Merge branch 'rc/1.51.1' into release

This PR adds a new `pause()` option to the `Engine` `Builder` and a new function
`setPaused()` to the `Engine`. While paused, the rendering thread will pause
indefinitely for commands as if none are available. As soon as the rendering
thread is unpaused, the commands are immediately executed.

.github/actions/android-continuous/action.yml

@@ -1,17 +0,0 @@
-name: 'Android Continuous'
-inputs:
-  build-abi:
-    description: 'The target platform ABI'
-    required: true
-    default: 'armeabi-v7a'
-runs:
-  using: "composite"
-  steps:
-    - uses: actions/setup-java@v3
-      with:
-        distribution: 'temurin'
-        java-version: '17'
-    - name: Run build script
-      run: |
-        cd build/android && printf "y" | ./build.sh continuous ${{ inputs.build-abi }}
-      shell: bash

.github/actions/ubuntu-apt-add-src/action.yml

@@ -1,9 +0,0 @@
-name: 'ubuntu apt add deb-src'
-runs:
-  using: "composite"
-  steps:
-    - name: "ubuntu apt add deb-src"
-      run: |
-          echo "deb-src http://archive.ubuntu.com/ubuntu jammy main restricted universe" | sudo tee /etc/apt/sources.list.d/my.list
-          sudo apt-get update
-      shell: bash

.github/workflows/android-continuous.yml

@@ -10,13 +10,30 @@ on:
 jobs:
   build-android:
     name: build-android
-    # We intentially use a larger runner here to enable larger disk space
-    # (standard linux runner will fail on disk space and faster build time).
-    runs-on: ubuntu-22.04-32core
+    runs-on: macos-14
 
     steps:
-      - uses: actions/checkout@v4.1.6
-      - name: Run Android Continuous
-        uses: ./.github/actions/android-continuous
+      - uses: actions/checkout@v3.3.0
+      - uses: actions/setup-java@v3
         with:
-          build-abi: armeabi-v7a,arm64-v8a,x86_64
+          distribution: 'temurin'
+          java-version: '17'
+      - name: Run build script
+        run: |
+          cd build/android && printf "y" | ./build.sh continuous
+      - uses: actions/upload-artifact@v1.0.0
+        with:
+          name: filament-android
+          path: out/filament-android-release.aar
+      - uses: actions/upload-artifact@v1.0.0
+        with:
+          name: filamat-android-full
+          path: out/filamat-android-release.aar
+      - uses: actions/upload-artifact@v1.0.0
+        with:
+          name: gltfio-android-release
+          path: out/gltfio-android-release.aar
+      - uses: actions/upload-artifact@v1.0.0
+        with:
+          name: filament-utils-android-release
+          path: out/filament-utils-android-release.aar

.github/workflows/ios-continuous.yml

@@ -10,14 +10,14 @@ on:
 jobs:
   build-ios:
     name: build-ios
-    runs-on: macos-14-xlarge
+    runs-on: macos-14
 
     steps:
-      - uses: actions/checkout@v4.1.6
+      - uses: actions/checkout@v3.3.0
       - name: Run build script
         run: |
           cd build/ios && printf "y" | ./build.sh continuous
-      - uses: actions/upload-artifact@v4
+      - uses: actions/upload-artifact@v1.0.0
         with:
           name: filament-ios
           path: out/filament-release-ios.tgz

.github/workflows/linux-continuous.yml

@@ -10,14 +10,14 @@ on:
 jobs:
   build-linux:
     name: build-linux
-    runs-on: ubuntu-22.04-16core
+    runs-on: ubuntu-22.04
 
     steps:
-      - uses: actions/checkout@v4.1.6
+      - uses: actions/checkout@v3.3.0
       - name: Run build script
         run: |
           cd build/linux && printf "y" | ./build.sh continuous
-      - uses: actions/upload-artifact@v4
+      - uses: actions/upload-artifact@v1.0.0
         with:
           name: filament-linux
           path: out/filament-release-linux.tgz

.github/workflows/mac-continuous.yml

@@ -10,14 +10,14 @@ on:
 jobs:
   build-mac:
     name: build-mac
-    runs-on: macos-14-xlarge
+    runs-on: macos-14
 
     steps:
-      - uses: actions/checkout@v4.1.6
+      - uses: actions/checkout@v3.3.0
       - name: Run build script
         run: |
           cd build/mac && printf "y" | ./build.sh continuous
-      - uses: actions/upload-artifact@v4
+      - uses: actions/upload-artifact@v1.0.0
         with:
           name: filament-mac
           path: out/filament-release-darwin.tgz

.github/workflows/npm-deploy.yml

@@ -13,7 +13,7 @@ jobs:
     name: npm-deploy
     runs-on: macos-14
     steps:
-      - uses: actions/checkout@v4.1.6
+      - uses: actions/checkout@v3.3.0
         with:
           ref: ${{ github.event.inputs.release_tag }}
       # Setup .npmrc file to publish to npm

.github/workflows/presubmit.yml

@@ -15,10 +15,10 @@ jobs:
 
     strategy:
       matrix:
-        os: [macos-14-xlarge, ubuntu-22.04-16core]
+        os: [macos-14, ubuntu-22.04]
 
     steps:
-      - uses: actions/checkout@v4.1.6
+      - uses: actions/checkout@v3.3.0
       - name: Run build script
         run: |
           WORKFLOW_OS=`echo \`uname\` | sed "s/Darwin/mac/" | tr [:upper:] [:lower:]`
@@ -29,10 +29,10 @@ jobs:
 
   build-windows:
     name: build-windows
-    runs-on: win-2019-16core
+    runs-on: windows-2019
 
     steps:
-      - uses: actions/checkout@v4.1.6
+      - uses: actions/checkout@v3.3.0
       - name: Run build script
         run: |
           build\windows\build-github.bat presubmit
@@ -40,26 +40,24 @@ jobs:
 
   build-android:
     name: build-android
-    runs-on: ubuntu-22.04-16core
+    runs-on: macos-14
 
     steps:
-      - uses: actions/checkout@v4.1.6
+      - uses: actions/checkout@v3.3.0
       - uses: actions/setup-java@v3
         with:
           distribution: 'temurin'
           java-version: '17'
       - name: Run build script
-        # Only build 1 64 bit target during presubmit to cut down build times during presubmit
-        # Continuous builds will build everything
         run: |
-          cd build/android && printf "y" | ./build.sh presubmit arm64-v8a
+          cd build/android && printf "y" | ./build.sh presubmit
 
   build-ios:
     name: build-iOS
-    runs-on: macos-14-xlarge
+    runs-on: macos-14
 
     steps:
-      - uses: actions/checkout@v4.1.6
+      - uses: actions/checkout@v3.3.0
       - name: Run build script
         run: |
           cd build/ios && printf "y" | ./build.sh presubmit
@@ -69,25 +67,10 @@ jobs:
 
   build-web:
     name: build-web
-    runs-on: ubuntu-22.04-16core
+    runs-on: macos-14
 
     steps:
-      - uses: actions/checkout@v4.1.6
+      - uses: actions/checkout@v3.3.0
       - name: Run build script
         run: |
           cd build/web && printf "y" | ./build.sh presubmit
-
-  test-renderdiff:
-    name: test-renderdiff
-    runs-on: ubuntu-22.04-32core
-
-    steps:
-      - uses: actions/checkout@v4.1.6
-      - uses: ./.github/actions/ubuntu-apt-add-src
-      - name: Run script
-        run: |
-          source ./build/linux/ci-common.sh && bash test/renderdiff_tests.sh
-      - uses: actions/upload-artifact@v4
-        with:
-          name: presubmit-renderdiff-result
-          path: ./out/renderdiff_tests

.github/workflows/release.yml

@@ -31,7 +31,7 @@ jobs:
 
     strategy:
       matrix:
-        os: [macos-14-xlarge, ubuntu-22.04-32core]
+        os: [macos-14, ubuntu-22.04]
 
     steps:
       - name: Decide Git ref
@@ -41,7 +41,7 @@ jobs:
           TAG=${REF##*/}
           echo "ref=${REF}" >> $GITHUB_OUTPUT
           echo "tag=${TAG}" >> $GITHUB_OUTPUT
-      - uses: actions/checkout@v4.1.6
+      - uses: actions/checkout@v3.3.0
         with:
           ref: ${{ steps.git_ref.outputs.ref }}
       - name: Run build script
@@ -65,7 +65,7 @@ jobs:
 
   build-web:
     name: build-web
-    runs-on: ubuntu-22.04-16core
+    runs-on: macos-14
     if: github.event_name == 'release' || github.event.inputs.platform == 'web'
 
     steps:
@@ -76,7 +76,7 @@ jobs:
           TAG=${REF##*/}
           echo "ref=${REF}" >> $GITHUB_OUTPUT
           echo "tag=${TAG}" >> $GITHUB_OUTPUT
-      - uses: actions/checkout@v4.1.6
+      - uses: actions/checkout@v3.3.0
         with:
           ref: ${{ steps.git_ref.outputs.ref }}
       - name: Run build script
@@ -98,7 +98,7 @@ jobs:
 
   build-android:
     name: build-android
-    runs-on: ubuntu-22.04-16core
+    runs-on: macos-14
     if: github.event_name == 'release' || github.event.inputs.platform == 'android'
 
     steps:
@@ -109,7 +109,7 @@ jobs:
           TAG=${REF##*/}
           echo "ref=${REF}" >> $GITHUB_OUTPUT
           echo "tag=${TAG}" >> $GITHUB_OUTPUT
-      - uses: actions/checkout@v4.1.6
+      - uses: actions/checkout@v3.3.0
         with:
           ref: ${{ steps.git_ref.outputs.ref }}
       - uses: actions/setup-java@v3
@@ -120,7 +120,7 @@ jobs:
         env:
           TAG: ${{ steps.git_ref.outputs.tag }}
         run: |
-          cd build/android && printf "y" | ./build.sh release armeabi-v7a,arm64-v8a,x86,x86_64
+          cd build/android && printf "y" | ./build.sh release
           cd ../..
           mv out/filament-android-release.aar out/filament-${TAG}-android.aar
           mv out/filamat-android-release.aar out/filamat-${TAG}-android.aar
@@ -152,7 +152,7 @@ jobs:
 
   build-ios:
     name: build-ios
-    runs-on: macos-14-xlarge
+    runs-on: macos-14
     if: github.event_name == 'release' || github.event.inputs.platform == 'ios'
 
     steps:
@@ -163,7 +163,7 @@ jobs:
           TAG=${REF##*/}
           echo "ref=${REF}" >> $GITHUB_OUTPUT
           echo "tag=${TAG}" >> $GITHUB_OUTPUT
-      - uses: actions/checkout@v4.1.6
+      - uses: actions/checkout@v3.3.0
         with:
           ref: ${{ steps.git_ref.outputs.ref }}
       - name: Run build script
@@ -185,7 +185,7 @@ jobs:
 
   build-windows:
     name: build-windows
-    runs-on: windows-2019-32core
+    runs-on: windows-2019
     if: github.event_name == 'release' || github.event.inputs.platform == 'windows'
 
     steps:
@@ -197,7 +197,7 @@ jobs:
           echo "ref=${REF}" >> $GITHUB_OUTPUT
           echo "tag=${TAG}" >> $GITHUB_OUTPUT
         shell: bash
-      - uses: actions/checkout@v4.1.6
+      - uses: actions/checkout@v3.3.0
         with:
           ref: ${{ steps.git_ref.outputs.ref }}
       - name: Run build script
@@ -205,7 +205,6 @@ jobs:
           TAG: ${{ steps.git_ref.outputs.tag }}
         run: |
           build\windows\build-github.bat release
-          echo on
           move out\filament-windows.tgz out\filament-%TAG%-windows.tgz
         shell: cmd
       - uses: actions/github-script@v6

.github/workflows/web-continuous.yml

@@ -10,14 +10,14 @@ on:
 jobs:
   build-web:
     name: build-web
-    runs-on: ubuntu-22.04-16core
+    runs-on: macos-14
 
     steps:
-      - uses: actions/checkout@v4.1.6
+      - uses: actions/checkout@v3.3.0
       - name: Run build script
         run: |
           cd build/web && printf "y" | ./build.sh continuous
-      - uses: actions/upload-artifact@v4
+      - uses: actions/upload-artifact@v1.0.0
         with:
           name: filament-web
           path: out/filament-release-web.tgz

.github/workflows/windows-continuous.yml

@@ -10,15 +10,15 @@ on:
 jobs:
   build-windows:
     name: build-windows
-    runs-on: windows-2019-32core
+    runs-on: windows-2019
 
     steps:
-      - uses: actions/checkout@v4.1.6
+      - uses: actions/checkout@v3.3.0
       - name: Run build script
         run: |
           build\windows\build-github.bat continuous
         shell: cmd
-      - uses: actions/upload-artifact@v4
+      - uses: actions/upload-artifact@v1.0.0
         with:
           name: filament-windows
           path: out/filament-windows.tgz

BUILDING.md

@@ -73,6 +73,7 @@ The following CMake options are boolean options specific to Filament:
 - `FILAMENT_SUPPORTS_VULKAN`:      Include the Vulkan backend
 - `FILAMENT_INSTALL_BACKEND_TEST`: Install the backend test library so it can be consumed on iOS
 - `FILAMENT_USE_EXTERNAL_GLES3`:   Experimental: Compile Filament against OpenGL ES 3
+- `FILAMENT_USE_SWIFTSHADER`:      Compile Filament against SwiftShader
 - `FILAMENT_SKIP_SAMPLES`:         Don't build sample apps
 
 To turn an option on or off:
@@ -425,7 +426,7 @@ value is the desired roughness between 0 and 1.
 
 ## Generating C++ documentation
 
-To generate the documentation you must first install `doxygen` and `graphviz`, then run the
+To generate the documentation you must first install `doxygen` and `graphviz`, then run the 
 following commands:
 
 ```shell
@@ -435,62 +436,32 @@ doxygen docs/doxygen/filament.doxygen
 
 Finally simply open `docs/html/index.html` in your web browser.
 
-## Software Rasterization
+## SwiftShader
 
-We have tested swiftshader and Mesa for software rasterization on the Vulkan/GL backends.
-
-To use this for Vulkan, please first make sure that the [Vulkan SDK](https://www.lunarg.com/vulkan-sdk/) is
-installed on your machine. If you are doing a manual installation of the SDK on Linux, you will have
-to source `setup-env.sh` in the SDK's root folder to make sure the Vulkan loader is the first lib loaded.
-
-### Swiftshader (Vulkan) [tested on macOS and Linux]
-
-First, build SwiftShader
+To try out Filament's Vulkan support with SwiftShader, first build SwiftShader and set the
+`SWIFTSHADER_LD_LIBRARY_PATH` variable to the folder that contains `libvk_swiftshader.dylib`:
 
 ```shell
 git clone https://github.com/google/swiftshader.git
 cd swiftshader/build
 cmake .. &&  make -j
+export SWIFTSHADER_LD_LIBRARY_PATH=`pwd`
 ```
 
-and then set `VK_ICD_FILENAMES` to the ICD json produced in the build. For example,
-```shell
-export VK_ICD_FILENAMES=/Users/user/swiftshader/build/Darwin/vk_swiftshader_icd.json
-```
+Next, go to your Filament repo and use the [easy build](#easy-build) script with `-t`.
 
-Build and run Filament as usual and specify the Vulkan backend when creating the Engine.
+## SwiftShader for CI
 
-### Mesa's LLVMPipe (GL) and Lavapipe (Vulkan) [tested on Linux]
-
-We will only cover steps that build Mesa from source. The official documentation of Mesa mentioned
-that in general precompiled libraries [are **not** made available](https://docs.mesa3d.org/precompiled.html).
-
-Download the repo and make sure you have the build depedencies. For example (assuming an Ubuntu/Debian distro),
-```shell
-git clone https://gitlab.freedesktop.org/mesa/mesa.git
-sudo apt-get build-dep mesa
-```
-
-To build both the GL and Vulkan rasterizers,
+Continuous testing turnaround can be quite slow if you need to build SwiftShader from scratch, so we
+provide an Ubuntu-based Docker image that has it already built. The Docker image also includes
+everything necessary for building Filament. You can fetch and run the image as follows:
 
 ```shell
-cd mesa
-mkdir -p out
-meson setup builddir/ -Dprefix=$(pwd)/out -Dglx=xlib -Dgallium-drivers=swrast -Dvulkan-drivers=swrast
-meson install -C builddir/
+docker pull ghcr.io/filament-assets/swiftshader
+docker run -it ghcr.io/filament-assets/swiftshader
 ```
 
-For GL, we need to ensure that we load the GL lib from the mesa output directory.  For example, to run
-the debug `gltf_viewer`, we would execute
-```shell
-LD_LIBRARY_PATH=/Users/user/mesa/out/lib/x86_64-linux-gnu \
-    ./out/cmake-debug/samples/gltf_viewer -a opengl
-```
+To do more with the container, see the helper script at `build/swiftshader/test.sh`.
 
-For Vulkan, we need to set the path to the ICD json, which tells the loader where to find the driver
-library. To run `gltf_viewer`, we would execute
-```shell
-VK_ICD_FILENAMES=/Users/user/mesa/out/share/vulkan/icd.d/lvp_icd.x86_64.json \
-    ./out/cmake-debug/samples/gltf_viewer -a vulkan
-
-```
+If you are a team member, you can update the public image to the latest SwiftShader by
+following the instructions at the top of `build/swiftshader/Dockerfile`.

CMakeLists.txt

@@ -21,6 +21,8 @@ project(TNT)
 # ==================================================================================================
 option(FILAMENT_USE_EXTERNAL_GLES3 "Experimental: Compile Filament against OpenGL ES 3" OFF)
 
+option(FILAMENT_USE_SWIFTSHADER "Compile Filament against SwiftShader" OFF)
+
 option(FILAMENT_ENABLE_LTO "Enable link-time optimizations if supported by the compiler" OFF)
 
 option(FILAMENT_SKIP_SAMPLES "Don't build samples" OFF)
@@ -45,8 +47,6 @@ option(FILAMENT_ENABLE_FEATURE_LEVEL_0 "Enable Feature Level 0" ON)
 
 option(FILAMENT_ENABLE_MULTIVIEW "Enable multiview for Filament" OFF)
 
-option(FILAMENT_SUPPORTS_OSMESA "Enable OSMesa (headless GL context) for Filament" OFF)
-
 set(FILAMENT_NDK_VERSION "" CACHE STRING
     "Android NDK version or version prefix to be used when building for Android."
 )
@@ -71,14 +71,6 @@ set(FILAMENT_METAL_HANDLE_ARENA_SIZE_IN_MB "8" CACHE STRING
     "Size of the Metal handle arena, default 8."
 )
 
-set(FILAMENT_BACKEND_DEBUG_FLAG "" CACHE STRING
-    "A debug flag meant for enabling/disabling backend debugging paths"
-)
-
-set(FILAMENT_OSMESA_PATH "" CACHE STRING
-    "Path to the OSMesa header and lib"
-)
-
 # Enable exceptions by default in spirv-cross.
 set(SPIRV_CROSS_EXCEPTIONS_TO_ASSERTIONS OFF)
 
@@ -138,27 +130,22 @@ else()
 endif()
 
 if (LINUX)
-    if (NOT FILAMENT_OSMESA_PATH STREQUAL "")
-        if (NOT EXISTS ${FILAMENT_OSMESA_PATH}/)
-            message(FATAL_ERROR "Cannot find specified OSMesa build directory: ${FILAMENT_OSMESA_PATH}")
-        endif()
-        set(FILAMENT_SUPPORTS_OSMESA TRUE)
-    endif()
-
     if (FILAMENT_SUPPORTS_WAYLAND)
         add_definitions(-DFILAMENT_SUPPORTS_WAYLAND)
         set(FILAMENT_SUPPORTS_X11 FALSE)
     elseif (FILAMENT_SUPPORTS_EGL_ON_LINUX)
         add_definitions(-DFILAMENT_SUPPORTS_EGL_ON_LINUX)
         set(FILAMENT_SUPPORTS_X11 FALSE)
-    elseif (FILAMENT_SUPPORTS_OSMESA)
-        set(FILAMENT_SUPPORTS_X11 FALSE)
-        add_definitions(-DFILAMENT_SUPPORTS_OSMESA)
     else ()
         if (FILAMENT_SUPPORTS_XCB)
             add_definitions(-DFILAMENT_SUPPORTS_XCB)
         endif()
 
+        # Default Swiftshader build does not enable the xlib extension
+        if (FILAMENT_SUPPORTS_XLIB AND FILAMENT_USE_SWIFTSHADER)
+            set(FILAMENT_SUPPORTS_XLIB OFF)
+        endif()
+
         if (FILAMENT_SUPPORTS_XLIB)
             add_definitions(-DFILAMENT_SUPPORTS_XLIB)
         endif()
@@ -182,6 +169,15 @@ if (NOT ANDROID AND NOT WEBGL AND NOT IOS AND NOT FILAMENT_LINUX_IS_MOBILE)
     set(IS_HOST_PLATFORM TRUE)
 endif()
 
+if (IOS)
+    # Remove the headerpad_max_install_names linker flag on iOS. It causes warnings when linking
+    # executables with bitcode.
+    string(REPLACE "-Wl,-headerpad_max_install_names" "" CMAKE_C_LINK_FLAGS ${CMAKE_C_LINK_FLAGS})
+    string(REPLACE "-Wl,-headerpad_max_install_names" "" CMAKE_CXX_LINK_FLAGS ${CMAKE_CXX_LINK_FLAGS})
+    string(REPLACE "-Wl,-headerpad_max_install_names" "" CMAKE_SHARED_LIBRARY_CREATE_C_FLAGS ${CMAKE_SHARED_LIBRARY_CREATE_C_FLAGS})
+    string(REPLACE "-Wl,-headerpad_max_install_names" "" CMAKE_SHARED_LIBRARY_CREATE_CXX_FLAGS ${CMAKE_SHARED_LIBRARY_CREATE_CXX_FLAGS})
+endif()
+
 if (WIN32)
     # Link statically against c/c++ lib to avoid missing redistriburable such as
     # "VCRUNTIME140.dll not found. Try reinstalling the app.", but give users
@@ -336,6 +332,10 @@ if (FILAMENT_SUPPORTS_EGL_ON_LINUX)
   set(EGL TRUE)
 endif()
 
+if (FILAMENT_USE_SWIFTSHADER)
+    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -DFILAMENT_USE_SWIFTSHADER")
+endif()
+
 if (WIN32)
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -D_USE_MATH_DEFINES=1")
 endif()
@@ -389,9 +389,8 @@ endif()
 if (NOT MSVC AND NOT IOS)
     # Omitting stack frame pointers prevents the generation of readable stack traces in crash reports on iOS
     set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE} -fomit-frame-pointer")
-endif()
 
-if (NOT MSVC)
+    # These aren't compatible with -fembed-bitcode (and seem to have no effect on Apple platforms anyway)
     set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE} -ffunction-sections -fdata-sections")
 endif()
 
@@ -456,13 +455,8 @@ endif()
 if (NOT WEBGL)
     set(GC_SECTIONS "-Wl,--gc-sections")
 endif()
-
 set(B_SYMBOLIC_FUNCTIONS "-Wl,-Bsymbolic-functions")
 
-if (ANDROID)
-set(BINARY_ALIGNMENT "-Wl,-z,max-page-size=16384")
-endif()
-
 if (APPLE)
     set(GC_SECTIONS "-Wl,-dead_strip")
     set(B_SYMBOLIC_FUNCTIONS "")
@@ -476,7 +470,7 @@ if (APPLE)
 endif()
 
 set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} ${GC_SECTIONS}")
-set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} ${GC_SECTIONS} ${B_SYMBOLIC_FUNCTIONS} ${BINARY_ALIGNMENT}")
+set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} ${GC_SECTIONS} ${B_SYMBOLIC_FUNCTIONS}")
 
 if (WEBGL_PTHREADS)
     set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} -pthread")
@@ -540,15 +534,13 @@ else()
 endif()
 
 # This only affects the prebuilt shader files in gltfio and samples, not filament library.
-# The value can be either "instanced", "multiview", or "none"
-set(FILAMENT_SAMPLES_STEREO_TYPE "none" CACHE STRING
+# The value can be either "instanced" or "multiview".
+set(FILAMENT_SAMPLES_STEREO_TYPE "instanced" CACHE STRING
     "Stereoscopic type that shader files in gltfio and samples are built for."
 )
 string(TOLOWER "${FILAMENT_SAMPLES_STEREO_TYPE}" FILAMENT_SAMPLES_STEREO_TYPE)
-if (NOT FILAMENT_SAMPLES_STEREO_TYPE STREQUAL "instanced"
-    AND NOT FILAMENT_SAMPLES_STEREO_TYPE STREQUAL "multiview"
-    AND NOT FILAMENT_SAMPLES_STEREO_TYPE STREQUAL "none")
-    message(FATAL_ERROR "Invalid stereo type: \"${FILAMENT_SAMPLES_STEREO_TYPE}\" choose either \"instanced\",  \"multiview\", or \"none\" ")
+if (NOT FILAMENT_SAMPLES_STEREO_TYPE STREQUAL "instanced" AND NOT FILAMENT_SAMPLES_STEREO_TYPE STREQUAL "multiview")
+    message(FATAL_ERROR "Invalid stereo type: \"${FILAMENT_SAMPLES_STEREO_TYPE}\" choose either \"instanced\" or \"multiview\" ")
 endif ()
 
 # Compiling samples for multiview implies enabling multiview feature as well.
@@ -556,12 +548,6 @@ if (FILAMENT_SAMPLES_STEREO_TYPE STREQUAL "multiview")
     set(FILAMENT_ENABLE_MULTIVIEW ON)
 endif ()
 
-# Define backend flag for debug only
-if (CMAKE_BUILD_TYPE STREQUAL "Debug" AND NOT FILAMENT_BACKEND_DEBUG_FLAG STREQUAL "")
-    add_definitions(-DFILAMENT_BACKEND_DEBUG_FLAG=${FILAMENT_BACKEND_DEBUG_FLAG})
-    unset(FILAMENT_BACKEND_DEBUG_FLAG)
-endif()
-
 # ==================================================================================================
 # Material compilation flags
 # ==================================================================================================
@@ -690,6 +676,21 @@ else()
     set(IMPORT_EXECUTABLES ${FILAMENT}/${IMPORT_EXECUTABLES_DIR}/ImportExecutables-${CMAKE_BUILD_TYPE}.cmake)
 endif()
 
+# ==================================================================================================
+# Try to find Vulkan if the SDK is installed, otherwise fall back to the bundled version.
+# This needs to stay in our top-level CMakeLists because it sets up variables that are used by the
+# "bluevk" and "samples" targets.
+# ==================================================================================================
+
+if (FILAMENT_USE_SWIFTSHADER)
+    if (NOT FILAMENT_SUPPORTS_VULKAN)
+        message(ERROR "SwiftShader is only useful when Vulkan is enabled.")
+    endif()
+    find_library(SWIFTSHADER_VK NAMES vk_swiftshader HINTS "$ENV{SWIFTSHADER_LD_LIBRARY_PATH}")
+    message(STATUS "Found SwiftShader VK library in: ${SWIFTSHADER_VK}.")
+    add_definitions(-DFILAMENT_VKLIBRARY_PATH=\"${SWIFTSHADER_VK}\")
+endif()
+
 # ==================================================================================================
 # Common Functions
 # ==================================================================================================
@@ -751,6 +752,7 @@ add_subdirectory(${FILAMENT}/filament)
 add_subdirectory(${FILAMENT}/shaders)
 add_subdirectory(${EXTERNAL}/basisu/tnt)
 add_subdirectory(${EXTERNAL}/civetweb/tnt)
+add_subdirectory(${EXTERNAL}/hat-trie/tnt)
 add_subdirectory(${EXTERNAL}/imgui/tnt)
 add_subdirectory(${EXTERNAL}/robin-map/tnt)
 add_subdirectory(${EXTERNAL}/smol-v/tnt)
@@ -817,9 +819,6 @@ if (IS_HOST_PLATFORM)
     add_subdirectory(${TOOLS}/glslminifier)
     add_subdirectory(${TOOLS}/matc)
     add_subdirectory(${TOOLS}/matinfo)
-    if (NOT WIN32)  # matedit not yet supported on Windows
-        add_subdirectory(${TOOLS}/matedit)
-    endif()
     add_subdirectory(${TOOLS}/mipgen)
     add_subdirectory(${TOOLS}/normal-blending)
     add_subdirectory(${TOOLS}/resgen)

NEW_RELEASE_NOTES.md

@@ -7,4 +7,5 @@ for next branch cut* header.
 appropriate header in [RELEASE_NOTES.md](./RELEASE_NOTES.md).
 
 ## Release notes for next branch cut
-- vk: fix stage pool gc logic
+
+- engine: Add experimental APIs `Engine::builder::paused()` and `Engine::setPaused()`

README.md

@@ -31,7 +31,7 @@ repositories {
 }
 
 dependencies {
-    implementation 'com.google.android.filament:filament-android:1.56.0'
+    implementation 'com.google.android.filament:filament-android:1.51.1'
 }
 ```
 
@@ -51,9 +51,19 @@ 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', '~> 1.56.0'
+pod 'Filament', '~> 1.51.1'
 ```
 
+### Snapshots
+
+If you prefer to live on the edge, you can download a continuous build by following the following
+steps:
+
+1. Find the [commit](https://github.com/google/filament/commits/main) you're interested in.
+2. Click the green check mark under the commit message.
+3. Click on the _Details_ link for the platform you're interested in.
+4. On the top left click _Summary_, then in the _Artifacts_ section choose the desired artifact.
+
 ## Documentation
 
 - [Filament](https://google.github.io/filament/Filament.html), an in-depth explanation of
@@ -166,7 +176,6 @@ pod 'Filament', '~> 1.56.0'
   - [x] KHR_materials_unlit
   - [x] KHR_materials_variants
   - [x] KHR_materials_volume
-  - [x] KHR_materials_specular
   - [x] KHR_mesh_quantization
   - [x] KHR_texture_basisu
   - [x] KHR_texture_transform

RELEASE_NOTES.md

@@ -7,107 +7,6 @@ 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).
 
-## v1.56.1
-
-## v1.56.0
-
-- backend: descriptor layouts distinguish samplers and external samplers (b/376089915) [⚠️ **New Material Version**]
-
-## v1.55.1
-
-
-## v1.55.0
-- Add descriptor sets to describe shader resources. [⚠️ **New Material Version**]
-
-## v1.54.5
-
-
-## v1.54.4
-
-- Add support for multi-layered render target with array textures.
-
-## v1.54.3
-
-
-## v1.54.2
-
-- Add a `name` API to Filament objects for debugging handle use-after-free assertions
-
-## v1.54.1
-
-
-## v1.54.0
-
-- materials: add a new `stereoscopicType` material parameter. [⚠️ **New Material Version**]
-- Fix a crash when compiling shaders on IMG devices
-
-## v1.53.5
-
-- engine: Fix bug causing certain sampler parameters to not be applied correctly in GLES 2.0 and on
-  certain GLES 3.0 drivers.
-
-## v1.53.4
-
-
-## v1.53.3
-
-- Add drag and drop support for IBL files for desktop gltf_viewer.
-
-## v1.53.2
-
-
-## v1.53.1
-
-
-## v1.53.0
-
-- engine: fix skinning normals with large transforms (b/342459864) [⚠️ **New Material Version**]
-
-## v1.52.3
-
-
-## v1.52.2
-
-
-## v1.52.1
-
-- Add instructions for using Mesa for software rasterization
-
-## v1.51.9
-
-
-## v1.51.8
-
-- filagui: Fix regression which broke WebGL
-- Add a new Engine::Config setting to control preferred shader language
-- Add `getEyeIndex` vertex API
-- ios: Remove bitcode from iOS builds
-
-## v1.51.7
-
-- Add new matedit tool
-- filagui: Support rendering `GL_TEXTURE_EXTERNAL_OES` textures.
-- `setFrameScheduledCallback` now takes a `utils::Invocable`.
-- engine: Add `isPaused()`
-
-## v1.51.6
-
-- Add new matedit tool
-- filagui: Support rendering `GL_TEXTURE_EXTERNAL_OES` textures.
-
-## v1.51.5
-
-
-## v1.51.4
-
-
-## v1.51.3
-
-
-## v1.51.2
-
-- engine: Add experimental APIs `Engine::builder::paused()` and `Engine::setPaused()`
-
 ## v1.51.1
 
 
@@ -660,7 +559,7 @@ Instead, if you are authoring a PR for the main branch, add your release note to
 
 - engine: Binary size improvements.
 - engine: Add basic support for instanced renderables [**NEW API**].
-- engine: Fix, first imaged passed to `Stream::SetAcquiredImage` is ignored and leaked.
+- engine: Fix, first imaged passsed to `Stream::SetAcquiredImage` is ignored and leaked.
 - Vulkan: Robustness improvements.
 - Java: Fix, lookAt z axis negated.
 - gltfio: Be graceful when model has > 4 weights per vert.

android/build.gradle

@@ -83,12 +83,12 @@ buildscript {
         'minSdk': 21,
         'targetSdk': 34,
         'compileSdk': 34,
-        'kotlin': '2.0.21',
-        'kotlin_coroutines': '1.9.0',
-        'buildTools': '35.0.0',
-        'ndk': '27.0.11718014',
-        'androidx_core': '1.13.1',
-        'androidx_annotations': '1.9.0'
+        'kotlin': '1.9.21',
+        'kotlin_coroutines': '1.7.3',
+        'buildTools': '34.0.0',
+        'ndk': '26.1.10909125',
+        'androidx_core': '1.12.0',
+        'androidx_annotations': '1.7.0'
     ]
 
     ext.deps = [
@@ -104,7 +104,7 @@ buildscript {
     ]
 
     dependencies {
-        classpath 'com.android.tools.build:gradle:8.6.1'
+        classpath 'com.android.tools.build:gradle:8.2.0'
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:${versions.kotlin}"
     }
 

android/filamat-android/CMakeLists.txt

@@ -38,7 +38,6 @@ set(FILAMAT_INCLUDE_DIRS
 include_directories(${FILAMENT_DIR}/include)
 
 set(CMAKE_SHARED_LINKER_FLAGS_RELEASE "${CMAKE_SHARED_LINKER_FLAGS_RELEASE} -Wl,--version-script=${CMAKE_SOURCE_DIR}/libfilamat-jni.map")
-set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} -Wl,-z,max-page-size=16384")
 
 add_library(filamat-jni SHARED src/main/cpp/MaterialBuilder.cpp)
 target_include_directories(filamat-jni PRIVATE ${FILAMAT_INCLUDE_DIRS})

android/filament-android/CMakeLists.txt

@@ -59,7 +59,6 @@ endif()
 
 set(VERSION_SCRIPT "${CMAKE_CURRENT_SOURCE_DIR}/libfilament-jni.map")
 set(CMAKE_SHARED_LINKER_FLAGS_RELEASE "${CMAKE_SHARED_LINKER_FLAGS_RELEASE} -Wl,--version-script=${VERSION_SCRIPT}")
-set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} -Wl,-z,max-page-size=16384")
 
 add_library(filament-jni SHARED
     src/main/cpp/BufferObject.cpp

android/filament-android/src/main/cpp/Engine.cpp

@@ -342,21 +342,6 @@ Java_com_google_android_filament_Engine_nIsValidMaterial(JNIEnv*, jclass,
     return (jboolean)engine->isValid((Material*)nativeMaterial);
 }
 
-extern "C" JNIEXPORT jboolean JNICALL
-Java_com_google_android_filament_Engine_nIsValidMaterialInstance(JNIEnv*, jclass,
-        jlong nativeEngine, jlong nativeMaterial, jlong nativeMaterialInstance) {
-    Engine* engine = (Engine *)nativeEngine;
-    return (jboolean)engine->isValid((Material*)nativeMaterial,
-            (MaterialInstance*)nativeMaterialInstance);
-}
-
-extern "C" JNIEXPORT jboolean JNICALL
-        Java_com_google_android_filament_Engine_nIsValidExpensiveMaterialInstance(JNIEnv*, jclass,
-        jlong nativeEngine, jlong nativeMaterialInstance) {
-    Engine* engine = (Engine *)nativeEngine;
-    return (jboolean)engine->isValidExpensive((MaterialInstance*)nativeMaterialInstance);
-}
-
 extern "C" JNIEXPORT jboolean JNICALL
 Java_com_google_android_filament_Engine_nIsValidSkybox(JNIEnv*, jclass,
         jlong nativeEngine, jlong nativeSkybox) {
@@ -406,13 +391,6 @@ Java_com_google_android_filament_Engine_nFlush(JNIEnv*, jclass,
     engine->flush();
 }
 
-extern "C" JNIEXPORT jboolean JNICALL
-Java_com_google_android_filament_Engine_nIsPaused(JNIEnv*, jclass,
-        jlong nativeEngine) {
-    Engine* engine = (Engine*) nativeEngine;
-    return (jboolean)engine->isPaused();
-}
-
 extern "C" JNIEXPORT void JNICALL
 Java_com_google_android_filament_Engine_nSetPaused(JNIEnv*, jclass,
         jlong nativeEngine, jboolean paused) {
@@ -420,13 +398,6 @@ Java_com_google_android_filament_Engine_nSetPaused(JNIEnv*, jclass,
     engine->setPaused(paused);
 }
 
-extern "C" JNIEXPORT void JNICALL
-Java_com_google_android_filament_Engine_nUnprotected(JNIEnv*, jclass,
-        jlong nativeEngine, jboolean paused) {
-    Engine* engine = (Engine*) nativeEngine;
-    engine->unprotected();
-}
-
 // Managers...
 
 extern "C" JNIEXPORT jlong JNICALL
@@ -499,37 +470,6 @@ Java_com_google_android_filament_Engine_nGetActiveFeatureLevel(JNIEnv *, jclass,
     return (jint)engine->getActiveFeatureLevel();
 }
 
-extern "C"
-JNIEXPORT jboolean JNICALL
-Java_com_google_android_filament_Engine_nHasFeatureFlag(JNIEnv *env, jclass clazz,
-        jlong nativeEngine, jstring name_) {
-    Engine* engine = (Engine*) nativeEngine;
-    const char *name = env->GetStringUTFChars(name_, 0);
-    std::optional<bool> result = engine->getFeatureFlag(name);
-    env->ReleaseStringUTFChars(name_, name);
-    return result.has_value();
-}
-extern "C"
-JNIEXPORT jboolean JNICALL
-Java_com_google_android_filament_Engine_nSetFeatureFlag(JNIEnv *env, jclass clazz,
-        jlong nativeEngine, jstring name_, jboolean value) {
-    Engine* engine = (Engine*) nativeEngine;
-    const char *name = env->GetStringUTFChars(name_, 0);
-    jboolean result = engine->setFeatureFlag(name, (bool)value);
-    env->ReleaseStringUTFChars(name_, name);
-    return result;
-}
-extern "C"
-JNIEXPORT jboolean JNICALL
-Java_com_google_android_filament_Engine_nGetFeatureFlag(JNIEnv *env, jclass clazz,
-        jlong nativeEngine, jstring name_) {
-    Engine* engine = (Engine*) nativeEngine;
-    const char *name = env->GetStringUTFChars(name_, 0);
-    std::optional<bool> result = engine->getFeatureFlag(name);
-    env->ReleaseStringUTFChars(name_, name);
-    return result.value_or(false); // we should never fail here
-}
-
 extern "C" JNIEXPORT jlong JNICALL Java_com_google_android_filament_Engine_nCreateBuilder(JNIEnv*,
         jclass) {
     Engine::Builder* builder = new Engine::Builder{};
@@ -551,12 +491,11 @@ extern "C" JNIEXPORT void JNICALL Java_com_google_android_filament_Engine_nSetBu
 extern "C" JNIEXPORT void JNICALL Java_com_google_android_filament_Engine_nSetBuilderConfig(JNIEnv*,
         jclass, jlong nativeBuilder, jlong commandBufferSizeMB, jlong perRenderPassArenaSizeMB,
         jlong driverHandleArenaSizeMB, jlong minCommandBufferSizeMB, jlong perFrameCommandsSizeMB,
-        jlong jobSystemThreadCount, jboolean disableParallelShaderCompile,
+        jlong jobSystemThreadCount,
+        jlong textureUseAfterFreePoolSize, jboolean disableParallelShaderCompile,
         jint stereoscopicType, jlong stereoscopicEyeCount,
         jlong resourceAllocatorCacheSizeMB, jlong resourceAllocatorCacheMaxAge,
-        jboolean disableHandleUseAfterFreeCheck,
-        jint preferredShaderLanguage,
-        jboolean forceGLES2Context, jboolean assertNativeWindowIsValid) {
+        jboolean disableHandleUseAfterFreeCheck) {
     Engine::Builder* builder = (Engine::Builder*) nativeBuilder;
     Engine::Config config = {
             .commandBufferSizeMB = (uint32_t) commandBufferSizeMB,
@@ -565,15 +504,13 @@ extern "C" JNIEXPORT void JNICALL Java_com_google_android_filament_Engine_nSetBu
             .minCommandBufferSizeMB = (uint32_t) minCommandBufferSizeMB,
             .perFrameCommandsSizeMB = (uint32_t) perFrameCommandsSizeMB,
             .jobSystemThreadCount = (uint32_t) jobSystemThreadCount,
+            .textureUseAfterFreePoolSize = (uint32_t) textureUseAfterFreePoolSize,
             .disableParallelShaderCompile = (bool) disableParallelShaderCompile,
             .stereoscopicType = (Engine::StereoscopicType) stereoscopicType,
             .stereoscopicEyeCount = (uint8_t) stereoscopicEyeCount,
             .resourceAllocatorCacheSizeMB = (uint32_t) resourceAllocatorCacheSizeMB,
             .resourceAllocatorCacheMaxAge = (uint8_t) resourceAllocatorCacheMaxAge,
             .disableHandleUseAfterFreeCheck = (bool) disableHandleUseAfterFreeCheck,
-            .preferredShaderLanguage = (Engine::Config::ShaderLanguage) preferredShaderLanguage,
-            .forceGLES2Context = (bool) forceGLES2Context,
-            .assertNativeWindowIsValid = (bool) assertNativeWindowIsValid,
     };
     builder->config(&config);
 }
@@ -596,24 +533,8 @@ extern "C" JNIEXPORT void JNICALL Java_com_google_android_filament_Engine_nSetBu
     builder->paused((bool) paused);
 }
 
-extern "C"
-JNIEXPORT void JNICALL
-Java_com_google_android_filament_Engine_nSetBuilderFeature(JNIEnv *env, jclass clazz,
-        jlong nativeBuilder, jstring name_, jboolean value) {
-    Engine::Builder* builder = (Engine::Builder*) nativeBuilder;
-    const char *name = env->GetStringUTFChars(name_, 0);
-    builder->feature(name, (bool)value);
-    env->ReleaseStringUTFChars(name_, name);
-}
-
 extern "C" JNIEXPORT jlong JNICALL
 Java_com_google_android_filament_Engine_nBuilderBuild(JNIEnv*, jclass, jlong nativeBuilder) {
     Engine::Builder* builder = (Engine::Builder*) nativeBuilder;
     return (jlong) builder->build();
 }
-
-extern "C"
-JNIEXPORT jlong JNICALL
-Java_com_google_android_filament_Engine_getSteadyClockTimeNano(JNIEnv *env, jclass clazz) {
-    return (jlong)Engine::getSteadyClockTimeNano();
-}

android/filament-android/src/main/cpp/Material.cpp

@@ -25,17 +25,12 @@ using namespace filament;
 
 extern "C" JNIEXPORT jlong JNICALL
 Java_com_google_android_filament_Material_nBuilderBuild(JNIEnv *env, jclass,
-        jlong nativeEngine, jobject buffer_, jint size, jint shBandCount) {
+        jlong nativeEngine, jobject buffer_, jint size) {
     Engine* engine = (Engine*) nativeEngine;
     AutoBuffer buffer(env, buffer_, size);
-    auto builder = Material::Builder();
-    if (shBandCount) {
-        builder.sphericalHarmonicsBandCount(shBandCount);
-    }
-    Material* material = builder
+    Material* material = Material::Builder()
             .package(buffer.getData(), buffer.getSize())
             .build(*engine);
-
     return (jlong) material;
 }
 

android/filament-android/src/main/cpp/RenderableManager.cpp

@@ -104,14 +104,6 @@ Java_com_google_android_filament_RenderableManager_nBuilderGeometry__JIIJJIIII(J
             (size_t) count);
 }
 
-extern "C"
-JNIEXPORT void JNICALL
-Java_com_google_android_filament_RenderableManager_nBuilderGeometryType(JNIEnv*, jclass,
-        jlong nativeBuilder, int type) {
-    RenderableManager::Builder *builder = (RenderableManager::Builder *) nativeBuilder;
-    builder->geometryType((RenderableManager::Builder::GeometryType)type);
-}
-
 extern "C"
 JNIEXPORT void JNICALL
 Java_com_google_android_filament_RenderableManager_nBuilderMaterial(JNIEnv*, jclass,
@@ -245,18 +237,12 @@ Java_com_google_android_filament_RenderableManager_nBuilderMorphing(JNIEnv*, jcl
 }
 
 extern "C" JNIEXPORT void JNICALL
-Java_com_google_android_filament_RenderableManager_nBuilderMorphingStandard(JNIEnv*, jclass,
-        jlong nativeBuilder, jlong nativeMorphTargetBuffer) {
+Java_com_google_android_filament_RenderableManager_nBuilderSetMorphTargetBufferAt(JNIEnv*, jclass,
+        jlong nativeBuilder, int level, int primitiveIndex, jlong nativeMorphTargetBuffer,
+        int offset, int count) {
     RenderableManager::Builder *builder = (RenderableManager::Builder *) nativeBuilder;
     MorphTargetBuffer *morphTargetBuffer = (MorphTargetBuffer *) nativeMorphTargetBuffer;
-    builder->morphing(morphTargetBuffer);
-}
-
-extern "C" JNIEXPORT void JNICALL
-Java_com_google_android_filament_RenderableManager_nBuilderSetMorphTargetBufferOffsetAt(JNIEnv*, jclass,
-        jlong nativeBuilder, int level, int primitiveIndex, int offset) {
-    RenderableManager::Builder *builder = (RenderableManager::Builder *) nativeBuilder;
-    builder->morphing(level, primitiveIndex, offset);
+    builder->morphing(level, primitiveIndex, morphTargetBuffer, offset, count);
 }
 
 extern "C" JNIEXPORT void JNICALL
@@ -328,12 +314,13 @@ Java_com_google_android_filament_RenderableManager_nSetMorphWeights(JNIEnv* env,
 }
 
 extern "C" JNIEXPORT void JNICALL
-Java_com_google_android_filament_RenderableManager_nSetMorphTargetBufferOffsetAt(JNIEnv*,
+Java_com_google_android_filament_RenderableManager_nSetMorphTargetBufferAt(JNIEnv*,
         jclass, jlong nativeRenderableManager, jint i, int level, jint primitiveIndex,
-        jlong, jint offset) {
+        jlong nativeMorphTargetBuffer, jint offset, jint count) {
     RenderableManager *rm = (RenderableManager *) nativeRenderableManager;
-    rm->setMorphTargetBufferOffsetAt((RenderableManager::Instance) i, (uint8_t) level,
-            (size_t) primitiveIndex, (size_t) offset);
+    MorphTargetBuffer *morphTargetBuffer = (MorphTargetBuffer *) nativeMorphTargetBuffer;
+    rm->setMorphTargetBufferAt((RenderableManager::Instance) i, (uint8_t) level,
+            (size_t) primitiveIndex, morphTargetBuffer, (size_t) offset, (size_t) count);
 }
 
 extern "C" JNIEXPORT jint JNICALL

android/filament-android/src/main/cpp/Renderer.cpp

@@ -28,14 +28,6 @@
 using namespace filament;
 using namespace backend;
 
-
-extern "C" JNIEXPORT void JNICALL
-Java_com_google_android_filament_Renderer_nSkipFrame(JNIEnv *, jclass, jlong nativeRenderer,
-        jlong vsyncSteadyClockTimeNano) {
-    Renderer *renderer = (Renderer *) nativeRenderer;
-    renderer->skipFrame(uint64_t(vsyncSteadyClockTimeNano));
-}
-
 extern "C" JNIEXPORT jboolean JNICALL
 Java_com_google_android_filament_Renderer_nBeginFrame(JNIEnv *, jclass, jlong nativeRenderer,
         jlong nativeSwapChain, jlong frameTimeNanos) {
@@ -195,10 +187,3 @@ Java_com_google_android_filament_Renderer_nSetPresentationTime(JNIEnv *, jclass
     Renderer *renderer = (Renderer *) nativeRenderer;
     renderer->setPresentationTime(monotonicClockNanos);
 }
-
-extern "C" JNIEXPORT void JNICALL
-Java_com_google_android_filament_Renderer_nSetVsyncTime(JNIEnv *, jclass,
-    jlong nativeRenderer, jlong steadyClockTimeNano) {
-    Renderer *renderer = (Renderer *) nativeRenderer;
-    renderer->setVsyncTime(steadyClockTimeNano);
-}

android/filament-android/src/main/cpp/View.cpp

@@ -49,12 +49,6 @@ Java_com_google_android_filament_View_nSetCamera(JNIEnv*, jclass,
     view->setCamera(camera);
 }
 
-extern "C" JNIEXPORT jboolean JNICALL
-Java_com_google_android_filament_View_nHasCamera(JNIEnv*, jclass, jlong nativeView) {
-    View* view = (View*) nativeView;
-    return (jboolean)view->hasCamera();
-}
-
 extern "C" JNIEXPORT void JNICALL
 Java_com_google_android_filament_View_nSetColorGrading(JNIEnv*, jclass,
         jlong nativeView, jlong nativeColorGrading) {
@@ -222,20 +216,6 @@ Java_com_google_android_filament_View_nIsFrontFaceWindingInverted(JNIEnv*,
     return static_cast<jboolean>(view->isFrontFaceWindingInverted());
 }
 
-extern "C" JNIEXPORT void JNICALL
-Java_com_google_android_filament_View_nSetTransparentPickingEnabled(JNIEnv*,
-        jclass, jlong nativeView, jboolean enabled) {
-    View* view = (View*) nativeView;
-    view->setTransparentPickingEnabled(enabled);
-}
-
-extern "C" JNIEXPORT jboolean JNICALL
-Java_com_google_android_filament_View_nIsTransparentPickingEnabled(JNIEnv*,
-        jclass, jlong nativeView) {
-    View* view = (View*) nativeView;
-    return static_cast<jboolean>(view->isTransparentPickingEnabled());
-}
-
 extern "C" JNIEXPORT void JNICALL
 Java_com_google_android_filament_View_nSetAmbientOcclusion(JNIEnv*, jclass, jlong nativeView, jint ordinal) {
     View* view = (View*) nativeView;
@@ -545,12 +525,3 @@ Java_com_google_android_filament_View_nGetFogEntity(JNIEnv *env, jclass clazz,
     View *view = (View *) nativeView;
     return (jint)view->getFogEntity().getId();
 }
-
-extern "C"
-JNIEXPORT void JNICALL
-Java_com_google_android_filament_View_nClearFrameHistory(JNIEnv *env, jclass clazz,
-        jlong nativeView, jlong nativeEngine) {
-    View *view = (View *) nativeView;
-    Engine *engine = (Engine *) nativeEngine;
-    view->clearFrameHistory(*engine);
-}

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

@@ -159,12 +159,9 @@ public class Engine {
     };
 
     /**
-     * The type of technique for stereoscopic rendering. (Note that the materials used will need to be
-     * compatible with the chosen technique.)
+     * The type of technique for stereoscopic rendering
      */
     public enum StereoscopicType {
-        /** No stereoscopic rendering. */
-        NONE,
         /** Stereoscopic rendering is performed using instanced rendering technique. */
         INSTANCED,
         /** Stereoscopic rendering is performed using the multiview feature from the graphics backend. */
@@ -224,12 +221,11 @@ public class Engine {
             nSetBuilderConfig(mNativeBuilder, config.commandBufferSizeMB,
                     config.perRenderPassArenaSizeMB, config.driverHandleArenaSizeMB,
                     config.minCommandBufferSizeMB, config.perFrameCommandsSizeMB,
-                    config.jobSystemThreadCount, config.disableParallelShaderCompile,
+                    config.jobSystemThreadCount,
+                    config.textureUseAfterFreePoolSize, config.disableParallelShaderCompile,
                     config.stereoscopicType.ordinal(), config.stereoscopicEyeCount,
                     config.resourceAllocatorCacheSizeMB, config.resourceAllocatorCacheMaxAge,
-                    config.disableHandleUseAfterFreeCheck,
-                    config.preferredShaderLanguage.ordinal(),
-                    config.forceGLES2Context, config.assertNativeWindowIsValid);
+                    config.disableHandleUseAfterFreeCheck);
             return this;
         }
 
@@ -247,28 +243,15 @@ public class Engine {
         /**
          * Sets the initial paused state of the rendering thread.
          *
-         * <p>Warning: This is an experimental API. See {@link Engine#setPaused(boolean)} for
-         * caveats.
-         *
          * @param paused Whether to start the rendering thread paused.
          * @return A reference to this Builder for chaining calls.
+         * @warning Experimental.
          */
         public Builder paused(boolean paused) {
             nSetBuilderPaused(mNativeBuilder, paused);
             return this;
         }
 
-        /**
-         * Set a feature flag value. This is the only way to set constant feature flags.
-         * @param name feature name
-         * @param value true to enable, false to disable
-         * @return A reference to this Builder for chaining calls.
-         */
-        public Builder feature(@NonNull String name, boolean value) {
-            nSetBuilderFeature(mNativeBuilder, name, value);
-            return this;
-        }
-
         /**
          * Creates an instance of Engine
          *
@@ -404,7 +387,6 @@ public class Engine {
         /**
          * Set to `true` to forcibly disable parallel shader compilation in the backend.
          * Currently only honored by the GL backend.
-         * @Deprecated use "backend.disable_parallel_shader_compile" feature flag instead
          */
         public boolean disableParallelShaderCompile = false;
 
@@ -419,7 +401,7 @@ public class Engine {
          *
          * @see View#setStereoscopicOptions
          */
-        public StereoscopicType stereoscopicType = StereoscopicType.NONE;
+        public StereoscopicType stereoscopicType = StereoscopicType.INSTANCED;
 
         /**
          * The number of eyes to render when stereoscopic rendering is enabled. Supported values are
@@ -430,61 +412,20 @@ public class Engine {
          */
         public long stereoscopicEyeCount = 2;
 
-        /**
+        /*
          * @Deprecated This value is no longer used.
          */
         public long resourceAllocatorCacheSizeMB = 64;
 
-        /**
-         * This value determines how many frames texture entries are kept for in the cache. This
-         * is a soft limit, meaning some texture older than this are allowed to stay in the cache.
-         * Typically only one texture is evicted per frame.
-         * The default is 1.
+        /*
+         * This value determines for how many frames are texture entries kept in the cache.
          */
-        public long resourceAllocatorCacheMaxAge = 1;
+        public long resourceAllocatorCacheMaxAge = 2;
 
-        /**
+        /*
          * Disable backend handles use-after-free checks.
-         * @Deprecated use "backend.disable_handle_use_after_free_check" feature flag instead
          */
         public boolean disableHandleUseAfterFreeCheck = false;
-
-        /**
-         * Sets a preferred shader language for Filament to use.
-         *
-         * The Metal backend supports two shader languages: MSL (Metal Shading Language) and
-         * METAL_LIBRARY (precompiled .metallib). This option controls which shader language is
-         * used when materials contain both.
-         *
-         * By default, when preferredShaderLanguage is unset, Filament will prefer METAL_LIBRARY
-         * shaders if present within a material, falling back to MSL. Setting
-         * preferredShaderLanguage to ShaderLanguage::MSL will instead instruct Filament to check
-         * for the presence of MSL in a material first, falling back to METAL_LIBRARY if MSL is not
-         * present.
-         *
-         * When using a non-Metal backend, setting this has no effect.
-         */
-        public enum ShaderLanguage {
-            DEFAULT,
-            MSL,
-            METAL_LIBRARY,
-        };
-        public ShaderLanguage preferredShaderLanguage = ShaderLanguage.DEFAULT;
-
-        /**
-         * When the OpenGL ES backend is used, setting this value to true will force a GLES2.0
-         * context if supported by the Platform, or if not, will have the backend pretend
-         * it's a GLES2 context. Ignored on other backends.
-         */
-        public boolean forceGLES2Context = false;
-
-        /**
-         * Assert the native window associated to a SwapChain is valid when calling makeCurrent().
-         * This is only supported for:
-         *      - PlatformEGLAndroid
-         * @Deprecated use "backend.opengl.assert_native_window_is_valid" feature flag instead
-         */
-        public boolean assertNativeWindowIsValid = false;
     }
 
     private Engine(long nativeEngine, Config config) {
@@ -707,11 +648,11 @@ public class Engine {
 
     /**
      * Returns the maximum number of stereoscopic eyes supported by Filament. The actual number of
-     * eyes rendered is set at Engine creation time with the {@link Config#stereoscopicEyeCount}
-     * setting.
+     * eyes rendered is set at Engine creation time with the {@link
+     * Engine#Config#stereoscopicEyeCount} setting.
      *
      * @return the max number of stereoscopic eyes supported
-     * @see Config#stereoscopicEyeCount
+     * @see Engine#Config#stereoscopicEyeCount
      */
     public long getMaxStereoscopicEyes() {
         return nGetMaxStereoscopicEyes(getNativeObject());
@@ -906,25 +847,6 @@ public class Engine {
         return nIsValidMaterial(getNativeObject(), object.getNativeObject());
     }
 
-    /**
-     * Returns whether the object is valid.
-     * @param ma Material
-     * @param mi MaterialInstance to check for validity
-     * @return returns true if the specified object is valid.
-     */
-    public boolean isValidMaterialInstance(@NonNull Material ma, MaterialInstance mi) {
-        return nIsValidMaterialInstance(getNativeObject(), ma.getNativeObject(), mi.getNativeObject());
-    }
-
-    /**
-     * Returns whether the object is valid.
-     * @param object Object to check for validity
-     * @return returns true if the specified object is valid.
-     */
-    public boolean isValidExpensiveMaterialInstance(@NonNull MaterialInstance object) {
-        return nIsValidExpensiveMaterialInstance(getNativeObject(), object.getNativeObject());
-    }
-
     /**
      * Returns whether the object is valid.
      * @param object Object to check for validity
@@ -1285,85 +1207,14 @@ public class Engine {
         nFlush(getNativeObject());
     }
 
-    /**
-     * Get paused state of rendering thread.
-     *
-     * <p>Warning: This is an experimental API.
-     *
-     * @see #setPaused
-     */
-    public boolean isPaused() {
-        return nIsPaused(getNativeObject());
-    }
-
     /**
      * Pause or resume the rendering thread.
-     *
-     * <p>Warning: This is an experimental API. In particular, note the following caveats.
-     *
-     * <ul><li>
-     * Buffer callbacks will never be called as long as the rendering thread is paused.
-     * Do not rely on a buffer callback to unpause the thread.
-     * </li><li>
-     * While the rendering thread is paused, rendering commands will continue to be queued until the
-     * buffer limit is reached. When the limit is reached, the program will abort.
-     * </li></ul>
+     * @warning Experimental.
      */
     public void setPaused(boolean paused) {
         nSetPaused(getNativeObject(), paused);
     }
 
-    /**
-     * Switch the command queue to unprotected mode. Protected mode can be activated via
-     * Renderer::beginFrame() using a protected SwapChain.
-     * @see Renderer
-     * @see SwapChain
-     */
-    public void unprotected() {
-        nUnprotected(getNativeObject());
-    }
-
-    /**
-     * Get the current time. This is a convenience function that simply returns the
-     * time in nanosecond since epoch of std::chrono::steady_clock.
-     * @return current time in nanosecond since epoch of std::chrono::steady_clock.
-     * @see Renderer#beginFrame
-     */
-    public static native long getSteadyClockTimeNano();
-
-
-    /**
-     * Checks if a feature flag exists
-     * @param name name of the feature flag to check
-     * @return true if it exists false otherwise
-     */
-    public boolean hasFeatureFlag(@NonNull String name) {
-        return nHasFeatureFlag(mNativeObject, name);
-    }
-
-    /**
-     * Set the value of a non-constant feature flag.
-     * @param name name of the feature flag to set
-     * @param value value to set
-     * @return true if the value was set, false if the feature flag is constant or doesn't exist.
-     */
-    public boolean setFeatureFlag(@NonNull String name, boolean value) {
-        return nSetFeatureFlag(mNativeObject, name, value);
-    }
-
-    /**
-     * Retrieves the value of any feature flag.
-     * @param name name of the feature flag
-     * @return the value of the flag if it exists
-     * @exception IllegalArgumentException is thrown if the feature flag doesn't exist
-     */
-    public boolean getFeatureFlag(@NonNull String name) {
-        if (!hasFeatureFlag(name)) {
-            throw new IllegalArgumentException("The feature flag \"" + name + "\" doesn't exist");
-        }
-        return nGetFeatureFlag(mNativeObject, name);
-    }
-
     @UsedByReflection("TextureHelper.java")
     public long getNativeObject() {
         if (mNativeObject == 0) {
@@ -1429,8 +1280,6 @@ public class Engine {
     private static native boolean nIsValidSkinningBuffer(long nativeEngine, long nativeSkinningBuffer);
     private static native boolean nIsValidIndirectLight(long nativeEngine, long nativeIndirectLight);
     private static native boolean nIsValidMaterial(long nativeEngine, long nativeMaterial);
-    private static native boolean nIsValidMaterialInstance(long nativeEngine, long nativeMaterial, long nativeMaterialInstance);
-    private static native boolean nIsValidExpensiveMaterialInstance(long nativeEngine, long nativeMaterialInstance);
     private static native boolean nIsValidSkybox(long nativeEngine, long nativeSkybox);
     private static native boolean nIsValidColorGrading(long nativeEngine, long nativeColorGrading);
     private static native boolean nIsValidTexture(long nativeEngine, long nativeTexture);
@@ -1439,9 +1288,7 @@ public class Engine {
     private static native void nDestroyEntity(long nativeEngine, int entity);
     private static native void nFlushAndWait(long nativeEngine);
     private static native void nFlush(long nativeEngine);
-    private static native boolean nIsPaused(long nativeEngine);
     private static native void nSetPaused(long nativeEngine, boolean paused);
-    private static native void nUnprotected(long nativeEngine);
     private static native long nGetTransformManager(long nativeEngine);
     private static native long nGetLightManager(long nativeEngine);
     private static native long nGetRenderableManager(long nativeEngine);
@@ -1453,9 +1300,6 @@ public class Engine {
     private static native int nGetSupportedFeatureLevel(long nativeEngine);
     private static native int nSetActiveFeatureLevel(long nativeEngine, int ordinal);
     private static native int nGetActiveFeatureLevel(long nativeEngine);
-    private static native boolean nHasFeatureFlag(long nativeEngine, String name);
-    private static native boolean nSetFeatureFlag(long nativeEngine, String name, boolean value);
-    private static native boolean nGetFeatureFlag(long nativeEngine, String name);
 
     private static native long nCreateBuilder();
     private static native void nDestroyBuilder(long nativeBuilder);
@@ -1463,14 +1307,12 @@ public class Engine {
     private static native void nSetBuilderConfig(long nativeBuilder, long commandBufferSizeMB,
             long perRenderPassArenaSizeMB, long driverHandleArenaSizeMB,
             long minCommandBufferSizeMB, long perFrameCommandsSizeMB, long jobSystemThreadCount,
-            boolean disableParallelShaderCompile, int stereoscopicType, long stereoscopicEyeCount,
+            long textureUseAfterFreePoolSize, boolean disableParallelShaderCompile,
+            int stereoscopicType, long stereoscopicEyeCount,
             long resourceAllocatorCacheSizeMB, long resourceAllocatorCacheMaxAge,
-            boolean disableHandleUseAfterFreeCheck,
-            int preferredShaderLanguage,
-            boolean forceGLES2Context, boolean assertNativeWindowIsValid);
+            boolean disableHandleUseAfterFreeCheck);
     private static native void nSetBuilderFeatureLevel(long nativeBuilder, int ordinal);
     private static native void nSetBuilderSharedContext(long nativeBuilder, long sharedContext);
     private static native void nSetBuilderPaused(long nativeBuilder, boolean paused);
-    private static native void nSetBuilderFeature(long nativeBuilder, String name, boolean value);
     private static native long nBuilderBuild(long nativeBuilder);
 }

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

@@ -346,7 +346,6 @@ public class Material {
     public static class Builder {
         private Buffer mBuffer;
         private int mSize;
-        private int mShBandCount = 0;
 
         /**
          * Specifies the material data. The material data is a binary blob produced by
@@ -362,22 +361,6 @@ public class Material {
             return this;
         }
 
-        /**
-         * Sets the quality of the indirect lights computations. This is only taken into account
-         * if this material is lit and in the surface domain. This setting will affect the
-         * IndirectLight computation if one is specified on the Scene and Spherical Harmonics
-         * are used for the irradiance.
-         *
-         * @param shBandCount Number of spherical harmonic bands. Must be 1, 2 or 3 (default).
-         * @return Reference to this Builder for chaining calls.
-         * @see IndirectLight
-         */
-        @NonNull
-        public Builder sphericalHarmonicsBandCount(@IntRange(from = 0) int shBandCount) {
-            mShBandCount = shBandCount;
-            return this;
-        }
-
         /**
          * Creates and returns the Material object.
          *
@@ -389,8 +372,7 @@ public class Material {
          */
         @NonNull
         public Material build(@NonNull Engine engine) {
-            long nativeMaterial = nBuilderBuild(engine.getNativeObject(),
-                mBuffer, mSize, mShBandCount);
+            long nativeMaterial = nBuilderBuild(engine.getNativeObject(), mBuffer, mSize);
             if (nativeMaterial == 0) throw new IllegalStateException("Couldn't create Material");
             return new Material(nativeMaterial);
         }
@@ -1041,7 +1023,7 @@ public class Material {
         mNativeObject = 0;
     }
 
-    private static native long nBuilderBuild(long nativeEngine, @NonNull Buffer buffer, int size, int shBandCount);
+    private static native long nBuilderBuild(long nativeEngine, @NonNull Buffer buffer, int size);
     private static native long nCreateInstance(long nativeMaterial);
     private static native long nCreateInstanceWithName(long nativeMaterial, @NonNull String name);
     private static native long nGetDefaultInstance(long nativeMaterial);

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

@@ -74,7 +74,7 @@ public class MorphTargetBuffer {
          *
          * @exception IllegalStateException if the MorphTargetBuffer could not be created
          *
-         * @see #setMorphTargetBufferOffsetAt
+         * @see #setMorphTargetBufferAt
          */
         @NonNull
         public MorphTargetBuffer build(@NonNull Engine engine) {

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

@@ -175,32 +175,6 @@ public class RenderableManager {
             return this;
         }
 
-        /**
-         * Type of geometry for a Renderable
-         */
-        public enum GeometryType {
-            /** dynamic gemoetry has no restriction */
-            DYNAMIC,
-            /** bounds and world space transform are immutable */
-            STATIC_BOUNDS,
-            /** skinning/morphing not allowed and Vertex/IndexBuffer immutables */
-            STATIC
-        }
-
-        /**
-         * Specify whether this renderable has static bounds. In this context his means that
-         * the renderable's bounding box cannot change and that the renderable's transform is
-         * assumed immutable. Changing the renderable's transform via the TransformManager
-         * can lead to corrupted graphics. Note that skinning and morphing are not forbidden.
-         * Disabled by default.
-         * @param enable whether this renderable has static bounds. false by default.
-         */
-        @NonNull
-        public Builder geometryType(GeometryType type) {
-            nBuilderGeometryType(mNativeBuilder, type.ordinal());
-            return this;
-        }
-
         /**
          * Binds a material instance to the specified primitive.
          *
@@ -524,7 +498,14 @@ public class RenderableManager {
         }
 
         /**
-         * Controls if the renderable has legacy vertex morphing targets, zero by default.
+         * Controls if the renderable has vertex morphing targets, zero by default. This is
+         * required to enable GPU morphing.
+         *
+         * <p>Filament supports two morphing modes: standard (default) and legacy.</p>
+         *
+         * <p>For standard morphing, A {@link MorphTargetBuffer} must be created and provided via
+         * {@link RenderableManager#setMorphTargetBufferAt}. Standard morphing supports up to
+         * <code>CONFIG_MAX_MORPH_TARGET_COUNT</code> morph targets.</p>
          *
          * For legacy morphing, the attached {@link VertexBuffer} must provide data in the
          * appropriate {@link VertexBuffer.VertexAttribute} slots (<code>MORPH_POSITION_0</code> etc).
@@ -542,22 +523,6 @@ public class RenderableManager {
             return this;
         }
 
-        /**
-         * Controls if the renderable has vertex morphing targets, zero by default.
-         *
-         * <p>For standard morphing, A {@link MorphTargetBuffer} must be provided.
-         * Standard morphing supports up to
-         * <code>CONFIG_MAX_MORPH_TARGET_COUNT</code> morph targets.</p>
-         *
-         * <p>See also {@link RenderableManager#setMorphWeights}, which can be called on a per-frame basis
-         * to advance the animation.</p>
-         */
-        @NonNull
-        public Builder morphing(@NonNull MorphTargetBuffer morphTargetBuffer) {
-            nBuilderMorphingStandard(mNativeBuilder, morphTargetBuffer.getNativeObject());
-            return this;
-        }
-
         /**
          * Specifies the morph target buffer for a primitive.
          *
@@ -569,13 +534,31 @@ public class RenderableManager {
          *
          * @param level the level of detail (lod), only 0 can be specified
          * @param primitiveIndex zero-based index of the primitive, must be less than the count passed to Builder constructor
+         * @param morphTargetBuffer specifies the morph target buffer
          * @param offset specifies where in the morph target buffer to start reading (expressed as a number of vertices)
+         * @param count number of vertices in the morph target buffer to read, must equal the geometry's count (for triangles, this should be a multiple of 3)
          */
         @NonNull
         public Builder morphing(@IntRange(from = 0) int level,
                                 @IntRange(from = 0) int primitiveIndex,
-                                @IntRange(from = 0) int offset) {
-            nBuilderSetMorphTargetBufferOffsetAt(mNativeBuilder, level, primitiveIndex, offset);
+                                @NonNull MorphTargetBuffer morphTargetBuffer,
+                                @IntRange(from = 0) int offset,
+                                @IntRange(from = 0) int count) {
+            nBuilderSetMorphTargetBufferAt(mNativeBuilder, level, primitiveIndex,
+                    morphTargetBuffer.getNativeObject(), offset, count);
+            return this;
+        }
+
+        /**
+         * Utility method to specify morph target buffer for a primitive.
+         * For details, see the {@link RenderableManager.Builder#morphing}.
+         */
+        @NonNull
+        public Builder morphing(@IntRange(from = 0) int level,
+                                @IntRange(from = 0) int primitiveIndex,
+                                @NonNull MorphTargetBuffer morphTargetBuffer) {
+            nBuilderSetMorphTargetBufferAt(mNativeBuilder, level, primitiveIndex,
+                    morphTargetBuffer.getNativeObject(), 0, morphTargetBuffer.getVertexCount());
             return this;
         }
 
@@ -678,11 +661,26 @@ public class RenderableManager {
      *
      * @see Builder#morphing
      */
-    public void setMorphTargetBufferOffsetAt(@EntityInstance int i,
+    public void setMorphTargetBufferAt(@EntityInstance int i,
                                        @IntRange(from = 0) int level,
                                        @IntRange(from = 0) int primitiveIndex,
-                                       @IntRange(from = 0) int offset) {
-        nSetMorphTargetBufferOffsetAt(mNativeObject, i, level, primitiveIndex, 0, offset);
+                                       @NonNull MorphTargetBuffer morphTargetBuffer,
+                                       @IntRange(from = 0) int offset,
+                                       @IntRange(from = 0) int count) {
+        nSetMorphTargetBufferAt(mNativeObject, i, level, primitiveIndex,
+                morphTargetBuffer.getNativeObject(), offset, count);
+    }
+
+    /**
+     * Utility method to change morph target buffer for the given primitive.
+     * For details, see the {@link RenderableManager#setMorphTargetBufferAt}.
+     */
+    public void setMorphTargetBufferAt(@EntityInstance int i,
+                                       @IntRange(from = 0) int level,
+                                       @IntRange(from = 0) int primitiveIndex,
+                                       @NonNull MorphTargetBuffer morphTargetBuffer) {
+        nSetMorphTargetBufferAt(mNativeObject, i, level, primitiveIndex,
+                morphTargetBuffer.getNativeObject(), 0, morphTargetBuffer.getVertexCount());
     }
 
     /**
@@ -966,7 +964,6 @@ public class RenderableManager {
     private static native void nBuilderGeometry(long nativeBuilder, int index, int value, long nativeVertexBuffer, long nativeIndexBuffer);
     private static native void nBuilderGeometry(long nativeBuilder, int index, int value, long nativeVertexBuffer, long nativeIndexBuffer, int offset, int count);
     private static native void nBuilderGeometry(long nativeBuilder, int index, int value, long nativeVertexBuffer, long nativeIndexBuffer, int offset, int minIndex, int maxIndex, int count);
-    private static native void nBuilderGeometryType(long nativeBuilder, int type);
     private static native void nBuilderMaterial(long nativeBuilder, int index, long nativeMaterialInstance);
     private static native void nBuilderBlendOrder(long nativeBuilder, int index, int blendOrder);
     private static native void nBuilderGlobalBlendOrderEnabled(long nativeBuilder, int index, boolean enabled);
@@ -982,8 +979,7 @@ public class RenderableManager {
     private static native int nBuilderSkinningBones(long nativeBuilder, int boneCount, Buffer bones, int remaining);
     private static native void nBuilderSkinningBuffer(long nativeBuilder, long nativeSkinningBuffer, int boneCount, int offset);
     private static native void nBuilderMorphing(long nativeBuilder, int targetCount);
-    private static native void nBuilderMorphingStandard(long nativeBuilder, long nativeMorphTargetBuffer);
-    private static native void nBuilderSetMorphTargetBufferOffsetAt(long nativeBuilder, int level, int primitiveIndex, int offset);
+    private static native void nBuilderSetMorphTargetBufferAt(long nativeBuilder, int level, int primitiveIndex, long nativeMorphTargetBuffer, int offset, int count);
     private static native void nBuilderEnableSkinningBuffers(long nativeBuilder, boolean enabled);
     private static native void nBuilderFog(long nativeBuilder, boolean enabled);
     private static native void nBuilderLightChannel(long nativeRenderableManager, int channel, boolean enable);
@@ -993,7 +989,7 @@ public class RenderableManager {
     private static native int nSetBonesAsMatrices(long nativeObject, int i, Buffer matrices, int remaining, int boneCount, int offset);
     private static native int nSetBonesAsQuaternions(long nativeObject, int i, Buffer quaternions, int remaining, int boneCount, int offset);
     private static native void nSetMorphWeights(long nativeObject, int instance, float[] weights, int offset);
-    private static native void nSetMorphTargetBufferOffsetAt(long nativeObject, int i, int level, int primitiveIndex, long nativeMorphTargetBuffer, int offset);
+    private static native void nSetMorphTargetBufferAt(long nativeObject, int i, int level, int primitiveIndex, long nativeMorphTargetBuffer, int offset, int count);
     private static native int nGetMorphTargetCount(long nativeObject, int i);
     private static native void nSetAxisAlignedBoundingBox(long nativeRenderableManager, int i, float cx, float cy, float cz, float ex, float ey, float ez);
     private static native void nSetLayerMask(long nativeRenderableManager, int i, int select, int value);

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

@@ -284,33 +284,6 @@ public class Renderer {
         nSetPresentationTime(getNativeObject(), monotonicClockNanos);
     }
 
-    /**
-     * The use of this method is optional. It sets the VSYNC time expressed as the duration in
-     * nanosecond since epoch of std::chrono::steady_clock.
-     * If called, passing 0 to frameTimeNanos in Renderer.BeginFrame will use this
-     * time instead.
-     * @param steadyClockTimeNano duration in nanosecond since epoch of std::chrono::steady_clock
-     * @see Engine#getSteadyClockTimeNano
-     * @see Renderer#beginFrame
-     */
-    public void setVsyncTime(long steadyClockTimeNano) {
-        nSetVsyncTime(getNativeObject(), steadyClockTimeNano);
-    }
-
-    /**
-     * Call skipFrame when momentarily skipping frames, for instance if the content of the
-     * scene doesn't change.
-     *
-     * @param vsyncSteadyClockTimeNano The time in nanoseconds when the frame started being rendered,
-     *                       in the {@link System#nanoTime()} timebase. Divide this value by 1000000 to
-     *                       convert it to the {@link android.os.SystemClock#uptimeMillis()}
-     *                       time base. This typically comes from
-     *                       {@link android.view.Choreographer.FrameCallback}.
-     */
-    public void skipFrame(long vsyncSteadyClockTimeNano) {
-        nSkipFrame(getNativeObject(), vsyncSteadyClockTimeNano);
-    }
-
     /**
      * Sets up a frame for this <code>Renderer</code>.
      * <p><code>beginFrame</code> manages frame pacing, and returns whether or not a frame should be
@@ -729,8 +702,6 @@ public class Renderer {
     }
 
     private static native void nSetPresentationTime(long nativeObject, long monotonicClockNanos);
-    private static native void nSetVsyncTime(long nativeObject, long steadyClockTimeNano);
-    private static native void nSkipFrame(long nativeObject, long vsyncSteadyClockTimeNano);
     private static native boolean nBeginFrame(long nativeRenderer, long nativeSwapChain, long frameTimeNanos);
     private static native void nEndFrame(long nativeRenderer);
     private static native void nRender(long nativeRenderer, long nativeView);

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

@@ -241,15 +241,6 @@ public class View {
         nSetCamera(getNativeObject(), camera == null ? 0 : camera.getNativeObject());
     }
 
-    /**
-     * Query whether a camera is set.
-     * @return true if a camera is set, false otherwise
-     * @see #setCamera
-     */
-    public boolean hasCamera() {
-        return nHasCamera(getNativeObject());
-    }
-
     /**
      * Gets this View's associated Camera, or null if none has been assigned.
      *
@@ -745,33 +736,6 @@ public class View {
         nSetFrontFaceWindingInverted(getNativeObject(), inverted);
     }
 
-    /**
-     * Returns true if transparent picking is enabled.
-     *
-     * @see #setTransparentPickingEnabled
-     */
-    public boolean isTransparentPickingEnabled() {
-        return nIsTransparentPickingEnabled(getNativeObject());
-    }
-
-    /**
-     * Enables or disables transparent picking. Disabled by default.
-     *
-     * When transparent picking is enabled, View::pick() will pick from both
-     * transparent and opaque renderables. When disabled, View::pick() will only
-     * pick from opaque renderables.
-     *
-     * <p>
-     * Transparent picking will create an extra pass for rendering depth
-     * from both transparent and opaque renderables. 
-     * </p>
-     *
-     * @param enabled true enables transparent picking, false disables it.
-     */
-    public void setTransparentPickingEnabled(boolean enabled) {
-        nSetTransparentPickingEnabled(getNativeObject(), enabled);
-    }
-
     /**
      * Sets options relative to dynamic lighting for this view.
      *
@@ -1260,18 +1224,6 @@ public class View {
         return nGetFogEntity(getNativeObject());
     }
 
-    /**
-     * When certain temporal features are used (e.g.: TAA or Screen-space reflections), the view
-     * keeps a history of previous frame renders associated with the Renderer the view was last
-     * used with. When switching Renderer, it may be necessary to clear that history by calling
-     * this method. Similarly, if the whole content of the screen change, like when a cut-scene
-     * starts, clearing the history might be needed to avoid artifacts due to the previous frame
-     * being very different.
-     */
-    public void clearFrameHistory(Engine engine) {
-        nClearFrameHistory(getNativeObject(), engine.getNativeObject());
-    }
-
     public long getNativeObject() {
         if (mNativeObject == 0) {
             throw new IllegalStateException("Calling method on destroyed View");
@@ -1286,7 +1238,6 @@ public class View {
     private static native void nSetName(long nativeView, String name);
     private static native void nSetScene(long nativeView, long nativeScene);
     private static native void nSetCamera(long nativeView, long nativeCamera);
-    private static native boolean nHasCamera(long nativeView);
     private static native void nSetViewport(long nativeView, int left, int bottom, int width, int height);
     private static native void nSetVisibleLayers(long nativeView, int select, int value);
     private static native void nSetShadowingEnabled(long nativeView, boolean enabled);
@@ -1308,8 +1259,6 @@ public class View {
     private static native boolean nIsPostProcessingEnabled(long nativeView);
     private static native void nSetFrontFaceWindingInverted(long nativeView, boolean inverted);
     private static native boolean nIsFrontFaceWindingInverted(long nativeView);
-    private static native void nSetTransparentPickingEnabled(long nativeView, boolean enabled);
-    private static native boolean nIsTransparentPickingEnabled(long nativeView);
     private static native void nSetAmbientOcclusion(long nativeView, int ordinal);
     private static native int nGetAmbientOcclusion(long nativeView);
     private static native void nSetAmbientOcclusionOptions(long nativeView, float radius, float bias, float power, float resolution, float intensity, float bilateralThreshold, int quality, int lowPassFilter, int upsampling, boolean enabled, boolean bentNormals, float minHorizonAngleRad);
@@ -1335,7 +1284,7 @@ public class View {
     private static native void nSetMaterialGlobal(long nativeView, int index, float x, float y, float z, float w);
     private static native void nGetMaterialGlobal(long nativeView, int index, float[] out);
     private static native int nGetFogEntity(long nativeView);
-    private static native void nClearFrameHistory(long nativeView, long nativeEngine);
+
 
     /**
      * List of available ambient occlusion techniques.

android/filament-utils-android/CMakeLists.txt

@@ -31,7 +31,6 @@ set_target_properties(iblprefilter PROPERTIES IMPORTED_LOCATION
         ${FILAMENT_DIR}/lib/${ANDROID_ABI}/libfilament-iblprefilter.a)
 
 set(CMAKE_SHARED_LINKER_FLAGS_RELEASE "${CMAKE_SHARED_LINKER_FLAGS_RELEASE} -Wl,--version-script=${CMAKE_CURRENT_SOURCE_DIR}/libfilament-utils-jni.map")
-set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} -Wl,-z,max-page-size=16384")
 
 add_library(filament-utils-jni SHARED
         src/main/cpp/AutomationEngine.cpp

android/filament-utils-android/src/main/cpp/Manipulator.cpp

@@ -125,11 +125,6 @@ extern "C" JNIEXPORT void Java_com_google_android_filament_utils_Manipulator_nBu
     builder->groundPlane(a, b, c, d);
 }
 
-extern "C" JNIEXPORT void Java_com_google_android_filament_utils_Manipulator_nBuilderPanning(JNIEnv*, jclass, jlong nativeBuilder, jboolean enabled) {
-    Builder* builder = (Builder*) nativeBuilder;
-    builder->panning(enabled);
-}
-
 extern "C" JNIEXPORT long Java_com_google_android_filament_utils_Manipulator_nBuilderBuild(JNIEnv*, jclass, jlong nativeBuilder, jint mode) {
     Builder* builder = (Builder*) nativeBuilder;
     return (jlong) builder->build((Mode) mode);

android/filament-utils-android/src/main/java/com/google/android/filament/utils/Manipulator.java

@@ -274,17 +274,6 @@ public class Manipulator {
             return this;
         }
 
-        /**
-         * Sets whether panning is enabled in the manipulator.
-         *
-         * @return this <code>Builder</code> object for chaining calls
-         */
-        @NonNull
-        public Builder panning(Boolean enabled) {
-            nBuilderPanning(mNativeBuilder, enabled);
-            return this;
-        }
-
         /**
          * Creates and returns the <code>Manipulator</code> object.
          *
@@ -494,7 +483,6 @@ public class Manipulator {
     private static native void nBuilderFlightPanSpeed(long nativeBuilder, float x, float y);
     private static native void nBuilderFlightMoveDamping(long nativeBuilder, float damping);
     private static native void nBuilderGroundPlane(long nativeBuilder, float a, float b, float c, float d);
-    private static native void nBuilderPanning(long nativeBuilder, Boolean enabled);
     private static native long nBuilderBuild(long nativeBuilder, int mode);
 
     private static native void nDestroyManipulator(long nativeManip);

android/gltfio-android/CMakeLists.txt

@@ -44,7 +44,6 @@ set_target_properties(uberarchive PROPERTIES IMPORTED_LOCATION
         ${FILAMENT_DIR}/lib/${ANDROID_ABI}/libuberarchive.a)
 
 set(CMAKE_SHARED_LINKER_FLAGS_RELEASE "${CMAKE_SHARED_LINKER_FLAGS_RELEASE} -Wl,--version-script=${CMAKE_CURRENT_SOURCE_DIR}/libgltfio-jni.map")
-set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} -Wl,-z,max-page-size=16384")
 
 set(GLTFIO_SRCS
         ${GLTFIO_DIR}/include/gltfio/Animator.h
@@ -87,10 +86,7 @@ set(GLTFIO_SRCS
         ${GLTFIO_DIR}/src/Wireframe.cpp
         ${GLTFIO_DIR}/src/Wireframe.h
         ${GLTFIO_DIR}/src/downcast.h
-        ${GLTFIO_DIR}/src/extended/AssetLoaderExtended.cpp
         ${GLTFIO_DIR}/src/extended/AssetLoaderExtended.h
-        ${GLTFIO_DIR}/src/extended/ResourceLoaderExtended.cpp
-        ${GLTFIO_DIR}/src/extended/ResourceLoaderExtended.h
         ${GLTFIO_DIR}/src/extended/TangentsJobExtended.cpp
         ${GLTFIO_DIR}/src/extended/TangentsJobExtended.h
         ${GLTFIO_DIR}/src/extended/TangentSpaceMeshWrapper.cpp
@@ -120,6 +116,7 @@ set(GLTFIO_INCLUDE_DIRS
         ../../third_party/cgltf
         ../../third_party/meshoptimizer/src
         ../../third_party/robin-map
+        ../../third_party/hat-trie
         ../../third_party/stb
         ../../libs/utils/include
         ../../libs/ktxreader/include

android/gradle.properties

@@ -1,5 +1,5 @@
 GROUP=com.google.android.filament
-VERSION_NAME=1.56.0
+VERSION_NAME=1.51.1
 
 POM_DESCRIPTION=Real-time physically based rendering engine for Android.
 

android/gradle/wrapper/gradle-wrapper.properties

@@ -1,6 +1,6 @@
 #Wed Nov 17 10:40:18 PST 2021
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-8.8-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.2-bin.zip
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists

android/samples/sample-gltf-viewer/build.gradle

@@ -6,10 +6,6 @@ plugins {
 
 project.ext.isSample = true
 
-kotlin {
-    jvmToolchain(versions.jdk)
-}
-
 filamentTools {
     cmgenArgs = "-q --format=ktx --size=256 --extract-blur=0.1 --deploy=src/main/assets/envs/default_env"
     iblInputFile = project.layout.projectDirectory.file("../../../third_party/environments/lightroom_14b.hdr")
@@ -17,7 +13,7 @@ filamentTools {
 }
 
 // don't forget to update MainACtivity.kt when/if changing this.
-tasks.register('copyMesh', Copy) {
+task copyMesh(type: Copy) {
     from "../../../third_party/models/BusterDrone"
     into "src/main/assets/models"
 }

android/samples/sample-hello-triangle/src/main/java/com/google/android/filament/hellotriangle/MainActivity.kt

@@ -112,13 +112,7 @@ class MainActivity : Activity() {
     }
 
     private fun setupFilament() {
-        val config = Engine.Config()
-        //config.forceGLES2Context = true
-
-        engine = Engine.Builder()
-            .config(config)
-            .featureLevel(Engine.FeatureLevel.FEATURE_LEVEL_0)
-            .build()
+        engine = Engine.Builder().featureLevel(Engine.FeatureLevel.FEATURE_LEVEL_0).build()
         renderer = engine.createRenderer()
         scene = engine.createScene()
         view = engine.createView()
@@ -129,9 +123,7 @@ class MainActivity : Activity() {
         scene.skybox = Skybox.Builder().color(0.035f, 0.035f, 0.035f, 1.0f).build(engine)
 
         // post-processing is not supported at feature level 0
-        if (engine.activeFeatureLevel == Engine.FeatureLevel.FEATURE_LEVEL_0) {
-            view.isPostProcessingEnabled = false
-        }
+        view.isPostProcessingEnabled = false
 
         // Tell the view which camera we want to use
         view.camera = camera
@@ -329,7 +321,7 @@ class MainActivity : Activity() {
             var flags = uiHelper.swapChainFlags
             if (engine.activeFeatureLevel == Engine.FeatureLevel.FEATURE_LEVEL_0) {
                 if (SwapChain.isSRGBSwapChainSupported(engine)) {
-                    flags = flags or SwapChainFlags.CONFIG_SRGB_COLORSPACE
+                    flags = flags or SwapChain.CONFIG_SRGB_COLORSPACE
                 }
             }
 

build.sh

@@ -44,6 +44,8 @@ function print_help {
     echo "        Exclude Vulkan support from the Android build."
     echo "    -s"
     echo "        Add iOS simulator support to the iOS build."
+    echo "    -t"
+    echo "        Enable SwiftShader support for Vulkan in desktop builds."
     echo "    -e"
     echo "        Enable EGL on Linux support for desktop builds."
     echo "    -l"
@@ -59,17 +61,6 @@ function print_help {
     echo "    -b"
     echo "        Enable Address and Undefined Behavior Sanitizers (asan/ubsan) for debugging."
     echo "        This is only for the desktop build."
-    echo "    -x value"
-    echo "        Define a preprocessor flag FILAMENT_BACKEND_DEBUG_FLAG with [value]. This is useful for"
-    echo "        enabling debug paths in the backend from the build script. For example, make a"
-    echo "        systrace-enabled build without directly changing #defines. Remember to add -f when"
-    echo "        changing this option."
-    echo "    -X osmesa_path"
-    echo "        Indicates a path to a completed OSMesa build. OSMesa is used to create an offscreen GL"
-    echo "        context for software rasterization"
-    echo "    -S type"
-    echo "        Enable stereoscopic rendering where type is one of [instanced|multiview]. This is only"
-    echo "        meant for building the samples."
     echo ""
     echo "Build types:"
     echo "    release"
@@ -169,6 +160,8 @@ INSTALL_COMMAND=
 VULKAN_ANDROID_OPTION="-DFILAMENT_SUPPORTS_VULKAN=ON"
 VULKAN_ANDROID_GRADLE_OPTION=""
 
+SWIFTSHADER_OPTION="-DFILAMENT_USE_SWIFTSHADER=OFF"
+
 EGL_ON_LINUX_OPTION="-DFILAMENT_SUPPORTS_EGL_ON_LINUX=OFF"
 
 MATDBG_OPTION="-DFILAMENT_ENABLE_MATDBG=OFF"
@@ -179,12 +172,6 @@ MATOPT_GRADLE_OPTION=""
 
 ASAN_UBSAN_OPTION=""
 
-BACKEND_DEBUG_FLAG_OPTION=""
-
-STEREOSCOPIC_OPTION=""
-
-OSMESA_OPTION=""
-
 IOS_BUILD_SIMULATOR=false
 BUILD_UNIVERSAL_LIBRARIES=false
 
@@ -239,13 +226,11 @@ function build_desktop_target {
             -DIMPORT_EXECUTABLES_DIR=out \
             -DCMAKE_BUILD_TYPE="$1" \
             -DCMAKE_INSTALL_PREFIX="../${lc_target}/filament" \
+            ${SWIFTSHADER_OPTION} \
             ${EGL_ON_LINUX_OPTION} \
             ${MATDBG_OPTION} \
             ${MATOPT_OPTION} \
             ${ASAN_UBSAN_OPTION} \
-            ${BACKEND_DEBUG_FLAG_OPTION} \
-            ${STEREOSCOPIC_OPTION} \
-            ${OSMESA_OPTION} \
             ${architectures} \
             ../..
         ln -sf "out/cmake-${lc_target}/compile_commands.json" \
@@ -304,7 +289,6 @@ function build_webgl_with_target {
             -DCMAKE_BUILD_TYPE="$1" \
             -DCMAKE_INSTALL_PREFIX="../webgl-${lc_target}/filament" \
             -DWEBGL=1 \
-            ${BACKEND_DEBUG_FLAG_OPTION} \
             ../..
         ln -sf "out/cmake-webgl-${lc_target}/compile_commands.json" \
            ../../compile_commands.json
@@ -379,8 +363,6 @@ function build_android_target {
             ${MATDBG_OPTION} \
             ${MATOPT_OPTION} \
             ${VULKAN_ANDROID_OPTION} \
-            ${BACKEND_DEBUG_FLAG_OPTION} \
-            ${STEREOSCOPIC_OPTION} \
             ../..
         ln -sf "out/cmake-android-${lc_target}-${arch}/compile_commands.json" \
            ../../compile_commands.json
@@ -534,7 +516,7 @@ function build_android {
             if [[ "${BUILD_ANDROID_SAMPLES}" == "true" ]]; then
                 for sample in ${ANDROID_SAMPLES}; do
                     echo "Installing out/${sample}-debug.apk"
-                    cp samples/${sample}/build/outputs/apk/debug/${sample}-debug.apk \
+                    cp samples/${sample}/build/outputs/apk/debug/${sample}-debug-unsigned.apk \
                         ../out/${sample}-debug.apk
                 done
             fi
@@ -615,7 +597,6 @@ function build_ios_target {
             -DCMAKE_TOOLCHAIN_FILE=../../third_party/clang/iOS.cmake \
             ${MATDBG_OPTION} \
             ${MATOPT_OPTION} \
-            ${STEREOSCOPIC_OPTION} \
             ../..
         ln -sf "out/cmake-ios-${lc_target}-${arch}/compile_commands.json" \
            ../../compile_commands.json
@@ -749,13 +730,6 @@ function validate_build_command {
             exit 1
         fi
     fi
-
-    # Make sure FILAMENT_BACKEND_DEBUG_FLAG is only meant for debug builds
-    if [[ "${ISSUE_DEBUG_BUILD}" != "true" ]] && [[ ! -z "${BACKEND_DEBUG_FLAG_OPTION}" ]]; then
-        echo "Error: cannot specify FILAMENT_BACKEND_DEBUG_FLAG in non-debug build"
-        exit 1
-    fi
-
     set -e
 }
 
@@ -802,7 +776,7 @@ function check_debug_release_build {
 
 pushd "$(dirname "$0")" > /dev/null
 
-while getopts ":hacCfgijmp:q:uvslwedk:bx:S:X:" opt; do
+while getopts ":hacCfgijmp:q:uvslwtedk:b" opt; do
     case ${opt} in
         h)
             print_help
@@ -866,7 +840,7 @@ while getopts ":hacCfgijmp:q:uvslwedk:bx:S:X:" opt; do
                         echo "Platform must be one of [desktop|android|ios|webgl|all]"
                         echo ""
                         exit 1
-                    ;;
+                    ;;    
                 esac
             done
             ;;
@@ -921,6 +895,10 @@ while getopts ":hacCfgijmp:q:uvslwedk:bx:S:X:" opt; do
             IOS_BUILD_SIMULATOR=true
             echo "iOS simulator support enabled."
             ;;
+        t)
+            SWIFTSHADER_OPTION="-DFILAMENT_USE_SWIFTSHADER=ON"
+            echo "SwiftShader support enabled."
+            ;;
         e)
             EGL_ON_LINUX_OPTION="-DFILAMENT_SUPPORTS_EGL_ON_LINUX=ON -DFILAMENT_SKIP_SDL2=ON -DFILAMENT_SKIP_SAMPLES=ON"
             echo "EGL on Linux support enabled; skipping SDL2."
@@ -940,24 +918,6 @@ while getopts ":hacCfgijmp:q:uvslwedk:bx:S:X:" opt; do
         b)  ASAN_UBSAN_OPTION="-DFILAMENT_ENABLE_ASAN_UBSAN=ON"
             echo "Enabled ASAN/UBSAN"
             ;;
-        x)  BACKEND_DEBUG_FLAG_OPTION="-DFILAMENT_BACKEND_DEBUG_FLAG=${OPTARG}"
-            ;;
-        S)  case $(echo "${OPTARG}" | tr '[:upper:]' '[:lower:]') in
-                instanced)
-                    STEREOSCOPIC_OPTION="-DFILAMENT_SAMPLES_STEREO_TYPE=instanced"
-                    ;;
-                multiview)
-                    STEREOSCOPIC_OPTION="-DFILAMENT_SAMPLES_STEREO_TYPE=multiview"
-                    ;;
-                *)
-                    echo "Unknown stereoscopic type ${OPTARG}"
-                    echo "Type must be one of [instanced|multiview]"
-                    echo ""
-                    exit 1
-            esac
-            ;;
-        X)  OSMESA_OPTION="-DFILAMENT_OSMESA_PATH=${OPTARG}"
-            ;;
         \?)
             echo "Invalid option: -${OPTARG}" >&2
             echo ""

build/android/build.sh

@@ -57,10 +57,15 @@ FILAMENT_NDK_VERSION=${FILAMENT_NDK_VERSION:-$(cat `dirname $0`/ndk.version)}
 
 # Install the required NDK version specifically (if not present)
 if [[ ! -d "${ANDROID_HOME}/ndk/$FILAMENT_NDK_VERSION" ]]; then
-    yes | ${ANDROID_HOME}/cmdline-tools/latest/bin/sdkmanager --licenses
-    ${ANDROID_HOME}/cmdline-tools/latest/bin/sdkmanager "ndk;$FILAMENT_NDK_VERSION"
+    ${ANDROID_HOME}/cmdline-tools/latest/bin/sdkmanager "ndk;$FILAMENT_NDK_VERSION" > /dev/null
 fi
+
+# Only build 1 64 bit target during presubmit to cut down build times during presubmit
+# Continuous builds will build everything
 ANDROID_ABIS=
+if [[ "$TARGET" == "presubmit" ]]; then
+  ANDROID_ABIS="-q arm64-v8a"
+fi
 
 # Build the Android sample-gltf-viewer APK during release.
 BUILD_SAMPLES=
@@ -68,19 +73,5 @@ if [[ "$TARGET" == "release" ]]; then
     BUILD_SAMPLES="-k sample-gltf-viewer"
 fi
 
-function build_android() {
-    local ABI=$1
-
-    # Do the following in two steps so that we do not run out of space
-    if [[ -n "${BUILD_DEBUG}" ]]; then
-        FILAMENT_NDK_VERSION=${FILAMENT_NDK_VERSION} ./build.sh -p android -q ${ABI} -c ${BUILD_SAMPLES} ${GENERATE_ARCHIVES} ${BUILD_DEBUG}
-        rm -rf out/cmake-android-debug-*
-    fi
-    if [[ -n "${BUILD_RELEASE}" ]]; then
-        FILAMENT_NDK_VERSION=${FILAMENT_NDK_VERSION} ./build.sh -p android -q ${ABI} -c ${BUILD_SAMPLES} ${GENERATE_ARCHIVES} ${BUILD_RELEASE}
-        rm -rf out/cmake-android-release-*
-    fi
-}
-
 pushd `dirname $0`/../.. > /dev/null
-build_android $2
+FILAMENT_NDK_VERSION=${FILAMENT_NDK_VERSION} ./build.sh -p android $ANDROID_ABIS -c $BUILD_SAMPLES $GENERATE_ARCHIVES $BUILD_DEBUG $BUILD_RELEASE

build/android/ndk.version

@@ -1 +1 @@
-27.0.11718014
+26.1.10909125

build/swiftshader/Dockerfile

@@ -0,0 +1,53 @@
+# Build the image:
+#   docker build --no-cache --tag ssfilament -f build/swiftshader/Dockerfile .
+#   docker tag ssfilament ghcr.io/filament-assets/swiftshader
+#
+# Publish the image:
+#   docker login ghcr.io --username <user> --password <token>
+#   docker push ghcr.io/filament-assets/swiftshader
+#
+# Run the image and mount the current directory:
+#   docker run -it -v `pwd`:/trees/filament -t ssfilament
+
+FROM ubuntu:focal
+WORKDIR /trees
+ARG DEBIAN_FRONTEND=noninteractive
+ENV SWIFTSHADER_LD_LIBRARY_PATH=/trees/swiftshader/build
+ENV CXXFLAGS='-fno-builtin -Wno-pass-failed'
+
+RUN apt-get update && \
+    apt-get --no-install-recommends install -y \
+	apt-transport-https \
+	apt-utils \
+	build-essential \
+	cmake \
+	ca-certificates \
+	git \
+	ninja-build \
+	python \
+	python3 \
+	xorg-dev \
+	clang-7 \
+	libc++-7-dev \
+	libc++abi-7-dev \
+	lldb
+
+# Ensure that clang is used instead of gcc.
+RUN set -eux ;\
+    update-alternatives --install /usr/bin/clang clang /usr/bin/clang-7 100 ;\
+    update-alternatives --install /usr/bin/clang++ clang++ /usr/bin/clang++-7 100 ;\
+    update-alternatives --install /usr/bin/cc cc /usr/bin/clang 100 ;\
+    update-alternatives --install /usr/bin/c++ c++ /usr/bin/clang++ 100
+
+# Get patch files from the local Filament tree.
+COPY build/swiftshader/*.diff .
+
+# Clone SwiftShader, apply patches, and build it.
+RUN set -eux ;\
+	git clone https://swiftshader.googlesource.com/SwiftShader swiftshader ;\
+    cd swiftshader ;\
+	git checkout 139f5c3 ;\
+	git apply /trees/*.diff ;\
+    cd build ;\
+    cmake .. -GNinja -DCMAKE_BUILD_TYPE=Release ;\
+    ninja

build/swiftshader/gallery.py

@@ -0,0 +1,56 @@
+#!/usr/bin/env python3
+
+from pathlib import Path
+import os
+
+spath = os.path.dirname(os.path.realpath(__file__))
+
+path = Path(spath)
+
+folder = "../../results/"
+
+images = list(path.glob(folder + '*.png'))
+
+images.sort()
+
+gallery = open(path.absolute().joinpath(folder + 'index.html'), 'w')
+
+gallery.write("""<html>
+<head>
+<script type="module" src="https://unpkg.com/img-comparison-slider@latest/dist/component/component.esm.js"></script>
+<script nomodule="" src="https://unpkg.com/img-comparison-slider@latest/dist/component/component.js"></script>
+<link rel="stylesheet" href="https://unpkg.com/img-comparison-slider@latest/dist/collection/styles/initial.css"/>
+<style>
+    h2 {
+        font-weight: normal;
+        margin-top: 150px;
+        margin-bottom: 20px;
+    }
+    a {
+        text-decoration: none;
+        font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
+        color: blue;
+    }
+    a:hover {
+        font-weight: bold;
+    }
+</style>
+</head>
+<body>
+""")
+
+tag = ''
+
+for image in images:
+    group = image.stem.rstrip('0123456789')
+    before = f'https://filament-assets.github.io/golden/{group}/{image.name}'
+    after = image.name
+    gallery.write('\n')
+    gallery.write(f'<h2><a href="{image.stem}.json">{image.stem}.json</a></h2>\n')
+    gallery.write('<img-comparison-slider>\n')
+    gallery.write(f'<img slot="before" src="{before}" /> <img slot="after" src="{after}" />\n')
+    gallery.write('</img-comparison-slider>\n')
+
+gallery.write("""</body>
+</html>
+""")

build/swiftshader/patch_00.diff

@@ -0,0 +1,62 @@
+diff --git a/src/Vulkan/VkPipeline.cpp b/src/Vulkan/VkPipeline.cpp
+index 86913ec72..3b35345af 100644
+--- a/src/Vulkan/VkPipeline.cpp
++++ b/src/Vulkan/VkPipeline.cpp
+@@ -71,7 +71,56 @@ std::vector<uint32_t> preprocessSpirv(
+ 	if(optimize)
+ 	{
+ 		// Full optimization list taken from spirv-opt.
+-		opt.RegisterPerformancePasses();
++
++		// We have removed CreateRedundancyEliminationPass because it segfaults when encountering:
++		//     %389 = OpCompositeConstruct %7 %386 %387 %388 %86
++		// When inserting an entry into instruction_to_value_ (which is an unordered_map)
++		// This could perhaps be investigated further with help from asan.
++
++		using namespace spvtools;
++		opt.RegisterPass(CreateWrapOpKillPass())
++			.RegisterPass(CreateDeadBranchElimPass())
++			.RegisterPass(CreateMergeReturnPass())
++			.RegisterPass(CreateInlineExhaustivePass())
++			.RegisterPass(CreateAggressiveDCEPass())
++			.RegisterPass(CreatePrivateToLocalPass())
++			.RegisterPass(CreateLocalSingleBlockLoadStoreElimPass())
++			.RegisterPass(CreateLocalSingleStoreElimPass())
++			.RegisterPass(CreateAggressiveDCEPass())
++			.RegisterPass(CreateScalarReplacementPass())
++			.RegisterPass(CreateLocalAccessChainConvertPass())
++			.RegisterPass(CreateLocalSingleBlockLoadStoreElimPass())
++			.RegisterPass(CreateLocalSingleStoreElimPass())
++			.RegisterPass(CreateAggressiveDCEPass())
++			.RegisterPass(CreateLocalMultiStoreElimPass())
++			.RegisterPass(CreateAggressiveDCEPass())
++			.RegisterPass(CreateCCPPass())
++			.RegisterPass(CreateAggressiveDCEPass())
++			.RegisterPass(CreateLoopUnrollPass(true))
++			.RegisterPass(CreateDeadBranchElimPass())
++			.RegisterPass(CreateRedundancyEliminationPass()) // workaround for SEGFAULT
++			.RegisterPass(CreateCombineAccessChainsPass())
++			.RegisterPass(CreateSimplificationPass())
++			.RegisterPass(CreateScalarReplacementPass())
++			.RegisterPass(CreateLocalAccessChainConvertPass())
++			.RegisterPass(CreateLocalSingleBlockLoadStoreElimPass())
++			.RegisterPass(CreateLocalSingleStoreElimPass())
++			.RegisterPass(CreateAggressiveDCEPass())
++			.RegisterPass(CreateSSARewritePass())
++			.RegisterPass(CreateAggressiveDCEPass())
++			.RegisterPass(CreateVectorDCEPass())
++			.RegisterPass(CreateDeadInsertElimPass())
++			.RegisterPass(CreateDeadBranchElimPass())
++			.RegisterPass(CreateSimplificationPass())
++			.RegisterPass(CreateIfConversionPass())
++			.RegisterPass(CreateCopyPropagateArraysPass())
++			.RegisterPass(CreateReduceLoadSizePass())
++			.RegisterPass(CreateAggressiveDCEPass())
++			.RegisterPass(CreateBlockMergePass())
++			.RegisterPass(CreateRedundancyEliminationPass()) // workaround for SEGFAULT
++			.RegisterPass(CreateDeadBranchElimPass())
++			.RegisterPass(CreateBlockMergePass())
++			.RegisterPass(CreateSimplificationPass());
+ 	}
+ 
+ 	std::vector<uint32_t> optimized;

build/swiftshader/test.sh

@@ -0,0 +1,127 @@
+#!/bin/bash
+set -e
+
+function print_help {
+    local self_name=$(basename "$0")
+    echo "This script issues docker commands for testing Filament with SwiftShader."
+    echo "The usual sequence of commands is: fetch, start, build filament release, and run."
+    echo ""
+    echo "Usage:"
+    echo "    $self_name [command]"
+    echo ""
+    echo "Commands:"
+    echo "    build filament [debug | release]"
+    echo "        Use the container to build Filament."
+    echo "    build swiftshader [debug | release]"
+    echo "        Use the container to do a clean rebuild of SwiftShader."
+    echo "        (Note that the container already has SwiftShader built.)"
+    echo "    fetch"
+    echo "        Download the docker image from the central repository."
+    echo "    help"
+    echo "        Print this help message."
+    echo "    logs"
+    echo "        Print messages from the container's kernel ring buffer."
+    echo "        This is useful for diagnosing OOM issues."
+    echo "    run [lldb]"
+    echo "        Launch a test inside the container, optionally via lldb."
+    echo "    shell"
+    echo "        Interact with a bash prompt in the container."
+    echo "    start"
+    echo "        Start a container from the image."
+    echo "    stop"
+    echo "        Stop the container."
+    echo ""
+}
+
+# Change the current working directory to the Filament root.
+pushd "$(dirname "$0")/../.." > /dev/null
+
+if [[ "$1" == "build" ]] && [[ "$2" == "filament" ]]; then
+    docker exec runner filament/build.sh -t $3 gltf_viewer
+    exit $?
+fi
+
+if [[ "$1" == "build" ]] && [[ "$2" == "swiftshader" ]]; then
+    BUILD_TYPE="$3"
+    BUILD_TYPE="$(tr '[:lower:]' '[:upper:]' <<< ${BUILD_TYPE:0:1})${BUILD_TYPE:1}"
+    docker exec --workdir /trees/swiftshader runner rm -rf build
+    docker exec --workdir /trees/swiftshader runner mkdir build
+    docker exec --workdir /trees/swiftshader/build runner cmake -GNinja -DCMAKE_BUILD_TYPE="$BUILD_TYPE" ..
+    docker exec --workdir /trees/swiftshader/build runner ninja
+    exit $?
+fi
+
+if [[ "$1" == "fetch" ]]; then
+    docker pull ghcr.io/filament-assets/swiftshader:latest
+    docker tag ghcr.io/filament-assets/swiftshader:latest ssfilament
+    exit $?
+fi
+
+if [[ "$1" == "help" ]]; then
+    print_help
+    exit 0
+fi
+
+if [[ "$1" == "logs" ]]; then
+    docker exec runner dmesg --human --read-clear
+    exit $?
+fi
+
+if [[ "$1" == "run" ]] && [[ "$2" == "lldb" ]]; then
+    docker exec -i --workdir /trees/filament/results runner \
+          lldb --batch -o run -o bt -- \
+          ../out/cmake-release/samples/gltf_viewer \
+          --headless \
+          --batch ../libs/viewer/tests/basic.json \
+          --api vulkan
+    docker exec runner /trees/filament/build/swiftshader/gallery.py
+    exit $?
+fi
+
+if [[ "$1" == "run" ]]; then
+    docker exec --tty  --workdir /trees/filament/results runner \
+          /usr/bin/catchsegv \
+          ../out/cmake-release/samples/gltf_viewer \
+          --headless \
+          --batch ../libs/viewer/tests/basic.json \
+          --api vulkan
+    docker exec runner /trees/filament/build/swiftshader/gallery.py
+    exit $?
+fi
+
+if [[ "$1" == "shell" ]]; then
+    docker exec --interactive --tty runner /bin/bash
+    exit $?
+fi
+
+# Notes on options being passed to docker's run command:
+#
+# - The memory constraint seems to prevent an OOM signal in GitHub Actions.
+# - The cap / security args allow use of lldb and creation of core dumps.
+# - The privileged arg allows use of dmesg for examining OOM logs.
+#
+# Currently, a GitHub Actions VM has 2 CPUs, 7 GB RAM, and 14 GB of SSD disk space.
+#
+# Please be aware that Docker Desktop might impose additional resource constraints, and that those
+# settings can only be controlled with its GUI. We recommend at least 7 GB of memory and 2 GB swap.
+if [[ "$1" == "start" ]]; then
+    mkdir -p results
+    docker run --tty --rm --detach --privileged \
+          --memory 6.5g \
+          --name runner \
+          --cap-add=SYS_PTRACE \
+          --security-opt seccomp=unconfined \
+          --security-opt apparmor=unconfined \
+          --volume `pwd`:/trees/filament \
+          --workdir /trees \
+          ssfilament
+    exit $?
+fi
+
+if [[ "$1" == "stop" ]]; then
+    docker container rm runner --force
+    exit $?
+fi
+
+print_help
+exit 1

build/web/ci-common.sh

@@ -1,6 +1,7 @@
 #!/bin/bash
 if [ `uname` == "Linux" ];then
-    source `dirname $0`/../linux/ci-common.sh
+    curl -OL https://github.com/ninja-build/ninja/releases/download/v1.10.2/ninja-linux.zip
+    unzip -q ninja-linux.zip
 elif [ `uname` == "Darwin" ];then
     curl -OL https://github.com/ninja-build/ninja/releases/download/v1.10.2/ninja-mac.zip
     unzip -q ninja-mac.zip
@@ -12,6 +13,9 @@ fi
 chmod +x ninja
 export PATH="$PWD:$PATH"
 
+# FIXME: kokoro machines have node and npm but currently they are symlinked to non-existent files
+# npm install -g typescript
+
 # Install emscripten.
 curl -L https://github.com/emscripten-core/emsdk/archive/refs/tags/3.1.15.zip > emsdk.zip
 unzip emsdk.zip ; mv emsdk-* emsdk ; cd emsdk

build/windows/build-github.bat

@@ -115,23 +115,17 @@ cmake ..\.. ^
     -DFILAMENT_SUPPORTS_VULKAN=ON ^
     || exit /b
 
-set build_flags=-j %NUMBER_OF_PROCESSORS%
-
-@echo on
-
-:: we've upgraded the windows machines, so the following are no longer accurate as of 09/19/24, but
-:: keeping around the comment for record.
-
 :: Attempt to fix "error C1060: compiler is out of heap space" seen on CI.
 :: Some resource libraries require significant heap space to compile, so first compile them serially.
-:: cmake --build . --target filagui --config %config% %build_flags% || exit /b
-:: cmake --build . --target uberarchive --config %config% %build_flags% || exit /b
-:: cmake --build . --target gltf-demo-resources --config %config% %build_flags% || exit /b
-:: cmake --build . --target filamentapp-resources --config %config% %build_flags% || exit /b
-:: cmake --build . --target sample-resources --config %config% %build_flags% || exit /b
-:: cmake --build . --target suzanne-resources --config %config% %build_flags% || exit /b
+@echo on
+cmake --build . --target filagui --config %config% || exit /b
+cmake --build . --target uberarchive --config %config% || exit /b
+cmake --build . --target gltf-demo-resources --config %config% || exit /b
+cmake --build . --target filamentapp-resources --config %config% || exit /b
+cmake --build . --target sample-resources --config %config% || exit /b
+cmake --build . --target suzanne-resources --config %config% || exit /b
 
-cmake --build . %INSTALL% --config %config% %build_flags% -- /m || exit /b
+cmake --build . %INSTALL% --config %config% -- /m || exit /b
 @echo off
 
 echo Disk info after building variant: %variant%

docs/Filament.html

@@ -476,7 +476,7 @@ Energy conservation is one of the key components of a good BRDF for physically b
 <p>
 
 
-For the specular term, \(f_r\) is a mirror BRDF that can be modeled with the Fresnel law, noted \(F\) in the Cook-Torrance approximation of the microfacet model integration:
+For the specular term, \(f_m\) is a mirror BRDF that can be modeled with the Fresnel law, noted \(F\) in the Cook-Torrance approximation of the microfacet model integration:
 
 </p><p>
 
@@ -857,7 +857,7 @@ The full GLSL implementation of the standard model is shown in <a href="#listing
 <span class="line">    <span class="hljs-comment">// perceptually linear roughness to roughness (see parameterization)</span></span>
 <span class="line">    <span class="hljs-type">float</span> roughness = perceptualRoughness * perceptualRoughness;</span>
 <span class="line"></span>
-<span class="line">    <span class="hljs-type">float</span> D = D_GGX(NoH, roughness);</span>
+<span class="line">    <span class="hljs-type">float</span> D = D_GGX(NoH, a);</span>
 <span class="line">    <span class="hljs-type">vec3</span>  F = F_Schlick(LoH, f0);</span>
 <span class="line">    <span class="hljs-type">float</span> V = V_SmithGGXCorrelated(NoV, NoL, roughness);</span>
 <span class="line"></span>

docs/Materials.md.html

@@ -1308,12 +1308,7 @@ Description
       declare a variable called `eyeDirection` you can access it in the fragment shader using
       `variable_eyeDirection`. In the vertex shader, the interpolant name is simply a member of
       the `MaterialVertexInputs` structure (`material.eyeDirection` in your example). Each
-      interpolant is of type `float4` (`vec4`) in the shaders. By default the precision of the
-      interpolant is `highp` in *both* the vertex and fragment shaders.
-      An alternate syntax can be used to specify both the name and precision of the interpolant.
-      In this case the specified precision is used as-is in both fragment and vertex stages, in
-      particular if `default` is specified the default precision is used is the fragment shader
-      (`mediump`) and in the vertex shader (`highp`).
+      interpolant is of type `float4` (`vec4`) in the shaders.
 
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ JSON
 material {
@@ -1325,11 +1320,7 @@ material {
         }
     ],
     variables : [
-         eyeDirection,
-         {
-            name : eyeColor,
-            precision : medium
-         }
+         eyeDirection
     ],
     vertexDomain : device,
     depthWrite : false,
@@ -1406,7 +1397,7 @@ Type
 :    `string`
 
 Value
-:     Any of `opaque`, `transparent`, `fade`, `add`, `masked`, `multiply`, `screen`, `custom`. Defaults to `opaque`.
+:     Any of `opaque`, `transparent`, `fade`, `add`, `masked`, `multiply`, `screen`. Defaults to `opaque`.
 
 Description
 :     Defines how/if the rendered object is blended with the content of the render target.
@@ -1429,7 +1420,6 @@ Description
       of the material's output defines whether a fragment is discarded or not. Additionally,
       ALPHA_TO_COVERAGE is enabled for non-translucent views. See the maskThreshold section for more
       information.
-    - **Custom**: blending is enabled. But the blending function is user specified. See `blendFunction`.
 
 !!! Note
     When `blending` is set to `masked`, alpha to coverage is automatically enabled for the material.
@@ -1442,36 +1432,6 @@ material {
 }
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
-### Blending and transparency: blendFunction
-
-Type
-:    `object`
-
-Fields
-:     `srcRGB`, `srcA`, `dstRGB`, `dstA`
-
-Description
-:       - *srcRGB*: source function applied to the RGB channels
-        - *srcA*: source function applied to the alpha channel
-        - *srcRGB*: destination function applied to the RGB channels
-        - *srcRGB*: destination function applied to the alpha channel
-        The values possible for each functions are one of `zero`, `one`, `srcColor`, `oneMinusSrcColor`,
-               `dstColor`, `oneMinusDstColor`, `srcAlpha`, `oneMinusSrcAlpha`, `dstAlpha`,
-               `oneMinusDstAlpha`, `srcAlphaSaturate`
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ JSON
-material {
-    blending : custom,
-    blendFunction :
-    {
-        srcRGB: one,
-        srcA: one,
-        dstRGB: oneMinusSrcColor,
-        dstA: oneMinusSrcAlpha
-    }
- }
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
 ### Blending and transparency: postLightingBlending
 
 Type
@@ -2434,7 +2394,6 @@ The following APIs are only available from the vertex block:
 **getWorldFromModelMatrix()**        | float4x4 |  Matrix that converts from model (object) space to world space
 **getWorldFromModelNormalMatrix()**  | float3x3 |  Matrix that converts normals from model (object) space to world space
 **getVertexIndex()**                 | int      |  Index of the current vertex
-**getEyeIndex()**                    | int      |  Index of the eye being rendered, starting at 0
 
 ### Fragment only
 

docs/viewer/index.html

@@ -43,7 +43,7 @@ filament-viewer::part(canvas) {
 </p>
 
 </main>
-<script src="https://unpkg.com/filament@1.51.6/filament.js"></script>
+<script src="https://unpkg.com/filament@1.44.0/filament.js"></script>
 <script src="https://unpkg.com/gltumble"></script>
 <script src="filament-viewer.js" type="module"></script>
 </body>

filament/CMakeLists.txt

@@ -61,12 +61,10 @@ set(SRCS
         src/Engine.cpp
         src/Exposure.cpp
         src/Fence.cpp
-        src/FilamentBuilder.cpp
         src/FrameInfo.cpp
         src/FrameSkipper.cpp
         src/Froxelizer.cpp
         src/Frustum.cpp
-        src/HwDescriptorSetLayoutFactory.cpp
         src/HwRenderPrimitiveFactory.cpp
         src/HwVertexBufferInfoFactory.cpp
         src/IndexBuffer.cpp
@@ -77,6 +75,8 @@ set(SRCS
         src/MaterialInstance.cpp
         src/MaterialParser.cpp
         src/MorphTargetBuffer.cpp
+        src/PerViewUniforms.cpp
+        src/PerShadowMapUniforms.cpp
         src/PostProcessManager.cpp
         src/RenderPass.cpp
         src/RenderPrimitive.cpp
@@ -125,12 +125,6 @@ set(SRCS
         src/details/Texture.cpp
         src/details/VertexBuffer.cpp
         src/details/View.cpp
-        src/ds/ColorPassDescriptorSet.cpp
-        src/ds/DescriptorSet.cpp
-        src/ds/DescriptorSetLayout.cpp
-        src/ds/PostProcessDescriptorSet.cpp
-        src/ds/ShadowMapDescriptorSet.cpp
-        src/ds/SsrPassDescriptorSet.cpp
         src/fg/Blackboard.cpp
         src/fg/DependencyGraph.cpp
         src/fg/FrameGraph.cpp
@@ -154,21 +148,22 @@ set(PRIVATE_HDRS
         src/FrameInfo.h
         src/FrameSkipper.h
         src/Froxelizer.h
-        src/HwDescriptorSetLayoutFactory.h
         src/HwRenderPrimitiveFactory.h
         src/HwVertexBufferInfoFactory.h
         src/Intersections.h
         src/MaterialParser.h
+        src/PerViewUniforms.h
+        src/PerShadowMapUniforms.h
         src/PIDController.h
         src/PostProcessManager.h
+        src/RendererUtils.h
         src/RenderPass.h
         src/RenderPrimitive.h
-        src/RendererUtils.h
         src/ResourceAllocator.h
         src/ResourceList.h
         src/ShadowMap.h
         src/ShadowMapManager.h
-        src/SharedHandle.h
+        src/TypedUniformBuffer.h
         src/UniformBuffer.h
         src/components/CameraManager.h
         src/components/LightManager.h
@@ -196,14 +191,6 @@ set(PRIVATE_HDRS
         src/details/Texture.h
         src/details/VertexBuffer.h
         src/details/View.h
-        src/downcast.h
-        src/ds/ColorPassDescriptorSet.h
-        src/ds/DescriptorSetLayout.h
-        src/ds/PostProcessDescriptorSet.h
-        src/ds/ShadowMapDescriptorSet.h
-        src/ds/SsrPassDescriptorSet.h
-        src/ds/TypedBuffer.h
-        src/ds/TypedUniformBuffer.h
         src/fg/Blackboard.h
         src/fg/FrameGraph.h
         src/fg/FrameGraphId.h
@@ -221,12 +208,12 @@ set(PRIVATE_HDRS
         src/materials/fsr/ffx_a.h
         src/materials/fsr/ffx_fsr1.h
         src/materials/fsr/ffx_fsr1_mobile.fs
+        src/downcast.h
 )
 
 set(MATERIAL_SRCS
         src/materials/antiAliasing/fxaa.mat
         src/materials/antiAliasing/taa.mat
-        src/materials/blitDepth.mat
         src/materials/blitLow.mat
         src/materials/blitArray.mat
         src/materials/bloom/bloomDownsample.mat
@@ -308,11 +295,6 @@ if (FILAMENT_ENABLE_MULTIVIEW)
     add_definitions(-DFILAMENT_ENABLE_MULTIVIEW)
 endif()
 
-# Whether to force the profiling mode.
-if (FILAMENT_FORCE_PROFILING_MODE)
-    add_definitions(-DFILAMENT_FORCE_PROFILING_MODE)
-endif()
-
 # ==================================================================================================
 # Definitions
 # ==================================================================================================
@@ -612,13 +594,6 @@ else()
             -Wover-aligned
             -Werror
     )
-    if (CMAKE_CXX_STANDARD EQUAL 20)
-        # The lambdas for passes in PostProcessManager.cpp capture this
-        # implicitly in a way that's deprecated in c++20, but can't easily be
-        # fixed in a way that's backwards compatible with c++17:
-        # https://www.nextptr.com/tutorial/ta1430524603/capture-this-in-lambda-expression-timeline-of-change
-        list(APPEND FILAMENT_WARNINGS -Wno-deprecated-this-capture)
-    endif()
 endif()
 
 target_compile_options(${TARGET} PRIVATE

filament/backend/CMakeLists.txt

@@ -12,7 +12,6 @@ set(PUBLIC_HDRS
         include/backend/AcquiredImage.h
         include/backend/BufferDescriptor.h
         include/backend/CallbackHandler.h
-        include/backend/DescriptorSetOffsetArray.h
         include/backend/DriverApiForward.h
         include/backend/DriverEnums.h
         include/backend/Handle.h
@@ -67,17 +66,11 @@ set(PRIVATE_HDRS
 # OpenGL / OpenGL ES Sources
 # ==================================================================================================
 
-if (FILAMENT_SUPPORTS_OPENGL AND NOT FILAMENT_USE_EXTERNAL_GLES3)
+if (FILAMENT_SUPPORTS_OPENGL AND NOT FILAMENT_USE_EXTERNAL_GLES3 AND NOT FILAMENT_USE_SWIFTSHADER)
     list(APPEND SRCS
             include/backend/platforms/OpenGLPlatform.h
-            src/opengl/BindingMap.h
             src/opengl/gl_headers.cpp
             src/opengl/gl_headers.h
-            src/opengl/GLBufferObject.h
-            src/opengl/GLDescriptorSet.cpp
-            src/opengl/GLDescriptorSet.h
-            src/opengl/GLDescriptorSetLayout.h
-            src/opengl/GLTexture.h
             src/opengl/GLUtils.cpp
             src/opengl/GLUtils.h
             src/opengl/OpenGLBlobCache.cpp
@@ -119,8 +112,6 @@ if (FILAMENT_SUPPORTS_OPENGL AND NOT FILAMENT_USE_EXTERNAL_GLES3)
             list(APPEND SRCS src/opengl/platforms/PlatformGLX.cpp)
         elseif (FILAMENT_SUPPORTS_EGL_ON_LINUX)
             list(APPEND SRCS src/opengl/platforms/PlatformEGLHeadless.cpp)
-        elseif (FILAMENT_SUPPORTS_OSMESA)
-            list(APPEND SRCS src/opengl/platforms/PlatformOSMesa.cpp)
         endif()
     elseif (WIN32)
         list(APPEND SRCS src/opengl/platforms/PlatformWGL.cpp)
@@ -175,22 +166,13 @@ endif()
 if (FILAMENT_SUPPORTS_VULKAN)
     list(APPEND SRCS
             include/backend/platforms/VulkanPlatform.h
-            src/vulkan/caching/VulkanDescriptorSetManager.cpp
-            src/vulkan/caching/VulkanDescriptorSetManager.h
-            src/vulkan/caching/VulkanPipelineLayoutCache.cpp
-            src/vulkan/caching/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/caching/VulkanDescriptorSet.cpp
+            src/vulkan/caching/VulkanDescriptorSet.h
             src/vulkan/platform/VulkanPlatform.cpp
             src/vulkan/platform/VulkanPlatformSwapChainImpl.cpp
             src/vulkan/platform/VulkanPlatformSwapChainImpl.h
             src/vulkan/spirv/VulkanSpirvUtils.cpp
             src/vulkan/spirv/VulkanSpirvUtils.h
-            src/vulkan/VulkanAsyncHandles.cpp
-            src/vulkan/VulkanAsyncHandles.h
             src/vulkan/VulkanBlitter.cpp
             src/vulkan/VulkanBlitter.h
             src/vulkan/VulkanBuffer.cpp
@@ -221,6 +203,9 @@ if (FILAMENT_SUPPORTS_VULKAN)
             src/vulkan/VulkanSwapChain.h
             src/vulkan/VulkanReadPixels.cpp
             src/vulkan/VulkanReadPixels.h
+            src/vulkan/VulkanResourceAllocator.h
+            src/vulkan/VulkanResources.cpp
+            src/vulkan/VulkanResources.h
             src/vulkan/VulkanTexture.cpp
             src/vulkan/VulkanTexture.h
             src/vulkan/VulkanUtility.cpp
@@ -372,11 +357,6 @@ set(LINUX_LINKER_OPTIMIZATION_FLAGS
         -Wl,--exclude-libs,bluegl
 )
 
-if (LINUX AND FILAMENT_SUPPORTS_OSMESA)
-    set(OSMESA_COMPILE_FLAGS
-        -I${FILAMENT_OSMESA_PATH}/include/GL)
-endif()
-
 if (MSVC)
     set(FILAMENT_WARNINGS /W3)
 else()
@@ -388,9 +368,6 @@ else()
             -Wover-aligned
             -Werror
     )
-    if (CMAKE_CXX_STANDARD EQUAL 20)
-        list(APPEND FILAMENT_WARNINGS -Wno-deprecated-this-capture)
-    endif()
 endif()
 
 if (APPLE)
@@ -400,7 +377,6 @@ endif()
 
 target_compile_options(${TARGET} PRIVATE
         ${FILAMENT_WARNINGS}
-        ${OSMESA_COMPILE_FLAGS}
         $<$<CONFIG:Release>:${OPTIMIZATION_FLAGS}>
         $<$<AND:$<PLATFORM_ID:Darwin>,$<CONFIG:Release>>:${DARWIN_OPTIMIZATION_FLAGS}>
 )
@@ -410,7 +386,6 @@ if (FILAMENT_SUPPORTS_METAL)
 endif()
 
 target_link_libraries(${TARGET} PRIVATE
-        ${OSMESA_LINKER_FLAGS}
         $<$<AND:$<PLATFORM_ID:Linux>,$<CONFIG:Release>>:${LINUX_LINKER_OPTIMIZATION_FLAGS}>
 )
 
@@ -438,14 +413,11 @@ if (APPLE OR LINUX)
         test/test_MissingRequiredAttributes.cpp
         test/test_ReadPixels.cpp
         test/test_BufferUpdates.cpp
-        test/test_Callbacks.cpp
         test/test_MRT.cpp
-        test/test_PushConstants.cpp
         test/test_LoadImage.cpp
         test/test_StencilBuffer.cpp
         test/test_Scissor.cpp
         test/test_MipLevels.cpp
-        test/test_Handles.cpp
     )
     set(BACKEND_TEST_LIBS
         backend
@@ -502,10 +474,6 @@ if (APPLE)
        # 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)
-
-       # This is needed after XCode 15.3
-       set_target_properties(backend_test_mac PROPERTIES BUILD_WITH_INSTALL_RPATH TRUE)
-       set_target_properties(backend_test_mac PROPERTIES INSTALL_RPATH /usr/local/lib)
     endif()
 endif()
 
@@ -517,40 +485,21 @@ endif()
 
 # ==================================================================================================
 # Compute tests
-#
-#if (NOT IOS AND NOT WEBGL)
-#
-#add_executable(compute_test
-#        test/ComputeTest.cpp
-#        test/Arguments.cpp
-#        test/test_ComputeBasic.cpp
-#        )
-#
-#target_link_libraries(compute_test PRIVATE
-#        backend
-#        getopt
-#        gtest
-#        )
-#
-#set_target_properties(compute_test PROPERTIES FOLDER Tests)
-#
-#endif()
 
-# ==================================================================================================
-# Metal utils tests
+if (NOT IOS AND NOT WEBGL)
 
-if (APPLE AND NOT IOS)
+add_executable(compute_test
+        test/ComputeTest.cpp
+        test/Arguments.cpp
+        test/test_ComputeBasic.cpp
+        )
 
-add_executable(metal_utils_test test/MetalTest.mm)
-
-target_compile_options(metal_utils_test PRIVATE "-fobjc-arc")
-
-target_link_libraries(metal_utils_test PRIVATE
+target_link_libraries(compute_test PRIVATE
         backend
         getopt
         gtest
         )
 
-set_target_properties(metal_utils_test PROPERTIES FOLDER Tests)
+set_target_properties(compute_test PROPERTIES FOLDER Tests)
 
 endif()

filament/backend/include/backend/DescriptorSetOffsetArray.h

@@ -1,101 +0,0 @@
-/*
- * Copyright (C) 2024 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_COMMANDSTREAMVECTOR_H
-#define TNT_FILAMENT_BACKEND_COMMANDSTREAMVECTOR_H
-
-#include <backend/DriverApiForward.h>
-
-#include <initializer_list>
-#include <memory>
-
-#include <stddef.h>
-#include <stdint.h>
-
-
-namespace filament::backend {
-
-void* allocateFromCommandStream(DriverApi& driver, size_t size, size_t alignment) noexcept;
-
-class DescriptorSetOffsetArray {
-public:
-    using value_type = uint32_t;
-    using reference = value_type&;
-    using const_reference = value_type const&;
-    using size_type = uint32_t;
-    using difference_type = int32_t;
-    using pointer = value_type*;
-    using const_pointer = value_type const*;
-    using iterator = pointer;
-    using const_iterator = const_pointer;
-
-    DescriptorSetOffsetArray() noexcept = default;
-
-    ~DescriptorSetOffsetArray() noexcept = default;
-
-    DescriptorSetOffsetArray(size_type size, DriverApi& driver) noexcept {
-        mOffsets = (value_type *)allocateFromCommandStream(driver,
-                size * sizeof(value_type), alignof(value_type));
-        std::uninitialized_fill_n(mOffsets, size, 0);
-    }
-
-    DescriptorSetOffsetArray(std::initializer_list<uint32_t> list, DriverApi& driver) noexcept {
-        mOffsets = (value_type *)allocateFromCommandStream(driver,
-                list.size() * sizeof(value_type), alignof(value_type));
-        std::uninitialized_copy(list.begin(), list.end(), mOffsets);
-    }
-
-    DescriptorSetOffsetArray(DescriptorSetOffsetArray const&) = delete;
-    DescriptorSetOffsetArray& operator=(DescriptorSetOffsetArray const&) = delete;
-
-    DescriptorSetOffsetArray(DescriptorSetOffsetArray&& rhs) noexcept
-            : mOffsets(rhs.mOffsets) {
-        rhs.mOffsets = nullptr;
-    }
-
-    DescriptorSetOffsetArray& operator=(DescriptorSetOffsetArray&& rhs) noexcept {
-        if (this != &rhs) {
-            mOffsets = rhs.mOffsets;
-            rhs.mOffsets = nullptr;
-        }
-        return *this;
-    }
-
-    bool empty() const noexcept { return mOffsets == nullptr; }
-
-    value_type* data() noexcept { return mOffsets; }
-    const value_type* data() const noexcept { return mOffsets; }
-
-
-    reference operator[](size_type n) noexcept {
-        return *(data() + n);
-    }
-
-    const_reference operator[](size_type n) const noexcept {
-        return *(data() + n);
-    }
-
-    void clear() noexcept {
-        mOffsets = nullptr;
-    }
-
-private:
-    value_type *mOffsets = nullptr;
-};
-
-} // namespace filament::backend
-
-#endif //TNT_FILAMENT_BACKEND_COMMANDSTREAMVECTOR_H

filament/backend/include/backend/DriverEnums.h

@@ -19,23 +19,17 @@
 #ifndef TNT_FILAMENT_BACKEND_DRIVERENUMS_H
 #define TNT_FILAMENT_BACKEND_DRIVERENUMS_H
 
+#include <utils/BitmaskEnum.h>
 #include <utils/unwindows.h> // Because we define ERROR in the FenceStatus enum.
 
-#include <backend/Platform.h>
 #include <backend/PresentCallable.h>
 
-#include <utils/BitmaskEnum.h>
-#include <utils/FixedCapacityVector.h>
-#include <utils/Invocable.h>
-#include <utils/compiler.h>
-#include <utils/debug.h>
 #include <utils/ostream.h>
 
 #include <math/vec4.h>
 
 #include <array>        // FIXME: STL headers are not allowed in public headers
 #include <type_traits>  // FIXME: STL headers are not allowed in public headers
-#include <variant>      // FIXME: STL headers are not allowed in public headers
 
 #include <stddef.h>
 #include <stdint.h>
@@ -96,16 +90,11 @@ static constexpr uint64_t SWAP_CHAIN_HAS_STENCIL_BUFFER         = SWAP_CHAIN_CON
  */
 static constexpr uint64_t SWAP_CHAIN_CONFIG_PROTECTED_CONTENT   = 0x40;
 
+
 static constexpr size_t MAX_VERTEX_ATTRIBUTE_COUNT  = 16;   // This is guaranteed by OpenGL ES.
 static constexpr size_t MAX_SAMPLER_COUNT           = 62;   // Maximum needed at feature level 3.
 static constexpr size_t MAX_VERTEX_BUFFER_COUNT     = 16;   // Max number of bound buffer objects.
 static constexpr size_t MAX_SSBO_COUNT              = 4;    // This is guaranteed by OpenGL ES.
-static constexpr size_t MAX_DESCRIPTOR_SET_COUNT    = 4;    // This is guaranteed by Vulkan.
-static constexpr size_t MAX_DESCRIPTOR_COUNT        = 64;   // per set
-
-static constexpr size_t MAX_PUSH_CONSTANT_COUNT     = 32;   // Vulkan 1.1 spec allows for 128-byte
-                                                            // of push constant (we assume 4-byte
-                                                            // types).
 
 // Per feature level caps
 // Use (int)FeatureLevel to index this array
@@ -123,7 +112,7 @@ static_assert(MAX_VERTEX_BUFFER_COUNT <= MAX_VERTEX_ATTRIBUTE_COUNT,
         "The number of buffer objects that can be attached to a VertexBuffer must be "
         "less than or equal to the maximum number of vertex attributes.");
 
-static constexpr size_t CONFIG_UNIFORM_BINDING_COUNT = 9;   // This is guaranteed by OpenGL ES.
+static constexpr size_t CONFIG_UNIFORM_BINDING_COUNT = 10;  // This is guaranteed by OpenGL ES.
 static constexpr size_t CONFIG_SAMPLER_BINDING_COUNT = 4;   // This is guaranteed by OpenGL ES.
 
 /**
@@ -169,16 +158,14 @@ static constexpr const char* backendToString(Backend backend) {
 }
 
 /**
- * Defines the shader language. Similar to the above backend enum, with some differences:
- * - The OpenGL backend can select between two shader languages: ESSL 1.0 and ESSL 3.0.
- * - The Metal backend can prefer precompiled Metal libraries, while falling back to MSL.
+ * Defines the shader language. Similar to the above backend enum, but the OpenGL backend can select
+ * between two shader languages: ESSL 1.0 and ESSL 3.0.
  */
 enum class ShaderLanguage {
     ESSL1 = 0,
     ESSL3 = 1,
     SPIRV = 2,
     MSL = 3,
-    METAL_LIBRARY = 4,
 };
 
 static constexpr const char* shaderLanguageToString(ShaderLanguage shaderLanguage) {
@@ -191,76 +178,9 @@ static constexpr const char* shaderLanguageToString(ShaderLanguage shaderLanguag
             return "SPIR-V";
         case ShaderLanguage::MSL:
             return "MSL";
-        case ShaderLanguage::METAL_LIBRARY:
-            return "Metal precompiled library";
     }
 }
 
-enum class ShaderStage : uint8_t {
-    VERTEX = 0,
-    FRAGMENT = 1,
-    COMPUTE = 2
-};
-
-static constexpr size_t PIPELINE_STAGE_COUNT = 2;
-enum class ShaderStageFlags : uint8_t {
-    NONE        =    0,
-    VERTEX      =    0x1,
-    FRAGMENT    =    0x2,
-    COMPUTE     =    0x4,
-    ALL_SHADER_STAGE_FLAGS = VERTEX | FRAGMENT | COMPUTE
-};
-
-static inline constexpr bool hasShaderType(ShaderStageFlags flags, ShaderStage type) noexcept {
-    switch (type) {
-        case ShaderStage::VERTEX:
-            return bool(uint8_t(flags) & uint8_t(ShaderStageFlags::VERTEX));
-        case ShaderStage::FRAGMENT:
-            return bool(uint8_t(flags) & uint8_t(ShaderStageFlags::FRAGMENT));
-        case ShaderStage::COMPUTE:
-            return bool(uint8_t(flags) & uint8_t(ShaderStageFlags::COMPUTE));
-    }
-}
-
-enum class DescriptorType : uint8_t {
-    UNIFORM_BUFFER,
-    SHADER_STORAGE_BUFFER,
-    SAMPLER,
-    INPUT_ATTACHMENT,
-    SAMPLER_EXTERNAL
-};
-
-enum class DescriptorFlags : uint8_t {
-    NONE = 0x00,
-    DYNAMIC_OFFSET = 0x01
-};
-
-using descriptor_set_t = uint8_t;
-
-using descriptor_binding_t = uint8_t;
-
-struct DescriptorSetLayoutBinding {
-    DescriptorType type;
-    ShaderStageFlags stageFlags;
-    descriptor_binding_t binding;
-    DescriptorFlags flags = DescriptorFlags::NONE;
-    uint16_t count = 0;
-
-    friend inline bool operator==(
-            DescriptorSetLayoutBinding const& lhs,
-            DescriptorSetLayoutBinding const& rhs) noexcept {
-        return lhs.type == rhs.type &&
-               lhs.flags == rhs.flags &&
-               lhs.count == rhs.count &&
-               lhs.stageFlags == rhs.stageFlags;
-    }
-};
-
-struct DescriptorSetLayout {
-    utils::FixedCapacityVector<DescriptorSetLayoutBinding> bindings;
-};
-
-
 /**
  * Bitmask for selecting render buffers
  */
@@ -319,20 +239,9 @@ struct Viewport {
     int32_t right() const noexcept { return left + int32_t(width); }
     //! get the top coordinate in window space of the viewport
     int32_t top() const noexcept { return bottom + int32_t(height); }
-
-    friend bool operator==(Viewport const& lhs, Viewport const& rhs) noexcept {
-        // clang can do this branchless with xor/or
-        return lhs.left == rhs.left && lhs.bottom == rhs.bottom &&
-               lhs.width == rhs.width && lhs.height == rhs.height;
-    }
-
-    friend bool operator!=(Viewport const& lhs, Viewport const& rhs) noexcept {
-        // clang is being dumb and uses branches
-        return bool(((lhs.left ^ rhs.left) | (lhs.bottom ^ rhs.bottom)) |
-                    ((lhs.width ^ rhs.width) | (lhs.height ^ rhs.height)));
-    }
 };
 
+
 /**
  * Specifies the mapping of the near and far clipping plane to window coordinates.
  */
@@ -351,6 +260,15 @@ enum class FenceStatus : int8_t {
     TIMEOUT_EXPIRED = 1,        //!< wait()'s timeout expired. The Fence condition is not satisfied.
 };
 
+/**
+ * Status codes for sync objects
+ */
+enum class SyncStatus : int8_t {
+    ERROR = -1,          //!< An error occurred. The Sync is not signaled.
+    SIGNALED = 0,        //!< The Sync is signaled.
+    NOT_SIGNALED = 1,    //!< The Sync is not signaled yet
+};
+
 static constexpr uint64_t FENCE_WAIT_FOR_EVER = uint64_t(-1);
 
 /**
@@ -409,7 +327,7 @@ enum class UniformType : uint8_t {
 /**
  * Supported constant parameter types
  */
-enum class ConstantType : uint8_t {
+ enum class ConstantType : uint8_t {
   INT,
   FLOAT,
   BOOL
@@ -440,18 +358,6 @@ enum class SamplerType : uint8_t {
     SAMPLER_CUBEMAP_ARRAY,  //!< Cube map array texture (feature level 2)
 };
 
-inline const char* stringify(SamplerType samplerType) {
-    switch (samplerType) {
-        case SamplerType::SAMPLER_2D: return "SAMPLER_2D";
-        case SamplerType::SAMPLER_2D_ARRAY: return "SAMPLER_2D_ARRAY";
-        case SamplerType::SAMPLER_CUBEMAP: return "SAMPLER_CUBEMAP";
-        case SamplerType::SAMPLER_EXTERNAL: return "SAMPLER_EXTERNAL";
-        case SamplerType::SAMPLER_3D: return "SAMPLER_3D";
-        case SamplerType::SAMPLER_CUBEMAP_ARRAY: return "SAMPLER_CUBEMAP_ARRAY";
-    }
-    return "UNKNOWN";
-}
-
 //! Subpass type
 enum class SubpassType : uint8_t {
     SUBPASS_INPUT
@@ -776,28 +682,10 @@ enum class TextureUsage : uint16_t {
     SUBPASS_INPUT       = 0x0020,            //!< Texture can be used as a subpass input
     BLIT_SRC            = 0x0040,            //!< Texture can be used the source of a blit()
     BLIT_DST            = 0x0080,            //!< Texture can be used the destination of a blit()
-    PROTECTED           = 0x0100,            //!< Texture can be used for protected content
-    DEFAULT             = UPLOADABLE | SAMPLEABLE,   //!< Default texture usage
-    ALL_ATTACHMENTS     = COLOR_ATTACHMENT | DEPTH_ATTACHMENT | STENCIL_ATTACHMENT | SUBPASS_INPUT,   //!< Mask of all attachments
+    PROTECTED           = 0x0100,            //!< Texture can be used the destination of a blit()
+    DEFAULT             = UPLOADABLE | SAMPLEABLE   //!< Default texture usage
 };
 
-inline const char* stringify(TextureUsage usage) {
-    switch (usage) {
-        case TextureUsage::NONE: return "NONE";
-        case TextureUsage::COLOR_ATTACHMENT: return "COLOR_ATTACHMENT";
-        case TextureUsage::DEPTH_ATTACHMENT: return "DEPTH_ATTACHMENT";
-        case TextureUsage::STENCIL_ATTACHMENT: return "STENCIL_ATTACHMENT";
-        case TextureUsage::UPLOADABLE: return "UPLOADABLE";
-        case TextureUsage::SAMPLEABLE: return "SAMPLEABLE";
-        case TextureUsage::SUBPASS_INPUT: return "SUBPASS_INPUT";
-        case TextureUsage::BLIT_SRC: return "BLIT_SRC";
-        case TextureUsage::BLIT_DST: return "BLIT_DST";
-        case TextureUsage::PROTECTED: return "PROTECTED";
-        case TextureUsage::DEFAULT: return "DEFAULT";
-        default: return "UNKNOWN";
-    }
-}
-
 //! Texture swizzle
 enum class TextureSwizzle : uint8_t {
     SUBSTITUTE_ZERO,
@@ -989,9 +877,6 @@ struct SamplerParams { // NOLINT
 
     struct EqualTo {
         bool operator()(SamplerParams lhs, SamplerParams rhs) const noexcept {
-            assert_invariant(lhs.padding0 == 0);
-            assert_invariant(lhs.padding1 == 0);
-            assert_invariant(lhs.padding2 == 0);
             auto* pLhs = reinterpret_cast<uint32_t const*>(reinterpret_cast<char const*>(&lhs));
             auto* pRhs = reinterpret_cast<uint32_t const*>(reinterpret_cast<char const*>(&rhs));
             return *pLhs == *pRhs;
@@ -1000,9 +885,6 @@ struct SamplerParams { // NOLINT
 
     struct LessThan {
         bool operator()(SamplerParams lhs, SamplerParams rhs) const noexcept {
-            assert_invariant(lhs.padding0 == 0);
-            assert_invariant(lhs.padding1 == 0);
-            assert_invariant(lhs.padding2 == 0);
             auto* pLhs = reinterpret_cast<uint32_t const*>(reinterpret_cast<char const*>(&lhs));
             auto* pRhs = reinterpret_cast<uint32_t const*>(reinterpret_cast<char const*>(&rhs));
             return *pLhs == *pRhs;
@@ -1010,12 +892,6 @@ struct SamplerParams { // NOLINT
     };
 
 private:
-    friend inline bool operator == (SamplerParams lhs, SamplerParams rhs) noexcept {
-        return SamplerParams::EqualTo{}(lhs, rhs);
-    }
-    friend inline bool operator != (SamplerParams lhs, SamplerParams rhs) noexcept {
-        return  !SamplerParams::EqualTo{}(lhs, rhs);
-    }
     friend inline bool operator < (SamplerParams lhs, SamplerParams rhs) noexcept {
         return SamplerParams::LessThan{}(lhs, rhs);
     }
@@ -1172,7 +1048,7 @@ struct RasterState {
             bool inverseFrontFaces                      : 1;        // 31
 
             //! padding, must be 0
-            bool depthClamp                             : 1;        // 32
+            uint8_t padding                             : 1;        // 32
         };
         uint32_t u = 0;
     };
@@ -1183,6 +1059,32 @@ struct RasterState {
  * \privatesection
  */
 
+enum class ShaderStage : uint8_t {
+    VERTEX = 0,
+    FRAGMENT = 1,
+    COMPUTE = 2
+};
+
+static constexpr size_t PIPELINE_STAGE_COUNT = 2;
+enum class ShaderStageFlags : uint8_t {
+    NONE        =    0,
+    VERTEX      =    0x1,
+    FRAGMENT    =    0x2,
+    COMPUTE     =    0x4,
+    ALL_SHADER_STAGE_FLAGS = VERTEX | FRAGMENT | COMPUTE
+};
+
+static inline constexpr bool hasShaderType(ShaderStageFlags flags, ShaderStage type) noexcept {
+    switch (type) {
+        case ShaderStage::VERTEX:
+            return bool(uint8_t(flags) & uint8_t(ShaderStageFlags::VERTEX));
+        case ShaderStage::FRAGMENT:
+            return bool(uint8_t(flags) & uint8_t(ShaderStageFlags::FRAGMENT));
+        case ShaderStage::COMPUTE:
+            return bool(uint8_t(flags) & uint8_t(ShaderStageFlags::COMPUTE));
+    }
+}
+
 /**
  * Selects which buffers to clear at the beginning of the render pass, as well as which buffers
  * can be discarded at the beginning and end of the render pass.
@@ -1312,15 +1214,13 @@ struct StencilState {
     uint8_t padding = 0;
 };
 
-using PushConstantVariant = std::variant<int32_t, float, bool>;
-
 static_assert(sizeof(StencilState::StencilOperations) == 5u,
         "StencilOperations size not what was intended");
 
 static_assert(sizeof(StencilState) == 12u,
         "StencilState size not what was intended");
 
-using FrameScheduledCallback = utils::Invocable<void(backend::PresentCallable)>;
+using FrameScheduledCallback = void(*)(PresentCallable callable, void* user);
 
 enum class Workaround : uint16_t {
     // The EASU pass must split because shader compiler flattens early-exit branch
@@ -1332,14 +1232,23 @@ enum class Workaround : uint16_t {
     ADRENO_UNIFORM_ARRAY_CRASH,
     // Workaround a Metal pipeline compilation error with the message:
     // "Could not statically determine the target of a texture". See light_indirect.fs
-    METAL_STATIC_TEXTURE_TARGET_ERROR,
+    A8X_STATIC_TEXTURE_TARGET_ERROR,
     // Adreno drivers sometimes aren't able to blit into a layer of a texture array.
     DISABLE_BLIT_INTO_TEXTURE_ARRAY,
     // Multiple workarounds needed for PowerVR GPUs
     POWER_VR_SHADER_WORKAROUNDS,
+    // The driver has some threads pinned, and we can't easily know on which core, it can hurt
+    // performance more if we end-up pinned on the same one.
+    DISABLE_THREAD_AFFINITY
 };
 
-using StereoscopicType = backend::Platform::StereoscopicType;
+//! The type of technique for stereoscopic rendering
+enum class StereoscopicType : uint8_t {
+    // Stereoscopic rendering is performed using instanced rendering technique.
+    INSTANCED,
+    // Stereoscopic rendering is performed using the multiview feature from the graphics backend.
+    MULTIVIEW,
+};
 
 } // namespace filament::backend
 
@@ -1347,8 +1256,6 @@ template<> struct utils::EnableBitMaskOperators<filament::backend::ShaderStageFl
         : public std::true_type {};
 template<> struct utils::EnableBitMaskOperators<filament::backend::TargetBufferFlags>
         : public std::true_type {};
-template<> struct utils::EnableBitMaskOperators<filament::backend::DescriptorFlags>
-        : public std::true_type {};
 template<> struct utils::EnableBitMaskOperators<filament::backend::TextureUsage>
         : public std::true_type {};
 template<> struct utils::EnableBitMaskOperators<filament::backend::StencilFace>

filament/backend/include/backend/Handle.h

@@ -23,7 +23,6 @@
 #include <utils/debug.h>
 
 #include <type_traits> // FIXME: STL headers are not allowed in public headers
-#include <utility>
 
 #include <stdint.h>
 
@@ -42,8 +41,6 @@ struct HwTexture;
 struct HwTimerQuery;
 struct HwVertexBufferInfo;
 struct HwVertexBuffer;
-struct HwDescriptorSetLayout;
-struct HwDescriptorSet;
 
 /*
  * A handle to a backend resource. HandleBase is for internal use only.
@@ -78,19 +75,6 @@ protected:
     HandleBase(HandleBase const& rhs) noexcept = default;
     HandleBase& operator=(HandleBase const& rhs) noexcept = default;
 
-    HandleBase(HandleBase&& rhs) noexcept
-            : object(rhs.object) {
-        rhs.object = nullid;
-    }
-
-    HandleBase& operator=(HandleBase&& rhs) noexcept {
-        if (this != &rhs) {
-            object = rhs.object;
-            rhs.object = nullid;
-        }
-        return *this;
-    }
-
 private:
     HandleId object;
 };
@@ -105,20 +89,8 @@ struct Handle : public HandleBase {
     Handle() noexcept = default;
 
     Handle(Handle const& rhs) noexcept = default;
-    Handle(Handle&& rhs) noexcept = default;
 
-    // Explicitly redefine copy/move assignment operators rather than just using default here.
-    // Because it doesn't make a call to the parent's method automatically during the std::move
-    // function call(https://en.cppreference.com/w/cpp/algorithm/move) in certain compilers like
-    // NDK 25.1.8937393 and below (see b/371980551)
-    Handle& operator=(Handle const& rhs) noexcept {
-        HandleBase::operator=(rhs);
-        return *this;
-    }
-    Handle& operator=(Handle&& rhs) noexcept {
-        HandleBase::operator=(std::move(rhs));
-        return *this;
-    }
+    Handle& operator=(Handle const& rhs) noexcept = default;
 
     explicit Handle(HandleId id) noexcept : HandleBase(id) { }
 
@@ -143,21 +115,19 @@ private:
 
 // Types used by the command stream
 // (we use this renaming because the macro-system doesn't deal well with "<" and ">")
-using BufferObjectHandle        = Handle<HwBufferObject>;
-using FenceHandle               = Handle<HwFence>;
-using IndexBufferHandle         = Handle<HwIndexBuffer>;
-using ProgramHandle             = Handle<HwProgram>;
-using RenderPrimitiveHandle     = Handle<HwRenderPrimitive>;
-using RenderTargetHandle        = Handle<HwRenderTarget>;
-using SamplerGroupHandle        = Handle<HwSamplerGroup>;
-using StreamHandle              = Handle<HwStream>;
-using SwapChainHandle           = Handle<HwSwapChain>;
-using TextureHandle             = Handle<HwTexture>;
-using TimerQueryHandle          = Handle<HwTimerQuery>;
-using VertexBufferHandle        = Handle<HwVertexBuffer>;
-using VertexBufferInfoHandle    = Handle<HwVertexBufferInfo>;
-using DescriptorSetLayoutHandle = Handle<HwDescriptorSetLayout>;
-using DescriptorSetHandle       = Handle<HwDescriptorSet>;
+using BufferObjectHandle     = Handle<HwBufferObject>;
+using FenceHandle            = Handle<HwFence>;
+using IndexBufferHandle      = Handle<HwIndexBuffer>;
+using ProgramHandle          = Handle<HwProgram>;
+using RenderPrimitiveHandle  = Handle<HwRenderPrimitive>;
+using RenderTargetHandle     = Handle<HwRenderTarget>;
+using SamplerGroupHandle     = Handle<HwSamplerGroup>;
+using StreamHandle           = Handle<HwStream>;
+using SwapChainHandle        = Handle<HwSwapChain>;
+using TextureHandle          = Handle<HwTexture>;
+using TimerQueryHandle       = Handle<HwTimerQuery>;
+using VertexBufferHandle     = Handle<HwVertexBuffer>;
+using VertexBufferInfoHandle = Handle<HwVertexBufferInfo>;
 
 } // namespace filament::backend
 

filament/backend/include/backend/PipelineState.h

@@ -22,23 +22,15 @@
 
 #include <utils/ostream.h>
 
-#include <array>
-
 #include <stdint.h>
 
 namespace filament::backend {
 
 //! \privatesection
 
-struct PipelineLayout {
-    using SetLayout = std::array<Handle<HwDescriptorSetLayout>, MAX_DESCRIPTOR_SET_COUNT>;
-    SetLayout setLayout;      // 16
-};
-
 struct PipelineState {
     Handle<HwProgram> program;                                              //  4
     Handle<HwVertexBufferInfo> vertexBufferInfo;                            //  4
-    PipelineLayout pipelineLayout;                                          // 16
     RasterState rasterState;                                                //  4
     StencilState stencilState;                                              // 12
     PolygonOffset polygonOffset;                                            //  8

filament/backend/include/backend/Platform.h

@@ -41,26 +41,6 @@ public:
     struct Fence {};
     struct Stream {};
 
-    /**
-     * The type of technique for stereoscopic rendering. (Note that the materials used will need to
-     * be compatible with the chosen technique.)
-     */
-    enum class StereoscopicType : uint8_t {
-        /**
-         * No stereoscopic rendering
-         */
-        NONE,
-        /**
-         * Stereoscopic rendering is performed using instanced rendering technique.
-         */
-        INSTANCED,
-        /**
-         * Stereoscopic rendering is performed using the multiview feature from the graphics
-         * backend.
-         */
-        MULTIVIEW,
-    };
-
     struct DriverConfig {
         /**
          * Size of handle arena in bytes. Setting to 0 indicates default value is to be used.
@@ -68,7 +48,12 @@ public:
          */
         size_t handleArenaSize = 0;
 
-        size_t metalUploadBufferSizeBytes = 512 * 1024;
+        /**
+         * This number of most-recently destroyed textures will be tracked for use-after-free.
+         * Throws an exception when a texture is freed but still bound to a SamplerGroup and used in
+         * a draw call. 0 disables completely. Currently only respected by the Metal backend.
+         */
+        size_t textureUseAfterFreePoolSize = 0;
 
         /**
          * Set to `true` to forcibly disable parallel shader compilation in the backend.
@@ -80,24 +65,6 @@ public:
          * Disable backend handles use-after-free checks.
          */
         bool disableHandleUseAfterFreeCheck = false;
-
-        /**
-         * Force GLES2 context if supported, or pretend the context is ES2. Only meaningful on
-         * GLES 3.x backends.
-         */
-        bool forceGLES2Context = false;
-
-        /**
-         * Sets the technique for stereoscopic rendering.
-         */
-        StereoscopicType stereoscopicType = StereoscopicType::NONE;
-
-        /**
-         * Assert the native window associated to a SwapChain is valid when calling makeCurrent().
-         * This is only supported for:
-         *      - PlatformEGLAndroid
-         */
-        bool assertNativeWindowIsValid = false;
     };
 
     Platform() noexcept;

filament/backend/include/backend/PresentCallable.h

@@ -48,7 +48,7 @@ namespace filament::backend {
  * and optional user data:
  *
  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
- * swapChain->setFrameScheduledCallback(nullptr, myFrameScheduledCallback);
+ * swapChain->setFrameScheduledCallback(myFrameScheduledCallback, nullptr);
  * if (renderer->beginFrame(swapChain)) {
  *     renderer->render(view);
  *     renderer->endFrame();
@@ -58,6 +58,8 @@ namespace filament::backend {
  * @remark Only Filament's Metal backend supports PresentCallables and frame callbacks. Other
  * backends ignore the callback (which will never be called) and proceed normally.
  *
+ * @remark The SwapChain::FrameScheduledCallback is called on an arbitrary thread.
+ *
  * Applications *must* call each PresentCallable they receive. Each PresentCallable represents a
  * frame that is waiting to be presented. If an application fails to call a PresentCallable, a
  * memory leak could occur. To "cancel" the presentation of a frame, pass false to the

filament/backend/include/backend/Program.h

@@ -24,11 +24,9 @@
 
 #include <backend/DriverEnums.h>
 
-#include <array>
-#include <unordered_map>
-#include <tuple>
-#include <utility>
-#include <variant>
+#include <array>    // FIXME: STL headers are not allowed in public headers
+#include <utility>  // FIXME: STL headers are not allowed in public headers
+#include <variant>  // FIXME: STL headers are not allowed in public headers
 
 #include <stddef.h>
 #include <stdint.h>
@@ -42,36 +40,29 @@ public:
     static constexpr size_t UNIFORM_BINDING_COUNT = CONFIG_UNIFORM_BINDING_COUNT;
     static constexpr size_t SAMPLER_BINDING_COUNT = CONFIG_SAMPLER_BINDING_COUNT;
 
-    struct Descriptor {
-        utils::CString name;
-        backend::DescriptorType type;
-        backend::descriptor_binding_t binding;
+    struct Sampler {
+        utils::CString name = {};   // name of the sampler in the shader
+        uint32_t binding = 0;       // binding point of the sampler in the shader
     };
 
-    struct SpecializationConstant {
-        using Type = std::variant<int32_t, float, bool>;
-        uint32_t id;    // id set in glsl
-        Type value;     // value and type
+    struct SamplerGroupData {
+        utils::FixedCapacityVector<Sampler> samplers;
+        ShaderStageFlags stageFlags = ShaderStageFlags::ALL_SHADER_STAGE_FLAGS;
     };
 
-    struct Uniform { // For ES2 support
+    struct Uniform {
         utils::CString name;    // full qualified name of the uniform field
         uint16_t offset;        // offset in 'uint32_t' into the uniform buffer
         uint8_t size;           // >1 for arrays
         UniformType type;       // uniform type
     };
 
-    using DescriptorBindingsInfo = utils::FixedCapacityVector<Descriptor>;
-    using DescriptorSetInfo = std::array<DescriptorBindingsInfo, MAX_DESCRIPTOR_SET_COUNT>;
-    using SpecializationConstantsInfo = utils::FixedCapacityVector<SpecializationConstant>;
+    using UniformBlockInfo = std::array<utils::CString, UNIFORM_BINDING_COUNT>;
+    using UniformInfo = utils::FixedCapacityVector<Uniform>;
+    using SamplerGroupInfo = std::array<SamplerGroupData, SAMPLER_BINDING_COUNT>;
     using ShaderBlob = utils::FixedCapacityVector<uint8_t>;
     using ShaderSource = std::array<ShaderBlob, SHADER_TYPE_COUNT>;
 
-    using AttributesInfo = utils::FixedCapacityVector<std::pair<utils::CString, uint8_t>>;
-    using UniformInfo = utils::FixedCapacityVector<Uniform>;
-    using BindingUniformsInfo = utils::FixedCapacityVector<
-            std::tuple<uint8_t, utils::CString, Program::UniformInfo>>;
-
     Program() noexcept;
 
     Program(const Program& rhs) = delete;
@@ -88,103 +79,85 @@ public:
     Program& diagnostics(utils::CString const& name,
             utils::Invocable<utils::io::ostream&(utils::io::ostream& out)>&& logger);
 
-    // Sets one of the program's shader (e.g. vertex, fragment)
+    // sets one of the program's shader (e.g. vertex, fragment)
     // string-based shaders are null terminated, consequently the size parameter must include the
     // null terminating character.
     Program& shader(ShaderStage shader, void const* data, size_t size);
 
-    // Sets the language of the shader sources provided with shader() (defaults to ESSL3)
-    Program& shaderLanguage(ShaderLanguage shaderLanguage);
+    // Note: This is only needed for GLES3.0 backends, because the layout(binding=) syntax is
+    //       not permitted in glsl. The backend needs a way to associate a uniform block
+    //       to a binding point.
+    Program& uniformBlockBindings(
+            utils::FixedCapacityVector<std::pair<utils::CString, uint8_t>> const& uniformBlockBindings) noexcept;
 
-    // Descriptor binding (set, binding, type -> shader name) info
-    Program& descriptorBindings(backend::descriptor_set_t set,
-            DescriptorBindingsInfo descriptorBindings) noexcept;
+    // Note: This is only needed for GLES2.0, this is used to emulate UBO. This function tells
+    // the program everything it needs to know about the uniforms at a given binding
+    Program& uniforms(uint32_t index, UniformInfo const& uniforms) noexcept;
 
-    Program& specializationConstants(SpecializationConstantsInfo specConstants) noexcept;
+    // Note: This is only needed for GLES2.0.
+    Program& attributes(
+            utils::FixedCapacityVector<std::pair<utils::CString, uint8_t>> attributes) noexcept;
 
-    struct PushConstant {
-        utils::CString name;
-        ConstantType type;
+    // sets the 'bindingPoint' sampler group descriptor for this program.
+    // 'samplers' can be destroyed after this call.
+    // This effectively associates a set of (BindingPoints, index) to a texture unit in the shader.
+    // Or more precisely, what layout(binding=) is set to in GLSL.
+    Program& setSamplerGroup(size_t bindingPoint, ShaderStageFlags stageFlags,
+            Sampler const* samplers, size_t count) noexcept;
+
+    struct SpecializationConstant {
+        using Type = std::variant<int32_t, float, bool>;
+        uint32_t id;                                // id set in glsl
+        Type value;                                 // value and type
     };
 
-    Program& pushConstants(ShaderStage stage,
-            utils::FixedCapacityVector<PushConstant> constants) noexcept;
+    Program& specializationConstants(
+            utils::FixedCapacityVector<SpecializationConstant> specConstants) noexcept;
 
     Program& cacheId(uint64_t cacheId) noexcept;
 
-    Program& multiview(bool multiview) noexcept;
-
-    // For ES2 support only...
-    Program& uniforms(uint32_t index, utils::CString name, UniformInfo uniforms) noexcept;
-    Program& attributes(AttributesInfo attributes) noexcept;
-
-    //
-    // Getters for program construction...
-    //
-
     ShaderSource const& getShadersSource() const noexcept { return mShadersSource; }
     ShaderSource& getShadersSource() noexcept { return mShadersSource; }
 
-    utils::CString const& getName() const noexcept { return mName; }
-    utils::CString& getName() noexcept { return mName; }
+    UniformBlockInfo const& getUniformBlockBindings() const noexcept { return mUniformBlocks; }
+    UniformBlockInfo& getUniformBlockBindings() noexcept { return mUniformBlocks; }
 
-    auto const& getShaderLanguage() const { return mShaderLanguage; }
+    SamplerGroupInfo const& getSamplerGroupInfo() const { return mSamplerGroups; }
+    SamplerGroupInfo& getSamplerGroupInfo() { return mSamplerGroups; }
 
-    uint64_t getCacheId() const noexcept { return mCacheId; }
-
-    bool isMultiview() const noexcept { return mMultiview; }
-
-    CompilerPriorityQueue getPriorityQueue() const noexcept { return mPriorityQueue; }
-
-    SpecializationConstantsInfo const& getSpecializationConstants() const noexcept {
-        return mSpecializationConstants;
-    }
-
-    SpecializationConstantsInfo& getSpecializationConstants() noexcept {
-        return mSpecializationConstants;
-    }
-
-    DescriptorSetInfo& getDescriptorBindings() noexcept {
-        return mDescriptorBindings;
-    }
-
-    utils::FixedCapacityVector<PushConstant> const& getPushConstants(
-            ShaderStage stage) const noexcept {
-        return mPushConstants[static_cast<uint8_t>(stage)];
-    }
-
-    utils::FixedCapacityVector<PushConstant>& getPushConstants(ShaderStage stage) noexcept {
-        return mPushConstants[static_cast<uint8_t>(stage)];
-    }
-
-    auto const& getBindingUniformInfo() const { return mBindingUniformsInfo; }
-    auto& getBindingUniformInfo() { return mBindingUniformsInfo; }
+    auto const& getBindingUniformInfo() const { return mBindingUniformInfo; }
+    auto& getBindingUniformInfo() { return mBindingUniformInfo; }
 
     auto const& getAttributes() const { return mAttributes; }
     auto& getAttributes() { return mAttributes; }
 
+    utils::CString const& getName() const noexcept { return mName; }
+    utils::CString& getName() noexcept { return mName; }
+
+    utils::FixedCapacityVector<SpecializationConstant> const& getSpecializationConstants() const noexcept {
+        return mSpecializationConstants;
+    }
+    utils::FixedCapacityVector<SpecializationConstant>& getSpecializationConstants() noexcept {
+        return mSpecializationConstants;
+    }
+
+    uint64_t getCacheId() const noexcept { return mCacheId; }
+
+    CompilerPriorityQueue getPriorityQueue() const noexcept { return mPriorityQueue; }
+
 private:
     friend utils::io::ostream& operator<<(utils::io::ostream& out, const Program& builder);
 
+    UniformBlockInfo mUniformBlocks = {};
+    SamplerGroupInfo mSamplerGroups = {};
     ShaderSource mShadersSource;
-    ShaderLanguage mShaderLanguage = ShaderLanguage::ESSL3;
     utils::CString mName;
     uint64_t mCacheId{};
-    CompilerPriorityQueue mPriorityQueue = CompilerPriorityQueue::HIGH;
     utils::Invocable<utils::io::ostream&(utils::io::ostream& out)> mLogger;
-    SpecializationConstantsInfo mSpecializationConstants;
-    std::array<utils::FixedCapacityVector<PushConstant>, SHADER_TYPE_COUNT> mPushConstants;
-    DescriptorSetInfo mDescriptorBindings;
-
-    // For ES2 support only
-    AttributesInfo mAttributes;
-    BindingUniformsInfo mBindingUniformsInfo;
-
-    // Indicates the current engine was initialized with multiview stereo, and the variant for this
-    // program contains STE flag. This will be referred later for the OpenGL shader compiler to
-    // determine whether shader code replacement for the num_views should be performed.
-    // This variable could be promoted as a more generic variable later if other similar needs occur.
-    bool mMultiview = false;
+    utils::FixedCapacityVector<SpecializationConstant> mSpecializationConstants;
+    utils::FixedCapacityVector<std::pair<utils::CString, uint8_t>> mAttributes;
+    std::array<UniformInfo, Program::UNIFORM_BINDING_COUNT> mBindingUniformInfo;
+    CompilerPriorityQueue mPriorityQueue = CompilerPriorityQueue::HIGH;
 };
 
 } // namespace filament::backend

filament/backend/include/backend/TargetBufferInfo.h

@@ -29,33 +29,17 @@ namespace filament::backend {
 //! \privatesection
 
 struct TargetBufferInfo {
-    // note: the parameters of this constructor are not in the order of this structure's fields
-    TargetBufferInfo(Handle<HwTexture> handle, uint8_t level, uint16_t layer) noexcept
-            : handle(handle), level(level), layer(layer) {
-    }
-
-    TargetBufferInfo(Handle<HwTexture> handle, uint8_t level) noexcept
-            : handle(handle), level(level) {
-    }
-
-    TargetBufferInfo(Handle<HwTexture> handle) noexcept // NOLINT(*-explicit-constructor)
-            : handle(handle) {
-    }
-
-    TargetBufferInfo() noexcept = default;
-
     // texture to be used as render target
     Handle<HwTexture> handle;
 
+    // starting layer index for multiview. This value is only used when the `layerCount` for the
+    // render target is greater than 1.
+    uint8_t baseViewIndex = 0;
+
     // level to be used
     uint8_t level = 0;
 
-    // - For cubemap textures, this indicates the face of the cubemap. See TextureCubemapFace for
-    //   the face->layer mapping)
-    // - For 2d array, cubemap array, and 3d textures, this indicates an index of a single layer of
-    //   them.
-    // - For multiview textures (i.e., layerCount for the RenderTarget is greater than 1), this
-    //   indicates a starting layer index of the current 2d array texture for multiview.
+    // for cubemaps and 3D textures. See TextureCubemapFace for the face->layer mapping
     uint16_t layer = 0;
 };
 
@@ -80,7 +64,7 @@ public:
 
     MRT() noexcept = default;
 
-    MRT(TargetBufferInfo const& color) noexcept // NOLINT(hicpp-explicit-conversions, *-explicit-constructor)
+    MRT(TargetBufferInfo const& color) noexcept // NOLINT(hicpp-explicit-conversions)
             : mInfos{ color } {
     }
 
@@ -100,7 +84,7 @@ public:
 
     // this is here for backward compatibility
     MRT(Handle<HwTexture> handle, uint8_t level, uint16_t layer) noexcept
-            : mInfos{{ handle, level, layer }} {
+            : mInfos{{ handle, 0, level, layer }} {
     }
 };
 

filament/backend/include/backend/platforms/OpenGLPlatform.h

@@ -140,23 +140,6 @@ public:
      */
     virtual uint32_t getDefaultFramebufferObject() noexcept;
 
-    /**
-     * Called by the backend when a frame starts.
-     * @param steady_clock_ns vsync time point on the monotonic clock
-     * @param refreshIntervalNs refresh interval in nanosecond
-     * @param frameId a frame id
-     */
-    virtual void beginFrame(
-            int64_t monotonic_clock_ns,
-            int64_t refreshIntervalNs,
-            uint32_t frameId) noexcept;
-
-    /**
-     * Called by the backend when a frame ends.
-     * @param frameId the frame id used in beginFrame
-     */
-    virtual void endFrame(
-            uint32_t frameId) noexcept;
 
     /**
      * Type of contexts available
@@ -208,12 +191,6 @@ public:
             utils::Invocable<void()> preContextChange,
             utils::Invocable<void(size_t index)> postContextChange) noexcept;
 
-    /**
-     * Called by the backend just before calling commit()
-     * @see commit()
-     */
-    virtual void preCommit() noexcept;
-
     /**
      * Called by the driver once the current frame finishes drawing. Typically, this should present
      * the drawSwapChain. This is for example where `eglMakeCurrent()` would be called.

filament/backend/include/backend/platforms/PlatformEGLAndroid.h

@@ -22,10 +22,6 @@
 #include <backend/platforms/OpenGLPlatform.h>
 #include <backend/platforms/PlatformEGL.h>
 
-#include <utils/android/PerformanceHintManager.h>
-
-#include <chrono>
-
 #include <stddef.h>
 #include <stdint.h>
 
@@ -62,13 +58,6 @@ protected:
 
     void terminate() noexcept override;
 
-    void beginFrame(
-            int64_t monotonic_clock_ns,
-            int64_t refreshIntervalNs,
-            uint32_t frameId) noexcept override;
-
-    void preCommit() noexcept override;
-
     /**
      * Set the presentation time using `eglPresentationTimeANDROID`
      * @param presentationTimeInNanosecond
@@ -89,28 +78,9 @@ protected:
      */
     AcquiredImage transformAcquiredImage(AcquiredImage source) noexcept override;
 
-protected:
-    bool makeCurrent(ContextType type,
-            SwapChain* drawSwapChain,
-            SwapChain* readSwapChain) noexcept override;
-
 private:
-    struct InitializeJvmForPerformanceManagerIfNeeded {
-        InitializeJvmForPerformanceManagerIfNeeded();
-    };
-
     int mOSVersion;
     ExternalStreamManagerAndroid& mExternalStreamManager;
-    InitializeJvmForPerformanceManagerIfNeeded const mInitializeJvmForPerformanceManagerIfNeeded;
-    utils::PerformanceHintManager mPerformanceHintManager;
-    utils::PerformanceHintManager::Session mPerformanceHintSession;
-
-    using clock = std::chrono::high_resolution_clock;
-    clock::time_point mStartTimeOfActualWork;
-
-    void* mNativeWindowLib = nullptr;
-    int32_t (*ANativeWindow_getBuffersDefaultDataSpace)(ANativeWindow* window) = nullptr;
-    bool mAssertNativeWindowIsValid = false;
 };
 
 } // namespace filament::backend

filament/backend/include/backend/platforms/PlatformOSMesa.h

@@ -1,64 +0,0 @@
-/*
- * Copyright (C) 2024 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_OPENGL_OPENGL_PLATFORM_OSMESA_H
-#define TNT_FILAMENT_BACKEND_OPENGL_OPENGL_PLATFORM_OSMESA_H
-
-#include <stdint.h>
-
-#include "bluegl/BlueGL.h"
-
-#include <osmesa.h>
-
-#include <backend/platforms/OpenGLPlatform.h>
-#include <backend/DriverEnums.h>
-
-namespace filament::backend {
-
-/**
- * A concrete implementation of OpenGLPlatform that uses OSMesa, which is an offscreen
- * context that can be used in conjunction with Mesa for software rasterization.
- * See https://docs.mesa3d.org/osmesa.html for more information.
- */
-class PlatformOSMesa : public OpenGLPlatform {
-protected:
-    // --------------------------------------------------------------------------------------------
-    // Platform Interface
-
-    Driver* createDriver(void* sharedGLContext, const DriverConfig& driverConfig) noexcept override;
-
-    int getOSVersion() const noexcept final override { return 0; }
-
-    // --------------------------------------------------------------------------------------------
-    // OpenGLPlatform Interface
-
-    void terminate() noexcept override;
-
-    SwapChain* createSwapChain(void* nativewindow, uint64_t flags) noexcept override;
-    SwapChain* createSwapChain(uint32_t width, uint32_t height, uint64_t flags) noexcept override;
-    void destroySwapChain(SwapChain* swapChain) noexcept override;
-    bool makeCurrent(ContextType type, SwapChain* drawSwapChain,
-            SwapChain* readSwapChain) noexcept override;
-    void commit(SwapChain* swapChain) noexcept override;
-
-private:
-    OSMesaContext mContext;
-    void* mOsMesaApi = nullptr;
-};
-
-} // namespace filament::backend
-
-#endif // TNT_FILAMENT_BACKEND_OPENGL_OPENGL_PLATFORM_OSMESA_H

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

@@ -23,9 +23,9 @@
 
 #include <utils/CString.h>
 #include <utils/FixedCapacityVector.h>
-#include <utils/Hash.h>
 #include <utils/PrivateImplementation.h>
 
+#include <string_view>
 #include <tuple>
 #include <unordered_set>
 
@@ -47,14 +47,6 @@ struct VulkanPlatformPrivate;
 class VulkanPlatform : public Platform, utils::PrivateImplementation<VulkanPlatformPrivate> {
 public:
 
-    struct ExtensionHashFn {
-        std::size_t operator()(utils::CString const& s) const noexcept {
-            return std::hash<std::string>{}(s.data());
-        }
-    };
-    // Utility for managing device or instance extensions during initialization.
-    using ExtensionSet = std::unordered_set<utils::CString, ExtensionHashFn>;
-
     /**
      * A collection of handles to objects and metadata that comprises a Vulkan context. The client
      * can instantiate this struct and pass to Engine::Builder::sharedContext if they wishes to
@@ -88,21 +80,6 @@ public:
         VkFormat colorFormat = VK_FORMAT_UNDEFINED;
         VkFormat depthFormat = VK_FORMAT_UNDEFINED;
         VkExtent2D extent = {0, 0};
-        bool isProtected = false;
-    };
-
-    struct ImageSyncData {
-        static constexpr uint32_t INVALID_IMAGE_INDEX = UINT32_MAX;
-
-        // The index of the next image as returned by vkAcquireNextImage or equivalent.
-        uint32_t imageIndex = INVALID_IMAGE_INDEX;
-
-        // 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();
@@ -142,12 +119,6 @@ public:
          * before recreating the swapchain. Default is true.
          */
         bool flushAndWaitOnWindowResize = true;
-
-        /**
-         * Whether the swapchain image should be transitioned to a layout suitable for
-         * presentation. Default is true.
-         */
-        bool transitionSwapChainImageLayoutForPresent = true;
     };
 
     /**
@@ -176,10 +147,13 @@ public:
      * corresponding VkImage will be used as the output color attachment. The client should signal
      * the `clientSignal` semaphore when the image is ready to be used by the backend.
      * @param handle         The handle returned by createSwapChain()
-     * @param outImageSyncData The synchronization data used for image readiness
+     * @param clientSignal   The semaphore that the client will signal to indicate that the backend
+     *                       may render into the image.
+     * @param index          Pointer to memory that will be filled with the index that corresponding
+     *                       to an image in the `SwapChainBundle.colors` array.
      * @return               Result of acquire
      */
-    virtual VkResult acquire(SwapChainPtr handle, ImageSyncData* outImageSyncData);
+    virtual VkResult acquire(SwapChainPtr handle, VkSemaphore clientSignal, uint32_t* index);
 
     /**
      * Present the image corresponding to `index` to the display. The client should wait on
@@ -200,13 +174,6 @@ public:
      */
     virtual bool hasResized(SwapChainPtr handle);
 
-    /**
-     * Check if the surface is protected.
-     * @param handle             The handle returned by createSwapChain()
-     * @return                   Whether the swapchain is protected
-     */
-    virtual bool isProtected(SwapChainPtr handle);
-
     /**
      * Carry out a recreation of the swapchain.
      * @param handle             The handle returned by createSwapChain()
@@ -225,13 +192,6 @@ public:
     virtual SwapChainPtr createSwapChain(void* nativeWindow, uint64_t flags = 0,
             VkExtent2D extent = {0, 0});
 
-    /**
-     * Allows implementers to provide instance extensions that they'd like to include in the
-     * instance creation.
-     * @return          A set of extensions to enable for the instance.
-     */
-    virtual ExtensionSet getRequiredInstanceExtensions() { return {}; }
-
     /**
      * Destroy the swapchain.
      * @param handle    The handle returned by createSwapChain()
@@ -275,27 +235,11 @@ public:
      */
     VkQueue getGraphicsQueue() const noexcept;
 
-    /**
-    * @return The family index of the protected graphics queue selected for the
-    *          Vulkan backend.
-    */
-    uint32_t getProtectedGraphicsQueueFamilyIndex() const noexcept;
-
-    /**
-     * @return The index of the protected graphics queue (if there are multiple
-     *          graphics queues) selected for the Vulkan backend.
-     */
-    uint32_t getProtectedGraphicsQueueIndex() const noexcept;
-
-    /**
-     * @return The protected queue that was selected for the Vulkan backend.
-     */
-    VkQueue getProtectedGraphicsQueue() const noexcept;
-
 private:
-    static ExtensionSet getSwapchainInstanceExtensions();
-
     // Platform dependent helper methods
+    using ExtensionSet = std::unordered_set<std::string_view>;
+    static ExtensionSet getRequiredInstanceExtensions();
+
     using SurfaceBundle = std::tuple<VkSurfaceKHR, VkExtent2D>;
     static SurfaceBundle createVkSurfaceKHR(void* nativeWindow, VkInstance instance,
             uint64_t flags) noexcept;

filament/backend/include/private/backend/CommandBufferQueue.h

@@ -82,7 +82,6 @@ public:
     void requestExit();
 
     // suspend or unsuspend the queue.
-    bool isPaused() const noexcept;
     void setPaused(bool paused);
 
     bool isExitRequested() const;

filament/backend/include/private/backend/CommandStream.h

@@ -134,7 +134,7 @@ struct CommandType<void (Driver::*)(ARGS...)> {
 
     public:
         template<typename M, typename D>
-        static inline void execute(M&& method, D&& driver, CommandBase* base, intptr_t* next) {
+        static inline void execute(M&& method, D&& driver, CommandBase* base, intptr_t* next) noexcept {
             Command* self = static_cast<Command*>(base);
             *next = align(sizeof(Command));
 #if DEBUG_COMMAND_STREAM
@@ -168,7 +168,7 @@ struct CommandType<void (Driver::*)(ARGS...)> {
 
 class CustomCommand : public CommandBase {
     std::function<void()> mCommand;
-    static void execute(Driver&, CommandBase* base, intptr_t* next);
+    static void execute(Driver&, CommandBase* base, intptr_t* next) noexcept;
 public:
     inline CustomCommand(CustomCommand&& rhs) = default;
     inline explicit CustomCommand(std::function<void()> cmd)

filament/backend/include/private/backend/Driver.h

@@ -18,7 +18,6 @@
 #define TNT_FILAMENT_BACKEND_PRIVATE_DRIVER_H
 
 #include <backend/CallbackHandler.h>
-#include <backend/DescriptorSetOffsetArray.h>
 #include <backend/DriverApiForward.h>
 #include <backend/DriverEnums.h>
 #include <backend/Handle.h>
@@ -77,7 +76,7 @@ public:
     // the fn function will execute a batch of driver commands
     // this gives the driver a chance to wrap their execution in a meaningful manner
     // the default implementation simply calls fn
-    virtual void execute(std::function<void(void)> const& fn);
+    virtual void execute(std::function<void(void)> const& fn) noexcept;
 
     // This is called on debug build, or when enabled manually on the backend thread side.
     virtual void debugCommandBegin(CommandStream* cmds,

filament/backend/include/private/backend/DriverAPI.inc

@@ -133,19 +133,18 @@ DECL_DRIVER_API_0(tick)
 
 DECL_DRIVER_API_N(beginFrame,
         int64_t, monotonic_clock_ns,
-        int64_t, refreshIntervalNs,
         uint32_t, frameId)
 
 DECL_DRIVER_API_N(setFrameScheduledCallback,
         backend::SwapChainHandle, sch,
-        backend::CallbackHandler*, handler,
-        backend::FrameScheduledCallback&&, callback,
-        uint64_t, flags)
+        backend::FrameScheduledCallback, callback,
+        void*, user)
 
 DECL_DRIVER_API_N(setFrameCompletedCallback,
         backend::SwapChainHandle, sch,
         backend::CallbackHandler*, handler,
-        utils::Invocable<void(void)>&&, callback)
+        backend::CallbackHandler::Callback, callback,
+        void*, user)
 
 DECL_DRIVER_API_N(setPresentationTime,
         int64_t, monotonic_clock_ns)
@@ -163,10 +162,6 @@ DECL_DRIVER_API_0(finish)
 // reset state tracking, if the driver does any state tracking (e.g. GL)
 DECL_DRIVER_API_0(resetState)
 
-DECL_DRIVER_API_N(setDebugTag,
-        backend::HandleBase::HandleId, handleId,
-        utils::CString, tag)
-
 /*
  * Creating driver objects
  * -----------------------
@@ -201,33 +196,20 @@ DECL_DRIVER_API_R_N(backend::TextureHandle, createTexture,
         uint32_t, depth,
         backend::TextureUsage, usage)
 
-DECL_DRIVER_API_R_N(backend::TextureHandle, createTextureView,
-        backend::TextureHandle, texture,
-        uint8_t, baseLevel,
-        uint8_t, levelCount)
-
-DECL_DRIVER_API_R_N(backend::TextureHandle, createTextureViewSwizzle,
-        backend::TextureHandle, texture,
+DECL_DRIVER_API_R_N(backend::TextureHandle, createTextureSwizzled,
+        backend::SamplerType, target,
+        uint8_t, levels,
+        backend::TextureFormat, format,
+        uint8_t, samples,
+        uint32_t, width,
+        uint32_t, height,
+        uint32_t, depth,
+        backend::TextureUsage, usage,
         backend::TextureSwizzle, r,
         backend::TextureSwizzle, g,
         backend::TextureSwizzle, b,
         backend::TextureSwizzle, a)
 
-DECL_DRIVER_API_R_N(backend::TextureHandle, createTextureExternalImage,
-        backend::TextureFormat, format,
-        uint32_t, width,
-        uint32_t, height,
-        backend::TextureUsage, usage,
-        void*, image)
-
-DECL_DRIVER_API_R_N(backend::TextureHandle, createTextureExternalImagePlane,
-        backend::TextureFormat, format,
-        uint32_t, width,
-        uint32_t, height,
-        backend::TextureUsage, usage,
-        void*, image,
-        uint32_t, plane)
-
 DECL_DRIVER_API_R_N(backend::TextureHandle, importTexture,
         intptr_t, id,
         backend::SamplerType, target,
@@ -239,6 +221,9 @@ DECL_DRIVER_API_R_N(backend::TextureHandle, importTexture,
         uint32_t, depth,
         backend::TextureUsage, usage)
 
+DECL_DRIVER_API_R_N(backend::SamplerGroupHandle, createSamplerGroup,
+        uint32_t, size, utils::FixedSizeString<32>, debugName)
+
 DECL_DRIVER_API_R_N(backend::RenderPrimitiveHandle, createRenderPrimitive,
         backend::VertexBufferHandle, vbh,
         backend::IndexBufferHandle, ibh,
@@ -272,53 +257,25 @@ DECL_DRIVER_API_R_N(backend::SwapChainHandle, createSwapChainHeadless,
 
 DECL_DRIVER_API_R_0(backend::TimerQueryHandle, createTimerQuery)
 
-DECL_DRIVER_API_R_N(backend::DescriptorSetLayoutHandle, createDescriptorSetLayout,
-        backend::DescriptorSetLayout&&, info)
-
-DECL_DRIVER_API_R_N(backend::DescriptorSetHandle, createDescriptorSet,
-        backend::DescriptorSetLayoutHandle, dslh)
-
-DECL_DRIVER_API_N(updateDescriptorSetBuffer,
-        backend::DescriptorSetHandle, dsh,
-        backend::descriptor_binding_t, binding,
-        backend::BufferObjectHandle, boh,
-        uint32_t, offset,
-        uint32_t, size
-)
-
-DECL_DRIVER_API_N(updateDescriptorSetTexture,
-        backend::DescriptorSetHandle, dsh,
-        backend::descriptor_binding_t, binding,
-        backend::TextureHandle, th,
-        SamplerParams, params
-)
-
-DECL_DRIVER_API_N(bindDescriptorSet,
-        backend::DescriptorSetHandle, dsh,
-        backend::descriptor_set_t, set,
-        backend::DescriptorSetOffsetArray&&, offsets
-)
-
 
 /*
  * Destroying driver objects
  * -------------------------
  */
 
-DECL_DRIVER_API_N(destroyVertexBuffer,          backend::VertexBufferHandle, vbh)
-DECL_DRIVER_API_N(destroyVertexBufferInfo,      backend::VertexBufferInfoHandle, vbih)
-DECL_DRIVER_API_N(destroyIndexBuffer,           backend::IndexBufferHandle, ibh)
-DECL_DRIVER_API_N(destroyBufferObject,          backend::BufferObjectHandle, ibh)
-DECL_DRIVER_API_N(destroyRenderPrimitive,       backend::RenderPrimitiveHandle, rph)
-DECL_DRIVER_API_N(destroyProgram,               backend::ProgramHandle, ph)
-DECL_DRIVER_API_N(destroyTexture,               backend::TextureHandle, th)
-DECL_DRIVER_API_N(destroyRenderTarget,          backend::RenderTargetHandle, rth)
-DECL_DRIVER_API_N(destroySwapChain,             backend::SwapChainHandle, sch)
-DECL_DRIVER_API_N(destroyStream,                backend::StreamHandle, sh)
-DECL_DRIVER_API_N(destroyTimerQuery,            backend::TimerQueryHandle, sh)
-DECL_DRIVER_API_N(destroyFence,                 backend::FenceHandle, fh)
-DECL_DRIVER_API_N(destroyDescriptorSetLayout,   backend::DescriptorSetLayoutHandle, dslh)
-DECL_DRIVER_API_N(destroyDescriptorSet,         backend::DescriptorSetHandle, dsh)
+DECL_DRIVER_API_N(destroyVertexBuffer,    backend::VertexBufferHandle, vbh)
+DECL_DRIVER_API_N(destroyVertexBufferInfo,backend::VertexBufferInfoHandle, vbih)
+DECL_DRIVER_API_N(destroyIndexBuffer,     backend::IndexBufferHandle, ibh)
+DECL_DRIVER_API_N(destroyBufferObject,    backend::BufferObjectHandle, ibh)
+DECL_DRIVER_API_N(destroyRenderPrimitive, backend::RenderPrimitiveHandle, rph)
+DECL_DRIVER_API_N(destroyProgram,         backend::ProgramHandle, ph)
+DECL_DRIVER_API_N(destroySamplerGroup,    backend::SamplerGroupHandle, sbh)
+DECL_DRIVER_API_N(destroyTexture,         backend::TextureHandle, th)
+DECL_DRIVER_API_N(destroyRenderTarget,    backend::RenderTargetHandle, rth)
+DECL_DRIVER_API_N(destroySwapChain,       backend::SwapChainHandle, sch)
+DECL_DRIVER_API_N(destroyStream,          backend::StreamHandle, sh)
+DECL_DRIVER_API_N(destroyTimerQuery,      backend::TimerQueryHandle, sh)
+DECL_DRIVER_API_N(destroyFence,           backend::FenceHandle, fh)
 
 /*
  * Synchronous APIs
@@ -343,12 +300,10 @@ DECL_DRIVER_API_SYNCHRONOUS_0(bool, isFrameTimeSupported)
 DECL_DRIVER_API_SYNCHRONOUS_0(bool, isAutoDepthResolveSupported)
 DECL_DRIVER_API_SYNCHRONOUS_0(bool, isSRGBSwapChainSupported)
 DECL_DRIVER_API_SYNCHRONOUS_0(bool, isProtectedContentSupported)
-DECL_DRIVER_API_SYNCHRONOUS_0(bool, isStereoSupported)
+DECL_DRIVER_API_SYNCHRONOUS_N(bool, isStereoSupported, backend::StereoscopicType, stereoscopicType)
 DECL_DRIVER_API_SYNCHRONOUS_0(bool, isParallelShaderCompileSupported)
 DECL_DRIVER_API_SYNCHRONOUS_0(bool, isDepthStencilResolveSupported)
-DECL_DRIVER_API_SYNCHRONOUS_N(bool, isDepthStencilBlitSupported, backend::TextureFormat, format)
 DECL_DRIVER_API_SYNCHRONOUS_0(bool, isProtectedTexturesSupported)
-DECL_DRIVER_API_SYNCHRONOUS_0(bool, isDepthClampSupported)
 DECL_DRIVER_API_SYNCHRONOUS_0(uint8_t, getMaxDrawBuffers)
 DECL_DRIVER_API_SYNCHRONOUS_0(size_t, getMaxUniformBufferSize)
 DECL_DRIVER_API_SYNCHRONOUS_0(math::float2, getClipSpaceParams)
@@ -385,6 +340,15 @@ DECL_DRIVER_API_N(updateBufferObjectUnsynchronized,
 DECL_DRIVER_API_N(resetBufferObject,
         backend::BufferObjectHandle, ibh)
 
+DECL_DRIVER_API_N(updateSamplerGroup,
+        backend::SamplerGroupHandle, ubh,
+        backend::BufferDescriptor&&, data)
+
+DECL_DRIVER_API_N(setMinMaxLevels,
+        backend::TextureHandle, th,
+        uint32_t, minLevel,
+        uint32_t, maxLevel)
+
 DECL_DRIVER_API_N(update3DImage,
         backend::TextureHandle, th,
         uint32_t, level,
@@ -399,12 +363,10 @@ DECL_DRIVER_API_N(update3DImage,
 DECL_DRIVER_API_N(generateMipmaps,
         backend::TextureHandle, th)
 
-// Deprecated
 DECL_DRIVER_API_N(setExternalImage,
         backend::TextureHandle, th,
         void*, image)
 
-// Deprecated
 DECL_DRIVER_API_N(setExternalImagePlane,
         backend::TextureHandle, th,
         void*, image,
@@ -451,16 +413,32 @@ DECL_DRIVER_API_N(commit,
  * -----------------------
  */
 
-DECL_DRIVER_API_N(setPushConstant,
-        backend::ShaderStage, stage,
-        uint8_t, index,
-        backend::PushConstantVariant, value)
+DECL_DRIVER_API_N(bindUniformBuffer,
+        uint32_t, index,
+        backend::BufferObjectHandle, ubh)
+
+DECL_DRIVER_API_N(bindBufferRange,
+        BufferObjectBinding, bindingType,
+        uint32_t, index,
+        backend::BufferObjectHandle, ubh,
+        uint32_t, offset,
+        uint32_t, size)
+
+DECL_DRIVER_API_N(unbindBuffer,
+        BufferObjectBinding, bindingType,
+        uint32_t, index)
+
+DECL_DRIVER_API_N(bindSamplers,
+        uint32_t, index,
+        backend::SamplerGroupHandle, sbh)
 
 DECL_DRIVER_API_N(insertEventMarker,
-        const char*, string)
+        const char*, string,
+        uint32_t, len = 0)
 
 DECL_DRIVER_API_N(pushGroupMarker,
-        const char*, string)
+        const char*, string,
+        uint32_t, len = 0)
 
 DECL_DRIVER_API_0(popGroupMarker)
 
@@ -517,7 +495,7 @@ DECL_DRIVER_API_N(blit,
         math::uint2, size)
 
 DECL_DRIVER_API_N(bindPipeline,
-        backend::PipelineState const&, state)
+        backend::PipelineState, state)
 
 DECL_DRIVER_API_N(bindRenderPrimitive,
         backend::RenderPrimitiveHandle, rph)

filament/backend/include/private/backend/DriverApi.h

@@ -18,17 +18,6 @@
 #define TNT_FILAMENT_BACKEND_PRIVATE_DRIVERAPI_H
 
 #include "backend/DriverApiForward.h"
-
 #include "private/backend/CommandStream.h"
 
-#include <stddef.h>
-
-namespace filament::backend {
-
-inline void* allocateFromCommandStream(DriverApi& driver, size_t size, size_t alignment) noexcept {
-    return driver.allocate(size, alignment);
-}
-
-} // namespace filament::backend
-
 #endif // TNT_FILAMENT_BACKEND_PRIVATE_DRIVERAPI_H

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

@@ -20,12 +20,11 @@
 #include <backend/Handle.h>
 
 #include <utils/Allocator.h>
-#include <utils/CString.h>
 #include <utils/Log.h>
-#include <utils/Panic.h>
 #include <utils/compiler.h>
 #include <utils/debug.h>
 #include <utils/ostream.h>
+#include <utils/Panic.h>
 
 #include <tsl/robin_map.h>
 
@@ -38,9 +37,9 @@
 #include <stddef.h>
 #include <stdint.h>
 
-#define HandleAllocatorGL  HandleAllocator<32,  96, 136>    // ~4520 / pool / MiB
+#define HandleAllocatorGL  HandleAllocator<32,  64, 136>    // ~4520 / pool / MiB
 #define HandleAllocatorVK  HandleAllocator<64, 160, 312>    // ~1820 / pool / MiB
-#define HandleAllocatorMTL HandleAllocator<32,  64, 552>    // ~1660 / pool / MiB
+#define HandleAllocatorMTL HandleAllocator<32,  48, 552>    // ~1660 / pool / MiB
 
 namespace filament::backend {
 
@@ -66,7 +65,7 @@ public:
      *
      */
     template<typename D, typename ... ARGS>
-    Handle<D> allocateAndConstruct(ARGS&& ... args) {
+    Handle<D> allocateAndConstruct(ARGS&& ... args) noexcept {
         Handle<D> h{ allocateHandle<D>() };
         D* addr = handle_cast<D*>(h);
         new(addr) D(std::forward<ARGS>(args)...);
@@ -98,7 +97,7 @@ public:
      */
     template<typename D, typename B, typename ... ARGS>
     typename std::enable_if_t<std::is_base_of_v<B, D>, D>*
-    destroyAndConstruct(Handle<B> const& handle, ARGS&& ... args) {
+    destroyAndConstruct(Handle<B> const& handle, ARGS&& ... args) noexcept {
         assert_invariant(handle);
         D* addr = handle_cast<D*>(const_cast<Handle<B>&>(handle));
         assert_invariant(addr);
@@ -164,89 +163,32 @@ public:
     inline typename std::enable_if_t<
             std::is_pointer_v<Dp> &&
             std::is_base_of_v<B, typename std::remove_pointer_t<Dp>>, Dp>
-    handle_cast(Handle<B>& handle) {
+    handle_cast(Handle<B>& handle) noexcept {
         assert_invariant(handle);
         auto [p, tag] = handleToPointer(handle.getId());
 
         if (isPoolHandle(handle.getId())) {
-            // check for pool handle use-after-free
+            // check for use after free
             if (UTILS_UNLIKELY(!mUseAfterFreeCheckDisabled)) {
                 uint8_t const age = (tag & HANDLE_AGE_MASK) >> HANDLE_AGE_SHIFT;
                 auto const pNode = static_cast<typename Allocator::Node*>(p);
                 uint8_t const expectedAge = pNode[-1].age;
-                // getHandleTag() is only called if the check fails.
-                FILAMENT_CHECK_POSTCONDITION(expectedAge == age)
-                        << "use-after-free of Handle with id=" << handle.getId()
-                        << ", tag=" << getHandleTag(handle.getId()).c_str_safe();
-            }
-        } else {
-            // check for heap handle use-after-free
-            if (UTILS_UNLIKELY(!mUseAfterFreeCheckDisabled)) {
-                uint8_t const index = (handle.getId() & HANDLE_INDEX_MASK);
-                // if we've already handed out this handle index before, it's definitely a
-                // use-after-free, otherwise it's probably just a corrupted handle
-                if (index < mId) {
-                    FILAMENT_CHECK_POSTCONDITION(p != nullptr)
-                            << "use-after-free of heap Handle with id=" << handle.getId()
-                            << ", tag=" << getHandleTag(handle.getId()).c_str_safe();
-                } else {
-                    FILAMENT_CHECK_POSTCONDITION(p != nullptr)
-                            << "corrupted heap Handle with id=" << handle.getId()
-                            << ", tag=" << getHandleTag(handle.getId()).c_str_safe();
-                }
+                ASSERT_POSTCONDITION(expectedAge == age,
+                        "use-after-free of Handle with id=%d", handle.getId());
             }
         }
 
         return static_cast<Dp>(p);
     }
 
-    template<typename B>
-    bool is_valid(Handle<B>& handle) {
-        if (!handle) {
-            // null handles are invalid
-            return false;
-        }
-        auto [p, tag] = handleToPointer(handle.getId());
-        if (isPoolHandle(handle.getId())) {
-            uint8_t const age = (tag & HANDLE_AGE_MASK) >> HANDLE_AGE_SHIFT;
-            auto const pNode = static_cast<typename Allocator::Node*>(p);
-            uint8_t const expectedAge = pNode[-1].age;
-            return expectedAge == age;
-        }
-        return p != nullptr;
-    }
-
     template<typename Dp, typename B>
     inline typename std::enable_if_t<
             std::is_pointer_v<Dp> &&
             std::is_base_of_v<B, typename std::remove_pointer_t<Dp>>, Dp>
-    handle_cast(Handle<B> const& handle) {
+    handle_cast(Handle<B> const& handle) noexcept {
         return handle_cast<Dp>(const_cast<Handle<B>&>(handle));
     }
 
-    void associateTagToHandle(HandleBase::HandleId id, utils::CString&& tag) noexcept {
-        // TODO: for now, only pool handles check for use-after-free, so we only keep tags for
-        // those
-        if (isPoolHandle(id)) {
-            // Truncate the age to get the debug tag
-            uint32_t const key = id & ~(HANDLE_DEBUG_TAG_MASK ^ HANDLE_AGE_MASK);
-            // This line is the costly part. In the future, we could potentially use a custom
-            // allocator.
-            mDebugTags[key] = std::move(tag);
-        }
-    }
-
-    utils::CString getHandleTag(HandleBase::HandleId id) const noexcept {
-        if (!isPoolHandle(id)) {
-            return "(no tag)";
-        }
-        uint32_t const key = id & ~(HANDLE_DEBUG_TAG_MASK ^ HANDLE_AGE_MASK);
-        if (auto pos = mDebugTags.find(key); pos != mDebugTags.end()) {
-            return pos->second;
-        }
-        return "(no tag)";
-    }
-
 private:
 
     template<typename D>
@@ -298,8 +240,8 @@ private:
             Node* const pNode = static_cast<Node*>(p);
             uint8_t& expectedAge = pNode[-1].age;
             if (UTILS_UNLIKELY(!mUseAfterFreeCheckDisabled)) {
-                FILAMENT_CHECK_POSTCONDITION(expectedAge == age) <<
-                        "double-free of Handle of size " << size << " at " << p;
+                ASSERT_POSTCONDITION(expectedAge == age,
+                        "double-free of Handle of size %d at %p", size, p);
             }
             expectedAge = (expectedAge + 1) & 0xF; // fixme
 
@@ -364,30 +306,18 @@ private:
         }
     }
 
-    // number if bits allotted to the handle's age (currently 4 max)
-    static constexpr uint32_t HANDLE_AGE_BIT_COUNT = 4;
-    // number if bits allotted to the handle's debug tag (HANDLE_AGE_BIT_COUNT max)
-    static constexpr uint32_t HANDLE_DEBUG_TAG_BIT_COUNT = 2;
-    // bit shift for both the age and debug tag
-    static constexpr uint32_t HANDLE_AGE_SHIFT = 27;
-    // mask for the heap (vs pool) flag
-    static constexpr uint32_t HANDLE_HEAP_FLAG = 0x80000000u;
-    // mask for the age
-    static constexpr uint32_t HANDLE_AGE_MASK =
-            ((1 << HANDLE_AGE_BIT_COUNT) - 1) << HANDLE_AGE_SHIFT;
-    // mask for the debug tag
-    static constexpr uint32_t HANDLE_DEBUG_TAG_MASK =
-            ((1 << HANDLE_DEBUG_TAG_BIT_COUNT) - 1) << HANDLE_AGE_SHIFT;
-    // mask for the index
-    static constexpr uint32_t HANDLE_INDEX_MASK = 0x07FFFFFFu;
-
-    static_assert(HANDLE_DEBUG_TAG_BIT_COUNT <= HANDLE_AGE_BIT_COUNT);
+    // we handle a 4 bits age per address
+    static constexpr uint32_t HANDLE_HEAP_FLAG      = 0x80000000u;      // pool vs heap handle
+    static constexpr uint32_t HANDLE_AGE_MASK       = 0x78000000u;      // handle's age
+    static constexpr uint32_t HANDLE_INDEX_MASK     = 0x07FFFFFFu;      // handle index
+    static constexpr uint32_t HANDLE_TAG_MASK       = HANDLE_AGE_MASK;
+    static constexpr uint32_t HANDLE_AGE_SHIFT      = 27;
 
     static bool isPoolHandle(HandleBase::HandleId id) noexcept {
         return (id & HANDLE_HEAP_FLAG) == 0u;
     }
 
-    HandleBase::HandleId allocateHandleSlow(size_t size);
+    HandleBase::HandleId allocateHandleSlow(size_t size) noexcept;
     void deallocateHandleSlow(HandleBase::HandleId id, size_t size) noexcept;
 
     // We inline this because it's just 4 instructions in the fast case
@@ -396,7 +326,7 @@ private:
         // a non-pool handle.
         if (UTILS_LIKELY(isPoolHandle(id))) {
             char* const base = (char*)mHandleArena.getArea().begin();
-            uint32_t const tag = id & HANDLE_AGE_MASK;
+            uint32_t const tag = id & HANDLE_TAG_MASK;
             size_t const offset = (id & HANDLE_INDEX_MASK) * Allocator::getAlignment();
             return { static_cast<void*>(base + offset), tag };
         }
@@ -411,7 +341,7 @@ private:
         size_t const offset = (char*)p - base;
         assert_invariant((offset % Allocator::getAlignment()) == 0);
         auto id = HandleBase::HandleId(offset / Allocator::getAlignment());
-        id |= tag & HANDLE_AGE_MASK;
+        id |= tag & HANDLE_TAG_MASK;
         assert_invariant((id & HANDLE_HEAP_FLAG) == 0);
         return id;
     }
@@ -421,7 +351,6 @@ private:
     // Below is only used when running out of space in the HandleArena
     mutable utils::Mutex mLock;
     tsl::robin_map<HandleBase::HandleId, void*> mOverflowMap;
-    tsl::robin_map<HandleBase::HandleId, utils::CString> mDebugTags;
     HandleBase::HandleId mId = 0;
     bool mUseAfterFreeCheckDisabled = false;
 };

filament/backend/src/Callable.cpp

@@ -27,8 +27,8 @@ PresentCallable::PresentCallable(PresentFn fn, void* user) noexcept
 }
 
 void PresentCallable::operator()(bool presentFrame) noexcept {
-    FILAMENT_CHECK_PRECONDITION(mPresentFn) << "This PresentCallable was already called. "
-                                               "PresentCallables should be called exactly once.";
+    ASSERT_PRECONDITION(mPresentFn, "This PresentCallable was already called. " \
+            "PresentCallables should be called exactly once.");
     mPresentFn(presentFrame, mUser);
     // Set mPresentFn to nullptr to denote that the callable has been called.
     mPresentFn = nullptr;

filament/backend/src/CircularBuffer.cpp

@@ -24,7 +24,7 @@
 #include <utils/debug.h>
 #include <utils/ostream.h>
 
-#if !defined(WIN32) && !defined(__EMSCRIPTEN__)
+#if !defined(WIN32) && !defined(__EMSCRIPTEN__) && !defined(IOS)
 #    include <sys/mman.h>
 #    include <unistd.h>
 #    define HAS_MMAP 1
@@ -32,11 +32,10 @@
 #    define HAS_MMAP 0
 #endif
 
-#include <stddef.h>
 #include <stdint.h>
-#include <stdio.h>
+#include <stddef.h>
 #include <stdlib.h>
-#include <string.h>
+#include <stdio.h>
 
 using namespace utils;
 
@@ -82,9 +81,6 @@ void* CircularBuffer::alloc(size_t size) noexcept {
             // map the circular buffer once...
             vaddr = mmap(reserve_vaddr, size, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
             if (vaddr != MAP_FAILED) {
-                // populate the address space with pages (because this is a circular buffer,
-                // all the pages will be allocated eventually, might as well do it now)
-                memset(vaddr, 0, size);
                 // and map the circular buffer again, behind the previous copy...
                 vaddr_shadow = mmap((char*)vaddr + size, size,
                         PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
@@ -105,7 +101,7 @@ void* CircularBuffer::alloc(size_t size) noexcept {
     if (UTILS_UNLIKELY(mAshmemFd < 0)) {
         // ashmem failed
         if (vaddr_guard != MAP_FAILED) {
-            munmap(vaddr_guard, BLOCK_SIZE);
+            munmap(vaddr_guard, size);
         }
 
         if (vaddr_shadow != MAP_FAILED) {
@@ -123,11 +119,12 @@ void* CircularBuffer::alloc(size_t size) noexcept {
         data = mmap(nullptr, size * 2 + BLOCK_SIZE,
                 PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
 
-        FILAMENT_CHECK_POSTCONDITION(data != MAP_FAILED) <<
-                "couldn't allocate " << (size * 2 / 1024) <<
-                " KiB of virtual address space for the command buffer";
+        ASSERT_POSTCONDITION(data,
+                "couldn't allocate %u KiB of virtual address space for the command buffer",
+                (size * 2 / 1024));
 
-        slog.w << "Using 'soft' CircularBuffer (" << (size * 2 / 1024) << " KiB)" << io::endl;
+        slog.d << "WARNING: Using soft CircularBuffer (" << (size * 2 / 1024) << " KiB)"
+               << io::endl;
 
         // guard page at the end
         void* guard = (void*)(uintptr_t(data) + size * 2);

filament/backend/src/CommandBufferQueue.cpp

@@ -57,13 +57,7 @@ void CommandBufferQueue::requestExit() {
     mCondition.notify_one();
 }
 
-bool CommandBufferQueue::isPaused() const noexcept {
-    std::lock_guard<utils::Mutex> const lock(mLock);
-    return mPaused;
-}
-
 void CommandBufferQueue::setPaused(bool paused) {
-    std::lock_guard<utils::Mutex> const lock(mLock);
     if (paused) {
         mPaused = true;
     } else {
@@ -74,6 +68,8 @@ void CommandBufferQueue::setPaused(bool paused) {
 
 bool CommandBufferQueue::isExitRequested() const {
     std::lock_guard<utils::Mutex> const lock(mLock);
+    ASSERT_PRECONDITION( mExitRequested == 0 || mExitRequested == EXIT_REQUESTED,
+            "mExitRequested is corrupted (value = 0x%08x)!", mExitRequested);
     return (bool)mExitRequested;
 }
 
@@ -101,23 +97,22 @@ void CommandBufferQueue::flush() noexcept {
     size_t const used = std::distance(
             static_cast<char const*>(begin), static_cast<char const*>(end));
 
-
     std::unique_lock<utils::Mutex> lock(mLock);
-
-    // circular buffer is too small, we corrupted the stream
-    FILAMENT_CHECK_POSTCONDITION(used <= mFreeSpace) <<
-            "Backend CommandStream overflow. Commands are corrupted and unrecoverable.\n"
-            "Please increase minCommandBufferSizeMB inside the Config passed to Engine::create.\n"
-            "Space used at this time: " << used <<
-            " bytes, overflow: " << used - mFreeSpace << " bytes";
-
-    mFreeSpace -= used;
     mCommandBuffersToExecute.push_back({ begin, end });
     mCondition.notify_one();
 
+    // circular buffer is too small, we corrupted the stream
+    ASSERT_POSTCONDITION(used <= mFreeSpace,
+            "Backend CommandStream overflow. Commands are corrupted and unrecoverable.\n"
+            "Please increase minCommandBufferSizeMB inside the Config passed to Engine::create.\n"
+            "Space used at this time: %u bytes, overflow: %u bytes",
+            (unsigned)used, unsigned(used - mFreeSpace));
+
     // wait until there is enough space in the buffer
+    mFreeSpace -= used;
     if (UTILS_UNLIKELY(mFreeSpace < requiredSize)) {
 
+
 #ifndef NDEBUG
         size_t const totalUsed = circularBuffer.size() - mFreeSpace;
         slog.d << "CommandStream used too much space (will block): "
@@ -130,11 +125,6 @@ void CommandBufferQueue::flush() noexcept {
 #endif
 
         SYSTRACE_NAME("waiting: CircularBuffer::flush()");
-
-        FILAMENT_CHECK_POSTCONDITION(!mPaused) <<
-                "CommandStream is full, but since the rendering thread is paused, "
-                "the buffer cannot flush and we will deadlock. Instead, abort.";
-
         mCondition.wait(lock, [this, requiredSize]() -> bool {
             // TODO: on macOS, we need to call pumpEvents from time to time
             return mFreeSpace >= requiredSize;
@@ -150,14 +140,16 @@ std::vector<CommandBufferQueue::Range> CommandBufferQueue::waitForCommands() con
     while ((mCommandBuffersToExecute.empty() || mPaused) && !mExitRequested) {
         mCondition.wait(lock);
     }
+
+    ASSERT_PRECONDITION( mExitRequested == 0 || mExitRequested == EXIT_REQUESTED,
+            "mExitRequested is corrupted (value = 0x%08x)!", mExitRequested);
+
     return std::move(mCommandBuffersToExecute);
 }
 
 void CommandBufferQueue::releaseBuffer(CommandBufferQueue::Range const& buffer) {
-    size_t const used = std::distance(
-            static_cast<char const*>(buffer.begin), static_cast<char const*>(buffer.end));
     std::lock_guard<utils::Mutex> const lock(mLock);
-    mFreeSpace += used;
+    mFreeSpace += uintptr_t(buffer.end) - uintptr_t(buffer.begin);
     mCondition.notify_one();
 }
 

filament/backend/src/CommandStream.cpp

@@ -20,16 +20,11 @@
 #include <utils/CallStack.h>
 #endif
 
-#include <utils/compiler.h>
 #include <utils/Log.h>
-#include <utils/ostream.h>
 #include <utils/Profiler.h>
 #include <utils/Systrace.h>
 
-#include <cstddef>
 #include <functional>
-#include <string>
-#include <utility>
 
 #ifdef __ANDROID__
 #include <sys/system_properties.h>
@@ -79,8 +74,8 @@ CommandStream::CommandStream(Driver& driver, CircularBuffer& buffer) noexcept
 }
 
 void CommandStream::execute(void* buffer) {
-    // NOTE: we can't use SYSTRACE_CALL() or similar here because, execute() below, also
-    // uses systrace BEGIN/END and the END is not guaranteed to be happening in this scope.
+    SYSTRACE_CALL();
+    SYSTRACE_CONTEXT();
 
     Profiler profiler;
 
@@ -105,7 +100,6 @@ void CommandStream::execute(void* buffer) {
             // we want to remove all this when tracing is completely disabled
             profiler.stop();
             UTILS_UNUSED Profiler::Counters const counters = profiler.readCounters();
-            SYSTRACE_CONTEXT();
             SYSTRACE_VALUE32("GLThread (I)", counters.getInstructions());
             SYSTRACE_VALUE32("GLThread (C)", counters.getCpuCycles());
             SYSTRACE_VALUE32("GLThread (CPI x10)", counters.getCPI() * 10);
@@ -155,7 +149,7 @@ void CommandType<void (Driver::*)(ARGS...)>::Command<METHOD>::log() noexcept  {
 
 // ------------------------------------------------------------------------------------------------
 
-void CustomCommand::execute(Driver&, CommandBase* base, intptr_t* next) {
+void CustomCommand::execute(Driver&, CommandBase* base, intptr_t* next) noexcept {
     *next = CustomCommand::align(sizeof(CustomCommand));
     static_cast<CustomCommand*>(base)->mCommand();
     static_cast<CustomCommand*>(base)->~CustomCommand();

filament/backend/src/Driver.cpp

@@ -214,7 +214,7 @@ size_t Driver::getElementTypeSize(ElementType type) noexcept {
 
 Driver::~Driver() noexcept = default;
 
-void Driver::execute(std::function<void(void)> const& fn) {
+void Driver::execute(std::function<void(void)> const& fn) noexcept {
     fn();
 }
 

filament/backend/src/DriverBase.h

@@ -101,14 +101,6 @@ struct HwProgram : public HwBase {
     HwProgram() noexcept = default;
 };
 
-struct HwDescriptorSetLayout : public HwBase {
-    HwDescriptorSetLayout() noexcept = default;
-};
-
-struct HwDescriptorSet : public HwBase {
-    HwDescriptorSet() noexcept = default;
-};
-
 struct HwSamplerGroup : public HwBase {
     HwSamplerGroup() noexcept = default;
 };

filament/backend/src/HandleAllocator.cpp

@@ -80,9 +80,6 @@ HandleAllocator<P0, P1, P2>::HandleAllocator(const char* name, size_t size,
         bool disableUseAfterFreeCheck) noexcept
     : mHandleArena(name, size, disableUseAfterFreeCheck),
       mUseAfterFreeCheckDisabled(disableUseAfterFreeCheck) {
-    // Reserve initial space for debug tags. This prevents excessive calls to malloc when the first
-    // few tags are set.
-    mDebugTags.reserve(512);
 }
 
 template <size_t P0, size_t P1, size_t P2>
@@ -110,15 +107,15 @@ void* HandleAllocator<P0, P1, P2>::handleToPointerSlow(HandleBase::HandleId id)
 }
 
 template <size_t P0, size_t P1, size_t P2>
-HandleBase::HandleId HandleAllocator<P0, P1, P2>::allocateHandleSlow(size_t size) {
+HandleBase::HandleId HandleAllocator<P0, P1, P2>::allocateHandleSlow(size_t size) noexcept {
     void* p = ::malloc(size);
     std::unique_lock lock(mLock);
 
     HandleBase::HandleId id = (++mId) | HANDLE_HEAP_FLAG;
 
-    FILAMENT_CHECK_POSTCONDITION(mId < HANDLE_HEAP_FLAG) <<
+    ASSERT_POSTCONDITION(mId < HANDLE_HEAP_FLAG,
             "No more Handle ids available! This can happen if HandleAllocator arena has been full"
-            " for a while. Please increase FILAMENT_OPENGL_HANDLE_ARENA_SIZE_IN_MB";
+            " for a while. Please increase FILAMENT_OPENGL_HANDLE_ARENA_SIZE_IN_MB");
 
     mOverflowMap.emplace(id, p);
     lock.unlock();

filament/backend/src/PlatformFactory.cpp

@@ -29,25 +29,21 @@
         #include "backend/platforms/PlatformCocoaTouchGL.h"
     #endif
 #elif defined(__APPLE__)
-    #if defined(FILAMENT_SUPPORTS_OPENGL) && !defined(FILAMENT_USE_EXTERNAL_GLES3)
+    #if defined(FILAMENT_SUPPORTS_OPENGL) && !defined(FILAMENT_USE_EXTERNAL_GLES3) && !defined(FILAMENT_USE_SWIFTSHADER)
         #include <backend/platforms/PlatformCocoaGL.h>
     #endif
 #elif defined(__linux__)
     #if defined(FILAMENT_SUPPORTS_X11)
-        #if defined(FILAMENT_SUPPORTS_OPENGL) && !defined(FILAMENT_USE_EXTERNAL_GLES3)
+        #if defined(FILAMENT_SUPPORTS_OPENGL) && !defined(FILAMENT_USE_EXTERNAL_GLES3) && !defined(FILAMENT_USE_SWIFTSHADER)
             #include "backend/platforms/PlatformGLX.h"
         #endif
     #elif defined(FILAMENT_SUPPORTS_EGL_ON_LINUX)
-        #if defined(FILAMENT_SUPPORTS_OPENGL) && !defined(FILAMENT_USE_EXTERNAL_GLES3)
+        #if defined(FILAMENT_SUPPORTS_OPENGL) && !defined(FILAMENT_USE_EXTERNAL_GLES3) && !defined(FILAMENT_USE_SWIFTSHADER)
             #include "backend/platforms/PlatformEGLHeadless.h"
         #endif
-    #elif defined(FILAMENT_SUPPORTS_OSMESA)
-        #if defined(FILAMENT_SUPPORTS_OPENGL) && !defined(FILAMENT_USE_EXTERNAL_GLES3)
-            #include "backend/platforms/PlatformOSMesa.h"
-        #endif
     #endif
 #elif defined(WIN32)
-    #if defined(FILAMENT_SUPPORTS_OPENGL) && !defined(FILAMENT_USE_EXTERNAL_GLES3)
+    #if defined(FILAMENT_SUPPORTS_OPENGL) && !defined(FILAMENT_USE_EXTERNAL_GLES3) && !defined(FILAMENT_USE_SWIFTSHADER)
         #include "backend/platforms/PlatformWGL.h"
     #endif
 #elif defined(__EMSCRIPTEN__)
@@ -115,7 +111,8 @@ Platform* PlatformFactory::create(Backend* backend) noexcept {
     }
     assert_invariant(*backend == Backend::OPENGL);
     #if defined(FILAMENT_SUPPORTS_OPENGL)
-        #if defined(FILAMENT_USE_EXTERNAL_GLES3)
+        #if defined(FILAMENT_USE_EXTERNAL_GLES3) || defined(FILAMENT_USE_SWIFTSHADER)
+            // Swiftshader OpenGLES support is deprecated and incomplete
             return nullptr;
         #elif defined(__ANDROID__)
             return new PlatformEGLAndroid();
@@ -128,8 +125,6 @@ Platform* PlatformFactory::create(Backend* backend) noexcept {
                 return new PlatformGLX();
             #elif defined(FILAMENT_SUPPORTS_EGL_ON_LINUX)
                 return new PlatformEGLHeadless();
-            #elif defined(FILAMENT_SUPPORTS_OSMESA)
-                return new PlatformOSMesa();
             #else
                 return nullptr;
             #endif

filament/backend/src/Program.cpp

@@ -14,25 +14,14 @@
  * limitations under the License.
  */
 
-#include <backend/Program.h>
-#include <backend/DriverEnums.h>
-
-#include <utils/debug.h>
-#include <utils/CString.h>
-#include <utils/ostream.h>
-#include <utils/Invocable.h>
-
-#include <utility>
-
-#include <stddef.h>
-#include <stdint.h>
+#include "backend/Program.h"
 
 namespace filament::backend {
 
 using namespace utils;
 
 // We want these in the .cpp file, so they're not inlined (not worth it)
-Program::Program() noexcept {  // NOLINT(modernize-use-equals-default)
+Program::Program() noexcept { // NOLINT(modernize-use-equals-default)
 }
 
 Program::Program(Program&& rhs) noexcept = default;
@@ -58,36 +47,42 @@ Program& Program::shader(ShaderStage shader, void const* data, size_t size) {
     return *this;
 }
 
-Program& Program::shaderLanguage(ShaderLanguage shaderLanguage) {
-    mShaderLanguage = shaderLanguage;
+Program& Program::uniformBlockBindings(
+        FixedCapacityVector<std::pair<utils::CString, uint8_t>> const& uniformBlockBindings) noexcept {
+    for (auto const& item : uniformBlockBindings) {
+        assert_invariant(item.second < UNIFORM_BINDING_COUNT);
+        mUniformBlocks[item.second] = item.first;
+    }
     return *this;
 }
 
-Program& Program::descriptorBindings(backend::descriptor_set_t set,
-        DescriptorBindingsInfo descriptorBindings) noexcept {
-    mDescriptorBindings[set] = std::move(descriptorBindings);
+Program& Program::uniforms(uint32_t index, UniformInfo const& uniforms) noexcept {
+    assert_invariant(index < UNIFORM_BINDING_COUNT);
+    mBindingUniformInfo[index] = uniforms;
     return *this;
 }
 
-Program& Program::uniforms(uint32_t index, utils::CString name, UniformInfo uniforms) noexcept {
-    mBindingUniformsInfo.reserve(mBindingUniformsInfo.capacity() + 1);
-    mBindingUniformsInfo.emplace_back(index, std::move(name), std::move(uniforms));
-    return *this;
-}
 
-Program& Program::attributes(AttributesInfo attributes) noexcept {
+Program& Program::attributes(
+        utils::FixedCapacityVector<std::pair<utils::CString, uint8_t>> attributes) noexcept {
     mAttributes = std::move(attributes);
     return *this;
 }
 
-Program& Program::specializationConstants(SpecializationConstantsInfo specConstants) noexcept {
-    mSpecializationConstants = std::move(specConstants);
+Program& Program::setSamplerGroup(size_t bindingPoint, ShaderStageFlags stageFlags,
+        const Program::Sampler* samplers, size_t count) noexcept {
+    auto& groupData = mSamplerGroups[bindingPoint];
+    groupData.stageFlags = stageFlags;
+    auto& samplerList = groupData.samplers;
+    samplerList.reserve(count);
+    samplerList.resize(count);
+    std::copy_n(samplers, count, samplerList.data());
     return *this;
 }
 
-Program& Program::pushConstants(ShaderStage stage,
-        utils::FixedCapacityVector<PushConstant> constants) noexcept {
-    mPushConstants[static_cast<uint8_t>(stage)] = std::move(constants);
+Program& Program::specializationConstants(
+        FixedCapacityVector<SpecializationConstant> specConstants) noexcept {
+    mSpecializationConstants = std::move(specConstants);
     return *this;
 }
 
@@ -96,11 +91,6 @@ Program& Program::cacheId(uint64_t cacheId) noexcept {
     return *this;
 }
 
-Program& Program::multiview(bool multiview) noexcept {
-    mMultiview = multiview;
-    return *this;
-}
-
 io::ostream& operator<<(io::ostream& out, const Program& builder) {
     out << "Program{";
     builder.mLogger(out);

filament/backend/src/SystraceProfile.h

@@ -1,28 +0,0 @@
-/*
- * Copyright (C) 2024 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_SYSTRACEPROFILE_H
-#define TNT_FILAMENT_BACKEND_SYSTRACEPROFILE_H
-
-#include <utils/Systrace.h>
-
-#define PROFILE_SCOPE(marker)       SYSTRACE_NAME(marker)
-
-#define PROFILE_NAME_BEGINFRAME    "backend::beginFrame"
-#define PROFILE_NAME_ENDFRAME      "backend::endFrame"
-
-#endif // TNT_FILAMENT_BACKEND_SYSTRACEPROFILE_H
-

filament/backend/src/VirtualMachineEnv.cpp

@@ -16,23 +16,13 @@
 
 #include "private/backend/VirtualMachineEnv.h"
 
-#include <utils/compiler.h>
 #include <utils/debug.h>
 
-#include <jni.h>
-
 namespace filament {
 
 JavaVM* VirtualMachineEnv::sVirtualMachine = nullptr;
 
-/*
- * This is typically called by filament_jni.so when it is loaded. If filament_jni.so is not used,
- * then this must be called manually -- however, this is a problem because VirtualMachineEnv.h
- * is currently private and part of backend.
- * For now, we authorize this usage, but we will need to fix it; by making a proper public
- * API for this.
- */
-UTILS_PUBLIC
+// This is called when the library is loaded. We need this to get a reference to the global VM
 UTILS_NOINLINE
 jint VirtualMachineEnv::JNI_OnLoad(JavaVM* vm) noexcept {
     JNIEnv* env = nullptr;

filament/backend/src/metal/MetalBlitter.mm

@@ -109,8 +109,9 @@ inline bool MTLSizeEqual(T a, T b) noexcept {
 MetalBlitter::MetalBlitter(MetalContext& context) noexcept : mContext(context) { }
 
 void MetalBlitter::blit(id<MTLCommandBuffer> cmdBuffer, const BlitArgs& args, const char* label) {
-    FILAMENT_CHECK_PRECONDITION(args.source.region.size.depth == args.destination.region.size.depth)
-            << "Blitting requires the source and destination regions to have the same depth.";
+
+    ASSERT_PRECONDITION(args.source.region.size.depth == args.destination.region.size.depth,
+            "Blitting requires the source and destination regions to have the same depth.");
 
     // Determine if the blit for color or depth are eligible to use a MTLBlitCommandEncoder.
     // blitFastPath returns true upon success.
@@ -326,8 +327,7 @@ id<MTLFunction> MetalBlitter::compileFragmentFunction(BlitFunctionKey key) const
             utils::slog.e << description << utils::io::endl;
         }
     }
-    FILAMENT_CHECK_POSTCONDITION(library && function)
-            << "Unable to compile fragment shader for MetalBlitter.";
+    ASSERT_POSTCONDITION(library && function, "Unable to compile fragment shader for MetalBlitter.");
 
     return function;
 }
@@ -352,8 +352,7 @@ id<MTLFunction> MetalBlitter::getBlitVertexFunction() {
             utils::slog.e << description << utils::io::endl;
         }
     }
-    FILAMENT_CHECK_POSTCONDITION(library && function)
-            << "Unable to compile vertex shader for MetalBlitter.";
+    ASSERT_POSTCONDITION(library && function, "Unable to compile vertex shader for MetalBlitter.");
 
     mVertexFunction = function;
 

filament/backend/src/metal/MetalBuffer.h

@@ -18,7 +18,6 @@
 #define TNT_FILAMENT_DRIVER_METALBUFFER_H
 
 #include "MetalContext.h"
-#include "MetalPlatform.h"
 
 #include <backend/DriverEnums.h>
 
@@ -29,91 +28,20 @@
 #include <utility>
 #include <memory>
 #include <atomic>
-#include <chrono>
 
 namespace filament::backend {
 
-class ScopedAllocationTimer {
-public:
-    ScopedAllocationTimer(const char* name) : mBeginning(clock_t::now()), mName(name) {}
-    ~ScopedAllocationTimer() {
-        using namespace std::literals::chrono_literals;
-        static constexpr std::chrono::seconds LONG_TIME_THRESHOLD = 10s;
-
-        auto end = clock_t::now();
-        std::chrono::duration<double, std::micro> allocationTimeMicroseconds = end - mBeginning;
-
-        if (UTILS_UNLIKELY(allocationTimeMicroseconds > LONG_TIME_THRESHOLD)) {
-            if (platform && platform->hasDebugUpdateStatFunc()) {
-                char buffer[64];
-                snprintf(buffer, sizeof(buffer), "filament.metal.long_buffer_allocation_time.%s",
-                        mName);
-                platform->debugUpdateStat(
-                        buffer, static_cast<uint64_t>(allocationTimeMicroseconds.count()));
-            }
-        }
-    }
-
-    static void setPlatform(MetalPlatform* p) { platform = p; }
-
-private:
-    typedef std::chrono::steady_clock clock_t;
-
-    static MetalPlatform* platform;
-
-    std::chrono::time_point<clock_t> mBeginning;
-    const char* mName;
-};
-
 class TrackedMetalBuffer {
 public:
-
-    static constexpr size_t EXCESS_BUFFER_COUNT = 30000;
-
-    enum class Type {
-        NONE = 0,
-        GENERIC = 1,
-        RING = 2,       // deprecated
-        STAGING = 3,
-        DESCRIPTOR_SET = 4,
-    };
-    static constexpr size_t TypeCount = 4;
-
-    static constexpr auto toIndex(Type t) {
-        assert_invariant(t != Type::NONE);
-        switch (t) {
-            case Type::NONE:
-            case Type::GENERIC:
-                return 0;
-            case Type::RING:
-                return 1;
-            case Type::STAGING:
-                return 2;
-            case Type::DESCRIPTOR_SET:
-                return 3;
-        }
-    }
-
     TrackedMetalBuffer() noexcept : mBuffer(nil) {}
-    TrackedMetalBuffer(nullptr_t) noexcept : mBuffer(nil) {}
-    TrackedMetalBuffer(id<MTLBuffer> buffer, Type type) : mBuffer(buffer), mType(type) {
-        assert_invariant(type != Type::NONE);
+    TrackedMetalBuffer(id<MTLBuffer> buffer) noexcept : mBuffer(buffer) {
         if (buffer) {
-            aliveBuffers[toIndex(type)]++;
-            mType = type;
-            if (getAliveBuffers() >= EXCESS_BUFFER_COUNT) {
-                if (platform && platform->hasDebugUpdateStatFunc()) {
-                    platform->debugUpdateStat("filament.metal.excess_buffers_allocated",
-                            TrackedMetalBuffer::getAliveBuffers());
-                }
-            }
+            aliveBuffers++;
         }
     }
-
     ~TrackedMetalBuffer() {
         if (mBuffer) {
-            assert_invariant(mType != Type::NONE);
-            aliveBuffers[toIndex(mType)]--;
+            aliveBuffers--;
         }
     }
 
@@ -129,31 +57,18 @@ public:
     id<MTLBuffer> get() const noexcept { return mBuffer; }
     operator bool() const noexcept { return bool(mBuffer); }
 
-    static uint64_t getAliveBuffers() {
-        uint64_t sum = 0;
-        for (const auto& v : aliveBuffers) {
-            sum += v;
-        }
-        return sum;
-    }
-
-    static uint64_t getAliveBuffers(Type type) {
-        assert_invariant(type != Type::NONE);
-        return aliveBuffers[toIndex(type)];
-    }
-    static void setPlatform(MetalPlatform* p) { platform = p; }
+    static uint64_t getAliveBuffers() { return aliveBuffers; }
 
 private:
     void swap(TrackedMetalBuffer& other) noexcept {
-        std::swap(mBuffer, other.mBuffer);
-        std::swap(mType, other.mType);
+        id<MTLBuffer> temp = mBuffer;
+        mBuffer = other.mBuffer;
+        other.mBuffer = temp;
     }
 
     id<MTLBuffer> mBuffer;
-    Type mType = Type::NONE;
 
-    static MetalPlatform* platform;
-    static std::array<uint64_t, TypeCount> aliveBuffers;
+    static std::atomic<uint64_t> aliveBuffers;
 };
 
 class MetalBuffer {
@@ -163,8 +78,6 @@ public:
          size_t size, bool forceGpuBuffer = false);
     ~MetalBuffer();
 
-    [[nodiscard]] bool wasAllocationSuccessful() const noexcept { return mBuffer || mCpuBuffer; }
-
     MetalBuffer(const MetalBuffer& rhs) = delete;
     MetalBuffer& operator=(const MetalBuffer& rhs) = delete;
 
@@ -174,10 +87,8 @@ public:
      * Update the buffer with data inside src. Potentially allocates a new buffer allocation to hold
      * the bytes which will be released when the current frame is finished.
      */
-    using TagResolver = utils::Invocable<const char*(void)>;
-    void copyIntoBuffer(void* src, size_t size, size_t byteOffset, TagResolver&& getHandleTag);
-    void copyIntoBufferUnsynchronized(
-            void* src, size_t size, size_t byteOffset, TagResolver&& getHandleTag);
+    void copyIntoBuffer(void* src, size_t size, size_t byteOffset);
+    void copyIntoBufferUnsynchronized(void* src, size_t size, size_t byteOffset);
 
     /**
      * Denotes that this buffer is used for a draw call ensuring that its allocation remains valid
@@ -187,7 +98,7 @@ public:
      * is no device allocation.
      *
      */
-    id<MTLBuffer> getGpuBufferForDraw() noexcept;
+    id<MTLBuffer> getGpuBufferForDraw(id<MTLCommandBuffer> cmdBuffer) noexcept;
 
     void* getCpuBuffer() const noexcept { return mCpuBuffer; }
 
@@ -211,17 +122,6 @@ public:
 
 private:
 
-    enum class UploadStrategy {
-        POOL,
-        BUMP_ALLOCATOR,
-    };
-
-    void uploadWithPoolBuffer(
-            void* src, size_t size, size_t byteOffset, TagResolver&& getHandleTag) const;
-    void uploadWithBumpAllocator(
-            void* src, size_t size, size_t byteOffset, TagResolver&& getHandleTag) const;
-
-    UploadStrategy mUploadStrategy;
     TrackedMetalBuffer mBuffer;
     size_t mBufferSize = 0;
     void* mCpuBuffer = nullptr;
@@ -271,9 +171,7 @@ public:
           mBufferOptions(options),
           mSlotSizeBytes(computeSlotSize(layout)),
           mSlotCount(slotCount) {
-        ScopedAllocationTimer timer("ring");
-        mBuffer = { [device newBufferWithLength:mSlotSizeBytes * mSlotCount options:mBufferOptions],
-            TrackedMetalBuffer::Type::RING };
+        mBuffer = [device newBufferWithLength:mSlotSizeBytes * mSlotCount options:mBufferOptions];
         assert_invariant(mBuffer);
     }
 
@@ -291,13 +189,9 @@ public:
             // If we already have an aux buffer, it will get freed here, unless it has been retained
             // by a MTLCommandBuffer. In that case, it will be freed when the command buffer
             // finishes executing.
-            {
-                ScopedAllocationTimer timer("ring");
-                mAuxBuffer = { [mDevice newBufferWithLength:mSlotSizeBytes options:mBufferOptions],
-                    TrackedMetalBuffer::Type::RING };
-            }
+            mAuxBuffer = [mDevice newBufferWithLength:mSlotSizeBytes options:mBufferOptions];
             assert_invariant(mAuxBuffer);
-            return { mAuxBuffer.get(), 0 };
+            return {mAuxBuffer.get(), 0};
         }
         mCurrentSlot = (mCurrentSlot + 1) % mSlotCount;
         mOccupiedSlots->fetch_add(1, std::memory_order_relaxed);

filament/backend/src/metal/MetalBuffer.mm

@@ -22,42 +22,23 @@
 namespace filament {
 namespace backend {
 
-std::array<uint64_t, TrackedMetalBuffer::TypeCount> TrackedMetalBuffer::aliveBuffers = { 0 };
-MetalPlatform* TrackedMetalBuffer::platform = nullptr;
-MetalPlatform* ScopedAllocationTimer::platform = nullptr;
+std::atomic<uint64_t> TrackedMetalBuffer::aliveBuffers = 0;
 
 MetalBuffer::MetalBuffer(MetalContext& context, BufferObjectBinding bindingType, BufferUsage usage,
-        size_t size, bool forceGpuBuffer)
-    : mBufferSize(size), mContext(context) {
-    const MetalBumpAllocator& allocator = *mContext.bumpAllocator;
-    // VERTEX is also used for index buffers
-    if (allocator.getCapacity() > 0 && bindingType == BufferObjectBinding::VERTEX) {
-        mUploadStrategy = UploadStrategy::BUMP_ALLOCATOR;
-    } else {
-        mUploadStrategy = UploadStrategy::POOL;
-    }
-
+        size_t size, bool forceGpuBuffer) : mBufferSize(size), mContext(context) {
     // If the buffer is less than 4K in size and is updated frequently, we don't use an explicit
     // buffer. Instead, we use immediate command encoder methods like setVertexBytes:length:atIndex:.
     // This won't work for SSBOs, since they are read/write.
-
-    /*
     if (size <= 4 * 1024 && bindingType != BufferObjectBinding::SHADER_STORAGE &&
             usage == BufferUsage::DYNAMIC && !forceGpuBuffer) {
         mBuffer = nil;
         mCpuBuffer = malloc(size);
         return;
     }
-    */
 
     // Otherwise, we allocate a private GPU buffer.
-    {
-        ScopedAllocationTimer timer("generic");
-        mBuffer = { [context.device newBufferWithLength:size options:MTLResourceStorageModePrivate],
-            TrackedMetalBuffer::Type::GENERIC };
-    }
-    // mBuffer might fail to be allocated. Clients can check for this by calling
-    // wasAllocationSuccessful().
+    mBuffer = [context.device newBufferWithLength:size options:MTLResourceStorageModePrivate];
+    ASSERT_POSTCONDITION(mBuffer, "Could not allocate Metal buffer of size %zu.", size);
 }
 
 MetalBuffer::~MetalBuffer() {
@@ -66,44 +47,49 @@ MetalBuffer::~MetalBuffer() {
     }
 }
 
-void MetalBuffer::copyIntoBuffer(
-        void* src, size_t size, size_t byteOffset, TagResolver&& getHandleTag) {
+void MetalBuffer::copyIntoBuffer(void* src, size_t size, size_t byteOffset) {
     if (size <= 0) {
         return;
     }
+    ASSERT_PRECONDITION(size + byteOffset <= mBufferSize,
+            "Attempting to copy %zu bytes into a buffer of size %zu at offset %zu",
+            size, mBufferSize, byteOffset);
 
-    FILAMENT_CHECK_PRECONDITION(src)
-            << "copyIntoBuffer called with a null src, tag=" << getHandleTag();
-    FILAMENT_CHECK_PRECONDITION(size + byteOffset <= mBufferSize)
-            << "Attempting to copy " << size << " bytes into a buffer of size " << mBufferSize
-            << " at offset " << byteOffset << ", tag=" << getHandleTag();
-    // The copy blit requires that byteOffset be a multiple of 4.
-    FILAMENT_CHECK_PRECONDITION(!(byteOffset & 0x3))
-            << "byteOffset must be a multiple of 4, tag=" << getHandleTag();
-
-    // If we have a cpu buffer, we can directly copy into it.
+    // Either copy into the Metal buffer or into our cpu buffer.
     if (mCpuBuffer) {
         memcpy(static_cast<uint8_t*>(mCpuBuffer) + byteOffset, src, size);
         return;
     }
 
-    switch (mUploadStrategy) {
-        case UploadStrategy::BUMP_ALLOCATOR:
-            uploadWithBumpAllocator(src, size, byteOffset, std::move(getHandleTag));
-            break;
-        case UploadStrategy::POOL:
-            uploadWithPoolBuffer(src, size, byteOffset, std::move(getHandleTag));
-            break;
-    }
+    // Acquire a staging buffer to hold the contents of this update.
+    MetalBufferPool* bufferPool = mContext.bufferPool;
+    const MetalBufferPoolEntry* const staging = bufferPool->acquireBuffer(size);
+    memcpy(staging->buffer.get().contents, src, size);
+
+    // The blit below requires that byteOffset be a multiple of 4.
+    ASSERT_PRECONDITION(!(byteOffset & 0x3u), "byteOffset must be a multiple of 4");
+
+    // Encode a blit from the staging buffer into the private GPU buffer.
+    id<MTLCommandBuffer> cmdBuffer = getPendingCommandBuffer(&mContext);
+    id<MTLBlitCommandEncoder> blitEncoder = [cmdBuffer blitCommandEncoder];
+    blitEncoder.label = @"Buffer upload blit";
+    [blitEncoder copyFromBuffer:staging->buffer.get()
+                   sourceOffset:0
+                       toBuffer:mBuffer.get()
+              destinationOffset:byteOffset
+                           size:size];
+    [blitEncoder endEncoding];
+    [cmdBuffer addCompletedHandler:^(id<MTLCommandBuffer> cb) {
+        bufferPool->releaseBuffer(staging);
+    }];
 }
 
-void MetalBuffer::copyIntoBufferUnsynchronized(
-        void* src, size_t size, size_t byteOffset, TagResolver&& getHandleTag) {
+void MetalBuffer::copyIntoBufferUnsynchronized(void* src, size_t size, size_t byteOffset) {
     // TODO: implement the unsynchronized version
-    copyIntoBuffer(src, size, byteOffset, std::move(getHandleTag));
+    copyIntoBuffer(src, size, byteOffset);
 }
 
-id<MTLBuffer> MetalBuffer::getGpuBufferForDraw() noexcept {
+id<MTLBuffer> MetalBuffer::getGpuBufferForDraw(id<MTLCommandBuffer> cmdBuffer) noexcept {
     // If there's a CPU buffer, then we return nil here, as the CPU-side buffer will be bound
     // separately.
     if (mCpuBuffer) {
@@ -146,7 +132,7 @@ void MetalBuffer::bindBuffers(id<MTLCommandBuffer> cmdBuffer, id<MTLCommandEncod
         }
         // getGpuBufferForDraw() might return nil, which means there isn't a device allocation for
         // this buffer. In this case, we'll bind the buffer below with the CPU-side memory.
-        id<MTLBuffer> gpuBuffer = buffer->getGpuBufferForDraw();
+        id<MTLBuffer> gpuBuffer = buffer->getGpuBufferForDraw(cmdBuffer);
         if (!gpuBuffer) {
             continue;
         }
@@ -206,54 +192,5 @@ void MetalBuffer::bindBuffers(id<MTLCommandBuffer> cmdBuffer, id<MTLCommandEncod
     }
 }
 
-void MetalBuffer::uploadWithPoolBuffer(
-        void* src, size_t size, size_t byteOffset, TagResolver&& getHandleTag) const {
-    MetalBufferPool* bufferPool = mContext.bufferPool;
-    const MetalBufferPoolEntry* const staging = bufferPool->acquireBuffer(size);
-    FILAMENT_CHECK_POSTCONDITION(staging)
-            << "uploadWithPoolbuffer unable to acquire staging buffer of size " << size
-            << ", tag=" << getHandleTag();
-    memcpy(staging->buffer.get().contents, src, size);
-
-    // Encode a blit from the staging buffer into the private GPU buffer.
-    id<MTLCommandBuffer> cmdBuffer = getPendingCommandBuffer(&mContext);
-    id<MTLBlitCommandEncoder> blitEncoder = [cmdBuffer blitCommandEncoder];
-    blitEncoder.label = @"Buffer upload blit - pool buffer";
-    [blitEncoder copyFromBuffer:staging->buffer.get()
-                   sourceOffset:0
-                       toBuffer:mBuffer.get()
-              destinationOffset:byteOffset
-                           size:size];
-    [blitEncoder endEncoding];
-    [cmdBuffer addCompletedHandler:^(id<MTLCommandBuffer> cb) {
-        bufferPool->releaseBuffer(staging);
-    }];
-}
-
-void MetalBuffer::uploadWithBumpAllocator(
-        void* src, size_t size, size_t byteOffset, TagResolver&& getHandleTag) const {
-    MetalBumpAllocator& allocator = *mContext.bumpAllocator;
-    auto [buffer, offset] = allocator.allocateStagingArea(size);
-    FILAMENT_CHECK_POSTCONDITION(buffer)
-            << "uploadWithBumpAllocator unable to acquire staging area of size " << size
-            << ", tag=" << getHandleTag();
-    void* const contents = buffer.contents;
-    FILAMENT_CHECK_POSTCONDITION(contents)
-            << "uploadWithBumpAllocator unable to acquire pointer to staging area, size " << size
-            << ", tag=" << getHandleTag();
-    memcpy(static_cast<char*>(contents) + offset, src, size);
-
-    // Encode a blit from the staging buffer into the private GPU buffer.
-    id<MTLCommandBuffer> cmdBuffer = getPendingCommandBuffer(&mContext);
-    id<MTLBlitCommandEncoder> blitEncoder = [cmdBuffer blitCommandEncoder];
-    blitEncoder.label = @"Buffer upload blit - bump allocator";
-    [blitEncoder copyFromBuffer:buffer
-                   sourceOffset:offset
-                       toBuffer:mBuffer.get()
-              destinationOffset:byteOffset
-                           size:size];
-    [blitEncoder endEncoding];
-}
-
 } // namespace backend
 } // namespace filament

filament/backend/src/metal/MetalBufferPool.h

@@ -38,28 +38,6 @@ struct MetalBufferPoolEntry {
     mutable uint32_t referenceCount;
 };
 
-class MetalBumpAllocator {
-public:
-    MetalBumpAllocator(id<MTLDevice> device, size_t capacity);
-
-    /**
-     * Allocates a staging area of the given size. Returns a pair of the buffer and the offset
-     * within the buffer. The buffer is guaranteed to be at least the given size, but may be larger.
-     * Clients must not write to the buffer beyond the returned offset + size.
-     * Clients are responsible for holding a reference to the returned buffer.
-     * Allocations are guaranteed to be aligned to 4 bytes.
-     */
-    std::pair<id<MTLBuffer>, size_t> allocateStagingArea(size_t size);
-
-    size_t getCapacity() const noexcept { return mCapacity; }
-
-private:
-    id<MTLDevice> mDevice;
-    TrackedMetalBuffer mCurrentUploadBuffer = nil;
-    size_t mHead = 0;
-    size_t mCapacity;
-};
-
 // Manages a pool of Metal buffers, periodically releasing ones that have been unused for awhile.
 class MetalBufferPool {
 public:

filament/backend/src/metal/MetalBufferPool.mm

@@ -42,16 +42,11 @@ MetalBufferPoolEntry const* MetalBufferPool::acquireBuffer(size_t numBytes) {
     }
 
     // We were not able to find a sufficiently large stage, so create a new one.
-    id<MTLBuffer> buffer = nil;
-    {
-        ScopedAllocationTimer timer("staging");
-        buffer = [mContext.device newBufferWithLength:numBytes
-                                              options:MTLResourceStorageModeShared];
-    }
-    FILAMENT_CHECK_POSTCONDITION(buffer)
-            << "Could not allocate Metal staging buffer of size " << numBytes << ".";
+    id<MTLBuffer> buffer = [mContext.device newBufferWithLength:numBytes
+                                                        options:MTLResourceStorageModeShared];
+    ASSERT_POSTCONDITION(buffer, "Could not allocate Metal staging buffer of size %zu.", numBytes);
     MetalBufferPoolEntry* stage = new MetalBufferPoolEntry {
-        .buffer = { buffer, TrackedMetalBuffer::Type::STAGING },
+        .buffer = buffer,
         .capacity = numBytes,
         .lastAccessed = mCurrentFrame,
         .referenceCount = 1
@@ -116,39 +111,5 @@ void MetalBufferPool::reset() noexcept {
     mFreeStages.clear();
 }
 
-MetalBumpAllocator::MetalBumpAllocator(id<MTLDevice> device, size_t capacity)
-    : mDevice(device), mCapacity(capacity) {
-    if (mCapacity > 0) {
-        mCurrentUploadBuffer = { [device newBufferWithLength:capacity options:MTLStorageModeShared],
-            TrackedMetalBuffer::Type::STAGING };
-    }
-}
-
-std::pair<id<MTLBuffer>, size_t> MetalBumpAllocator::allocateStagingArea(size_t size) {
-    if (size == 0) {
-        return { nil, 0 };
-    }
-    if (size > mCapacity) {
-        return { [mDevice newBufferWithLength:size options:MTLStorageModeShared], 0 };
-    }
-    assert_invariant(mCurrentUploadBuffer);
-
-    // Align the head to a 4-byte boundary.
-    mHead = (mHead + 3) & ~3;
-
-    if (UTILS_LIKELY(mHead + size <= mCapacity)) {
-        const size_t oldHead = mHead;
-        mHead += size;
-        return { mCurrentUploadBuffer.get(), oldHead };
-    }
-
-    // We're finished with the current allocation.
-    mCurrentUploadBuffer = { [mDevice newBufferWithLength:mCapacity options:MTLStorageModeShared],
-        TrackedMetalBuffer::Type::STAGING };
-    mHead = size;
-
-    return { mCurrentUploadBuffer.get(), 0 };
-}
-
 } // namespace backend
 } // namespace filament

filament/backend/src/metal/MetalContext.h

@@ -21,8 +21,6 @@
 #include "MetalShaderCompiler.h"
 #include "MetalState.h"
 
-#include <backend/DriverEnums.h>
-
 #include <CoreVideo/CVMetalTextureCache.h>
 #include <Metal/Metal.h>
 #include <QuartzCore/QuartzCore.h>
@@ -46,88 +44,27 @@ namespace backend {
 class MetalDriver;
 class MetalBlitter;
 class MetalBufferPool;
-class MetalBumpAllocator;
 class MetalRenderTarget;
+class MetalSamplerGroup;
 class MetalSwapChain;
 class MetalTexture;
 class MetalTimerQueryInterface;
 struct MetalUniformBuffer;
 struct MetalIndexBuffer;
 struct MetalVertexBuffer;
-struct MetalDescriptorSet;
 
 constexpr static uint8_t MAX_SAMPLE_COUNT = 8;  // Metal devices support at most 8 MSAA samples
 
-class MetalPushConstantBuffer {
-public:
-    void setPushConstant(PushConstantVariant value, uint8_t index);
-    bool isDirty() const { return mDirty; }
-    void setBytes(id<MTLCommandEncoder> encoder, ShaderStage stage);
-    void clear();
-
-private:
-    std::vector<PushConstantVariant> mPushConstants;
-    bool mDirty = false;
-};
-
-class MetalDynamicOffsets {
-public:
-    void setOffsets(uint32_t set, const uint32_t* offsets, uint32_t count) {
-        assert(set < MAX_DESCRIPTOR_SET_COUNT);
-
-        auto getStartIndexForSet = [&](uint32_t s) {
-            uint32_t startIndex = 0;
-            for (uint32_t i = 0; i < s; i++) {
-                startIndex += mCounts[i];
-            }
-            return startIndex;
-        };
-
-        const bool resizeNecessary = mCounts[set] != count;
-        if (UTILS_UNLIKELY(resizeNecessary)) {
-            int delta = count - mCounts[set];
-
-            auto thisSetStart = mOffsets.begin() + getStartIndexForSet(set);
-            if (delta > 0) {
-                mOffsets.insert(thisSetStart, delta, 0);
-            } else {
-                mOffsets.erase(thisSetStart, thisSetStart - delta);
-            }
-
-            mCounts[set] = count;
-        }
-
-        if (resizeNecessary ||
-                !std::equal(
-                        offsets, offsets + count, mOffsets.begin() + getStartIndexForSet(set))) {
-            std::copy(offsets, offsets + count, mOffsets.begin() + getStartIndexForSet(set));
-            mDirty = true;
-        }
-    }
-    bool isDirty() const { return mDirty; }
-    void setDirty(bool dirty) { mDirty = dirty; }
-
-    std::pair<uint32_t, const uint32_t*> getOffsets() const {
-        return { mOffsets.size(), mOffsets.data() };
-    }
-
-private:
-    std::array<uint32_t, MAX_DESCRIPTOR_SET_COUNT> mCounts = { 0 };
-    std::vector<uint32_t> mOffsets;
-    bool mDirty = false;
-};
-
 struct MetalContext {
+    explicit MetalContext(size_t metalFreedTextureListSize)
+        : texturesToDestroy(metalFreedTextureListSize) {}
+
     MetalDriver* driver;
     id<MTLDevice> device = nullptr;
     id<MTLCommandQueue> commandQueue = nullptr;
 
-    // The ID of pendingCommandBuffer (or the next command buffer, if pendingCommandBuffer is nil).
-    uint64_t pendingCommandBufferId = 1;
-    // read from driver thread, set from completion handlers
-    std::atomic<uint64_t> latestCompletedCommandBufferId = 0;
-    id<MTLCommandBuffer> pendingCommandBuffer = nil;
-    id<MTLRenderCommandEncoder> currentRenderPassEncoder = nil;
+    id<MTLCommandBuffer> pendingCommandBuffer = nullptr;
+    id<MTLRenderCommandEncoder> currentRenderPassEncoder = nullptr;
 
     std::atomic<bool> memorylessLimitsReached = false;
 
@@ -143,7 +80,7 @@ struct MetalContext {
     } highestSupportedGpuFamily;
 
     struct {
-        bool staticTextureTargetError;
+        bool a8xStaticTextureTargetError;
     } bugs;
 
     // sampleCountLookup[requestedSamples] gives a <= sample count supported by the device.
@@ -158,10 +95,10 @@ struct MetalContext {
     // State trackers.
     PipelineStateTracker pipelineState;
     DepthStencilStateTracker depthStencilState;
+    std::array<BufferState, Program::UNIFORM_BINDING_COUNT> uniformState;
+    std::array<BufferState, MAX_SSBO_COUNT> ssboState;
     CullModeStateTracker cullModeState;
     WindingStateTracker windingState;
-    DepthClampStateTracker depthClampState;
-    ScissorRectStateTracker scissorRectState;
     Handle<HwRenderPrimitive> currentRenderPrimitive;
 
     // State caches.
@@ -172,21 +109,24 @@ struct MetalContext {
 
     PolygonOffset currentPolygonOffset = {0.0f, 0.0f};
 
-    std::array<MetalPushConstantBuffer, Program::SHADER_TYPE_COUNT> currentPushConstants;
+    MetalSamplerGroup* samplerBindings[Program::SAMPLER_BINDING_COUNT] = {};
 
-    // Keeps track of descriptor sets we've finalized for the current render pass.
-    tsl::robin_set<MetalDescriptorSet*> finalizedDescriptorSets;
-    std::array<MetalDescriptorSet*, MAX_DESCRIPTOR_SET_COUNT> currentDescriptorSets = {};
-    MetalBufferBindings<MAX_DESCRIPTOR_SET_COUNT, ShaderStage::VERTEX> vertexDescriptorBindings;
-    MetalBufferBindings<MAX_DESCRIPTOR_SET_COUNT, ShaderStage::FRAGMENT> fragmentDescriptorBindings;
-    MetalBufferBindings<MAX_DESCRIPTOR_SET_COUNT, ShaderStage::COMPUTE> computeDescriptorBindings;
-    MetalDynamicOffsets dynamicOffsets;
+    // Keeps track of sampler groups we've finalized for the current render pass.
+    tsl::robin_set<MetalSamplerGroup*> finalizedSamplerGroups;
 
-    // Keeps track of all alive textures.
+    // Keeps track of all alive sampler groups, textures.
+    tsl::robin_set<MetalSamplerGroup*> samplerGroups;
     tsl::robin_set<MetalTexture*> textures;
 
+    // This circular buffer implements delayed destruction for Metal texture handles. It keeps a
+    // handle to a fixed number of the most recently destroyed texture handles. When we're asked to
+    // destroy a texture handle, we free its texture memory, but keep the MetalTexture object alive,
+    // marking it as "terminated". If we later are asked to use that texture, we can check its
+    // terminated status and throw an Objective-C error instead of crashing, which is helpful for
+    // debugging use-after-free issues in release builds.
+    utils::FixedCircularBuffer<Handle<HwTexture>> texturesToDestroy;
+
     MetalBufferPool* bufferPool;
-    MetalBumpAllocator* bumpAllocator;
 
     MetalSwapChain* currentDrawSwapChain = nil;
     MetalSwapChain* currentReadSwapChain = nil;
@@ -197,7 +137,6 @@ struct MetalContext {
 
     // Empty texture used to prevent GPU errors when a sampler has been bound without a texture.
     id<MTLTexture> emptyTexture = nil;
-    id<MTLBuffer> emptyBuffer = nil;
 
     MetalBlitter* blitter = nullptr;
 

filament/backend/src/metal/MetalContext.mm

@@ -101,14 +101,9 @@ id<MTLCommandBuffer> getPendingCommandBuffer(MetalContext* context) {
     context->pendingCommandBuffer = [context->commandQueue commandBuffer];
     // It's safe for this block to capture the context variable. MetalDriver::terminate will ensure
     // all frames and their completion handlers finish before context is deallocated.
-    uint64_t thisCommandBufferId = context->pendingCommandBufferId;
     [context->pendingCommandBuffer addCompletedHandler:^(id <MTLCommandBuffer> buffer) {
         context->resourceTracker.clearResources((__bridge void*) buffer);
-
-        // Command buffers should complete in order, so latestCompletedCommandBufferId will only
-        // ever increase.
-        context->latestCompletedCommandBufferId = thisCommandBufferId;
-
+        
         auto errorCode = (MTLCommandBufferError)buffer.error.code;
         if (@available(macOS 11.0, *)) {
             if (errorCode == MTLCommandBufferErrorMemoryless) {
@@ -118,8 +113,7 @@ id<MTLCommandBuffer> getPendingCommandBuffer(MetalContext* context) {
             }
         }
     }];
-    FILAMENT_CHECK_POSTCONDITION(context->pendingCommandBuffer)
-            << "Could not obtain command buffer.";
+    ASSERT_POSTCONDITION(context->pendingCommandBuffer, "Could not obtain command buffer.");
     return context->pendingCommandBuffer;
 }
 
@@ -130,7 +124,6 @@ void submitPendingCommands(MetalContext* context) {
     assert_invariant(context->pendingCommandBuffer.status != MTLCommandBufferStatusCommitted);
     [context->pendingCommandBuffer commit];
     context->pendingCommandBuffer = nil;
-    context->pendingCommandBufferId++;
 }
 
 id<MTLTexture> getOrCreateEmptyTexture(MetalContext* context) {
@@ -160,67 +153,5 @@ bool isInRenderPass(MetalContext* context) {
     return context->currentRenderPassEncoder != nil;
 }
 
-void MetalPushConstantBuffer::setPushConstant(PushConstantVariant value, uint8_t index) {
-    if (mPushConstants.size() <= index) {
-        mPushConstants.resize(index + 1);
-        mDirty = true;
-    }
-    if (UTILS_LIKELY(mPushConstants[index] != value)) {
-        mDirty = true;
-        mPushConstants[index] = value;
-    }
-}
-
-void MetalPushConstantBuffer::setBytes(id<MTLCommandEncoder> encoder, ShaderStage stage) {
-    constexpr size_t PUSH_CONSTANT_SIZE_BYTES = 4;
-
-    static char buffer[MAX_PUSH_CONSTANT_COUNT * PUSH_CONSTANT_SIZE_BYTES];
-    assert_invariant(mPushConstants.size() <= MAX_PUSH_CONSTANT_COUNT);
-
-    size_t bufferSize = PUSH_CONSTANT_SIZE_BYTES * mPushConstants.size();
-    for (size_t i = 0; i < mPushConstants.size(); i++) {
-        const auto& constant = mPushConstants[i];
-        std::visit(
-                [i](auto arg) {
-                    if constexpr (std::is_same_v<decltype(arg), bool>) {
-                        // bool push constants are converted to uints in MSL.
-                        // We must ensure we write all the bytes for boolean values to work
-                        // correctly.
-                        uint32_t boolAsUint = arg ? 0x00000001 : 0x00000000;
-                        *(reinterpret_cast<uint32_t*>(buffer + PUSH_CONSTANT_SIZE_BYTES * i)) =
-                                boolAsUint;
-                    } else {
-                        *(decltype(arg)*)(buffer + PUSH_CONSTANT_SIZE_BYTES * i) = arg;
-                    }
-                },
-                constant);
-    }
-
-    switch (stage) {
-        case ShaderStage::VERTEX:
-            [(id<MTLRenderCommandEncoder>)encoder setVertexBytes:buffer
-                                                          length:bufferSize
-                                                         atIndex:PUSH_CONSTANT_BUFFER_INDEX];
-            break;
-        case ShaderStage::FRAGMENT:
-            [(id<MTLRenderCommandEncoder>)encoder setFragmentBytes:buffer
-                                                            length:bufferSize
-                                                           atIndex:PUSH_CONSTANT_BUFFER_INDEX];
-            break;
-        case ShaderStage::COMPUTE:
-            [(id<MTLComputeCommandEncoder>)encoder setBytes:buffer
-                                                     length:bufferSize
-                                                    atIndex:PUSH_CONSTANT_BUFFER_INDEX];
-            break;
-    }
-
-    mDirty = false;
-}
-
-void MetalPushConstantBuffer::clear() {
-    mPushConstants.clear();
-    mDirty = false;
-}
-
 } // namespace backend
 } // namespace filament

filament/backend/src/metal/MetalDriver.h

@@ -17,7 +17,6 @@
 #ifndef TNT_FILAMENT_DRIVER_METALDRIVER_H
 #define TNT_FILAMENT_DRIVER_METALDRIVER_H
 
-#include <backend/DriverEnums.h>
 #include "private/backend/Driver.h"
 #include "DriverBase.h"
 
@@ -32,7 +31,6 @@
 #include <functional>
 #include <mutex>
 #include <vector>
-#include <deque>
 
 namespace filament {
 namespace backend {
@@ -58,11 +56,11 @@ class MetalDriver final : public DriverBase {
 
 public:
     static Driver* create(MetalPlatform* platform, const Platform::DriverConfig& driverConfig);
+    void runAtNextTick(const std::function<void()>& fn) noexcept;
 
 private:
 
     friend class MetalSwapChain;
-    friend struct MetalDescriptorSet;
 
     MetalPlatform& mPlatform;
     MetalContext* mContext;
@@ -74,23 +72,10 @@ private:
 
     /*
      * Tasks run regularly on the driver thread.
-     * Not thread-safe; tasks are run from the driver thead and must be enqueued from the driver
-     * thread.
      */
-    void runAtNextTick(const std::function<void()>& fn) noexcept;
     void executeTickOps() noexcept;
     std::vector<std::function<void()>> mTickOps;
-
-    // Tasks regularly executed on the driver thread after a command buffer has completed
-    struct DeferredTask {
-        DeferredTask(uint64_t commandBufferId, utils::Invocable<void()>&& fn) noexcept
-            : commandBufferId(commandBufferId), fn(std::move(fn)) {}
-        uint64_t commandBufferId;     // after this command buffer completes
-        utils::Invocable<void()> fn;  // execute this task
-    };
-    void executeAfterCurrentCommandBufferCompletes(utils::Invocable<void()>&& fn) noexcept;
-    void executeDeferredOps() noexcept;
-    std::deque<DeferredTask> mDeferredTasks;
+    std::mutex mTickOpsLock;
 
     /*
      * Driver interface
@@ -151,10 +136,10 @@ private:
     inline void setRenderPrimitiveBuffer(Handle<HwRenderPrimitive> rph, PrimitiveType pt,
             Handle<HwVertexBuffer> vbh, Handle<HwIndexBuffer> ibh);
 
+    void finalizeSamplerGroup(MetalSamplerGroup* sg);
     void enumerateBoundBuffers(BufferObjectBinding bindingType,
             const std::function<void(const BufferState&, MetalBuffer*, uint32_t)>& f);
 
-    backend::StereoscopicType const mStereoscopicType;
 };
 
 } // namespace backend

filament/backend/src/metal/MetalEnums.h

@@ -71,8 +71,7 @@ constexpr inline MTLIndexType getIndexType(size_t elementSize) noexcept {
     } else if (elementSize == 4) {
         return MTLIndexTypeUInt32;
     }
-    assert_invariant(false);
-    return MTLIndexTypeUInt16;
+    ASSERT_POSTCONDITION(false, "Index element size not supported.");
 }
 
 constexpr inline MTLVertexFormat getMetalFormat(ElementType type, bool normalized) noexcept {
@@ -101,7 +100,7 @@ constexpr inline MTLVertexFormat getMetalFormat(ElementType type, bool normalize
             case ElementType::SHORT4: return MTLVertexFormatShort4Normalized;
             case ElementType::USHORT4: return MTLVertexFormatUShort4Normalized;
             default:
-                FILAMENT_CHECK_POSTCONDITION(false) << "Normalized format does not exist.";
+                ASSERT_POSTCONDITION(false, "Normalized format does not exist.");
                 return MTLVertexFormatInvalid;
         }
     }
@@ -327,8 +326,7 @@ constexpr inline MTLCullMode getMetalCullMode(CullingMode cullMode) noexcept {
         case CullingMode::FRONT: return MTLCullModeFront;
         case CullingMode::BACK: return MTLCullModeBack;
         case CullingMode::FRONT_AND_BACK:
-            FILAMENT_CHECK_POSTCONDITION(false)
-                    << "FRONT_AND_BACK culling is not supported in Metal.";
+            ASSERT_POSTCONDITION(false, "FRONT_AND_BACK culling is not supported in Metal.");
     }
 }
 

filament/backend/src/metal/MetalExternalImage.h

@@ -32,75 +32,100 @@ struct MetalContext;
  * texture.
  */
 class MetalExternalImage {
+
 public:
-    MetalExternalImage() = default;
 
-    MetalExternalImage(MetalExternalImage&&);
-    MetalExternalImage& operator=(MetalExternalImage&&);
-    ~MetalExternalImage() noexcept;
-
-    MetalExternalImage(const MetalExternalImage&) = delete;
-    MetalExternalImage& operator=(const MetalExternalImage&) = delete;
+    MetalExternalImage(MetalContext& context,
+            TextureSwizzle r = TextureSwizzle::CHANNEL_0,
+            TextureSwizzle g = TextureSwizzle::CHANNEL_1,
+            TextureSwizzle b = TextureSwizzle::CHANNEL_2,
+            TextureSwizzle a = TextureSwizzle::CHANNEL_3) noexcept;
 
     /**
-     * While the texture is used for rendering, this MetalExternalImage must be kept alive.
+     * @return true, if this MetalExternalImage is holding a live external image. Returns false
+     * until set has been called with a valid CVPixelBuffer. The image can be cleared via
+     * set(nullptr), and isValid will return false again.
      */
-    id<MTLTexture> getMtlTexture() const noexcept;
-
-    bool isValid() const noexcept {
-        return mImage != nil || mRgbTexture != nullptr;
-    }
-
-    NSUInteger getWidth() const noexcept;
-    NSUInteger getHeight() const noexcept;
+    bool isValid() const noexcept;
 
     /**
-     * Create an external image with the passed-in CVPixelBuffer.
+     * Set this external image to the passed-in CVPixelBuffer. Future calls to
+     * getMetalTextureForDraw will return a texture backed by this CVPixelBuffer. Previous
+     * CVPixelBuffers and related resources will be released when all GPU work using them has
+     * finished.
      *
-     * Ownership is taken of the CVPixelBuffer, which will be released when the returned
-     * MetalExternalImage is destroyed (or, in the case of a YCbCr image, after the conversion has
-     * completed).
-     *
-     * Calling set with a YCbCr image will encode a compute pass to convert the image from
-     * YCbCr to RGB.
+     * Calling set with a YCbCr image will encode a compute pass to convert the image from YCbCr to
+     * RGB.
      */
-    static MetalExternalImage createFromImage(MetalContext& context, CVPixelBufferRef image);
+    void set(CVPixelBufferRef image) noexcept;
 
     /**
-     * Create an external image with a specific plane of the passed-in CVPixelBuffer.
-     *
-     * Ownership is taken of the CVPixelBuffer, which will be released when the returned
-     * MetalExternalImage is destroyed.
+     * Set this external image to a specific plane of the passed-in CVPixelBuffer. Future calls to
+     * getMetalTextureForDraw will return a texture backed by a single plane of this CVPixelBuffer.
+     * Previous CVPixelBuffers and related resources will be released when all GPU work using them
+     * has finished.
      */
-    static MetalExternalImage createFromImagePlane(
-            MetalContext& context, CVPixelBufferRef image, uint32_t plane);
+    void set(CVPixelBufferRef image, size_t plane) noexcept;
 
-    static void assertWritableImage(CVPixelBufferRef image);
+    /**
+     * Returns the width of the external image, or 0 if one is not set. For YCbCr images, returns
+     * the width of the luminance plane.
+     */
+    size_t getWidth() const noexcept { return mWidth; }
+
+    /**
+     * Returns the height of the external image, or 0 if one is not set. For YCbCr images, returns
+     * the height of the luminance plane.
+     */
+    size_t getHeight() const noexcept { return mHeight; }
+
+    /**
+     * Get a Metal texture used to draw this image and denote that it is used for the current frame.
+     * For future frames that use this external image, getMetalTextureForDraw must be called again.
+     */
+    id<MTLTexture> getMetalTextureForDraw() const noexcept;
 
     /**
      * Free resources. Should be called at least once when no further calls to set will occur.
      */
     static void shutdown(MetalContext& context) noexcept;
 
-private:
-    MetalExternalImage(CVPixelBufferRef image, CVMetalTextureRef texture) noexcept
-        : mImage(image), mTexture(texture) {}
-    explicit MetalExternalImage(id<MTLTexture> texture) noexcept : mRgbTexture(texture) {}
+    static void assertWritableImage(CVPixelBufferRef image);
 
-    static id<MTLTexture> createRgbTexture(id<MTLDevice> device, size_t width, size_t height);
-    static CVMetalTextureRef createTextureFromImage(CVMetalTextureCacheRef textureCache,
-            CVPixelBufferRef image, MTLPixelFormat format, size_t plane);
-    static void ensureComputePipelineState(MetalContext& context);
-    static id<MTLCommandBuffer> encodeColorConversionPass(MetalContext& context,
-            id<MTLTexture> inYPlane, id<MTLTexture> inCbCrTexture, id<MTLTexture> outTexture);
+private:
+
+    void unset();
+
+    CVMetalTextureRef createTextureFromImage(CVPixelBufferRef image, MTLPixelFormat format,
+            size_t plane);
+    id<MTLTexture> createRgbTexture(size_t width, size_t height);
+    id<MTLTexture> createSwizzledTextureView(id<MTLTexture> texture) const;
+    id<MTLTexture> createSwizzledTextureView(CVMetalTextureRef texture) const;
+    void ensureComputePipelineState();
+    id<MTLCommandBuffer> encodeColorConversionPass(id<MTLTexture> inYPlane, id<MTLTexture>
+            inCbCrTexture, id<MTLTexture> outTexture);
 
     static constexpr size_t Y_PLANE = 0;
     static constexpr size_t CBCR_PLANE = 1;
 
-    // TODO: this could probably be a union.
+    MetalContext& mContext;
+
+    // If the external image has a single plane, mImage and mTexture hold references to the image
+    // and created Metal texture, respectively.
+    // mTextureView is a view of mTexture with any swizzling applied.
     CVPixelBufferRef mImage = nullptr;
     CVMetalTextureRef mTexture = nullptr;
+    id<MTLTexture> mTextureView = nullptr;
+    size_t mWidth = 0;
+    size_t mHeight = 0;
+
+    // If the external image is in the YCbCr format, this holds the result of the converted RGB
+    // texture.
     id<MTLTexture> mRgbTexture = nil;
+
+    struct {
+        TextureSwizzle r, g, b, a;
+    } mSwizzle;
 };
 
 } // namespace backend

filament/backend/src/metal/MetalExternalImage.mm

@@ -29,11 +29,15 @@
         auto description = [error.localizedDescription cStringUsingEncoding:NSUTF8StringEncoding]; \
         utils::slog.e << description << utils::io::endl;                                           \
     }                                                                                              \
-    FILAMENT_CHECK_POSTCONDITION(error == nil) << message;
+    ASSERT_POSTCONDITION(error == nil, message);
 
 namespace filament {
 namespace backend {
 
+static const auto cvBufferDeleter = [](const void* buffer) {
+    CVBufferRelease((CVMetalTextureRef) buffer);
+};
+
 static const char* kernel = R"(
 #include <metal_stdlib>
 #include <simd/simd.h>
@@ -67,66 +71,55 @@ ycbcrToRgb(texture2d<half, access::read>  inYTexture    [[texture(0)]],
 }
 )";
 
-NSUInteger MetalExternalImage::getWidth() const noexcept {
-    if (mImage) {
-        return CVPixelBufferGetWidth(mImage);
-    }
-    if (mRgbTexture) {
-        return mRgbTexture.width;
-    }
-    return 0;
+MetalExternalImage::MetalExternalImage(MetalContext& context, TextureSwizzle r, TextureSwizzle g,
+        TextureSwizzle b, TextureSwizzle a) noexcept : mContext(context), mSwizzle{r, g, b, a} { }
+
+bool MetalExternalImage::isValid() const noexcept {
+    return mRgbTexture != nil || mImage != nullptr;
 }
 
-NSUInteger MetalExternalImage::getHeight() const noexcept {
-    if (mImage) {
-        return CVPixelBufferGetHeight(mImage);
-    }
-    if (mRgbTexture) {
-        return mRgbTexture.height;
-    }
-    return 0;
-}
+void MetalExternalImage::set(CVPixelBufferRef image) noexcept {
+    unset();
 
-MetalExternalImage MetalExternalImage::createFromImage(
-        MetalContext& context, CVPixelBufferRef image) {
     if (!image) {
-        return {};
+        return;
     }
 
     OSType formatType = CVPixelBufferGetPixelFormatType(image);
-    FILAMENT_CHECK_POSTCONDITION(formatType == kCVPixelFormatType_32BGRA ||
-            formatType == kCVPixelFormatType_420YpCbCr8BiPlanarFullRange)
-            << "Metal external images must be in either 32BGRA or 420f format.";
+    ASSERT_POSTCONDITION(formatType == kCVPixelFormatType_32BGRA ||
+                         formatType == kCVPixelFormatType_420YpCbCr8BiPlanarFullRange,
+            "Metal external images must be in either 32BGRA or 420f format.");
 
     size_t planeCount = CVPixelBufferGetPlaneCount(image);
-    FILAMENT_CHECK_POSTCONDITION(planeCount == 0 || planeCount == 2)
-            << "The Metal backend does not support images with plane counts of " << planeCount
-            << ".";
+    ASSERT_POSTCONDITION(planeCount == 0 || planeCount == 2,
+            "The Metal backend does not support images with plane counts of %d.", planeCount);
+
 
     if (planeCount == 0) {
-        CVMetalTextureRef texture =
-                createTextureFromImage(context.textureCache, image, MTLPixelFormatBGRA8Unorm, 0);
-        return { CVPixelBufferRetain(image), texture };
+        mImage = image;
+        mTexture = createTextureFromImage(image, MTLPixelFormatBGRA8Unorm, 0);
+        mTextureView = createSwizzledTextureView(mTexture);
+        mWidth = CVPixelBufferGetWidth(image);
+        mHeight = CVPixelBufferGetHeight(image);
     }
 
     if (planeCount == 2) {
-        CVPixelBufferRetain(image);
-
-        CVMetalTextureRef yPlane =
-                createTextureFromImage(context.textureCache, image, MTLPixelFormatR8Unorm, Y_PLANE);
-        CVMetalTextureRef cbcrPlane =
-                createTextureFromImage(context.textureCache, image, MTLPixelFormatRG8Unorm, CBCR_PLANE);
+        CVMetalTextureRef yPlane = createTextureFromImage(image, MTLPixelFormatR8Unorm, Y_PLANE);
+        CVMetalTextureRef cbcrPlane = createTextureFromImage(image, MTLPixelFormatRG8Unorm,
+                CBCR_PLANE);
 
         // Get the size of luminance plane.
-        NSUInteger width = CVPixelBufferGetWidthOfPlane(image, Y_PLANE);
-        NSUInteger height = CVPixelBufferGetHeightOfPlane(image, Y_PLANE);
+        mWidth = CVPixelBufferGetWidthOfPlane(image, Y_PLANE);
+        mHeight = CVPixelBufferGetHeightOfPlane(image, Y_PLANE);
 
-        id<MTLTexture> rgbTexture = createRgbTexture(context.device, width, height);
-        id<MTLCommandBuffer> commandBuffer = encodeColorConversionPass(context,
+        id<MTLTexture> rgbTexture = createRgbTexture(mWidth, mHeight);
+        id<MTLCommandBuffer> commandBuffer = encodeColorConversionPass(
                 CVMetalTextureGetTexture(yPlane),
                 CVMetalTextureGetTexture(cbcrPlane),
                 rgbTexture);
 
+        mRgbTexture = createSwizzledTextureView(rgbTexture);
+
         [commandBuffer addCompletedHandler:^(id <MTLCommandBuffer> o) {
             CVBufferRelease(yPlane);
             CVBufferRelease(cbcrPlane);
@@ -134,85 +127,72 @@ MetalExternalImage MetalExternalImage::createFromImage(
         }];
 
         [commandBuffer commit];
-        return MetalExternalImage { rgbTexture };
     }
-
-    return {};
 }
 
-MetalExternalImage MetalExternalImage::createFromImagePlane(
-        MetalContext& context, CVPixelBufferRef image, uint32_t plane) {
+void MetalExternalImage::set(CVPixelBufferRef image, size_t plane) noexcept {
+    unset();
+
     if (!image) {
-        return {};
+        return;
     }
 
     const OSType formatType = CVPixelBufferGetPixelFormatType(image);
-    FILAMENT_CHECK_POSTCONDITION(formatType == kCVPixelFormatType_420YpCbCr8BiPlanarFullRange)
-            << "Metal planar external images must be in the 420f format.";
-    FILAMENT_CHECK_POSTCONDITION(plane == 0 || plane == 1)
-            << "Metal planar external images must be created from planes 0 or 1.";
+    ASSERT_POSTCONDITION(formatType == kCVPixelFormatType_420YpCbCr8BiPlanarFullRange,
+            "Metal planar external images must be in the 420f format.");
 
-    auto getPlaneFormat = [](size_t plane) {
-        // Right now Metal only supports kCVPixelFormatType_420YpCbCr8BiPlanarFullRange planar
-        // external images, so we can make the following assumptions about the format of each plane.
-        if (plane == 0) {
-            return MTLPixelFormatR8Unorm;  // luminance
-        }
-        if (plane == 1) {
-            return MTLPixelFormatRG8Unorm;  // CbCr
-        }
-        return MTLPixelFormatInvalid;
+    mImage = image;
+
+    auto getPlaneFormat = [] (size_t plane) {
+      // Right now Metal only supports kCVPixelFormatType_420YpCbCr8BiPlanarFullRange planar
+      // external images, so we can make the following assumptions about the format of each plane.
+      if (plane == 0) {
+        return MTLPixelFormatR8Unorm; // luminance
+      }
+      if (plane == 1) {
+        // CbCr
+        return MTLPixelFormatRG8Unorm; // CbCr
+      }
+      return MTLPixelFormatInvalid;
     };
 
     const MTLPixelFormat format = getPlaneFormat(plane);
     assert_invariant(format != MTLPixelFormatInvalid);
-    CVMetalTextureRef mTexture = createTextureFromImage(context.textureCache, image, format, plane);
-    return { CVPixelBufferRetain(image), mTexture };
+    mTexture = createTextureFromImage(image, format, plane);
+    mTextureView = createSwizzledTextureView(mTexture);
 }
 
-MetalExternalImage::MetalExternalImage(MetalExternalImage&& rhs) {
-    std::swap(mImage, rhs.mImage);
-    std::swap(mTexture, rhs.mTexture);
-    std::swap(mRgbTexture, rhs.mRgbTexture);
-}
-
-MetalExternalImage& MetalExternalImage::operator=(MetalExternalImage&& rhs) {
-    CVPixelBufferRelease(mImage);
-    CVBufferRelease(mTexture);
-    mImage = nullptr;
-    mTexture = nullptr;
-    mRgbTexture = nullptr;
-    std::swap(mImage, rhs.mImage);
-    std::swap(mTexture, rhs.mTexture);
-    std::swap(mRgbTexture, rhs.mRgbTexture);
-    return *this;
-}
-
-MetalExternalImage::~MetalExternalImage() noexcept {
-    CVPixelBufferRelease(mImage);
-    CVBufferRelease(mTexture);
-}
-
-id<MTLTexture> MetalExternalImage::getMtlTexture() const noexcept {
+id<MTLTexture> MetalExternalImage::getMetalTextureForDraw() const noexcept {
     if (mRgbTexture) {
         return mRgbTexture;
     }
-    if (mTexture) {
-        return CVMetalTextureGetTexture(mTexture);
+
+    // Retain the image and Metal texture until the GPU has finished with this frame. This does
+    // not need to be done for the RGB texture, because it is an Objective-C object whose
+    // lifetime is automatically managed by Metal.
+    auto& tracker = mContext.resourceTracker;
+    auto commandBuffer = getPendingCommandBuffer(&mContext);
+    if (tracker.trackResource((__bridge void*) commandBuffer, mImage, cvBufferDeleter)) {
+        CVPixelBufferRetain(mImage);
     }
-    return nil;
+    if (tracker.trackResource((__bridge void*) commandBuffer, mTexture, cvBufferDeleter)) {
+        CVBufferRetain(mTexture);
+    }
+
+    assert_invariant(mTextureView);
+    return mTextureView;
 }
 
-CVMetalTextureRef MetalExternalImage::createTextureFromImage(CVMetalTextureCacheRef textureCache,
-        CVPixelBufferRef image, MTLPixelFormat format, size_t plane) {
+CVMetalTextureRef MetalExternalImage::createTextureFromImage(CVPixelBufferRef image,
+        MTLPixelFormat format, size_t plane) {
     const size_t width = CVPixelBufferGetWidthOfPlane(image, plane);
     const size_t height = CVPixelBufferGetHeightOfPlane(image, plane);
 
     CVMetalTextureRef texture;
-    CVReturn result = CVMetalTextureCacheCreateTextureFromImage(kCFAllocatorDefault, textureCache,
-            image, nullptr, format, width, height, plane, &texture);
-    FILAMENT_CHECK_POSTCONDITION(result == kCVReturnSuccess)
-            << "Could not create a CVMetalTexture from CVPixelBuffer.";
+    CVReturn result = CVMetalTextureCacheCreateTextureFromImage(kCFAllocatorDefault,
+            mContext.textureCache, image, nullptr, format, width, height, plane, &texture);
+    ASSERT_POSTCONDITION(result == kCVReturnSuccess,
+            "Could not create a CVMetalTexture from CVPixelBuffer.");
 
     return texture;
 }
@@ -221,19 +201,58 @@ void MetalExternalImage::shutdown(MetalContext& context) noexcept {
     context.externalImageComputePipelineState = nil;
 }
 
-id<MTLTexture> MetalExternalImage::createRgbTexture(
-        id<MTLDevice> device, size_t width, size_t height) {
+void MetalExternalImage::assertWritableImage(CVPixelBufferRef image) {
+    OSType formatType = CVPixelBufferGetPixelFormatType(image);
+    ASSERT_PRECONDITION(formatType == kCVPixelFormatType_32BGRA,
+            "Metal SwapChain images must be in the 32BGRA format.");
+}
+
+void MetalExternalImage::unset() {
+    CVPixelBufferRelease(mImage);
+    CVBufferRelease(mTexture);
+
+    mImage = nullptr;
+    mTexture = nullptr;
+    mTextureView = nil;
+    mRgbTexture = nil;
+    mWidth = 0;
+    mHeight = 0;
+}
+
+id<MTLTexture> MetalExternalImage::createRgbTexture(size_t width, size_t height) {
     MTLTextureDescriptor *descriptor =
             [MTLTextureDescriptor texture2DDescriptorWithPixelFormat:MTLPixelFormatRGBA8Unorm
                                                                width:width
                                                               height:height
                                                            mipmapped:NO];
     descriptor.usage = MTLTextureUsageShaderWrite | MTLTextureUsageShaderRead;
-    return [device newTextureWithDescriptor:descriptor];
+    return [mContext.device newTextureWithDescriptor:descriptor];
 }
 
-void MetalExternalImage::ensureComputePipelineState(MetalContext& context) {
-    if (context.externalImageComputePipelineState != nil) {
+id<MTLTexture> MetalExternalImage::createSwizzledTextureView(id<MTLTexture> texture) const {
+    const bool isDefaultSwizzle =
+            mSwizzle.r == TextureSwizzle::CHANNEL_0 &&
+            mSwizzle.g == TextureSwizzle::CHANNEL_1 &&
+            mSwizzle.b == TextureSwizzle::CHANNEL_2 &&
+            mSwizzle.a == TextureSwizzle::CHANNEL_3;
+    if (!isDefaultSwizzle && mContext.supportsTextureSwizzling) {
+        // Even though we've already checked supportsTextureSwizzling, we still need to guard these
+        // calls with @availability, otherwise the API usage will generate compiler warnings.
+        if (@available(iOS 13, *)) {
+            texture = createTextureViewWithSwizzle(texture,
+                    getSwizzleChannels(mSwizzle.r, mSwizzle.g, mSwizzle.b, mSwizzle.a));
+        }
+    }
+    return texture;
+}
+
+id<MTLTexture> MetalExternalImage::createSwizzledTextureView(CVMetalTextureRef ref) const {
+    id<MTLTexture> texture = CVMetalTextureGetTexture(ref);
+    return createSwizzledTextureView(texture);
+}
+
+void MetalExternalImage::ensureComputePipelineState() {
+    if (mContext.externalImageComputePipelineState != nil) {
         return;
     }
 
@@ -241,28 +260,29 @@ void MetalExternalImage::ensureComputePipelineState(MetalContext& context) {
 
     NSString* objcSource = [NSString stringWithCString:kernel
                                               encoding:NSUTF8StringEncoding];
-    id<MTLLibrary> library = [context.device newLibraryWithSource:objcSource
-                                                          options:nil
-                                                            error:&error];
+    id<MTLLibrary> library = [mContext.device newLibraryWithSource:objcSource
+                                                            options:nil
+                                                              error:&error];
     NSERROR_CHECK("Unable to compile Metal shading library.");
 
     id<MTLFunction> kernelFunction = [library newFunctionWithName:@"ycbcrToRgb"];
 
-    context.externalImageComputePipelineState =
-            [context.device newComputePipelineStateWithFunction:kernelFunction error:&error];
+    mContext.externalImageComputePipelineState =
+            [mContext.device newComputePipelineStateWithFunction:kernelFunction
+                                                           error:&error];
     NSERROR_CHECK("Unable to create Metal compute pipeline state.");
 }
 
-id<MTLCommandBuffer> MetalExternalImage::encodeColorConversionPass(MetalContext& context,
-        id<MTLTexture> inYPlane, id<MTLTexture> inCbCrTexture, id<MTLTexture> outTexture) {
-    ensureComputePipelineState(context);
+id<MTLCommandBuffer> MetalExternalImage::encodeColorConversionPass(id<MTLTexture> inYPlane,
+        id<MTLTexture> inCbCrTexture, id<MTLTexture> outTexture) {
+    ensureComputePipelineState();
 
-    id<MTLCommandBuffer> commandBuffer = [context.commandQueue commandBuffer];
+    id<MTLCommandBuffer> commandBuffer = [mContext.commandQueue commandBuffer];
     commandBuffer.label = @"YCbCr to RGB conversion";
 
     id<MTLComputeCommandEncoder> computeEncoder = [commandBuffer computeCommandEncoder];
 
-    [computeEncoder setComputePipelineState:context.externalImageComputePipelineState];
+    [computeEncoder setComputePipelineState:mContext.externalImageComputePipelineState];
     [computeEncoder setTexture:inYPlane atIndex:0];
     [computeEncoder setTexture:inCbCrTexture atIndex:1];
     [computeEncoder setTexture:outTexture atIndex:2];
@@ -280,11 +300,5 @@ id<MTLCommandBuffer> MetalExternalImage::encodeColorConversionPass(MetalContext&
     return commandBuffer;
 }
 
-void MetalExternalImage::assertWritableImage(CVPixelBufferRef image) {
-    OSType formatType = CVPixelBufferGetPixelFormatType(image);
-    FILAMENT_CHECK_PRECONDITION(formatType == kCVPixelFormatType_32BGRA)
-            << "Metal SwapChain images must be in the 32BGRA format.";
-}
-
 } // namespace backend
 } // namespace filament

filament/backend/src/metal/MetalHandles.h

@@ -31,8 +31,6 @@
 
 #include "private/backend/SamplerGroup.h"
 
-#include <backend/DriverEnums.h>
-
 #include <utils/bitset.h>
 #include <utils/CString.h>
 #include <utils/FixedCapacityVector.h>
@@ -44,7 +42,6 @@
 #include <condition_variable>
 #include <memory>
 #include <type_traits>
-#include <vector>
 
 namespace filament {
 namespace backend {
@@ -74,10 +71,9 @@ public:
 
     void releaseDrawable();
 
-    void setFrameScheduledCallback(
-            CallbackHandler* handler, FrameScheduledCallback&& callback, uint64_t flags);
-    void setFrameCompletedCallback(
-            CallbackHandler* handler, utils::Invocable<void(void)>&& callback);
+    void setFrameScheduledCallback(FrameScheduledCallback callback, void* user);
+    void setFrameCompletedCallback(CallbackHandler* handler,
+            CallbackHandler::Callback callback, void* user);
 
     // For CAMetalLayer-backed SwapChains, presents the drawable or schedules a
     // FrameScheduledCallback.
@@ -86,8 +82,6 @@ public:
     NSUInteger getSurfaceWidth() const;
     NSUInteger getSurfaceHeight() const;
 
-    bool isPixelBuffer() const { return type == SwapChainType::CVPIXELBUFFERREF; }
-
 private:
 
     enum class SwapChainType {
@@ -97,6 +91,7 @@ private:
     };
     bool isCaMetalLayer() const { return type == SwapChainType::CAMETALLAYER; }
     bool isHeadless() const { return type == SwapChainType::HEADLESS; }
+    bool isPixelBuffer() const { return type == SwapChainType::CVPIXELBUFFERREF; }
 
     void scheduleFrameScheduledCallback();
     void scheduleFrameCompletedCallback();
@@ -112,40 +107,40 @@ private:
     NSUInteger headlessWidth = 0;
     NSUInteger headlessHeight = 0;
     CAMetalLayer* layer = nullptr;
-    std::shared_ptr<std::mutex> layerDrawableMutex;
     MetalExternalImage externalImage;
     SwapChainType type;
 
-    // These fields store a callback to notify the client that a frame is ready for presentation. If
-    // !frameScheduled.callback, then the Metal backend automatically calls presentDrawable when the
-    // frame is committed. Otherwise, the Metal backend will not automatically present the frame.
-    // Instead, clients bear the responsibility of presenting the frame by calling the
-    // PresentCallable object.
-    struct {
-        CallbackHandler* handler = nullptr;
-        std::shared_ptr<FrameScheduledCallback> callback = nullptr;
-        uint64_t flags = 0;
-    } frameScheduled;
+    // These two fields store a callback and user data to notify the client that a frame is ready
+    // for presentation.
+    // If frameScheduledCallback is nullptr, then the Metal backend automatically calls
+    // presentDrawable when the frame is committed.
+    // Otherwise, the Metal backend will not automatically present the frame. Instead, clients bear
+    // the responsibility of presenting the frame by calling the PresentCallable object.
+    FrameScheduledCallback frameScheduledCallback = nullptr;
+    void* frameScheduledUserData = nullptr;
 
     struct {
         CallbackHandler* handler = nullptr;
-        std::shared_ptr<utils::Invocable<void(void)>> callback = nullptr;
+        CallbackHandler::Callback callback = {};
+        void* user = nullptr;
     } frameCompleted;
 };
 
 class MetalBufferObject : public HwBufferObject {
 public:
-
-    using TagResolver = MetalBuffer::TagResolver;
-
     MetalBufferObject(MetalContext& context, BufferObjectBinding bindingType, BufferUsage usage,
          uint32_t byteCount);
 
-    void updateBuffer(void* data, size_t size, uint32_t byteOffset, TagResolver&& getHandleTag);
-    void updateBufferUnsynchronized(
-            void* data, size_t size, uint32_t byteOffset, TagResolver&& getHandleTag);
+    void updateBuffer(void* data, size_t size, uint32_t byteOffset);
+    void updateBufferUnsynchronized(void* data, size_t size, uint32_t byteOffset);
     MetalBuffer* getBuffer() { return &buffer; }
 
+    // Tracks which uniform/ssbo buffers this buffer object is bound into.
+    static_assert(Program::UNIFORM_BINDING_COUNT <= 32);
+    static_assert(MAX_SSBO_COUNT <= 32);
+    utils::bitset32 boundUniformBuffers;
+    utils::bitset32 boundSsbos;
+
 private:
     MetalBuffer buffer;
 };
@@ -202,11 +197,12 @@ public:
     MetalProgram(MetalContext& context, Program&& program) noexcept;
 
     const MetalShaderCompiler::MetalFunctionBundle& getFunctions();
-    const MetalShaderCompiler::MetalFunctionBundle& getFunctionsIfPresent() const;
+    const Program::SamplerGroupInfo& getSamplerGroupInfo() { return samplerGroupInfo; }
 
 private:
     void initialize();
 
+    Program::SamplerGroupInfo samplerGroupInfo;
     MetalContext& mContext;
     MetalShaderCompiler::MetalFunctionBundle mFunctionBundle;
     MetalShaderCompiler::program_token_t mToken;
@@ -228,42 +224,43 @@ struct PixelBufferShape {
 class MetalTexture : public HwTexture {
 public:
     MetalTexture(MetalContext& context, SamplerType target, uint8_t levels, TextureFormat format,
-            uint8_t samples, uint32_t width, uint32_t height, uint32_t depth,
-            TextureUsage usage) noexcept;
-
-    // constructors for creating texture views
-    MetalTexture(MetalContext& context, MetalTexture const* src, uint8_t baseLevel,
-            uint8_t levelCount) noexcept;
-    MetalTexture(MetalContext& context, MetalTexture const* src, TextureSwizzle r, TextureSwizzle g,
-            TextureSwizzle b, TextureSwizzle a) noexcept;
+            uint8_t samples, uint32_t width, uint32_t height, uint32_t depth, TextureUsage usage,
+            TextureSwizzle r, TextureSwizzle g, TextureSwizzle b, TextureSwizzle a)
+            noexcept;
 
     // Constructor for importing an id<MTLTexture> outside of Filament.
     MetalTexture(MetalContext& context, SamplerType target, uint8_t levels, TextureFormat format,
             uint8_t samples, uint32_t width, uint32_t height, uint32_t depth, TextureUsage usage,
             id<MTLTexture> texture) noexcept;
 
-    // Constructors for importing external images.
-    MetalTexture(MetalContext& context, TextureFormat format, uint32_t width, uint32_t height,
-            TextureUsage usage, CVPixelBufferRef image) noexcept;
-    MetalTexture(MetalContext& context, TextureFormat format, uint32_t width, uint32_t height,
-            TextureUsage usage, CVPixelBufferRef image, uint32_t plane) noexcept;
+    ~MetalTexture();
 
-    // Returns an id<MTLTexture> suitable for reading in a shader, taking into account swizzle.
-    id<MTLTexture> getMtlTextureForRead() const noexcept;
+    // Returns an id<MTLTexture> suitable for reading in a shader, taking into account swizzle and
+    // LOD clamping.
+    id<MTLTexture> getMtlTextureForRead() noexcept;
 
     // Returns the id<MTLTexture> for attaching to a render pass.
-    id<MTLTexture> getMtlTextureForWrite() const noexcept {
+    id<MTLTexture> getMtlTextureForWrite() noexcept {
         return texture;
     }
 
-    std::shared_ptr<MetalExternalImage> getExternalImage() const noexcept { return externalImage; }
-
     void loadImage(uint32_t level, MTLRegion region, PixelBufferDescriptor& p) noexcept;
     void generateMipmaps() noexcept;
 
+    // A texture starts out with none of its mip levels (also referred to as LODs) available for
+    // reading. 4 actions update the range of LODs available:
+    // - calling loadImage
+    // - calling generateMipmaps
+    // - using the texture as a render target attachment
+    // - calling setMinMaxLevels
+    // A texture's available mips are consistent throughout a render pass.
+    void setLodRange(uint16_t minLevel, uint16_t maxLevel);
+    void extendLodRangeTo(uint16_t level);
+
     static MTLPixelFormat decidePixelFormat(MetalContext* context, TextureFormat format);
 
     MetalContext& context;
+    MetalExternalImage externalImage;
 
     // A "sidecar" texture used to implement automatic MSAA resolve.
     // This is created by MetalRenderTarget and stored here so it can be used with multiple
@@ -272,6 +269,26 @@ public:
 
     MTLPixelFormat devicePixelFormat;
 
+    // Frees memory associated with this texture and marks it as "terminated".
+    // Used to track "use after free" scenario.
+    void terminate() noexcept;
+    bool isTerminated() const noexcept { return terminated; }
+    inline void checkUseAfterFree(const char* samplerGroupDebugName, size_t textureIndex) const {
+        if (UTILS_LIKELY(!isTerminated())) {
+            return;
+        }
+        NSString* reason =
+                [NSString stringWithFormat:
+                                  @"Filament Metal texture use after free, sampler group = "
+                                  @"%s, texture index = %zu",
+                          samplerGroupDebugName, textureIndex];
+        NSException* useAfterFreeException =
+                [NSException exceptionWithName:@"MetalTextureUseAfterFree"
+                                        reason:reason
+                                      userInfo:nil];
+        [useAfterFreeException raise];
+    }
+
 private:
     void loadSlice(uint32_t level, MTLRegion region, uint32_t byteOffset, uint32_t slice,
             PixelBufferDescriptor const& data) noexcept;
@@ -282,12 +299,95 @@ private:
 
     id<MTLTexture> texture = nil;
 
-    std::shared_ptr<MetalExternalImage> externalImage;
-
     // If non-nil, a swizzled texture view to use instead of "texture".
     // Filament swizzling only affects texture reads, so this should not be used when the texture is
     // bound as a render target attachment.
     id<MTLTexture> swizzledTextureView = nil;
+    id<MTLTexture> lodTextureView = nil;
+
+    uint16_t minLod = std::numeric_limits<uint16_t>::max();
+    uint16_t maxLod = 0;
+
+    bool terminated = false;
+};
+
+class MetalSamplerGroup : public HwSamplerGroup {
+public:
+    explicit MetalSamplerGroup(size_t size, utils::FixedSizeString<32> name) noexcept
+        : size(size),
+          debugName(name),
+          textureHandles(size, Handle<HwTexture>()),
+          textures(size, nil),
+          samplers(size, nil) {}
+
+    inline void setTextureHandle(size_t index, Handle<HwTexture> th) {
+        assert_invariant(!finalized);
+        textureHandles[index] = th;
+    }
+
+    // This method is only used for debugging, to ensure all texture handles are alive.
+    const auto& getTextureHandles() const {
+        return textureHandles;
+    }
+
+    // Encode a MTLTexture into this SamplerGroup at the given index.
+    inline void setFinalizedTexture(size_t index, id<MTLTexture> t) {
+        assert_invariant(!finalized);
+        textures[index] = t;
+    }
+
+    // Encode a MTLSamplerState into this SamplerGroup at the given index.
+    inline void setFinalizedSampler(size_t index, id<MTLSamplerState> s) {
+        assert_invariant(!finalized);
+        samplers[index] = s;
+    }
+
+    // A SamplerGroup is "finalized" when all of its textures have been set and is ready for use in
+    // a draw call.
+    // Once a SamplerGroup is finalized, it must be reset or mutated to be written into again.
+    void finalize();
+    bool isFinalized() const noexcept { return finalized; }
+
+    // Both of these methods "unfinalize" a SamplerGroup, allowing it to be updated via calls to
+    // setFinalizedTexture or setFinalizedSampler. The difference is that when reset is called, all
+    // the samplers/textures must be rebound. The MTLArgumentEncoder must be specified, in case
+    // the texture types have changed.
+    // Mutate re-encodes the current set of samplers/textures into the new argument
+    // buffer.
+    void reset(id<MTLCommandBuffer> cmdBuffer, id<MTLArgumentEncoder> e, id<MTLDevice> device);
+    void mutate(id<MTLCommandBuffer> cmdBuffer);
+
+    id<MTLBuffer> getArgumentBuffer() const {
+        assert_invariant(finalized);
+        return argBuffer->getCurrentAllocation().first;
+    }
+
+    NSUInteger getArgumentBufferOffset() const {
+        return argBuffer->getCurrentAllocation().second;
+    }
+
+    inline std::pair<Handle<HwTexture>, id<MTLTexture>> getFinalizedTexture(size_t index) {
+        return {textureHandles[index], textures[index]};
+    }
+
+    // Calls the Metal useResource:usage:stages: method for all the textures in this SamplerGroup.
+    void useResources(id<MTLRenderCommandEncoder> renderPassEncoder);
+
+    size_t size;
+    utils::FixedSizeString<32> debugName;
+
+public:
+
+    // These vectors are kept in sync with one another.
+    utils::FixedCapacityVector<Handle<HwTexture>> textureHandles;
+    utils::FixedCapacityVector<id<MTLTexture>> textures;
+    utils::FixedCapacityVector<id<MTLSamplerState>> samplers;
+
+    id<MTLArgumentEncoder> encoder;
+
+    std::unique_ptr<MetalRingBuffer> argBuffer = nullptr;
+
+    bool finalized = false;
 };
 
 class MetalRenderTarget : public HwRenderTarget {
@@ -438,67 +538,12 @@ struct MetalTimerQuery : public HwTimerQuery {
 
     struct Status {
         std::atomic<bool> available {false};
-        std::atomic<uint64_t> elapsed {0};   // only valid if available is true
+        uint64_t elapsed {0};   // only valid if available is true
     };
 
     std::shared_ptr<Status> status;
 };
 
-class MetalDescriptorSetLayout : public HwDescriptorSetLayout {
-public:
-    MetalDescriptorSetLayout(DescriptorSetLayout&& layout) noexcept;
-
-    const auto& getBindings() const noexcept { return mLayout.bindings; }
-
-    size_t getDynamicOffsetCount() const noexcept { return mDynamicOffsetCount; }
-
-    /**
-     * Get an argument encoder for this descriptor set and shader stage.
-     * textureTypes should only include the textures present in the corresponding shader stage.
-     */
-    id<MTLArgumentEncoder> getArgumentEncoder(id<MTLDevice> device, ShaderStage stage,
-            utils::FixedCapacityVector<MTLTextureType> const& textureTypes);
-
-private:
-    id<MTLArgumentEncoder> getArgumentEncoderSlow(id<MTLDevice> device, ShaderStage stage,
-            utils::FixedCapacityVector<MTLTextureType> const& textureTypes);
-
-    DescriptorSetLayout mLayout;
-    size_t mDynamicOffsetCount = 0;
-    std::array<id<MTLArgumentEncoder>, Program::SHADER_TYPE_COUNT> mCachedArgumentEncoder = { nil };
-    std::array<utils::FixedCapacityVector<MTLTextureType>, Program::SHADER_TYPE_COUNT>
-            mCachedTextureTypes;
-};
-
-struct MetalDescriptorSet : public HwDescriptorSet {
-    MetalDescriptorSet(MetalDescriptorSetLayout* layout) noexcept;
-
-    void finalize(MetalDriver* driver);
-
-    id<MTLBuffer> finalizeAndGetBuffer(MetalDriver* driver, ShaderStage stage);
-
-    MetalDescriptorSetLayout* layout;
-
-    struct BufferBinding {
-        id<MTLBuffer> buffer;
-        uint32_t offset;
-        uint32_t size;
-    };
-    struct TextureBinding {
-        id<MTLTexture> texture;
-        SamplerParams sampler;
-    };
-    tsl::robin_map<descriptor_binding_t, BufferBinding> buffers;
-    tsl::robin_map<descriptor_binding_t, TextureBinding> textures;
-
-    std::vector<id<MTLResource>> vertexResources;
-    std::vector<id<MTLResource>> fragmentResources;
-
-    std::vector<std::shared_ptr<MetalExternalImage>> externalImages;
-
-    std::array<TrackedMetalBuffer, Program::SHADER_TYPE_COUNT> cachedBuffer = { nil };
-};
-
 } // namespace backend
 } // namespace filament
 

filament/backend/src/metal/MetalHandles.mm

@@ -73,7 +73,7 @@ MetalSwapChain::MetalSwapChain(MetalContext& context, CAMetalLayer* nativeWindow
     : context(context),
       depthStencilFormat(decideDepthStencilFormat(flags)),
       layer(nativeWindow),
-      layerDrawableMutex(std::make_shared<std::mutex>()),
+      externalImage(context),
       type(SwapChainType::CAMETALLAYER) {
 
     if (!(flags & SwapChain::CONFIG_TRANSPARENT) && !nativeWindow.opaque) {
@@ -99,15 +99,17 @@ MetalSwapChain::MetalSwapChain(MetalContext& context, int32_t width, int32_t hei
       depthStencilFormat(decideDepthStencilFormat(flags)),
       headlessWidth(width),
       headlessHeight(height),
+      externalImage(context),
       type(SwapChainType::HEADLESS) {}
 
 MetalSwapChain::MetalSwapChain(MetalContext& context, CVPixelBufferRef pixelBuffer, uint64_t flags)
     : context(context),
       depthStencilFormat(decideDepthStencilFormat(flags)),
-      externalImage(MetalExternalImage::createFromImage(context, pixelBuffer)),
+      externalImage(context),
       type(SwapChainType::CVPIXELBUFFERREF) {
     assert_invariant(flags & SWAP_CHAIN_CONFIG_APPLE_CVPIXELBUFFER);
     MetalExternalImage::assertWritableImage(pixelBuffer);
+    externalImage.set(pixelBuffer);
     assert_invariant(externalImage.isValid());
 }
 
@@ -118,6 +120,7 @@ MTLPixelFormat MetalSwapChain::decideDepthStencilFormat(uint64_t flags) {
 }
 
 MetalSwapChain::~MetalSwapChain() {
+    externalImage.set(nullptr);
 }
 
 NSUInteger MetalSwapChain::getSurfaceWidth() const {
@@ -167,28 +170,18 @@ id<MTLTexture> MetalSwapChain::acquireDrawable() {
     }
 
     if (isPixelBuffer()) {
-        return externalImage.getMtlTexture();
+        return externalImage.getMetalTextureForDraw();
     }
 
     assert_invariant(isCaMetalLayer());
+    drawable = [layer nextDrawable];
 
-    // CAMetalLayer's drawable pool is not thread safe. Use a mutex when
-    // calling -nextDrawable, or when releasing the last known reference
-    // to any CAMetalDrawable returned from a previous -nextDrawable.
-    {
-        std::lock_guard<std::mutex> lock(*layerDrawableMutex);
-        drawable = [layer nextDrawable];
-    }
-
-    FILAMENT_CHECK_POSTCONDITION(drawable != nil) << "Could not obtain drawable.";
+    ASSERT_POSTCONDITION(drawable != nil, "Could not obtain drawable.");
     return drawable.texture;
 }
 
 void MetalSwapChain::releaseDrawable() {
-    if (drawable) {
-        std::lock_guard<std::mutex> lock(*layerDrawableMutex);
-        drawable = nil;
-    }
+    drawable = nil;
 }
 
 id<MTLTexture> MetalSwapChain::acquireDepthTexture() {
@@ -228,17 +221,16 @@ void MetalSwapChain::ensureDepthStencilTexture() {
     depthStencilTexture = [context.device newTextureWithDescriptor:descriptor];
 }
 
-void MetalSwapChain::setFrameScheduledCallback(
-        CallbackHandler* handler, FrameScheduledCallback&& callback, uint64_t flags) {
-    frameScheduled.handler = handler;
-    frameScheduled.callback = std::make_shared<FrameScheduledCallback>(std::move(callback));
-    frameScheduled.flags = flags;
+void MetalSwapChain::setFrameScheduledCallback(FrameScheduledCallback callback, void* user) {
+    frameScheduledCallback = callback;
+    frameScheduledUserData = user;
 }
 
-void MetalSwapChain::setFrameCompletedCallback(
-        CallbackHandler* handler, utils::Invocable<void(void)>&& callback) {
+void MetalSwapChain::setFrameCompletedCallback(CallbackHandler* handler,
+        CallbackHandler::Callback callback, void* user) {
     frameCompleted.handler = handler;
-    frameCompleted.callback = std::make_shared<utils::Invocable<void(void)>>(std::move(callback));
+    frameCompleted.callback = callback;
+    frameCompleted.user = user;
 }
 
 void MetalSwapChain::present() {
@@ -246,7 +238,7 @@ void MetalSwapChain::present() {
         scheduleFrameCompletedCallback();
     }
     if (drawable) {
-        if (frameScheduled.callback) {
+        if (frameScheduledCallback) {
             scheduleFrameScheduledCallback();
         } else  {
             [getPendingCommandBuffer(&context) presentDrawable:drawable];
@@ -254,17 +246,19 @@ void MetalSwapChain::present() {
     }
 }
 
+#ifndef FILAMENT_RELEASE_PRESENT_DRAWABLE_MAIN_THREAD
+#define FILAMENT_RELEASE_PRESENT_DRAWABLE_MAIN_THREAD 1
+#endif
+
 class PresentDrawableData {
 public:
     PresentDrawableData() = delete;
     PresentDrawableData(const PresentDrawableData&) = delete;
     PresentDrawableData& operator=(const PresentDrawableData&) = delete;
 
-    static PresentDrawableData* create(id<CAMetalDrawable> drawable,
-            std::shared_ptr<std::mutex> drawableMutex, MetalDriver* driver, uint64_t flags) {
-        assert_invariant(drawableMutex);
+    static PresentDrawableData* create(id<CAMetalDrawable> drawable, MetalDriver* driver) {
         assert_invariant(driver);
-        return new PresentDrawableData(drawable, drawableMutex, driver, flags);
+        return new PresentDrawableData(drawable, driver);
     }
 
     static void maybePresentAndDestroyAsync(PresentDrawableData* that, bool shouldPresent) {
@@ -272,38 +266,28 @@ public:
            [that->mDrawable present];
         }
 
-        if (that->mFlags & SwapChain::CALLBACK_DEFAULT_USE_METAL_COMPLETION_HANDLER) {
-            cleanupAndDestroy(that);
-        } else {
-            // mDrawable is acquired on the driver thread. Typically, we would release this object
-            // on the same thread, but after receiving consistent crash reports from within
-            // [CAMetalDrawable dealloc], we suspect this object requires releasing on the main
-            // thread.
-            dispatch_async(dispatch_get_main_queue(), ^{
-                cleanupAndDestroy(that);
-            });
-        }
+#if FILAMENT_RELEASE_PRESENT_DRAWABLE_MAIN_THREAD == 1
+        // mDrawable is acquired on the driver thread. Typically, we would release this object on
+        // the same thread, but after receiving consistent crash reports from within
+        // [CAMetalDrawable dealloc], we suspect this object requires releasing on the main thread.
+        dispatch_async(dispatch_get_main_queue(), ^{ cleanupAndDestroy(that); });
+#else
+        that->mDriver->runAtNextTick([that]() { cleanupAndDestroy(that); });
+#endif
     }
 
 private:
-    PresentDrawableData(id<CAMetalDrawable> drawable, std::shared_ptr<std::mutex> drawableMutex,
-            MetalDriver* driver, uint64_t flags)
-        : mDrawable(drawable), mDrawableMutex(drawableMutex), mDriver(driver), mFlags(flags) {}
+    PresentDrawableData(id<CAMetalDrawable> drawable, MetalDriver* driver)
+        : mDrawable(drawable), mDriver(driver) {}
 
     static void cleanupAndDestroy(PresentDrawableData *that) {
-        if (that->mDrawable) {
-            std::lock_guard<std::mutex> lock(*(that->mDrawableMutex));
-            that->mDrawable = nil;
-        }
-        that->mDrawableMutex.reset();
+        that->mDrawable = nil;
         that->mDriver = nullptr;
         delete that;
     }
 
     id<CAMetalDrawable> mDrawable;
-    std::shared_ptr<std::mutex> mDrawableMutex;
     MetalDriver* mDriver = nullptr;
-    uint64_t mFlags = 0;
 };
 
 void presentDrawable(bool presentFrame, void* user) {
@@ -312,43 +296,21 @@ void presentDrawable(bool presentFrame, void* user) {
 }
 
 void MetalSwapChain::scheduleFrameScheduledCallback() {
-    if (!frameScheduled.callback) {
+    if (!frameScheduledCallback) {
         return;
     }
 
     assert_invariant(drawable);
 
-    struct Callback {
-        Callback(std::shared_ptr<FrameScheduledCallback> callback, id<CAMetalDrawable> drawable,
-                 std::shared_ptr<std::mutex> drawableMutex, MetalDriver* driver, uint64_t flags)
-            : f(callback), data(PresentDrawableData::create(drawable, drawableMutex, driver, flags)) {}
-        std::shared_ptr<FrameScheduledCallback> f;
-        // PresentDrawableData* is destroyed by maybePresentAndDestroyAsync() later.
-        std::unique_ptr<PresentDrawableData> data;
-        static void func(void* user) {
-            auto* const c = reinterpret_cast<Callback*>(user);
-            PresentDrawableData* presentDrawableData = c->data.release();
-            PresentCallable presentCallable(presentDrawable, presentDrawableData);
-            c->f->operator()(presentCallable);
-            delete c;
-        }
-    };
+    // Destroy this by calling maybePresentAndDestroyAsync() later.
+    auto* presentData = PresentDrawableData::create(drawable, context.driver);
 
-    // This callback pointer will be captured by the block. Even if the scheduled handler is never
-    // called, the unique_ptr will still ensure we don't leak memory.
-    uint64_t const flags = frameScheduled.flags;
-    __block auto callback = std::make_unique<Callback>(
-            frameScheduled.callback, drawable, layerDrawableMutex, context.driver, flags);
+    FrameScheduledCallback userCallback = frameScheduledCallback;
+    void* userData = frameScheduledUserData;
 
-    backend::CallbackHandler* handler = frameScheduled.handler;
-    MetalDriver* driver = context.driver;
     [getPendingCommandBuffer(&context) addScheduledHandler:^(id<MTLCommandBuffer> cb) {
-        Callback* user = callback.release();
-        if (flags & SwapChain::CALLBACK_DEFAULT_USE_METAL_COMPLETION_HANDLER) {
-            Callback::func(user);
-        } else {
-            driver->scheduleCallback(handler, user, &Callback::func);
-        }
+        PresentCallable callable(presentDrawable, static_cast<void*>(presentData));
+        userCallback(callable, userData);
     }];
 }
 
@@ -357,25 +319,13 @@ void MetalSwapChain::scheduleFrameCompletedCallback() {
         return;
     }
 
-    struct Callback {
-        Callback(std::shared_ptr<utils::Invocable<void(void)>> callback) : f(callback) {}
-        std::shared_ptr<utils::Invocable<void(void)>> f;
-        static void func(void* user) {
-            auto* const c = reinterpret_cast<Callback*>(user);
-            c->f->operator()();
-            delete c;
-        }
-    };
-
-    // This callback pointer will be captured by the block. Even if the completed handler is never
-    // called, the unique_ptr will still ensure we don't leak memory.
-    __block auto callback = std::make_unique<Callback>(frameCompleted.callback);
-
     CallbackHandler* handler = frameCompleted.handler;
+    void* user = frameCompleted.user;
+    CallbackHandler::Callback callback = frameCompleted.callback;
+
     MetalDriver* driver = context.driver;
     [getPendingCommandBuffer(&context) addCompletedHandler:^(id<MTLCommandBuffer> cb) {
-        Callback* user = callback.release();
-        driver->scheduleCallback(handler, user, &Callback::func);
+        driver->scheduleCallback(handler, user, callback);
     }];
 }
 
@@ -383,14 +333,12 @@ MetalBufferObject::MetalBufferObject(MetalContext& context, BufferObjectBinding
         BufferUsage usage, uint32_t byteCount)
         : HwBufferObject(byteCount), buffer(context, bindingType, usage, byteCount) {}
 
-void MetalBufferObject::updateBuffer(
-        void* data, size_t size, uint32_t byteOffset, TagResolver&& getHandleTag) {
-    buffer.copyIntoBuffer(data, size, byteOffset, std::move(getHandleTag));
+void MetalBufferObject::updateBuffer(void* data, size_t size, uint32_t byteOffset) {
+    buffer.copyIntoBuffer(data, size, byteOffset);
 }
 
-void MetalBufferObject::updateBufferUnsynchronized(
-        void* data, size_t size, uint32_t byteOffset, TagResolver&& getHandleTag) {
-    buffer.copyIntoBufferUnsynchronized(data, size, byteOffset, std::move(getHandleTag));
+void MetalBufferObject::updateBufferUnsynchronized(void* data, size_t size, uint32_t byteOffset) {
+    buffer.copyIntoBufferUnsynchronized(data, size, byteOffset);
 }
 
 MetalVertexBufferInfo::MetalVertexBufferInfo(MetalContext& context, uint8_t bufferCount,
@@ -486,6 +434,11 @@ void MetalRenderPrimitive::setBuffers(MetalVertexBufferInfo const* const vbi,
 
 MetalProgram::MetalProgram(MetalContext& context, Program&& program) noexcept
     : HwProgram(program.getName()), mContext(context) {
+
+    // Save this program's SamplerGroupInfo, it's used during draw calls to bind sampler groups to
+    // the appropriate stage(s).
+    samplerGroupInfo = program.getSamplerGroupInfo();
+
     mToken = context.shaderCompiler->createProgram(program.getName(), std::move(program));
     assert_invariant(mToken);
 }
@@ -495,10 +448,6 @@ const MetalShaderCompiler::MetalFunctionBundle& MetalProgram::getFunctions() {
     return mFunctionBundle;
 }
 
-const MetalShaderCompiler::MetalFunctionBundle& MetalProgram::getFunctionsIfPresent() const {
-    return mFunctionBundle;
-}
-
 void MetalProgram::initialize() {
     if (!mToken) {
         return;
@@ -509,21 +458,21 @@ void MetalProgram::initialize() {
 
 MetalTexture::MetalTexture(MetalContext& context, SamplerType target, uint8_t levels,
         TextureFormat format, uint8_t samples, uint32_t width, uint32_t height, uint32_t depth,
-        TextureUsage usage) noexcept
-    : HwTexture(target, levels, samples, width, height, depth, format, usage), context(context) {
-    assert_invariant(target != SamplerType::SAMPLER_EXTERNAL);
+        TextureUsage usage, TextureSwizzle r, TextureSwizzle g, TextureSwizzle b,
+        TextureSwizzle a) noexcept
+    : HwTexture(target, levels, samples, width, height, depth, format, usage), context(context),
+        externalImage(context, r, g, b, a) {
 
     devicePixelFormat = decidePixelFormat(&context, format);
-    FILAMENT_CHECK_POSTCONDITION(devicePixelFormat != MTLPixelFormatInvalid)
-            << "Texture format not supported.";
+    ASSERT_POSTCONDITION(devicePixelFormat != MTLPixelFormatInvalid, "Texture format not supported.");
 
     const BOOL mipmapped = levels > 1;
     const BOOL multisampled = samples > 1;
 
 #if defined(IOS)
     const BOOL textureArray = target == SamplerType::SAMPLER_2D_ARRAY;
-    FILAMENT_CHECK_PRECONDITION(!textureArray || !multisampled)
-            << "iOS does not support multisampled texture arrays.";
+    ASSERT_PRECONDITION(!textureArray || !multisampled,
+            "iOS does not support multisampled texture arrays.");
 #endif
 
     const auto get2DTextureType = [](SamplerType target, bool isMultisampled) {
@@ -558,12 +507,12 @@ MetalTexture::MetalTexture(MetalContext& context, SamplerType target, uint8_t le
             descriptor.usage = getMetalTextureUsage(usage);
             descriptor.storageMode = MTLStorageModePrivate;
             texture = [context.device newTextureWithDescriptor:descriptor];
+            ASSERT_POSTCONDITION(texture != nil, "Could not create Metal texture. Out of memory?");
             break;
         case SamplerType::SAMPLER_CUBEMAP:
         case SamplerType::SAMPLER_CUBEMAP_ARRAY:
-            FILAMENT_CHECK_POSTCONDITION(!multisampled)
-                    << "Multisampled cubemap faces not supported.";
-            FILAMENT_CHECK_POSTCONDITION(width == height) << "Cubemap faces must be square.";
+            ASSERT_POSTCONDITION(!multisampled, "Multisampled cubemap faces not supported.");
+            ASSERT_POSTCONDITION(width == height, "Cubemap faces must be square.");
             descriptor = [MTLTextureDescriptor textureCubeDescriptorWithPixelFormat:devicePixelFormat
                                                                                size:width
                                                                           mipmapped:mipmapped];
@@ -572,6 +521,7 @@ MetalTexture::MetalTexture(MetalContext& context, SamplerType target, uint8_t le
             descriptor.usage = getMetalTextureUsage(usage);
             descriptor.storageMode = MTLStorageModePrivate;
             texture = [context.device newTextureWithDescriptor:descriptor];
+            ASSERT_POSTCONDITION(texture != nil, "Could not create Metal texture. Out of memory?");
             break;
         case SamplerType::SAMPLER_3D:
             descriptor = [MTLTextureDescriptor new];
@@ -584,6 +534,7 @@ MetalTexture::MetalTexture(MetalContext& context, SamplerType target, uint8_t le
             descriptor.usage = getMetalTextureUsage(usage);
             descriptor.storageMode = MTLStorageModePrivate;
             texture = [context.device newTextureWithDescriptor:descriptor];
+            ASSERT_POSTCONDITION(texture != nil, "Could not create Metal texture. Out of memory?");
             break;
         case SamplerType::SAMPLER_EXTERNAL:
             // If we're using external textures (CVPixelBufferRefs), we don't need to make any
@@ -592,33 +543,15 @@ MetalTexture::MetalTexture(MetalContext& context, SamplerType target, uint8_t le
             break;
     }
 
-    FILAMENT_CHECK_POSTCONDITION(target == SamplerType::SAMPLER_EXTERNAL || texture != nil)
-            << "Could not create Metal texture (SamplerType = " << int(target)
-            << ", levels = " << int(levels) << ", MTLPixelFormat = " << int(devicePixelFormat)
-            << ", width = " << width << ", height = " << height << ", depth = " << depth
-            << "). Out of memory?";
-}
-
-MetalTexture::MetalTexture(MetalContext& context, MetalTexture const* src, uint8_t baseLevel,
-        uint8_t levelCount) noexcept
-    : HwTexture(src->target, src->levels, src->samples, src->width, src->height, src->depth,
-              src->format, src->usage),
-      context(context),
-      devicePixelFormat(src->devicePixelFormat),
-      externalImage(src->externalImage) {
-    texture = createTextureViewWithLodRange(
-            src->getMtlTextureForRead(), baseLevel, baseLevel + levelCount - 1);
-}
-
-MetalTexture::MetalTexture(MetalContext& context, MetalTexture const* src, TextureSwizzle r,
-        TextureSwizzle g, TextureSwizzle b, TextureSwizzle a) noexcept
-    : HwTexture(src->target, src->levels, src->samples, src->width, src->height, src->depth,
-              src->format, src->usage),
-      context(context),
-      devicePixelFormat(src->devicePixelFormat),
-      externalImage(src->externalImage) {
-    texture = src->getMtlTextureForRead();
-    if (context.supportsTextureSwizzling) {
+    // If swizzling is set, set up a swizzled texture view that we'll use when sampling this texture.
+    const bool isDefaultSwizzle =
+            r == TextureSwizzle::CHANNEL_0 &&
+            g == TextureSwizzle::CHANNEL_1 &&
+            b == TextureSwizzle::CHANNEL_2 &&
+            a == TextureSwizzle::CHANNEL_3;
+    // If texture is nil, then it must be a SAMPLER_EXTERNAL texture.
+    // Swizzling for external textures is handled inside MetalExternalImage.
+    if (!isDefaultSwizzle && texture && context.supportsTextureSwizzling) {
         // Even though we've already checked context.supportsTextureSwizzling, we still need to
         // guard these calls with @availability, otherwise the API usage will generate compiler
         // warnings.
@@ -632,30 +565,44 @@ MetalTexture::MetalTexture(MetalContext& context, MetalTexture const* src, Textu
 MetalTexture::MetalTexture(MetalContext& context, SamplerType target, uint8_t levels, TextureFormat format,
         uint8_t samples, uint32_t width, uint32_t height, uint32_t depth, TextureUsage usage,
         id<MTLTexture> metalTexture) noexcept
-    : HwTexture(target, levels, samples, width, height, depth, format, usage), context(context) {
+    : HwTexture(target, levels, samples, width, height, depth, format, usage), context(context),
+        externalImage(context) {
     texture = metalTexture;
+    setLodRange(0, levels - 1);
 }
 
-MetalTexture::MetalTexture(MetalContext& context, TextureFormat format, uint32_t width,
-        uint32_t height, TextureUsage usage, CVPixelBufferRef image) noexcept
-    : HwTexture(SamplerType::SAMPLER_EXTERNAL, 1, 1, width, height, 1, format, usage),
-      context(context),
-      externalImage(std::make_shared<MetalExternalImage>(
-              MetalExternalImage::createFromImage(context, image))) {
-    texture = externalImage->getMtlTexture();
+void MetalTexture::terminate() noexcept {
+    texture = nil;
+    swizzledTextureView = nil;
+    lodTextureView = nil;
+    msaaSidecar = nil;
+    externalImage.set(nullptr);
+    terminated = true;
 }
 
-MetalTexture::MetalTexture(MetalContext& context, TextureFormat format, uint32_t width,
-        uint32_t height, TextureUsage usage, CVPixelBufferRef image, uint32_t plane) noexcept
-    : HwTexture(SamplerType::SAMPLER_EXTERNAL, 1, 1, width, height, 1, format, usage),
-      context(context),
-      externalImage(std::make_shared<MetalExternalImage>(
-              MetalExternalImage::createFromImagePlane(context, image, plane))) {
-    texture = externalImage->getMtlTexture();
+MetalTexture::~MetalTexture() {
+    externalImage.set(nullptr);
 }
 
-id<MTLTexture> MetalTexture::getMtlTextureForRead() const noexcept {
-    return swizzledTextureView ? swizzledTextureView : texture;
+id<MTLTexture> MetalTexture::getMtlTextureForRead() noexcept {
+    if (lodTextureView) {
+        return lodTextureView;
+    }
+    // The texture's swizzle remains constant throughout its lifetime, however its LOD range can
+    // change. We'll cache the LOD view, and set lodTextureView to nil if minLod or maxLod is
+    // updated.
+    id<MTLTexture> t = swizzledTextureView ? swizzledTextureView : texture;
+    if (!t) {
+        return nil;
+    }
+    if (UTILS_UNLIKELY(minLod > maxLod)) {
+        // If the texture does not have any available LODs, provide a view of only level 0.
+        // Filament should prevent this from ever occurring.
+        lodTextureView = createTextureViewWithLodRange(t, 0, 0);
+        return lodTextureView;
+    }
+    lodTextureView = createTextureViewWithLodRange(t, minLod, maxLod);
+    return lodTextureView;
 }
 
 MTLPixelFormat MetalTexture::decidePixelFormat(MetalContext* context, TextureFormat format) {
@@ -774,21 +721,24 @@ void MetalTexture::loadImage(uint32_t level, MTLRegion region, PixelBufferDescri
             assert_invariant(false);
         }
     }
+
+    extendLodRangeTo(level);
 }
 
 void MetalTexture::generateMipmaps() noexcept {
     id <MTLBlitCommandEncoder> blitEncoder = [getPendingCommandBuffer(&context) blitCommandEncoder];
     [blitEncoder generateMipmapsForTexture:texture];
     [blitEncoder endEncoding];
+    setLodRange(0, texture.mipmapLevelCount - 1);
 }
 
 void MetalTexture::loadSlice(uint32_t level, MTLRegion region, uint32_t byteOffset, uint32_t slice,
         PixelBufferDescriptor const& data) noexcept {
     const PixelBufferShape shape = PixelBufferShape::compute(data, format, region.size, byteOffset);
 
-    FILAMENT_CHECK_PRECONDITION(data.size >= shape.totalBytes)
-            << "Expected buffer size of at least " << shape.totalBytes
-            << " but received PixelBufferDescriptor with size " << data.size << ".";
+    ASSERT_PRECONDITION(data.size >= shape.totalBytes,
+            "Expected buffer size of at least %d but "
+            "received PixelBufferDescriptor with size %d.", shape.totalBytes, data.size);
 
     // Earlier versions of iOS don't have the maxBufferLength query, but 256 MB is a safe bet.
     NSUInteger deviceMaxBufferLength = 256 * 1024 * 1024;   // 256 MB
@@ -903,6 +853,98 @@ void MetalTexture::loadWithBlit(uint32_t level, uint32_t slice, MTLRegion region
     context.blitter->blit(getPendingCommandBuffer(&context), args, "Texture upload blit");
 }
 
+void MetalTexture::extendLodRangeTo(uint16_t level) {
+    assert_invariant(!isInRenderPass(&context));
+    minLod = std::min(minLod, level);
+    maxLod = std::max(maxLod, level);
+    lodTextureView = nil;
+}
+
+void MetalTexture::setLodRange(uint16_t min, uint16_t max) {
+    assert_invariant(!isInRenderPass(&context));
+    assert_invariant(min <= max);
+    minLod = min;
+    maxLod = max;
+    lodTextureView = nil;
+}
+
+void MetalSamplerGroup::finalize() {
+    assert_invariant(encoder);
+    // TODO: we should be able to encode textures and samplers inside setFinalizedTexture and
+    // setFinalizedSampler as they become available, but Metal doesn't seem to like this; the arg
+    // buffer gets encoded incorrectly. This warrants more investigation.
+
+    auto [buffer, offset] = argBuffer->getCurrentAllocation();
+    [encoder setArgumentBuffer:buffer offset:offset];
+
+    // Encode all textures and samplers.
+    for (size_t s = 0; s < size; s++) {
+        [encoder setTexture:textures[s] atIndex:(s * 2 + 0)];
+        [encoder setSamplerState:samplers[s] atIndex:(s * 2 + 1)];
+    }
+
+    finalized = true;
+}
+
+void MetalSamplerGroup::reset(id<MTLCommandBuffer> cmdBuffer, id<MTLArgumentEncoder> e,
+        id<MTLDevice> device) {
+    encoder = e;
+
+    // The number of slots in the ring buffer we use to manage argument buffer allocations.
+    // This number was chosen to avoid running out of slots and having to allocate a "fallback"
+    // buffer when SamplerGroups are updated multiple times a frame. This value can reduced after
+    // auditing Filament's calls to updateSamplerGroup, which should be as few times as possible.
+    // For example, the bloom downsample pass should be refactored to maintain two separate
+    // MaterialInstances instead of "ping ponging" between two texture bindings, which causes a
+    // single SamplerGroup to be updated many times a frame.
+    static constexpr auto METAL_ARGUMENT_BUFFER_SLOTS = 32;
+
+    MTLSizeAndAlign argBufferLayout;
+    argBufferLayout.size = encoder.encodedLength;
+    argBufferLayout.align = encoder.alignment;
+    // Chances are, even though the MTLArgumentEncoder might change, the required size and alignment
+    // probably won't. So we can re-use the previous ring buffer.
+    if (UTILS_UNLIKELY(!argBuffer || !argBuffer->canAccomodateLayout(argBufferLayout))) {
+        argBuffer = std::make_unique<MetalRingBuffer>(device, MTLResourceStorageModeShared,
+                argBufferLayout, METAL_ARGUMENT_BUFFER_SLOTS);
+    } else {
+        argBuffer->createNewAllocation(cmdBuffer);
+    }
+
+    // Clear all textures and samplers.
+    assert_invariant(textureHandles.size() == textures.size());
+    assert_invariant(textures.size() == samplers.size());
+    for (size_t s = 0; s < textureHandles.size(); s++) {
+        textureHandles[s] = {};
+        textures[s] = nil;
+        samplers[s] = nil;
+    }
+
+    finalized = false;
+}
+
+void MetalSamplerGroup::mutate(id<MTLCommandBuffer> cmdBuffer) {
+    assert_invariant(finalized);    // only makes sense to mutate if this sampler group is finalized
+    assert_invariant(argBuffer);
+    argBuffer->createNewAllocation(cmdBuffer);
+    finalized = false;
+}
+
+void MetalSamplerGroup::useResources(id<MTLRenderCommandEncoder> renderPassEncoder) {
+    assert_invariant(finalized);
+    if (@available(iOS 13, *)) {
+        // TODO: pass only the appropriate stages to useResources.
+        [renderPassEncoder useResources:textures.data()
+                                  count:textures.size()
+                                  usage:MTLResourceUsageRead | MTLResourceUsageSample
+                                 stages:MTLRenderStageFragment | MTLRenderStageVertex];
+    } else {
+        [renderPassEncoder useResources:textures.data()
+                                  count:textures.size()
+                                  usage:MTLResourceUsageRead | MTLResourceUsageSample];
+    }
+}
+
 MetalRenderTarget::MetalRenderTarget(MetalContext* context, uint32_t width, uint32_t height,
         uint8_t samples, Attachment colorAttachments[MRT::MAX_SUPPORTED_RENDER_TARGET_COUNT],
         Attachment depthAttachment, Attachment stencilAttachment) :
@@ -917,9 +959,9 @@ MetalRenderTarget::MetalRenderTarget(MetalContext* context, uint32_t width, uint
         }
         color[i] = colorAttachments[i];
 
-        FILAMENT_CHECK_PRECONDITION(color[i].getSampleCount() <= samples)
-                << "MetalRenderTarget was initialized with a MSAA COLOR" << i
-                << " texture, but sample count is " << samples << ".";
+        ASSERT_PRECONDITION(color[i].getSampleCount() <= samples,
+                "MetalRenderTarget was initialized with a MSAA COLOR%d texture, but sample count is %d.",
+                i, samples);
 
         auto t = color[i].metalTexture;
         const auto twidth = std::max(1u, t->width >> color[i].level);
@@ -942,10 +984,9 @@ MetalRenderTarget::MetalRenderTarget(MetalContext* context, uint32_t width, uint
     if (depthAttachment) {
         depth = depthAttachment;
 
-        FILAMENT_CHECK_PRECONDITION(depth.getSampleCount() <= samples)
-                << "MetalRenderTarget was initialized with a MSAA DEPTH texture, but sample count "
-                   "is "
-                << samples << ".";
+        ASSERT_PRECONDITION(depth.getSampleCount() <= samples,
+                "MetalRenderTarget was initialized with a MSAA DEPTH texture, but sample count is %d.",
+                samples);
 
         auto t = depth.metalTexture;
         const auto twidth = std::max(1u, t->width >> depth.level);
@@ -968,10 +1009,9 @@ MetalRenderTarget::MetalRenderTarget(MetalContext* context, uint32_t width, uint
     if (stencilAttachment) {
         stencil = stencilAttachment;
 
-        FILAMENT_CHECK_PRECONDITION(stencil.getSampleCount() <= samples)
-                << "MetalRenderTarget was initialized with a MSAA STENCIL texture, but sample "
-                   "count is "
-                << samples << ".";
+        ASSERT_PRECONDITION(stencil.getSampleCount() <= samples,
+                "MetalRenderTarget was initialized with a MSAA STENCIL texture, but sample count is %d.",
+                samples);
 
         auto t = stencil.metalTexture;
         const auto twidth = std::max(1u, t->width >> stencil.level);
@@ -1248,195 +1288,5 @@ FenceStatus MetalFence::wait(uint64_t timeoutNs) {
     return FenceStatus::ERROR;
 }
 
-MetalDescriptorSetLayout::MetalDescriptorSetLayout(DescriptorSetLayout&& l) noexcept
-    : mLayout(std::move(l)) {
-    size_t dynamicBindings = 0;
-    for (const auto& binding : mLayout.bindings) {
-        if (any(binding.flags & DescriptorFlags::DYNAMIC_OFFSET)) {
-            dynamicBindings++;
-        }
-    }
-    mDynamicOffsetCount = dynamicBindings;
-}
-
-id<MTLArgumentEncoder> MetalDescriptorSetLayout::getArgumentEncoder(id<MTLDevice> device, ShaderStage stage,
-        utils::FixedCapacityVector<MTLTextureType> const& textureTypes) {
-    auto const index = static_cast<size_t>(stage);
-    assert_invariant(index < mCachedArgumentEncoder.size());
-    if (mCachedArgumentEncoder[index] &&
-            std::equal(
-                    textureTypes.begin(), textureTypes.end(), mCachedTextureTypes[index].begin())) {
-        return mCachedArgumentEncoder[index];
-    }
-    mCachedArgumentEncoder[index] = getArgumentEncoderSlow(device, stage, textureTypes);
-    mCachedTextureTypes[index] = textureTypes;
-    return mCachedArgumentEncoder[index];
-}
-
-id<MTLArgumentEncoder> MetalDescriptorSetLayout::getArgumentEncoderSlow(id<MTLDevice> device,
-        ShaderStage stage, utils::FixedCapacityVector<MTLTextureType> const& textureTypes) {
-    auto const& bindings = getBindings();
-    NSMutableArray<MTLArgumentDescriptor*>* arguments = [NSMutableArray new];
-    // Important! The bindings must be sorted by binding number. This has already been done inside
-    // createDescriptorSetLayout.
-    size_t textureIndex = 0;
-    for (auto const& binding : bindings) {
-        if (!hasShaderType(binding.stageFlags, stage)) {
-            continue;
-        }
-        switch (binding.type) {
-            case DescriptorType::UNIFORM_BUFFER:
-            case DescriptorType::SHADER_STORAGE_BUFFER: {
-                MTLArgumentDescriptor* bufferArgument = [MTLArgumentDescriptor argumentDescriptor];
-                bufferArgument.index = binding.binding * 2;
-                bufferArgument.dataType = MTLDataTypePointer;
-                bufferArgument.access = MTLArgumentAccessReadOnly;
-                [arguments addObject:bufferArgument];
-                break;
-            }
-            case DescriptorType::SAMPLER:
-            case DescriptorType::SAMPLER_EXTERNAL: {
-                MTLArgumentDescriptor* textureArgument = [MTLArgumentDescriptor argumentDescriptor];
-                textureArgument.index = binding.binding * 2;
-                textureArgument.dataType = MTLDataTypeTexture;
-                MTLTextureType textureType = MTLTextureType2D;
-                if (textureIndex < textureTypes.size()) {
-                    textureType = textureTypes[textureIndex++];
-                }
-                textureArgument.textureType = textureType;
-                textureArgument.access = MTLArgumentAccessReadOnly;
-                [arguments addObject:textureArgument];
-
-                MTLArgumentDescriptor* samplerArgument = [MTLArgumentDescriptor argumentDescriptor];
-                samplerArgument.index = binding.binding * 2 + 1;
-                samplerArgument.dataType = MTLDataTypeSampler;
-                textureArgument.access = MTLArgumentAccessReadOnly;
-                [arguments addObject:samplerArgument];
-                break;
-            }
-            case DescriptorType::INPUT_ATTACHMENT:
-                // TODO: support INPUT_ATTACHMENT
-                assert_invariant(false);
-                break;
-        }
-    }
-    return [device newArgumentEncoderWithArguments:arguments];
-}
-
-MetalDescriptorSet::MetalDescriptorSet(MetalDescriptorSetLayout* layout) noexcept
-    : layout(layout) {}
-
-void MetalDescriptorSet::finalize(MetalDriver* driver) {
-    [driver->mContext->currentRenderPassEncoder useResource:driver->mContext->emptyBuffer
-                                                      usage:MTLResourceUsageRead];
-    [driver->mContext->currentRenderPassEncoder
-            useResource:getOrCreateEmptyTexture(driver->mContext)
-                  usage:MTLResourceUsageRead];
-
-    if (@available(iOS 13.0, *)) {
-        [driver->mContext->currentRenderPassEncoder useResources:vertexResources.data()
-                                                           count:vertexResources.size()
-                                                           usage:MTLResourceUsageRead
-                                                          stages:MTLRenderStageVertex];
-        [driver->mContext->currentRenderPassEncoder useResources:fragmentResources.data()
-                                                           count:fragmentResources.size()
-                                                           usage:MTLResourceUsageRead
-                                                          stages:MTLRenderStageFragment];
-    } else {
-        [driver->mContext->currentRenderPassEncoder useResources:vertexResources.data()
-                                                           count:vertexResources.size()
-                                                           usage:MTLResourceUsageRead];
-        [driver->mContext->currentRenderPassEncoder useResources:fragmentResources.data()
-                                                           count:fragmentResources.size()
-                                                           usage:MTLResourceUsageRead];
-    }
-}
-
-id<MTLBuffer> MetalDescriptorSet::finalizeAndGetBuffer(MetalDriver* driver, ShaderStage stage) {
-    auto const index = static_cast<size_t>(stage);
-    assert_invariant(index < cachedBuffer.size());
-    auto& buffer = cachedBuffer[index];
-
-    if (buffer) {
-        return buffer.get();
-    }
-
-    // Map all the texture bindings to their respective texture types.
-    auto const& bindings = layout->getBindings();
-    auto textureTypes = utils::FixedCapacityVector<MTLTextureType>::with_capacity(bindings.size());
-    for (auto const& binding : bindings) {
-        if (!hasShaderType(binding.stageFlags, stage)) {
-            continue;
-        }
-        MTLTextureType textureType = MTLTextureType2D;
-        if (auto found = textures.find(binding.binding); found != textures.end()) {
-            auto const& textureBinding = textures[binding.binding];
-            textureType = textureBinding.texture.textureType;
-        }
-        textureTypes.push_back(textureType);
-    }
-
-    MetalContext const& context = *driver->mContext;
-
-    id<MTLArgumentEncoder> encoder =
-            layout->getArgumentEncoder(context.device, stage, textureTypes);
-
-    {
-        ScopedAllocationTimer timer("descriptor_set");
-        buffer = { [context.device newBufferWithLength:encoder.encodedLength
-                                               options:MTLResourceStorageModeShared],
-            TrackedMetalBuffer::Type::DESCRIPTOR_SET };
-    }
-    [encoder setArgumentBuffer:buffer.get() offset:0];
-
-    for (auto const& binding : bindings) {
-        if (!hasShaderType(binding.stageFlags, stage)) {
-            continue;
-        }
-        switch (binding.type) {
-            case DescriptorType::UNIFORM_BUFFER:
-            case DescriptorType::SHADER_STORAGE_BUFFER: {
-                auto found = buffers.find(binding.binding);
-                if (found == buffers.end()) {
-                    [encoder setBuffer:driver->mContext->emptyBuffer
-                                offset:0
-                               atIndex:binding.binding * 2];
-                    continue;
-                }
-
-                auto const& bufferBinding = buffers[binding.binding];
-                [encoder setBuffer:bufferBinding.buffer
-                            offset:bufferBinding.offset
-                           atIndex:binding.binding * 2];
-                break;
-            }
-            case DescriptorType::SAMPLER:
-            case DescriptorType::SAMPLER_EXTERNAL: {
-                auto found = textures.find(binding.binding);
-                if (found == textures.end()) {
-                    [encoder setTexture:driver->mContext->emptyTexture atIndex:binding.binding * 2];
-                    id<MTLSamplerState> sampler =
-                            driver->mContext->samplerStateCache.getOrCreateState({});
-                    [encoder setSamplerState:sampler atIndex:binding.binding * 2 + 1];
-                    continue;
-                }
-
-                auto const& textureBinding = textures[binding.binding];
-                [encoder setTexture:textureBinding.texture atIndex:binding.binding * 2];
-                SamplerState samplerState { .samplerParams = textureBinding.sampler };
-                id<MTLSamplerState> sampler =
-                        driver->mContext->samplerStateCache.getOrCreateState(samplerState);
-                [encoder setSamplerState:sampler atIndex:binding.binding * 2 + 1];
-                break;
-            }
-            case DescriptorType::INPUT_ATTACHMENT:
-                assert_invariant(false);
-                break;
-        }
-    }
-
-    return buffer.get();
-}
-
 } // namespace backend
 } // namespace filament

filament/backend/src/metal/MetalShaderCompiler.h

@@ -83,10 +83,6 @@ public:
             return std::get<Compute>(mPrograms);
         }
 
-        bool isRaster() const { return std::holds_alternative<Raster>(mPrograms); }
-
-        bool isCompute() const { return std::holds_alternative<Compute>(mPrograms); }
-
         static MetalFunctionBundle none() {
             return MetalFunctionBundle(None{});
         }

filament/backend/src/metal/MetalShaderCompiler.mm

@@ -106,41 +106,26 @@ bool MetalShaderCompiler::isParallelShaderCompileSupported() const noexcept {
             continue;
         }
 
+        assert_invariant(source[source.size() - 1] == '\0');
+
+        // the shader string is null terminated and the length includes the null character
+        NSString* objcSource = [[NSString alloc] initWithBytes:source.data()
+                                                        length:source.size() - 1
+                                                      encoding:NSUTF8StringEncoding];
+
+        // By default, Metal uses the most recent language version.
+        MTLCompileOptions* options = [MTLCompileOptions new];
+
+        // Disable Fast Math optimizations.
+        // This ensures that operations adhere to IEEE standards for floating-point arithmetic,
+        // which is crucial for half precision floats in scenarios where fast math optimizations
+        // lead to inaccuracies, such as in handling special values like NaN or Infinity.
+        options.fastMathEnabled = NO;
+
         NSError* error = nil;
-        id<MTLLibrary> library = nil;
-        switch (program.getShaderLanguage()) {
-            case ShaderLanguage::MSL: {
-                // By default, Metal uses the most recent language version.
-                MTLCompileOptions* options = [MTLCompileOptions new];
-
-                // Disable Fast Math optimizations.
-                // This ensures that operations adhere to IEEE standards for floating-point
-                // arithmetic, which is crucial for half precision floats in scenarios where fast
-                // math optimizations lead to inaccuracies, such as in handling special values like
-                // NaN or Infinity.
-                options.fastMathEnabled = NO;
-
-                assert_invariant(source[source.size() - 1] == '\0');
-                // the shader string is null terminated and the length includes the null character
-                NSString* objcSource = [[NSString alloc] initWithBytes:source.data()
-                                                                length:source.size() - 1
-                                                              encoding:NSUTF8StringEncoding];
-                library = [device newLibraryWithSource:objcSource options:options error:&error];
-                break;
-            }
-            case ShaderLanguage::METAL_LIBRARY: {
-                dispatch_data_t data = dispatch_data_create(source.data(), source.size(),
-                        dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0),
-                        DISPATCH_DATA_DESTRUCTOR_DEFAULT);
-                library = [device newLibraryWithData:data error:&error];
-                break;
-            }
-            case ShaderLanguage::ESSL1:
-            case ShaderLanguage::ESSL3:
-            case ShaderLanguage::SPIRV:
-                break;
-        }
-
+        id<MTLLibrary> library = [device newLibraryWithSource:objcSource
+                                                      options:options
+                                                        error:&error];
         if (library == nil) {
             NSString* errorMessage = @"unknown error";
             if (error) {
@@ -169,23 +154,6 @@ bool MetalShaderCompiler::isParallelShaderCompileSupported() const noexcept {
         id<MTLFunction> function = [library newFunctionWithName:@"main0"
                                                  constantValues:constants
                                                           error:&error];
-        if (function == nil) {
-            // If the library loads but functions within it fail to load, it usually means the
-            // GPU backend crashed. (This can happen if it's a Metallib shader that was compiled
-            // with a minimum iOS version that's newer than this device.)
-            NSString* errorMessage = @"unknown error";
-            if (error) {
-                auto description =
-                        [error.localizedDescription cStringUsingEncoding:NSUTF8StringEncoding];
-                utils::slog.w << description << utils::io::endl;
-                errorMessage = error.localizedDescription;
-            }
-            PANIC_LOG("Failed to load main0 in Metal program.");
-            NSString* programName =
-                [NSString stringWithFormat:@"%s::main0", program.getName().c_str_safe()];
-            return MetalFunctionBundle::error(errorMessage, programName);
-        }
-
         if (!program.getName().empty()) {
             function.label = @(program.getName().c_str());
         }