Use MapAsync and AllowProcessEvents for callback

This allows for static call from java, e.g.:

```
static {
    Utils.init();
}
```

.clang-format

@@ -65,4 +65,6 @@ SpacesInParentheses: false
 SpacesInSquareBrackets: false
 TabWidth: 4
 UseTab: Never
-PackConstructorInitializers: Never
+PackConstructorInitializers: Never
+ConstructorInitializerIndentWidth: 8
+IndentWrappedFunctionNames: true

.github/actions/get-commit-msg/action.yml

@@ -1,43 +1,53 @@
+# This action retrieves the latest commit message from a push or pull_request event
+# and makes it available as an output variable named 'msg'.
 name: 'Get commit message'
 outputs:
   msg:
     value: ${{ steps.action_output.outputs.msg }}
+  hash:
+    value: ${{ steps.action_output.outputs.hash }}
 runs:
   using: "composite"
   steps:
     - name: Find commit message (on push)
       if: github.event_name == 'push'
       shell: bash
+      env:
+        COMMIT_MESSAGE: ${{ github.event.head_commit.message }}
       run: |
         AUTHOR_NAME="${{ github.event.head_commit.author.name }}"
         AUTHOR_EMAIL="${{ github.event.head_commit.author.email }}"
         TSTAMP="${{ github.event.head_commit.timestamp }}"
-        echo "commit ${{ github.event.head_commit.id }}" >> /tmp/commit_msg.txt
+        HASH="${{ github.event.head_commit.id }}"
+        echo "commit $HASH" >> /tmp/commit_msg.txt
         echo "Author: ${AUTHOR_NAME}<${AUTHOR_EMAIL}>" >> /tmp/commit_msg.txt
         echo "Date: ${TSTAMP}" >> /tmp/commit_msg.txt
         echo "" >> /tmp/commit_msg.txt
-        echo "${{ github.event.head_commit.message }}" >> /tmp/commit_msg.txt
+        echo "$COMMIT_MESSAGE" >> /tmp/commit_msg.txt
+        echo "$HASH" > /tmp/commit_hash.txt
     - name: Find commit message (PR)
       shell: bash
       id: checkout_code
       if: github.event_name == 'pull_request'
       run: |
-        echo "+++++ head commit message +++++"
-        echo "$(git log -1 --no-merges)"
-        echo "+++++++++++++++++++++++++++++++"
-        echo "hash=$(git rev-parse HEAD)" >> "$GITHUB_OUTPUT"
-        git checkout ${{ github.event.pull_request.head.sha }}
-        echo "$(git log -1 --no-merges)" >> /tmp/commit_msg.txt
+        BEFORE_HASH=$(git rev-parse HEAD)
+        echo "hash=$BEFORE_HASH" >> "$GITHUB_OUTPUT"
+        # Next we will checkout the actual head (not the merge commits) of the PR
+        AFTER_HASH="${{ github.event.pull_request.head.sha }}"
+        git checkout $AFTER_HASH
+        COMMIT_MESSAGE=$(git log -1 --no-merges)
+        echo "$COMMIT_MESSAGE" > /tmp/commit_msg.txt
+        echo "$AFTER_HASH" > /tmp/commit_hash.txt
     - shell: bash
       id: action_output
       run: |
+        # Get the commit message
         DELIMITER="EOF_FILE_CONTENT_$(date +%s)" # Using timestamp to make it more unique
         echo "msg<<$DELIMITER" >> "$GITHUB_OUTPUT"
         cat /tmp/commit_msg.txt >> "$GITHUB_OUTPUT"
         echo "$DELIMITER" >> "$GITHUB_OUTPUT"
-        echo "----- got commit message ---"
-        cat /tmp/commit_msg.txt
-        echo "----------------------------"
+        # Get the commit hash
+        echo "hash=$(cat /tmp/commit_hash.txt)" >> "$GITHUB_OUTPUT"
     - name: Cleanup Find commit message (PR)
       shell: bash
       if: github.event_name == 'pull_request'

.github/workflows/postsubmit.yml

@@ -23,7 +23,7 @@ jobs:
           GH_TOKEN: ${{ secrets.FILAMENTBOT_TOKEN }}
         run: |
           GOLDEN_BRANCH=$(echo "${{ steps.get_commit_msg.outputs.msg }}" | python3 test/renderdiff/src/commit_msg.py)
-          COMMIT_HASH=$(echo "${{ steps.get_commit_msg.outputs.msg }}" | head -n 1 | sed "s/commit //g")
+          COMMIT_HASH="${{ steps.get_commit_msg.outputs.hash }}"
           if [[ "${GOLDEN_BRANCH}" != "main" ]]; then
               git config --global user.email "filament.bot@gmail.com"
               git config --global user.name "Filament Bot"
@@ -51,7 +51,7 @@ jobs:
           GH_TOKEN: ${{ secrets.FILAMENTBOT_TOKEN }}
         run: |
           bash docs_src/build/install_mdbook.sh && source ~/.bashrc
-          COMMIT_HASH=$(echo "${{ steps.get_commit_msg.outputs.msg }}" | head -n 1 | sed "s/commit //g")
+          COMMIT_HASH="${{ steps.get_commit_msg.outputs.hash }}"
           git config --global user.email "filament.bot@gmail.com"
           git config --global user.name "Filament Bot"
           git config --global credential.helper cache

.github/workflows/presubmit.yml

@@ -108,8 +108,7 @@ jobs:
         uses: ./.github/actions/get-commit-msg
       - name: Check for manual edits to /docs
         run: |
-          COMMIT_ID=$(echo "${{ steps.get_commit_msg.outputs.msg }}" | head -n 1 | sed "s/commit //g")
-          bash docs_src/build/presubmit_check.sh ${COMMIT_ID}
+          bash docs_src/build/presubmit_check.sh ${{ steps.get_commit_msg.outputs.hash }}
 
   test-renderdiff:
     name: test-renderdiff
@@ -121,7 +120,7 @@ jobs:
       - uses: ./.github/actions/mac-prereq
       - uses: ./.github/actions/get-gltf-assets
       - uses: ./.github/actions/get-mesa
-      - uses: ./.github/actions/get-vulkan-sdk      
+      - uses: ./.github/actions/get-vulkan-sdk
       - id: get_commit_msg
         uses: ./.github/actions/get-commit-msg
       - name: Prerequisites
@@ -132,12 +131,14 @@ jobs:
         shell: bash
       - name: Render and compare
         id: render_compare
+        env:
+          COMMIT_MESSAGE: ${{ steps.get_commit_msg.outputs.msg }}
         run: |
           ls ./gltf/Models
           TEST_DIR=test/renderdiff
           source ${TEST_DIR}/src/preamble.sh
           start_
-          GOLDEN_BRANCH=$(echo "${{ steps.get_commit_msg.outputs.msg }}" | python3 ${TEST_DIR}/src/commit_msg.py)
+          GOLDEN_BRANCH=$(echo "${COMMIT_MESSAGE}" | python3 ${TEST_DIR}/src/commit_msg.py)
           bash ${TEST_DIR}/generate.sh && \
               python3 ${TEST_DIR}/src/golden_manager.py \
                   --branch=${GOLDEN_BRANCH} \
@@ -178,7 +179,7 @@ jobs:
           fetch-depth: 0
       - uses: ./.github/actions/linux-prereq
       - name: Run build script
-        run: ./build.sh -W debug test_filamat filament
+        run: ./build.sh -W debug test_filamat filament gltf_viewer
       - name: Run test
         run: ./out/cmake-debug/libs/filamat/test_filamat --gtest_filter=MaterialCompiler.Wgsl*
 
@@ -202,3 +203,23 @@ jobs:
           ./build.sh -p desktop debug gltf_viewer
       - name: Run test
         run: bash test/code-correctness/test.sh
+
+  test-backend:
+    name: test-backend
+    runs-on: macos-14-xlarge
+    steps:
+      - uses: actions/checkout@v4.1.6
+        with:
+          fetch-depth: 0
+      - uses: ./.github/actions/mac-prereq
+      - uses: ./.github/actions/get-mesa
+      - uses: ./.github/actions/get-vulkan-sdk
+      - name: Prerequisites
+        run: |
+          # Must have at least clang-16 for a webgpu/dawn build.
+          sudo xcode-select -s /Applications/Xcode_16.2.app/Contents/Developer
+        shell: bash
+      - name: Run backend tests
+        shell: bash
+        run: |
+          bash test/backend/test.sh

BUILDING.md

@@ -62,6 +62,11 @@ force a clean build by adding the `-c` flag in that case.
 To install the libraries and executables in `out/debug/` and `out/release/`, add the `-i` flag.
 The script offers more features described by executing `build.sh -h`.
 
+For more specialized options, please also consider the following pages:
+ - `-d`: [`matdbg`](https://google.github.io/filament/dup/matdbg.html)
+ - `-t`: [`fgviewer`](https://google.github.io/filament/dup/fgviewer.html)
+ - `-b` and `-y`: [ASAN/UBSAN builds](https://google.github.io/filament/notes/asan_ubsan.html)
+
 ### Filament-specific CMake Options
 
 The following CMake options are boolean options specific to Filament:
@@ -391,7 +396,7 @@ Alternatively, if you have node installed you can use the
 [live-server](https://www.npmjs.com/package/live-server) package, which automatically refreshes the
 web page when it detects a change.
 
-Each sample app has its own handwritten html file. Additionally the server folder contains assets
+Each sample app has its own handwritten html file. Additionally, the server folder contains assets
 such as meshes, textures, and materials.
 
 ## Running the native samples

CMakeLists.txt

@@ -56,6 +56,10 @@ option(FILAMENT_ENABLE_FGVIEWER "Enable the frame graph viewer" OFF)
 
 option(FILAMENT_USE_ABSEIL_LOGGING "Use Abseil to log, may increase binary size" OFF)
 
+option(FILAMENT_ENABLE_EXPERIMENTAL_GCC_SUPPORT "Enable GCC support (unsupported)" OFF)
+
+option(FILAMENT_SUPPORTS_WEBP_TEXTURES "Enable webp texture support for Filament (builds libwebp when ON)" OFF)
+
 # This is to disable GTAO for the short-term while we investigate a way to better manage size increases.
 # On the regular filament build (where size is of less concern), we enable GTAO by default.
 option(FILAMENT_DISABLE_GTAO "Disable GTAO" OFF)
@@ -295,15 +299,10 @@ set(TOOLS ${CMAKE_CURRENT_SOURCE_DIR}/tools)
 # ==================================================================================================
 set(MIN_CLANG_VERSION "6.0")
 
-if (CMAKE_C_COMPILER_ID MATCHES "Clang")
-    if (CMAKE_C_COMPILER_VERSION VERSION_LESS MIN_CLANG_VERSION)
-        message(FATAL_ERROR "Detected C compiler Clang ${CMAKE_C_COMPILER_VERSION} < ${MIN_CLANG_VERSION}")
-    endif()
-elseif (NOT MSVC)
-    message(FATAL_ERROR "Detected C compiler ${CMAKE_C_COMPILER_ID} is unsupported")
-endif()
-
-if (CMAKE_CXX_COMPILER_ID MATCHES "Clang")
+set(FILAMENT_USING_GCC OFF)
+if (CMAKE_C_COMPILER_ID MATCHES "GNU" AND FILAMENT_ENABLE_EXPERIMENTAL_GCC_SUPPORT)
+    set(FILAMENT_USING_GCC ON)
+elseif (CMAKE_C_COMPILER_ID MATCHES "Clang")
     if (CMAKE_CXX_COMPILER_VERSION VERSION_LESS MIN_CLANG_VERSION)
         message(FATAL_ERROR "Detected CXX compiler Clang ${CMAKE_CXX_COMPILER_VERSION} < ${MIN_CLANG_VERSION}")
     endif()
@@ -344,14 +343,18 @@ if (MSVC)
     set(CXX_STANDARD "/std:c++latest")
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${CXX_STANDARD} /W0 /Zc:__cplusplus")
 else()
-    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${CXX_STANDARD} -fstrict-aliasing -Wno-unknown-pragmas -Wno-unused-function -Wno-deprecated-declarations")
+    if(FILAMENT_USING_GCC)
+      set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${CXX_STANDARD} -Wno-changes-meaning -Wno-return-type -Wno-attributes -Wno-unknown-pragmas -Wno-class-memaccess -Wno-multichar -Wno-deprecated-declarations -Wno-subobject-linkage -Wno-invalid-constexpr")
+    else()
+      set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${CXX_STANDARD} -fstrict-aliasing -Wno-unknown-pragmas -Wno-unused-function -Wno-deprecated-declarations")
+    endif()
     if (APPLE)
         set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-nullability-extension")
     endif()
 endif()
 
 if (FILAMENT_USE_EXTERNAL_GLES3)
-    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -DUSE_EXTERNAL_GLES3")
+    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -DFILAMENT_USE_EXTERNAL_GLES3")
 endif()
 
 if (FILAMENT_SUPPORTS_EGL_ON_LINUX)
@@ -365,10 +368,14 @@ endif()
 if (LINUX)
     option(USE_STATIC_LIBCXX "Link against the static runtime libraries." ON)
     if (${USE_STATIC_LIBCXX})
-        set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -stdlib=libc++")
-        link_libraries("-static-libgcc -static-libstdc++")
-        link_libraries(libc++.a)
-        link_libraries(libc++abi.a)
+        if (FILAMENT_USING_GCC)
+            link_libraries("-static-libgcc -static-libstdc++")
+        else ()
+            set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -stdlib=libc++")
+            link_libraries("-static-libgcc -static-libstdc++")
+            link_libraries(libc++.a)
+            link_libraries(libc++abi.a)
+        endif()
     endif()
 
     # Only linux, clang doesn't want to use a shared library that is not PIC.
@@ -393,8 +400,8 @@ if (MSVC)
     set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -D_CRT_SECURE_NO_WARNINGS -D_CRT_NONSTDC_NO_DEPRECATE")
 endif()
 
-# Add colors to ninja builds
-if (UNIX AND CMAKE_GENERATOR STREQUAL "Ninja")
+# Add colors to ninja builds (when not using gcc)
+if (UNIX AND CMAKE_GENERATOR STREQUAL "Ninja" AND NOT FILAMENT_USING_GCC)
     set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -fcolor-diagnostics")
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fcolor-diagnostics")
 endif()
@@ -748,12 +755,61 @@ function(combine_static_libs TARGET OUTPUT DEPS)
 endfunction()
 
 # ==================================================================================================
-# Configuration for CMAKE_CROSSCOMPILING.
+# Configuration importing/exporting prebuilt "/tools" executables
 # ==================================================================================================
+
+# In certain cases, we want the ability to separate the build type/flags (release, debug) of tools
+# (matc, resgen, etc...) from filament.  Cross compilation is one such case (e.g. building material
+# with matc running on host while building filament for Android) [1]. Another example is when client
+# wants to enable ASAN for filament but not the tool [2].
+#
+# Here are the varibles that are used to determine behavior is such flows:
+#   - CMAKE_CROSSCOMPILING : Set by cmake to indicate the build's target platform is different
+#     from the host platform.
+#   - IMPORT_EXECUTABLES_DIR : This is the directory containing the /ImportExecutables-type.cmake
+#     which are then included in other CMakeLists.txt to enable finding targets that have been
+#     prebuilt. This is set by the client in their `cmake` invocation.
+#   - IMPORT_EXECUTABLES : Path to a file to for 1) exporting the prebuilt targets or 2)
+#     importing a previously exported targets. (Used internally and should not be set by client).
+#   - FILAMENT_EXPORT_PREBUILT_EXECUTABLES_DIR : A path set by the client to indicate that
+#     they wish to export the tools as prebuilts, and the corresponding targets will be recorded
+#     in a cmake file (i.e IMPORT_EXECUTABLES). IMPORT_EXECUTABLES will be set relative to the the
+#     given path. This will set FILAMENT_EXPORT_PREBUILT_EXECUTABLES=ON.
+#   - FILAMENT_IMPORT_PREBUILT_EXECUTABLES_DIR : A path set by the client to indicate that they wish
+#     to import the tools as prebuilts from a .cmake file. The location (IMPORT_EXECUTABLES) of the
+#     file is relative to the path given. This will set FILAMENT_IMPORT_PREBUILT_EXECUTABLES=ON.
+#   - IMPORT_PREBUILT_EXECUTABLES and EXPORT_PREBUILT_EXECUTABLES are internal booleans set to
+#     ON based on the prescence of FILAMENT_IMPORT_PREBUILT_EXECUTABLES_DIR and
+#     FILAMENT_EXPORT_PREBUILT_EXECUTABLES_DIR.
+#
+# In conclusion, for cases
+#   - [1] (crosscompiling), the client must set IMPORT_EXECUTABLES_DIR for both when they are building
+#     the tools and when they are building the target-platform filament.
+#   - [2] (all other instances), the client must set FILAMENT_EXPORT_PREBUILT_EXECUTABLES_DIR in
+#     the prebuilt exporting step, and set FILAMENT_IMPORT_PREBUILT_EXECUTABLES_DIR in the importing
+#     step.
+
+# TODO: Fold the cross compilation case into the more general FILAMENT_IMPORT/EXPORT variables.
+
+if (FILAMENT_EXPORT_PREBUILT_EXECUTABLES_DIR)
+   set(FILAMENT_EXPORT_PREBUILT_EXECUTABLES ON)
+   set(IMPORT_EXECUTABLES_DIR ${FILAMENT_EXPORT_PREBUILT_EXECUTABLES_DIR})
+endif()
+
+if (FILAMENT_IMPORT_PREBUILT_EXECUTABLES_DIR)
+   set(FILAMENT_IMPORT_PREBUILT_EXECUTABLES ON)
+   set(IMPORT_EXECUTABLES_DIR ${FILAMENT_IMPORT_PREBUILT_EXECUTABLES_DIR})
+endif()
+
 if (WEBGL)
     set(IMPORT_EXECUTABLES ${FILAMENT}/${IMPORT_EXECUTABLES_DIR}/ImportExecutables-Release.cmake)
 else()
-    set(IMPORT_EXECUTABLES ${FILAMENT}/${IMPORT_EXECUTABLES_DIR}/ImportExecutables-${CMAKE_BUILD_TYPE}.cmake)
+    if (FILAMENT_EXPORT_PREBUILT_EXECUTABLES OR FILAMENT_IMPORT_PREBUILT_EXECUTABLES)
+        set(IMPORT_EXECUTABLES_BUILD_TYPE Prebuilt)
+    else()
+        set(IMPORT_EXECUTABLES_BUILD_TYPE ${CMAKE_BUILD_TYPE})
+    endif()
+    set(IMPORT_EXECUTABLES ${FILAMENT}/${IMPORT_EXECUTABLES_DIR}/ImportExecutables-${IMPORT_EXECUTABLES_BUILD_TYPE}.cmake)
 endif()
 
 # ==================================================================================================
@@ -832,6 +888,7 @@ add_subdirectory(${EXTERNAL}/getopt)
 add_subdirectory(${EXTERNAL}/perfetto/tnt)
 add_subdirectory(${EXTERNAL}/zstd/tnt)
 
+
 # Note that this has to be placed after mikktspace in order for combine_static_libs to work.
 add_subdirectory(${LIBRARIES}/geometry)
 
@@ -854,6 +911,11 @@ if (FILAMENT_ENABLE_FGVIEWER)
     add_subdirectory(${LIBRARIES}/fgviewer)
 endif()
 
+if (FILAMENT_SUPPORTS_WEBP_TEXTURES)
+    add_subdirectory(${EXTERNAL}/libwebp/tnt)
+    add_definitions(-DFILAMENT_SUPPORTS_WEBP_TEXTURES)
+endif()
+
 if (FILAMENT_SUPPORTS_VULKAN)
     add_subdirectory(${LIBRARIES}/bluevk)
     add_subdirectory(${EXTERNAL}/vkmemalloc/tnt)
@@ -912,6 +974,6 @@ if (IS_HOST_PLATFORM)
 endif()
 
 # Generate exported executables for cross-compiled builds (Android, WebGL, and iOS)
-if (NOT CMAKE_CROSSCOMPILING)
+if ((NOT CMAKE_CROSSCOMPILING AND NOT FILAMENT_IMPORT_PREBUILT_EXECUTABLES) OR FILAMENT_EXPORT_PREBUILT_EXECUTABLES)
     export(TARGETS matc cmgen filamesh mipgen resgen uberz glslminifier FILE ${IMPORT_EXECUTABLES})
 endif()

CODE_STYLE.md

@@ -20,7 +20,7 @@ The guiding principles of the filament code style and code formatting can be res
 - class access modifiers are not indented
 - last line of `.cpp` or `.h` file must be an empty line
 
-```
+```c++
 for (int i = 0; i < max; i++) {
 }
 
@@ -73,12 +73,24 @@ src/data.inc
 - `public` class attributes *are not* prefixed
 - class attributes and methods are lower camelcase
 
-```
+```c++
 extern int gGlobalWarming;
 
 class FooBar {
 public:
-    void methodName();
+    FooBar(int attributeName, int sizeInBytes)
+            : mAttributeName(attributeName),
+              sizeInBytes(sizeInBytes) {}
+
+    void reallyLongMethodNameWithLotsOfArguments(bool argument1,
+            int someSecondArgument, int bestArgument) {
+        std::pair<bool, int> pair = {
+            argument1,
+            argument2,
+        };
+        // etc
+    }
+
     int sizeInBytes;
 private:
     int mAttributeName;
@@ -97,7 +109,7 @@ private:
 - always include the copyright notice at the top of every file
 - make sure the date is correct
 
-```
+```c++
 /*
  * Copyright (C) 2018 The Android Open Source Project
  *
@@ -139,7 +151,7 @@ conversely containers and algorithms are not allowed. There are exceptions such
 
 *Sorting the headers is important to help catching missing `#include` directives.*
 
-```
+```c++
 /*
  * Copyright (C) 2018 The Android Open Source Project
  *
@@ -183,7 +195,7 @@ conversely containers and algorithms are not allowed. There are exceptions such
 ### Misc
 
 - Use `auto` only when the type appears on the same line or with iterators and lambdas.
-```
+```c++
 auto foo = new Foo();
 for (auto& i : collection) { }
 ```

NEW_RELEASE_NOTES.md

@@ -1,9 +1,12 @@
 # Filament Release Notes log
 
 **If you are merging a PR into main**: please add the release note below, under the *Release notes
-We are chaning the way Vulkan buffers are handled. We need to switch over to a managed (or view-based) model where the data stored inside the object is a proxy to a Vulkan object that can dynamically be swapped around.
 
 **If you are cherry-picking a commit into an rc/ branch**: add the release note under the
 appropriate header in [RELEASE_NOTES.md](./RELEASE_NOTES.md).
 
 ## Release notes for next branch cut
+
+- engine: add `View::getLastDynamicResolutionScale()` (b/457753622)
+
+- materials: Make Material Instances' UBO descriptor use dynamic offsets. [⚠️ **Recompile Materials**]

README.md

@@ -31,7 +31,7 @@ repositories {
 }
 
 dependencies {
-    implementation 'com.google.android.filament:filament-android:1.65.4'
+    implementation 'com.google.android.filament:filament-android:1.67.0'
 }
 ```
 
@@ -51,7 +51,7 @@ Here are all the libraries available in the group `com.google.android.filament`:
 iOS projects can use CocoaPods to install the latest release:
 
 ```shell
-pod 'Filament', '~> 1.65.4'
+pod 'Filament', '~> 1.67.0'
 ```
 
 ## Documentation

RELEASE_NOTES.md

@@ -7,6 +7,31 @@ 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).
 
+## v1.67.1
+
+- Metal: Add support for the `SwapChain::CONFIG_MSAA_4_SAMPLES` flag.
+- third_party: Optionally add libwebp to build
+  - controlled by cmake flag FILAMENT_SUPPORTS_WEBP_TEXTURES, defaults to OFF
+  - actual webp texture support for libs/gltfio coming in subsequent change
+
+## v1.67.0
+
+- materials: Add a new API getParameterTransformName that will return the value of the transformName field of a sampler
+parameter. [⚠️ **Recompile Materials**]
+
+## v1.66.2
+
+
+## v1.66.1
+
+- filamat: Removed a dependency on Glslang's deprecated SPIR-V remapper.
+  The functionality is already implemented by calling the CanonicalizeIds pass
+  in the SPIRV-Tools, and should be a non-functional change.
+
+## v1.66.0
+
+- materials: include default values of spec constants in material metadata [⚠️ **Recompile Materials**]
+
 ## v1.65.4
 
 

android/filament-android/CMakeLists.txt

@@ -51,10 +51,6 @@ add_library(bluevk STATIC IMPORTED)
 set_target_properties(bluevk PROPERTIES IMPORTED_LOCATION
         ${FILAMENT_DIR}/lib/${ANDROID_ABI}/libbluevk.a)
 
-add_library(vkshaders STATIC IMPORTED)
-set_target_properties(vkshaders PROPERTIES IMPORTED_LOCATION
-        ${FILAMENT_DIR}/lib/${ANDROID_ABI}/libvkshaders.a)
-
 if (FILAMENT_SUPPORTS_WEBGPU)
         add_library(webgpu_dawn STATIC IMPORTED)
         set_target_properties(webgpu_dawn PROPERTIES IMPORTED_LOCATION
@@ -165,7 +161,6 @@ target_link_libraries(filament-jni
     PRIVATE $<$<STREQUAL:${FILAMENT_ENABLE_MATDBG},ON>:matdbg>
     PRIVATE $<$<STREQUAL:${FILAMENT_ENABLE_MATDBG},ON>:filamat>
     PRIVATE $<$<STREQUAL:${FILAMENT_SUPPORTS_VULKAN},ON>:bluevk>
-    PRIVATE $<$<STREQUAL:${FILAMENT_SUPPORTS_VULKAN},ON>:vkshaders>
     PRIVATE $<$<STREQUAL:${FILAMENT_SUPPORTS_VULKAN},ON>:smol-v>
     PRIVATE $<$<STREQUAL:${FILAMENT_SUPPORTS_WEBGPU},ON>:webgpu_dawn>
 )

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

@@ -557,7 +557,8 @@ extern "C" JNIEXPORT void JNICALL Java_com_google_android_filament_Engine_nSetBu
         jboolean disableHandleUseAfterFreeCheck,
         jint preferredShaderLanguage,
         jboolean forceGLES2Context, jboolean assertNativeWindowIsValid,
-        jint gpuContextPriority) {
+        jint gpuContextPriority,
+        jlong sharedUboInitialSizeInBytes) {
     Engine::Builder* builder = (Engine::Builder*) nativeBuilder;
     Engine::Config config = {
             .commandBufferSizeMB = (uint32_t) commandBufferSizeMB,
@@ -576,6 +577,7 @@ extern "C" JNIEXPORT void JNICALL Java_com_google_android_filament_Engine_nSetBu
             .forceGLES2Context = (bool) forceGLES2Context,
             .assertNativeWindowIsValid = (bool) assertNativeWindowIsValid,
             .gpuContextPriority = (Engine::GpuContextPriority) gpuContextPriority,
+            .sharedUboInitialSizeInBytes = (uint32_t) sharedUboInitialSizeInBytes,
     };
     builder->config(&config);
 }

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

@@ -279,6 +279,17 @@ Java_com_google_android_filament_Material_nHasParameter(JNIEnv* env, jclass,
     return (jboolean) hasParameter;
 }
 
+extern "C" JNIEXPORT jstring JNICALL
+Java_com_google_android_filament_Material_nGetParameterTransformName(JNIEnv* env, jclass,
+        jlong nativeMaterial, jstring samplerName_) {
+    Material* material = (Material*) nativeMaterial;
+    const char* samplerName = env->GetStringUTFChars(samplerName_, 0);
+    const char* transformName = material->getParameterTransformName(samplerName);
+    jstring transformName_ = env->NewStringUTF(transformName ? transformName : "");
+    env->ReleaseStringUTFChars(samplerName_, samplerName);
+    return transformName_;
+}
+
 extern "C"
 JNIEXPORT void JNICALL
 Java_com_google_android_filament_Material_nCompile(JNIEnv *env, jclass clazz,

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

@@ -208,3 +208,19 @@ Java_com_google_android_filament_Renderer_nSetVsyncTime(JNIEnv *, jclass,
     Renderer *renderer = (Renderer *) nativeRenderer;
     renderer->setVsyncTime(steadyClockTimeNano);
 }
+
+extern "C"
+JNIEXPORT void JNICALL
+Java_com_google_android_filament_Renderer_nSkipNextFrames(JNIEnv *, jclass ,
+    jlong nativeRenderer, jint frameCount) {
+    Renderer *renderer = (Renderer *) nativeRenderer;
+    renderer->skipNextFrames(frameCount);
+}
+
+extern "C"
+JNIEXPORT jint JNICALL
+Java_com_google_android_filament_Renderer_nGetFrameToSkipCount(JNIEnv *, jclass ,
+    jlong nativeRenderer) {
+    Renderer *renderer = (Renderer *) nativeRenderer;
+    return renderer->getFrameToSkipCount();
+}

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

@@ -147,6 +147,15 @@ Java_com_google_android_filament_View_nSetDynamicResolutionOptions(JNIEnv*, jcla
     view->setDynamicResolutionOptions(options);
 }
 
+extern "C" JNIEXPORT void JNICALL
+Java_com_google_android_filament_View_nGetLastDynamicResolutionScale(JNIEnv *env, jclass, jlong nativeView, jfloatArray out_) {
+    jfloat* out = env->GetFloatArrayElements(out_, nullptr);
+    View *view = (View *) nativeView;
+    math::float2 result = view->getLastDynamicResolutionScale();
+    std::copy_n(result.v, 2, out);
+    env->ReleaseFloatArrayElements(out_, out, 0);
+}
+
 extern "C" JNIEXPORT void JNICALL
 Java_com_google_android_filament_View_nSetShadowType(JNIEnv*, jclass, jlong nativeView, jint type) {
     View* view = (View*) nativeView;
@@ -356,6 +365,7 @@ Java_com_google_android_filament_View_nSetFogOptions(JNIEnv *, jclass , jlong na
     view->setFogOptions(options);
 }
 
+
 extern "C" JNIEXPORT void JNICALL
 Java_com_google_android_filament_View_nSetBlendMode(JNIEnv *, jclass , jlong nativeView, jint blendMode) {
     View* view = (View*) nativeView;
@@ -554,3 +564,20 @@ Java_com_google_android_filament_View_nClearFrameHistory(JNIEnv *env, jclass cla
     Engine *engine = (Engine *) nativeEngine;
     view->clearFrameHistory(*engine);
 }
+
+extern "C"
+JNIEXPORT void JNICALL
+Java_com_google_android_filament_View_nSetChannelDepthClearEnabled(JNIEnv *, jclass ,
+        jlong nativeView, jint channel, jboolean enabled) {
+    View* view = (View*) nativeView;
+    view->setChannelDepthClearEnabled((uint8_t) channel, (bool) enabled);
+}
+
+extern "C"
+JNIEXPORT jboolean JNICALL
+Java_com_google_android_filament_View_nIsChannelDepthClearEnabled(JNIEnv *env, jclass clazz,
+        jlong nativeView, jint channel) {
+    // TODO: implement nIsChannelDepthClearEnabled()
+    View* view = (View*) nativeView;
+    return (jboolean)view->isChannelDepthClearEnabled((uint8_t) channel);
+}

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

@@ -99,6 +99,15 @@ final class Asserts {
         }
     }
 
+    @NonNull @Size(min = 2)
+    static float[] assertFloat2(@Nullable float[] out) {
+        if (out == null) out = new float[2];
+        else if (out.length < 2) {
+            throw new ArrayIndexOutOfBoundsException("Array length must be at least 2");
+        }
+        return out;
+    }
+
     @NonNull @Size(min = 4)
     static float[] assertFloat4(@Nullable float[] out) {
         if (out == null) out = new float[4];

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

@@ -264,7 +264,8 @@ public class Engine {
                     config.disableHandleUseAfterFreeCheck,
                     config.preferredShaderLanguage.ordinal(),
                     config.forceGLES2Context, config.assertNativeWindowIsValid,
-                    config.gpuContextPriority.ordinal());
+                    config.gpuContextPriority.ordinal(),
+                    config.sharedUboInitialSizeInBytes);
             return this;
         }
 
@@ -525,6 +526,16 @@ public class Engine {
          * GPU context priority level. Controls GPU work scheduling and preemption.
          */
         public GpuContextPriority gpuContextPriority = GpuContextPriority.DEFAULT;
+
+        /**
+         * The initial size in bytes of the shared uniform buffer used for material instance batching.
+         *
+         * If the buffer runs out of space during a frame, it will be automatically reallocated
+         * with a larger capacity. Setting an appropriate initial size can help avoid runtime
+         * reallocations, which can cause a minor performance stutter, at the cost of higher
+         * initial memory usage.
+         */
+        public long sharedUboInitialSizeInBytes = 256 * 64;
     }
 
     private Engine(long nativeEngine, Config config) {
@@ -1529,7 +1540,8 @@ public class Engine {
             boolean disableHandleUseAfterFreeCheck,
             int preferredShaderLanguage,
             boolean forceGLES2Context, boolean assertNativeWindowIsValid,
-            int gpuContextPriority);
+            int gpuContextPriority,
+            long sharedUboInitialSizeInBytes);
     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);

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

@@ -787,6 +787,21 @@ public class Material {
         return nHasParameter(getNativeObject(), name);
     }
 
+    /**
+     * 
+     * Returns the name of the transform parameter associated with the given sampler parameter.
+     * In the case the parameter doesn't have a transform name field, it will return an empty string.
+     * 
+     * @param samplerName the name of the sampler parameter to query.
+     * 
+     * @see
+     * <a href="https://google.github.io/filament/Materials.html#materialdefinitions/materialblock/general:parameters">
+     * General: parameters</a>
+     */
+    public String getParameterTransformName(@NonNull String samplerName) {
+        return nGetParameterTransformName(getNativeObject(), samplerName);
+    }
+
     /**
      * Sets the value of a bool parameter on this material's default instance.
      *
@@ -1111,4 +1126,5 @@ public class Material {
     private static native int nGetRequiredAttributes(long nativeMaterial);
 
     private static native boolean nHasParameter(long nativeMaterial, @NonNull String name);
+    private static native String nGetParameterTransformName(long nativeMaterial, @NonNull String samplerName);
 }

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

@@ -332,7 +332,7 @@ public class RenderableManager {
         }
 
         /**
-         * Set the channel this renderable is associated to. There can be 4 channels.
+         * Set the channel this renderable is associated to. There can be 8 channels.
          *
          * <p>All renderables in a given channel are rendered together, regardless of anything else.
          * They are sorted as usual within a channel.</p>
@@ -342,7 +342,7 @@ public class RenderableManager {
          * <p>Channels 0 and 1 may not have render primitives using a material with `refractionType`
          * set to `screenspace`.</p>
          *
-         * @param channel clamped to the range [0..3], defaults to 2.
+         * @param channel clamped to the range [0..7], defaults to 2.
          *
          * @return Builder reference for chaining calls.
          *
@@ -351,7 +351,7 @@ public class RenderableManager {
          * @see RenderableManager::setBlendOrderAt()
          */
         @NonNull
-        public Builder channel(@IntRange(from = 0, to = 3) int channel) {
+        public Builder channel(@IntRange(from = 0, to = 7) int channel) {
             nBuilderChannel(mNativeBuilder, channel);
             return this;
         }
@@ -730,7 +730,7 @@ public class RenderableManager {
      *
      * @see Builder#channel
      */
-    public void setChannel(@EntityInstance int i, @IntRange(from = 0, to = 3) int channel) {
+    public void setChannel(@EntityInstance int i, @IntRange(from = 0, to = 7) int channel) {
         nSetChannel(mNativeObject, i, channel);
     }
 

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

@@ -732,6 +732,22 @@ public class Renderer {
         nResetUserTime(getNativeObject());
     }
 
+    /**
+     * Requests the next frameCount frames to be skipped. For Debugging.
+     * @param frameCount number of frames to skip.
+     */
+    public void skipNextFrames(int frameCount) {
+        nSkipNextFrames(getNativeObject(), frameCount);
+    }
+
+    /**
+     * Remainder count of frame to be skipped
+     * @return remaining frames to be skipped
+     */
+    public int getFrameToSkipCount() {
+        return nGetFrameToSkipCount(getNativeObject());
+    }
+
     public long getNativeObject() {
         if (mNativeObject == 0) {
             throw new IllegalStateException("Calling method on destroyed Renderer");
@@ -773,4 +789,7 @@ public class Renderer {
             float interval, float headRoomRatio, float scaleRate, int history);
     private static native void nSetClearOptions(long nativeRenderer,
             float r, float g, float b, float a, boolean clear, boolean discard);
+
+    private static native void nSkipNextFrames(long nativeObject, int frameCount);
+    private static native int nGetFrameToSkipCount(long nativeObject);
 }

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

@@ -294,8 +294,8 @@ public class TextureSampler {
     /**
      * This controls anisotropic filtering.
      *
-     * @param anisotropy Amount of anisotropy, should be a power-of-two. The default is 0.
-     *                   The maximum permissible value is 7.
+     * @param anisotropy Amount of anisotropy, should be a power-of-two. The default is 1.
+     *                   The maximum permissible value is 128.
      */
     public void setAnisotropy(float anisotropy) {
         mSampler = nSetAnisotropy(mSampler, anisotropy);

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

@@ -25,7 +25,6 @@ import java.util.EnumSet;
 
 import static com.google.android.filament.Asserts.assertFloat3In;
 import static com.google.android.filament.Asserts.assertFloat4In;
-import static com.google.android.filament.Colors.LinearColor;
 
 import com.google.android.filament.proguard.UsedByNative;
 
@@ -291,6 +290,25 @@ public class View {
         return mViewport;
     }
 
+    /**
+     * Sets whether a channel must clear the depth buffer before all primitives are rendered.
+     * Channel depth clear is off by default for all channels.
+     * This is orthogonal to Renderer::setClearOptions().
+     * @param channel between 0 and 7
+     * @param enabled true to enable clear, false to disable
+     */
+    void setChannelDepthClearEnabled(@IntRange(from = 0, to = 7) int channel, boolean enabled) {
+        nSetChannelDepthClearEnabled(getNativeObject(), channel, enabled);
+    }
+
+    /**
+     * @param channel between 0 and 7
+     * @return true if this channel has depth clear enabled.
+     */
+    boolean isChannelDepthClearEnabled(@IntRange(from = 0, to = 7) int channel) {
+        return nIsChannelDepthClearEnabled(getNativeObject(), channel);
+    }
+
     /**
      * Sets the blending mode used to draw the view into the SwapChain.
      *
@@ -655,6 +673,21 @@ public class View {
         return mDynamicResolution;
     }
 
+    /**
+     * Returns the last dynamic resolution scale factor used by this view. This value is updated
+     * when Renderer::render(View*) is called
+     * @param out A 2-float array where the value will be stored, or null in which case the array is
+     *            allocated.
+     * @return A 2-float array containing the horizontal and the vertical scale factors
+     * @see Renderer#render(View)
+     */
+    @NonNull @Size(min = 2)
+    public float[] getLastDynamicResolutionScale(@Nullable @Size(min = 2) float[] out) {
+        out = Asserts.assertFloat2(out);
+        nGetLastDynamicResolutionScale(getNativeObject(), out);
+        return out;
+    }
+
     /**
      * Sets the rendering quality for this view (e.g. color precision).
      *
@@ -1298,6 +1331,7 @@ public class View {
     private static native void nSetDithering(long nativeView, int dithering);
     private static native int nGetDithering(long nativeView);
     private static native void nSetDynamicResolutionOptions(long nativeView, boolean enabled, boolean homogeneousScaling, float minScale, float maxScale, float sharpness, int quality);
+    private static native void nGetLastDynamicResolutionScale(long nativeView, float[] out);
     private static native void nSetRenderQuality(long nativeView, int hdrColorBufferQuality);
     private static native void nSetDynamicLightingOptions(long nativeView, float zLightNear, float zLightFar);
     private static native void nSetShadowType(long nativeView, int type);
@@ -1318,6 +1352,8 @@ public class View {
             boolean lensFlare, boolean starburst, float chromaticAberration, int ghostCount, float ghostSpacing, float ghostThreshold, float haloThickness, float haloRadius, float haloThreshold);
     private static native void nSetFogOptions(long nativeView, float distance, float maximumOpacity, float height, float heightFalloff, float cutOffDistance, float v, float v1, float v2, float density, float inScatteringStart, float inScatteringSize, boolean fogColorFromIbl, long skyColorNativeObject, boolean enabled);
     private static native void nSetStereoscopicOptions(long nativeView, boolean enabled);
+    private static native void nSetChannelDepthClearEnabled(long nativeView, int channel, boolean enabled);
+    private static native boolean nIsChannelDepthClearEnabled(long nativeView, int channel);
     private static native void nSetBlendMode(long nativeView, int blendMode);
     private static native void nSetDepthOfFieldOptions(long nativeView, float cocScale, float maxApertureDiameter, boolean enabled, int filter,
             boolean nativeResolution, int foregroundRingCount, int backgroundRingCount, int fastGatherRingCount, int maxForegroundCOC, int maxBackgroundCOC);
@@ -1615,7 +1651,7 @@ public class View {
          *
          *  This value is used as a tint instead, when fogColorFromIbl is enabled.
          *
-         *  @see fogColorFromIbl
+         *  @see #fogColorFromIbl
          */
         @NonNull @Size(min = 3)
         public float[] color = {1.0f, 1.0f, 1.0f};
@@ -1656,7 +1692,7 @@ public class View {
          *
          * `fogColorFromIbl` is ignored when skyTexture is specified.
          *
-         * @see skyColor
+         * @see #skyColor
          */
         public boolean fogColorFromIbl = false;
         /**
@@ -1674,7 +1710,7 @@ public class View {
          * In `linearFog` mode mipmap level 0 is always used.
          *
          * @see Texture
-         * @see fogColorFromIbl
+         * @see #fogColorFromIbl
          */
         @Nullable
         public Texture skyColor = null;
@@ -1796,7 +1832,8 @@ public class View {
     /**
      * Structure used to set the precision of the color buffer and related quality settings.
      *
-     * @see setRenderQuality, getRenderQuality
+     * @see #setRenderQuality
+     * @see #getRenderQuality
      */
     public static class RenderQuality {
         /**
@@ -1814,7 +1851,7 @@ public class View {
 
     /**
      * Options for screen space Ambient Occlusion (SSAO) and Screen Space Cone Tracing (SSCT)
-     * @see setAmbientOcclusionOptions()
+     * @see #setAmbientOcclusionOptions
      */
     public static class AmbientOcclusionOptions {
         public enum AmbientOcclusionType {
@@ -1966,7 +2003,7 @@ public class View {
 
     /**
      * Options for Multi-Sample Anti-aliasing (MSAA)
-     * @see setMultiSampleAntiAliasingOptions()
+     * @see #setMultiSampleAntiAliasingOptions
      */
     public static class MultiSampleAntiAliasingOptions {
         /**
@@ -1996,7 +2033,7 @@ public class View {
      * `feedback` of 0.1 effectively accumulates a maximum of 19 samples in steady state.
      * see "A Survey of Temporal Antialiasing Techniques" by Lei Yang and all for more information.
      *
-     * @see setTemporalAntiAliasingOptions()
+     * @see #setTemporalAntiAliasingOptions
      */
     public static class TemporalAntiAliasingOptions {
         public enum BoxType {
@@ -2098,7 +2135,7 @@ public class View {
 
     /**
      * Options for Screen-space Reflections.
-     * @see setScreenSpaceReflectionsOptions()
+     * @see #setScreenSpaceReflectionsOptions
      */
     public static class ScreenSpaceReflectionsOptions {
         /**
@@ -2132,7 +2169,9 @@ public class View {
 
     /**
      * List of available post-processing anti-aliasing techniques.
-     * @see setAntiAliasing, getAntiAliasing, setSampleCount
+     * @see #setAntiAliasing
+     * @see #getAntiAliasing
+     * @see #setSampleCount
      */
     public enum AntiAliasing {
         /**
@@ -2161,7 +2200,7 @@ public class View {
 
     /**
      * List of available shadow mapping techniques.
-     * @see setShadowType
+     * @see #setShadowType
      */
     public enum ShadowType {
         /**
@@ -2185,7 +2224,7 @@ public class View {
 
     /**
      * View-level options for VSM Shadowing.
-     * @see setVsmShadowOptions()
+     * @see #setVsmShadowOptions
      * @warning This API is still experimental and subject to change.
      */
     public static class VsmShadowOptions {
@@ -2226,7 +2265,7 @@ public class View {
 
     /**
      * View-level options for DPCF and PCSS Shadowing.
-     * @see setSoftShadowOptions()
+     * @see #setSoftShadowOptions
      * @warning This API is still experimental and subject to change.
      */
     public static class SoftShadowOptions {

android/filament-utils-android/src/main/java/com/google/android/filament/utils/TextureLoader.kt

@@ -40,7 +40,21 @@ fun loadTexture(engine: Engine, resources: Resources, resourceId: Int, type: Tex
     options.inPremultiplied = type == TextureType.COLOR
 
     val bitmap = BitmapFactory.decodeResource(resources, resourceId, options)
+    return buildTexture(engine, bitmap, type)
+}
 
+fun loadTexture(engine: Engine, bytes: ByteArray, type: TextureType, offset: Int = 0, length: Int = bytes.size): Texture {
+    val options = BitmapFactory.Options()
+    // Color is the only type of texture we want to pre-multiply with the alpha channel
+    // Pre-multiplication is the default behavior, so we need to turn it off here
+    options.inPremultiplied = type == TextureType.COLOR
+
+    val bitmap = BitmapFactory.decodeByteArray(bytes, offset, length, options)
+    return buildTexture(engine, bitmap, type)
+}
+
+
+private fun buildTexture(engine: Engine, bitmap: Bitmap, type: TextureType): Texture {
     val texture = Texture.Builder()
             .width(bitmap.width)
             .height(bitmap.height)

android/filament-utils-android/src/main/java/com/google/android/filament/utils/Utils.kt

@@ -22,6 +22,7 @@ object Utils {
     /**
      * Initializes the utils JNI layer. Must be called before using any utils functionality.
      */
+    @JvmStatic
     fun init() {
         // Load Filament first to ensure that the NioUtils Java class is available in the JNIEnv.
         Filament.init()

android/gradle.properties

@@ -1,5 +1,5 @@
 GROUP=com.google.android.filament
-VERSION_NAME=1.65.4
+VERSION_NAME=1.67.0
 
 POM_DESCRIPTION=Real-time physically based rendering engine for Android.
 

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

@@ -17,12 +17,20 @@ filamentTools {
 }
 
 // don't forget to update MainACtivity.kt when/if changing this.
-tasks.register('copyMesh', Copy) {
+tasks.register('copyDamagedHelmetGltf', Copy) {
+    from file("../../../third_party/models/DamagedHelmet/DamagedHelmet.glb")
+    into file("src/main/assets/models")
+    rename {String fileName -> "helmet.glb"}
+}
+
+// don't forget to update MainACtivity.kt when/if changing this.
+tasks.register('copyBusterGltf', Copy) {
     from "../../../third_party/models/BusterDrone"
     into "src/main/assets/models"
 }
 
-preBuild.dependsOn copyMesh
+preBuild.dependsOn copyDamagedHelmetGltf
+preBuild.dependsOn copyBusterGltf
 
 clean.doFirst {
     delete "src/main/assets"

android/samples/sample-material-instance-stress/.gitignore

@@ -0,0 +1,12 @@
+*.iml
+.gradle
+/local.properties
+/.idea/workspace.xml
+/.idea/libraries
+/.idea/caches
+/.idea/gradle.xml
+.DS_Store
+/build
+/captures
+/src/main/assets
+.externalNativeBuild

android/samples/sample-material-instance-stress/build.gradle

@@ -0,0 +1,52 @@
+plugins {
+    id 'com.android.application'
+    id 'kotlin-android'
+    id 'filament-tools-plugin'
+}
+
+project.ext.isSample = true
+
+kotlin {
+    jvmToolchain(versions.jdk)
+}
+
+filamentTools {
+    materialInputDir = project.layout.projectDirectory.dir("src/main/materials")
+    materialOutputDir = project.layout.projectDirectory.dir("src/main/assets/materials")
+}
+
+clean.doFirst {
+    delete "src/main/assets"
+}
+android {
+    namespace 'com.google.android.filament.materialinstancestress'
+
+    compileSdkVersion versions.compileSdk
+    defaultConfig {
+        applicationId "com.google.android.filament.materialinstancestress"
+        minSdkVersion versions.minSdk
+        targetSdkVersion versions.targetSdk
+    }
+
+    // NOTE: This is a workaround required because the AGP task collectReleaseDependencies
+    //       is not configuration-cache friendly yet; this is only useful for Play publication
+    dependenciesInfo {
+        includeInApk = false
+    }
+
+    // We use the .filamat extension for materials compiled with matc
+    // Telling aapt to not compress them allows to load them efficiently
+    aaptOptions {
+        noCompress 'filamat', 'ktx'
+    }
+
+    compileOptions {
+        sourceCompatibility versions.jdk
+        targetCompatibility versions.jdk
+    }
+}
+
+dependencies {
+    implementation deps.kotlin
+    implementation project(':filament-android')
+}

android/samples/sample-material-instance-stress/src/main/AndroidManifest.xml

@@ -0,0 +1,22 @@
+<?xml version="1.0" encoding="utf-8"?>
+<manifest xmlns:android="http://schemas.android.com/apk/res/android">
+
+  <application
+      android:allowBackup="true"
+      android:icon="@mipmap/ic_launcher"
+      android:label="@string/app_name"
+      android:roundIcon="@mipmap/ic_launcher_round"
+      android:supportsRtl="true"
+      android:theme="@style/AppTheme">
+    <activity
+        android:exported="true"
+        android:name=".MainActivity">
+      <intent-filter>
+        <action android:name="android.intent.action.MAIN"/>
+
+        <category android:name="android.intent.category.LAUNCHER"/>
+      </intent-filter>
+    </activity>
+  </application>
+
+</manifest>

android/samples/sample-material-instance-stress/src/main/java/com/google/android/filament/materialinstancestress/MainActivity.kt

@@ -0,0 +1,532 @@
+/*
+ * Copyright (C) 2025 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.android.filament.materialinstancestress
+
+import android.animation.ValueAnimator
+import android.app.Activity
+import android.opengl.Matrix
+import android.os.Bundle
+import android.view.Choreographer
+import android.view.Surface
+import android.view.SurfaceView
+import android.view.animation.LinearInterpolator
+
+import com.google.android.filament.*
+import com.google.android.filament.RenderableManager.*
+import com.google.android.filament.VertexBuffer.*
+import com.google.android.filament.android.DisplayHelper
+import com.google.android.filament.android.FilamentHelper
+import com.google.android.filament.android.UiHelper
+
+import java.nio.ByteBuffer
+import java.nio.ByteOrder
+import java.nio.channels.Channels
+import kotlin.math.cos
+import kotlin.math.sin
+
+class MainActivity : Activity() {
+    // Make sure to initialize Filament first
+    // This loads the JNI library needed by most API calls
+    companion object {
+        init {
+            Filament.init()
+        }
+
+        private const val NUM_CUBES = 1000
+        private const val GRID_SIZE = 10
+        private const val SPACING = 2.5f
+    }
+
+    // The View we want to render into
+    private lateinit var surfaceView: SurfaceView
+    // UiHelper is provided by Filament to manage SurfaceView and SurfaceTexture
+    private lateinit var uiHelper: UiHelper
+    // DisplayHelper is provided by Filament to manage the display
+    private lateinit var displayHelper: DisplayHelper
+    // Choreographer is used to schedule new frames
+    private lateinit var choreographer: Choreographer
+
+    // Engine creates and destroys Filament resources
+    // Each engine must be accessed from a single thread of your choosing
+    // Resources cannot be shared across engines
+    private lateinit var engine: Engine
+    // A renderer instance is tied to a single surface (SurfaceView, TextureView, etc.)
+    private lateinit var renderer: Renderer
+    // A scene holds all the renderable, lights, etc. to be drawn
+    private lateinit var scene: Scene
+    // A view defines a viewport, a scene and a camera for rendering
+    private lateinit var view: View
+    // Should be pretty obvious :)
+    private lateinit var camera: Camera
+
+    private lateinit var material: Material
+    private lateinit var vertexBuffer: VertexBuffer
+    private lateinit var indexBuffer: IndexBuffer
+
+    // Filament entity representing a renderable object
+    @Entity private val renderables = IntArray(NUM_CUBES)
+    private val materialInstances = arrayOfNulls<MaterialInstance>(NUM_CUBES)
+    private val translationMatrices = Array(NUM_CUBES) { FloatArray(16) }
+
+    @Entity private var light = 0
+
+    // A swap chain is Filament's representation of a surface
+    private var swapChain: SwapChain? = null
+
+    private var cameraRadius = 42.7f // Initial distance (calculated from original 15Y, 40Z)
+    private var cameraTheta = 0.0f  // Azimuth (horizontal) in radians
+    private var cameraPhi = 0.358f  // Elevation (vertical) in radians (from original 15Y, 40Z)
+
+    private var mLastX = 0.0f
+    private var mLastY = 0.0f
+    private val DRAG_SPEED = 0.005f
+
+    // Performs the rendering and schedules new frames
+    private val frameScheduler = FrameCallback()
+
+    private val animator = ValueAnimator.ofFloat(0.0f, 360.0f)
+
+    private val animatorListener = object : ValueAnimator.AnimatorUpdateListener {
+        // Pre-allocate matrix to avoid GC churn
+        private val transformMatrix = FloatArray(16)
+
+        override fun onAnimationUpdate(a: ValueAnimator) {
+            val tcm = engine.transformManager
+            val time = a.animatedFraction // 0.0 to 1.0
+
+            // Calculate the sine wave scale factor.
+            // sin(time * 2 * PI) oscillates between -1.0 and 1.0.
+            // We multiply by 0.5f (so it's -0.5 to 0.5) and add 1.0f.
+            // This makes the final 'scale' oscillate between 0.5 and 1.5.
+            val scale = 1.0f + sin(time * 2.0 * Math.PI).toFloat() * 0.5f
+
+            val localScale = (scale - 0.5f) * 0.5f + 0.5f
+
+            for (i in 0 until NUM_CUBES) {
+                val inst = tcm.getInstance(renderables[i])
+                val materialInst = materialInstances[i] ?: continue
+
+                // Get the cube's base position from its stored matrix
+                // The translation is in elements 12 (x), 13 (y), and 14 (z)
+                val baseX = translationMatrices[i][12]
+                val baseY = translationMatrices[i][13]
+                val baseZ = translationMatrices[i][14]
+
+                // Set the transformMatrix to a new translation matrix,
+                // scaled from the center (0,0,0)
+                Matrix.setIdentityM(transformMatrix, 0)
+                Matrix.translateM(transformMatrix, 0,
+                        baseX * scale,
+                        baseY * scale,
+                        baseZ * scale)
+                Matrix.scaleM(transformMatrix, 0, localScale, localScale, localScale)
+
+                tcm.setTransform(inst, transformMatrix)
+
+                // Vary roughness
+                val roughness = 0.5f + 0.5f * sin(time * 2.0 * Math.PI + i * 0.1).toFloat()
+                materialInst.setParameter("roughness", roughness)
+
+                // Vary color (using linear RGB)
+                val r = 0.5f + 0.5f * cos(time * 2.0 * Math.PI + i * 0.5).toFloat()
+                val g = 0.5f + 0.5f * sin(time * 2.0 * Math.PI + i * 0.3).toFloat()
+                val b = 0.5f + 0.5f * cos(time * 2.0 * Math.PI + i * 0.1).toFloat()
+                materialInst.setParameter("baseColor", Colors.RgbType.LINEAR, r, g, b)
+            }
+        }
+    }
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+
+        surfaceView = SurfaceView(this)
+        setContentView(surfaceView)
+
+        surfaceView.setOnTouchListener(touchListener)
+        choreographer = Choreographer.getInstance()
+
+        displayHelper = DisplayHelper(this)
+
+        setupSurfaceView()
+        setupFilament()
+        setupView()
+        setupScene()
+    }
+
+    private fun setupSurfaceView() {
+        uiHelper = UiHelper(UiHelper.ContextErrorPolicy.DONT_CHECK)
+        uiHelper.renderCallback = SurfaceCallback()
+        uiHelper.attachTo(surfaceView)
+    }
+
+    private fun setupFilament() {
+        engine = Engine.create()
+        renderer = engine.createRenderer()
+        scene = engine.createScene()
+        view = engine.createView()
+        camera = engine.createCamera(engine.entityManager.create())
+    }
+
+    private fun setupView() {
+        scene.skybox = Skybox.Builder().color(0.035f, 0.035f, 0.035f, 1.0f).build(engine)
+        view.camera = camera
+        view.scene = scene
+    }
+
+    private fun setupScene() {
+        loadMaterial()
+        createMesh()
+
+        val tcm = engine.transformManager
+        val center = (GRID_SIZE - 1) * 0.5f
+
+        for (i in 0 until NUM_CUBES) {
+            // Calculate grid position
+            val x = (i % GRID_SIZE) - center
+            val y = ((i / GRID_SIZE) % GRID_SIZE) - center
+            val z = (i / (GRID_SIZE * GRID_SIZE)) - center
+
+            val posX = x * SPACING
+            val posY = y * SPACING
+            val posZ = z * SPACING
+
+            // Create material instance for this cube
+            materialInstances[i] = material.createInstance()
+
+            // Set initial parameters (will be overwritten by animator, but good practice)
+            materialInstances[i]?.setParameter("baseColor", Colors.RgbType.SRGB, 1.0f, 0.85f, 0.57f)
+            materialInstances[i]?.setParameter("metallic", 0.0f)
+            materialInstances[i]?.setParameter("roughness", 0.3f)
+
+            // Create the renderable entity
+            renderables[i] = EntityManager.get().create()
+
+            // Create the renderable component
+            RenderableManager.Builder(1)
+                .boundingBox(Box(0.0f, 0.0f, 0.0f, 1.0f, 1.0f, 1.0f))
+                .geometry(0, PrimitiveType.TRIANGLES, vertexBuffer, indexBuffer, 0, 6 * 6)
+                .material(0, materialInstances[i]!!)
+                .build(engine, renderables[i])
+
+            // Add to scene
+            scene.addEntity(renderables[i])
+
+            // Set its initial transform
+            // Store the base translation matrix
+            Matrix.setIdentityM(translationMatrices[i], 0)
+            Matrix.translateM(translationMatrices[i], 0, posX, posY, posZ)
+
+            // Get the transform component instance
+            val inst = tcm.getInstance(renderables[i])
+            tcm.setTransform(inst, translationMatrices[i])
+        }
+
+        // We now need a light, let's create a directional light
+        light = EntityManager.get().create()
+
+        val (r, g, b) = Colors.cct(5_500.0f)
+        LightManager.Builder(LightManager.Type.DIRECTIONAL)
+                .color(r, g, b)
+                .intensity(110_000.0f)
+                .direction(0.0f, -0.5f, -1.0f)
+                .castShadows(true)
+                .build(engine, light)
+
+        scene.addEntity(light)
+
+        camera.setExposure(16.0f, 1.0f / 125.0f, 100.0f)
+
+        updateCamera()
+
+        startAnimation()
+    }
+
+    private fun loadMaterial() {
+        readUncompressedAsset("materials/lit.filamat").let {
+            material = Material.Builder().payload(it, it.remaining()).build(engine)
+        }
+    }
+
+    private fun createMesh() {
+        val floatSize = 4
+        val shortSize = 2
+        val vertexSize = 3 * floatSize + 4 * floatSize
+
+        // A vertex is a position + a tangent frame:
+        // 3 floats for XYZ position, 4 floats for normal+tangents (quaternion)
+        @Suppress("ArrayInDataClass")
+        data class Vertex(val x: Float, val y: Float, val z: Float, val tangents: FloatArray)
+        fun ByteBuffer.put(v: Vertex): ByteBuffer {
+            putFloat(v.x)
+            putFloat(v.y)
+            putFloat(v.z)
+            v.tangents.forEach { putFloat(it) }
+            return this
+        }
+
+        // 6 faces, 4 vertices per face
+        val vertexCount = 6 * 4
+
+        // Create tangent frames, one per face
+        val tfPX = FloatArray(4)
+        val tfNX = FloatArray(4)
+        val tfPY = FloatArray(4)
+        val tfNY = FloatArray(4)
+        val tfPZ = FloatArray(4)
+        val tfNZ = FloatArray(4)
+
+        MathUtils.packTangentFrame( 0.0f,  1.0f, 0.0f, 0.0f, 0.0f, -1.0f,  1.0f,  0.0f,  0.0f, tfPX)
+        MathUtils.packTangentFrame( 0.0f,  1.0f, 0.0f, 0.0f, 0.0f, -1.0f, -1.0f,  0.0f,  0.0f, tfNX)
+        MathUtils.packTangentFrame(-1.0f,  0.0f, 0.0f, 0.0f, 0.0f, -1.0f,  0.0f,  1.0f,  0.0f, tfPY)
+        MathUtils.packTangentFrame(-1.0f,  0.0f, 0.0f, 0.0f, 0.0f,  1.0f,  0.0f, -1.0f,  0.0f, tfNY)
+        MathUtils.packTangentFrame( 0.0f,  1.0f, 0.0f, 1.0f, 0.0f,  0.0f,  0.0f,  0.0f,  1.0f, tfPZ)
+        MathUtils.packTangentFrame( 0.0f, -1.0f, 0.0f, 1.0f, 0.0f,  0.0f,  0.0f,  0.0f, -1.0f, tfNZ)
+
+        val vertexData = ByteBuffer.allocate(vertexCount * vertexSize)
+                // It is important to respect the native byte order
+                .order(ByteOrder.nativeOrder())
+                // Face -Z
+                .put(Vertex(-1.0f, -1.0f, -1.0f, tfNZ))
+                .put(Vertex(-1.0f,  1.0f, -1.0f, tfNZ))
+                .put(Vertex( 1.0f,  1.0f, -1.0f, tfNZ))
+                .put(Vertex( 1.0f, -1.0f, -1.0f, tfNZ))
+                // Face +X
+                .put(Vertex( 1.0f, -1.0f, -1.0f, tfPX))
+                .put(Vertex( 1.0f,  1.0f, -1.0f, tfPX))
+                .put(Vertex( 1.0f,  1.0f,  1.0f, tfPX))
+                .put(Vertex( 1.0f, -1.0f,  1.0f, tfPX))
+                // Face +Z
+                .put(Vertex(-1.0f, -1.0f,  1.0f, tfPZ))
+                .put(Vertex( 1.0f, -1.0f,  1.0f, tfPZ))
+                .put(Vertex( 1.0f,  1.0f,  1.0f, tfPZ))
+                .put(Vertex(-1.0f,  1.0f,  1.0f, tfPZ))
+                // Face -X
+                .put(Vertex(-1.0f, -1.0f,  1.0f, tfNX))
+                .put(Vertex(-1.0f,  1.0f,  1.0f, tfNX))
+                .put(Vertex(-1.0f,  1.0f, -1.0f, tfNX))
+                .put(Vertex(-1.0f, -1.0f, -1.0f, tfNX))
+                // Face -Y
+                .put(Vertex(-1.0f, -1.0f,  1.0f, tfNY))
+                .put(Vertex(-1.0f, -1.0f, -1.0f, tfNY))
+                .put(Vertex( 1.0f, -1.0f, -1.0f, tfNY))
+                .put(Vertex( 1.0f, -1.0f,  1.0f, tfNY))
+                // Face +Y
+                .put(Vertex(-1.0f,  1.0f, -1.0f, tfPY))
+                .put(Vertex(-1.0f,  1.0f,  1.0f, tfPY))
+                .put(Vertex( 1.0f,  1.0f,  1.0f, tfPY))
+                .put(Vertex( 1.0f,  1.0f, -1.0f, tfPY))
+                // Make sure the cursor is pointing in the right place in the byte buffer
+                .flip()
+
+        // Declare the layout of our mesh
+        vertexBuffer = VertexBuffer.Builder()
+                .bufferCount(1)
+                .vertexCount(vertexCount)
+                // Because we interleave position and color data we must specify offset and stride
+                // We could use de-interleaved data by declaring two buffers and giving each
+                // attribute a different buffer index
+                .attribute(VertexAttribute.POSITION, 0, AttributeType.FLOAT3, 0,             vertexSize)
+                .attribute(VertexAttribute.TANGENTS, 0, AttributeType.FLOAT4, 3 * floatSize, vertexSize)
+                .build(engine)
+
+        // Feed the vertex data to the mesh
+        // We only set 1 buffer because the data is interleaved
+        vertexBuffer.setBufferAt(engine, 0, vertexData)
+
+        // Create the indices
+        val indexData = ByteBuffer.allocate(6 * 2 * 3 * shortSize)
+                .order(ByteOrder.nativeOrder())
+        repeat(6) {
+            val i = (it * 4).toShort()
+            indexData
+                    .putShort(i).putShort((i + 1).toShort()).putShort((i + 2).toShort())
+                    .putShort(i).putShort((i + 2).toShort()).putShort((i + 3).toShort())
+        }
+        indexData.flip()
+
+        // 6 faces, 2 triangles per face,
+        indexBuffer = IndexBuffer.Builder()
+                .indexCount(vertexCount * 2)
+                .bufferType(IndexBuffer.Builder.IndexType.USHORT)
+                .build(engine)
+        indexBuffer.setBuffer(engine, indexData)
+    }
+
+    private fun updateCamera() {
+        // Calculate eye position from spherical coordinates
+        val eyeY = cameraRadius * sin(cameraPhi)
+        val horizontalRadius = cameraRadius * cos(cameraPhi)
+        val eyeX = horizontalRadius * sin(cameraTheta)
+        val eyeZ = horizontalRadius * cos(cameraTheta)
+
+        // Point the camera at the center (0,0,0)
+        camera.lookAt(eyeX.toDouble(), eyeY.toDouble(), eyeZ.toDouble(), // eye
+                0.0, 0.0, 0.0, // center
+                0.0, 1.0, 0.0) // up
+    }
+
+    private val touchListener = object : android.view.View.OnTouchListener {
+        override fun onTouch(v: android.view.View?, event: android.view.MotionEvent?): Boolean {
+            if (event == null) return false
+            when (event.action) {
+                android.view.MotionEvent.ACTION_DOWN -> {
+                    mLastX = event.x
+                    mLastY = event.y
+                    return true
+                }
+                android.view.MotionEvent.ACTION_MOVE -> {
+                    val dx = event.x - mLastX
+                    val dy = event.y - mLastY
+
+                    cameraTheta -= dx * DRAG_SPEED
+                    cameraPhi += dy * DRAG_SPEED
+
+                    // Clamp vertical angle to avoid flipping over
+                    cameraPhi = cameraPhi.coerceIn(-1.5f, 1.5f)
+
+                    updateCamera()
+
+                    mLastX = event.x
+                    mLastY = event.y
+                    return true
+                }
+            }
+            return v?.onTouchEvent(event) ?: false
+        }
+    }
+
+    private fun startAnimation() {
+        animator.interpolator = LinearInterpolator()
+        animator.duration = 6000
+        animator.repeatMode = ValueAnimator.RESTART
+        animator.repeatCount = ValueAnimator.INFINITE
+        animator.addUpdateListener(animatorListener)
+        animator.start()
+    }
+
+    override fun onResume() {
+        super.onResume()
+        choreographer.postFrameCallback(frameScheduler)
+        animator.start()
+    }
+
+    override fun onPause() {
+        super.onPause()
+        choreographer.removeFrameCallback(frameScheduler)
+        animator.cancel()
+    }
+
+    override fun onDestroy() {
+        super.onDestroy()
+
+        // Stop the animation and any pending frame
+        choreographer.removeFrameCallback(frameScheduler)
+        animator.cancel();
+
+        // Always detach the surface before destroying the engine
+        uiHelper.detach()
+
+        // Cleanup all resources
+        engine.destroyEntity(light)
+
+        // Destroy all 1000 entities and material instances
+        for (i in 0 until NUM_CUBES) {
+            engine.destroyEntity(renderables[i])
+            materialInstances[i]?.let { engine.destroyMaterialInstance(it) }
+        }
+
+        engine.destroyRenderer(renderer)
+        engine.destroyVertexBuffer(vertexBuffer)
+        engine.destroyIndexBuffer(indexBuffer)
+        engine.destroyMaterial(material)
+        engine.destroyView(view)
+        engine.destroyScene(scene)
+        engine.destroyCameraComponent(camera.entity)
+
+        // Engine.destroyEntity() destroys Filament related resources only
+        // (components), not the entity itself
+        val entityManager = EntityManager.get()
+        entityManager.destroy(light)
+        for (entity in renderables) {
+            entityManager.destroy(entity)
+        }
+        entityManager.destroy(camera.entity)
+
+        // Destroying the engine will free up any resource you may have forgotten
+        // to destroy, but it's recommended to do the cleanup properly
+        engine.destroy()
+    }
+
+    inner class FrameCallback : Choreographer.FrameCallback {
+        override fun doFrame(frameTimeNanos: Long) {
+            // Schedule the next frame
+            choreographer.postFrameCallback(this)
+
+            // This check guarantees that we have a swap chain
+            if (uiHelper.isReadyToRender) {
+                // If beginFrame() returns false you should skip the frame
+                // This means you are sending frames too quickly to the GPU
+                if (renderer.beginFrame(swapChain!!, frameTimeNanos)) {
+                    renderer.render(view)
+                    renderer.endFrame()
+                }
+            }
+        }
+    }
+
+    inner class SurfaceCallback : UiHelper.RendererCallback {
+        override fun onNativeWindowChanged(surface: Surface) {
+            swapChain?.let { engine.destroySwapChain(it) }
+            swapChain = engine.createSwapChain(surface)
+            displayHelper.attach(renderer, surfaceView.display)
+        }
+
+        override fun onDetachedFromSurface() {
+            displayHelper.detach()
+            swapChain?.let {
+                engine.destroySwapChain(it)
+                // Required to ensure we don't return before Filament is done executing the
+                // destroySwapChain command, otherwise Android might destroy the Surface
+                // too early
+                engine.flushAndWait()
+                swapChain = null
+            }
+        }
+
+        override fun onResized(width: Int, height: Int) {
+            val aspect = width.toDouble() / height.toDouble()
+            camera.setProjection(45.0, aspect, 0.1, 100.0, Camera.Fov.VERTICAL)
+
+            view.viewport = Viewport(0, 0, width, height)
+
+            FilamentHelper.synchronizePendingFrames(engine)
+        }
+    }
+
+    private fun readUncompressedAsset(assetName: String): ByteBuffer {
+        assets.openFd(assetName).use { fd ->
+            val input = fd.createInputStream()
+            val dst = ByteBuffer.allocate(fd.length.toInt())
+
+            val src = Channels.newChannel(input)
+            src.read(dst)
+            src.close()
+
+            return dst.apply { rewind() }
+        }
+    }
+}

android/samples/sample-material-instance-stress/src/main/materials/lit.mat

@@ -0,0 +1,53 @@
+// Simple lit material that defines 3 parameters:
+// - baseColor
+// - roughness
+// - metallic
+//
+// These parameters can be used by the application to change the appearance of the material.
+//
+// This source material must be compiled to a binary material using the matc tool.
+// The command used to compile this material is:
+// matc -p mobile -a opengl -o app/src/main/assets/lit.filamat app/src/materials/lit.mat
+//
+// See build.gradle for an example of how to compile materials automatically
+// Please refer to the documentation for more information about matc and the materials system.
+
+material {
+    name : lit,
+
+    // Dynamic lighting is enabled on this material
+    shadingModel : lit,
+
+    // We don't need to declare a "requires" array, lit materials
+    // always requires the "tangents" vertex attribute (the normal
+    // is required for lighting, tangent/bitangent for normal mapping
+    // and anisotropy)
+
+    // List of parameters exposed by this material
+    parameters : [
+        // The color must be passed in linear space, not sRGB
+        {
+            type : float3,
+            name : baseColor
+        },
+        {
+            type : float,
+            name : roughness
+        },
+        {
+            type : float,
+            name : metallic
+        }
+    ],
+}
+
+fragment {
+    void material(inout MaterialInputs material) {
+        prepareMaterial(material);
+
+        // Nothing fancy here, we simply copy the parameters
+        material.baseColor.rgb = materialParams.baseColor;
+        material.roughness = materialParams.roughness;
+        material.metallic = materialParams.metallic;
+    }
+}

android/samples/sample-material-instance-stress/src/main/res/drawable-v24/ic_launcher_foreground.xml

@@ -0,0 +1,34 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:aapt="http://schemas.android.com/aapt"
+    android:width="108dp"
+    android:height="108dp"
+    android:viewportHeight="108"
+    android:viewportWidth="108">
+  <path
+      android:fillType="evenOdd"
+      android:pathData="M32,64C32,64 38.39,52.99 44.13,50.95C51.37,48.37 70.14,49.57 70.14,49.57L108.26,87.69L108,109.01L75.97,107.97L32,64Z"
+      android:strokeColor="#00000000"
+      android:strokeWidth="1">
+    <aapt:attr name="android:fillColor">
+      <gradient
+          android:endX="78.5885"
+          android:endY="90.9159"
+          android:startX="48.7653"
+          android:startY="61.0927"
+          android:type="linear">
+        <item
+            android:color="#44000000"
+            android:offset="0.0"/>
+        <item
+            android:color="#00000000"
+            android:offset="1.0"/>
+      </gradient>
+    </aapt:attr>
+  </path>
+  <path
+      android:fillColor="#FFFFFF"
+      android:fillType="nonZero"
+      android:pathData="M66.94,46.02L66.94,46.02C72.44,50.07 76,56.61 76,64L32,64C32,56.61 35.56,50.11 40.98,46.06L36.18,41.19C35.45,40.45 35.45,39.3 36.18,38.56C36.91,37.81 38.05,37.81 38.78,38.56L44.25,44.05C47.18,42.57 50.48,41.71 54,41.71C57.48,41.71 60.78,42.57 63.68,44.05L69.11,38.56C69.84,37.81 70.98,37.81 71.71,38.56C72.44,39.3 72.44,40.45 71.71,41.19L66.94,46.02ZM62.94,56.92C64.08,56.92 65,56.01 65,54.88C65,53.76 64.08,52.85 62.94,52.85C61.8,52.85 60.88,53.76 60.88,54.88C60.88,56.01 61.8,56.92 62.94,56.92ZM45.06,56.92C46.2,56.92 47.13,56.01 47.13,54.88C47.13,53.76 46.2,52.85 45.06,52.85C43.92,52.85 43,53.76 43,54.88C43,56.01 43.92,56.92 45.06,56.92Z"
+      android:strokeColor="#00000000"
+      android:strokeWidth="1"/>
+</vector>

android/samples/sample-material-instance-stress/src/main/res/drawable/ic_launcher_background.xml

@@ -0,0 +1,171 @@
+<?xml version="1.0" encoding="utf-8"?>
+<vector
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="108dp"
+    android:height="108dp"
+    android:viewportHeight="108"
+    android:viewportWidth="108">
+  <path
+      android:fillColor="#26A69A"
+      android:pathData="M0,0h108v108h-108z"/>
+  <path
+      android:fillColor="#00000000"
+      android:pathData="M9,0L9,108"
+      android:strokeColor="#33FFFFFF"
+      android:strokeWidth="0.8"/>
+  <path
+      android:fillColor="#00000000"
+      android:pathData="M19,0L19,108"
+      android:strokeColor="#33FFFFFF"
+      android:strokeWidth="0.8"/>
+  <path
+      android:fillColor="#00000000"
+      android:pathData="M29,0L29,108"
+      android:strokeColor="#33FFFFFF"
+      android:strokeWidth="0.8"/>
+  <path
+      android:fillColor="#00000000"
+      android:pathData="M39,0L39,108"
+      android:strokeColor="#33FFFFFF"
+      android:strokeWidth="0.8"/>
+  <path
+      android:fillColor="#00000000"
+      android:pathData="M49,0L49,108"
+      android:strokeColor="#33FFFFFF"
+      android:strokeWidth="0.8"/>
+  <path
+      android:fillColor="#00000000"
+      android:pathData="M59,0L59,108"
+      android:strokeColor="#33FFFFFF"
+      android:strokeWidth="0.8"/>
+  <path
+      android:fillColor="#00000000"
+      android:pathData="M69,0L69,108"
+      android:strokeColor="#33FFFFFF"
+      android:strokeWidth="0.8"/>
+  <path
+      android:fillColor="#00000000"
+      android:pathData="M79,0L79,108"
+      android:strokeColor="#33FFFFFF"
+      android:strokeWidth="0.8"/>
+  <path
+      android:fillColor="#00000000"
+      android:pathData="M89,0L89,108"
+      android:strokeColor="#33FFFFFF"
+      android:strokeWidth="0.8"/>
+  <path
+      android:fillColor="#00000000"
+      android:pathData="M99,0L99,108"
+      android:strokeColor="#33FFFFFF"
+      android:strokeWidth="0.8"/>
+  <path
+      android:fillColor="#00000000"
+      android:pathData="M0,9L108,9"
+      android:strokeColor="#33FFFFFF"
+      android:strokeWidth="0.8"/>
+  <path
+      android:fillColor="#00000000"
+      android:pathData="M0,19L108,19"
+      android:strokeColor="#33FFFFFF"
+      android:strokeWidth="0.8"/>
+  <path
+      android:fillColor="#00000000"
+      android:pathData="M0,29L108,29"
+      android:strokeColor="#33FFFFFF"
+      android:strokeWidth="0.8"/>
+  <path
+      android:fillColor="#00000000"
+      android:pathData="M0,39L108,39"
+      android:strokeColor="#33FFFFFF"
+      android:strokeWidth="0.8"/>
+  <path
+      android:fillColor="#00000000"
+      android:pathData="M0,49L108,49"
+      android:strokeColor="#33FFFFFF"
+      android:strokeWidth="0.8"/>
+  <path
+      android:fillColor="#00000000"
+      android:pathData="M0,59L108,59"
+      android:strokeColor="#33FFFFFF"
+      android:strokeWidth="0.8"/>
+  <path
+      android:fillColor="#00000000"
+      android:pathData="M0,69L108,69"
+      android:strokeColor="#33FFFFFF"
+      android:strokeWidth="0.8"/>
+  <path
+      android:fillColor="#00000000"
+      android:pathData="M0,79L108,79"
+      android:strokeColor="#33FFFFFF"
+      android:strokeWidth="0.8"/>
+  <path
+      android:fillColor="#00000000"
+      android:pathData="M0,89L108,89"
+      android:strokeColor="#33FFFFFF"
+      android:strokeWidth="0.8"/>
+  <path
+      android:fillColor="#00000000"
+      android:pathData="M0,99L108,99"
+      android:strokeColor="#33FFFFFF"
+      android:strokeWidth="0.8"/>
+  <path
+      android:fillColor="#00000000"
+      android:pathData="M19,29L89,29"
+      android:strokeColor="#33FFFFFF"
+      android:strokeWidth="0.8"/>
+  <path
+      android:fillColor="#00000000"
+      android:pathData="M19,39L89,39"
+      android:strokeColor="#33FFFFFF"
+      android:strokeWidth="0.8"/>
+  <path
+      android:fillColor="#00000000"
+      android:pathData="M19,49L89,49"
+      android:strokeColor="#33FFFFFF"
+      android:strokeWidth="0.8"/>
+  <path
+      android:fillColor="#00000000"
+      android:pathData="M19,59L89,59"
+      android:strokeColor="#33FFFFFF"
+      android:strokeWidth="0.8"/>
+  <path
+      android:fillColor="#00000000"
+      android:pathData="M19,69L89,69"
+      android:strokeColor="#33FFFFFF"
+      android:strokeWidth="0.8"/>
+  <path
+      android:fillColor="#00000000"
+      android:pathData="M19,79L89,79"
+      android:strokeColor="#33FFFFFF"
+      android:strokeWidth="0.8"/>
+  <path
+      android:fillColor="#00000000"
+      android:pathData="M29,19L29,89"
+      android:strokeColor="#33FFFFFF"
+      android:strokeWidth="0.8"/>
+  <path
+      android:fillColor="#00000000"
+      android:pathData="M39,19L39,89"
+      android:strokeColor="#33FFFFFF"
+      android:strokeWidth="0.8"/>
+  <path
+      android:fillColor="#00000000"
+      android:pathData="M49,19L49,89"
+      android:strokeColor="#33FFFFFF"
+      android:strokeWidth="0.8"/>
+  <path
+      android:fillColor="#00000000"
+      android:pathData="M59,19L59,89"
+      android:strokeColor="#33FFFFFF"
+      android:strokeWidth="0.8"/>
+  <path
+      android:fillColor="#00000000"
+      android:pathData="M69,19L69,89"
+      android:strokeColor="#33FFFFFF"
+      android:strokeWidth="0.8"/>
+  <path
+      android:fillColor="#00000000"
+      android:pathData="M79,19L79,89"
+      android:strokeColor="#33FFFFFF"
+      android:strokeWidth="0.8"/>
+</vector>

android/samples/sample-material-instance-stress/src/main/res/mipmap-anydpi-v26/ic_launcher.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<adaptive-icon xmlns:android="http://schemas.android.com/apk/res/android">
+  <background android:drawable="@drawable/ic_launcher_background"/>
+  <foreground android:drawable="@drawable/ic_launcher_foreground"/>
+</adaptive-icon>

android/samples/sample-material-instance-stress/src/main/res/mipmap-anydpi-v26/ic_launcher_round.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<adaptive-icon xmlns:android="http://schemas.android.com/apk/res/android">
+  <background android:drawable="@drawable/ic_launcher_background"/>
+  <foreground android:drawable="@drawable/ic_launcher_foreground"/>
+</adaptive-icon>

android/samples/sample-material-instance-stress/src/main/res/values/colors.xml

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+  <color name="colorPrimary">#3F51B5</color>
+  <color name="colorPrimaryDark">#303F9F</color>
+  <color name="colorAccent">#FF4081</color>
+</resources>

android/samples/sample-material-instance-stress/src/main/res/values/strings.xml

@@ -0,0 +1,3 @@
+<resources>
+  <string name="app_name">Material Instance Stress</string>
+</resources>

android/samples/sample-material-instance-stress/src/main/res/values/styles.xml

@@ -0,0 +1,8 @@
+<resources>
+
+  <!-- Base application theme. -->
+  <style name="AppTheme" parent="android:Theme.Material.Light.DarkActionBar">
+    <!-- Customize your theme here. -->
+  </style>
+
+</resources>

android/settings.gradle

@@ -12,6 +12,7 @@ include ':samples:sample-image-based-lighting'
 include ':samples:sample-lit-cube'
 include ':samples:sample-live-wallpaper'
 include ':samples:sample-material-builder'
+include ':samples:sample-material-instance-stress'
 include ':samples:sample-multi-view'
 include ':samples:sample-page-curl'
 include ':samples:sample-stream-test'

build.sh

@@ -77,6 +77,10 @@ function print_help {
     echo "        meant for building the samples."
     echo "    -P"
     echo "        Enable perfetto traces on Android. Disabled by default on the Release build, enabled otherwise."
+    echo "    -y build_type"
+    echo "        Build the filament dependent tools (matc, resgen) separately from the project. This will set"
+    echo "        the tools as prebuilts that filament target will then use to build. The built_type option"
+    echo "        (debug|release) is meant to indicate the type of build of the resulting prebuilts."
     echo ""
     echo "Build types:"
     echo "    release"
@@ -217,6 +221,11 @@ OSMESA_OPTION=""
 IOS_BUILD_SIMULATOR=false
 BUILD_UNIVERSAL_LIBRARIES=false
 
+ISSUE_SPLIT_BUILD=false
+SPLIT_BUILD_TYPE=""
+PREBUILT_TOOLS_DIR=""
+IMPORT_EXECUTABLES_DIR_OPTION="-DIMPORT_EXECUTABLES_DIR=out"
+
 BUILD_GENERATOR=Ninja
 BUILD_COMMAND=ninja
 BUILD_CUSTOM_TARGETS=
@@ -242,6 +251,37 @@ function build_clean_aggressive {
     git clean -qfX android
 }
 
+function build_tools_for_split_build {
+    local build_type_arg=$1
+    local lc_build_type=$(echo "${build_type_arg}" | tr '[:upper:]' '[:lower:]')
+    PREBUILT_TOOLS_DIR="out/prebuilt-tools-${lc_build_type}"
+
+    echo "Building tools for split build (${lc_build_type}) in ${PREBUILT_TOOLS_DIR}..."
+    mkdir -p "${PREBUILT_TOOLS_DIR}"
+
+    pushd "${PREBUILT_TOOLS_DIR}" > /dev/null
+
+    local lc_name=$(echo "${UNAME}" | tr '[:upper:]' '[:lower:]')
+    local architectures=""
+    if [[ "${lc_name}" == "darwin" ]]; then
+        if [[ "${BUILD_UNIVERSAL_LIBRARIES}" == "true" ]]; then
+            architectures="-DCMAKE_OSX_ARCHITECTURES=arm64;x86_64"
+        fi
+    fi
+
+    cmake \
+        -G "${BUILD_GENERATOR}" \
+        -DFILAMENT_EXPORT_PREBUILT_EXECUTABLES_DIR=${PREBUILT_TOOLS_DIR} \
+        -DCMAKE_BUILD_TYPE="${build_type_arg}" \
+        ${WEBGPU_OPTION} \
+        ${architectures} \
+        ../..
+
+    ${BUILD_COMMAND} ${WEB_HOST_TOOLS}
+
+    popd > /dev/null
+}
+
 function build_desktop_target {
     local lc_target=$(echo "$1" | tr '[:upper:]' '[:lower:]')
     local build_targets=$2
@@ -265,7 +305,7 @@ function build_desktop_target {
     if [[ ! -d "CMakeFiles" ]] || [[ "${ISSUE_CMAKE_ALWAYS}" == "true" ]]; then
         cmake \
             -G "${BUILD_GENERATOR}" \
-            -DIMPORT_EXECUTABLES_DIR=out \
+            ${IMPORT_EXECUTABLES_DIR_OPTION} \
             -DCMAKE_BUILD_TYPE="$1" \
             -DCMAKE_INSTALL_PREFIX="../${lc_target}/filament" \
             ${EGL_ON_LINUX_OPTION} \
@@ -331,7 +371,7 @@ function build_webgl_with_target {
         source "${EMSDK}/emsdk_env.sh"
         cmake \
             -G "${BUILD_GENERATOR}" \
-            -DIMPORT_EXECUTABLES_DIR=out \
+            ${IMPORT_EXECUTABLES_DIR_OPTION} \
             -DCMAKE_TOOLCHAIN_FILE="${EMSDK}/upstream/emscripten/cmake/Modules/Platform/Emscripten.cmake" \
             -DCMAKE_BUILD_TYPE="$1" \
             -DCMAKE_INSTALL_PREFIX="../webgl-${lc_target}/filament" \
@@ -404,7 +444,7 @@ function build_android_target {
     if [[ ! -d "CMakeFiles" ]] || [[ "${ISSUE_CMAKE_ALWAYS}" == "true" ]]; then
         cmake \
             -G "${BUILD_GENERATOR}" \
-            -DIMPORT_EXECUTABLES_DIR=out \
+            ${IMPORT_EXECUTABLES_DIR_OPTION} \
             -DCMAKE_BUILD_TYPE="$1" \
             -DFILAMENT_NDK_VERSION="${FILAMENT_NDK_VERSION}" \
             -DCMAKE_INSTALL_PREFIX="../android-${lc_target}/filament" \
@@ -638,7 +678,7 @@ function build_ios_target {
     if [[ ! -d "CMakeFiles" ]] || [[ "${ISSUE_CMAKE_ALWAYS}" == "true" ]]; then
         cmake \
             -G "${BUILD_GENERATOR}" \
-            -DIMPORT_EXECUTABLES_DIR=out \
+            ${IMPORT_EXECUTABLES_DIR_OPTION} \
             -DCMAKE_BUILD_TYPE="$1" \
             -DCMAKE_INSTALL_PREFIX="../ios-${lc_target}/filament" \
             -DIOS_ARCH="${arch}" \
@@ -810,7 +850,7 @@ function check_debug_release_build {
 
 pushd "$(dirname "$0")" > /dev/null
 
-while getopts ":hacCfgimp:q:uvWslwedtk:bVx:S:X:P" opt; do
+while getopts ":hacCfgimp:q:uvWslwedtk:bVx:S:X:Py:" opt; do
     case ${opt} in
         h)
             print_help
@@ -979,6 +1019,20 @@ while getopts ":hacCfgimp:q:uvWslwedtk:bVx:S:X:P" opt; do
             ;;
         X)  OSMESA_OPTION="-DFILAMENT_OSMESA_PATH=${OPTARG}"
             ;;
+        y)
+            ISSUE_SPLIT_BUILD=true
+            SPLIT_BUILD_TYPE=${OPTARG}
+            case $(echo "${SPLIT_BUILD_TYPE}" | tr '[:upper:]' '[:lower:]') in
+                debug|release)
+                    ;;
+                *)
+                    echo "Unknown build type for -y: ${SPLIT_BUILD_TYPE}"
+                    echo "Build type must be one of [debug|release]"
+                    echo ""
+                    exit 1
+                    ;;
+            esac
+            ;;
         \?)
             echo "Invalid option: -${OPTARG}" >&2
             echo ""
@@ -1013,6 +1067,13 @@ done
 
 validate_build_command
 
+if [[ "${ISSUE_SPLIT_BUILD}" == "true" ]]; then
+    # Capitalize first letter of SPLIT_BUILD_TYPE
+    SPLIT_BUILD_TYPE_CAPITALIZED="$(echo ${SPLIT_BUILD_TYPE:0:1} | tr '[:lower:]' '[:upper:]')${SPLIT_BUILD_TYPE:1}"
+    build_tools_for_split_build "${SPLIT_BUILD_TYPE_CAPITALIZED}"
+    IMPORT_EXECUTABLES_DIR_OPTION="-DFILAMENT_IMPORT_PREBUILT_EXECUTABLES_DIR=${PREBUILT_TOOLS_DIR}"
+fi
+
 if [[ "${ISSUE_CLEAN}" == "true" ]]; then
     build_clean
 fi

docs/build/maven_release.html

@@ -165,8 +165,8 @@ Portal</a>.</p>
 <p>To publish under the <code>com.google.android</code> namespace, you'll also need to email
 <code>central-support@sonatype.com</code> with your account information to request access.</p>
 <p>Then, generate a user token through the Sonatype website. Navigate to
-<a href="https://central.sonatype.com/account">https://central.sonatype.com/account</a> and select <strong>Generate
-User Token</strong>.</p>
+<a href="https://central.sonatype.com/usertoken">https://central.sonatype.com/usertoken</a>
+and select <strong>Generate User Token</strong>.</p>
 <p>Finally, add the generated token credentials to <code>~/.gradle/gradle.properties</code>. (Note: these are
 different from the credentials used to log into your Sonatype account):</p>
 <pre><code class="language-gradle"># Generated Sonatype token

docs/dup/bluevk.html

@@ -180,7 +180,7 @@ rm -r Vulkan-Headers-1.3.232 v1.3.232.zip
                                 <i class="fa fa-angle-left"></i>
                             </a>
 
-                            <a rel="next prefetch" href="../dup/filamat.html" class="mobile-nav-chapters next" title="Next chapter" aria-label="Next chapter" aria-keyshortcuts="Right">
+                            <a rel="next prefetch" href="../dup/fgviewer.html" class="mobile-nav-chapters next" title="Next chapter" aria-label="Next chapter" aria-keyshortcuts="Right">
                                 <i class="fa fa-angle-right"></i>
                             </a>
 
@@ -194,7 +194,7 @@ rm -r Vulkan-Headers-1.3.232 v1.3.232.zip
                         <i class="fa fa-angle-left"></i>
                     </a>
 
-                    <a rel="next prefetch" href="../dup/filamat.html" class="nav-chapters next" title="Next chapter" aria-label="Next chapter" aria-keyshortcuts="Right">
+                    <a rel="next prefetch" href="../dup/fgviewer.html" class="nav-chapters next" title="Next chapter" aria-label="Next chapter" aria-keyshortcuts="Right">
                         <i class="fa fa-angle-right"></i>
                     </a>
             </nav>

docs/dup/building.html

@@ -200,6 +200,12 @@ inside the Filament source tree.</p>
 force a clean build by adding the <code>-c</code> flag in that case.</p>
 <p>To install the libraries and executables in <code>out/debug/</code> and <code>out/release/</code>, add the <code>-i</code> flag.
 The script offers more features described by executing <code>build.sh -h</code>.</p>
+<p>For more specialized options, please also consider the following pages:</p>
+<ul>
+<li><code>-d</code>: <a href="https://google.github.io/filament/dup/matdbg.html"><code>matdbg</code></a></li>
+<li><code>-t</code>: <a href="https://google.github.io/filament/dup/fgviewer.html"><code>fgviewer</code></a></li>
+<li><code>-b</code> and <code>-y</code>: <a href="https://google.github.io/filament/notes/asan_ubsan.html">ASAN/UBSAN builds</a></li>
+</ul>
 <h3 id="filament-specific-cmake-options"><a class="header" href="#filament-specific-cmake-options">Filament-specific CMake Options</a></h3>
 <p>The following CMake options are boolean options specific to Filament:</p>
 <ul>
@@ -434,7 +440,7 @@ to create a quick localhost server:</p>
 <p>Alternatively, if you have node installed you can use the
 <a href="https://www.npmjs.com/package/live-server">live-server</a> package, which automatically refreshes the
 web page when it detects a change.</p>
-<p>Each sample app has its own handwritten html file. Additionally the server folder contains assets
+<p>Each sample app has its own handwritten html file. Additionally, the server folder contains assets
 such as meshes, textures, and materials.</p>
 <h2 id="running-the-native-samples"><a class="header" href="#running-the-native-samples">Running the native samples</a></h2>
 <p>The <code>samples/</code> directory contains several examples of how to use Filament with SDL2.</p>

docs/dup/code_style.html

@@ -179,7 +179,7 @@ Google code style and is derived from the Java code style, but not quite.</p>
 <li>class access modifiers are not indented</li>
 <li>last line of <code>.cpp</code> or <code>.h</code> file must be an empty line</li>
 </ul>
-<pre><code>for (int i = 0; i &lt; max; i++) {
+<pre><code class="language-c++">for (int i = 0; i &lt; max; i++) {
 }
 
 class Foo {
@@ -227,11 +227,23 @@ src/data.inc
 <li><code>public</code> class attributes <em>are not</em> prefixed</li>
 <li>class attributes and methods are lower camelcase</li>
 </ul>
-<pre><code>extern int gGlobalWarming;
+<pre><code class="language-c++">extern int gGlobalWarming;
 
 class FooBar {
 public:
-    void methodName();
+    FooBar(int attributeName, int sizeInBytes)
+            : mAttributeName(attributeName),
+              sizeInBytes(sizeInBytes) {}
+
+    void reallyLongMethodNameWithLotsOfArguments(bool argument1,
+            int someSecondArgument, int bestArgument) {
+        std::pair&lt;bool, int&gt; pair = {
+            argument1,
+            argument2,
+        };
+        // etc
+    }
+
     int sizeInBytes;
 private:
     int mAttributeName;
@@ -248,7 +260,7 @@ private:
 <li>always include the copyright notice at the top of every file</li>
 <li>make sure the date is correct</li>
 </ul>
-<pre><code>/*
+<pre><code class="language-c++">/*
  * Copyright (C) 2018 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
@@ -293,7 +305,7 @@ conversely containers and algorithms are not allowed. There are exceptions such
 </li>
 </ul>
 <p><em>Sorting the headers is important to help catching missing <code>#include</code> directives.</em></p>
-<pre><code>/*
+<pre><code class="language-c++">/*
  * Copyright (C) 2018 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
@@ -336,7 +348,7 @@ from other string types.</li>
 <ul>
 <li>Use <code>auto</code> only when the type appears on the same line or with iterators and lambdas.</li>
 </ul>
-<pre><code>auto foo = new Foo();
+<pre><code class="language-c++">auto foo = new Foo();
 for (auto&amp; i : collection) { }
 </code></pre>
 

docs/dup/fgviewer.html

@@ -0,0 +1,345 @@
+<!DOCTYPE HTML>
+<html lang="en" class="light sidebar-visible" dir="ltr">
+    <head>
+        <!-- Book generated using mdBook -->
+        <meta charset="UTF-8">
+        <title>fgviewer - Filament</title>
+
+
+        <!-- Custom HTML head -->
+
+        <meta name="description" content="">
+        <meta name="viewport" content="width=device-width, initial-scale=1">
+        <meta name="theme-color" content="#ffffff">
+
+        <link rel="shortcut icon" href="../favicon.png">
+        <link rel="stylesheet" href="../css/variables.css">
+        <link rel="stylesheet" href="../css/general.css">
+        <link rel="stylesheet" href="../css/chrome.css">
+
+        <!-- Fonts -->
+        <link rel="stylesheet" href="../FontAwesome/css/font-awesome.css">
+        <link rel="stylesheet" href="../fonts/fonts.css">
+
+        <!-- Highlight.js Stylesheets -->
+        <link rel="stylesheet" href="../highlight.css">
+        <link rel="stylesheet" href="../tomorrow-night.css">
+        <link rel="stylesheet" href="../ayu-highlight.css">
+
+        <!-- Custom theme stylesheets -->
+
+        <!-- MathJax -->
+        <script async src="https://cdnjs.cloudflare.com/ajax/libs/mathjax/2.7.1/MathJax.js?config=TeX-AMS-MML_HTMLorMML"></script>
+
+        <!-- Provide site root to javascript -->
+        <script>
+            var path_to_root = "../";
+            var default_theme = window.matchMedia("(prefers-color-scheme: dark)").matches ? "light" : "light";
+        </script>
+        <!-- Start loading toc.js asap -->
+        <script src="../toc.js"></script>
+    </head>
+    <body>
+    <div id="body-container">
+        <!-- Work around some values being stored in localStorage wrapped in quotes -->
+        <script>
+            try {
+                var theme = localStorage.getItem('mdbook-theme');
+                var sidebar = localStorage.getItem('mdbook-sidebar');
+
+                if (theme.startsWith('"') && theme.endsWith('"')) {
+                    localStorage.setItem('mdbook-theme', theme.slice(1, theme.length - 1));
+                }
+
+                if (sidebar.startsWith('"') && sidebar.endsWith('"')) {
+                    localStorage.setItem('mdbook-sidebar', sidebar.slice(1, sidebar.length - 1));
+                }
+            } catch (e) { }
+        </script>
+
+        <!-- Set the theme before any content is loaded, prevents flash -->
+        <script>
+            var theme;
+            try { theme = localStorage.getItem('mdbook-theme'); } catch(e) { }
+            if (theme === null || theme === undefined) { theme = default_theme; }
+            const html = document.documentElement;
+            html.classList.remove('light')
+            html.classList.add(theme);
+            html.classList.add("js");
+        </script>
+
+        <input type="checkbox" id="sidebar-toggle-anchor" class="hidden">
+
+        <!-- Hide / unhide sidebar before it is displayed -->
+        <script>
+            var sidebar = null;
+            var sidebar_toggle = document.getElementById("sidebar-toggle-anchor");
+            if (document.body.clientWidth >= 1080) {
+                try { sidebar = localStorage.getItem('mdbook-sidebar'); } catch(e) { }
+                sidebar = sidebar || 'visible';
+            } else {
+                sidebar = 'hidden';
+            }
+            sidebar_toggle.checked = sidebar === 'visible';
+            html.classList.remove('sidebar-visible');
+            html.classList.add("sidebar-" + sidebar);
+        </script>
+
+        <nav id="sidebar" class="sidebar" aria-label="Table of contents">
+            <div style="display:flex;align-items:center;justify-content:center">
+                <img class="flogo" src="../images/filament_logo_small.png"></img>
+            </div>
+            <!-- populated by js -->
+            <mdbook-sidebar-scrollbox class="sidebar-scrollbox"></mdbook-sidebar-scrollbox>
+            <noscript>
+                <iframe class="sidebar-iframe-outer" src="../toc.html"></iframe>
+            </noscript>
+            <div id="sidebar-resize-handle" class="sidebar-resize-handle">
+                <div class="sidebar-resize-indicator"></div>
+            </div>
+        </nav>
+
+        <div id="page-wrapper" class="page-wrapper">
+
+            <div class="page">
+                <div id="menu-bar-hover-placeholder"></div>
+                <div id="menu-bar" class="menu-bar sticky">
+                    <div class="left-buttons">
+                        <label id="sidebar-toggle" class="icon-button" for="sidebar-toggle-anchor" title="Toggle Table of Contents" aria-label="Toggle Table of Contents" aria-controls="sidebar">
+                            <i class="fa fa-bars"></i>
+                        </label>
+                        <!-- Filament: disable themes because the markdeep part does not look good for dark themes -->
+                        <!--
+                        <button id="theme-toggle" class="icon-button" type="button" title="Change theme" aria-label="Change theme" aria-haspopup="true" aria-expanded="false" aria-controls="theme-list">
+                            <i class="fa fa-paint-brush"></i>
+                        </button>
+                        <ul id="theme-list" class="theme-popup" aria-label="Themes" role="menu">
+                            <li role="none"><button role="menuitem" class="theme" id="light">Light</button></li>
+                            <li role="none"><button role="menuitem" class="theme" id="rust">Rust</button></li>
+                            <li role="none"><button role="menuitem" class="theme" id="coal">Coal</button></li>
+                            <li role="none"><button role="menuitem" class="theme" id="navy">Navy</button></li>
+                            <li role="none"><button role="menuitem" class="theme" id="ayu">Ayu</button></li>
+                        </ul>
+                        -->
+                        <button id="search-toggle" class="icon-button" type="button" title="Search. (Shortkey: s)" aria-label="Toggle Searchbar" aria-expanded="false" aria-keyshortcuts="S" aria-controls="searchbar">
+                            <i class="fa fa-search"></i>
+                        </button>
+                    </div>
+
+                    <h1 class="menu-title">Filament</h1>
+
+                    <div class="right-buttons">
+                        <a href="https://github.com/google/filament" title="Git repository" aria-label="Git repository">
+                            <i id="git-repository-button" class="fa fa-github"></i>
+                        </a>
+
+                    </div>
+                </div>
+
+                <div id="search-wrapper" class="hidden">
+                    <form id="searchbar-outer" class="searchbar-outer">
+                        <input type="search" id="searchbar" name="searchbar" placeholder="Search this book ..." aria-controls="searchresults-outer" aria-describedby="searchresults-header">
+                    </form>
+                    <div id="searchresults-outer" class="searchresults-outer hidden">
+                        <div id="searchresults-header" class="searchresults-header"></div>
+                        <ul id="searchresults">
+                        </ul>
+                    </div>
+                </div>
+
+                <!-- Apply ARIA attributes after the sidebar and the sidebar toggle button are added to the DOM -->
+                <script>
+                    document.getElementById('sidebar-toggle').setAttribute('aria-expanded', sidebar === 'visible');
+                    document.getElementById('sidebar').setAttribute('aria-hidden', sidebar !== 'visible');
+                    Array.from(document.querySelectorAll('#sidebar a')).forEach(function(link) {
+                        link.setAttribute('tabIndex', sidebar === 'visible' ? 0 : -1);
+                    });
+                </script>
+
+                <div id="content" class="content">
+                    <main>
+                        <h1 id="fgviewer"><a class="header" href="#fgviewer">fgviewer</a></h1>
+<ol>
+<li><a href="#capabilities">Capabilities</a></li>
+<li><a href="#setup-for-desktop">Setup for Desktop</a></li>
+<li><a href="#setup-for-android">Setup for Android</a></li>
+<li><a href="#debugger-usage">Debugger Usage</a></li>
+<li><a href="#architecture-overview">Architecture Overview</a></li>
+<li><a href="#c-server">C++ Server</a></li>
+<li><a href="#javascript-client">JavaScript Client</a></li>
+<li><a href="#http-requests">HTTP Requests</a></li>
+<li><a href="#wish-list">Wish List</a></li>
+</ol>
+<h2 id="capabilities"><a class="header" href="#capabilities">Capabilities</a></h2>
+<p>fgviewer is a library and web application for real-time visualization of the frame graph in Filament.
+It displays active passes and resource usage, providing insights into the rendering pipeline.</p>
+<h2 id="setup-for-desktop"><a class="header" href="#setup-for-desktop">Setup for Desktop</a></h2>
+<p>When using the easy build script, include the <code>-t</code> argument. For example:</p>
+<pre><code>./build.sh -ft debug gltf_viewer
+</code></pre>
+<p>The <code>t</code> enables a CMake option called <code>FILAMENT_ENABLE_FGVIEWER</code> and the <code>f</code> ensures that CMake gets
+re-run so that the option is honored.</p>
+<p>Next, set an environment variable as follows. In Windows, use <code>set</code> instead of <code>export</code>.</p>
+<pre><code>export FILAMENT_FGVIEWER_PORT=8050
+</code></pre>
+<p>Next, launch any app that links against a debug build of a Filament and point your web browser to
+http://localhost:8050. Skip ahead to <strong>Debugger Usage</strong>.</p>
+<h2 id="setup-for-android"><a class="header" href="#setup-for-android">Setup for Android</a></h2>
+<p>Rebuild Filament for Android after enabling a CMake option called <code>FILAMENT_ENABLE_FGVIEWER</code>. Note that
+CMake is invoked from several places for Android (both gradle and our easy build script), so one
+pragmatic and reliable way of doing this is to simply hack <code>CMakeLists.txt</code> and
+<code>filament-android/CMakeLists.txt</code> by unconditionally setting <code>FILAMENT_ENABLE_FGVIEWER</code> to <code>ON</code>.</p>
+<p>After rebuilding Filament with the option enabled, ensure that internet permissions are enabled in
+your app by adding the following into your manifest as a child of the <code>&lt;manifest&gt;</code> element.</p>
+<pre><code>&lt;uses-permission android:name="android.permission.INTERNET" /&gt;
+</code></pre>
+<p>Now launch your app as usual. The Filament Engine sets up a server that is hardcoded to listen to
+port <code>8085</code>. Next, you will need to forward your device's TCP port <code>8085</code> to your host port of choice.
+For example, to forward the fgviewer server on your device to port <code>8085</code> on your host machine, do the
+following:</p>
+<pre><code>adb forward tcp:8085 tcp:8085
+</code></pre>
+<p>This lets you go to http://localhost:8085 in Chrome on your host machine.</p>
+<h2 id="debugger-usage"><a class="header" href="#debugger-usage">Debugger Usage</a></h2>
+<p>After opening the fgviewer page in your browser, you can see the active views are on the left panel.
+Then you can select any of them to see the active passes and resources for that view.</p>
+<p align="center">
+  <img width="600px" src=https://github.com/user-attachments/assets/2d31767f-fc25-4f17-8c14-528fe5c6b698>
+</p>
+<h2 id="architecture-overview"><a class="header" href="#architecture-overview">Architecture Overview</a></h2>
+<p align="center">
+  <img width="450" src=https://github.com/user-attachments/assets/537ebb89-6ad0-4b93-bbeb-207d4fe9ec5a>
+</p>
+<p>The fgviewer library has two parts: a C++ server and a JavaScript client. The C++ server is
+responsible for instancing a <a href="https://github.com/civetweb/civetweb">civetweb</a> context that handles HTTP requests. The
+JavaScript client is a small web app that contains a view into an in-browser database of framegraphs.</p>
+<p>When a new connection is established, the client asks the server for a list of framegraphs
+in order to populate its in-browser database. If the connection is lost (e.g. if the app crashes),
+then the database stays intact and the web app is still functional.</p>
+<h2 id="c-server"><a class="header" href="#c-server">C++ Server</a></h2>
+<p>The civetweb server is wrapped by our <code>DebugServer</code> class, which provides a public interface consisting of
+a few methods invoked by the Filament engine.</p>
+<p>Since each view corresponds to a frame graph, the engine should notify <code>DebugServer</code> of any changes to the views
+on the engine side.</p>
+<ul>
+<li><strong>createView</strong> Notifies the debugger that a new view has been created.</li>
+<li><strong>updateView</strong> Notifies the debugger of updates to an existing view.</li>
+<li><strong>destroyView</strong> Notifies the debugger that a view is being removed.</li>
+</ul>
+<h2 id="javascript-client"><a class="header" href="#javascript-client">JavaScript Client</a></h2>
+<p>The web app is built using LitElement, a lightweight library for creating Web Components. Our goal is to keep the code simple and modern, avoiding frameworks like React or Angular.</p>
+<p>The app presents a view over a pseudo-database, which is essentially a global variable holding a dictionary that maps frame graph ids to objects following the JSON structure described below.</p>
+<h2 id="http-requests"><a class="header" href="#http-requests">HTTP requests</a></h2>
+<p>The server responds to the following GET requests by returning a JSON blob. The <code>{id}</code> in these
+requests is a concept specific to fgviewer (not Filament) which is an 8-digit hex string for identifying frame graphs.</p>
+<hr />
+<p><code>/api/framegraphs</code></p>
+<p>Returns an array containing all framegraphs in an app. Example:</p>
+<pre><code class="language-json">[{
+    "fgid": "00000000",
+    "viewName": "Main View",
+    "passes": [{
+        "name": "shadow pass",
+        "reads": [],
+        "writes": ["0"]
+    }],
+    "resources": [{
+        "id": "0",
+        "name": "shadowmap",
+        "properties": [{"resolution": "256x256"}, {"is_subresource": "false"}]
+    }]
+},
+{
+    "fgid": "00000001",
+    "viewName": "UI view",
+    ...
+}]
+</code></pre>
+<hr />
+<p><code>/api/framegraph?fg={id}</code></p>
+<p>Returns a specific framegraph info. Example:</p>
+<pre><code class="language-json">{
+  "fgid": "00000000",
+  "viewName": "Main View",
+  "passes": [{
+    "name": "shadow pass",
+    "reads": [],
+    "writes": ["0"]
+  }],
+  "resources": [{
+    "id": "0",
+    "name": "shadowmap",
+    "properties": [{"resolution": "256x256"}, {"is_subresource": "false"}]
+  }]
+}
+</code></pre>
+<hr />
+<p><code>/api/status</code></p>
+<p>Returns one of the below:</p>
+<ul>
+<li><code>0</code>: first time connected</li>
+<li><code>1</code>: no-op</li>
+<li><code>{fgid}</code>: the corresponding frame graph has an update
+<ul>
+<li>Then the web view can request for the actual info using the previous api</li>
+</ul>
+</li>
+</ul>
+<p>If the request gets timeout, the web page show disconnected to the user.</p>
+<hr />
+<h2 id="wish-list"><a class="header" href="#wish-list">Wish List</a></h2>
+<ul>
+<li>Display the texture contents on the webview</li>
+</ul>
+
+                    </main>
+
+                    <nav class="nav-wrapper" aria-label="Page navigation">
+                        <!-- Mobile navigation buttons -->
+                            <a rel="prev" href="../dup/bluevk.html" class="mobile-nav-chapters previous" title="Previous chapter" aria-label="Previous chapter" aria-keyshortcuts="Left">
+                                <i class="fa fa-angle-left"></i>
+                            </a>
+
+                            <a rel="next prefetch" href="../dup/filamat.html" class="mobile-nav-chapters next" title="Next chapter" aria-label="Next chapter" aria-keyshortcuts="Right">
+                                <i class="fa fa-angle-right"></i>
+                            </a>
+
+                        <div style="clear: both"></div>
+                    </nav>
+                </div>
+            </div>
+
+            <nav class="nav-wide-wrapper" aria-label="Page navigation">
+                    <a rel="prev" href="../dup/bluevk.html" class="nav-chapters previous" title="Previous chapter" aria-label="Previous chapter" aria-keyshortcuts="Left">
+                        <i class="fa fa-angle-left"></i>
+                    </a>
+
+                    <a rel="next prefetch" href="../dup/filamat.html" class="nav-chapters next" title="Next chapter" aria-label="Next chapter" aria-keyshortcuts="Right">
+                        <i class="fa fa-angle-right"></i>
+                    </a>
+            </nav>
+
+        </div>
+
+
+
+
+        <script>
+            window.playground_copyable = true;
+        </script>
+
+
+        <script src="../elasticlunr.min.js"></script>
+        <script src="../mark.min.js"></script>
+        <script src="../searcher.js"></script>
+
+        <script src="../clipboard.min.js"></script>
+        <script src="../highlight.js"></script>
+        <script src="../book.js"></script>
+
+        <!-- Custom JS scripts -->
+
+
+    </div>
+    </body>
+</html>

docs/dup/filamat.html

@@ -336,7 +336,7 @@ void material(inout MaterialInputs material) {
 
                     <nav class="nav-wrapper" aria-label="Page navigation">
                         <!-- Mobile navigation buttons -->
-                            <a rel="prev" href="../dup/bluevk.html" class="mobile-nav-chapters previous" title="Previous chapter" aria-label="Previous chapter" aria-keyshortcuts="Left">
+                            <a rel="prev" href="../dup/fgviewer.html" class="mobile-nav-chapters previous" title="Previous chapter" aria-label="Previous chapter" aria-keyshortcuts="Left">
                                 <i class="fa fa-angle-left"></i>
                             </a>
 
@@ -350,7 +350,7 @@ void material(inout MaterialInputs material) {
             </div>
 
             <nav class="nav-wide-wrapper" aria-label="Page navigation">
-                    <a rel="prev" href="../dup/bluevk.html" class="nav-chapters previous" title="Previous chapter" aria-label="Previous chapter" aria-keyshortcuts="Left">
+                    <a rel="prev" href="../dup/fgviewer.html" class="nav-chapters previous" title="Previous chapter" aria-label="Previous chapter" aria-keyshortcuts="Left">
                         <i class="fa fa-angle-left"></i>
                     </a>
 

docs/dup/intro.html

@@ -181,7 +181,7 @@ important for <code>matc</code> (material compiler).</p>
 }
 
 dependencies {
-    implementation 'com.google.android.filament:filament-android:1.65.2'
+    implementation 'com.google.android.filament:filament-android:1.66.2'
 }
 </code></pre>
 <p>Here are all the libraries available in the group <code>com.google.android.filament</code>:</p>
@@ -196,7 +196,7 @@ dependencies {
 </div>
 <h3 id="ios"><a class="header" href="#ios">iOS</a></h3>
 <p>iOS projects can use CocoaPods to install the latest release:</p>
-<pre><code class="language-shell">pod 'Filament', '~&gt; 1.65.2'
+<pre><code class="language-shell">pod 'Filament', '~&gt; 1.66.2'
 </code></pre>
 <h2 id="documentation"><a class="header" href="#documentation">Documentation</a></h2>
 <ul>

docs/dup/renderdiff.html

@@ -159,16 +159,16 @@
                 <div id="content" class="content">
                     <main>
                         <h1 id="rendering-difference-test"><a class="header" href="#rendering-difference-test">Rendering Difference Test</a></h1>
-<p>We created a few scripts to run <code>gltf_viewer</code> and produce headless renderings.</p>
+<p>This tool is a collections of scripts to run <code>gltf_viewer</code> and produce headless renderings.</p>
 <p>This is mainly useful for continuous integration where GPUs are generally not available on cloud
 machines. To perform software rasterization, these scripts are centered around <a href="https://docs.mesa3d.org">Mesa</a>'s
 software rasterizers, but nothing bars us from using another rasterizer like <a href="https://github.com/google/swiftshader">SwiftShader</a>.
 Additionally, we should be able to use GPUs where available (though this is more of a future
 work).</p>
 <p>The script <code>render.py</code> contains the core logic for taking input parameters (such as the test
-description file) and then running gltf_viewer to produce the renderings.</p>
+description file) and then running <code>gltf_viewer</code> to produce the renderings.</p>
 <p>In the <code>test</code> directory is a list of test descriptions that are specified in json. Please see
-<code>sample.json</code> to parse the structure.</p>
+<code>sample.json</code> to glean the structure.</p>
 <h2 id="setting-up-python"><a class="header" href="#setting-up-python">Setting up python</a></h2>
 <p>The <code>renderdiff</code> project uses <code>python</code> extensively. To install the dependencies for producing
 renderings, do the following step</p>
@@ -206,11 +206,15 @@ golden repo.</li>
 </code></pre>
 </li>
 </ul>
-<h2 id="filtering-tests"><a class="header" href="#filtering-tests">Filtering Tests</a></h2>
-<p>You can run a subset of the tests by passing the <code>--test_filter</code> flag to <code>local_test.sh</code>. The
-filter supports wildcards (<code>*</code>) to match test names. For example, to run all tests in the
-<code>ClearCoat</code> suite, you can use the following command:</p>
-<pre><code>bash test/renderdiff/local_test.sh --test_filter='ClearCoat.*.*'
+<h2 id="command-line-options"><a class="header" href="#command-line-options">Command-line Options</a></h2>
+<p>You can control the behavior of the test scripts with the following flags passed to <code>local_test.sh</code>:</p>
+<ul>
+<li><code>--test_filter=&lt;filter&gt;</code>: Run a subset of tests. The filter supports wildcards (<code>*</code>) to match test names.</li>
+<li><code>--no_rebuild</code>: Skip rebuilding the <code>gltf_viewer</code> executable.</li>
+<li><code>--num_threads=&lt;number&gt;</code>: Set the number of threads for rendering. If not set, the system's default is used.</li>
+</ul>
+<p>For example, to run all <code>MSAA</code> tests without rebuilding and using 8 threads:</p>
+<pre><code>bash test/renderdiff/local_test.sh --test_filter='MSAA.*.*' --no_rebuild --num_threads=8
 </code></pre>
 <h2 id="update-the-golden-images"><a class="header" href="#update-the-golden-images">Update the golden images</a></h2>
 <p>The golden images are stored in a github repository:
@@ -276,6 +280,13 @@ For example, it could be <code>out/renderdiff/diffs/presubmit</code> for the sta
 </code></pre>
 <p>where <code>[PR #]</code> is the numeric ID of your pull request, and the <code>[github token]</code> is an acess
 token that you (as a github user) needs to generate (<a href="https://docs.github.com/en/authentication/keeping-your-account-and-data-secure/managing-your-personal-access-tokens">reference</a>).</p>
+<p>To see the results of a specific run, you would do the following</p>
+<pre><code>python3 test/renderdiff/src/viewer.py --run_number=[RUN #] --github_token=[github token]
+</code></pre>
+<p>where <code>[RUN #]</code> is the numeric ID of the run. You can find the run number in the URL of the
+GitHub Actions page. For example, in the URL
+<code>https://github.com/google/filament/actions/runs/18023632663/job/51286323708?pr=9264</code>,
+the run number is <code>18023632663</code>.</p>
 
                     </main>
 

docs/notes/asan_ubsan.html

@@ -160,10 +160,15 @@
                     <main>
                         <h1 id="running-with-asanubsan"><a class="header" href="#running-with-asanubsan">Running with ASAN/UBSAN</a></h1>
 <h2 id="enabling"><a class="header" href="#enabling">Enabling</a></h2>
-<p>When building though build.sh, pass the <code>-b</code> flag. This sets the cmake variable
+<p>When building though <code>build.sh</code>, pass the <code>-b</code> flag. This sets the cmake variable
 <code>FILAMENT_ENABLE_ASAN_UBSAN=ON</code> which eventually passes <code>"-fsanitize=address -fsanitize=undefined"</code>
 to all compile and link operations.</p>
-<p>If building through CMake directly, or an IDE like CLion that doesn't use build.sh, instead pass
+<p>It might be desirable to pair the <code>-b</code> with <code>-y release</code>. The <code>-y</code> flag indicates that targets
+in <code>/tools</code> will be built separately from the filament target, and the filament build depends on
+the <code>/tools</code> targets as prebuilt binaries. This separation reduces ASAN/UBSAN build time
+considerably. This option assumes that the user is trying to catch sanitization issues for
+filament and not the tools that are used to build filament.</p>
+<p>If building through CMake directly, or an IDE like CLion that doesn't use <code>build.sh</code>, instead pass
 <code>-DFILAMENT_ENABLE_ASAN_UBSAN=ON</code> to cmake in order to get the same result.</p>
 <h2 id="getting-memory-leak-detection-on-mac"><a class="header" href="#getting-memory-leak-detection-on-mac">Getting memory leak detection on Mac</a></h2>
 <p>Memory leak detection isn't enabled by default on MacOS. There are two issues to address, first is

docs_src/build/checks.py

@@ -77,11 +77,11 @@ def check_has_source_edits(commit_hash, printing=True):
 
 # Returns true in a given TAG is found in the commit msg
 def commit_msg_has_tag(commit_hash, tag, printing=True):
-  res, ret = execute(f'git log --pretty=%B {commit_hash}', cwd=ROOT_DIR)
+  res, ret = execute(f'git log -n1 --pretty=%B {commit_hash}', cwd=ROOT_DIR)
   for l in ret.split('\n'):
     if tag == l.strip():
       if printing:
-        print(f'Found tag={tag} in commit message')
+        print(f'Found tag={tag} in commit={commit_hash}')
       return True
   return False
 

docs_src/build/duplicates.json

@@ -46,6 +46,9 @@
     "libs/matdbg/README.md": {
         "dest": "dup/matdbg.md"
     },
+    "libs/fgviewer/README.md": {
+        "dest": "dup/fgviewer.md"
+    },
     "tools/normal-blending/README.md": {
         "dest": "dup/normal_blending.md"
     },

docs_src/build/requirements.txt

@@ -0,0 +1,15 @@
+attrs==25.4.0
+certifi==2025.10.5
+h11==0.16.0
+idna==3.11
+outcome==1.3.0.post0
+PySocks==1.7.1
+selenium==4.37.0
+sniffio==1.3.1
+sortedcontainers==2.4.0
+trio==0.31.0
+trio-websocket==0.12.2
+typing_extensions==4.15.0
+urllib3==2.5.0
+websocket-client==1.9.0
+wsproto==1.2.0

docs_src/build/run.py

@@ -140,6 +140,8 @@ if __name__ == "__main__":
   res, err = execute('mdbook build', cwd=MDBOOK_DIR)
   assert res == 0, f"failed to execute `mdbook`. return-code={res} err=\"{err}\""
 
-  shutil.copytree(RAW_COPIES_DIR, BOOK_OUPUT_DIR, dirs_exist_ok=True)
+  RAW_IGNORES = shutil.ignore_patterns('update_remote_ui.sh')
+
+  shutil.copytree(RAW_COPIES_DIR, BOOK_OUPUT_DIR, ignore=RAW_IGNORES, dirs_exist_ok=True)
   shutil.copy(os.path.join(MARKDEEP_DIR, FILAMENT_MD), BOOK_OUPUT_DIR)
   shutil.copy(os.path.join(MARKDEEP_DIR, MATERIALS_MD), BOOK_OUPUT_DIR)

docs_src/src_mdbook/src/SUMMARY.md

@@ -32,6 +32,7 @@
   - [Libraries](./notes/libs.md)
     - [bluegl](./dup/bluegl.md)
     - [bluevk](./dup/bluevk.md)
+    - [fgviewer](./dup/fgviewer.md)
     - [filamat](./dup/filamat.md)
     - [gltfio](./dup/gltfio.md)
     - [iblprefilter](./dup/iblprefilter.md)

docs_src/src_mdbook/src/build/maven_release.md

@@ -9,8 +9,8 @@ To publish under the `com.google.android` namespace, you'll also need to email
 `central-support@sonatype.com` with your account information to request access.
 
 Then, generate a user token through the Sonatype website. Navigate to
-[https://central.sonatype.com/account](https://central.sonatype.com/account) and select **Generate
-User Token**.
+[https://central.sonatype.com/usertoken](https://central.sonatype.com/usertoken)
+and select **Generate User Token**.
 
 Finally, add the generated token credentials to `~/.gradle/gradle.properties`. (Note: these are
 different from the credentials used to log into your Sonatype account):

docs_src/src_mdbook/src/notes/asan_ubsan.md

@@ -2,11 +2,17 @@
 
 ## Enabling
 
-When building though build.sh, pass the `-b` flag. This sets the cmake variable
+When building though `build.sh`, pass the `-b` flag. This sets the cmake variable
 `FILAMENT_ENABLE_ASAN_UBSAN=ON` which eventually passes `"-fsanitize=address -fsanitize=undefined"`
 to all compile and link operations.
 
-If building through CMake directly, or an IDE like CLion that doesn't use build.sh, instead pass
+It might be desirable to pair the `-b` with `-y release`. The `-y` flag indicates that targets
+in `/tools` will be built separately from the filament target, and the filament build depends on
+the `/tools` targets as prebuilt binaries. This separation reduces ASAN/UBSAN build time
+considerably. This option assumes that the user is trying to catch sanitization issues for
+filament and not the tools that are used to build filament.
+
+If building through CMake directly, or an IDE like CLion that doesn't use `build.sh`, instead pass
 `-DFILAMENT_ENABLE_ASAN_UBSAN=ON` to cmake in order to get the same result.
 
 ## Getting memory leak detection on Mac

docs_src/src_raw/remote/update.sh

@@ -1,17 +0,0 @@
-#!/bin/bash
-
-pushd "$(dirname "$0")" > /dev/null
-
-curl -OL https://nightly.link/google/filament/workflows/web-continuous/main/filament-web.zip
-unzip -q filament-web.zip
-tar -xvzf filament-release-web.tgz
-rm filament-release-web.tgz
-rm filament-web.zip
-rm filament.d.ts
-cp ../../web/samples/remote.html index.html
-
-popd
-
-git status
-echo ""
-echo "All done! Next, make a git commit that updates docs/remote."

docs_src/src_raw/remote/update_remote_ui.sh

@@ -8,10 +8,10 @@ tar -xvzf filament-release-web.tgz
 rm filament-release-web.tgz
 rm filament-web.zip
 rm filament.d.ts
-cp ../../web/samples/remote.html index.html
+cp ../../../web/samples/remote.html index.html
 
 popd
 
 git status
 echo ""
-echo "All done! Next, make a git commit that updates docs/remote."
+echo "All done! Next, commit the changed files"

filament/CMakeLists.txt

@@ -117,6 +117,7 @@ set(SRCS
         src/components/LightManager.cpp
         src/components/RenderableManager.cpp
         src/components/TransformManager.cpp
+        src/details/BufferAllocator.cpp
         src/details/BufferObject.cpp
         src/details/Camera.cpp
         src/details/ColorGrading.cpp
@@ -138,6 +139,7 @@ set(SRCS
         src/details/SwapChain.cpp
         src/details/Sync.cpp
         src/details/Texture.cpp
+        src/details/UboManager.cpp
         src/details/VertexBuffer.cpp
         src/details/View.cpp
         src/ds/PerViewDescriptorSetUtils.cpp
@@ -196,6 +198,7 @@ set(PRIVATE_HDRS
         src/components/LightManager.h
         src/components/RenderableManager.h
         src/components/TransformManager.h
+        src/details/BufferAllocator.h
         src/details/BufferObject.h
         src/details/Camera.h
         src/details/ColorGrading.h
@@ -216,6 +219,7 @@ set(PRIVATE_HDRS
         src/details/Stream.h
         src/details/SwapChain.h
         src/details/Texture.h
+        src/details/UboManager.h
         src/details/VertexBuffer.h
         src/details/View.h
         src/downcast.h
@@ -249,9 +253,10 @@ set(PRIVATE_HDRS
 set(MATERIAL_SRCS
         src/materials/antiAliasing/fxaa/fxaa.mat
         src/materials/antiAliasing/taa/taa.mat
+        src/materials/blitArray.mat
         src/materials/blitDepth.mat
         src/materials/blitLow.mat
-        src/materials/blitArray.mat
+        src/materials/clearDepth.mat
         src/materials/bloom/bloomDownsample.mat
         src/materials/bloom/bloomDownsample2x.mat
         src/materials/bloom/bloomDownsample9.mat
@@ -360,7 +365,7 @@ add_definitions(
 # Generate all .filamat: default material, skyboxes, and post-process
 # ==================================================================================================
 
-if (CMAKE_CROSSCOMPILING)
+if (CMAKE_CROSSCOMPILING OR FILAMENT_IMPORT_PREBUILT_EXECUTABLES)
     include(${IMPORT_EXECUTABLES})
 endif()
 
@@ -705,6 +710,13 @@ if (MSVC)
 elseif(WEBGL)
     # Avoid strict-vtable-pointers here, it is broken in WebAssembly.
     set(OPTIMIZATION_FLAGS -fvisibility-inlines-hidden)
+elseif(FILAMENT_USING_GCC)
+    set(OPTIMIZATION_FLAGS
+        -ffast-math
+        -fno-finite-math-only
+        -ffp-contract=fast
+        -fvisibility-inlines-hidden
+    )
 else()
     set(OPTIMIZATION_FLAGS
         -ffast-math
@@ -726,6 +738,18 @@ set(LINUX_COMPILER_FLAGS
 
 if (MSVC)
     set(FILAMENT_WARNINGS /W3)
+elseif (FILAMENT_USING_GCC)
+    # GCC is not officially supported, so use a weaker set of warnings (incl. not using -Werror).
+    set(FILAMENT_WARNINGS
+            -Wall -Wextra-semi -Wundef
+            -Wno-unused-parameter -Wno-missing-field-initializers
+            -Wno-unused-but-set-variable -Wno-unused-variable -Wno-unused-function
+            -Wnon-virtual-dtor -Wimplicit-fallthrough
+            -Wno-strict-aliasing
+            -Wno-changes-meaning -Wno-return-type
+            -Wno-invalid-constexpr -Wno-parentheses
+            -Wno-sign-compare -Wno-deprecated-declarations
+    )
 else()
     set(FILAMENT_WARNINGS
             -Wall -Wextra -Wno-unused-parameter -Wno-missing-field-initializers

filament/README.md

@@ -92,7 +92,7 @@ Copy your platform's Makefile below into a `Makefile` inside the same directory.
 ### Linux
 
 ```make
-FILAMENT_LIBS=-lfilament -lbackend -lbluegl -lbluevk -lfilabridge -lfilaflat -lutils -lgeometry -lsmol-v -lvkshaders -libl -labseil
+FILAMENT_LIBS=-lfilament -lbackend -lbluegl -lbluevk -lfilabridge -lfilaflat -lutils -lgeometry -lsmol-v -libl -labseil
 CC=clang++
 
 main: main.o
@@ -110,7 +110,7 @@ clean:
 ### macOS
 
 ```make
-FILAMENT_LIBS=-lfilament -lbackend -lbluegl -lbluevk -lfilabridge -lfilaflat -lutils -lgeometry -lsmol-v -lvkshaders -libl -labseil
+FILAMENT_LIBS=-lfilament -lbackend -lbluegl -lbluevk -lfilabridge -lfilaflat -lutils -lgeometry -lsmol-v -libl -labseil
 FRAMEWORKS=-framework Cocoa -framework Metal -framework CoreVideo
 CC=clang++
 ARCH ?= $(shell uname -m)
@@ -140,7 +140,7 @@ used to change the run-time library version.
 
 ```make
 FILAMENT_LIBS=filament.lib backend.lib bluegl.lib bluevk.lib filabridge.lib filaflat.lib \
-              utils.lib geometry.lib smol-v.lib ibl.lib vkshaders.lib abseil.lib
+              utils.lib geometry.lib smol-v.lib ibl.lib abseil.lib
 CC=cl.exe
 
 main.exe: main.obj

filament/backend/CMakeLists.txt

@@ -104,6 +104,10 @@ if (FILAMENT_SUPPORTS_OPENGL AND NOT FILAMENT_USE_EXTERNAL_GLES3)
         list(APPEND SRCS src/VirtualMachineEnv.cpp)
     endif ()
     if (ANDROID)
+        list(APPEND SRCS src/AndroidNdk.cpp)
+        list(APPEND SRCS src/AndroidNativeWindow.cpp)
+        list(APPEND SRCS src/AndroidSwapChainHelper.cpp)
+        list(APPEND SRCS src/AndroidFrameCallback.cpp)
         list(APPEND SRCS src/opengl/platforms/ExternalStreamManagerAndroid.cpp)
         list(APPEND SRCS src/opengl/platforms/PlatformEGLAndroid.cpp)
     elseif (IOS)
@@ -248,10 +252,21 @@ if (FILAMENT_SUPPORTS_VULKAN)
             src/vulkan/utils/Spirv.h
             src/vulkan/utils/StaticVector.h
     )
-    if (LINUX OR WIN32)
-        list(APPEND SRCS src/vulkan/platform/VulkanPlatformLinuxWindows.cpp)
+    if (LINUX)
+        list(APPEND SRCS
+            src/vulkan/platform/VulkanPlatformLinux.cpp
+            include/backend/platforms/VulkanPlatformLinux.h
+        )
+    elseif (WIN32)
+        list(APPEND SRCS
+            include/backend/platforms/VulkanPlatformWindows.h
+            src/vulkan/platform/VulkanPlatformWindows.cpp
+        )
     elseif (APPLE OR IOS)
-        list(APPEND SRCS src/vulkan/platform/VulkanPlatformApple.mm)
+        list(APPEND SRCS
+            include/backend/platforms/VulkanPlatformApple.h
+            src/vulkan/platform/VulkanPlatformApple.mm
+        )
     elseif (ANDROID)
         list(APPEND SRCS
             include/backend/platforms/VulkanPlatformAndroid.h
@@ -294,6 +309,8 @@ if (FILAMENT_SUPPORTS_WEBGPU)
             src/webgpu/WebGPUPipelineLayoutCache.h
             src/webgpu/WebGPUProgram.cpp
             src/webgpu/WebGPUProgram.h
+            src/webgpu/WebGPUQueueManager.cpp
+            src/webgpu/WebGPUQueueManager.h
             src/webgpu/WebGPURenderPassMipmapGenerator.cpp
             src/webgpu/WebGPURenderPassMipmapGenerator.h
             src/webgpu/WebGPURenderPrimitive.h
@@ -365,46 +382,6 @@ endif()
 add_library(${TARGET}_headers INTERFACE)
 target_include_directories(${TARGET}_headers INTERFACE ${PUBLIC_HDR_DIR})
 
-# ==================================================================================================
-# Build SPIRV snippets used by the Vulkan backend.
-# ==================================================================================================
-
-set(VKSHADERS_DIR  "${CMAKE_CURRENT_BINARY_DIR}/generated/vkshaders")
-
-file(MAKE_DIRECTORY ${VKSHADERS_DIR})
-
-get_resgen_vars(${VKSHADERS_DIR} vkshaders)
-
-set(VKSHADER_BINS)
-function(build_vkshader SOURCE TARGET_PATH)
-    set(SOURCE_PATH "${CMAKE_CURRENT_SOURCE_DIR}/src/vulkan/${SOURCE}")
-    set(VKSHADER_BINS ${VKSHADER_BINS} ${TARGET_PATH} PARENT_SCOPE)
-    add_custom_command(
-            OUTPUT ${TARGET_PATH}
-            COMMAND matc --raw -o ${TARGET_PATH} ${SOURCE_PATH}
-            MAIN_DEPENDENCY ${SOURCE_PATH}
-            DEPENDS matc ${SOURCE_PATH}
-            COMMENT "Building SPIR-V")
-endfunction()
-build_vkshader("BlitDepth.vs" "BlitDepthVs.spv")
-build_vkshader("BlitDepth.fs" "BlitDepthFs.spv")
-
-add_custom_command(
-        OUTPUT ${RESGEN_OUTPUTS}
-        COMMAND resgen ${RESGEN_FLAGS} ${VKSHADER_BINS}
-        DEPENDS resgen ${VKSHADER_BINS}
-        COMMENT "Aggregating compiled VK shaders")
-
-if (DEFINED RESGEN_SOURCE_FLAGS)
-    set_source_files_properties(${RESGEN_SOURCE} PROPERTIES COMPILE_FLAGS ${RESGEN_SOURCE_FLAGS})
-endif()
-
-set(DUMMY_SRC "${VKSHADERS_DIR}/dummy.c")
-add_custom_command(OUTPUT ${DUMMY_SRC} COMMAND echo "//" > ${DUMMY_SRC})
-
-add_library(vkshaders STATIC ${DUMMY_SRC} ${RESGEN_SOURCE})
-set_target_properties(vkshaders PROPERTIES FOLDER Filament/Generated)
-
 # ==================================================================================================
 # Dependencies
 # ==================================================================================================
@@ -438,7 +415,7 @@ if(FILAMENT_SUPPORTS_OPENGL AND NOT IOS AND NOT ANDROID AND NOT WEBGL)
 endif()
 
 if (FILAMENT_SUPPORTS_VULKAN)
-    target_link_libraries(${TARGET} PUBLIC bluevk vkmemalloc vkshaders smol-v)
+    target_link_libraries(${TARGET} PUBLIC bluevk vkmemalloc smol-v)
     target_link_libraries(${TARGET} PRIVATE SPIRV-Headers)
 endif()
 
@@ -467,6 +444,13 @@ if (MSVC)
 elseif(WEBGL)
     # Avoid strict-vtable-pointers here, it is broken in WebAssembly.
     set(OPTIMIZATION_FLAGS -fvisibility-inlines-hidden)
+elseif(FILAMENT_USING_GCC)
+    set(OPTIMIZATION_FLAGS
+        -ffast-math
+        -fno-finite-math-only
+        -ffp-contract=fast
+        -fvisibility-inlines-hidden
+    )
 else()
     set(OPTIMIZATION_FLAGS
         -ffast-math
@@ -493,6 +477,13 @@ endif()
 
 if (MSVC)
     set(FILAMENT_WARNINGS /W3)
+elseif (FILAMENT_USING_GCC)
+    # GCC is not officially supported, so use a weaker set of warnings (incl. not using -Werror)
+    set(FILAMENT_WARNINGS
+            -Wall -Wno-unused-parameter -Wno-missing-field-initializers
+            -Wdeprecated -Wnon-virtual-dtor -Wno-strict-aliasing
+            -Wno-invalid-constexpr -Wno-parentheses -Wno-unused-variable
+    )
 else()
     set(FILAMENT_WARNINGS
             -Wall -Wextra -Wno-unused-parameter -Wno-missing-field-initializers
@@ -543,7 +534,7 @@ endif()
 # ==================================================================================================
 set(INSTALL_TYPE ARCHIVE)
 install(TARGETS ${TARGET} ${INSTALL_TYPE} DESTINATION lib/${DIST_DIR})
-install(TARGETS vkshaders ${INSTALL_TYPE} DESTINATION lib/${DIST_DIR})
+install(TARGETS ${INSTALL_TYPE} DESTINATION lib/${DIST_DIR})
 install(DIRECTORY ${PUBLIC_HDR_DIR}/backend DESTINATION include)
 
 if (FILAMENT_SUPPORTS_WEBGPU)
@@ -574,6 +565,7 @@ if (APPLE OR LINUX)
         test/test_BufferUpdates.cpp
         test/test_Callbacks.cpp
         test/test_MemoryMappedBuffer.cpp
+        test/test_MsaaSwapChain.cpp
         test/test_MRT.cpp
         test/test_PushConstants.cpp
         test/test_LoadImage.cpp

filament/backend/include/backend/DriverEnums.h

@@ -713,6 +713,12 @@ enum class Precision : uint8_t {
     DEFAULT
 };
 
+union ConstantValue {
+    int32_t i;
+    float f;
+    bool b;
+};
+
 /**
  * Shader compiler priority queue
  *
@@ -1675,7 +1681,7 @@ static_assert(sizeof(StencilState::StencilOperations) == 5u,
 static_assert(sizeof(StencilState) == 12u,
         "StencilState size not what was intended");
 
-using FrameScheduledCallback = utils::Invocable<void(backend::PresentCallable)>;
+using FrameScheduledCallback = utils::Invocable<void(PresentCallable)>;
 
 enum class Workaround : uint16_t {
     // The EASU pass must split because shader compiler flattens early-exit branch
@@ -1697,9 +1703,15 @@ enum class Workaround : uint16_t {
     // prevents these stutters by not precaching depth variants of the default material for those
     // particular browsers.
     DISABLE_DEPTH_PRECACHE_FOR_DEFAULT_MATERIAL,
+    // Emulate an sRGB swapchain in shader code.
+    EMULATE_SRGB_SWAPCHAIN,
 };
 
-using StereoscopicType = backend::Platform::StereoscopicType;
+using StereoscopicType = Platform::StereoscopicType;
+
+using FrameTimestamps = Platform::FrameTimestamps;
+
+using CompositorTiming = Platform::CompositorTiming;
 
 } // namespace filament::backend
 

filament/backend/include/backend/Platform.h

@@ -91,6 +91,113 @@ public:
 
     using ExternalImageHandleRef = ExternalImageHandle const&;
 
+    struct CompositorTiming {
+        /** duration in nanosecond since epoch of std::steady_clock */
+        using time_point_ns = int64_t;
+        /** duration in nanosecond on the std::steady_clock */
+        using duration_ns = int64_t;
+        static constexpr time_point_ns INVALID = -1;    //!< value not supported
+        /**
+         * The timestamp [ns] since epoch of the next time the compositor will begin composition.
+         * This is effectively the deadline for when the compositor must receive a newly queued
+         * frame.
+         */
+        time_point_ns compositeDeadline;
+
+        /**
+         * The time delta [ns] between subsequent composition events.
+         */
+        duration_ns compositeInterval;
+
+        /**
+         * The time delta [ns] between the start of composition and the expected present time of
+         * that composition. This can be used to estimate the latency of the actual present time.
+         */
+        duration_ns compositeToPresentLatency;
+
+        /**
+         * The timestamp [ns] since epoch of the system's expected presentation time.
+         * INVALID if not supported.
+         */
+        time_point_ns expectedPresentTime;
+
+        /**
+         * The timestamp [ns] since epoch of the current frame's start (i.e. vsync)
+         * INVALID if not supported.
+         */
+        time_point_ns frameTime;
+
+        /**
+         * The timestamp [ns] since epoch of the current frame's deadline
+         * INVALID if not supported.
+         */
+        time_point_ns frameTimelineDeadline;
+    };
+
+    struct FrameTimestamps {
+        /** duration in nanosecond since epoch of std::steady_clock */
+        using time_point_ns = int64_t;
+        static constexpr time_point_ns INVALID = -1;    //!< value not supported
+        static constexpr time_point_ns PENDING = -2;    //!< value not yet available
+
+        /**
+         * The time the application requested this frame be presented.
+         * If the application does not request a presentation time explicitly,
+         * this will correspond to buffer's queue time.
+         */
+        time_point_ns requestedPresentTime;
+
+        /**
+         * The time when all the application's rendering to the surface was completed.
+         */
+        time_point_ns acquireTime;
+
+        /**
+         * The time when the compositor selected this frame as the one to use for the next
+         * composition. This is the earliest indication that the frame was submitted in time.
+         */
+        time_point_ns latchTime;
+
+        /**
+         * The first time at which the compositor began preparing composition for this frame.
+         * Zero if composition was handled by the display and the compositor didn't do any
+         * rendering.
+         */
+        time_point_ns firstCompositionStartTime;
+
+        /**
+         * The last time at which the compositor began preparing composition for this frame, for
+         * frames composited more than once. Zero if composition was handled by the display and the
+         * compositor didn't do any rendering.
+         */
+        time_point_ns lastCompositionStartTime;
+
+        /**
+         * The time at which the compositor's rendering work for this frame finished. This will be
+         * INVALID if composition was handled by the display and the compositor didn't do any
+         * rendering.
+         */
+        time_point_ns gpuCompositionDoneTime;
+
+        /**
+         * The time at which this frame started to scan out to the physical display.
+         */
+        time_point_ns displayPresentTime;
+
+        /**
+         * The time when the buffer became available for reuse as a buffer the client can target
+         * without blocking. This is generally the point when all read commands of the buffer have
+         * been submitted, but not necessarily completed.
+         */
+        time_point_ns dequeueReadyTime;
+
+        /**
+         * The time at which all reads for the purpose of display/composition were completed for
+         * this frame.
+         */
+        time_point_ns releaseTime;
+    };
+
     /**
      * The type of technique for stereoscopic rendering. (Note that the materials used will need to
      * be compatible with the chosen technique.)
@@ -236,7 +343,7 @@ public:
      * @return nullptr on failure, or a pointer to the newly created driver.
      */
     virtual Driver* UTILS_NULLABLE createDriver(void* UTILS_NULLABLE sharedContext,
-            const DriverConfig& driverConfig) noexcept = 0;
+            const DriverConfig& driverConfig) = 0;
 
     /**
      * Processes the platform's event queue when called from its primary event-handling thread.
@@ -247,6 +354,65 @@ public:
      */
     virtual bool pumpEvents() noexcept;
 
+    // --------------------------------------------------------------------------------------------
+    // Swapchain timing APIs
+
+    /**
+     * Whether this platform supports compositor timing querying.
+     *
+     * @return true if this Platform supports compositor timings, false otherwise [default]
+     * @see queryCompositorTiming()
+     * @see setPresentFrameId()
+     * @see queryFrameTimestamps()
+     */
+    virtual bool isCompositorTimingSupported() const noexcept;
+
+    /**
+     * If compositor timing is supported, fills the provided CompositorTiming structure
+     * with timing information form the compositor the swapchain's native window is using.
+     * The swapchain'snative window must be valid (i.e. not a headless swapchain).
+     * @param swapchain to query the compositor timing from
+     * @return true on success, false otherwise (e.g. if not supported)
+     * @see isCompositorTimingSupported()
+     */
+    virtual bool queryCompositorTiming(SwapChain const* UTILS_NONNULL swapchain,
+            CompositorTiming* UTILS_NONNULL outCompositorTiming) const noexcept;
+
+    /**
+     * Associate a generic frameId which must be monotonically increasing (albeit not strictly) with
+     * the next frame to be presented on the specified swapchain.
+     *
+     * This must be called from the backend thread.
+     *
+     * @param swapchain
+     * @param frameId
+     * @return true on success, false otherwise
+     * @see isCompositorTimingSupported()
+     * @see queryFrameTimestamps()
+     */
+    virtual bool setPresentFrameId(SwapChain const* UTILS_NONNULL swapchain,
+            uint64_t frameId) noexcept;
+
+    /**
+     * If compositor timing is supported, fills the provided FrameTimestamps structure
+     * with timing information of a given frame, identified by the frame id, of the specified
+     * swapchain. The system only keeps a limited history of frames timings.
+     *
+     * This API is thread safe and can be called from any thread.
+     *
+     * @param swapchain swapchain to query the timestamps of
+     * @param frameId frame we're interested it
+     * @param outFrameTimestamps output structure receiving the timestamps
+     * @return true if successful, false otherwise
+     * @see isCompositorTimingSupported()
+     * @see setPresentFrameId()
+     */
+    virtual bool queryFrameTimestamps(SwapChain const* UTILS_NONNULL swapchain,
+            uint64_t frameId, FrameTimestamps* UTILS_NONNULL outFrameTimestamps) const noexcept;
+
+    // --------------------------------------------------------------------------------------------
+    // Caching APIs
+
     /**
      * InsertBlobFunc is an Invocable to an application-provided function that a
      * backend implementation may use to insert a key/value pair into the
@@ -339,6 +505,9 @@ public:
     size_t retrieveBlob(const void* UTILS_NONNULL key, size_t keySize,
             void* UTILS_NONNULL value, size_t valueSize);
 
+    // --------------------------------------------------------------------------------------------
+    // Debugging APIs
+
     using DebugUpdateStatFunc = utils::Invocable<void(const char* UTILS_NONNULL key, uint64_t value)>;
 
     /**

filament/backend/include/backend/Program.h

@@ -50,11 +50,7 @@ public:
         descriptor_binding_t binding;
     };
 
-    struct SpecializationConstant {
-        using Type = std::variant<int32_t, float, bool>;
-        uint32_t id;    // id set in glsl
-        Type value;     // value and type
-    };
+    using SpecializationConstant = std::variant<int32_t, float, bool>;
 
     struct Uniform { // For ES2 support
         utils::CString name;    // full qualified name of the uniform field
@@ -118,7 +114,7 @@ public:
     Program& multiview(bool multiview) noexcept;
 
     // For ES2 support only...
-    Program& uniforms(uint32_t index, utils::CString name, UniformInfo uniforms) noexcept;
+    Program& uniforms(uint32_t index, utils::CString name, UniformInfo uniforms);
     Program& attributes(AttributesInfo attributes) noexcept;
 
     //

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

@@ -112,7 +112,7 @@ public:
      *
      */
     virtual SwapChain* UTILS_NULLABLE createSwapChain(
-            void* UTILS_NULLABLE nativeWindow, uint64_t flags) noexcept = 0;
+            void* UTILS_NULLABLE nativeWindow, uint64_t flags) = 0;
 
     /**
      * Called by the driver create a headless SwapChain.
@@ -126,7 +126,7 @@ public:
      *       A void* might be enough.
      */
     virtual SwapChain* UTILS_NULLABLE createSwapChain(
-            uint32_t width, uint32_t height, uint64_t flags) noexcept = 0;
+            uint32_t width, uint32_t height, uint64_t flags) = 0;
 
     /**
      * Called by the driver to destroys the SwapChain
@@ -430,7 +430,7 @@ public:
     virtual bool isExtraContextSupported() const noexcept;
 
     /**
-     * Creates an OpenGL context with the same configuration than the main context and makes it
+     * Creates an OpenGL context with the same configuration as the main context and makes it
      * current to the current thread. Must not be called from the main driver thread.
      * createContext() is only supported if isExtraContextSupported() returns true.
      * These additional contexts will be automatically terminated in terminate.
@@ -443,7 +443,7 @@ public:
 
     /**
      * Detach and destroy the current context if any and releases all resources associated to
-     * this thread.
+     * this thread. This must be called from the same thread where createContext() was called.
      */
     virtual void releaseContext() noexcept;
 };

filament/backend/include/backend/platforms/PlatformCocoaGL.h

@@ -40,7 +40,7 @@ protected:
     // Platform Interface
 
     Driver* createDriver(void* sharedContext,
-            const DriverConfig& driverConfig) noexcept override;
+            const DriverConfig& driverConfig) override;
 
     // Currently returns 0
     int getOSVersion() const noexcept override;

filament/backend/include/backend/platforms/PlatformCocoaTouchGL.h

@@ -38,7 +38,7 @@ public:
     // Platform Interface
 
     Driver* createDriver(void* sharedGLContext,
-            const DriverConfig& driverConfig) noexcept override;
+            const DriverConfig& driverConfig) override;
 
     int getOSVersion() const noexcept final { return 0; }
 

filament/backend/include/backend/platforms/PlatformEGL.h

@@ -25,6 +25,7 @@
 #include <EGL/eglext.h>
 #include <EGL/eglplatform.h>
 
+#include <utils/compiler.h>
 #include <utils/Invocable.h>
 
 #include <initializer_list>
@@ -80,7 +81,7 @@ protected:
      * Initializes EGL, creates the OpenGL context and returns a concrete Driver implementation
      * that supports OpenGL/OpenGL ES.
      */
-    Driver* createDriver(void* sharedContext, const DriverConfig& driverConfig) noexcept override;
+    Driver* createDriver(void* sharedContext, const DriverConfig& driverConfig) override;
 
     /**
      * This returns zero. This method can be overridden to return something more useful.
@@ -100,10 +101,6 @@ protected:
     bool isProtectedContextSupported() const noexcept override;
     bool isSRGBSwapChainSupported() const noexcept override;
     bool isMSAASwapChainSupported(uint32_t samples) const 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 isSwapChainProtected(SwapChain* swapChain) noexcept override;
 
     ContextType getCurrentContextType() const noexcept override;
@@ -158,17 +155,9 @@ protected:
         return egl.makeCurrent(context, mEGLDummySurface, mEGLDummySurface);
     }
 
-    // TODO: this should probably use getters instead.
-    EGLDisplay mEGLDisplay = EGL_NO_DISPLAY;
-    EGLContext mEGLContext = EGL_NO_CONTEXT;
-    EGLContext mEGLContextProtected = EGL_NO_CONTEXT;
-    EGLSurface mEGLDummySurface = EGL_NO_SURFACE;
-    ContextType mCurrentContextType = ContextType::NONE;
-    // mEGLConfig is valid only if ext.egl.KHR_no_config_context is false
-    EGLConfig mEGLConfig = EGL_NO_CONFIG_KHR;
-    Config mContextAttribs;
-    std::vector<EGLContext> mAdditionalContexts;
-    bool mMSAA4XSupport = false;
+    EGLDisplay getEglDisplay() const noexcept { return mEGLDisplay; }
+    EGLConfig getEglConfig() const noexcept { return mEGLConfig; }
+    EGLConfig getSuitableConfigForSwapChain(uint64_t flags, bool window, bool pbuffer) const;
 
     // supported extensions detected at runtime
     struct {
@@ -185,7 +174,11 @@ protected:
         } egl;
     } ext;
 
-    struct SwapChainEGL : public Platform::SwapChain {
+    struct SwapChainEGL : public SwapChain {
+        SwapChainEGL(PlatformEGL const& platform, void* nativeWindow, uint64_t flags);
+        SwapChainEGL(PlatformEGL const& platform, uint32_t width, uint32_t height, uint64_t flags);
+        void terminate(PlatformEGL& platform);
+
         EGLSurface sur = EGL_NO_SURFACE;
         Config attribs{};
         EGLNativeWindowType nativeWindow{};
@@ -201,10 +194,25 @@ protected:
         ~ExternalImageEGL() override;
     };
 
-protected:
+private:
+    // prevent derived classes' implementations to call through
+    [[nodiscard]] SwapChain* createSwapChain(void* nativeWindow, uint64_t flags) override;
+    [[nodiscard]] SwapChain* createSwapChain(uint32_t width, uint32_t height, uint64_t flags) override;
+    void destroySwapChain(SwapChain* swapChain) noexcept override;
+
     EGLConfig findSwapChainConfig(uint64_t flags, bool window, bool pbuffer) const;
 
-private:
+    EGLDisplay mEGLDisplay = EGL_NO_DISPLAY;
+    EGLContext mEGLContext = EGL_NO_CONTEXT;
+    EGLContext mEGLContextProtected = EGL_NO_CONTEXT;
+    EGLSurface mEGLDummySurface = EGL_NO_SURFACE;
+    ContextType mCurrentContextType = ContextType::NONE;
+    // mEGLConfig is valid only if ext.egl.KHR_no_config_context is false
+    EGLConfig mEGLConfig = EGL_NO_CONFIG_KHR;
+    Config mContextAttribs;
+    std::vector<EGLContext> mAdditionalContexts;
+    bool mMSAA4XSupport = false;
+
     class EGL {
         EGLDisplay& mEGLDisplay;
         EGLSurface mCurrentDrawSurface = EGL_NO_SURFACE;

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

@@ -17,7 +17,12 @@
 #ifndef TNT_FILAMENT_BACKEND_OPENGL_OPENGL_PLATFORM_EGL_ANDROID_H
 #define TNT_FILAMENT_BACKEND_OPENGL_OPENGL_PLATFORM_EGL_ANDROID_H
 
+#include "AndroidSwapChainHelper.h"
+#include "AndroidFrameCallback.h"
+#include "AndroidNdk.h"
+
 #include <backend/AcquiredImage.h>
+#include <backend/DriverEnums.h>
 #include <backend/Platform.h>
 #include <backend/platforms/OpenGLPlatform.h>
 #include <backend/platforms/PlatformEGL.h>
@@ -25,6 +30,10 @@
 #include <utils/android/PerformanceHintManager.h>
 #include <utils/compiler.h>
 
+#include <math/mat3.h>
+
+#include "AndroidNativeWindow.h"
+
 #include <chrono>
 
 #include <stddef.h>
@@ -38,7 +47,7 @@ class ExternalStreamManagerAndroid;
  * A concrete implementation of OpenGLPlatform and subclass of PlatformEGL that supports
  * EGL on Android. It adds Android streaming functionality to PlatformEGL.
  */
-class PlatformEGLAndroid : public PlatformEGL {
+class PlatformEGLAndroid : public PlatformEGL, public AndroidNdk {
 public:
 
     PlatformEGLAndroid() noexcept;
@@ -67,9 +76,17 @@ public:
      * @return `true` on success, `false` on failure. The default implementation
      *         returns `false`.
      */
-    bool convertSyncToFd(Platform::Sync* sync, int* fd) noexcept;
+    bool convertSyncToFd(Sync* sync, int* fd) noexcept;
 
 protected:
+    struct {
+        struct {
+            bool ANDROID_presentation_time = false;
+            bool ANDROID_get_frame_timestamps = false;
+            bool ANDROID_native_fence_sync = false;
+        } egl;
+    } ext;
+
     // --------------------------------------------------------------------------------------------
     // Platform Interface
 
@@ -80,12 +97,22 @@ protected:
     int getOSVersion() const noexcept override;
 
     Driver* createDriver(void* sharedContext,
-            const Platform::DriverConfig& driverConfig) noexcept override;
+            const DriverConfig& driverConfig) override;
+
+    bool isCompositorTimingSupported() const noexcept override;
+
+    bool queryCompositorTiming(SwapChain const* swapchain,
+            CompositorTiming* outCompositorTiming) const noexcept override;
+
+    bool setPresentFrameId(SwapChain const* swapchain, uint64_t frameId) noexcept override;
+
+    bool queryFrameTimestamps(SwapChain const* swapchain, uint64_t frameId,
+            FrameTimestamps* outFrameTimestamps) const noexcept override;
 
     // --------------------------------------------------------------------------------------------
     // OpenGLPlatform Interface
 
-    struct SyncEGLAndroid : public Platform::Sync {
+    struct SyncEGLAndroid : public Sync {
         EGLSyncKHR sync;
     };
 
@@ -106,8 +133,8 @@ protected:
 
     Stream* createStream(void* nativeStream) noexcept override;
     void destroyStream(Stream* stream) noexcept override;
-    Platform::Sync* createSync() noexcept override;
-    void destroySync(Platform::Sync* sync) noexcept override;
+    Sync* createSync() noexcept override;
+    void destroySync(Sync* sync) noexcept override;
     void attach(Stream* stream, intptr_t tname) noexcept override;
     void detach(Stream* stream) noexcept override;
     void updateTexImage(Stream* stream, int64_t* timestamp) noexcept override;
@@ -120,7 +147,7 @@ protected:
      */
     AcquiredImage transformAcquiredImage(AcquiredImage source) noexcept override;
 
-    OpenGLPlatform::ExternalTexture* createExternalImageTexture() noexcept override;
+    ExternalTexture* createExternalImageTexture() noexcept override;
     void destroyExternalImageTexture(ExternalTexture* texture) noexcept override;
 
     struct ExternalImageEGLAndroid : public ExternalImageEGL {
@@ -140,12 +167,32 @@ protected:
     bool setImage(ExternalImageEGLAndroid const* eglExternalImage,
             ExternalTexture* texture) noexcept;
 
-protected:
     bool makeCurrent(ContextType type,
             SwapChain* drawSwapChain,
             SwapChain* readSwapChain) override;
 
+    struct SwapChainEGLAndroid : public SwapChainEGL {
+        SwapChainEGLAndroid(PlatformEGLAndroid const& platform,
+                void* nativeWindow, uint64_t flags);
+        SwapChainEGLAndroid(PlatformEGLAndroid const& platform,
+                uint32_t width, uint32_t height, uint64_t flags);
+        void terminate(PlatformEGLAndroid& platform);
+        bool setPresentFrameId(uint64_t frameId) const noexcept;
+        uint64_t getFrameId(uint64_t frameId) const noexcept;
+    private:
+        AndroidSwapChainHelper mImpl{};
+    };
+
 private:
+    // prevent derived classes' implementations to call through
+    [[nodiscard]] SwapChain* createSwapChain(void* nativeWindow, uint64_t flags) override;
+    [[nodiscard]] SwapChain* createSwapChain(uint32_t width, uint32_t height, uint64_t flags) override;
+    void destroySwapChain(SwapChain* swapChain) noexcept override;
+
+    bool isProducerThrottlingControlSupported() const;
+
+    int32_t setProducerThrottlingEnabled(EGLNativeWindowType nativeWindow, bool enabled) const;
+
     struct InitializeJvmForPerformanceManagerIfNeeded {
         InitializeJvmForPerformanceManagerIfNeeded();
     };
@@ -159,13 +206,14 @@ private:
     InitializeJvmForPerformanceManagerIfNeeded const mInitializeJvmForPerformanceManagerIfNeeded;
     utils::PerformanceHintManager mPerformanceHintManager;
     utils::PerformanceHintManager::Session mPerformanceHintSession;
+    SwapChainEGLAndroid* mCurrentDrawSwapChain{};
 
     using clock = std::chrono::high_resolution_clock;
     clock::time_point mStartTimeOfActualWork;
-
-    void* mNativeWindowLib = nullptr;
-    int32_t (*ANativeWindow_getBuffersDefaultDataSpace)(ANativeWindow* window) = nullptr;
+    AndroidProducerThrottling mProducerThrottling;
     bool mAssertNativeWindowIsValid = false;
+
+    AndroidFrameCallback mAndroidFrameCallback;
 };
 
 } // namespace filament::backend

filament/backend/include/backend/platforms/PlatformEGLHeadless.h

@@ -29,7 +29,7 @@ public:
     PlatformEGLHeadless() noexcept;
 
     Driver* createDriver(void* sharedContext,
-            const Platform::DriverConfig& driverConfig) noexcept override;
+            const Platform::DriverConfig& driverConfig) override;
 
 protected:
     bool isOpenGL() const noexcept override;

filament/backend/include/backend/platforms/PlatformGLX.h

@@ -26,7 +26,10 @@
 
 #include <backend/DriverEnums.h>
 
+#include <shared_mutex>
+#include <thread>
 #include <vector>
+#include <unordered_map>
 
 namespace filament::backend {
 
@@ -39,7 +42,7 @@ protected:
     // Platform Interface
 
     Driver* createDriver(void* sharedGLContext,
-            const DriverConfig& driverConfig) noexcept override;
+            const DriverConfig& driverConfig) override;
 
     int getOSVersion() const noexcept final override { return 0; }
 
@@ -48,6 +51,10 @@ protected:
 
     void terminate() noexcept override;
 
+    bool isExtraContextSupported() const noexcept override;
+    void createContext(bool shared) override;
+    void releaseContext() 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;
@@ -55,11 +62,15 @@ protected:
     void commit(SwapChain* swapChain) noexcept override;
 
 private:
-    Display *mGLXDisplay;
-    GLXContext mGLXContext;
-    GLXFBConfig* mGLXConfig;
+    Display* mGLXDisplay;
+    GLXContext mGLXContext{};
+    GLXFBConfig mGLXConfig{};
     GLXPbuffer mDummySurface;
     std::vector<GLXPbuffer> mPBuffers;
+
+    // Variables for shared contexts
+    std::unordered_map<std::thread::id, GLXContext> mAdditionalContexts;
+    std::shared_mutex mAdditionalContextsLock;
 };
 
 } // namespace filament::backend

filament/backend/include/backend/platforms/PlatformMetal.h

@@ -36,7 +36,7 @@ public:
     PlatformMetal();
     ~PlatformMetal() noexcept override;
 
-    Driver* createDriver(void* sharedContext, const Platform::DriverConfig& driverConfig) noexcept override;
+    Driver* createDriver(void* sharedContext, const Platform::DriverConfig& driverConfig) override;
     int getOSVersion() const noexcept override { return 0; }
 
     /**

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

@@ -43,7 +43,7 @@ protected:
     // --------------------------------------------------------------------------------------------
     // Platform Interface
 
-    Driver* createDriver(void* sharedGLContext, const DriverConfig& driverConfig) noexcept override;
+    Driver* createDriver(void* sharedGLContext, const DriverConfig& driverConfig) override;
 
     int getOSVersion() const noexcept final override { return 0; }
 

filament/backend/include/backend/platforms/PlatformWGL.h

@@ -38,7 +38,7 @@ protected:
     // Platform Interface
 
     Driver* createDriver(void* sharedGLContext,
-            const Platform::DriverConfig& driverConfig) noexcept override;
+            const Platform::DriverConfig& driverConfig) override;
 
     int getOSVersion() const noexcept final override { return 0; }
 
@@ -61,8 +61,12 @@ protected:
     HWND mHWnd = NULL;
     HDC mWhdc = NULL;
     PIXELFORMATDESCRIPTOR mPfd = {};
-    std::vector<HGLRC> mAdditionalContexts;
     std::vector<int> mAttribs;
+
+    // For shared contexts
+    static constexpr int SHARED_CONTEXT_NUM = 1;
+    std::vector<HGLRC> mAdditionalContexts;
+    std::atomic<int> mNextFreeSharedContextIndex{0};
 };
 
 } // namespace filament::backend

filament/backend/include/backend/platforms/PlatformWebGL.h

@@ -34,7 +34,7 @@ protected:
     // Platform Interface
 
     Driver* createDriver(void* sharedGLContext,
-            const Platform::DriverConfig& driverConfig) noexcept override;
+            const Platform::DriverConfig& driverConfig) override;
 
     int getOSVersion() const noexcept override;
 

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

@@ -119,7 +119,7 @@ public:
     ~VulkanPlatform() override;
 
     Driver* createDriver(void* sharedContext,
-            Platform::DriverConfig const& driverConfig) noexcept override;
+            Platform::DriverConfig const& driverConfig) override;
 
     int getOSVersion() const noexcept override {
         return 0;
@@ -437,22 +437,19 @@ protected:
         std::shared_ptr<VulkanCmdFence> fenceStatus;
     };
 
-    virtual ExtensionSet getSwapchainInstanceExtensions() const;
-
     using SurfaceBundle = std::tuple<VkSurfaceKHR, VkExtent2D>;
+    virtual ExtensionSet getSwapchainInstanceExtensions() const = 0;
     virtual SurfaceBundle createVkSurfaceKHR(void* nativeWindow, VkInstance instance,
-            uint64_t flags) const noexcept;
+            uint64_t flags) const noexcept = 0;
 
     virtual VkExternalFenceHandleTypeFlagBits getFenceExportFlags() const noexcept;
 
+    /**
+     * Query if transient attachments are supported by the backend.
+     */
+    bool isTransientAttachmentSupported() const noexcept;
+
 private:
-    // Platform dependent helper methods
-    static ExtensionSet getSwapchainInstanceExtensionsImpl();
-
-    // Platform dependent helper methods
-    static SurfaceBundle createVkSurfaceKHRImpl(void* nativeWindow, VkInstance instance,
-            uint64_t flags) noexcept;
-
     friend struct VulkanPlatformPrivate;
 };
 

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

@@ -17,6 +17,9 @@
 #ifndef TNT_FILAMENT_BACKEND_PLATFORMS_VULKAN_PLATFORM_ANDROID_H
 #define TNT_FILAMENT_BACKEND_PLATFORMS_VULKAN_PLATFORM_ANDROID_H
 
+#include "AndroidFrameCallback.h"
+#include "AndroidNdk.h"
+
 #include <backend/DriverEnums.h>
 #include <backend/platforms/VulkanPlatform.h>
 
@@ -24,7 +27,7 @@
 
 namespace filament::backend {
 
-class VulkanPlatformAndroid : public VulkanPlatform {
+class VulkanPlatformAndroid : public VulkanPlatform, public AndroidNdk {
 public:
     ExternalImageHandle UTILS_PUBLIC createExternalImage(AHardwareBuffer const* buffer,
             bool sRGB) noexcept;
@@ -36,13 +39,17 @@ public:
         TextureUsage usage;  // Texture usage flags
     };
 
+    VulkanPlatformAndroid();
+
+    ~VulkanPlatformAndroid() noexcept override;
+
     ExternalImageDescAndroid UTILS_PUBLIC getExternalImageDesc(
             ExternalImageHandleRef externalImage) const noexcept;
 
-    virtual ExternalImageMetadata extractExternalImageMetadata(
+    ExternalImageMetadata extractExternalImageMetadata(
             ExternalImageHandleRef image) const override;
 
-    virtual ImageData createVkImageFromExternal(ExternalImageHandleRef image) const override;
+    ImageData createVkImageFromExternal(ExternalImageHandleRef image) const override;
 
     /**
      * Converts a sync to an external file descriptor, if possible. Accepts an
@@ -53,25 +60,47 @@ public:
      * @return `true` on success, `false` on failure. The default implementation
      *         returns `false`.
      */
-    bool convertSyncToFd(Platform::Sync* sync, int* fd) const noexcept;
+    bool convertSyncToFd(Sync* sync, int* fd) const noexcept;
+
+    int getOSVersion() const noexcept override;
+
+    void terminate() override;
+
+    Driver* createDriver(void* sharedContext,
+        DriverConfig const& driverConfig) override;
+
+
+    bool isCompositorTimingSupported() const noexcept override;
+
+    bool queryCompositorTiming(SwapChain const* swapchain,
+            CompositorTiming* outCompositorTiming) const noexcept override;
+
+    bool setPresentFrameId(SwapChain const* swapchain, uint64_t frameId) noexcept override;
+
+    bool queryFrameTimestamps(SwapChain const* swapchain, uint64_t frameId,
+            FrameTimestamps* outFrameTimestamps) const noexcept override;
+
 
 protected:
-    virtual ExtensionSet getSwapchainInstanceExtensions() const override;
+    ExtensionSet getSwapchainInstanceExtensions() const override;
 
-    using SurfaceBundle = VulkanPlatform::SurfaceBundle;
-    virtual SurfaceBundle createVkSurfaceKHR(void* nativeWindow, VkInstance instance,
+    using SurfaceBundle = SurfaceBundle;
+    SurfaceBundle createVkSurfaceKHR(void* nativeWindow, VkInstance instance,
             uint64_t flags) const noexcept override;
 
-    virtual VkExternalFenceHandleTypeFlagBits getFenceExportFlags() const noexcept override;
+    VkExternalFenceHandleTypeFlagBits getFenceExportFlags() const noexcept override;
 
 private:
-    struct ExternalImageVulkanAndroid : public Platform::ExternalImage {
+    struct ExternalImageVulkanAndroid : public ExternalImage {
         AHardwareBuffer* aHardwareBuffer = nullptr;
         bool sRGB = false;
 
     protected:
         ~ExternalImageVulkanAndroid() override;
     };
+
+    AndroidFrameCallback mAndroidFrameCallback;
+    int mOSVersion{};
 };
 
 }// namespace filament::backend

filament/backend/include/backend/platforms/VulkanPlatformApple.h

@@ -0,0 +1,33 @@
+/*
+ * Copyright (C) 2025 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef TNT_FILAMENT_BACKEND_PLATFORMS_VULKANPLATFORMAPPLE_H
+#define TNT_FILAMENT_BACKEND_PLATFORMS_VULKANPLATFORMAPPLE_H
+
+#include <backend/platforms/VulkanPlatform.h>
+
+namespace filament::backend {
+
+class VulkanPlatformApple : public VulkanPlatform {
+protected:
+    ExtensionSet getSwapchainInstanceExtensions() const override;
+    SurfaceBundle createVkSurfaceKHR(void* nativeWindow, VkInstance instance,
+            uint64_t flags) const noexcept override;
+};
+
+} // namespace filament::backend
+
+#endif // TNT_FILAMENT_BACKEND_PLATFORMS_VULKANPLATFORMAPPLE_H

filament/backend/include/backend/platforms/VulkanPlatformLinux.h

@@ -0,0 +1,33 @@
+/*
+ * Copyright (C) 2025 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef TNT_FILAMENT_BACKEND_PLATFORMS_VULKANPLATFORMLINUX_H
+#define TNT_FILAMENT_BACKEND_PLATFORMS_VULKANPLATFORMLINUX_H
+
+#include <backend/platforms/VulkanPlatform.h>
+
+namespace filament::backend {
+
+class VulkanPlatformLinux : public VulkanPlatform {
+protected:
+    ExtensionSet getSwapchainInstanceExtensions() const override;
+    SurfaceBundle createVkSurfaceKHR(void* nativeWindow, VkInstance instance,
+            uint64_t flags) const noexcept override;
+};
+
+} // namespace filament::backend
+
+#endif // TNT_FILAMENT_BACKEND_PLATFORMS_VULKANPLATFORMLINUX_H

filament/backend/include/backend/platforms/VulkanPlatformWindows.h

@@ -0,0 +1,33 @@
+/*
+ * Copyright (C) 2023 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_PLATFORMS_VULKANPLATFORMWINDOWS_H
+#define TNT_FILAMENT_BACKEND_PLATFORMS_VULKANPLATFORMWINDOWS_H
+
+#include <backend/platforms/VulkanPlatform.h>
+
+namespace filament::backend {
+
+class VulkanPlatformWindows : public VulkanPlatform {
+protected:
+    ExtensionSet getSwapchainInstanceExtensions() const override;
+    SurfaceBundle createVkSurfaceKHR(void* nativeWindow, VkInstance instance,
+            uint64_t flags) const noexcept override;
+};
+
+} // namespace filament::backend
+
+#endif // TNT_FILAMENT_BACKEND_PLATFORMS_VULKANPLATFORMWINDOWS_H

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

@@ -72,7 +72,7 @@ public:
 
 protected:
     [[nodiscard]] Driver* createDriver(void* sharedContext,
-            const Platform::DriverConfig& driverConfig) noexcept override;
+            const Platform::DriverConfig& driverConfig) override;
 
 private:
     // returns adapter request option variations applicable for the particular