t len) noexcept;
-
-    static std::string_view process_ARB_shading_language_packing(OpenGLContext& context) noexcept;
-
-    static std::array<std::string_view, 3> splitShaderSource(std::string_view source) noexcept;
-
-    static GLuint linkProgram(OpenGLContext& context,
-            std::array<GLuint, Program::SHADER_TYPE_COUNT> shaders,
-            utils::FixedCapacityVector<std::pair<utils::CString, uint8_t>> const& attributes) noexcept;
-
-    static bool checkProgramStatus(program_token_t const& token) noexcept;
-
-    void runAtNextTick(CompilerPriorityQueue priority,
-            const program_token_t& token, Job job) noexcept;
+    void runAtNextTick(CompilerPriorityQueue priority, program_token_t const& token,
+            Job job) noexcept;
     void executeTickOps() noexcept;
-    bool cancelTickOp(program_token_t token) noexcept;
-    // order of insertion is important
+    bool cancelTickOp(program_token_t const& token) noexcept;
+
+    // Compile shaders with the given `shaderSource`. `gl.shaders` is always populated with valid
+    // shader IDs after this method. But this doesn't necessarily mean the shaders are successfully
+    // compiled. Errors can be checked by calling `checkCompileStatus` later.
+    static void compileShaders(OpenGLContext& context, Program::ShaderSource shadersSource,
+            utils::FixedCapacityVector<Program::SpecializationConstant> const&
+                    specializationConstants,
+            bool multiview, program_token_t const& token) noexcept;
+
+    // Check if the shader compilation is completed. You may want to call this when the extension
+    // `KHR_parallel_shader_compile` is enabled.
+    static bool isCompileCompleted(program_token_t const& token) noexcept;
+
+    // Check compilation status of the shaders and log errors on failure.
+    static void checkCompileStatus(program_token_t const& token) noexcept;
+
+    // Create a program by linking the compiled shaders. `gl.program` is always populated with a
+    // valid program ID after this method. But this doesn't necessarily mean the program is
+    // successfully linked. Errors can be checked by calling `checkLinkStatusAndCleanupShaders`
+    // later.
+    static void linkProgram(OpenGLContext const& context, program_token_t const& token) noexcept;
+
+    // Check if the program link is completed. You may want to call this when the extension
+    // `KHR_parallel_shader_compile` is enabled.
+    static bool isLinkCompleted(program_token_t const& token) noexcept;
+
+    // Check link status of the program and log errors on failure. Return the result of the link.
+    // Also cleanup shaders regardless of the result.
+    static bool checkLinkStatusAndCleanupShaders(program_token_t const& token) noexcept;
+
+    // Try caching the program if we haven't done it yet. Cache it only when the program is valid.
+    static void tryCachingProgram(OpenGLBlobCache& cache, OpenGLPlatform& platform,
+            program_token_t const& token) noexcept;
+
+    // Cleanup GL resources.
+    static void cleanupProgramAndShaders(program_token_t const& token) noexcept;
 };
 
 } // namespace filament::backend

filament/backend/src/opengl/platforms/CocoaExternalImage.mm

@@ -17,9 +17,11 @@
 #define COREVIDEO_SILENCE_GL_DEPRECATION
 
 #include "CocoaExternalImage.h"
-#include <utils/Panic.h>
 #include "../GLUtils.h"
 
+#include <utils/Panic.h>
+#include <utils/Log.h>
+
 namespace filament::backend {
 
 static const char *s_vertex = R"SHADER(#version 410 core

filament/backend/src/opengl/platforms/CocoaTouchExternalImage.mm

@@ -28,6 +28,7 @@
 #include <utils/compiler.h>
 #include <utils/Panic.h>
 #include <utils/debug.h>
+#include <utils/Log.h>
 
 namespace filament::backend {
 

filament/backend/src/ostream.cpp

@@ -15,6 +15,7 @@
  */
 
 #include <backend/BufferDescriptor.h>
+#include <backend/BufferObjectStreamDescriptor.h>
 #include <backend/DescriptorSetOffsetArray.h>
 #include <backend/DriverEnums.h>
 #include <backend/PipelineState.h>
@@ -437,6 +438,10 @@ io::ostream& operator<<(io::ostream& out, BufferDescriptor const& b) {
     << ", user=" << b.getUser() << " }";
 }
 
+io::ostream& operator<<(io::ostream& out, const BufferObjectStreamDescriptor& b) {
+    return out << "BufferObjectStreamDescriptor{ streams(" << b.mStreams.size() << ")=... }";
+}
+
 io::ostream& operator<<(io::ostream& out, PixelBufferDescriptor const& b) {
     BufferDescriptor const& base = static_cast<BufferDescriptor const&>(b);
     return out << "PixelBufferDescriptor{ " << base

filament/backend/src/vulkan/VulkanBlitter.cpp

@@ -17,9 +17,6 @@
 #include "VulkanBlitter.h"
 #include "VulkanCommands.h"
 #include "VulkanContext.h"
-#include "VulkanFboCache.h"
-#include "VulkanHandles.h"
-#include "VulkanSamplerCache.h"
 #include "VulkanTexture.h"
 #include "vulkan/utils/Image.h"
 

filament/backend/src/vulkan/VulkanBlitter.h

@@ -24,13 +24,6 @@
 
 namespace filament::backend {
 
-class VulkanBuffer;
-class VulkanFboCache;
-class VulkanPipelineCache;
-class VulkanSamplerCache;
-
-struct VulkanProgram;
-
 class VulkanBlitter {
 public:
     VulkanBlitter(VkPhysicalDevice physicalDevice, VulkanCommands* commands) noexcept;

filament/backend/src/vulkan/VulkanCommands.cpp

@@ -295,6 +295,8 @@ VulkanCommandBuffer& CommandBufferPool::getRecording() {
 }
 
 void CommandBufferPool::gc() {
+    FVK_SYSTRACE_CONTEXT();
+    FVK_SYSTRACE_START("CommandBufferPool::gc");
     ActiveBuffers reclaimed;
     mSubmitted.forEachSetBit([this,&reclaimed] (size_t index) {
         auto& buffer = mBuffers[index];
@@ -304,6 +306,7 @@ void CommandBufferPool::gc() {
         }
     });
     mSubmitted &= ~reclaimed;
+    FVK_SYSTRACE_END();
 }
 
 void CommandBufferPool::update() {
@@ -333,7 +336,9 @@ void CommandBufferPool::wait() {
     mSubmitted.forEachSetBit([this, &count, &fences] (size_t index) {
         fences[count++] = mBuffers[index]->getVkFence();
     });
-    vkWaitForFences(mDevice, count, fences, VK_TRUE, UINT64_MAX);
+    if (count) {
+        vkWaitForFences(mDevice, count, fences, VK_TRUE, UINT64_MAX);
+    }
     update();
 }
 

filament/backend/src/vulkan/VulkanConstants.h

@@ -152,12 +152,12 @@ static_assert(FVK_ENABLED(FVK_DEBUG_VALIDATION));
 #elif FVK_ENABLED(FVK_DEBUG_SYSTRACE)
 
     #include <utils/Systrace.h>
-    
+
     #define FVK_SYSTRACE_CONTEXT()      SYSTRACE_CONTEXT()
     #define FVK_SYSTRACE_START(marker)  SYSTRACE_NAME_BEGIN(marker)
     #define FVK_SYSTRACE_END()          SYSTRACE_NAME_END()
-    #define FVK_SYSTRACE_SCOPE()        SYSTRACE_NAME(__func__)
-    #define FVK_PROFILE_MARKER(marker)  FVK_SYSTRACE_SCOPE()
+    #define FVK_SYSTRACE_SCOPE()        SYSTRACE_CALL()
+    #define FVK_PROFILE_MARKER(marker)  SYSTRACE_CALL()
 
 #else
     #define FVK_SYSTRACE_CONTEXT()

filament/backend/src/vulkan/VulkanContext.cpp

@@ -56,9 +56,9 @@ VkImageView VulkanAttachment::getImageView() {
     assert_invariant(texture);
     VkImageSubresourceRange range = getSubresourceRange();
     if (range.layerCount > 1) {
-        return texture->getMultiviewAttachmentView(range);
+        return texture->getAttachmentView(range, VK_IMAGE_VIEW_TYPE_2D_ARRAY);
     }
-    return texture->getAttachmentView(range);
+    return texture->getAttachmentView(range, VK_IMAGE_VIEW_TYPE_2D);
 }
 
 bool VulkanAttachment::isDepth() const {
@@ -68,11 +68,11 @@ bool VulkanAttachment::isDepth() const {
 VkImageSubresourceRange VulkanAttachment::getSubresourceRange() const {
     assert_invariant(texture);
     return {
-            .aspectMask = texture->getImageAspect(),
-            .baseMipLevel = uint32_t(level),
-            .levelCount = 1,
-            .baseArrayLayer = uint32_t(layer),
-            .layerCount = layerCount,
+        .aspectMask = texture->getImageAspect(),
+        .baseMipLevel = uint32_t(level),
+        .levelCount = 1,
+        .baseArrayLayer = uint32_t(layer),
+        .layerCount = layerCount,
     };
 }
 

filament/backend/src/vulkan/VulkanContext.h

@@ -17,7 +17,6 @@
 #ifndef TNT_FILAMENT_BACKEND_VULKANCONTEXT_H
 #define TNT_FILAMENT_BACKEND_VULKANCONTEXT_H
 
-#include "VulkanConstants.h"
 #include "vulkan/utils/Image.h"
 #include "vulkan/utils/Definitions.h"
 
@@ -30,8 +29,6 @@
 
 #include <bluevk/BlueVK.h>
 
-#include <memory>
-
 VK_DEFINE_HANDLE(VmaAllocator)
 VK_DEFINE_HANDLE(VmaPool)
 
@@ -73,13 +70,11 @@ struct VulkanRenderPass {
 // context are stored in VulkanPlatform.
 struct VulkanContext {
 public:
-    inline uint32_t selectMemoryType(uint32_t flags, VkFlags reqs) const {
-        if ((reqs & VK_MEMORY_PROPERTY_PROTECTED_BIT) != 0) {
-            assert_invariant(isProtectedMemorySupported() == true);
-        }
+    static uint32_t selectMemoryType(VkPhysicalDeviceMemoryProperties const& memoryProperties,
+            uint32_t flags, VkFlags reqs) {
         for (uint32_t i = 0; i < VK_MAX_MEMORY_TYPES; i++) {
             if (flags & 1) {
-                if ((mMemoryProperties.memoryTypes[i].propertyFlags & reqs) == reqs) {
+                if ((memoryProperties.memoryTypes[i].propertyFlags & reqs) == reqs) {
                     return i;
                 }
             }
@@ -88,6 +83,13 @@ public:
         return (uint32_t) VK_MAX_MEMORY_TYPES;
     }
 
+    inline uint32_t selectMemoryType(uint32_t flags, VkFlags reqs) const {
+        if ((reqs & VK_MEMORY_PROPERTY_PROTECTED_BIT) != 0) {
+            assert_invariant(isProtectedMemorySupported());
+        }
+        return selectMemoryType(mMemoryProperties, flags, reqs);
+    }
+
     inline fvkutils::VkFormatList const& getAttachmentDepthStencilFormats() const {
         return mDepthStencilFormats;
     }
@@ -121,7 +123,7 @@ public:
     }
 
     inline bool isMultiviewEnabled() const noexcept {
-        return mMultiviewEnabled;
+        return mPhysicalDeviceVk11Features.multiview == VK_TRUE;
     }
 
     inline bool isClipDistanceSupported() const noexcept {
@@ -145,6 +147,9 @@ private:
     VkPhysicalDeviceProperties2 mPhysicalDeviceProperties = {
         .sType = VK_STRUCTURE_TYPE_PHYSICAL_DEVICE_PROPERTIES_2,
     };
+    VkPhysicalDeviceVulkan11Features mPhysicalDeviceVk11Features = {
+        .sType = VK_STRUCTURE_TYPE_PHYSICAL_DEVICE_VULKAN_1_1_FEATURES,
+    };
     VkPhysicalDeviceFeatures2 mPhysicalDeviceFeatures = {
         .sType = VK_STRUCTURE_TYPE_PHYSICAL_DEVICE_FEATURES_2,
     };
@@ -157,7 +162,6 @@ private:
     };
     bool mDebugMarkersSupported = false;
     bool mDebugUtilsSupported = false;
-    bool mMultiviewEnabled = false;
     bool mLazilyAllocatedMemorySupported = false;
     bool mProtectedMemorySupported = false;
 

filament/backend/src/vulkan/VulkanDescriptorSetCache.cpp

@@ -31,8 +31,8 @@ namespace filament::backend {
 
 namespace {
 
-using DescriptorCount = VulkanDescriptorSetLayout::Count;
 using DescriptorSetLayoutArray = VulkanDescriptorSetCache::DescriptorSetLayoutArray;
+using DescriptorCount = VulkanDescriptorSetCache::DescriptorCount;
 
 // We create a pool for each layout as defined by the number of descriptors of each type. For
 // example, a layout of
@@ -203,11 +203,10 @@ public:
     DescriptorInfinitePool(VkDevice device)
         : mDevice(device) {}
 
-    VkDescriptorSet obtainSet(fvkmemory::resource_ptr<VulkanDescriptorSetLayout> layout) {
-        auto const vklayout = layout->getVkLayout();
+    VkDescriptorSet obtainSet(DescriptorCount const& count, VkDescriptorSetLayout vklayout) {
         DescriptorPool* sameTypePool = nullptr;
         for (auto& pool: mPools) {
-            if (!pool->canAllocate(layout->count)) {
+            if (!pool->canAllocate(count)) {
                 continue;
             }
             if (auto set = pool->obtainSet(vklayout); set != VK_NULL_HANDLE) {
@@ -225,8 +224,7 @@ public:
         }
 
         // We need to increase the set of pools by one.
-        mPools.push_back(std::make_unique<DescriptorPool>(mDevice,
-                DescriptorCount::fromLayoutBitmask(layout->bitmask), capacity));
+        mPools.push_back(std::make_unique<DescriptorPool>(mDevice, count, capacity));
         auto& pool = mPools.back();
         auto ret = pool->obtainSet(vklayout);
         assert_invariant(ret != VK_NULL_HANDLE && "failed to obtain a set?");
@@ -260,7 +258,6 @@ VulkanDescriptorSetCache::~VulkanDescriptorSetCache() = default;
 
 void VulkanDescriptorSetCache::terminate() noexcept{
     mDescriptorPool.reset();
-    clearHistory();
 }
 
 // bind() is not really binding the set but just stashing until we have all the info
@@ -277,32 +274,36 @@ void VulkanDescriptorSetCache::unbind(uint8_t setIndex) {
 }
 
 void VulkanDescriptorSetCache::commit(VulkanCommandBuffer* commands,
-        VkPipelineLayout pipelineLayout, fvkutils::DescriptorSetMask const& setMask) {
+        VkPipelineLayout pipelineLayout, fvkutils::DescriptorSetMask const& useExternalSamplers,
+        fvkutils::DescriptorSetMask const& setMask) {
     // setMask indicates the set of descriptor sets the driver wants to bind, curMask is the
     // actual set of sets that *needs* to be bound.
     fvkutils::DescriptorSetMask curMask = setMask;
 
-    auto& updateSets = mStashedSets;
-    auto& lastBoundSets = mLastBoundInfo.boundSets;
-
-    setMask.forEachSetBit([&](size_t index) {
-        if (!updateSets[index] || updateSets[index] == lastBoundSets[index]) {
+    auto const& updateSets = mStashedSets;
+    curMask.forEachSetBit([&](size_t index) {
+        if (!updateSets[index]) {
             curMask.unset(index);
         }
     });
 
-    if (curMask.none() &&
-            (mLastBoundInfo.pipelineLayout == pipelineLayout && mLastBoundInfo.setMask == setMask &&
-                    mLastBoundInfo.boundSets == updateSets)) {
-        return;
+    if (mLastBoundInfo.pipelineLayout == pipelineLayout) {
+        auto& lastBoundSets = mLastBoundInfo.boundSets;
+        curMask.forEachSetBit([&](size_t index) {
+            if (updateSets[index] == lastBoundSets[index] && !useExternalSamplers[index]) {
+                curMask.unset(index);
+            }
+        });
     }
 
-    curMask.forEachSetBit([&updateSets, commands, pipelineLayout](size_t index) {
+    curMask.forEachSetBit([&](size_t index) {
         // This code actually binds the descriptor sets.
         auto set = updateSets[index];
         VkCommandBuffer const cmdbuffer = commands->buffer();
+        VkDescriptorSet vkset = useExternalSamplers[index] ? set->getExternalSamplerVkSet() :
+            set->getVkSet();
         vkCmdBindDescriptorSets(cmdbuffer, VK_PIPELINE_BIND_POINT_GRAPHICS, pipelineLayout, index,
-                1, &set->vkSet, set->uniqueDynamicUboCount, set->getOffsets()->data());
+                1, &vkset, set->uniqueDynamicUboCount, set->getOffsets()->data());
         commands->acquire(set);
     });
 
@@ -328,48 +329,64 @@ void VulkanDescriptorSetCache::updateBuffer(fvkmemory::resource_ptr<VulkanDescri
     if (set->dynamicUboMask.test(binding)) {
         type = VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER_DYNAMIC;
     }
-    VkWriteDescriptorSet const descriptorWrite = {
+    VkWriteDescriptorSet descriptorWrite = {
         .sType = VK_STRUCTURE_TYPE_WRITE_DESCRIPTOR_SET,
-        .pNext = nullptr,
-        .dstSet = set->vkSet,
+        .dstSet = set->getVkSet(),
         .dstBinding = binding,
         .descriptorCount = 1,
         .descriptorType = type,
         .pBufferInfo = &info,
     };
     vkUpdateDescriptorSets(mDevice, 1, &descriptorWrite, 0, nullptr);
+
+    if (auto externalSamplerSet = set->getExternalSamplerVkSet();
+            externalSamplerSet != VK_NULL_HANDLE) {
+        descriptorWrite.dstSet = externalSamplerSet;
+        vkUpdateDescriptorSets(mDevice, 1, &descriptorWrite, 0, nullptr);
+    }
     set->acquire(bufferObject);
 }
 
-void VulkanDescriptorSetCache::updateSampler(fvkmemory::resource_ptr<VulkanDescriptorSet> set,
-        uint8_t binding, fvkmemory::resource_ptr<VulkanTexture> texture,
-        VkSampler sampler) noexcept {
-    VkDescriptorImageInfo info{
-        .sampler = sampler,
-    };
-    VkImageSubresourceRange const range = texture->getPrimaryViewRange();
+void VulkanDescriptorSetCache::updateSamplerImpl(VkDescriptorSet vkset, uint8_t binding,
+        fvkmemory::resource_ptr<VulkanTexture> texture, VkSampler sampler) noexcept {
+    VkImageSubresourceRange range = texture->getPrimaryViewRange();
     VkImageViewType const expectedType = texture->getViewType();
     if (any(texture->usage & TextureUsage::DEPTH_ATTACHMENT) &&
             expectedType == VK_IMAGE_VIEW_TYPE_2D) {
         // If the sampler is part of a mipmapped depth texture, where one of the level *can* be
-        // an attachment, then the sampler for this texture has the same view properties as a
-        // view for an attachment. Therefore, we can use getAttachmentView to get a
-        // corresponding VkImageView.
-        info.imageView = texture->getAttachmentView(range);
-    } else {
-        info.imageView = texture->getViewForType(range, expectedType);
+        // an attachment, then the range for this view has exactly one level and one layer.
+        range.levelCount = 1;
+        range.layerCount = 1;
     }
-    info.imageLayout = fvkutils::getVkLayout(texture->getDefaultLayout());
-    VkWriteDescriptorSet const descriptorWrite = {
+    VkDescriptorImageInfo info{
+        .sampler = sampler,
+        .imageView = texture->getView(range),
+        .imageLayout = fvkutils::getVkLayout(texture->getDefaultLayout()),
+    };
+
+    VkWriteDescriptorSet descriptorWrite = {
         .sType = VK_STRUCTURE_TYPE_WRITE_DESCRIPTOR_SET,
         .pNext = nullptr,
-        .dstSet = set->vkSet,
+        .dstSet = vkset,
         .dstBinding = binding,
         .descriptorCount = 1,
         .descriptorType = VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER,
         .pImageInfo = &info,
     };
     vkUpdateDescriptorSets(mDevice, 1, &descriptorWrite, 0, nullptr);
+}
+
+void VulkanDescriptorSetCache::updateSampler(fvkmemory::resource_ptr<VulkanDescriptorSet> set,
+        uint8_t binding, fvkmemory::resource_ptr<VulkanTexture> texture,
+        VkSampler sampler) noexcept {
+    updateSamplerImpl(set->getVkSet(), binding, texture, sampler);
+    set->acquire(texture);
+}
+
+void VulkanDescriptorSetCache::updateSamplerForExternalSamplerSet(
+        fvkmemory::resource_ptr<VulkanDescriptorSet> set, uint8_t binding,
+        fvkmemory::resource_ptr<VulkanTexture> texture) noexcept {
+    updateSamplerImpl(set->getExternalSamplerVkSet(), binding, texture, VK_NULL_HANDLE);
     set->acquire(texture);
 }
 
@@ -379,24 +396,34 @@ void VulkanDescriptorSetCache::updateInputAttachment(
     // TOOD: fill this in.
 }
 
+
 fvkmemory::resource_ptr<VulkanDescriptorSet> VulkanDescriptorSetCache::createSet(
         Handle<HwDescriptorSet> handle, fvkmemory::resource_ptr<VulkanDescriptorSetLayout> layout) {
-    auto const vkSet = mDescriptorPool->obtainSet(layout);
+    auto const vkSet = mDescriptorPool->obtainSet(layout->count, layout->getVkLayout());
     auto const& count = layout->count;
     auto const vklayout = layout->getVkLayout();
-    return fvkmemory::resource_ptr<VulkanDescriptorSet>::make(mResourceManager, handle, vkSet,
-            layout->bitmask.dynamicUbo, layout->count.dynamicUbo,
-            [vkSet, count, vklayout, this](VulkanDescriptorSet*) {
-                // Note that mDescriptorPool could be gone due to terminate (when the backend shuts
-                // down).
-                if (mDescriptorPool) {
-                    mDescriptorPool->recycle(count, vklayout, vkSet);
-                }
-            });
+    auto set = fvkmemory::resource_ptr<VulkanDescriptorSet>::make(
+            mResourceManager, handle, layout->bitmask.dynamicUbo, layout->count.dynamicUbo,
+            [vkSet, count, vklayout, this](
+                    VulkanDescriptorSet*) { this->manualRecycle(count, vklayout, vkSet); },
+            vkSet);
+    return set;
 }
 
-void VulkanDescriptorSetCache::clearHistory() {
-    mStashedSets = {};
+VkDescriptorSet VulkanDescriptorSetCache::getVkSet(DescriptorCount const& count,
+        VkDescriptorSetLayout vklayout) {
+    return mDescriptorPool->obtainSet(count, vklayout);
 }
 
+void VulkanDescriptorSetCache::manualRecycle(VulkanDescriptorSetLayout::Count const& count,
+        VkDescriptorSetLayout vklayout, VkDescriptorSet vkSet) {
+    // Note that mDescriptorPool could be gone due to terminate (when the backend shuts
+    // down).
+    if (mDescriptorPool) {
+        mDescriptorPool->recycle(count, vklayout, vkSet);
+    }
+}
+
+void VulkanDescriptorSetCache::gc() { mStashedSets = {}; }
+
 } // namespace filament::backend

filament/backend/src/vulkan/VulkanDescriptorSetCache.h

@@ -41,6 +41,9 @@ public:
             VulkanDescriptorSetLayout::UNIQUE_DESCRIPTOR_SET_COUNT;
 
     using DescriptorSetLayoutArray = VulkanDescriptorSetLayout::DescriptorSetLayoutArray;
+    using DescriptorSetArray =
+            std::array<fvkmemory::resource_ptr<VulkanDescriptorSet>, UNIQUE_DESCRIPTOR_SET_COUNT>;
+    using DescriptorCount = VulkanDescriptorSetLayout::Count;
 
     VulkanDescriptorSetCache(VkDevice device, fvkmemory::ResourceManager* resourceManager);
     ~VulkanDescriptorSetCache();
@@ -54,6 +57,10 @@ public:
     void updateSampler(fvkmemory::resource_ptr<VulkanDescriptorSet> set, uint8_t binding,
             fvkmemory::resource_ptr<VulkanTexture> texture, VkSampler sampler) noexcept;
 
+    void updateSamplerForExternalSamplerSet(fvkmemory::resource_ptr<VulkanDescriptorSet> set, uint8_t binding,
+            fvkmemory::resource_ptr<VulkanTexture> texture) noexcept;
+
+
     void updateInputAttachment(fvkmemory::resource_ptr<VulkanDescriptorSet> set,
             VulkanAttachment const& attachment) noexcept;
 
@@ -63,18 +70,28 @@ public:
     void unbind(uint8_t setIndex);
 
     void commit(VulkanCommandBuffer* commands, VkPipelineLayout pipelineLayout,
+            fvkutils::DescriptorSetMask const& useExternalSamplerMask,
             fvkutils::DescriptorSetMask const& setMask);
 
     fvkmemory::resource_ptr<VulkanDescriptorSet> createSet(Handle<HwDescriptorSet> handle,
             fvkmemory::resource_ptr<VulkanDescriptorSetLayout> layout);
 
-    void clearHistory();
+    // This method is meant to be used with external samplers
+    VkDescriptorSet getVkSet(DescriptorCount const& count, VkDescriptorSetLayout vklayout);
+
+    // This method is meant to be used with external samplers
+    void manualRecycle(VulkanDescriptorSetLayout::Count const& count, VkDescriptorSetLayout vklayout,
+            VkDescriptorSet vkSet);
+
+    DescriptorSetArray const& getBoundSets() const { return mStashedSets; }
+
+    void gc();
 
 private:
-    class DescriptorInfinitePool;
+    void updateSamplerImpl(VkDescriptorSet set, uint8_t binding,
+            fvkmemory::resource_ptr<VulkanTexture> texture, VkSampler sampler) noexcept;
 
-    using DescriptorSetArray =
-            std::array<fvkmemory::resource_ptr<VulkanDescriptorSet>, UNIQUE_DESCRIPTOR_SET_COUNT>;
+    class DescriptorInfinitePool;
 
     VkDevice mDevice;
     fvkmemory::ResourceManager* mResourceManager;

filament/backend/src/vulkan/VulkanDescriptorSetLayoutCache.cpp

@@ -18,6 +18,8 @@
 
 #include "VulkanHandles.h"
 
+#include <utils/Hash.h>
+
 namespace filament::backend {
 
 namespace {
@@ -58,6 +60,56 @@ uint32_t appendBindings(VkDescriptorSetLayoutBinding* toBind, VkDescriptorType t
     return count;
 }
 
+uint32_t appendSamplerBindings(VkDescriptorSetLayoutBinding* toBind,
+        fvkutils::SamplerBitmask const& mask, fvkutils::SamplerBitmask const& external,
+        utils::FixedCapacityVector<VkSampler> const& immutableSamplers) {
+    using Bitmask = fvkutils::SamplerBitmask;
+    uint32_t count = 0;
+    Bitmask alreadySeen;
+    uint8_t immutableIndex = 0;
+    size_t const immutableSamplerCount = immutableSamplers.size();
+    mask.forEachSetBit([&](size_t index) {
+        VkShaderStageFlags stages = 0;
+        uint32_t binding = 0;
+        if (index < fvkutils::getFragmentStageShift<Bitmask>()) {
+            binding = (uint32_t) index;
+            stages |= VK_SHADER_STAGE_VERTEX_BIT;
+            auto fragIndex = index + fvkutils::getFragmentStageShift<Bitmask>();
+            if (mask.test(fragIndex)) {
+                stages |= VK_SHADER_STAGE_FRAGMENT_BIT;
+                alreadySeen.set(fragIndex);
+            }
+        } else if (!alreadySeen.test(index)) {
+            // We are in fragment stage bits
+            binding = (uint32_t) (index - fvkutils::getFragmentStageShift<Bitmask>());
+            stages |= VK_SHADER_STAGE_FRAGMENT_BIT;
+        }
+
+        if (stages) {
+            toBind[count++] = {
+                .binding = binding,
+                .descriptorType = VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER,
+                .descriptorCount = 1,
+                .stageFlags = stages,
+                .pImmutableSamplers = external[index] && immutableSamplerCount > immutableIndex
+                                              ? &immutableSamplers[immutableIndex++]
+                                              : nullptr,
+            };
+        }
+    });
+    return count;
+}
+
+uint64_t computeImmutableSamplerHash(utils::FixedCapacityVector<VkSampler> const& samplers) {
+    size_t const size = samplers.size();
+    if (size == 0) {
+        return 0;
+    } else if (size == 1) {
+        return (uint64_t) samplers[0];
+    }
+    return utils::hash::murmur3((uint32_t*) samplers.data(), samplers.size() * 2, 0);
+}
+
 } // anonymous namespace
 
 VulkanDescriptorSetLayoutCache::VulkanDescriptorSetLayoutCache(VkDevice device,
@@ -73,37 +125,45 @@ void VulkanDescriptorSetLayoutCache::terminate() noexcept {
     }
 }
 
+VkDescriptorSetLayout VulkanDescriptorSetLayoutCache::getVkLayout(
+        VulkanDescriptorSetLayout::Bitmask const& bitmasks,
+        fvkutils::SamplerBitmask externalSamplers,
+        utils::FixedCapacityVector<VkSampler> immutableSamplers) {
+    LayoutKey key = {
+        .bitmask = bitmasks,
+        .immutableSamplerHash = computeImmutableSamplerHash(immutableSamplers),
+    };
+    if (auto itr = mVkLayouts.find(key); itr != mVkLayouts.end()) {
+        return itr->second;
+    }
+
+    VkDescriptorSetLayoutBinding toBind[VulkanDescriptorSetLayout::MAX_BINDINGS];
+    uint32_t count = 0;
+    count += appendBindings(&toBind[count], VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER_DYNAMIC,
+            bitmasks.dynamicUbo);
+    count += appendBindings(&toBind[count], VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER, bitmasks.ubo);
+    count += appendSamplerBindings(&toBind[count], bitmasks.sampler, externalSamplers,
+            immutableSamplers);
+    count += appendBindings(&toBind[count], VK_DESCRIPTOR_TYPE_INPUT_ATTACHMENT,
+            bitmasks.inputAttachment);
+
+    assert_invariant(count != 0 && "Need at least one binding for descriptor set layout.");
+    VkDescriptorSetLayoutCreateInfo dlinfo = {
+        .sType = VK_STRUCTURE_TYPE_DESCRIPTOR_SET_LAYOUT_CREATE_INFO,
+        .bindingCount = count,
+        .pBindings = toBind,
+    };
+    VkDescriptorSetLayout vklayout;
+    vkCreateDescriptorSetLayout(mDevice, &dlinfo, VKALLOC, &vklayout);
+    mVkLayouts[key] = vklayout;
+    return vklayout;
+}
+
 fvkmemory::resource_ptr<VulkanDescriptorSetLayout> VulkanDescriptorSetLayoutCache::createLayout(
         Handle<HwDescriptorSetLayout> handle, backend::DescriptorSetLayout&& info) {
+    BitmaskGroup maskGroup = VulkanDescriptorSetLayout::Bitmask::fromLayoutDescription(info);
     auto layout = fvkmemory::resource_ptr<VulkanDescriptorSetLayout>::make(mResourceManager, handle,
-            info);
-    VkDescriptorSetLayout vklayout = VK_NULL_HANDLE;
-    auto const& bitmasks = layout->bitmask;
-    if (auto itr = mVkLayouts.find(bitmasks); itr != mVkLayouts.end()) {
-        vklayout = itr->second;
-    } else {
-        VkDescriptorSetLayoutBinding toBind[VulkanDescriptorSetLayout::MAX_BINDINGS];
-        uint32_t count = 0;
-        count += appendBindings(&toBind[count], VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER_DYNAMIC,
-                bitmasks.dynamicUbo);
-        count += appendBindings(&toBind[count], VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER, bitmasks.ubo);
-        count += appendBindings(&toBind[count], VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER,
-                bitmasks.sampler);
-        count += appendBindings(&toBind[count], VK_DESCRIPTOR_TYPE_INPUT_ATTACHMENT,
-                bitmasks.inputAttachment);
-
-        assert_invariant(count != 0 && "Need at least one binding for descriptor set layout.");
-        VkDescriptorSetLayoutCreateInfo dlinfo = {
-            .sType = VK_STRUCTURE_TYPE_DESCRIPTOR_SET_LAYOUT_CREATE_INFO,
-            .pNext = nullptr,
-            .bindingCount = count,
-            .pBindings = toBind,
-        };
-
-        vkCreateDescriptorSetLayout(mDevice, &dlinfo, VKALLOC, &vklayout);
-        mVkLayouts[bitmasks] = vklayout;
-    }
-    layout->setVkLayout(vklayout);
+            std::move(info), getVkLayout(maskGroup, maskGroup.externalSampler));
     return layout;
 }
 

filament/backend/src/vulkan/VulkanDescriptorSetLayoutCache.h

@@ -26,12 +26,11 @@
 #include <backend/TargetBufferInfo.h>
 
 #include <utils/bitset.h>
+#include <utils/FixedCapacityVector.h>
 
 #include <bluevk/BlueVK.h>
 #include <tsl/robin_map.h>
 
-#include <memory>
-
 namespace filament::backend {
 
 class VulkanDescriptorSetLayoutCache {
@@ -41,21 +40,35 @@ public:
 
     void terminate() noexcept;
 
+    // Just a wrapper around getVkLayout()
     fvkmemory::resource_ptr<VulkanDescriptorSetLayout> createLayout(
             Handle<HwDescriptorSetLayout> handle, backend::DescriptorSetLayout&& info);
 
+    // This method is meant to be used with external samplers
+    VkDescriptorSetLayout getVkLayout(VulkanDescriptorSetLayout::Bitmask const& bitmasks,
+            fvkutils::SamplerBitmask externalSamplers,
+            utils::FixedCapacityVector<VkSampler> immutableSamplers = {});
+
 private:
     VkDevice mDevice;
     fvkmemory::ResourceManager* mResourceManager;
 
-    using BitmaskGroup = VulkanDescriptorSetLayout::Bitmask;
-    using BitmaskGroupHashFn = utils::hash::MurmurHashFn<BitmaskGroup>;
-    struct BitmaskGroupEqual {
-        bool operator()(BitmaskGroup const& k1, BitmaskGroup const& k2) const { return k1 == k2; }
+    struct LayoutKey {
+        // this describes the layout using bitset.
+        VulkanDescriptorSetLayout::Bitmask bitmask = {};
+        // number of immutable samplers can be arbitrary; so we hash them into 64-bit.
+        uint64_t immutableSamplerHash = 0;
+    };
+    static_assert(sizeof(LayoutKey) == 48);
+
+    using LayoutKeyHashFn = utils::hash::MurmurHashFn<LayoutKey>;
+    struct LayoutKeyEqual {
+        bool operator()(LayoutKey const& k1, LayoutKey const& k2) const {
+            return k1.bitmask == k2.bitmask && k1.immutableSamplerHash == k2.immutableSamplerHash;
+        }
     };
 
-    tsl::robin_map<BitmaskGroup, VkDescriptorSetLayout, BitmaskGroupHashFn, BitmaskGroupEqual>
-            mVkLayouts;
+    tsl::robin_map<LayoutKey, VkDescriptorSetLayout, LayoutKeyHashFn, LayoutKeyEqual> mVkLayouts;
 };
 
 } // namespace filament::backend

filament/backend/src/vulkan/VulkanDriver.cpp

@@ -25,6 +25,7 @@
 #include "VulkanHandles.h"
 #include "VulkanMemory.h"
 #include "VulkanTexture.h"
+#include "vulkan/VulkanSamplerCache.h"
 #include "vulkan/memory/ResourceManager.h"
 #include "vulkan/memory/ResourcePointer.h"
 #include "vulkan/utils/Conversion.h"
@@ -196,11 +197,9 @@ Dispatcher VulkanDriver::getDispatcher() const noexcept {
 }
 
 VulkanDriver::VulkanDriver(VulkanPlatform* platform, VulkanContext const& context,
-        Platform::DriverConfig const& driverConfig) noexcept
+        Platform::DriverConfig const& driverConfig)
     : mPlatform(platform),
-      mResourceManager(
-              driverConfig.handleArenaSize,
-              driverConfig.disableHandleUseAfterFreeCheck,
+      mResourceManager(driverConfig.handleArenaSize, driverConfig.disableHandleUseAfterFreeCheck,
               driverConfig.disableHeapHandleTags),
       mAllocator(createAllocator(mPlatform->getInstance(), mPlatform->getPhysicalDevice(),
               mPlatform->getDevice())),
@@ -212,12 +211,15 @@ VulkanDriver::VulkanDriver(VulkanPlatform* platform, VulkanContext const& contex
       mPipelineCache(mPlatform->getDevice()),
       mStagePool(mAllocator, &mCommands),
       mFramebufferCache(mPlatform->getDevice()),
+      mYcbcrConversionCache(mPlatform->getDevice()),
       mSamplerCache(mPlatform->getDevice()),
       mBlitter(mPlatform->getPhysicalDevice(), &mCommands),
       mReadPixels(mPlatform->getDevice()),
       mDescriptorSetLayoutCache(mPlatform->getDevice(), &mResourceManager),
       mDescriptorSetCache(mPlatform->getDevice(), &mResourceManager),
       mQueryManager(mPlatform->getDevice()),
+      mExternalImageManager(platform, &mSamplerCache, &mYcbcrConversionCache, &mDescriptorSetCache,
+              &mDescriptorSetLayoutCache),
       mIsSRGBSwapChainSupported(mPlatform->getCustomization().isSRGBSwapChainSupported),
       mStereoscopicType(driverConfig.stereoscopicType) {
 
@@ -248,7 +250,7 @@ VulkanDriver::~VulkanDriver() noexcept = default;
 
 UTILS_NOINLINE
 Driver* VulkanDriver::create(VulkanPlatform* platform, VulkanContext const& context,
-         Platform::DriverConfig const& driverConfig) noexcept {
+         Platform::DriverConfig const& driverConfig) {
 #if 0
     // this is useful for development, but too verbose even for debug builds
     // For reference on a 64-bits machine in Release mode:
@@ -310,7 +312,7 @@ void VulkanDriver::terminate() {
 
     mCurrentSwapChain = {};
     mDefaultRenderTarget = {};
-    mBoundPipeline = {};
+    mPipelineState = {};
 
     mQueryManager.terminate();
 
@@ -322,9 +324,13 @@ void VulkanDriver::terminate() {
 
     mCommands.terminate();
 
+    // Must come before samplerCache, ycbcrConversionCache, descriptorSetCache,
+    // descriptorSetLayoutCache
+    mExternalImageManager.terminate();
+
     mStagePool.terminate();
     mPipelineCache.terminate();
-    mFramebufferCache.reset();
+    mFramebufferCache.terminate();
     mSamplerCache.terminate();
     mDescriptorSetLayoutCache.terminate();
     mDescriptorSetCache.terminate();
@@ -363,7 +369,7 @@ void VulkanDriver::collectGarbage() {
     FVK_SYSTRACE_SCOPE();
     // Command buffers need to be submitted and completed before other resources can be gc'd.
     mCommands.gc();
-    mDescriptorSetCache.clearHistory();
+    mDescriptorSetCache.gc();
     mStagePool.gc();
     mFramebufferCache.gc();
     mPipelineCache.gc();
@@ -378,6 +384,10 @@ void VulkanDriver::beginFrame(int64_t monotonic_clock_ns,
         int64_t refreshIntervalNs, uint32_t frameId) {
     FVK_PROFILE_MARKER(PROFILE_NAME_BEGINFRAME);
     // Do nothing.
+
+    if (mAppState.hasExternalSamplers()) {
+        mExternalImageManager.onBeginFrame();
+    }
 }
 
 void VulkanDriver::setFrameScheduledCallback(Handle<HwSwapChain> sch, CallbackHandler* handler,
@@ -418,8 +428,17 @@ void VulkanDriver::updateDescriptorSetTexture(
     auto set = resource_ptr<VulkanDescriptorSet>::cast(&mResourceManager, dsh);
     auto texture = resource_ptr<VulkanTexture>::cast(&mResourceManager, th);
 
-    VkSampler const vksampler = mSamplerCache.getSampler(params);
-    mDescriptorSetCache.updateSampler(set, binding, texture, vksampler);
+    if (mExternalImageManager.isExternallySampledTexture(texture)) {
+        mExternalImageManager.bindExternallySampledTexture(set, binding, texture, params);
+        mAppState.hasBoundExternalImages = true;
+    } else {
+        VulkanSamplerCache::Params cacheParams = {
+            .sampler = params,
+        };
+        VkSampler const vksampler = mSamplerCache.getSampler(cacheParams);
+        mDescriptorSetCache.updateSampler(set, binding, texture, vksampler);
+        mExternalImageManager.clearTextureBinding(set, binding);
+    }
 }
 
 void VulkanDriver::flush(int) {
@@ -439,6 +458,7 @@ void VulkanDriver::finish(int dummy) {
 void VulkanDriver::createRenderPrimitiveR(Handle<HwRenderPrimitive> rph,
         Handle<HwVertexBuffer> vbh, Handle<HwIndexBuffer> ibh,
         PrimitiveType pt) {
+    FVK_SYSTRACE_SCOPE();
     auto vb = resource_ptr<VulkanVertexBuffer>::cast(&mResourceManager, vbh);
     auto ib = resource_ptr<VulkanIndexBuffer>::cast(&mResourceManager, ibh);
     auto ptr = resource_ptr<VulkanRenderPrimitive>::make(&mResourceManager, rph, pt, vb, ib);
@@ -449,12 +469,14 @@ void VulkanDriver::destroyRenderPrimitive(Handle<HwRenderPrimitive> rph) {
     if (!rph) {
         return;
     }
+    FVK_SYSTRACE_SCOPE();
     auto ptr = resource_ptr<VulkanRenderPrimitive>::cast(&mResourceManager, rph);
     ptr.dec();
 }
 
 void VulkanDriver::createVertexBufferInfoR(Handle<HwVertexBufferInfo> vbih, uint8_t bufferCount,
         uint8_t attributeCount, AttributeArray attributes) {
+    FVK_SYSTRACE_SCOPE();
     auto vbi = resource_ptr<VulkanVertexBufferInfo>::make(&mResourceManager, vbih, bufferCount,
             attributeCount, attributes);
     vbi.inc();
@@ -464,12 +486,14 @@ void VulkanDriver::destroyVertexBufferInfo(Handle<HwVertexBufferInfo> vbih) {
     if (!vbih) {
         return;
     }
+    FVK_SYSTRACE_SCOPE();
     auto vbi = resource_ptr<VulkanVertexBufferInfo>::cast(&mResourceManager, vbih);
     vbi.dec();
 }
 
 void VulkanDriver::createVertexBufferR(Handle<HwVertexBuffer> vbh, uint32_t vertexCount,
         Handle<HwVertexBufferInfo> vbih) {
+    FVK_SYSTRACE_SCOPE();
     auto vbi = resource_ptr<VulkanVertexBufferInfo>::cast(&mResourceManager, vbih);
     auto vb = resource_ptr<VulkanVertexBuffer>::make(&mResourceManager, vbh, mContext, mStagePool,
             vertexCount, vbi);
@@ -480,12 +504,14 @@ void VulkanDriver::destroyVertexBuffer(Handle<HwVertexBuffer> vbh) {
     if (!vbh) {
         return;
     }
+    FVK_SYSTRACE_SCOPE();
     auto vb = resource_ptr<VulkanVertexBuffer>::cast(&mResourceManager, vbh);
     vb.dec();
 }
 
 void VulkanDriver::createIndexBufferR(Handle<HwIndexBuffer> ibh, ElementType elementType,
         uint32_t indexCount, BufferUsage usage) {
+    FVK_SYSTRACE_SCOPE();
     auto elementSize = (uint8_t) getElementTypeSize(elementType);
     auto ib = resource_ptr<VulkanIndexBuffer>::make(&mResourceManager, ibh, mAllocator, mStagePool,
             elementSize, indexCount);
@@ -496,12 +522,14 @@ void VulkanDriver::destroyIndexBuffer(Handle<HwIndexBuffer> ibh) {
     if (!ibh) {
         return;
     }
+    FVK_SYSTRACE_SCOPE();
     auto ib = resource_ptr<VulkanIndexBuffer>::cast(&mResourceManager, ibh);
     ib.dec();
 }
 
 void VulkanDriver::createBufferObjectR(Handle<HwBufferObject> boh, uint32_t byteCount,
         BufferObjectBinding bindingType, BufferUsage usage) {
+    FVK_SYSTRACE_SCOPE();
     auto bo = resource_ptr<VulkanBufferObject>::make(&mResourceManager, boh, mAllocator, mStagePool,
             byteCount, bindingType);
     bo.inc();
@@ -511,6 +539,7 @@ void VulkanDriver::destroyBufferObject(Handle<HwBufferObject> boh) {
     if (!boh) {
         return;
     }
+    FVK_SYSTRACE_SCOPE();
     auto bo = resource_ptr<VulkanBufferObject>::cast(&mResourceManager, boh);
     bo.dec();
 }
@@ -556,39 +585,48 @@ void VulkanDriver::createTextureExternalImage2R(Handle<HwTexture> th, backend::S
         backend::TextureFormat format, uint32_t width, uint32_t height, backend::TextureUsage usage,
         Platform::ExternalImageHandleRef externalImage) {
     FVK_SYSTRACE_SCOPE();
-    const auto& metadata = mPlatform->getExternalImageMetadata(externalImage);
-    if (metadata.isProtected) {
-        usage |= backend::TextureUsage::PROTECTED;
-    }
-
-    VkImageUsageFlags vkUsage = metadata.usage;
-    if (any(usage & TextureUsage::BLIT_SRC)) {
-        vkUsage |= VK_IMAGE_USAGE_TRANSFER_SRC_BIT;
-    }
-
-    if (any(usage & (TextureUsage::BLIT_DST & TextureUsage::UPLOADABLE))) {
-        vkUsage |= VK_IMAGE_USAGE_TRANSFER_DST_BIT;
-    }
+    auto metadata = mPlatform->extractExternalImageMetadata(externalImage);
 
     assert_invariant(width == metadata.width);
     assert_invariant(height == metadata.height);
-    assert_invariant(fvkutils::getVkFormat(format) == metadata.format);
 
-    VkMemoryPropertyFlags const requiredMemoryFlags = any(usage & TextureUsage::UPLOADABLE)
-                                                              ? VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT
-                                                              : VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT;
-    uint32_t const memoryTypeIndex =
-            mContext.selectMemoryType(metadata.memoryTypeBits, requiredMemoryFlags);
-    FILAMENT_CHECK_POSTCONDITION(memoryTypeIndex != VK_MAX_MEMORY_TYPES)
-            << "failed to find a valid memory type for external image memory.";
+    // We do not check the format since AHB could return both a known format and an external format.
+    // In which case, we choose one or the other, but this choice is not known to the client.
+    // Therefore the following lines are commented out.
+    // assert_invariant(format == metadata.filamentFormat);
+    // assert_invariant(fvkutils::getVkFormat(format) == metadata.format);
 
-    const auto& data =
-            mPlatform->createExternalImageData(externalImage, metadata, memoryTypeIndex, vkUsage);
+    auto imgData = mPlatform->createVkImageFromExternal(externalImage);
 
-    auto texture = resource_ptr<VulkanTexture>::make(&mResourceManager, th, mPlatform->getDevice(),
-            mAllocator, &mResourceManager, &mCommands, data.first, data.second, metadata.format,
-            metadata.samples, metadata.width, metadata.height, metadata.layerCount, usage,
-            mStagePool);
+    assert_invariant(imgData.internal.valid() || imgData.external.valid());
+
+    VkFormat vkformat = metadata.format;
+    VkImage vkimage = VK_NULL_HANDLE;
+    VkDeviceMemory memory = VK_NULL_HANDLE;
+    if (imgData.internal.valid()) {
+        metadata.externalFormat = 0;
+        vkimage = imgData.internal.image;
+        memory = imgData.internal.memory;
+    } else { // imgData.external.valid()
+        vkformat = VK_FORMAT_UNDEFINED;
+        vkimage = imgData.external.image;
+        memory = imgData.external.memory;
+    }
+
+    VkSamplerYcbcrConversion const conversion =
+            mExternalImageManager.getVkSamplerYcbcrConversion(metadata);
+    auto texture = resource_ptr<VulkanTexture>::make(&mResourceManager, th, mContext,
+            mPlatform->getDevice(), mAllocator, &mResourceManager, &mCommands, vkimage, memory,
+            vkformat, conversion, metadata.samples, metadata.width, metadata.height,
+            metadata.layers, usage, mStagePool);
+    auto& commands = mCommands.get();
+    // Unlike uploaded textures or swapchains, we need to explicit transition this
+    // texture into the read layout.
+    texture->transitionLayout(&commands, texture->getPrimaryViewRange(), VulkanLayout::READ_ONLY);
+
+    if (imgData.external.valid()) {
+        mExternalImageManager.addExternallySampledTexture(texture, externalImage);
+    }
 
     texture.inc();
 }
@@ -597,13 +635,14 @@ void VulkanDriver::createTextureExternalImageR(Handle<HwTexture> th, backend::Sa
         backend::TextureFormat format, uint32_t width, uint32_t height, backend::TextureUsage usage,
         void* externalImage) {
     FVK_SYSTRACE_SCOPE();
-
+    assert_invariant(false && "Not supported in Vulkan backend");
     // not supported in this backend
 }
 
 void VulkanDriver::createTextureExternalImagePlaneR(Handle<HwTexture> th,
         backend::TextureFormat format, uint32_t width, uint32_t height, backend::TextureUsage usage,
         void* image, uint32_t plane) {
+    assert_invariant(false && "Not supported in Vulkan backend");
 }
 
 void VulkanDriver::importTextureR(Handle<HwTexture> th, intptr_t id,
@@ -611,6 +650,7 @@ void VulkanDriver::importTextureR(Handle<HwTexture> th, intptr_t id,
         TextureFormat format, uint8_t samples, uint32_t w, uint32_t h, uint32_t depth,
         TextureUsage usage) {
     // not supported in this backend
+    assert_invariant(false && "Not supported in Vulkan backend");
 }
 
 void VulkanDriver::destroyTexture(Handle<HwTexture> th) {
@@ -619,6 +659,8 @@ void VulkanDriver::destroyTexture(Handle<HwTexture> th) {
     }
     auto texture = resource_ptr<VulkanTexture>::cast(&mResourceManager, th);
     texture.dec();
+
+    mExternalImageManager.removeExternallySampledTexture(texture);
 }
 
 void VulkanDriver::createProgramR(Handle<HwProgram> ph, Program&& program) {
@@ -735,6 +777,7 @@ void VulkanDriver::createFenceR(Handle<HwFence> fh, int) {
 }
 
 void VulkanDriver::createSwapChainR(Handle<HwSwapChain> sch, void* nativeWindow, uint64_t flags) {
+    FVK_SYSTRACE_SCOPE();
     // Running gc() to guard against an edge case where the old swapchains need to have been
     // destroyed before the new swapchain can be created. Otherwise, we would fail
     // vkCreateSwapchainKHR with VK_ERROR_NATIVE_WINDOW_IN_USE_KHR.
@@ -776,6 +819,7 @@ void VulkanDriver::createTimerQueryR(Handle<HwTimerQuery> tqh, int) {
 
 void VulkanDriver::createDescriptorSetLayoutR(Handle<HwDescriptorSetLayout> dslh,
         backend::DescriptorSetLayout&& info) {
+    FVK_SYSTRACE_SCOPE();
     auto layout = mDescriptorSetLayoutCache.createLayout(dslh, std::move(info));
     layout.inc();
 }
@@ -787,6 +831,10 @@ void VulkanDriver::createDescriptorSetR(Handle<HwDescriptorSet> dsh,
             fvkmemory::resource_ptr<VulkanDescriptorSetLayout>::cast(&mResourceManager, dslh);
     auto set = mDescriptorSetCache.createSet(dsh, layout);
     set.inc();
+
+    if (layout->hasExternalSamplers()) {
+        mAppState.hasExternalSamplerLayouts = true;
+    }
 }
 
 Handle<HwVertexBufferInfo> VulkanDriver::createVertexBufferInfoS() noexcept {
@@ -911,6 +959,10 @@ void VulkanDriver::destroyDescriptorSetLayout(Handle<HwDescriptorSetLayout> dslh
 void VulkanDriver::destroyDescriptorSet(Handle<HwDescriptorSet> dsh) {
     auto set = resource_ptr<VulkanDescriptorSet>::cast(&mResourceManager, dsh);
     set.dec();
+
+    if (mAppState.hasExternalSamplers() && set->getExternalSamplerVkSet() != VK_NULL_HANDLE) {
+        mExternalImageManager.removeDescriptorSet(set);
+    }
 }
 
 Handle<HwStream> VulkanDriver::createStreamNative(void* nativeStream) {
@@ -1471,7 +1523,6 @@ void VulkanDriver::endRenderPass(int) {
     // pipeline barrier between framebuffer writes and shader reads.
     rt->emitBarriersEndRenderPass(*mCurrentRenderPass.commandBuffer);
 
-    mRenderPassFboInfo = {};
     mCurrentRenderPass.renderTarget = {};
     mCurrentRenderPass.renderPass = VK_NULL_HANDLE;
 
@@ -1512,7 +1563,7 @@ void VulkanDriver::makeCurrent(Handle<HwSwapChain> drawSch, Handle<HwSwapChain>
     swapChain->acquire(resized);
 
     if (resized) {
-        mFramebufferCache.reset();
+        mFramebufferCache.resetFramebuffers();
     }
 
     if (UTILS_LIKELY(mDefaultRenderTarget)) {
@@ -1531,10 +1582,10 @@ void VulkanDriver::commit(Handle<HwSwapChain> sch) {
 
 void VulkanDriver::setPushConstant(backend::ShaderStage stage, uint8_t index,
         backend::PushConstantVariant value) {
-    assert_invariant(mBoundPipeline.program && "Expect a program when writing to push constants");
+    assert_invariant(mPipelineState.program && "Expect a program when writing to push constants");
     assert_invariant(mCurrentRenderPass.commandBuffer && "Should be called within a renderpass");
-    mBoundPipeline.program->writePushConstant(mCurrentRenderPass.commandBuffer->buffer(),
-            mBoundPipeline.pipelineLayout, stage, index, value);
+    mPipelineState.program->writePushConstant(mCurrentRenderPass.commandBuffer->buffer(),
+            mPipelineState.pipelineLayout, stage, index, value);
 }
 
 void VulkanDriver::insertEventMarker(char const* string) {
@@ -1713,16 +1764,69 @@ void VulkanDriver::blitDEPRECATED(TargetBufferFlags buffers,
 }
 
 void VulkanDriver::bindPipeline(PipelineState const& pipelineState) {
+    // This resets all of the pipeline states; the most relevant (needing reset) is .bindInDraw.
+    mPipelineState = {};
+
+    auto& setLayouts = pipelineState.pipelineLayout.setLayout;
+    DescriptorSetLayoutHandleList layoutHandles;
+    uint8_t layoutCount = 0;
+    std::transform(setLayouts.begin(), setLayouts.end(), layoutHandles.begin(),
+            [&](auto const& handle) -> resource_ptr<VulkanDescriptorSetLayout> {
+                if (!handle) {
+                    return {};
+                }
+                layoutCount++;
+                return resource_ptr<VulkanDescriptorSetLayout>::cast(&mResourceManager, handle);
+            });
+
+    constexpr uint8_t descriptorSetMaskTable[4] = {0x1, 0x3, 0x7, 0xF};
+    fvkutils::DescriptorSetMask const descriptorSetMask =
+            fvkutils::DescriptorSetMask(descriptorSetMaskTable[layoutCount]);
+
+    if (mAppState.hasExternalSamplers()) {
+        auto const haveExternalSamplers = [&](auto layoutHandle) {
+            if (!layoutHandle) {
+                return false;
+            }
+            return layoutHandle->hasExternalSamplers();
+        };
+        if (std::any_of(layoutHandles.begin(), layoutHandles.end(), haveExternalSamplers)) {
+            BindInDrawBundle bundle = {
+                .pipelineState = pipelineState,
+                .dsLayoutHandles = layoutHandles,
+                .descriptorSetMask = descriptorSetMask,
+            };
+            mPipelineState.bindInDraw = { true, bundle };
+            return;
+        }
+    }
+
+    // The normal, non-external sampler path
+    using VkDescriptorSetLayoutArray = VulkanPipelineLayoutCache::DescriptorSetLayoutArray;
+    VkDescriptorSetLayoutArray vkLayouts;
+    std::transform(layoutHandles.begin(), layoutHandles.end(), vkLayouts.begin(),
+            [](auto const& layout) -> VkDescriptorSetLayout {
+                if (!layout) {
+                    return VK_NULL_HANDLE;
+                }
+                return layout->getVkLayout();
+            });
+    auto program = resource_ptr<VulkanProgram>::cast(&mResourceManager, pipelineState.program);
+    auto pipelineLayout = mPipelineLayoutCache.getLayout(vkLayouts, program);
+    bindPipelineImpl(pipelineState, pipelineLayout, descriptorSetMask);
+}
+
+void VulkanDriver::bindPipelineImpl(PipelineState const& pipelineState,
+        VkPipelineLayout pipelineLayout, fvkutils::DescriptorSetMask descriptorSetMask) {
     FVK_SYSTRACE_SCOPE();
     auto commands = mCurrentRenderPass.commandBuffer;
     auto vbi = resource_ptr<VulkanVertexBufferInfo>::cast(&mResourceManager,
             pipelineState.vertexBufferInfo);
 
-    Handle<HwProgram> programHandle = pipelineState.program;
     RasterState const& rasterState = pipelineState.rasterState;
     PolygonOffset const& depthOffset = pipelineState.polygonOffset;
 
-    auto program = resource_ptr<VulkanProgram>::cast(&mResourceManager, programHandle);
+    auto program = resource_ptr<VulkanProgram>::cast(&mResourceManager, pipelineState.program);
     commands->acquire(program);
 
     // Update the VK raster state.
@@ -1764,28 +1868,11 @@ void VulkanDriver::bindPipeline(PipelineState const& pipelineState) {
     mPipelineCache.bindPrimitiveTopology(topology);
     mPipelineCache.bindVertexArray(attribDesc, bufferDesc, vbi->getAttributeCount());
 
-    auto& setLayouts = pipelineState.pipelineLayout.setLayout;
-    VulkanDescriptorSetLayout::DescriptorSetLayoutArray layoutList;
-    uint8_t layoutCount = 0;
-    std::transform(setLayouts.begin(), setLayouts.end(), layoutList.begin(),
-            [&](Handle<HwDescriptorSetLayout> handle) -> VkDescriptorSetLayout {
-                if (!handle) {
-                    return VK_NULL_HANDLE;
-                }
-                auto layout =
-                        resource_ptr<VulkanDescriptorSetLayout>::cast(&mResourceManager, handle);
-                layoutCount++;
-                return layout->getVkLayout();
-            });
-    auto pipelineLayout = mPipelineLayoutCache.getLayout(layoutList, program);
-
-    constexpr uint8_t descriptorSetMaskTable[4] = {0x1, 0x3, 0x7, 0xF};
-
-    mBoundPipeline = {
-        .program = program,
-        .pipelineLayout = pipelineLayout,
-        .descriptorSetMask = fvkutils::DescriptorSetMask(descriptorSetMaskTable[layoutCount]),
-    };
+    // Note that we cannot reinit mPipeline because the .bindInDraw metadata that needs to carry
+    // over even on bind.
+    mPipelineState.program = program;
+    mPipelineState.pipelineLayout = pipelineLayout;
+    mPipelineState.descriptorSetMask = descriptorSetMask;
 
     mPipelineCache.bindLayout(pipelineLayout);
     mPipelineCache.bindPipeline(mCurrentRenderPass.commandBuffer);
@@ -1830,15 +1917,41 @@ void VulkanDriver::bindDescriptorSet(
 void VulkanDriver::draw2(uint32_t indexOffset, uint32_t indexCount, uint32_t instanceCount) {
     FVK_SYSTRACE_SCOPE();
     VkCommandBuffer cmdbuffer = mCurrentRenderPass.commandBuffer->buffer();
+    auto const& [doBindInDraw, bundle] = mPipelineState.bindInDraw;
 
-    mDescriptorSetCache.commit(mCurrentRenderPass.commandBuffer,
-            mBoundPipeline.pipelineLayout,
-            mBoundPipeline.descriptorSetMask);
+    fvkutils::DescriptorSetMask setsWithExternalSamplers = {};
+    if (doBindInDraw) {
+        auto& layoutHandles = bundle.dsLayoutHandles;
+        setsWithExternalSamplers = mExternalImageManager.prepareBindSets(layoutHandles,
+                mDescriptorSetCache.getBoundSets());
+
+        VulkanDescriptorSetLayout::DescriptorSetLayoutArray vklayouts;
+        for (size_t i = 0; i < layoutHandles.size(); i++) {
+            if (!layoutHandles[i]) {
+                vklayouts[i] = VK_NULL_HANDLE;
+                continue;
+            }
+            if (setsWithExternalSamplers[i]) {
+                vklayouts[i] = layoutHandles[i]->getExternalSamplerVkLayout();
+            } else {
+                vklayouts[i] = layoutHandles[i]->getVkLayout();
+            }
+        }
+        auto program =
+                resource_ptr<VulkanProgram>::cast(&mResourceManager, bundle.pipelineState.program);
+        VkPipelineLayout const pipelineLayout = mPipelineLayoutCache.getLayout(vklayouts, program);
+        if (pipelineLayout != mPipelineState.pipelineLayout) {
+            bindPipelineImpl(bundle.pipelineState, pipelineLayout, bundle.descriptorSetMask);
+        }
+        mPipelineState.bindInDraw.first = false;
+    }
+    mDescriptorSetCache.commit(mCurrentRenderPass.commandBuffer, mPipelineState.pipelineLayout,
+            setsWithExternalSamplers, mPipelineState.descriptorSetMask);
 
     // Finally, make the actual draw call. TODO: support subranges
-    const uint32_t firstIndex = indexOffset;
-    const int32_t vertexOffset = 0;
-    const uint32_t firstInstId = 0;
+    uint32_t const firstIndex = indexOffset;
+    constexpr int32_t vertexOffset = 0;
+    constexpr uint32_t firstInstId = 0;
 
     vkCmdDrawIndexed(cmdbuffer, indexCount, instanceCount, firstIndex, vertexOffset, firstInstId);
 }

filament/backend/src/vulkan/VulkanDriver.h

@@ -27,8 +27,10 @@
 #include "VulkanSamplerCache.h"
 #include "VulkanStagePool.h"
 #include "VulkanQueryManager.h"
+#include "VulkanYcbcrConversionCache.h"
 #include "vulkan/VulkanDescriptorSetCache.h"
 #include "vulkan/VulkanDescriptorSetLayoutCache.h"
+#include "vulkan/VulkanExternalImageManager.h"
 #include "vulkan/VulkanPipelineLayoutCache.h"
 #include "vulkan/memory/ResourceManager.h"
 #include "vulkan/memory/ResourcePointer.h"
@@ -53,7 +55,7 @@ constexpr uint8_t MAX_RENDERTARGET_ATTACHMENT_TEXTURES =
 class VulkanDriver final : public DriverBase {
 public:
     static Driver* create(VulkanPlatform* platform, VulkanContext const& context,
-            Platform::DriverConfig const& driverConfig) noexcept;
+            Platform::DriverConfig const& driverConfig);
 
 #if FVK_ENABLED(FVK_DEBUG_DEBUG_UTILS)
     // Encapsulates the VK_EXT_debug_utils extension.  In particular, we use
@@ -88,8 +90,8 @@ private:
     void debugCommandBegin(CommandStream* cmds, bool synchronous,
             const char* methodName) noexcept override;
 
-    inline VulkanDriver(VulkanPlatform* platform, VulkanContext const& context,
-            Platform::DriverConfig const& driverConfig) noexcept;
+    VulkanDriver(VulkanPlatform* platform, VulkanContext const& context,
+            Platform::DriverConfig const& driverConfig);
 
     ~VulkanDriver() noexcept override;
 
@@ -118,6 +120,8 @@ private:
 
 private:
     void collectGarbage();
+    void bindPipelineImpl(PipelineState const& pipelineState, VkPipelineLayout pipelineLayout,
+            fvkutils::DescriptorSetMask descriptorSetMask);
 
     VulkanPlatform* mPlatform = nullptr;
     fvkmemory::ResourceManager mResourceManager;
@@ -135,27 +139,46 @@ private:
     VulkanPipelineCache mPipelineCache;
     VulkanStagePool mStagePool;
     VulkanFboCache mFramebufferCache;
+    VulkanYcbcrConversionCache mYcbcrConversionCache;
     VulkanSamplerCache mSamplerCache;
     VulkanBlitter mBlitter;
     VulkanReadPixels mReadPixels;
     VulkanDescriptorSetLayoutCache mDescriptorSetLayoutCache;
     VulkanDescriptorSetCache mDescriptorSetCache;
     VulkanQueryManager mQueryManager;
+    VulkanExternalImageManager mExternalImageManager;
 
     // This is necessary for us to write to push constants after binding a pipeline.
-    struct {
-        resource_ptr<VulkanProgram> program;
-        VkPipelineLayout pipelineLayout;
-        fvkutils::DescriptorSetMask descriptorSetMask;
-    } mBoundPipeline = {};
+    using DescriptorSetLayoutHandleList = std::array<resource_ptr<VulkanDescriptorSetLayout>,
+            VulkanDescriptorSetLayout::UNIQUE_DESCRIPTOR_SET_COUNT>;
+
+    struct BindInDrawBundle {
+        PipelineState pipelineState = {};
+        DescriptorSetLayoutHandleList dsLayoutHandles = {};
+        fvkutils::DescriptorSetMask descriptorSetMask = {};
+        resource_ptr<VulkanProgram> program = {};
+    };
 
-    // We need to store information about a render pass to enable better barriers at the end of a
-    // renderpass.
     struct {
-        using AttachmentArray =
-                fvkutils::StaticVector<VulkanAttachment, MAX_RENDERTARGET_ATTACHMENT_TEXTURES>;
-        AttachmentArray attachments;
-    } mRenderPassFboInfo = {};
+        // For push constant
+        resource_ptr<VulkanProgram> program = {};
+        // For push commiting dynamic ubos in draw()
+        VkPipelineLayout pipelineLayout = VK_NULL_HANDLE;
+        fvkutils::DescriptorSetMask descriptorSetMask = {};
+
+        std::pair<bool, BindInDrawBundle> bindInDraw = {false, {}};
+    } mPipelineState = {};
+
+    struct {
+        // This tracks whether the app has seen external samplers bound to a the descriptor set.
+        // This will force bindPipeline to take a slow path.
+        bool hasExternalSamplerLayouts = false;
+        bool hasBoundExternalImages = false;
+
+        bool hasExternalSamplers() const noexcept {
+            return hasExternalSamplerLayouts && hasBoundExternalImages;
+        }
+    } mAppState;
 
     bool const mIsSRGBSwapChainSupported;
     backend::StereoscopicType const mStereoscopicType;

filament/backend/src/vulkan/VulkanExternalImageManager.cpp

@@ -0,0 +1,294 @@
+/*
+ * Copyright (C) 2025 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "VulkanExternalImageManager.h"
+
+#include "VulkanDescriptorSetCache.h"
+#include "VulkanDescriptorSetLayoutCache.h"
+#include "VulkanSamplerCache.h"
+#include "VulkanYcbcrConversionCache.h"
+#include "vulkan/memory/ResourcePointer.h"
+#include "vulkan/utils/Conversion.h"
+
+#include <backend/platforms/VulkanPlatform.h>
+
+#include <algorithm>
+
+namespace filament::backend {
+
+namespace {
+
+using Bitmask = fvkutils::UniformBufferBitmask;
+static_assert(sizeof(Bitmask) * 8 == fvkutils::MAX_DESCRIPTOR_SET_BITMASK_BITS);
+
+template<typename T>
+void erasep(std::vector<T>& v, std::function<bool(T const&)> f) {
+    auto newEnd = std::remove_if(v.begin(), v.end(), f);
+    v.erase(newEnd, v.end());
+}
+
+using ImageData = VulkanExternalImageManager::VulkanExternalImageManager::ImageData;
+ImageData& findImage(std::vector<ImageData>& images,
+        fvkmemory::resource_ptr<VulkanTexture> texture) {
+    auto itr = std::find_if(images.begin(), images.end(), [&](ImageData const& data) {
+        return data.image == texture;
+    });
+    assert_invariant(itr != images.end());
+    return *itr;
+}
+
+void copySet(VkDevice device, VkDescriptorSet srcSet, VkDescriptorSet dstSet, Bitmask bindings) {
+    // TODO: fix the size for better memory management
+    std::vector<VkCopyDescriptorSet> copies;
+    bindings.forEachSetBit([&](size_t index) {
+        copies.push_back({
+            .sType = VK_STRUCTURE_TYPE_COPY_DESCRIPTOR_SET,
+            .srcSet = srcSet,
+            .srcBinding = (uint32_t) index,
+            .dstSet = dstSet,
+            .dstBinding = (uint32_t) index,
+            .descriptorCount = 1,
+        });
+    });
+    vkUpdateDescriptorSets(device, 0, nullptr, copies.size(), copies.data());
+}
+
+Bitmask foldBitsInHalf(Bitmask bitset) {
+    Bitmask outBitset;
+    bitset.forEachSetBit([&](size_t index) {
+        constexpr size_t BITMASK_LOWER_BITS_LEN = sizeof(outBitset) * 4;
+        outBitset.set(index % BITMASK_LOWER_BITS_LEN);
+    });
+    return outBitset;
+}
+
+}// namespace
+
+VulkanExternalImageManager::VulkanExternalImageManager(VulkanPlatform* platform,
+        VulkanSamplerCache* samplerCache, VulkanYcbcrConversionCache* ycbcrConversionCache,
+        VulkanDescriptorSetCache* setCache, VulkanDescriptorSetLayoutCache* layoutCache)
+    : mPlatform(platform),
+      mSamplerCache(samplerCache),
+      mYcbcrConversionCache(ycbcrConversionCache),
+      mDescriptorSetCache(setCache),
+      mDescriptorSetLayoutCache(layoutCache) {
+}
+
+VulkanExternalImageManager::~VulkanExternalImageManager() = default;
+
+void VulkanExternalImageManager::terminate() {
+    mSetBindings.clear();
+    mImages.clear();
+}
+
+void VulkanExternalImageManager::onBeginFrame() {
+    std::for_each(mImages.begin(), mImages.end(), [](ImageData& image) {
+        image.hasBeenValidated = false;
+    });
+    std::for_each(mSetBindings.begin(), mSetBindings.end(), [](SetBindingInfo& info) {
+        info.bound = false;
+    });
+}
+
+fvkutils::DescriptorSetMask VulkanExternalImageManager::prepareBindSets(LayoutArray const& layouts,
+        SetArray const& sets) {
+    fvkutils::DescriptorSetMask shouldUseExternalSampler{};
+    for (uint8_t i = 0; i < sets.size(); i++) {
+        auto set = sets[i];
+        auto layout = layouts[i];
+        if (!set || !layout) {
+            continue;
+        }
+        if (hasExternalSampler(set)) {
+            updateSetAndLayout(set, layout);
+            shouldUseExternalSampler.set(i);
+        }
+    }
+    return shouldUseExternalSampler;
+}
+
+bool VulkanExternalImageManager::hasExternalSampler(
+        fvkmemory::resource_ptr<VulkanDescriptorSet> set) {
+    auto itr = std::find_if(mSetBindings.begin(), mSetBindings.end(),
+            [&](SetBindingInfo const& info) { return info.set == set; });
+    return itr != mSetBindings.end();
+}
+
+void VulkanExternalImageManager::updateSetAndLayout(
+        fvkmemory::resource_ptr<VulkanDescriptorSet> set,
+        fvkmemory::resource_ptr<VulkanDescriptorSetLayout> layout) {
+    utils::FixedCapacityVector<
+            std::tuple<uint8_t, VkSampler, fvkmemory::resource_ptr<VulkanTexture>>>
+            samplerAndBindings;
+    samplerAndBindings.reserve(MAX_SAMPLER_COUNT);
+
+    fvkutils::SamplerBitmask actualExternalSamplers;
+    for (auto& bindingInfo : mSetBindings) {
+        if (bindingInfo.set != set || bindingInfo.bound) {
+            continue;
+        }
+        auto& imageData = findImage(mImages, bindingInfo.image);
+        updateImage(&imageData);
+
+        auto samplerParams = bindingInfo.samplerParams;
+        // according to spec, these must match chromaFilter
+        // https://registry.khronos.org/vulkan/specs/latest/man/html/VkSamplerCreateInfo.html#VUID-VkSamplerCreateInfo-minFilter-01645
+        samplerParams.filterMag = SamplerMagFilter::NEAREST;
+        samplerParams.filterMin = SamplerMinFilter::NEAREST;
+
+        auto sampler = mSamplerCache->getSampler({
+            .sampler = samplerParams,
+            .conversion = imageData.conversion,
+        });
+        actualExternalSamplers.set(bindingInfo.binding);
+        samplerAndBindings.push_back({ bindingInfo.binding, sampler, bindingInfo.image });
+        bindingInfo.bound = true;
+    }
+
+    if (samplerAndBindings.empty()) {
+        return;
+    }
+
+    // Sort by binding number
+    std::sort(samplerAndBindings.begin(), samplerAndBindings.end(), [](auto const& a, auto const& b) {
+        return std::get<0>(a) < std::get<0>(b);
+    });
+
+    utils::FixedCapacityVector<VkSampler> outSamplers;
+    outSamplers.reserve(MAX_SAMPLER_COUNT);
+    std::for_each(samplerAndBindings.begin(), samplerAndBindings.end(),
+            [&](auto const& b) { outSamplers.push_back(std::get<1>(b)); });
+
+    VkDescriptorSetLayout const oldLayout = layout->getExternalSamplerVkLayout();
+    VkDescriptorSetLayout const newLayout = mDescriptorSetLayoutCache->getVkLayout(layout->bitmask,
+            actualExternalSamplers, outSamplers);
+
+    // Need to copy the set
+    VkDescriptorSet const oldSet = set->getExternalSamplerVkSet();
+    if (oldLayout != newLayout || oldSet == VK_NULL_HANDLE) {
+        // Build a new descriptor set from the new layout
+        VkDescriptorSet const newSet = mDescriptorSetCache->getVkSet(layout->count, newLayout);
+        auto const ubo = layout->bitmask.ubo | layout->bitmask.dynamicUbo;
+        auto const samplers = layout->bitmask.sampler & (~actualExternalSamplers);
+
+        // Each bitmask denotes a binding index, and separated into two stages - vertex and buffer
+        // We fold the two stages into just the lower half of the bits to denote a combined set of
+        // bindings.
+        Bitmask const copyBindings = foldBitsInHalf(ubo | samplers);
+        VkDescriptorSet const srcSet = oldSet != VK_NULL_HANDLE ? oldSet : set->getVkSet();
+        copySet(mPlatform->getDevice(), srcSet, newSet, copyBindings);
+
+        set->setExternalSamplerVkSet(newSet, [&](VulkanDescriptorSet*) {
+            mDescriptorSetCache->manualRecycle(layout->count, newLayout, newSet);
+        });
+        if (oldLayout != newLayout) {
+            layout->setExternalSamplerVkLayout(newLayout);
+        }
+    }
+
+    // Update the external samplers in the set
+    for (auto& [binding, sampler, image]: samplerAndBindings) {
+        mDescriptorSetCache->updateSamplerForExternalSamplerSet(set, binding, image);
+    }
+}
+
+VkSamplerYcbcrConversion VulkanExternalImageManager::getVkSamplerYcbcrConversion(
+        VulkanPlatform::ExternalImageMetadata const& metadata) {
+    // This external image does not require external sampler (YUV conversion).
+    if (metadata.externalFormat == 0 && !fvkutils::isVKYcbcrConversionFormat(metadata.format)) {
+        return VK_NULL_HANDLE;
+    }
+    VulkanYcbcrConversionCache::Params ycbcrParams = {
+        .conversion = {
+            .ycbcrModel = fvkutils::getYcbcrModelConversionFilament(metadata.ycbcrModel),
+            .r = fvkutils::getSwizzleFilament(metadata.ycbcrConversionComponents.r, 0),
+            .g = fvkutils::getSwizzleFilament(metadata.ycbcrConversionComponents.g, 1),
+            .b = fvkutils::getSwizzleFilament(metadata.ycbcrConversionComponents.b, 2),
+            .a = fvkutils::getSwizzleFilament(metadata.ycbcrConversionComponents.a, 3),
+            .ycbcrRange = fvkutils::getYcbcrRangeFilament(metadata.ycbcrRange),
+            .xChromaOffset = fvkutils::getChromaLocationFilament(metadata.xChromaOffset),
+            .yChromaOffset = fvkutils::getChromaLocationFilament(metadata.yChromaOffset),
+
+            // Unclear where to get the chromaFilter, we just assume it's nearest.
+            .chromaFilter = SamplerMagFilter::NEAREST,
+        },
+        .format = metadata.format,
+        .externalFormat = metadata.externalFormat,
+    };
+    return mYcbcrConversionCache->getConversion(ycbcrParams);
+}
+
+void VulkanExternalImageManager::updateImage(ImageData* image) {
+    if (image->hasBeenValidated) {
+        return;
+    }
+    image->hasBeenValidated = true;
+
+    auto metadata = mPlatform->extractExternalImageMetadata(image->platformHandle);
+    auto vkYcbcr = getVkSamplerYcbcrConversion(metadata);
+    if (vkYcbcr == image->conversion) {
+        return;
+    }
+
+    image->image->setYcbcrConversion(vkYcbcr);
+    image->conversion = vkYcbcr;
+    return;
+}
+
+void VulkanExternalImageManager::removeDescriptorSet(
+        fvkmemory::resource_ptr<VulkanDescriptorSet> inSet) {
+    erasep<SetBindingInfo>(mSetBindings,
+            [&](auto const& bindingInfo) { return (bindingInfo.set == inSet); });
+}
+
+void VulkanExternalImageManager::bindExternallySampledTexture(
+        fvkmemory::resource_ptr<VulkanDescriptorSet> set, uint8_t bindingPoint,
+        fvkmemory::resource_ptr<VulkanTexture> image, SamplerParams samplerParams) {
+    // Should we do duplicate validation here?
+    auto& imageData = findImage(mImages, image);
+    mSetBindings.push_back({ bindingPoint, imageData.image, set, samplerParams });
+}
+
+void VulkanExternalImageManager::addExternallySampledTexture(
+       fvkmemory::resource_ptr<VulkanTexture> image,
+        Platform::ExternalImageHandleRef platformHandleRef) {
+    mImages.push_back({ image, platformHandleRef, false });
+}
+
+void VulkanExternalImageManager::removeExternallySampledTexture(
+        fvkmemory::resource_ptr<VulkanTexture> image) {
+    erasep<SetBindingInfo>(mSetBindings,
+            [&](auto const& bindingInfo) { return (bindingInfo.image == image); });
+    erasep<ImageData>(mImages, [&](auto const& imageData) {
+        return imageData.image == image;
+    });
+}
+
+bool VulkanExternalImageManager::isExternallySampledTexture(
+        fvkmemory::resource_ptr<VulkanTexture> image) const {
+    return std::find_if(mImages.begin(), mImages.end(), [&](auto const& imageData) {
+        return imageData.image == image;
+    }) != mImages.end();
+}
+
+void VulkanExternalImageManager::clearTextureBinding(
+        fvkmemory::resource_ptr<VulkanDescriptorSet> set, uint8_t bindingPoint) {
+    erasep<SetBindingInfo>(mSetBindings, [&](auto const& bindingInfo) {
+        return (bindingInfo.set == set && bindingInfo.binding == bindingPoint);
+    });
+}
+
+} // namesapce filament::backend

filament/backend/src/vulkan/VulkanExternalImageManager.h

@@ -0,0 +1,121 @@
+/*
+ * Copyright (C) 2025 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef TNT_FILAMENT_BACKEND_CACHING_VULKANEXTERNALIMAGEMANAGER_H
+#define TNT_FILAMENT_BACKEND_CACHING_VULKANEXTERNALIMAGEMANAGER_H
+
+#include "VulkanHandles.h"
+
+#include <backend/DriverEnums.h>
+
+#include <array>
+#include <vector>
+
+namespace filament::backend {
+
+class VulkanYcbcrConversionCache;
+class VulkanSamplerCache;
+class VulkanDescriptorSetLayoutCache;
+class VulkanDescriptorSetCache;
+
+// Manages the logic of external images and their quirks wrt Vulikan.
+class VulkanExternalImageManager {
+public:
+
+    VulkanExternalImageManager(
+            VulkanPlatform* platform,
+            VulkanSamplerCache* samplerCache,
+            VulkanYcbcrConversionCache* ycbcrConversionCache,
+            VulkanDescriptorSetCache* setCache,
+            VulkanDescriptorSetLayoutCache* layoutCache);
+
+    ~VulkanExternalImageManager();
+
+    void terminate();
+
+    void onBeginFrame();
+
+    using SetArray = std::array<fvkmemory::resource_ptr<VulkanDescriptorSet>,
+            VulkanDescriptorSetLayout::UNIQUE_DESCRIPTOR_SET_COUNT>;
+
+    using LayoutArray = std::array<fvkmemory::resource_ptr<VulkanDescriptorSetLayout>,
+            VulkanDescriptorSetLayout::UNIQUE_DESCRIPTOR_SET_COUNT>;
+
+    using VkLayoutArray = VulkanDescriptorSetLayout::DescriptorSetLayoutArray;
+
+    // Returns  bitmask to indicate whether or not to use the external sampler version of each
+    // descriptor set.
+    fvkutils::DescriptorSetMask prepareBindSets(LayoutArray const& layouts, SetArray const& sets);
+
+    void removeDescriptorSet(fvkmemory::resource_ptr<VulkanDescriptorSet> set);
+
+    void bindExternallySampledTexture(fvkmemory::resource_ptr<VulkanDescriptorSet> set,
+            uint8_t bindingPoint, fvkmemory::resource_ptr<VulkanTexture> image,
+            SamplerParams samplerParams);
+
+    void clearTextureBinding(fvkmemory::resource_ptr<VulkanDescriptorSet> set,
+                             uint8_t bindingPoint);
+
+    void addExternallySampledTexture(fvkmemory::resource_ptr<VulkanTexture> external,
+            Platform::ExternalImageHandleRef platformHandleRef);
+
+    void removeExternallySampledTexture(fvkmemory::resource_ptr<VulkanTexture> image);
+
+    bool isExternallySampledTexture(fvkmemory::resource_ptr<VulkanTexture> image) const;
+
+    VkSamplerYcbcrConversion getVkSamplerYcbcrConversion(
+            VulkanPlatform::ExternalImageMetadata const& metadata);
+
+    struct ImageData {
+        fvkmemory::resource_ptr<VulkanTexture> image;
+        Platform::ExternalImageHandle platformHandle;
+        bool hasBeenValidated = false; // indicates whether the image has been validated *this frame*
+        VkSamplerYcbcrConversion conversion = VK_NULL_HANDLE;
+    };
+
+private:
+    bool hasExternalSampler(fvkmemory::resource_ptr<VulkanDescriptorSet> set);
+
+    void updateSetAndLayout(fvkmemory::resource_ptr<VulkanDescriptorSet> set,
+            fvkmemory::resource_ptr<VulkanDescriptorSetLayout> layout);
+
+    void updateImage(ImageData* imageData);
+
+    VulkanPlatform* mPlatform;
+    VulkanSamplerCache* mSamplerCache;
+    VulkanYcbcrConversionCache* mYcbcrConversionCache;
+    VulkanDescriptorSetCache* mDescriptorSetCache;
+    VulkanDescriptorSetLayoutCache* mDescriptorSetLayoutCache;
+
+    using SetAndLayout = std::pair<fvkmemory::resource_ptr<VulkanDescriptorSet>,
+            fvkmemory::resource_ptr<VulkanDescriptorSetLayout>>;
+
+    struct SetBindingInfo {
+        uint8_t binding = 0;
+        fvkmemory::resource_ptr<VulkanTexture> image;
+        fvkmemory::resource_ptr<VulkanDescriptorSet> set;
+        SamplerParams samplerParams;
+        bool bound = false;
+    };
+
+    // Use vectors instead of hash maps because we only expect small number of entries.
+    std::vector<SetBindingInfo> mSetBindings;
+    std::vector<ImageData> mImages;
+};
+
+} // filament::backend
+
+#endif // TNT_FILAMENT_BACKEND_CACHING_VULKANEXTERNALIMAGEMANAGER_H

filament/backend/src/vulkan/VulkanFboCache.cpp

@@ -330,25 +330,39 @@ VkRenderPass VulkanFboCache::getRenderPass(RenderPassKey const& config) noexcept
     mRenderPassCache[config] = {renderPass, mCurrentTime};
 
 #if FVK_ENABLED(FVK_DEBUG_FBO_CACHE)
-    FVK_LOGD << "Created render pass " << renderPass << " with "
-        << "samples = " << int(config.samples) << ", "
-        << "depth = " << (hasDepth ? 1 : 0) << ", "
-        << "colorAttachmentCount[0] = " << subpasses[0].colorAttachmentCount
-        << utils::io::endl;
-    #endif
+    FVK_LOGD << "Created render pass " << renderPass << " with ";
+    for (int i = 0; i < MRT::MAX_SUPPORTED_RENDER_TARGET_COUNT; ++i) {
+        FVK_LOGD << (int) config.colorFormat[i] << " ";
+    }
+    FVK_LOGD << ", "
+             << "depth = " << config.depthFormat << ", "
+             << "initialDepthLayout = " << (int) config.initialDepthLayout << ", "
+             << "samples = " << int(config.samples) << ", "
+             << "needsResolveMask = " << int(config.needsResolveMask) << ", "
+             << "usesLazilyAllocatedMemory = " << int(config.usesLazilyAllocatedMemory) << ", "
+             << "viewCount = " << int(config.viewCount) << ", "
+             << "colorAttachmentCount[0] = " << subpasses[0].colorAttachmentCount
+             << utils::io::endl;
+#endif
 
     return renderPass;
 }
 
-void VulkanFboCache::reset() noexcept {
-    for (auto pair : mFramebufferCache) {
+void VulkanFboCache::resetFramebuffers() noexcept {
+    for (const auto& pair: mFramebufferCache) {
         mRenderPassRefCount[pair.first.renderPass]--;
         vkDestroyFramebuffer(mDevice, pair.second.handle, VKALLOC);
     }
     mFramebufferCache.clear();
-    for (auto pair : mRenderPassCache) {
+}
+
+void VulkanFboCache::terminate() noexcept {
+    resetFramebuffers();
+
+    for (const auto& pair: mRenderPassCache) {
         vkDestroyRenderPass(mDevice, pair.second.handle, VKALLOC);
     }
+    mRenderPassRefCount.clear();
     mRenderPassCache.clear();
 }
 

filament/backend/src/vulkan/VulkanFboCache.h

@@ -106,8 +106,11 @@ public:
     // Evicts old unused Vulkan objects. Call this once per frame.
     void gc() noexcept;
 
+    // Frees all Framebuffer objects. Call this every time a the swapchain is resized
+    void resetFramebuffers() noexcept;
+
     // Frees all Vulkan objects. Call this during shutdown before the device is destroyed.
-    void reset() noexcept;
+    void terminate() noexcept;
 
 private:
     VkDevice mDevice;

filament/backend/src/vulkan/VulkanHandles.cpp

@@ -30,6 +30,7 @@
 
 #include <backend/platforms/VulkanPlatform.h>
 
+#include <utils/compiler.h> // UTILS_FALLTHROUGH
 #include <utils/Panic.h>    // ASSERT_POSTCONDITION
 
 using namespace bluevk;
@@ -89,8 +90,9 @@ BitmaskGroup fromBackendLayout(DescriptorSetLayout const& layout) {
                 }
                 break;
             }
-            // TODO: properly handle external sampler
             case DescriptorType::SAMPLER_EXTERNAL:
+                fromStageFlags(binding.stageFlags, binding.binding, mask.externalSampler);
+                UTILS_FALLTHROUGH;
             case DescriptorType::SAMPLER: {
                 fromStageFlags(binding.stageFlags, binding.binding, mask.sampler);
                 break;
@@ -147,11 +149,18 @@ void VulkanDescriptorSet::acquire(fvkmemory::resource_ptr<VulkanBufferObject> ob
     mResources.push_back(obj);
 }
 
-VulkanDescriptorSetLayout::VulkanDescriptorSetLayout(DescriptorSetLayout const& layout)
+VulkanDescriptorSetLayout::VulkanDescriptorSetLayout(DescriptorSetLayout&& layout,
+        VkDescriptorSetLayout vkLayout)
     : bitmask(fromBackendLayout(layout)),
-      count(Count::fromLayoutBitmask(bitmask)) {}
+      count(Count::fromLayoutBitmask(bitmask)),
+      mVkLayout(vkLayout) {}
 
-PushConstantDescription::PushConstantDescription(backend::Program const& program) noexcept {
+VulkanDescriptorSetLayout::Bitmask VulkanDescriptorSetLayout::Bitmask::fromLayoutDescription(
+        DescriptorSetLayout const& layout) {
+    return fromBackendLayout(layout);
+}
+
+PushConstantDescription::PushConstantDescription(backend::Program const& program) {
     mRangeCount = 0;
     for (auto stage : { ShaderStage::VERTEX, ShaderStage::FRAGMENT, ShaderStage::COMPUTE }) {
         auto const& constants = program.getPushConstants(stage);

filament/backend/src/vulkan/VulkanHandles.h

@@ -66,18 +66,23 @@ struct VulkanDescriptorSetLayout : public HwDescriptorSetLayout, fvkmemory::Reso
 
     // The bitmask representation of a set layout.
     struct Bitmask {
-        // TODO: better utiltize the space below and use bitset instead.
         fvkutils::UniformBufferBitmask ubo;         // 8 bytes
         fvkutils::UniformBufferBitmask dynamicUbo;  // 8 bytes
         fvkutils::SamplerBitmask sampler;           // 8 bytes
         fvkutils::InputAttachmentBitmask inputAttachment; // 8 bytes
 
+        // This is a subset of the sampler field.
+        fvkutils::SamplerBitmask externalSampler; // 8 bytes
+
         bool operator==(Bitmask const& right) const {
             return ubo == right.ubo && dynamicUbo == right.dynamicUbo && sampler == right.sampler &&
-                   inputAttachment == right.inputAttachment;
+                   inputAttachment == right.inputAttachment &&
+                   externalSampler == right.externalSampler;
         }
+
+        static Bitmask fromLayoutDescription(DescriptorSetLayout const& layout);
     };
-    static_assert(sizeof(Bitmask) == 32);
+    static_assert(sizeof(Bitmask) == 40);
 
     // This is a convenience struct to quickly check layout compatibility in terms of descriptor set
     // pools.
@@ -117,18 +122,32 @@ struct VulkanDescriptorSetLayout : public HwDescriptorSetLayout, fvkmemory::Reso
         }
     };
 
-    VulkanDescriptorSetLayout(DescriptorSetLayout const& layout);
+    VulkanDescriptorSetLayout(DescriptorSetLayout&& layout, VkDescriptorSetLayout vkLayout);
 
+    // Note that we don't destroy the vklayout. This is done by the layout cache.
     ~VulkanDescriptorSetLayout() = default;
 
-    VkDescriptorSetLayout getVkLayout() const { return mVkLayout; }
-    void setVkLayout(VkDescriptorSetLayout vklayout) { mVkLayout = vklayout; }
+    VkDescriptorSetLayout getVkLayout() const noexcept { return mVkLayout; }
+
+    VkDescriptorSetLayout getExternalSamplerVkLayout() const noexcept {
+        return mExternalSamplerVkLayout;
+    }
+
+    void setExternalSamplerVkLayout(VkDescriptorSetLayout vklayout) noexcept {
+        mExternalSamplerVkLayout = vklayout;
+    }
+
+    bool hasExternalSamplers() const noexcept { return bitmask.externalSampler.count() > 0; }
 
     Bitmask const bitmask;
     Count const count;
 
 private:
-    VkDescriptorSetLayout mVkLayout = VK_NULL_HANDLE;
+    // This is the layout without any immutable samplers.
+    VkDescriptorSetLayout const mVkLayout = VK_NULL_HANDLE;
+
+    // This is the layout with immutable samplers, and can be updated.
+    VkDescriptorSetLayout mExternalSamplerVkLayout = VK_NULL_HANDLE;
 };
 
 struct VulkanDescriptorSet : public HwDescriptorSet, fvkmemory::Resource {
@@ -137,19 +156,39 @@ public:
     // can use to repackage the vk handle.
     using OnRecycle = std::function<void(VulkanDescriptorSet*)>;
 
-    VulkanDescriptorSet(VkDescriptorSet rawSet,
+    VulkanDescriptorSet(
             fvkutils::UniformBufferBitmask const& dynamicUboMask,
             uint8_t uniqueDynamicUboCount,
-            OnRecycle&& onRecycleFn)
-        : vkSet(rawSet),
-          dynamicUboMask(dynamicUboMask),
+            OnRecycle&& onRecycleFn, VkDescriptorSet vkSet)
+        : dynamicUboMask(dynamicUboMask),
           uniqueDynamicUboCount(uniqueDynamicUboCount),
+          mVkSet(vkSet),
           mOnRecycleFn(std::move(onRecycleFn)) {}
 
+    // NOLINTNEXTLINE(bugprone-exception-escape)
     ~VulkanDescriptorSet() {
         if (mOnRecycleFn) {
             mOnRecycleFn(this);
         }
+        if (mOnRecycleExternalSamplerFn) {
+            mOnRecycleExternalSamplerFn(this);
+        }
+    }
+
+    VkDescriptorSet getVkSet() const noexcept {
+        return mVkSet;
+    }
+
+    VkDescriptorSet getExternalSamplerVkSet() const noexcept {
+        return mExternalSamplerVkSet;
+    }
+
+    void setExternalSamplerVkSet(VkDescriptorSet vkset, OnRecycle onRecycle) {
+        mExternalSamplerVkSet = vkset;
+        if (mOnRecycleExternalSamplerFn) {
+            mOnRecycleExternalSamplerFn(this);
+        }
+        mOnRecycleExternalSamplerFn = onRecycle;
     }
 
     void setOffsets(backend::DescriptorSetOffsetArray&& offsets) noexcept {
@@ -163,21 +202,24 @@ public:
     void acquire(fvkmemory::resource_ptr<VulkanTexture> texture);
     void acquire(fvkmemory::resource_ptr<VulkanBufferObject> buffer);
 
-    VkDescriptorSet const vkSet;
     fvkutils::UniformBufferBitmask const dynamicUboMask;
     uint8_t const uniqueDynamicUboCount;
 
 private:
+    VkDescriptorSet const mVkSet;
+    VkDescriptorSet mExternalSamplerVkSet = VK_NULL_HANDLE;
+
     backend::DescriptorSetOffsetArray mOffsets;
     std::vector<fvkmemory::resource_ptr<fvkmemory::Resource>> mResources;
     OnRecycle mOnRecycleFn;
+    OnRecycle mOnRecycleExternalSamplerFn;
 };
 
 using PushConstantNameArray = utils::FixedCapacityVector<char const*>;
 using PushConstantNameByStage = std::array<PushConstantNameArray, Program::SHADER_TYPE_COUNT>;
 
 struct PushConstantDescription {
-    explicit PushConstantDescription(backend::Program const& program) noexcept;
+    explicit PushConstantDescription(backend::Program const& program);
 
     VkPushConstantRange const* getVkRanges() const noexcept { return mRanges; }
     uint32_t getVkRangeCount() const noexcept { return mRangeCount; }

filament/backend/src/vulkan/VulkanPipelineCache.cpp

@@ -35,7 +35,12 @@ using namespace bluevk;
 namespace filament::backend {
 
 VulkanPipelineCache::VulkanPipelineCache(VkDevice device)
-        : mDevice(device) {}
+    : mDevice(device) {
+    VkPipelineCacheCreateInfo createInfo = {
+        .sType = VK_STRUCTURE_TYPE_PIPELINE_CACHE_CREATE_INFO,
+    };
+    bluevk::vkCreatePipelineCache(mDevice, &createInfo, VKALLOC, &mPipelineCache);
+}
 
 void VulkanPipelineCache::bindLayout(VkPipelineLayout layout) noexcept {
     mPipelineRequirements.layout = layout;
@@ -61,8 +66,12 @@ void VulkanPipelineCache::bindPipeline(VulkanCommandBuffer* commands) {
     // If an error occurred, allow higher levels to handle it gracefully.
     assert_invariant(cacheEntry != nullptr && "Failed to create/find pipeline");
 
-    mBoundPipeline = mPipelineRequirements;
-    vkCmdBindPipeline(cmdbuffer, VK_PIPELINE_BIND_POINT_GRAPHICS, cacheEntry->handle);
+
+    static PipelineEqual equal;
+    if (!equal(mBoundPipeline, mPipelineRequirements)) {
+        mBoundPipeline = mPipelineRequirements;
+        vkCmdBindPipeline(cmdbuffer, VK_PIPELINE_BIND_POINT_GRAPHICS, cacheEntry->handle);
+    }
 }
 
 VulkanPipelineCache::PipelineCacheEntry* VulkanPipelineCache::createPipeline() noexcept {
@@ -215,7 +224,7 @@ VulkanPipelineCache::PipelineCacheEntry* VulkanPipelineCache::createPipeline() n
     PipelineCacheEntry cacheEntry = {
         .lastUsed = mCurrentTime,
     };
-    VkResult error = vkCreateGraphicsPipelines(mDevice, VK_NULL_HANDLE, 1, &pipelineCreateInfo,
+    VkResult error = vkCreateGraphicsPipelines(mDevice, mPipelineCache, 1, &pipelineCreateInfo,
             VKALLOC, &cacheEntry.handle);
     assert_invariant(error == VK_SUCCESS);
     if (error != VK_SUCCESS) {
@@ -271,6 +280,8 @@ void VulkanPipelineCache::terminate() noexcept {
     }
     mPipelines.clear();
     mBoundPipeline = {};
+
+    vkDestroyPipelineCache(mDevice, mPipelineCache, VKALLOC);
 }
 
 void VulkanPipelineCache::gc() noexcept {

filament/backend/src/vulkan/VulkanPipelineCache.h

@@ -18,24 +18,18 @@
 #define TNT_FILAMENT_BACKEND_VULKANPIPELINECACHE_H
 
 #include "VulkanCommands.h"
-#include "VulkanMemory.h"
 
 #include <backend/DriverEnums.h>
 #include <backend/TargetBufferInfo.h>
 
-#include "backend/Program.h"
-
 #include <bluevk/BlueVK.h>
 
 #include <utils/bitset.h>
 #include <utils/compiler.h>
 #include <utils/Hash.h>
 
-#include <list>
 #include <tsl/robin_map.h>
 #include <type_traits>
-#include <vector>
-#include <unordered_map>
 
 namespace filament::backend {
 
@@ -204,6 +198,10 @@ private:
     // Immutable state.
     VkDevice mDevice = VK_NULL_HANDLE;
 
+    // Vuklan Driver pipeline cache handle. In the cases a pipeline has been  evicted by the `gc`,
+    // recreating the same pipeline is cheaper, helping with frame stalling.
+    VkPipelineCache mPipelineCache = VK_NULL_HANDLE;
+
     // Current requirements for the pipeline layout, pipeline, and descriptor sets.
     PipelineKey mPipelineRequirements = {};
 

filament/backend/src/vulkan/VulkanReadPixels.cpp

@@ -335,7 +335,7 @@ void VulkanReadPixels::run(fvkmemory::resource_ptr<VulkanRenderTarget> srcTarget
     mTaskHandler->post(std::move(waitFenceFunc), std::move(cleanPbdFunc));
 }
 
-void VulkanReadPixels::runUntilComplete() noexcept {
+void VulkanReadPixels::runUntilComplete() {
     if (!mTaskHandler) {
         return;
     }

filament/backend/src/vulkan/VulkanReadPixels.h

@@ -79,7 +79,7 @@ public:
             OnReadCompleteFunction const& readCompleteFunc);
 
     // This method will block until all of the in-flight requests are complete.
-    void runUntilComplete() noexcept;
+    void runUntilComplete();
 
 private:
     VkDevice mDevice = VK_NULL_HANDLE;

filament/backend/src/vulkan/VulkanSamplerCache.cpp

@@ -14,7 +14,9 @@
  * limitations under the License.
  */
 
-#include "vulkan/VulkanSamplerCache.h"
+#include "VulkanSamplerCache.h"
+
+#include "VulkanConstants.h"
 #include "vulkan/utils/Conversion.h"
 
 #include <utils/Panic.h>
@@ -26,41 +28,48 @@ namespace filament::backend {
 VulkanSamplerCache::VulkanSamplerCache(VkDevice device)
     : mDevice(device) {}
 
-VkSampler VulkanSamplerCache::getSampler(SamplerParams params) noexcept {
+VkSampler VulkanSamplerCache::getSampler(Params params) {
     auto iter = mCache.find(params);
     if (UTILS_LIKELY(iter != mCache.end())) {
         return iter->second;
     }
-    VkSamplerCreateInfo samplerInfo {
+    VkSamplerYcbcrConversionInfo ycbcrConversion = {
+        .sType = VK_STRUCTURE_TYPE_SAMPLER_YCBCR_CONVERSION_INFO,
+        .conversion = params.conversion,
+    };
+
+    auto const& samplerParams = params.sampler;
+    VkSamplerCreateInfo samplerInfo{
         .sType = VK_STRUCTURE_TYPE_SAMPLER_CREATE_INFO,
-        .magFilter = fvkutils::getFilter(params.filterMag),
-        .minFilter = fvkutils::getFilter(params.filterMin),
-        .mipmapMode = fvkutils::getMipmapMode(params.filterMin),
-        .addressModeU = fvkutils::getWrapMode(params.wrapS),
-        .addressModeV = fvkutils::getWrapMode(params.wrapT),
-        .addressModeW = fvkutils::getWrapMode(params.wrapR),
-        .anisotropyEnable = params.anisotropyLog2 == 0 ? VK_FALSE : VK_TRUE,
-        .maxAnisotropy = (float)(1u << params.anisotropyLog2),
-        .compareEnable = fvkutils::getCompareEnable(params.compareMode),
-        .compareOp = fvkutils::getCompareOp(params.compareFunc),
+        .pNext = params.conversion != VK_NULL_HANDLE ? &ycbcrConversion : VK_NULL_HANDLE,
+        .magFilter = fvkutils::getFilter(samplerParams.filterMag),
+        .minFilter = fvkutils::getFilter(samplerParams.filterMin),
+        .mipmapMode = fvkutils::getMipmapMode(samplerParams.filterMin),
+        .addressModeU = fvkutils::getWrapMode(samplerParams.wrapS),
+        .addressModeV = fvkutils::getWrapMode(samplerParams.wrapT),
+        .addressModeW = fvkutils::getWrapMode(samplerParams.wrapR),
+        .anisotropyEnable = samplerParams.anisotropyLog2 == 0 ? VK_FALSE : VK_TRUE,
+        .maxAnisotropy = (float) (1u << samplerParams.anisotropyLog2),
+        .compareEnable = fvkutils::getCompareEnable(samplerParams.compareMode),
+        .compareOp = fvkutils::getCompareOp(samplerParams.compareFunc),
         .minLod = 0.0f,
-        .maxLod = fvkutils::getMaxLod(params.filterMin),
+        .maxLod = fvkutils::getMaxLod(samplerParams.filterMin),
         .borderColor = VK_BORDER_COLOR_INT_OPAQUE_BLACK,
-        .unnormalizedCoordinates = VK_FALSE
+        .unnormalizedCoordinates = VK_FALSE,
     };
     VkSampler sampler;
     VkResult result = vkCreateSampler(mDevice, &samplerInfo, VKALLOC, &sampler);
     FILAMENT_CHECK_POSTCONDITION(result == VK_SUCCESS) << "Unable to create sampler."
                                                        << " error=" << static_cast<int32_t>(result);
-    mCache.insert({params, sampler});
+    mCache.insert({ params, sampler });
     return sampler;
 }
 
 void VulkanSamplerCache::terminate() noexcept {
-    for (auto pair : mCache) {
+    for (auto pair: mCache) {
         vkDestroySampler(mDevice, pair.second, VKALLOC);
     }
     mCache.clear();
 }
 
-} // namespace filament::backend
+}// namespace filament::backend

filament/backend/src/vulkan/VulkanSamplerCache.h

@@ -17,8 +17,11 @@
 #ifndef TNT_FILAMENT_BACKEND_VULKANSAMPLERCACHE_H
 #define TNT_FILAMENT_BACKEND_VULKANSAMPLERCACHE_H
 
-#include "VulkanContext.h"
+#include <backend/DriverEnums.h>
 
+#include <utils/Hash.h>
+
+#include <bluevk/BlueVK.h>
 #include <tsl/robin_map.h>
 
 namespace filament::backend {
@@ -26,12 +29,28 @@ namespace filament::backend {
 // Simple manager for VkSampler objects.
 class VulkanSamplerCache {
 public:
+    struct Params {
+        SamplerParams sampler = {};
+        uint32_t padding = 0;
+        VkSamplerYcbcrConversion conversion = VK_NULL_HANDLE;
+    };
+
+    static_assert(sizeof(Params) == 16);
+
     explicit VulkanSamplerCache(VkDevice device);
-    VkSampler getSampler(SamplerParams params) noexcept;
+    VkSampler getSampler(Params params);
     void terminate() noexcept;
 private:
     VkDevice mDevice;
-    tsl::robin_map<SamplerParams, VkSampler, SamplerParams::Hasher, SamplerParams::EqualTo> mCache;
+
+    struct SamplerEqualTo {
+        bool operator()(Params lhs, Params rhs) const noexcept {
+            SamplerParams::EqualTo equal;
+            return equal(lhs.sampler, rhs.sampler) && lhs.conversion == rhs.conversion;
+        }
+    };
+    using SamplerHashFn = utils::hash::MurmurHashFn<Params>;
+    tsl::robin_map<Params, VkSampler, SamplerHashFn, SamplerEqualTo> mCache;
 };
 
 } // namespace filament::backend

filament/backend/src/vulkan/VulkanStagePool.cpp

@@ -24,7 +24,7 @@
 
 #include <utils/Panic.h>
 
-static constexpr uint32_t TIME_BEFORE_EVICTION = FVK_MAX_COMMAND_BUFFERS;
+static constexpr uint32_t TIME_BEFORE_EVICTION = 3;
 
 namespace filament::backend {
 
@@ -39,7 +39,7 @@ VulkanStage const* VulkanStagePool::acquireStage(uint32_t numBytes) {
         auto stage = iter->second;
         mFreeStages.erase(iter);
         stage->lastAccessed = mCurrentFrame;
-        mUsedStages.insert(stage);
+        mUsedStages.push_back(stage);
         return stage;
     }
     // We were not able to find a sufficiently large stage, so create a new one.
@@ -51,7 +51,7 @@ VulkanStage const* VulkanStagePool::acquireStage(uint32_t numBytes) {
     });
 
     // Create the VkBuffer.
-    mUsedStages.insert(stage);
+    mUsedStages.push_back(stage);
     VkBufferCreateInfo bufferInfo {
         .sType = VK_STRUCTURE_TYPE_BUFFER_CREATE_INFO,
         .size = numBytes,
@@ -77,7 +77,7 @@ VulkanStageImage const* VulkanStagePool::acquireImage(PixelDataFormat format, Pi
         if (image->format == vkformat && image->width == width && image->height == height) {
             mFreeImages.erase(image);
             image->lastAccessed = mCurrentFrame;
-            mUsedImages.insert(image);
+            mUsedImages.push_back(image);
             return image;
         }
     }
@@ -89,7 +89,7 @@ VulkanStageImage const* VulkanStagePool::acquireImage(PixelDataFormat format, Pi
         .lastAccessed = mCurrentFrame,
     });
 
-    mUsedImages.insert(image);
+    mUsedImages.push_back(image);
 
     const VkImageCreateInfo imageInfo = {
         .sType = VK_STRUCTURE_TYPE_IMAGE_CREATE_INFO,
@@ -161,7 +161,7 @@ void VulkanStagePool::gc() noexcept {
             stage->lastAccessed = mCurrentFrame;
             mFreeStages.insert(std::make_pair(stage->capacity, stage));
         } else {
-            mUsedStages.insert(stage);
+            mUsedStages.push_back(stage);
         }
     }
 
@@ -185,7 +185,7 @@ void VulkanStagePool::gc() noexcept {
             image->lastAccessed = mCurrentFrame;
             mFreeImages.insert(image);
         } else {
-            mUsedImages.insert(image);
+            mUsedImages.push_back(image);
         }
     }
     FVK_SYSTRACE_END();

filament/backend/src/vulkan/VulkanStagePool.h

@@ -22,6 +22,7 @@
 
 #include <map>
 #include <unordered_set>
+#include <vector>
 
 namespace filament::backend {
 
@@ -73,10 +74,10 @@ private:
     std::multimap<uint32_t, VulkanStage const*> mFreeStages;
 
     // Simple unordered set for stashing a list of in-use stages that can be reclaimed later.
-    std::unordered_set<VulkanStage const*> mUsedStages;
+    std::vector<VulkanStage const*> mUsedStages;
 
     std::unordered_set<VulkanStageImage const*> mFreeImages;
-    std::unordered_set<VulkanStageImage const*> mUsedImages;
+    std::vector<VulkanStageImage const*> mUsedImages;
 
     // Store the current "time" (really just a frame count) and LRU eviction parameters.
     uint64_t mCurrentFrame = 0;

filament/backend/src/vulkan/VulkanSwapChain.cpp

@@ -32,6 +32,7 @@ VulkanSwapChain::VulkanSwapChain(VulkanPlatform* platform, VulkanContext const&
         VulkanCommands* commands, VulkanStagePool& stagePool, void* nativeWindow, uint64_t flags,
         VkExtent2D extent)
     : mPlatform(platform),
+      mContext(context),
       mResourceManager(resourceManager),
       mCommands(commands),
       mAllocator(allocator),
@@ -77,16 +78,16 @@ void VulkanSwapChain::update() {
     }
     for (auto const color: bundle.colors) {
         auto colorTexture = fvkmemory::resource_ptr<VulkanTexture>::construct(mResourceManager,
-                device, mAllocator, mResourceManager, mCommands, color, VK_NULL_HANDLE,
-                bundle.colorFormat, 1, bundle.extent.width, bundle.extent.height, bundle.layerCount, colorUsage,
-                mStagePool);
+                mContext, device, mAllocator, mResourceManager, mCommands, color, VK_NULL_HANDLE,
+                bundle.colorFormat, VK_NULL_HANDLE /*ycrcb */, 1, bundle.extent.width,
+                bundle.extent.height, bundle.layerCount, colorUsage, mStagePool);
         mColors.push_back(colorTexture);
     }
 
-    mDepth = fvkmemory::resource_ptr<VulkanTexture>::construct(mResourceManager, device,
-        mAllocator, mResourceManager, mCommands, bundle.depth, VK_NULL_HANDLE,
-        bundle.depthFormat, 1, bundle.extent.width, bundle.extent.height, bundle.layerCount, depthUsage,
-        mStagePool);
+    mDepth = fvkmemory::resource_ptr<VulkanTexture>::construct(mResourceManager, mContext, device,
+            mAllocator, mResourceManager, mCommands, bundle.depth, VK_NULL_HANDLE,
+            bundle.depthFormat, VK_NULL_HANDLE /*ycrcb */, 1, bundle.extent.width,
+            bundle.extent.height, bundle.layerCount, depthUsage, mStagePool);
 
     mExtent = bundle.extent;
     mLayerCount = bundle.layerCount;
@@ -107,11 +108,6 @@ void VulkanSwapChain::present() {
 
     mCommands->flush();
 
-    // call the image ready wait function
-    if (mExplicitImageReadyWait != nullptr) {
-        mExplicitImageReadyWait(swapChain);
-    }
-
     // We only present if it is not headless. No-op for headless.
     if (!mHeadless) {
         VkSemaphore const finishedDrawing = mCommands->acquireFinishedSignal();
@@ -145,7 +141,6 @@ void VulkanSwapChain::acquire(bool& resized) {
     VulkanPlatform::ImageSyncData imageSyncData;
     VkResult const result = mPlatform->acquire(swapChain, &imageSyncData);
     mCurrentSwapIndex = imageSyncData.imageIndex;
-    mExplicitImageReadyWait = imageSyncData.explicitImageReadyWait;
     FILAMENT_CHECK_POSTCONDITION(result == VK_SUCCESS || result == VK_SUBOPTIMAL_KHR)
             << "Cannot acquire in swapchain. error=" << static_cast<int32_t>(result);
     if (imageSyncData.imageReadySemaphore != VK_NULL_HANDLE) {