Metal: use atomic for buffer tracking

.clang-format

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

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

@@ -1,53 +1,43 @@
-# 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 }}"
-        HASH="${{ github.event.head_commit.id }}"
-        echo "commit $HASH" >> /tmp/commit_msg.txt
+        echo "commit ${{ github.event.head_commit.id }}" >> /tmp/commit_msg.txt
         echo "Author: ${AUTHOR_NAME}<${AUTHOR_EMAIL}>" >> /tmp/commit_msg.txt
         echo "Date: ${TSTAMP}" >> /tmp/commit_msg.txt
         echo "" >> /tmp/commit_msg.txt
-        echo "$COMMIT_MESSAGE" >> /tmp/commit_msg.txt
-        echo "$HASH" > /tmp/commit_hash.txt
+        echo "${{ github.event.head_commit.message }}" >> /tmp/commit_msg.txt
     - name: Find commit message (PR)
       shell: bash
       id: checkout_code
       if: github.event_name == 'pull_request'
       run: |
-        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
+        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
     - 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"
-        # Get the commit hash
-        echo "hash=$(cat /tmp/commit_hash.txt)" >> "$GITHUB_OUTPUT"
+        echo "----- got commit message ---"
+        cat /tmp/commit_msg.txt
+        echo "----------------------------"
     - name: Cleanup Find commit message (PR)
       shell: bash
       if: github.event_name == 'pull_request'

.github/workflows/android-continuous.yml

@@ -12,7 +12,7 @@ jobs:
     name: build-android
     # We intentially use a larger runner here to enable larger disk space
     # (standard linux runner will fail on disk space and faster build time).
-    runs-on: 'ubuntu-24.04-16core'
+    runs-on: 'ubuntu-24.04-32core'
 
     steps:
       - uses: actions/checkout@v4.1.6

.github/workflows/postsubmit.yml

@@ -23,7 +23,7 @@ jobs:
           GH_TOKEN: ${{ secrets.FILAMENTBOT_TOKEN }}
         run: |
           GOLDEN_BRANCH=$(echo "${{ steps.get_commit_msg.outputs.msg }}" | python3 test/renderdiff/src/commit_msg.py)
-          COMMIT_HASH="${{ steps.get_commit_msg.outputs.hash }}"
+          COMMIT_HASH=$(echo "${{ steps.get_commit_msg.outputs.msg }}" | head -n 1 | sed "s/commit //g")
           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: ${{ secrets.FILAMENTBOT_TOKEN }}
         run: |
           bash docs_src/build/install_mdbook.sh && source ~/.bashrc
-          COMMIT_HASH="${{ steps.get_commit_msg.outputs.hash }}"
+          COMMIT_HASH=$(echo "${{ steps.get_commit_msg.outputs.msg }}" | head -n 1 | sed "s/commit //g")
           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

@@ -26,7 +26,7 @@ jobs:
 
   build-desktop-linux:
     name: build-linux
-    runs-on: 'ubuntu-24.04-16core'
+    runs-on: ubuntu-22.04-16core
     steps:
       - uses: actions/checkout@v4.1.6
         with:
@@ -108,7 +108,8 @@ jobs:
         uses: ./.github/actions/get-commit-msg
       - name: Check for manual edits to /docs
         run: |
-          bash docs_src/build/presubmit_check.sh ${{ steps.get_commit_msg.outputs.hash }}
+          COMMIT_ID=$(echo "${{ steps.get_commit_msg.outputs.msg }}" | head -n 1 | sed "s/commit //g")
+          bash docs_src/build/presubmit_check.sh ${COMMIT_ID}
 
   test-renderdiff:
     name: test-renderdiff
@@ -120,7 +121,7 @@ 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
@@ -131,14 +132,12 @@ 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 "${COMMIT_MESSAGE}" | python3 ${TEST_DIR}/src/commit_msg.py)
+          GOLDEN_BRANCH=$(echo "${{ steps.get_commit_msg.outputs.msg }}" | python3 ${TEST_DIR}/src/commit_msg.py)
           bash ${TEST_DIR}/generate.sh && \
               python3 ${TEST_DIR}/src/golden_manager.py \
                   --branch=${GOLDEN_BRANCH} \
@@ -172,7 +171,7 @@ jobs:
 
   validate-wgsl-webgpu:
     name: validate-wgsl-webgpu
-    runs-on: 'ubuntu-24.04-16core'
+    runs-on: 'ubuntu-24.04-8core'
     steps:
       - uses: actions/checkout@v4.1.6
         with:
@@ -203,23 +202,3 @@ 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

.github/workflows/release.yml

@@ -31,7 +31,7 @@ on:
 jobs:
   build-linux:
     name: build-linux
-    runs-on: 'ubuntu-24.04-16core'
+    runs-on: ubuntu-22.04-32core
     if: github.event_name == 'release' || github.event.inputs.platform == 'desktop'
 
     steps:

.gitignore

@@ -18,9 +18,3 @@ test*.json
 results
 /compile_commands.json
 /.cache
-
-# For /test/renderdiff dependencies
-/mesa
-/gltf
-/filament-assets
-/venv

BUILDING.md

@@ -391,7 +391,7 @@ 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

@@ -56,8 +56,6 @@ 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)
-
 # 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)
@@ -297,10 +295,15 @@ set(TOOLS ${CMAKE_CURRENT_SOURCE_DIR}/tools)
 # ==================================================================================================
 set(MIN_CLANG_VERSION "6.0")
 
-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_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")
     if (CMAKE_CXX_COMPILER_VERSION VERSION_LESS MIN_CLANG_VERSION)
         message(FATAL_ERROR "Detected CXX compiler Clang ${CMAKE_CXX_COMPILER_VERSION} < ${MIN_CLANG_VERSION}")
     endif()
@@ -341,18 +344,14 @@ if (MSVC)
     set(CXX_STANDARD "/std:c++latest")
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${CXX_STANDARD} /W0 /Zc:__cplusplus")
 else()
-    if(FILAMENT_USING_GCC)
-      set(CMAKE_CXX_FLAGS "${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} ${CXX_STANDARD} -fstrict-aliasing -Wno-unknown-pragmas -Wno-unused-function -Wno-deprecated-declarations")
-    endif()
+    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${CXX_STANDARD} -fstrict-aliasing -Wno-unknown-pragmas -Wno-unused-function -Wno-deprecated-declarations")
     if (APPLE)
         set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-nullability-extension")
     endif()
 endif()
 
 if (FILAMENT_USE_EXTERNAL_GLES3)
-    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -DFILAMENT_USE_EXTERNAL_GLES3")
+    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -DUSE_EXTERNAL_GLES3")
 endif()
 
 if (FILAMENT_SUPPORTS_EGL_ON_LINUX)
@@ -366,14 +365,10 @@ endif()
 if (LINUX)
     option(USE_STATIC_LIBCXX "Link against the static runtime libraries." ON)
     if (${USE_STATIC_LIBCXX})
-        if (FILAMENT_USING_GCC)
-            link_libraries("-static-libgcc -static-libstdc++")
-        else ()
-            set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -stdlib=libc++")
-            link_libraries("-static-libgcc -static-libstdc++")
-            link_libraries(libc++.a)
-            link_libraries(libc++abi.a)
-        endif()
+        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()
 
     # Only linux, clang doesn't want to use a shared library that is not PIC.
@@ -398,8 +393,8 @@ 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 (when not using gcc)
-if (UNIX AND CMAKE_GENERATOR STREQUAL "Ninja" AND NOT FILAMENT_USING_GCC)
+# Add colors to ninja builds
+if (UNIX AND CMAKE_GENERATOR STREQUAL "Ninja")
     set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -fcolor-diagnostics")
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fcolor-diagnostics")
 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++) {
 }
 
@@ -73,24 +73,12 @@ src/data.inc
 - `public` class attributes *are not* prefixed
 - class attributes and methods are lower camelcase
 
-```c++
+```
 extern int gGlobalWarming;
 
 class FooBar {
 public:
-    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
-    }
-
+    void methodName();
     int sizeInBytes;
 private:
     int mAttributeName;
@@ -109,7 +97,7 @@ 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
  *
@@ -151,7 +139,7 @@ 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
  *
@@ -195,7 +183,7 @@ 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

@@ -1,10 +1,9 @@
 # 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
-
-- Metal: Add support for the `SwapChain::CONFIG_MSAA_4_SAMPLES` flag.

README.md

@@ -31,7 +31,7 @@ repositories {
 }
 
 dependencies {
-    implementation 'com.google.android.filament:filament-android:1.67.0'
+    implementation 'com.google.android.filament:filament-android:1.65.0'
 }
 ```
 
@@ -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', '~> 1.67.0'
+pod 'Filament', '~> 1.65.0'
 ```
 
 ## Documentation

RELEASE_NOTES.md

@@ -7,33 +7,6 @@ A new header is inserted each time a *tag* is created.
 Instead, if you are authoring a PR for the main branch, add your release note to
 [NEW_RELEASE_NOTES.md](./NEW_RELEASE_NOTES.md).
 
-## v1.67.0
-
-- 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
-
-
-## v1.65.3
-
-
-## v1.65.2
-
-
 ## v1.65.1
 
 - `setFrameScheduledCallback` now works on all backends (frame presentation scheduling is still only

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

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

@@ -279,17 +279,6 @@ 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

@@ -208,19 +208,3 @@ 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/SwapChain.cpp

@@ -28,8 +28,9 @@ Java_com_google_android_filament_SwapChain_nSetFrameCompletedCallback(JNIEnv* en
         jlong nativeSwapChain, jobject handler, jobject runnable) {
     SwapChain* swapChain = (SwapChain*) nativeSwapChain;
     auto* callback = JniCallback::make(env, handler, runnable);
-    swapChain->setFrameCompletedCallback(callback->getHandler(),
-            [callback](SwapChain* swapChain) { JniCallback::postToJavaAndDestroy(callback); });
+    swapChain->setFrameCompletedCallback(nullptr, [callback](SwapChain* swapChain) {
+        JniCallback::postToJavaAndDestroy(callback);
+    });
 }
 
 extern "C" JNIEXPORT jboolean JNICALL
@@ -52,22 +53,3 @@ Java_com_google_android_filament_SwapChain_nIsProtectedContentSupported(
     Engine* engine = (Engine*) nativeEngine;
     return (jboolean)SwapChain::isProtectedContentSupported(*engine);
 }
-
-extern "C" JNIEXPORT void JNICALL
-Java_com_google_android_filament_SwapChain_nSetFrameScheduledCallback(JNIEnv* env, jclass,
-        jlong nativeSwapChain, jobject handler, jobject runnable) {
-    SwapChain* swapChain = (SwapChain*) nativeSwapChain;
-    auto* callback = JniCallback::make(env, handler, runnable);
-    swapChain->setFrameScheduledCallback(callback->getHandler(),
-            [callback](backend::PresentCallable) {
-                // Ignore PresentCallable, which is only meaningful with the Metal backend.
-                JniCallback::postToJavaAndDestroy(callback);
-            });
-}
-
-extern "C" JNIEXPORT jboolean JNICALL
-Java_com_google_android_filament_SwapChain_nIsFrameScheduledCallbackSet(
-        JNIEnv *, jclass, jlong nativeSwapChain) {
-    SwapChain* swapChain = (SwapChain*) nativeSwapChain;
-    return (jboolean)swapChain->isFrameScheduledCallbackSet();
-}

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

@@ -356,7 +356,6 @@ 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;
@@ -555,20 +554,3 @@ 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/Engine.java

@@ -264,8 +264,7 @@ public class Engine {
                     config.disableHandleUseAfterFreeCheck,
                     config.preferredShaderLanguage.ordinal(),
                     config.forceGLES2Context, config.assertNativeWindowIsValid,
-                    config.gpuContextPriority.ordinal(),
-                    config.sharedUboInitialSizeInBytes);
+                    config.gpuContextPriority.ordinal());
             return this;
         }
 
@@ -526,16 +525,6 @@ 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) {
@@ -1540,8 +1529,7 @@ public class Engine {
             boolean disableHandleUseAfterFreeCheck,
             int preferredShaderLanguage,
             boolean forceGLES2Context, boolean assertNativeWindowIsValid,
-            int gpuContextPriority,
-            long sharedUboInitialSizeInBytes);
+            int gpuContextPriority);
     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

@@ -787,21 +787,6 @@ 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.
      *
@@ -1126,5 +1111,4 @@ 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 8 channels.
+         * Set the channel this renderable is associated to. There can be 4 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..7], defaults to 2.
+         * @param channel clamped to the range [0..3], 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 = 7) int channel) {
+        public Builder channel(@IntRange(from = 0, to = 3) 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 = 7) int channel) {
+    public void setChannel(@EntityInstance int i, @IntRange(from = 0, to = 3) int channel) {
         nSetChannel(mNativeObject, i, channel);
     }
 

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

@@ -732,22 +732,6 @@ 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");
@@ -789,7 +773,4 @@ 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/SwapChain.java

@@ -139,78 +139,6 @@ public class SwapChain {
         nSetFrameCompletedCallback(getNativeObject(), handler, callback);
     }
 
-    /**
-     * FrameScheduledCallback is a callback function that notifies an application about the status
-     * of a frame after Filament has finished its processing.
-     *
-     * <p>
-     * The exact timing and semantics of this callback differ depending on the graphics backend in
-     * use.
-     * </p>
-     *
-     * <h3>Metal Backend</h3>
-     * <p>
-     * With the Metal backend, this callback signifies that Filament has completed all CPU-side
-     * processing for a frame and the frame is ready to be scheduled for presentation.
-     * </p>
-     *
-     * <p>
-     * Typically, Filament is responsible for scheduling the frame's presentation to the SwapChain.
-     * If a FrameScheduledCallback is set, however, the application bears the responsibility of
-     * scheduling the frame for presentation by calling the PresentCallable passed to the callback
-     * function. In this mode, Filament will not automatically schedule the frame for presentation.
-     * </p>
-     *
-     * <p>
-     * When using the Metal backend, if your application delays the call to the PresentCallable
-     * (e.g., by invoking it on a separate thread), you must ensure all PresentCallables have been
-     * called before shutting down the Filament Engine. You can guarantee this by calling
-     * Engine.flushAndWait() before Engine.shutdown(). This is necessary to ensure the Engine has
-     * a chance to clean up all memory related to frame presentation.
-     * </p>
-     *
-     * <h3>Other Backends (OpenGL, Vulkan, WebGPU)</h3>
-     * <p>
-     * On other backends, this callback serves as a notification that Filament has completed all
-     * CPU-side processing for a frame. Filament proceeds with its normal presentation logic
-     * automatically, and the PresentCallable passed to the callback is a no-op that can be safely
-     * ignored.
-     * </p>
-     *
-     * <h3>General Behavior</h3>
-     * <p>
-     * A FrameScheduledCallback can be set on an individual SwapChain through
-     * setFrameScheduledCallback. Each SwapChain can have only one callback set per frame. If
-     * setFrameScheduledCallback is called multiple times on the same SwapChain before
-     * Renderer.endFrame(), the most recent call effectively overwrites any previously set callback.
-     * </p>
-     *
-     * <p>
-     * The callback set by setFrameScheduledCallback is "latched" when Renderer.endFrame() is
-     * executed. At this point, the callback is fixed for the frame that was just encoded.
-     * Subsequent calls to setFrameScheduledCallback after endFrame() will apply to the next frame.
-     * </p>
-     *
-     * <p>
-     * Use setFrameScheduledCallback() (with default arguments) to unset the callback.
-     * </p>
-     *
-     * @param handler     A {@link java.util.concurrent.Executor Executor}.
-     * @param callback    The Runnable callback to invoke when frame processing is complete.
-     */
-    public void setFrameScheduledCallback(@NonNull Object handler, @NonNull Runnable callback) {
-        nSetFrameScheduledCallback(getNativeObject(), handler, callback);
-    }
-
-    /**
-     * Returns whether this SwapChain currently has a FrameScheduledCallback set.
-     *
-     * @return true, if the last call to setFrameScheduledCallback set a callback
-     */
-    public boolean isFrameScheduledCallbackSet() {
-        return nIsFrameScheduledCallbackSet(getNativeObject());
-    }
-
     public long getNativeObject() {
         if (mNativeObject == 0) {
             throw new IllegalStateException("Calling method on destroyed SwapChain");
@@ -223,8 +151,6 @@ public class SwapChain {
     }
 
     private static native void nSetFrameCompletedCallback(long nativeSwapChain, Object handler, Runnable callback);
-    private static native void nSetFrameScheduledCallback(long nativeSwapChain, Object handler, Runnable callback);
-    private static native boolean nIsFrameScheduledCallbackSet(long nativeSwapChain);
     private static native boolean nIsSRGBSwapChainSupported(long nativeEngine);
     private static native boolean nIsMSAASwapChainSupported(long nativeEngine, int samples);
     private static native boolean nIsProtectedContentSupported(long nativeEngine);

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

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

@@ -291,25 +291,6 @@ 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.
      *
@@ -1337,8 +1318,6 @@ 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);
@@ -1636,7 +1615,7 @@ 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};
@@ -1677,7 +1656,7 @@ public class View {
          *
          * `fogColorFromIbl` is ignored when skyTexture is specified.
          *
-         * @see #skyColor
+         * @see skyColor
          */
         public boolean fogColorFromIbl = false;
         /**
@@ -1695,7 +1674,7 @@ public class View {
          * In `linearFog` mode mipmap level 0 is always used.
          *
          * @see Texture
-         * @see #fogColorFromIbl
+         * @see fogColorFromIbl
          */
         @Nullable
         public Texture skyColor = null;
@@ -1817,8 +1796,7 @@ public class View {
     /**
      * Structure used to set the precision of the color buffer and related quality settings.
      *
-     * @see #setRenderQuality
-     * @see #getRenderQuality
+     * @see setRenderQuality, getRenderQuality
      */
     public static class RenderQuality {
         /**
@@ -1836,7 +1814,7 @@ 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 {
@@ -1988,7 +1966,7 @@ public class View {
 
     /**
      * Options for Multi-Sample Anti-aliasing (MSAA)
-     * @see #setMultiSampleAntiAliasingOptions
+     * @see setMultiSampleAntiAliasingOptions()
      */
     public static class MultiSampleAntiAliasingOptions {
         /**
@@ -2018,7 +1996,7 @@ 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 {
@@ -2120,7 +2098,7 @@ public class View {
 
     /**
      * Options for Screen-space Reflections.
-     * @see #setScreenSpaceReflectionsOptions
+     * @see setScreenSpaceReflectionsOptions()
      */
     public static class ScreenSpaceReflectionsOptions {
         /**
@@ -2154,9 +2132,7 @@ public class View {
 
     /**
      * List of available post-processing anti-aliasing techniques.
-     * @see #setAntiAliasing
-     * @see #getAntiAliasing
-     * @see #setSampleCount
+     * @see setAntiAliasing, getAntiAliasing, setSampleCount
      */
     public enum AntiAliasing {
         /**
@@ -2185,7 +2161,7 @@ public class View {
 
     /**
      * List of available shadow mapping techniques.
-     * @see #setShadowType
+     * @see setShadowType
      */
     public enum ShadowType {
         /**
@@ -2209,7 +2185,7 @@ 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 {
@@ -2250,7 +2226,7 @@ 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/gradle.properties

@@ -1,5 +1,5 @@
 GROUP=com.google.android.filament
-VERSION_NAME=1.67.0
+VERSION_NAME=1.65.0
 
 POM_DESCRIPTION=Real-time physically based rendering engine for Android.
 

android/samples/sample-hello-camera/build.gradle

@@ -24,7 +24,7 @@ android {
 
     compileSdkVersion versions.compileSdk
     defaultConfig {
-        applicationId "com.google.android.filament.hellocam"
+        applicationId "com.google.android.filament.hellocamera"
         minSdkVersion 23
         targetSdkVersion versions.targetSdk
     }

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/usertoken">https://central.sonatype.com/usertoken</a>
-and select <strong>Generate User Token</strong>.</p>
+<a href="https://central.sonatype.com/account">https://central.sonatype.com/account</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/building.html

@@ -434,7 +434,7 @@ 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 class="language-c++">for (int i = 0; i &lt; max; i++) {
+<pre><code>for (int i = 0; i &lt; max; i++) {
 }
 
 class Foo {
@@ -227,23 +227,11 @@ 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 class="language-c++">extern int gGlobalWarming;
+<pre><code>extern int gGlobalWarming;
 
 class FooBar {
 public:
-    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
-    }
-
+    void methodName();
     int sizeInBytes;
 private:
     int mAttributeName;
@@ -260,7 +248,7 @@ 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 class="language-c++">/*
+<pre><code>/*
  * Copyright (C) 2018 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
@@ -305,7 +293,7 @@ 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 class="language-c++">/*
+<pre><code>/*
  * Copyright (C) 2018 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
@@ -348,7 +336,7 @@ 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 class="language-c++">auto foo = new Foo();
+<pre><code>auto foo = new Foo();
 for (auto&amp; i : collection) { }
 </code></pre>
 

docs/dup/intro.html

@@ -181,7 +181,7 @@ important for <code>matc</code> (material compiler).</p>
 }
 
 dependencies {
-    implementation 'com.google.android.filament:filament-android:1.66.1'
+    implementation 'com.google.android.filament:filament-android:1.65.0'
 }
 </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; 1.66.1'
+<pre><code class="language-shell">pod 'Filament', '~&gt; 1.65.0'
 </code></pre>
 <h2 id="documentation"><a class="header" href="#documentation">Documentation</a></h2>
 <ul>

docs/dup/renderdiff.html

@@ -1,341 +0,0 @@
-<!DOCTYPE HTML>
-<html lang="en" class="light sidebar-visible" dir="ltr">
-    <head>
-        <!-- Book generated using mdBook -->
-        <meta charset="UTF-8">
-        <title>renderdiff - 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="rendering-difference-test"><a class="header" href="#rendering-difference-test">Rendering Difference Test</a></h1>
-<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 <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 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>
-<ul>
-<li>Set up a virtual environment (from the root directory)
-<pre><code>python3 -m venv venv
-. ./venv/bin/activate
-</code></pre>
-</li>
-<li>Install the rendering dependencies
-<pre><code>pip install -r test/renderdiff/src/rendering_requirements.txt
-</code></pre>
-</li>
-<li>Install the viewer depdencies
-<pre><code>pip install -r test/renderdiff/src/viewer_requirements.txt
-</code></pre>
-</li>
-<li>For the commands in the following section, do not exit the virtual environment. Once you've
-completed all your work, you can exit with
-<pre><code>deactivate
-</code></pre>
-</li>
-</ul>
-<h2 id="running-the-test-locally"><a class="header" href="#running-the-test-locally">Running the test locally</a></h2>
-<ul>
-<li>To run the same presbumit as <a href="presubmit-renderdiff"><code>test-renderdiff</code></a>, you can do
-<pre><code>bash test/renderdiff/local_test.sh
-</code></pre>
-</li>
-<li>This script will generate the renderings based on the current state of your repo.
-Additionally, it will also compare the generated images with corresponding images in the
-golden repo.</li>
-<li>To just render without running the test, you could use the following script
-<pre><code>bash test/renderdiff/generate.sh
-</code></pre>
-</li>
-</ul>
-<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:
-https://github.com/google/filament-assets. Filament team members should have access to write
-to the repository. A typical flow for updating the goldens is to upload your changed images
-into <strong>branch</strong> of <code>filament-assets</code>. This branch is paired with a PR or commit on the
-<code>filament</code> repo.</p>
-<p>As an example, imagine I am working on a PR, and I've uploaded my change, which is in a
-branch called <code>my-pr-branch</code>, to <code>filament</code>. This PR requires updating the golden. We would do
-it in the following fashion</p>
-<h3 id="using-a-script-to-update-the-golden-repo"><a class="header" href="#using-a-script-to-update-the-golden-repo">Using a script to update the golden repo</a></h3>
-<ul>
-<li>Run interactive mode in the <code>update_golden.py</code> script.
-<pre><code>python3 test/renderdiff/src/update_golden.py
-</code></pre>
-</li>
-<li>This will guide you through a series of steps to push the changes to a remote branch on
-<code>filament-assets</code>.</li>
-</ul>
-<h3 id="manually-updating-the-golden-repo"><a class="header" href="#manually-updating-the-golden-repo">Manually updating the golden repo</a></h3>
-<ul>
-<li>Check out the golden repo
-<pre><code>git clone git@github.com:google/filament-assets.git
-</code></pre>
-</li>
-<li>Create a branch on the golden repo
-<pre><code>cd filament-assets
-git switch -c my-pr-branch-golden
-</code></pre>
-</li>
-<li>Copy the new images to their appropriate place in <code>filament-assets</code></li>
-<li>Push the <code>filament-assets</code> working branch to remote
-<pre><code>git push origin my-pr-branch-golden
-</code></pre>
-</li>
-<li>In the commit message of your working branch on <code>filament</code>, add the following line
-<pre><code>RDIFF_BBRANCH=my-pr-branch-golden
-</code></pre>
-</li>
-</ul>
-<p>Doing the above has multiple effects:</p>
-<ul>
-<li>The presubmit test <a href="https://github.com/google/filament/blob/e85dfe75c86106a05019e13ccdbef67e030af675/.github/workflows/presubmit.yml#L118"><code>test-renderdiff</code></a> will test against the provided
-branch of the golden repo (i.e. <code>my-pr-branch-golden</code>).</li>
-<li>If the PR is merged, then there is another workflow that will merge <code>my-pr-branch-golden</code>
-to the <code>main</code> branch of the golden repo.</li>
-</ul>
-<h2 id="viewing-test-results"><a class="header" href="#viewing-test-results">Viewing test results</a></h2>
-<p>We provide a viewer for looking at the result of a test run. The viewer is a webapp that can
-be used by pointing your browser to a localhost port. If you input the viewer with a PR or a
-directory, it will parse the test result and show the results and the rendered and/or golden
-images.</p>
-<p><img src="../images/renderdiff_example.png" alt="Viewer" /></p>
-<p>To run the viewer of a test output directory that has been generated locally, you would run
-the following</p>
-<pre><code>python3 test/renderdiff/src/viewer.py --diff=[test output]
-</code></pre>
-<p>where <code>[test output]</code> is a directory containing the <code>compare_results.json</code> of the test run.
-For example, it could be <code>out/renderdiff/diffs/presubmit</code> for the standard path to the
-<code>presubmit</code> test output.</p>
-<p>To see the results of a Pull Request initiated test run, you would do the following</p>
-<pre><code>python3 test/renderdiff/src/viewer.py --pr_number=[PR #] --github_token=[github token]
-</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>
-
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-                        <!-- Mobile navigation buttons -->
-                            <a rel="prev" href="../notes/tests.html" class="mobile-nav-chapters previous" title="Previous chapter" aria-label="Previous chapter" aria-keyshortcuts="Left">
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-                        <i class="fa fa-angle-right"></i>
-                    </a>
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-            window.playground_copyable = true;
-        </script>
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-        <script src="../mark.min.js"></script>
-        <script src="../searcher.js"></script>
-
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-        <script src="../highlight.js"></script>
-        <script src="../book.js"></script>
-
-        <!-- Custom JS scripts -->
-
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-    </div>
-    </body>
-</html>

docs/notes/framegraph.html

@@ -335,7 +335,7 @@ nodes</li>
                                 <i class="fa fa-angle-left"></i>
                             </a>
 
-                            <a rel="next prefetch" href="../notes/tests.html" class="mobile-nav-chapters next" title="Next chapter" aria-label="Next chapter" aria-keyshortcuts="Right">
+                            <a rel="next prefetch" href="../notes/libs.html" class="mobile-nav-chapters next" title="Next chapter" aria-label="Next chapter" aria-keyshortcuts="Right">
                                 <i class="fa fa-angle-right"></i>
                             </a>
 
@@ -349,7 +349,7 @@ nodes</li>
                         <i class="fa fa-angle-left"></i>
                     </a>
 
-                    <a rel="next prefetch" href="../notes/tests.html" class="nav-chapters next" title="Next chapter" aria-label="Next chapter" aria-keyshortcuts="Right">
+                    <a rel="next prefetch" href="../notes/libs.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/notes/libs.html

@@ -165,7 +165,7 @@
 
                     <nav class="nav-wrapper" aria-label="Page navigation">
                         <!-- Mobile navigation buttons -->
-                            <a rel="prev" href="../dup/renderdiff.html" class="mobile-nav-chapters previous" title="Previous chapter" aria-label="Previous chapter" aria-keyshortcuts="Left">
+                            <a rel="prev" href="../notes/framegraph.html" class="mobile-nav-chapters previous" title="Previous chapter" aria-label="Previous chapter" aria-keyshortcuts="Left">
                                 <i class="fa fa-angle-left"></i>
                             </a>
 
@@ -179,7 +179,7 @@
             </div>
 
             <nav class="nav-wide-wrapper" aria-label="Page navigation">
-                    <a rel="prev" href="../dup/renderdiff.html" class="nav-chapters previous" title="Previous chapter" aria-label="Previous chapter" aria-keyshortcuts="Left">
+                    <a rel="prev" href="../notes/framegraph.html" class="nav-chapters previous" title="Previous chapter" aria-label="Previous chapter" aria-keyshortcuts="Left">
                         <i class="fa fa-angle-left"></i>
                     </a>
 

docs/notes/tests.html

@@ -1,215 +0,0 @@
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-<html lang="en" class="light sidebar-visible" dir="ltr">
-    <head>
-        <!-- Book generated using mdBook -->
-        <meta charset="UTF-8">
-        <title>Tests - Filament</title>
-
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-        <meta name="viewport" content="width=device-width, initial-scale=1">
-        <meta name="theme-color" content="#ffffff">
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-        <link rel="stylesheet" href="../css/variables.css">
-        <link rel="stylesheet" href="../css/general.css">
-        <link rel="stylesheet" href="../css/chrome.css">
-
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-
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-
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-        <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));
-                }
-
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-                    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>
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-            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">
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-                        -->
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-                            <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>
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-
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-                        <ul id="searchresults">
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-                    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="tests"><a class="header" href="#tests">Tests</a></h1>
-<p>Filament has a collection of tests that can be run locally. Many of them are used
-for in our Continuation Integration flow <a href="https://https://github.com/google/filament/tree/main/.github/workflows">on github</a>.</p>
-
-                    </main>
-
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docs/remote/update.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, commit the changed files"
+echo "All done! Next, make a git commit that updates docs/remote."

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 -n1 --pretty=%B {commit_hash}', cwd=ROOT_DIR)
+  res, ret = execute(f'git log --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={commit_hash}')
+        print(f'Found tag={tag} in commit message')
       return True
   return False
 

docs_src/build/duplicates.json

@@ -78,11 +78,5 @@
     },
     "docs_src/README.md": {
         "dest": "dup/docs.md"
-    },
-    "test/renderdiff/README.md": {
-        "dest": "dup/renderdiff.md",
-        "link_transforms": {
-            "docs/images/": "../images/"
-        }
     }
 }

docs_src/build/requirements.txt

@@ -1,15 +0,0 @@
-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

@@ -140,8 +140,6 @@ if __name__ == "__main__":
   res, err = execute('mdbook build', cwd=MDBOOK_DIR)
   assert res == 0, f"failed to execute `mdbook`. return-code={res} err=\"{err}\""
 
-  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.copytree(RAW_COPIES_DIR, BOOK_OUPUT_DIR, 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

@@ -27,8 +27,6 @@
     - [Code coverage analysis](./notes/coverage.md)
     - [Performance analysis](./notes/performance_analysis.md)
   - [Framegraph](./notes/framegraph.md)
-  - [Tests](./notes/tests.md)
-    - [renderdiff](./dup/renderdiff.md)
   - [Libraries](./notes/libs.md)
     - [bluegl](./dup/bluegl.md)
     - [bluevk](./dup/bluevk.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/usertoken](https://central.sonatype.com/usertoken)
-and select **Generate User Token**.
+[https://central.sonatype.com/account](https://central.sonatype.com/account) 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/tests.md

@@ -1,4 +0,0 @@
-# Tests
-
-Filament has a collection of tests that can be run locally. Many of them are used
-for in our Continuation Integration flow [on github](https://https://github.com/google/filament/tree/main/.github/workflows).

docs_src/src_raw/remote/update.sh

@@ -0,0 +1,17 @@
+#!/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."

filament/CMakeLists.txt

@@ -84,8 +84,6 @@ set(SRCS
         src/InstanceBuffer.cpp
         src/LightManager.cpp
         src/Material.cpp
-        src/MaterialCache.cpp
-        src/MaterialDefinition.cpp
         src/MaterialInstance.cpp
         src/MaterialInstanceManager.cpp
         src/MaterialParser.cpp
@@ -117,7 +115,6 @@ 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
@@ -178,8 +175,6 @@ set(PRIVATE_HDRS
         src/HwRenderPrimitiveFactory.h
         src/HwVertexBufferInfoFactory.h
         src/Intersections.h
-        src/MaterialCache.h
-        src/MaterialDefinition.h
         src/MaterialParser.h
         src/MaterialInstanceManager.h
         src/PIDController.h
@@ -197,7 +192,6 @@ 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
@@ -251,10 +245,9 @@ 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/clearDepth.mat
+        src/materials/blitArray.mat
         src/materials/bloom/bloomDownsample.mat
         src/materials/bloom/bloomDownsample2x.mat
         src/materials/bloom/bloomDownsample9.mat
@@ -708,13 +701,6 @@ 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
@@ -736,18 +722,6 @@ 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/backend/CMakeLists.txt

@@ -78,8 +78,6 @@ if (FILAMENT_SUPPORTS_OPENGL AND NOT FILAMENT_USE_EXTERNAL_GLES3)
             src/opengl/GLTexture.h
             src/opengl/GLUtils.cpp
             src/opengl/GLUtils.h
-            src/opengl/GLMemoryMappedBuffer.cpp
-            src/opengl/GLMemoryMappedBuffer.h
             src/opengl/OpenGLBlobCache.cpp
             src/opengl/OpenGLBlobCache.h
             src/opengl/OpenGLContext.cpp
@@ -104,8 +102,6 @@ if (FILAMENT_SUPPORTS_OPENGL AND NOT FILAMENT_USE_EXTERNAL_GLES3)
         list(APPEND SRCS src/VirtualMachineEnv.cpp)
     endif ()
     if (ANDROID)
-        list(APPEND SRCS src/AndroidNativeWindow.cpp)
-        list(APPEND SRCS src/AndroidSwapChainHelper.cpp)
         list(APPEND SRCS src/opengl/platforms/ExternalStreamManagerAndroid.cpp)
         list(APPEND SRCS src/opengl/platforms/PlatformEGLAndroid.cpp)
     elseif (IOS)
@@ -181,7 +177,6 @@ endif()
 if (FILAMENT_SUPPORTS_VULKAN)
     list(APPEND SRCS
             include/backend/platforms/VulkanPlatform.h
-            src/vulkan/VulkanAsyncHandles.cpp
             src/vulkan/VulkanAsyncHandles.h
             src/vulkan/VulkanBlitter.cpp
             src/vulkan/VulkanBlitter.h
@@ -220,10 +215,6 @@ if (FILAMENT_SUPPORTS_VULKAN)
             src/vulkan/VulkanReadPixels.h
             src/vulkan/VulkanSamplerCache.cpp
             src/vulkan/VulkanSamplerCache.h
-            src/vulkan/VulkanSemaphore.cpp
-            src/vulkan/VulkanSemaphore.h
-            src/vulkan/VulkanSemaphoreManager.cpp
-            src/vulkan/VulkanSemaphoreManager.h
             src/vulkan/VulkanStagePool.cpp
             src/vulkan/VulkanStagePool.h
             src/vulkan/VulkanSwapChain.cpp
@@ -296,8 +287,6 @@ 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
@@ -471,13 +460,6 @@ 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
@@ -504,13 +486,6 @@ 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
@@ -591,8 +566,6 @@ if (APPLE OR LINUX)
         test/test_ReadPixels.cpp
         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

@@ -197,7 +197,6 @@ constexpr std::string_view to_string(Backend const backend) noexcept {
  * - The Metal backend can prefer precompiled Metal libraries, while falling back to MSL.
  */
 enum class ShaderLanguage {
-    UNSPECIFIED = -1,
     ESSL1 = 0,
     ESSL3 = 1,
     SPIRV = 2,
@@ -220,8 +219,6 @@ constexpr const char* shaderLanguageToString(ShaderLanguage shaderLanguage) noex
             return "Metal precompiled library";
         case ShaderLanguage::WGSL:
             return "WGSL";
-        case ShaderLanguage::UNSPECIFIED:
-            return "Unspecified";
     }
     return "UNKNOWN";
 }
@@ -559,21 +556,12 @@ constexpr TargetBufferFlags getTargetBufferFlagsAt(size_t index) noexcept {
 }
 
 /**
- * How the buffer will be used.
+ * Frequency at which a buffer is expected to be modified and used. This is used as an hint
+ * for the driver to make better decisions about managing memory internally.
  */
 enum class BufferUsage : uint8_t {
-    STATIC              = 0,    //!< (legacy) content modified once, used many times
-    DYNAMIC             = 1,    //!< (legacy) content modified frequently, used many times
-    DYNAMIC_BIT         = 0x1,  //!< buffer can be modified frequently, used many times
-    SHARED_WRITE_BIT    = 0x04, //!< buffer can be memory mapped for write operations
-};
-
-/**
- * How the buffer will be mapped.
- */
-enum class MapBufferAccessFlags : uint8_t {
-    WRITE_BIT               = 0x2,  //!< buffer is mapped from writing
-    INVALIDATE_RANGE_BIT    = 0x4,  //!< the mapped range content is lost
+    STATIC,      //!< content modified once, used many times
+    DYNAMIC,     //!< content modified frequently, used many times
 };
 
 /**
@@ -639,15 +627,6 @@ enum class ShaderModel : uint8_t {
 };
 static constexpr size_t SHADER_MODEL_COUNT = 2;
 
-constexpr std::string_view to_string(ShaderModel model) noexcept {
-    switch (model) {
-        case ShaderModel::MOBILE:
-            return "mobile";
-        case ShaderModel::DESKTOP:
-            return "desktop";
-    }
-}
-
 /**
  * Primitive types
  */
@@ -713,12 +692,6 @@ enum class Precision : uint8_t {
     DEFAULT
 };
 
-union ConstantValue {
-    int32_t i;
-    float f;
-    bool b;
-};
-
 /**
  * Shader compiler priority queue
  *
@@ -1703,8 +1676,6 @@ 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;
@@ -1721,11 +1692,6 @@ template<> struct utils::EnableBitMaskOperators<filament::backend::TextureUsage>
         : public std::true_type {};
 template<> struct utils::EnableBitMaskOperators<filament::backend::StencilFace>
         : public std::true_type {};
-template<> struct utils::EnableBitMaskOperators<filament::backend::BufferUsage>
-        : public std::true_type {};
-template<> struct utils::EnableBitMaskOperators<filament::backend::MapBufferAccessFlags>
-        : public std::true_type {};
-
 template<> struct utils::EnableIntegerOperators<filament::backend::TextureCubemapFace>
         : public std::true_type {};
 template<> struct utils::EnableIntegerOperators<filament::backend::FeatureLevel>

filament/backend/include/backend/Handle.h

@@ -45,7 +45,6 @@ struct HwVertexBufferInfo;
 struct HwVertexBuffer;
 struct HwDescriptorSetLayout;
 struct HwDescriptorSet;
-struct HwMemoryMappedBuffer;
 
 /*
  * A handle to a backend resource. HandleBase is for internal use only.
@@ -160,7 +159,6 @@ using VertexBufferHandle        = Handle<HwVertexBuffer>;
 using VertexBufferInfoHandle    = Handle<HwVertexBufferInfo>;
 using DescriptorSetLayoutHandle = Handle<HwDescriptorSetLayout>;
 using DescriptorSetHandle       = Handle<HwDescriptorSet>;
-using MemoryMappedBufferHandle  = Handle<HwMemoryMappedBuffer>;
 
 } // namespace filament::backend
 

filament/backend/include/backend/Platform.h

@@ -91,46 +91,6 @@ 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;
-        /**
-         * 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;
-    };
-
-    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
-        time_point_ns requestedPresentTime;
-        time_point_ns acquireTime;
-        time_point_ns latchTime;
-        time_point_ns firstRefreshStartTime;
-        time_point_ns lastRefreshStartTime;
-        time_point_ns gpuCompositionDoneTime;
-        time_point_ns displayPresentTime;
-        time_point_ns dequeueReadyTime;
-        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.)
@@ -276,7 +236,7 @@ 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) = 0;
+            const DriverConfig& driverConfig) noexcept = 0;
 
     /**
      * Processes the platform's event queue when called from its primary event-handling thread.
@@ -287,65 +247,6 @@ 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
@@ -438,9 +339,6 @@ 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

@@ -50,7 +50,11 @@ public:
         descriptor_binding_t binding;
     };
 
-    using SpecializationConstant = std::variant<int32_t, float, bool>;
+    struct SpecializationConstant {
+        using Type = std::variant<int32_t, float, bool>;
+        uint32_t id;    // id set in glsl
+        Type value;     // value and type
+    };
 
     struct Uniform { // For ES2 support
         utils::CString name;    // full qualified name of the uniform field
@@ -114,7 +118,7 @@ public:
     Program& multiview(bool multiview) noexcept;
 
     // For ES2 support only...
-    Program& uniforms(uint32_t index, utils::CString name, UniformInfo uniforms);
+    Program& uniforms(uint32_t index, utils::CString name, UniformInfo uniforms) noexcept;
     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) = 0;
+            void* UTILS_NULLABLE nativeWindow, uint64_t flags) noexcept = 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) = 0;
+            uint32_t width, uint32_t height, uint64_t flags) noexcept = 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 as the main context and makes it
+     * Creates an OpenGL context with the same configuration than 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 must be called from the same thread where createContext() was called.
+     * this thread.
      */
     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) override;
+            const DriverConfig& driverConfig) noexcept 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) override;
+            const DriverConfig& driverConfig) noexcept override;
 
     int getOSVersion() const noexcept final { return 0; }
 

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

@@ -25,7 +25,6 @@
 #include <EGL/eglext.h>
 #include <EGL/eglplatform.h>
 
-#include <utils/compiler.h>
 #include <utils/Invocable.h>
 
 #include <initializer_list>
@@ -81,7 +80,7 @@ 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) override;
+    Driver* createDriver(void* sharedContext, const DriverConfig& driverConfig) noexcept override;
 
     /**
      * This returns zero. This method can be overridden to return something more useful.
@@ -101,6 +100,10 @@ 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;
@@ -155,9 +158,16 @@ protected:
         return egl.makeCurrent(context, mEGLDummySurface, mEGLDummySurface);
     }
 
-    EGLDisplay getEglDisplay() const noexcept { return mEGLDisplay; }
-    EGLConfig getEglConfig() const noexcept { return mEGLConfig; }
-    EGLConfig getSuitableConfigForSwapChain(uint64_t flags, bool window, bool pbuffer) const;
+    // 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;
 
     // supported extensions detected at runtime
     struct {
@@ -174,11 +184,7 @@ protected:
         } egl;
     } ext;
 
-    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);
-
+    struct SwapChainEGL : public Platform::SwapChain {
         EGLSurface sur = EGL_NO_SURFACE;
         Config attribs{};
         EGLNativeWindowType nativeWindow{};
@@ -194,25 +200,10 @@ protected:
         ~ExternalImageEGL() override;
     };
 
-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;
-
+protected:
     EGLConfig findSwapChainConfig(uint64_t flags, bool window, bool pbuffer) const;
 
-    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;
-
+private:
     class EGL {
         EGLDisplay& mEGLDisplay;
         EGLSurface mCurrentDrawSurface = EGL_NO_SURFACE;
@@ -227,8 +218,6 @@ private:
             return makeCurrent(mCurrentContext, drawSurface, readSurface);
         }
     } egl{ mEGLDisplay };
-
-    bool checkIfMSAASwapChainSupported(uint32_t samples) const noexcept;
 };
 
 } // namespace filament::backend

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

@@ -17,10 +17,7 @@
 #ifndef TNT_FILAMENT_BACKEND_OPENGL_OPENGL_PLATFORM_EGL_ANDROID_H
 #define TNT_FILAMENT_BACKEND_OPENGL_OPENGL_PLATFORM_EGL_ANDROID_H
 
-#include "AndroidSwapChainHelper.h"
-
 #include <backend/AcquiredImage.h>
-#include <backend/DriverEnums.h>
 #include <backend/Platform.h>
 #include <backend/platforms/OpenGLPlatform.h>
 #include <backend/platforms/PlatformEGL.h>
@@ -28,8 +25,6 @@
 #include <utils/android/PerformanceHintManager.h>
 #include <utils/compiler.h>
 
-#include <math/mat3.h>
-
 #include <chrono>
 
 #include <stddef.h>
@@ -72,17 +67,9 @@ public:
      * @return `true` on success, `false` on failure. The default implementation
      *         returns `false`.
      */
-    bool convertSyncToFd(Sync* sync, int* fd) noexcept;
+    bool convertSyncToFd(Platform::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
 
@@ -93,22 +80,12 @@ protected:
     int getOSVersion() const noexcept override;
 
     Driver* createDriver(void* sharedContext,
-            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;
+            const Platform::DriverConfig& driverConfig) noexcept override;
 
     // --------------------------------------------------------------------------------------------
     // OpenGLPlatform Interface
 
-    struct SyncEGLAndroid : public Sync {
+    struct SyncEGLAndroid : public Platform::Sync {
         EGLSyncKHR sync;
     };
 
@@ -129,8 +106,8 @@ protected:
 
     Stream* createStream(void* nativeStream) noexcept override;
     void destroyStream(Stream* stream) noexcept override;
-    Sync* createSync() noexcept override;
-    void destroySync(Sync* sync) noexcept override;
+    Platform::Sync* createSync() noexcept override;
+    void destroySync(Platform::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;
@@ -143,7 +120,7 @@ protected:
      */
     AcquiredImage transformAcquiredImage(AcquiredImage source) noexcept override;
 
-    ExternalTexture* createExternalImageTexture() noexcept override;
+    OpenGLPlatform::ExternalTexture* createExternalImageTexture() noexcept override;
     void destroyExternalImageTexture(ExternalTexture* texture) noexcept override;
 
     struct ExternalImageEGLAndroid : public ExternalImageEGL {
@@ -163,28 +140,12 @@ 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;
-
     struct InitializeJvmForPerformanceManagerIfNeeded {
         InitializeJvmForPerformanceManagerIfNeeded();
     };
@@ -198,15 +159,13 @@ private:
     InitializeJvmForPerformanceManagerIfNeeded const mInitializeJvmForPerformanceManagerIfNeeded;
     utils::PerformanceHintManager mPerformanceHintManager;
     utils::PerformanceHintManager::Session mPerformanceHintSession;
-    SwapChainEGLAndroid* mCurrentDrawSwapChain{};
 
     using clock = std::chrono::high_resolution_clock;
     clock::time_point mStartTimeOfActualWork;
 
-    int32_t (*ANativeWindow_setProducerThrottlingEnabled)(ANativeWindow* window, bool enabled) = nullptr;
-    int32_t (*ANativeWindow_isProducerThrottlingEnabled)(ANativeWindow* window, bool* outEnabled) = nullptr;
+    void* mNativeWindowLib = nullptr;
+    int32_t (*ANativeWindow_getBuffersDefaultDataSpace)(ANativeWindow* window) = nullptr;
     bool mAssertNativeWindowIsValid = false;
-    bool mHasProducerThrottlingControl = false;
 };
 
 } // 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) override;
+            const Platform::DriverConfig& driverConfig) noexcept override;
 
 protected:
     bool isOpenGL() const noexcept override;

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

@@ -26,10 +26,7 @@
 
 #include <backend/DriverEnums.h>
 
-#include <shared_mutex>
-#include <thread>
 #include <vector>
-#include <unordered_map>
 
 namespace filament::backend {
 
@@ -42,7 +39,7 @@ protected:
     // Platform Interface
 
     Driver* createDriver(void* sharedGLContext,
-            const DriverConfig& driverConfig) override;
+            const DriverConfig& driverConfig) noexcept override;
 
     int getOSVersion() const noexcept final override { return 0; }
 
@@ -51,10 +48,6 @@ 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;
@@ -62,15 +55,11 @@ 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) override;
+    Driver* createDriver(void* sharedContext, const Platform::DriverConfig& driverConfig) noexcept 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) override;
+    Driver* createDriver(void* sharedGLContext, const DriverConfig& driverConfig) noexcept 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) override;
+            const Platform::DriverConfig& driverConfig) noexcept override;
 
     int getOSVersion() const noexcept final override { return 0; }
 
@@ -61,12 +61,8 @@ protected:
     HWND mHWnd = NULL;
     HDC mWhdc = NULL;
     PIXELFORMATDESCRIPTOR mPfd = {};
-    std::vector<int> mAttribs;
-
-    // For shared contexts
-    static constexpr int SHARED_CONTEXT_NUM = 1;
     std::vector<HGLRC> mAdditionalContexts;
-    std::atomic<int> mNextFreeSharedContextIndex{0};
+    std::vector<int> mAttribs;
 };
 
 } // 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) override;
+            const Platform::DriverConfig& driverConfig) noexcept 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) override;
+            Platform::DriverConfig const& driverConfig) noexcept override;
 
     int getOSVersion() const noexcept override {
         return 0;

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

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

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

@@ -61,7 +61,7 @@ class CommandBase {
 protected:
     using Execute = Dispatcher::Execute;
 
-    constexpr explicit CommandBase(Execute const execute) noexcept : mExecute(execute) {}
+    constexpr explicit CommandBase(Execute execute) noexcept : mExecute(execute) {}
 
 public:
     // alignment of all Commands in the CommandStream
@@ -70,7 +70,7 @@ public:
     }
 
     // executes this command and returns the next one
-    CommandBase* execute(Driver& driver) {
+    inline CommandBase* execute(Driver& driver) {
         // returning the next command by output parameter allows the compiler to perform the
         // tail-call optimization in the function called by mExecute, however that comes at
         // a cost here (writing and reading the stack at each iteration), in the end it's
@@ -80,7 +80,7 @@ public:
         return reinterpret_cast<CommandBase*>(reinterpret_cast<intptr_t>(this) + next);
     }
 
-    ~CommandBase() noexcept = default;
+    inline ~CommandBase() noexcept = default;
 
 private:
     Execute mExecute;
@@ -135,7 +135,7 @@ struct CommandType<void (Driver::*)(ARGS...)> {
 
     public:
         template<typename M, typename D>
-        static void execute(M&& method, D&& driver, CommandBase* base, intptr_t* next) {
+        static inline void execute(M&& method, D&& driver, CommandBase* base, intptr_t* next) {
             Command* self = static_cast<Command*>(base);
             *next = align(sizeof(Command));
 #if DEBUG_COMMAND_STREAM
@@ -147,15 +147,15 @@ struct CommandType<void (Driver::*)(ARGS...)> {
         }
 
         // A command can be moved
-        Command(Command&& rhs) noexcept = default;
+        inline Command(Command&& rhs) noexcept = default;
 
         template<typename... A>
-        explicit constexpr Command(Execute const execute, A&& ... args) noexcept
+        inline explicit constexpr Command(Execute execute, A&& ... args)
                 : CommandBase(execute), mArgs(std::forward<A>(args)...) {
         }
 
         // placement new declared as "throw" to avoid the compiler's null-check
-        void* operator new(std::size_t, void* ptr) noexcept {
+        inline void* operator new(std::size_t, void* ptr) {
             assert_invariant(ptr);
             return ptr;
         }
@@ -171,9 +171,8 @@ class CustomCommand : public CommandBase {
     std::function<void()> mCommand;
     static void execute(Driver&, CommandBase* base, intptr_t* next);
 public:
-    CustomCommand(CustomCommand&& rhs) = default;
-
-    explicit CustomCommand(std::function<void()> cmd)
+    inline CustomCommand(CustomCommand&& rhs) = default;
+    inline explicit CustomCommand(std::function<void()> cmd)
             : CommandBase(execute), mCommand(std::move(cmd)) { }
 };
 
@@ -185,7 +184,7 @@ class NoopCommand : public CommandBase {
         *next = static_cast<NoopCommand*>(self)->mNext;
     }
 public:
-    constexpr explicit NoopCommand(void* next) noexcept
+    inline constexpr explicit NoopCommand(void* next) noexcept
             : CommandBase(execute), mNext(intptr_t((char *)next - (char *)this)) { }
 };
 
@@ -208,8 +207,8 @@ class CommandStream {
     template<typename T>
     struct AutoExecute {
         T closure;
-        explicit AutoExecute(T&& closure) : closure(std::forward<T>(closure)) {}
-        ~AutoExecute() { closure(); }
+        inline explicit AutoExecute(T&& closure) : closure(std::forward<T>(closure)) {}
+        inline ~AutoExecute() { closure(); }
     };
 
 public:
@@ -222,7 +221,7 @@ public:
 
 public:
 #define DECL_DRIVER_API(methodName, paramsDecl, params)                                         \
-    inline void methodName(paramsDecl) noexcept {                                               \
+    inline void methodName(paramsDecl) {                                                        \
         DEBUG_COMMAND_BEGIN(methodName, false, params);                                         \
         using Cmd = COMMAND_TYPE(methodName);                                                   \
         void* const p = allocateCommand(CommandBase::align(sizeof(Cmd)));                       \
@@ -231,7 +230,7 @@ public:
     }
 
 #define DECL_DRIVER_API_SYNCHRONOUS(RetType, methodName, paramsDecl, params)                    \
-    inline RetType methodName(paramsDecl) noexcept {                                            \
+    inline RetType methodName(paramsDecl) {                                                     \
         DEBUG_COMMAND_BEGIN(methodName, true, params);                                          \
         AutoExecute callOnExit([=, this](){                                                     \
             DEBUG_COMMAND_END(methodName, true);                                                \
@@ -240,7 +239,7 @@ public:
     }
 
 #define DECL_DRIVER_API_RETURN(RetType, methodName, paramsDecl, params)                         \
-    inline RetType methodName(paramsDecl) noexcept {                                            \
+    inline RetType methodName(paramsDecl) {                                                     \
         DEBUG_COMMAND_BEGIN(methodName, false, params);                                         \
         RetType result = mDriver.methodName##S();                                               \
         using Cmd = COMMAND_TYPE(methodName##R);                                                \
@@ -256,7 +255,7 @@ public:
     // This is for debugging only. Currently, CircularBuffer can only be written from a
     // single thread. In debug builds we assert this condition.
     // Call this first in the render loop.
-    void debugThreading() noexcept {
+    inline void debugThreading() noexcept {
 #ifndef NDEBUG
         mThreadId = utils::ThreadUtils::getThreadId();
 #endif
@@ -282,11 +281,11 @@ public:
      */
     template<typename PodType,
             typename = typename std::enable_if<std::is_trivially_destructible<PodType>::value>::type>
-    PodType* allocatePod(
+    inline PodType* allocatePod(
             size_t count = 1, size_t alignment = alignof(PodType)) noexcept;
 
 private:
-    void* allocateCommand(size_t const size) noexcept {
+    inline void* allocateCommand(size_t size) {
         assert_invariant(utils::ThreadUtils::isThisThread(mThreadId));
         return mCurrentBuffer.allocate(size);
     }

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

@@ -27,8 +27,6 @@
 #include <backend/AcquiredImage.h>
 
 #include <utils/CString.h>
-#include <utils/ImmutableCString.h>
-#include <utils/FixedCapacityVector.h>
 #include <utils/compiler.h>
 
 #include <functional>
@@ -73,11 +71,7 @@ public:
 
     virtual ShaderModel getShaderModel() const noexcept = 0;
 
-    // The shader languages used for shaders for this driver in order of preference, used to inform
-    // matdbg.
-    //
-    // The `preferredLanguage` is only a hint. If the backend supports it, it will appear first in
-    // the list.
+    // The shader language used for shaders for this driver, used to inform matdbg.
     //
     // For OpenGL, this distinguishes whether the driver's shaders are powered by ESSL1 or ESSL3.
     // This information is used by matdbg to display the correct shader code to the web UI and patch
@@ -85,8 +79,7 @@ public:
     //
     // Metal shaders can either be MSL or Metal libraries, but at time of writing, matdbg can only
     // interface with MSL.
-    virtual utils::FixedCapacityVector<ShaderLanguage> getShaderLanguages(
-            ShaderLanguage preferredLanguage) const noexcept = 0;
+    virtual ShaderLanguage getShaderLanguage() const noexcept = 0;
 
     // Returns the dispatcher. This is only called once during initialization of the CommandStream,
     // so it doesn't matter that it's virtual.

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

@@ -108,16 +108,12 @@
     DECL_DRIVER_API_RETURN(R, N, PAIR_ARGS_N(ARG, ##__VA_ARGS__), PAIR_ARGS_N(PARAM, ##__VA_ARGS__))
 
 #define DECL_DRIVER_API_TAGGED_R_N(R, N, ...) \
-    DECL_DRIVER_API_RETURN(R, N, PAIR_ARGS_N(ARG, ##__VA_ARGS__, utils::ImmutableCString&&, tag = {}), \
-            PAIR_ARGS_N(PARAM, ##__VA_ARGS__, utils::ImmutableCString&&, tag))
+    DECL_DRIVER_API_RETURN(R, N, PAIR_ARGS_N(ARG, ##__VA_ARGS__, utils::CString, tag = {}), \
+            PAIR_ARGS_N(PARAM, ##__VA_ARGS__, utils::CString, tag))
 
 #define DECL_DRIVER_API_SYNCHRONOUS_N(R, N, ...) \
     DECL_DRIVER_API_SYNCHRONOUS(R, N, PAIR_ARGS_N(ARG, ##__VA_ARGS__), PAIR_ARGS_N(PARAM, ##__VA_ARGS__))
 
-#define DECL_DRIVER_API_SYNCHRONOUS_TAGGED_N(R, N, ...) \
-    DECL_DRIVER_API_SYNCHRONOUS(R, N, PAIR_ARGS_N(ARG, ##__VA_ARGS__, utils::ImmutableCString, tag = {}), \
-            PAIR_ARGS_N(PARAM, ##__VA_ARGS__, utils::ImmutableCString, tag))
-
 // on some compilers the ##__VA_ARGS__ hack is not supported, so we can't handle 0-parameter APIs
 // with DECL_DRIVER_API_SYNCHRONOUS_N
 #define DECL_DRIVER_API_SYNCHRONOUS_0(R, N) \
@@ -295,11 +291,27 @@ DECL_DRIVER_API_TAGGED_R_N(backend::DescriptorSetLayoutHandle, createDescriptorS
 DECL_DRIVER_API_TAGGED_R_N(backend::DescriptorSetHandle, createDescriptorSet,
         backend::DescriptorSetLayoutHandle, dslh)
 
-DECL_DRIVER_API_TAGGED_R_N(backend::MemoryMappedBufferHandle, mapBuffer,
+DECL_DRIVER_API_N(updateDescriptorSetBuffer,
+        backend::DescriptorSetHandle, dsh,
+        backend::descriptor_binding_t, binding,
         backend::BufferObjectHandle, boh,
-        size_t, offset,
-        size_t, size,
-        backend::MapBufferAccessFlags, access)
+        uint32_t, offset,
+        uint32_t, size
+)
+
+DECL_DRIVER_API_N(updateDescriptorSetTexture,
+        backend::DescriptorSetHandle, dsh,
+        backend::descriptor_binding_t, binding,
+        backend::TextureHandle, th,
+        SamplerParams, params
+)
+
+DECL_DRIVER_API_N(bindDescriptorSet,
+        backend::DescriptorSetHandle, dsh,
+        backend::descriptor_set_t, set,
+        backend::DescriptorSetOffsetArray&&, offsets
+)
+
 
 /*
  * Destroying driver objects
@@ -309,7 +321,7 @@ DECL_DRIVER_API_TAGGED_R_N(backend::MemoryMappedBufferHandle, mapBuffer,
 DECL_DRIVER_API_N(destroyVertexBuffer,          backend::VertexBufferHandle, vbh)
 DECL_DRIVER_API_N(destroyVertexBufferInfo,      backend::VertexBufferInfoHandle, vbih)
 DECL_DRIVER_API_N(destroyIndexBuffer,           backend::IndexBufferHandle, ibh)
-DECL_DRIVER_API_N(destroyBufferObject,          backend::BufferObjectHandle, boh)
+DECL_DRIVER_API_N(destroyBufferObject,          backend::BufferObjectHandle, ibh)
 DECL_DRIVER_API_N(destroyRenderPrimitive,       backend::RenderPrimitiveHandle, rph)
 DECL_DRIVER_API_N(destroyProgram,               backend::ProgramHandle, ph)
 DECL_DRIVER_API_N(destroyTexture,               backend::TextureHandle, th)
@@ -321,7 +333,6 @@ DECL_DRIVER_API_N(destroyFence,                 backend::FenceHandle, fh)
 DECL_DRIVER_API_N(destroySync,                  backend::SyncHandle, sh)
 DECL_DRIVER_API_N(destroyDescriptorSetLayout,   backend::DescriptorSetLayoutHandle, dslh)
 DECL_DRIVER_API_N(destroyDescriptorSet,         backend::DescriptorSetHandle, dsh)
-DECL_DRIVER_API_N(unmapBuffer,                  backend::MemoryMappedBufferHandle, mmbh)
 
 /*
  * Synchronous APIs
@@ -329,14 +340,13 @@ DECL_DRIVER_API_N(unmapBuffer,                  backend::MemoryMappedBufferHandl
  */
 
 DECL_DRIVER_API_SYNCHRONOUS_0(void, terminate)
-DECL_DRIVER_API_SYNCHRONOUS_TAGGED_N(backend::StreamHandle, createStreamNative, void*, stream)
-DECL_DRIVER_API_SYNCHRONOUS_TAGGED_N(backend::StreamHandle, createStreamAcquired)
+DECL_DRIVER_API_SYNCHRONOUS_N(backend::StreamHandle, createStreamNative, void*, stream, utils::CString, tag)
+DECL_DRIVER_API_SYNCHRONOUS_N(backend::StreamHandle, createStreamAcquired, utils::CString, tag)
 DECL_DRIVER_API_SYNCHRONOUS_N(void, setAcquiredImage, backend::StreamHandle, stream, void*, image, const math::mat3f&, transform, backend::CallbackHandler*, handler, backend::StreamCallback, cb, void*, userData)
 DECL_DRIVER_API_SYNCHRONOUS_N(void, setStreamDimensions, backend::StreamHandle, stream, uint32_t, width, uint32_t, height)
 DECL_DRIVER_API_SYNCHRONOUS_N(int64_t, getStreamTimestamp, backend::StreamHandle, stream)
 DECL_DRIVER_API_SYNCHRONOUS_N(void, updateStreams, backend::DriverApi*, driver)
 DECL_DRIVER_API_SYNCHRONOUS_N(backend::FenceStatus, getFenceStatus, backend::FenceHandle, fh)
-DECL_DRIVER_API_SYNCHRONOUS_N(backend::FenceStatus, fenceWait, backend::FenceHandle, fh, uint64_t, timeout)
 DECL_DRIVER_API_SYNCHRONOUS_N(void, getPlatformSync, backend::SyncHandle, sh,
         backend::CallbackHandler*, handler, backend::Platform::SyncCallback, cb, void*, userData)
 DECL_DRIVER_API_SYNCHRONOUS_N(bool, isTextureFormatSupported, backend::TextureFormat, format)
@@ -363,10 +373,9 @@ DECL_DRIVER_API_SYNCHRONOUS_0(size_t, getMaxArrayTextureLayers)
 DECL_DRIVER_API_SYNCHRONOUS_0(math::float2, getClipSpaceParams)
 DECL_DRIVER_API_SYNCHRONOUS_N(void, setupExternalImage2, backend::Platform::ExternalImageHandleRef, image)
 DECL_DRIVER_API_SYNCHRONOUS_N(void, setupExternalImage, void*, image)
-DECL_DRIVER_API_SYNCHRONOUS_N(backend::TimerQueryResult, getTimerQueryValue, backend::TimerQueryHandle, tqh, uint64_t*, elapsedTime)
+DECL_DRIVER_API_SYNCHRONOUS_N(backend::TimerQueryResult, getTimerQueryValue, backend::TimerQueryHandle, query, uint64_t*, elapsedTime)
 DECL_DRIVER_API_SYNCHRONOUS_N(bool, isWorkaroundNeeded, backend::Workaround, workaround)
 DECL_DRIVER_API_SYNCHRONOUS_0(backend::FeatureLevel, getFeatureLevel)
-DECL_DRIVER_API_SYNCHRONOUS_0(size_t, getUniformBufferOffsetAlignment)
 
 /*
  * Updating driver objects
@@ -389,16 +398,16 @@ DECL_DRIVER_API_N(updateBufferObject,
         uint32_t, byteOffset)
 
 DECL_DRIVER_API_N(registerBufferObjectStreams,
-        backend::BufferObjectHandle, boh,
+        backend::BufferObjectHandle, ibh,
         backend::BufferObjectStreamDescriptor&&, streams)
 
 DECL_DRIVER_API_N(updateBufferObjectUnsynchronized,
-        backend::BufferObjectHandle, boh,
+        backend::BufferObjectHandle, ibh,
         backend::BufferDescriptor&&, data,
         uint32_t, byteOffset)
 
 DECL_DRIVER_API_N(resetBufferObject,
-        backend::BufferObjectHandle, boh)
+        backend::BufferObjectHandle, ibh)
 
 DECL_DRIVER_API_N(update3DImage,
         backend::TextureHandle, th,
@@ -418,48 +427,6 @@ DECL_DRIVER_API_N(setExternalStream,
         backend::TextureHandle, th,
         backend::StreamHandle, sh)
 
-DECL_DRIVER_API_N(beginTimerQuery,
-        backend::TimerQueryHandle, tqh)
-
-DECL_DRIVER_API_N(endTimerQuery,
-        backend::TimerQueryHandle, tqh)
-
-DECL_DRIVER_API_N(compilePrograms,
-        backend::CompilerPriorityQueue, priority,
-        backend::CallbackHandler*, handler,
-        backend::CallbackHandler::Callback, callback,
-        void*, user)
-
-DECL_DRIVER_API_N(updateDescriptorSetBuffer,
-        backend::DescriptorSetHandle, dsh,
-        backend::descriptor_binding_t, binding,
-        backend::BufferObjectHandle, boh,
-        uint32_t, offset,
-        uint32_t, size
-)
-
-DECL_DRIVER_API_N(updateDescriptorSetTexture,
-        backend::DescriptorSetHandle, dsh,
-        backend::descriptor_binding_t, binding,
-        backend::TextureHandle, th,
-        SamplerParams, params
-)
-
-DECL_DRIVER_API_N(copyToMemoryMappedBuffer,
-        backend::MemoryMappedBufferHandle, mmbh,
-        size_t, offset,
-        backend::BufferDescriptor&&, data)
-
-DECL_DRIVER_API_N(setPushConstant,
-        backend::ShaderStage, stage,
-        uint8_t, index,
-        backend::PushConstantVariant, value)
-
-/*
- * Setting rendering state
- * -----------------------
- */
-
 DECL_DRIVER_API_N(beginRenderPass,
         backend::RenderTargetHandle, rth,
         const backend::RenderPassParams&, params)
@@ -468,17 +435,17 @@ DECL_DRIVER_API_0(endRenderPass)
 
 DECL_DRIVER_API_0(nextSubpass)
 
-DECL_DRIVER_API_N(bindPipeline,
-        backend::PipelineState const&, state)
+DECL_DRIVER_API_N(beginTimerQuery,
+        backend::TimerQueryHandle, query)
 
-DECL_DRIVER_API_N(bindRenderPrimitive,
-        backend::RenderPrimitiveHandle, rph)
+DECL_DRIVER_API_N(endTimerQuery,
+        backend::TimerQueryHandle, query)
 
-DECL_DRIVER_API_N(bindDescriptorSet,
-        backend::DescriptorSetHandle, dsh,
-        backend::descriptor_set_t, set,
-        backend::DescriptorSetOffsetArray&&, offsets
-)
+DECL_DRIVER_API_N(compilePrograms,
+        backend::CompilerPriorityQueue, priority,
+        backend::CallbackHandler*, handler,
+        backend::CallbackHandler::Callback, callback,
+        void*, user)
 
 /*
  * Swap chain
@@ -497,6 +464,11 @@ DECL_DRIVER_API_N(commit,
  * -----------------------
  */
 
+DECL_DRIVER_API_N(setPushConstant,
+        backend::ShaderStage, stage,
+        uint8_t, index,
+        backend::PushConstantVariant, value)
+
 DECL_DRIVER_API_N(insertEventMarker,
         const char*, string)
 
@@ -557,6 +529,12 @@ DECL_DRIVER_API_N(blit,
         math::uint2, srcOrigin,
         math::uint2, size)
 
+DECL_DRIVER_API_N(bindPipeline,
+        backend::PipelineState const&, state)
+
+DECL_DRIVER_API_N(bindRenderPrimitive,
+        backend::RenderPrimitiveHandle, rph)
+
 DECL_DRIVER_API_N(draw2,
         uint32_t, indexOffset,
         uint32_t, indexCount,

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

@@ -21,7 +21,6 @@
 
 #include <utils/Allocator.h>
 #include <utils/CString.h>
-#include <utils/ImmutableCString.h>
 #include <utils/Log.h>
 #include <utils/Panic.h>
 #include <utils/compiler.h>
@@ -53,16 +52,16 @@ namespace filament::backend {
 class DebugTag {
 public:
     DebugTag();
-    void writePoolHandleTag(HandleBase::HandleId key, utils::ImmutableCString&& tag) noexcept;
-    void writeHeapHandleTag(HandleBase::HandleId key, utils::ImmutableCString&& tag) noexcept;
-    utils::ImmutableCString findHandleTag(HandleBase::HandleId key) const noexcept;
+    void writePoolHandleTag(HandleBase::HandleId key, utils::CString&& tag) noexcept;
+    void writeHeapHandleTag(HandleBase::HandleId key, utils::CString&& tag) noexcept;
+    utils::CString findHandleTag(HandleBase::HandleId key) const noexcept;
 
 private:
     // This is used to associate a tag to a handle. mDebugTags is only written the in the main
     // driver thread, but it can be accessed from any thread, because it's called from handle_cast<>
     // which is used by synchronous calls.
     mutable utils::Mutex mDebugTagLock;
-    tsl::robin_map<HandleBase::HandleId, utils::ImmutableCString> mDebugTags;
+    tsl::robin_map<HandleBase::HandleId, utils::CString> mDebugTags;
 };
 
 /*
@@ -71,12 +70,12 @@ private:
 template<size_t P0, size_t P1, size_t P2>
 class HandleAllocator : public DebugTag {
 public:
-    HandleAllocator(const char* name, size_t size);
+    HandleAllocator(const char* name, size_t size) noexcept;
     HandleAllocator(const char* name, size_t size,
-            bool disableUseAfterFreeCheck, bool disableHeapHandleTags);
+            bool disableUseAfterFreeCheck, bool disableHeapHandleTags) noexcept;
     HandleAllocator(HandleAllocator const& rhs) = delete;
     HandleAllocator& operator=(HandleAllocator const& rhs) = delete;
-    ~HandleAllocator() noexcept;
+    ~HandleAllocator();
 
     /*
      * Constructs a D object and returns a Handle<D>
@@ -107,7 +106,7 @@ public:
      *
      */
     template<typename D>
-    Handle<D> allocate() {
+    Handle<D> allocate() noexcept {
         Handle<D> h{ allocateHandle<D>() };
         return h;
     }
@@ -223,7 +222,7 @@ public:
         return static_cast<Dp>(p);
     }
 
-    utils::ImmutableCString getHandleTag(HandleBase::HandleId key) const noexcept;
+    utils::CString getHandleTag(HandleBase::HandleId key) const noexcept;
 
     template<typename B>
     bool is_valid(Handle<B>& handle) {
@@ -249,7 +248,7 @@ public:
         return handle_cast<Dp>(const_cast<Handle<B>&>(handle));
     }
 
-    void associateTagToHandle(HandleBase::HandleId id, utils::ImmutableCString&& tag) noexcept {
+    void associateTagToHandle(HandleBase::HandleId id, utils::CString&& tag) noexcept {
         if (tag.empty()) {
             return;
         }
@@ -343,7 +342,7 @@ private:
     // allocation size this is always inlined, because all these do is to call
     // allocateHandleInPool()/deallocateHandleFromPool() with the right pool size.
     template<typename D>
-    HandleBase::HandleId allocateHandle() {
+    HandleBase::HandleId allocateHandle() noexcept {
         constexpr size_t BUCKET_SIZE = getBucketSize<D>();
         return allocateHandleInPool<BUCKET_SIZE>();
     }
@@ -359,7 +358,7 @@ private:
     // the code generated is not trivial (even if it's not insane either).
     template<size_t SIZE>
     UTILS_NOINLINE
-    HandleBase::HandleId allocateHandleInPool() {
+    HandleBase::HandleId allocateHandleInPool() noexcept {
         uint8_t age;
         void* p = mHandleArena.alloc(SIZE, alignof(std::max_align_t), 0, &age);
         if (UTILS_LIKELY(p)) {

filament/backend/src/AndroidNativeWindow.cpp

@@ -1,78 +0,0 @@
-/*
- * Copyright (C) 2025 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-#include "AndroidNativeWindow.h"
-
-#include <android/native_window.h>
-
-#include <utils/compiler.h>
-
-#include <cstdint>
-#include <cerrno>
-#include <utility>
-
-namespace filament::backend {
-
-std::pair<int, bool> NativeWindow::isValid(ANativeWindow* const anw) noexcept {
-    if (__builtin_available(android 28, *)) {
-        // this a proxy for is_valid()
-        auto const result = ANativeWindow_getBuffersDataSpace(anw);
-        return { result, result >= 0 };
-    }
-    // fallback on using private APIs
-    NativeWindow const* pWindow = reinterpret_cast<NativeWindow const*>(anw);
-    if (UTILS_LIKELY(pWindow->query)) {
-        int isValid = 0;
-        int const err = pWindow->query(anw, IS_VALID, &isValid);
-        return { err, bool(isValid) };
-    }
-    return { -EINVAL, false };
-}
-
-int NativeWindow::getNextFrameId(ANativeWindow* anw, uint64_t* frameId) {
-    NativeWindow const* pWindow = reinterpret_cast<NativeWindow const*>(anw);
-    return pWindow->perform(anw, GET_NEXT_FRAME_ID, frameId);
-}
-
-int NativeWindow::enableFrameTimestamps(ANativeWindow* anw, bool enable) {
-    NativeWindow const* pWindow = reinterpret_cast<NativeWindow const*>(anw);
-    return pWindow->perform(anw, ENABLE_FRAME_TIMESTAMPS, enable);
-}
-
-int NativeWindow::getCompositorTiming(ANativeWindow* anw,
-        int64_t* compositeDeadline, int64_t* compositeInterval,
-        int64_t* compositeToPresentLatency) {
-    NativeWindow const* pWindow = reinterpret_cast<NativeWindow const*>(anw);
-    return pWindow->perform(anw, GET_COMPOSITOR_TIMING,
-            compositeDeadline, compositeInterval, compositeToPresentLatency);
-}
-
-int NativeWindow::getFrameTimestamps(ANativeWindow* anw,
-        uint64_t frameId,
-        int64_t* outRequestedPresentTime, int64_t* outAcquireTime,
-        int64_t* outLatchTime, int64_t* outFirstRefreshStartTime,
-        int64_t* outLastRefreshStartTime, int64_t* outGpuCompositionDoneTime,
-        int64_t* outDisplayPresentTime, int64_t* outDequeueReadyTime,
-        int64_t* outReleaseTime) {
-    NativeWindow const* pWindow = reinterpret_cast<NativeWindow const*>(anw);
-    return pWindow->perform(anw, GET_FRAME_TIMESTAMPS,
-            frameId, outRequestedPresentTime, outAcquireTime, outLatchTime,
-            outFirstRefreshStartTime, outLastRefreshStartTime,
-            outGpuCompositionDoneTime, outDisplayPresentTime,
-            outDequeueReadyTime, outReleaseTime);
-}
-
-} // namespace filament::backend

filament/backend/src/AndroidNativeWindow.h

@@ -1,63 +0,0 @@
-/*
- * 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 FILAMENT_BACKEND_ANDROIDNATIVEWINDOW_H
-#define FILAMENT_BACKEND_ANDROIDNATIVEWINDOW_H
-
-#include <android/native_window.h>
-
-#include <cstdint>
-#include <utility>
-
-namespace filament::backend {
-
-struct NativeWindow {
-    // this class can't be instantiated. It's used by casting ANativeWindow* to it.
-    NativeWindow() noexcept = delete;
-    ~NativeWindow() noexcept = delete;
-
-    // is valid query enum value
-    enum {
-        IS_VALID                = 17,
-        GET_NEXT_FRAME_ID       = 24,
-        ENABLE_FRAME_TIMESTAMPS = 25,
-        GET_COMPOSITOR_TIMING   = 26,
-        GET_FRAME_TIMESTAMPS    = 27,
-    };
-    uint64_t pad[18];
-    int (*query)(ANativeWindow const*, int, int*);
-    int (*perform)(ANativeWindow*, int, ...);
-
-    // return whether the ANativeWindow is valid
-    static std::pair<int, bool> isValid(ANativeWindow* anw) noexcept;
-
-    static int getNextFrameId(ANativeWindow* anw, uint64_t* frameId);
-    static int enableFrameTimestamps(ANativeWindow* anw, bool enable);
-    static int getCompositorTiming(ANativeWindow* anw,
-            int64_t* compositeDeadline, int64_t* compositeInterval,
-            int64_t* compositeToPresentLatency);
-    static int getFrameTimestamps(ANativeWindow* anw,
-            uint64_t frameId,
-            int64_t* outRequestedPresentTime, int64_t* outAcquireTime,
-            int64_t* outLatchTime, int64_t* outFirstRefreshStartTime,
-            int64_t* outLastRefreshStartTime, int64_t* outGpuCompositionDoneTime,
-            int64_t* outDisplayPresentTime, int64_t* outDequeueReadyTime,
-            int64_t* outReleaseTime);
-};
-
-} // namespace filament::backend
-
-#endif //FILAMENT_BACKEND_ANDROIDNATIVEWINDOW_H

filament/backend/src/AndroidSwapChainHelper.cpp

@@ -1,63 +0,0 @@
-/*
- * Copyright (C) 2025 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-#include "AndroidSwapChainHelper.h"
-#include "AndroidNativeWindow.h"
-
-#include <android/native_window.h>
-
-#include <cstddef>
-#include <cstdint>
-#include <limits>
-#include <mutex>
-
-namespace filament::backend {
-
-AndroidSwapChainHelper::AndroidSwapChainHelper() = default;
-
-AndroidSwapChainHelper::~AndroidSwapChainHelper() noexcept = default;
-
-bool AndroidSwapChainHelper::setPresentFrameId(
-        ANativeWindow* anw, uint64_t frameId) const noexcept {
-    uint64_t sysFrameId{};
-    int const status = NativeWindow::getNextFrameId(anw, &sysFrameId);
-    if (status == 0) {
-        std::lock_guard const lock(mLock);
-        auto const pos = mFrameIdToSystemFrameId.find(frameId);
-        if (pos != mFrameIdToSystemFrameId.end() && pos->second != sysFrameId) {
-            // we're trying to associate the same frame id to a different frame!
-            return false;
-        }
-        // make space by destroying the oldest entry
-        if (mFrameIdToSystemFrameId.size() >= MAX_HISTORY_SIZE) {
-            mFrameIdToSystemFrameId.erase(mFrameIdToSystemFrameId.begin());
-        }
-        mFrameIdToSystemFrameId.insert(mFrameIdToSystemFrameId.end(), { frameId, sysFrameId });
-        return true;
-    }
-    return false;
-}
-
-uint64_t AndroidSwapChainHelper::getFrameId(uint64_t frameId) const noexcept {
-    std::lock_guard const lock(mLock);
-    auto pos = mFrameIdToSystemFrameId.find(frameId);
-    if (pos != mFrameIdToSystemFrameId.end()) {
-        return pos->second;
-    }
-    return std::numeric_limits<uint64_t>::max();
-}
-
-}

filament/backend/src/AndroidSwapChainHelper.h

@@ -1,47 +0,0 @@
-/*
- * 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_ANDROIDSWAPCHAINHELPER_H
-#define TNT_FILAMENT_BACKEND_ANDROIDSWAPCHAINHELPER_H
-
-#include <utils/Mutex.h>
-
-#include <android/native_window.h>
-
-#include <map>
-
-#include <cstddef>
-#include <cstdint>
-
-namespace filament::backend {
-
-struct AndroidSwapChainHelper {
-    AndroidSwapChainHelper();
-    ~AndroidSwapChainHelper() noexcept;
-
-    // methods below are thread-safe
-    bool setPresentFrameId(ANativeWindow* anw, uint64_t frameId) const noexcept;
-    uint64_t getFrameId(uint64_t frameId) const noexcept;
-
-private:
-    static constexpr size_t MAX_HISTORY_SIZE = 32;
-    mutable utils::Mutex mLock; // very low-contention lock
-    mutable std::map<uint64_t, uint64_t> mFrameIdToSystemFrameId{};
-};
-
-}
-
-#endif //TNT_FILAMENT_BACKEND_ANDROIDSWAPCHAINHELPER_H

filament/backend/src/BackendUtils.cpp

@@ -18,16 +18,10 @@
 
 #include "DataReshaper.h"
 
-#include <backend/PixelBufferDescriptor.h>
 #include <backend/DriverEnums.h>
 
-#include <utils/BitmaskEnum.h>
-#include <utils/compiler.h>
 #include <utils/CString.h>
 
-#include <cstddef>
-#include <cstdint>
-#include <utility>
 #include <string_view>
 
 namespace filament::backend {
@@ -642,7 +636,7 @@ bool reshape(const PixelBufferDescriptor& data, PixelBufferDescriptor& reshaped)
     switch (data.type) {
         case PixelDataType::BYTE:
         case PixelDataType::UBYTE: {
-            uint8_t* bytes = static_cast<uint8_t*>(malloc(reshapedSize));
+            uint8_t* bytes = (uint8_t*) malloc(reshapedSize);
             DataReshaper::reshape<uint8_t, 3, 4>(bytes, data.buffer, data.size);
             PixelBufferDescriptor pbd(bytes, reshapedSize, reshapedFormat, data.type,
                     data.alignment, data.left, data.top, data.stride, freeFunc);
@@ -652,7 +646,7 @@ bool reshape(const PixelBufferDescriptor& data, PixelBufferDescriptor& reshaped)
         case PixelDataType::SHORT:
         case PixelDataType::USHORT:
         case PixelDataType::HALF: {
-            uint8_t* bytes = static_cast<uint8_t*>(malloc(reshapedSize));
+            uint8_t* bytes = (uint8_t*) malloc(reshapedSize);
             DataReshaper::reshape<uint16_t, 3, 4>(bytes, data.buffer, data.size);
             PixelBufferDescriptor pbd(bytes, reshapedSize, reshapedFormat, data.type,
                     data.alignment, data.left, data.top, data.stride, freeFunc);
@@ -661,7 +655,7 @@ bool reshape(const PixelBufferDescriptor& data, PixelBufferDescriptor& reshaped)
         }
         case PixelDataType::INT:
         case PixelDataType::UINT: {
-            uint8_t* bytes = static_cast<uint8_t*>(malloc(reshapedSize));
+            uint8_t* bytes = (uint8_t*) malloc(reshapedSize);
             DataReshaper::reshape<uint32_t, 3, 4>(bytes, data.buffer, data.size);
             PixelBufferDescriptor pbd(bytes, reshapedSize, reshapedFormat, data.type,
                     data.alignment, data.left, data.top, data.stride, freeFunc);
@@ -669,7 +663,7 @@ bool reshape(const PixelBufferDescriptor& data, PixelBufferDescriptor& reshaped)
             return true;
         }
         case PixelDataType::FLOAT: {
-            uint8_t* bytes = static_cast<uint8_t*>(malloc(reshapedSize));
+            uint8_t* bytes = (uint8_t*) malloc(reshapedSize);
             DataReshaper::reshape<float, 3, 4>(bytes, data.buffer, data.size);
             PixelBufferDescriptor pbd(bytes, reshapedSize, reshapedFormat, data.type,
                     data.alignment, data.left, data.top, data.stride, freeFunc);

filament/backend/src/CallbackManager.cpp

@@ -20,7 +20,7 @@
 
 namespace filament::backend {
 
-CallbackManager::CallbackManager(DriverBase& driver)
+CallbackManager::CallbackManager(DriverBase& driver) noexcept
     : mDriver(driver), mCallbacks(1) {
 }
 

filament/backend/src/CallbackManager.h

@@ -51,7 +51,7 @@ class CallbackManager {
 public:
     using Handle = Container::const_iterator;
 
-    explicit CallbackManager(DriverBase& driver);
+    explicit CallbackManager(DriverBase& driver) noexcept;
 
     ~CallbackManager() noexcept;
 
@@ -78,7 +78,7 @@ private:
         return --mCallbacks.end();
     }
 
-    Container::iterator allocateNewSlot() {
+    Container::iterator allocateNewSlot() noexcept {
         std::lock_guard const lock(mLock);
         auto curr = --mCallbacks.end();
         mCallbacks.emplace_back();

filament/backend/src/CommandStream.cpp

@@ -57,15 +57,12 @@ static void printParameterPack(io::ostream& out, const FIRST& first, const REMAI
     printParameterPack(out, rest...);
 }
 
-static UTILS_NOINLINE UTILS_UNUSED std::string_view extractMethodName(std::string_view command) noexcept { // NOLINT(*-exception-escape)
-    constexpr char startPattern[] = "::Command<&filament::backend::Driver::";
+static UTILS_NOINLINE UTILS_UNUSED std::string_view extractMethodName(std::string_view command) noexcept {
+    constexpr const char startPattern[] = "::Command<&filament::backend::Driver::";
     auto pos = command.rfind(startPattern);
     auto end = command.rfind('(');
     pos += sizeof(startPattern) - 1;
-    if (pos > command.size()) {
-        return { command.data(), command.size() };
-    }
-    return command.substr(pos, end-pos); // this can't throw by construction
+    return command.substr(pos, end-pos);
 }
 
 // ------------------------------------------------------------------------------------------------

filament/backend/src/CompilerThreadPool.cpp

@@ -18,14 +18,7 @@
 
 #include <private/utils/Tracing.h>
 
-#include <utils/compiler.h>
-#include <utils/debug.h>
-
-#include <algorithm>
-#include <iterator>
 #include <memory>
-#include <mutex>
-#include <utility>
 
 namespace filament::backend {
 
@@ -43,7 +36,7 @@ CompilerThreadPool::~CompilerThreadPool() noexcept {
 }
 
 void CompilerThreadPool::init(uint32_t threadCount,
-        ThreadSetup&& threadSetup, ThreadCleanup&& threadCleanup) {
+        ThreadSetup&& threadSetup, ThreadCleanup&& threadCleanup) noexcept {
     auto setup = std::make_shared<ThreadSetup>(std::move(threadSetup));
     auto cleanup = std::make_shared<ThreadCleanup>(std::move(threadCleanup));
 

filament/backend/src/CompilerThreadPool.h

@@ -47,7 +47,8 @@ public:
     using Job = utils::Invocable<void()>;
     using ThreadSetup = utils::Invocable<void()>;
     using ThreadCleanup = utils::Invocable<void()>;
-    void init(uint32_t threadCount, ThreadSetup&& threadSetup, ThreadCleanup&& threadCleanup);
+    void init(uint32_t threadCount,
+            ThreadSetup&& threadSetup, ThreadCleanup&& threadCleanup) noexcept;
     void terminate() noexcept;
     void queue(CompilerPriorityQueue priorityQueue, program_token_t const& token, Job&& job);
     Job dequeue(program_token_t const& token);

filament/backend/src/DataReshaper.h

@@ -63,7 +63,6 @@ public:
     static void copyImage(uint8_t* UTILS_RESTRICT dest,
                           const uint8_t* UTILS_RESTRICT src,
                           size_t srcBytesPerRow, size_t /*srcChannelCount*/,
-                          size_t /*dstRowOffset */, size_t /*dstColumnOffset */,
                           size_t dstBytesPerRow, size_t /*dstChannelCount*/,
                           size_t /*width*/, size_t height, bool /*swizzle*/) {
         if (srcBytesPerRow == dstBytesPerRow) {
@@ -80,20 +79,17 @@ public:
     template<typename dstComponentType, typename srcComponentType>
     static void reshapeImage(uint8_t* UTILS_RESTRICT dest, const uint8_t* UTILS_RESTRICT src,
             size_t srcBytesPerRow,
-            size_t srcChannelCount,
-            size_t dstRowOffset, size_t dstColumnOffset,
-            size_t dstBytesPerRow, size_t dstChannelCount,
+            size_t srcChannelCount, size_t dstBytesPerRow, size_t dstChannelCount,
             size_t width, size_t height, bool swizzle) {
         const dstComponentType dstMaxValue = getMaxValue<dstComponentType>();
         const srcComponentType srcMaxValue = getMaxValue<srcComponentType>();
         const size_t minChannelCount = math::min(srcChannelCount, dstChannelCount);
         assert_invariant(minChannelCount <= 4);
         UTILS_ASSUME(minChannelCount <= 4);
-        dest += (dstRowOffset * dstBytesPerRow);
         const int inds[4] = { swizzle ? 2 : 0, 1, swizzle ? 0 : 2, 3 };
         for (size_t row = 0; row < height; ++row) {
-            const srcComponentType* in = (const srcComponentType*) src;
-            dstComponentType* out = (dstComponentType*)dest + (dstColumnOffset * dstChannelCount);
+            const srcComponentType* in = (const srcComponentType*)src;
+            dstComponentType* out = (dstComponentType*)dest;
             for (size_t column = 0; column < width; ++column) {
                 for (size_t channel = 0; channel < minChannelCount; ++channel) {
                     if constexpr (std::is_same_v<dstComponentType, srcComponentType>) {
@@ -132,23 +128,17 @@ public:
             default: return false;
         }
         void (*reshaper)(uint8_t* dest, const uint8_t* src, size_t srcBytesPerRow,
-                size_t srcChannelCount,
-                size_t srcRowOffset, size_t srcColumnOffset,
-                size_t dstBytesPerRow, size_t dstChannelCount,
+                size_t srcChannelCount, size_t dstBytesPerRow, size_t dstChannelCount,
                 size_t width, size_t height, bool swizzle) = nullptr;
-        constexpr auto UBYTE = PixelDataType::UBYTE;
-        constexpr auto FLOAT = PixelDataType::FLOAT;
-        constexpr auto UINT = PixelDataType::UINT;
-        constexpr auto INT = PixelDataType::INT;
-        constexpr auto HALF = PixelDataType::HALF;
+        constexpr auto UBYTE = PixelDataType::UBYTE, FLOAT = PixelDataType::FLOAT,
+                UINT = PixelDataType::UINT, INT = PixelDataType::INT;
         switch (dst->type) {
             case UBYTE:
                 switch (srcType) {
                     case UBYTE:
                         reshaper = reshapeImage<uint8_t, uint8_t>;
                         if (dst->format == PixelDataFormat::RGBA &&
-                                dstChannelCount == srcChannelCount && !swizzle && dst->top == 0 &&
-                                dst->left == 0) {
+                                dstChannelCount == srcChannelCount && !swizzle) {
                             reshaper = copyImage;
                         }
                         break;
@@ -185,20 +175,13 @@ public:
                     default: return false;
                 }
                 break;
-            case HALF:
-                switch (srcType) {
-                    case HALF: reshaper = copyImage; break;
-                    default: return false;
-                }
-                break;
             default:
                 return false;
         }
         uint8_t* dstBytes = (uint8_t*) dst->buffer;
         const int dstBytesPerRow = PixelBufferDescriptor::computeDataSize(dst->format, dst->type,
                 dst->stride ? dst->stride : width, 1, dst->alignment);
-        reshaper(dstBytes, srcBytes, srcBytesPerRow, srcChannelCount,
-                dst->top, dst->left, dstBytesPerRow,
+        reshaper(dstBytes, srcBytes, srcBytesPerRow, srcChannelCount, dstBytesPerRow,
                 dstChannelCount, width, height, swizzle);
         return true;
     }

filament/backend/src/Driver.cpp

@@ -131,7 +131,7 @@ void DriverBase::purge() noexcept {
 
 // ------------------------------------------------------------------------------------------------
 
-void DriverBase::scheduleDestroySlow(BufferDescriptor&& buffer) {
+void DriverBase::scheduleDestroySlow(BufferDescriptor&& buffer) noexcept {
     auto const handler = buffer.getHandler();
     scheduleCallback(handler, [buffer = std::move(buffer)]() {
         // user callback is called when BufferDescriptor gets destroyed
@@ -140,7 +140,7 @@ void DriverBase::scheduleDestroySlow(BufferDescriptor&& buffer) {
 
 // This is called from an async driver method so it's in the GL thread, but purge is called
 // on the user thread. This is typically called 0 or 1 times per frame.
-void DriverBase::scheduleRelease(AcquiredImage const& image) {
+void DriverBase::scheduleRelease(AcquiredImage const& image) noexcept {
     scheduleCallback(image.handler, [callback = image.callback, image = image.image, userData = image.userData]() {
         callback(image, userData);
     });

filament/backend/src/DriverBase.h

@@ -78,9 +78,6 @@ struct HwBufferObject : public HwBase {
     explicit HwBufferObject(uint32_t byteCount) noexcept : byteCount(byteCount) {}
 };
 
-struct HwMemoryMappedBuffer : public HwBase {
-};
-
 struct HwIndexBuffer : public HwBase {
     uint32_t count : 27;
     uint32_t elementSize : 5;
@@ -214,15 +211,15 @@ public:
 protected:
     class CallbackDataDetails;
 
-    void scheduleDestroy(BufferDescriptor&& buffer) {
+    inline void scheduleDestroy(BufferDescriptor&& buffer) noexcept {
         if (buffer.hasCallback()) {
             scheduleDestroySlow(std::move(buffer));
         }
     }
 
-    void scheduleDestroySlow(BufferDescriptor&& buffer);
+    void scheduleDestroySlow(BufferDescriptor&& buffer) noexcept;
 
-    void scheduleRelease(AcquiredImage const& image);
+    void scheduleRelease(AcquiredImage const& image) noexcept;
 
     void debugCommandBegin(CommandStream* cmds, bool synchronous, const char* methodName) noexcept override;
     void debugCommandEnd(CommandStream* cmds, bool synchronous, const char* methodName) noexcept override;

filament/backend/src/HandleAllocator.cpp

@@ -81,19 +81,19 @@ HandleAllocator<P0, P1, P2>::Allocator::Allocator(AreaPolicy::HeapArea const& ar
 template <size_t P0, size_t P1, size_t P2>
 HandleAllocator<P0, P1, P2>::HandleAllocator(const char* name, size_t size,
         bool disableUseAfterFreeCheck,
-        bool disableHeapHandleTags)
+        bool disableHeapHandleTags) noexcept
     : mHandleArena(name, size, disableUseAfterFreeCheck),
       mUseAfterFreeCheckDisabled(disableUseAfterFreeCheck),
       mHeapHandleTagsDisabled(disableHeapHandleTags) {
 }
 
 template <size_t P0, size_t P1, size_t P2>
-HandleAllocator<P0, P1, P2>::HandleAllocator(const char* name, size_t size)
+HandleAllocator<P0, P1, P2>::HandleAllocator(const char* name, size_t size) noexcept
     : HandleAllocator(name, size, false, false) {
 }
 
 template <size_t P0, size_t P1, size_t P2>
-HandleAllocator<P0, P1, P2>::~HandleAllocator() noexcept {
+HandleAllocator<P0, P1, P2>::~HandleAllocator() {
     auto& overflowMap = mOverflowMap;
     if (!overflowMap.empty()) {
         PANIC_LOG("Not all handles have been freed. Probably leaking memory.");
@@ -156,7 +156,7 @@ void HandleAllocator<P0, P1, P2>::deallocateHandleSlow(HandleBase::HandleId id,
 
 template<size_t P0, size_t P1, size_t P2>
 UTILS_NOINLINE
-ImmutableCString HandleAllocator<P0, P1, P2>::getHandleTag(HandleBase::HandleId id) const noexcept {
+CString HandleAllocator<P0, P1, P2>::getHandleTag(HandleBase::HandleId id) const noexcept {
     uint32_t key = id;
     if (UTILS_LIKELY(isPoolHandle(id))) {
         // Truncate the age to get the debug tag
@@ -172,7 +172,7 @@ DebugTag::DebugTag() {
 }
 
 UTILS_NOINLINE
-ImmutableCString DebugTag::findHandleTag(HandleBase::HandleId key) const noexcept {
+CString DebugTag::findHandleTag(HandleBase::HandleId key) const noexcept {
     std::unique_lock const lock(mDebugTagLock);
     if (auto pos = mDebugTags.find(key); pos != mDebugTags.end()) {
         return pos->second;
@@ -181,7 +181,7 @@ ImmutableCString DebugTag::findHandleTag(HandleBase::HandleId key) const noexcep
 }
 
 UTILS_NOINLINE
-void DebugTag::writePoolHandleTag(HandleBase::HandleId key, ImmutableCString&& tag) noexcept {
+void DebugTag::writePoolHandleTag(HandleBase::HandleId key, CString&& tag) noexcept {
     // This line is the costly part. In the future, we could potentially use a custom
     // allocator.
     std::unique_lock const lock(mDebugTagLock);
@@ -190,7 +190,7 @@ void DebugTag::writePoolHandleTag(HandleBase::HandleId key, ImmutableCString&& t
 }
 
 UTILS_NOINLINE
-void DebugTag::writeHeapHandleTag(HandleBase::HandleId key, ImmutableCString&& tag) noexcept {
+void DebugTag::writeHeapHandleTag(HandleBase::HandleId key, CString&& tag) noexcept {
     // This line is the costly part. In the future, we could potentially use a custom
     // allocator.
     std::unique_lock const lock(mDebugTagLock);

filament/backend/src/Platform.cpp

@@ -122,22 +122,6 @@ bool Platform::pumpEvents() noexcept {
     return false;
 }
 
-bool Platform::isCompositorTimingSupported() const noexcept {
-    return false;
-}
-
-bool Platform::queryCompositorTiming(SwapChain const*, CompositorTiming*) const noexcept {
-    return false;
-}
-
-bool Platform::setPresentFrameId(SwapChain const*, uint64_t) noexcept {
-    return false;
-}
-
-bool Platform::queryFrameTimestamps(SwapChain const*, uint64_t, FrameTimestamps*) const noexcept {
-    return false;
-}
-
 void Platform::setBlobFunc(InsertBlobFunc&& insertBlob, RetrieveBlobFunc&& retrieveBlob) noexcept {
     mInsertBlob = std::move(insertBlob);
     mRetrieveBlob = std::move(retrieveBlob);

filament/backend/src/Program.cpp

@@ -41,37 +41,37 @@ Program& Program::operator=(Program&& rhs) noexcept = default;
 
 Program::~Program() noexcept = default;
 
-Program& Program::priorityQueue(CompilerPriorityQueue const priorityQueue) noexcept {
+Program& Program::priorityQueue(CompilerPriorityQueue priorityQueue) noexcept {
     mPriorityQueue = priorityQueue;
     return *this;
 }
 
 Program& Program::diagnostics(CString const& name,
-        Invocable<io::ostream&(CString const& name, io::ostream&)>&& logger) {
+        Invocable<io::ostream&(utils::CString const& name, io::ostream&)>&& logger) {
     mName = name;
     mLogger = std::move(logger);
     return *this;
 }
 
-Program& Program::shader(ShaderStage shader, void const* data, size_t const size) {
+Program& Program::shader(ShaderStage shader, void const* data, size_t size) {
     ShaderBlob blob(size);
     std::copy_n((const uint8_t *)data, size, blob.data());
     mShadersSource[size_t(shader)] = std::move(blob);
     return *this;
 }
 
-Program& Program::shaderLanguage(ShaderLanguage const shaderLanguage) {
+Program& Program::shaderLanguage(ShaderLanguage shaderLanguage) {
     mShaderLanguage = shaderLanguage;
     return *this;
 }
 
-Program& Program::descriptorBindings(descriptor_set_t const set,
+Program& Program::descriptorBindings(backend::descriptor_set_t set,
         DescriptorBindingsInfo descriptorBindings) noexcept {
     mDescriptorBindings[set] = std::move(descriptorBindings);
     return *this;
 }
 
-Program& Program::uniforms(uint32_t index, CString name, UniformInfo uniforms) {
+Program& Program::uniforms(uint32_t index, utils::CString name, UniformInfo uniforms) noexcept {
     mBindingUniformsInfo.reserve(mBindingUniformsInfo.capacity() + 1);
     mBindingUniformsInfo.emplace_back(index, std::move(name), std::move(uniforms));
     return *this;
@@ -88,17 +88,17 @@ Program& Program::specializationConstants(SpecializationConstantsInfo specConsta
 }
 
 Program& Program::pushConstants(ShaderStage stage,
-        FixedCapacityVector<PushConstant> constants) noexcept {
+        utils::FixedCapacityVector<PushConstant> constants) noexcept {
     mPushConstants[static_cast<uint8_t>(stage)] = std::move(constants);
     return *this;
 }
 
-Program& Program::cacheId(uint64_t const cacheId) noexcept {
+Program& Program::cacheId(uint64_t cacheId) noexcept {
     mCacheId = cacheId;
     return *this;
 }
 
-Program& Program::multiview(bool const multiview) noexcept {
+Program& Program::multiview(bool multiview) noexcept {
     mMultiview = multiview;
     return *this;
 }

filament/backend/src/metal/MetalBuffer.h

@@ -18,8 +18,6 @@
 #define TNT_FILAMENT_DRIVER_METALBUFFER_H
 
 #include "MetalContext.h"
-#include "MetalFlags.h"
-#include "MetalUtils.h"
 
 #include <backend/DriverEnums.h>
 #include <backend/platforms/PlatformMetal.h>
@@ -155,7 +153,7 @@ private:
     Type mType = Type::NONE;
 
     static PlatformMetal* platform;
-    static std::array<uint64_t, TypeCount> aliveBuffers;
+    static std::array<std::atomic<uint64_t>, TypeCount> aliveBuffers;
 };
 
 class MetalBuffer {
@@ -193,15 +191,6 @@ public:
 
     void* getCpuBuffer() const noexcept { return mCpuBuffer; }
 
-    void setLabel(const utils::ImmutableCString& label) {
-#if FILAMENT_METAL_DEBUG_LABELS
-        if (label.empty()) {
-            return;
-        }
-        mBuffer.get().label = @(label.c_str_safe());
-#endif
-    }
-
     enum Stage : uint8_t {
         VERTEX      = 1u << 0u,
         FRAGMENT    = 1u << 1u,
@@ -261,8 +250,18 @@ public:
     // In practice, MetalRingBuffer is used for argument buffers, which are kept in the constant
     // address space. Constant buffers have specific alignment requirements when specifying an
     // offset.
+#if defined(FILAMENT_IOS)
+#if TARGET_OS_SIMULATOR
+    // The iOS simulator has differing alignment requirements.
+    static constexpr auto METAL_CONSTANT_BUFFER_OFFSET_ALIGNMENT = 256;
+#else
+    static constexpr auto METAL_CONSTANT_BUFFER_OFFSET_ALIGNMENT = 4;
+#endif  // TARGET_OS_SIMULATOR
+#else
+    static constexpr auto METAL_CONSTANT_BUFFER_OFFSET_ALIGNMENT = 32;
+#endif
     static inline auto computeSlotSize(MTLSizeAndAlign layout) {
-         return align(align(layout.size, layout.align), getUniformBufferOffsetAlignment());
+         return align(align(layout.size, layout.align), METAL_CONSTANT_BUFFER_OFFSET_ALIGNMENT);
     }
 
     MetalRingBuffer(id<MTLDevice> device, MTLResourceOptions options, MTLSizeAndAlign layout,

filament/backend/src/metal/MetalBuffer.mm

@@ -24,7 +24,7 @@
 namespace filament {
 namespace backend {
 
-std::array<uint64_t, TrackedMetalBuffer::TypeCount> TrackedMetalBuffer::aliveBuffers = { 0 };
+std::array<std::atomic<uint64_t>, TrackedMetalBuffer::TypeCount> TrackedMetalBuffer::aliveBuffers = { 0 };
 PlatformMetal* TrackedMetalBuffer::platform = nullptr;
 PlatformMetal* ScopedAllocationTimer::platform = nullptr;
 

filament/backend/src/metal/MetalContext.mm

@@ -95,38 +95,6 @@ void initializeSupportedGpuFamilies(MetalContext* context) {
     }
 }
 
-void logMTLCommandBufferError(MTLCommandBufferError error) {
-#define MTL_COMMAND_ERROR_CASE(ERR)                                                                \
-    if (error == (ERR)) {                                                                          \
-        LOG(ERROR) << "Filament Metal error: " #ERR ".";                                           \
-        return;                                                                                    \
-    }
-
-#if !defined(FILAMENT_IOS)
-    MTL_COMMAND_ERROR_CASE(MTLCommandBufferErrorDeviceRemoved)
-#endif
-    MTL_COMMAND_ERROR_CASE(MTLCommandBufferErrorNone)
-    MTL_COMMAND_ERROR_CASE(MTLCommandBufferErrorInternal)
-    MTL_COMMAND_ERROR_CASE(MTLCommandBufferErrorTimeout)
-    MTL_COMMAND_ERROR_CASE(MTLCommandBufferErrorPageFault)
-    MTL_COMMAND_ERROR_CASE(MTLCommandBufferErrorAccessRevoked)
-    MTL_COMMAND_ERROR_CASE(MTLCommandBufferErrorNotPermitted)
-    MTL_COMMAND_ERROR_CASE(MTLCommandBufferErrorOutOfMemory)
-    MTL_COMMAND_ERROR_CASE(MTLCommandBufferErrorInvalidResource)
-
-    if (@available(macOS 11.0, *)) {
-        MTL_COMMAND_ERROR_CASE(MTLCommandBufferErrorMemoryless)
-    }
-
-    if (@available(iOS 15.0, macOS 12.0, *)) {
-        MTL_COMMAND_ERROR_CASE(MTLCommandBufferErrorStackOverflow)
-    }
-
-    LOG(ERROR) << "Filament Metal unknown error.";
-
-#undef MTL_COMMAND_ERROR_CASE
-}
-
 id<MTLCommandBuffer> getPendingCommandBuffer(MetalContext* context) {
     if (context->pendingCommandBuffer) {
         return context->pendingCommandBuffer;
@@ -134,7 +102,7 @@ id<MTLCommandBuffer> getPendingCommandBuffer(MetalContext* context) {
     context->pendingCommandBuffer = [context->commandQueue commandBuffer];
     // It's safe for this block to capture the context variable. MetalDriver::terminate will ensure
     // all frames and their completion handlers finish before context is deallocated.
-    const uint64_t thisCommandBufferId = context->pendingCommandBufferId;
+    uint64_t thisCommandBufferId = context->pendingCommandBufferId;
     [context->pendingCommandBuffer addCompletedHandler:^(id <MTLCommandBuffer> buffer) {
         context->resourceTracker.clearResources((__bridge void*) buffer);
 
@@ -150,10 +118,6 @@ id<MTLCommandBuffer> getPendingCommandBuffer(MetalContext* context) {
                 context->memorylessLimitsReached = true;
             }
         }
-
-        if (UTILS_UNLIKELY(errorCode != MTLCommandBufferErrorNone)) {
-            logMTLCommandBufferError(errorCode);
-        }
     }];
     FILAMENT_CHECK_POSTCONDITION(context->pendingCommandBuffer)
             << "Could not obtain command buffer.";

filament/backend/src/metal/MetalDriver.h

@@ -25,9 +25,8 @@
 
 #include <backend/SamplerDescriptor.h>
 
-#include <utils/FixedCapacityVector.h>
-#include <utils/Log.h>
 #include <utils/compiler.h>
+#include <utils/Log.h>
 #include <utils/debug.h>
 
 #include <functional>
@@ -70,8 +69,7 @@ private:
     MetalContext* mContext;
 
     ShaderModel getShaderModel() const noexcept final;
-    utils::FixedCapacityVector<ShaderLanguage> getShaderLanguages(
-            ShaderLanguage preferredLanguage) const noexcept final;
+    ShaderLanguage getShaderLanguage() const noexcept final;
 
     // Overrides the default implementation by wrapping the call to fn in an @autoreleasepool block.
     void execute(std::function<void(void)> const& fn) noexcept final;

filament/backend/src/metal/MetalDriver.mm

@@ -29,7 +29,6 @@
 #include "MetalHandles.h"
 #include "MetalState.h"
 #include "MetalTimerQuery.h"
-#include "MetalUtils.h"
 
 #include <backend/platforms/PlatformMetal.h>
 #include <backend/platforms/PlatformMetal-ObjC.h>
@@ -43,7 +42,6 @@
 #include <utils/Logger.h>
 #include <utils/Panic.h>
 #include <utils/sstream.h>
-#include <utils/ImmutableCString.h>
 
 #include <algorithm>
 
@@ -420,14 +418,14 @@ void MetalDriver::finish(int) {
 }
 
 void MetalDriver::createVertexBufferInfoR(Handle<HwVertexBufferInfo> vbih, uint8_t bufferCount,
-        uint8_t attributeCount, AttributeArray attributes, utils::ImmutableCString&& tag) {
+        uint8_t attributeCount, AttributeArray attributes, utils::CString tag) {
     construct_handle<MetalVertexBufferInfo>(vbih, *mContext,
             bufferCount, attributeCount, attributes);
     mHandleAllocator.associateTagToHandle(vbih.getId(), std::move(tag));
 }
 
 void MetalDriver::createVertexBufferR(Handle<HwVertexBuffer> vbh,
-        uint32_t vertexCount, Handle<HwVertexBufferInfo> vbih, utils::ImmutableCString&& tag) {
+        uint32_t vertexCount, Handle<HwVertexBufferInfo> vbih, utils::CString tag) {
     MetalVertexBufferInfo const* const vbi = handle_cast<const MetalVertexBufferInfo>(vbih);
     construct_handle<MetalVertexBuffer>(vbh, *mContext, vertexCount, vbi->bufferCount, vbih);
     mHandleAllocator.associateTagToHandle(vbh.getId(), std::move(tag));
@@ -435,7 +433,7 @@ void MetalDriver::createVertexBufferR(Handle<HwVertexBuffer> vbh,
 }
 
 void MetalDriver::createIndexBufferR(Handle<HwIndexBuffer> ibh, ElementType elementType,
-        uint32_t indexCount, BufferUsage usage, utils::ImmutableCString&& tag) {
+        uint32_t indexCount, BufferUsage usage, utils::CString tag) {
     auto elementSize = (uint8_t)getElementTypeSize(elementType);
     auto* indexBuffer =
             construct_handle<MetalIndexBuffer>(ibh, *mContext, usage, elementSize, indexCount);
@@ -443,18 +441,16 @@ void MetalDriver::createIndexBufferR(Handle<HwIndexBuffer> ibh, ElementType elem
     FILAMENT_CHECK_POSTCONDITION(buffer.wasAllocationSuccessful())
             << "Could not allocate Metal index buffer of size " << buffer.getSize()
             << ", tag=" << tag.c_str_safe();
-    buffer.setLabel(tag);
     mHandleAllocator.associateTagToHandle(ibh.getId(), std::move(tag));
 }
 
 void MetalDriver::createBufferObjectR(Handle<HwBufferObject> boh, uint32_t byteCount,
-        BufferObjectBinding bindingType, BufferUsage usage, utils::ImmutableCString&& tag) {
+        BufferObjectBinding bindingType, BufferUsage usage, utils::CString tag) {
     auto* bufferObject =
             construct_handle<MetalBufferObject>(boh, *mContext, bindingType, usage, byteCount);
     FILAMENT_CHECK_POSTCONDITION(bufferObject->getBuffer()->wasAllocationSuccessful())
             << "Could not allocate Metal buffer of size " << byteCount
             << ", tag=" << tag.c_str_safe();
-    bufferObject->getBuffer()->setLabel(tag);
     mHandleAllocator.associateTagToHandle(boh.getId(), std::move(tag));
 }
 
@@ -490,16 +486,13 @@ inline const char* stringify(SamplerType samplerType) {
 
 void MetalDriver::createTextureR(Handle<HwTexture> th, SamplerType target, uint8_t levels,
         TextureFormat format, uint8_t samples, uint32_t width, uint32_t height,
-        uint32_t depth, TextureUsage usage, utils::ImmutableCString&& tag) {
+        uint32_t depth, TextureUsage usage, utils::CString tag) {
     // Clamp sample count to what the device supports.
     auto& sc = mContext->sampleCountLookup;
     samples = sc[std::min(MAX_SAMPLE_COUNT, samples)];
 
-    MetalTexture* texture = construct_handle<MetalTexture>(th, *mContext, target, levels, format,
-            samples, width, height, depth, usage);
-    mContext->textures.insert(texture);
-
-    texture->setLabel(tag);
+    mContext->textures.insert(construct_handle<MetalTexture>(
+            th, *mContext, target, levels, format, samples, width, height, depth, usage));
 
     DEBUG_LOG(
             "createTextureR(th = %d, target = %s, levels = %d, format = ?, samples = %d, width = "
@@ -510,22 +503,18 @@ void MetalDriver::createTextureR(Handle<HwTexture> th, SamplerType target, uint8
 }
 
 void MetalDriver::createTextureViewR(Handle<HwTexture> th, Handle<HwTexture> srch,
-        uint8_t baseLevel, uint8_t levelCount, utils::ImmutableCString&& tag) {
+        uint8_t baseLevel, uint8_t levelCount, utils::CString tag) {
     MetalTexture const* src = handle_cast<MetalTexture>(srch);
-    MetalTexture* texture =
-            construct_handle<MetalTexture>(th, *mContext, src, baseLevel, levelCount);
-    mContext->textures.insert(texture);
-    texture->setLabel(tag);
+    mContext->textures.insert(
+            construct_handle<MetalTexture>(th, *mContext, src, baseLevel, levelCount));
     mHandleAllocator.associateTagToHandle(th.getId(), std::move(tag));
 }
 
 void MetalDriver::createTextureViewSwizzleR(Handle<HwTexture> th, Handle<HwTexture> srch,
         backend::TextureSwizzle r, backend::TextureSwizzle g, backend::TextureSwizzle b,
-        backend::TextureSwizzle a, utils::ImmutableCString&& tag) {
+        backend::TextureSwizzle a, utils::CString tag) {
     MetalTexture const* src = handle_cast<MetalTexture>(srch);
-    MetalTexture* texture = construct_handle<MetalTexture>(th, *mContext, src, r, g, b, a);
-    mContext->textures.insert(texture);
-    texture->setLabel(tag);
+    mContext->textures.insert(construct_handle<MetalTexture>(th, *mContext, src, r, g, b, a));
     mHandleAllocator.associateTagToHandle(th.getId(), std::move(tag));
 }
 
@@ -533,17 +522,15 @@ void MetalDriver::createTextureExternalImage2R(Handle<HwTexture> th,
         backend::SamplerType target,
         backend::TextureFormat format,
         uint32_t width, uint32_t height, backend::TextureUsage usage,
-        Platform::ExternalImageHandleRef image, utils::ImmutableCString&& tag) {
+        Platform::ExternalImageHandleRef image, utils::CString tag) {
     // FIXME: implement createTextureExternalImage2R
 }
 
 void MetalDriver::createTextureExternalImageR(Handle<HwTexture> th, backend::SamplerType target,
         backend::TextureFormat format, uint32_t width, uint32_t height, backend::TextureUsage usage,
-        void* image, utils::ImmutableCString&& tag) {
-    MetalTexture* texture = construct_handle<MetalTexture>(th, *mContext, format, width, height,
-            usage, (CVPixelBufferRef) image);
-    mContext->textures.insert(texture);
-    texture->setLabel(tag);
+        void* image, utils::CString tag) {
+    mContext->textures.insert(construct_handle<MetalTexture>(
+            th, *mContext, format, width, height, usage, (CVPixelBufferRef)image));
     // This release matches the retain call in setupExternalImage. The MetalTexture will have
     // retained the buffer by now.
     CVPixelBufferRelease((CVPixelBufferRef)image);
@@ -552,11 +539,9 @@ void MetalDriver::createTextureExternalImageR(Handle<HwTexture> th, backend::Sam
 
 void MetalDriver::createTextureExternalImagePlaneR(Handle<HwTexture> th,
         backend::TextureFormat format, uint32_t width, uint32_t height, backend::TextureUsage usage,
-        void* image, uint32_t plane, utils::ImmutableCString&& tag) {
-    MetalTexture* texture = construct_handle<MetalTexture>(th, *mContext, format, width, height,
-            usage, (CVPixelBufferRef) image, plane);
-    mContext->textures.insert(texture);
-    texture->setLabel(tag);
+        void* image, uint32_t plane, utils::CString tag) {
+    mContext->textures.insert(construct_handle<MetalTexture>(
+            th, *mContext, format, width, height, usage, (CVPixelBufferRef)image, plane));
     // This release matches the retain call in setupExternalImage. The MetalTexture will have
     // retained the buffer by now.
     CVPixelBufferRelease((CVPixelBufferRef)image);
@@ -566,7 +551,7 @@ void MetalDriver::createTextureExternalImagePlaneR(Handle<HwTexture> th,
 void MetalDriver::importTextureR(Handle<HwTexture> th, intptr_t i,
         SamplerType target, uint8_t levels,
         TextureFormat format, uint8_t samples, uint32_t width, uint32_t height,
-        uint32_t depth, TextureUsage usage, utils::ImmutableCString&& tag) {
+        uint32_t depth, TextureUsage usage, utils::CString tag) {
     id<MTLTexture> metalTexture = (id<MTLTexture>) CFBridgingRelease((void*) i);
     FILAMENT_CHECK_PRECONDITION(metalTexture.width == width)
             << "Imported id<MTLTexture> width (" << metalTexture.width
@@ -581,22 +566,20 @@ void MetalDriver::importTextureR(Handle<HwTexture> th, intptr_t i,
     FILAMENT_CHECK_PRECONDITION(metalTexture.textureType == filamentMetalType)
             << "Imported id<MTLTexture> type (" << metalTexture.textureType
             << ") != Filament texture type (" << filamentMetalType << ")";
-    MetalTexture* texture = construct_handle<MetalTexture>(th, *mContext, target, levels, format,
-            samples, width, height, depth, usage, metalTexture);
-    mContext->textures.insert(texture);
-    texture->setLabel(tag);
+    mContext->textures.insert(construct_handle<MetalTexture>(th, *mContext,
+        target, levels, format, samples, width, height, depth, usage, metalTexture));
     mHandleAllocator.associateTagToHandle(th.getId(), std::move(tag));
 }
 
 void MetalDriver::createRenderPrimitiveR(Handle<HwRenderPrimitive> rph,
         Handle<HwVertexBuffer> vbh, Handle<HwIndexBuffer> ibh,
-        PrimitiveType pt, utils::ImmutableCString&& tag) {
+        PrimitiveType pt, utils::CString tag) {
     construct_handle<MetalRenderPrimitive>(rph);
     MetalDriver::setRenderPrimitiveBuffer(rph, pt, vbh, ibh);
     mHandleAllocator.associateTagToHandle(rph.getId(), std::move(tag));
 }
 
-void MetalDriver::createProgramR(Handle<HwProgram> rph, Program&& program, utils::ImmutableCString&& tag) {
+void MetalDriver::createProgramR(Handle<HwProgram> rph, Program&& program, utils::CString tag) {
 #if FILAMENT_METAL_DEBUG_LOG
     auto handleId = rph.getId();
     DEBUG_LOG("createProgramR(rph = %d, program = ", handleId);
@@ -606,7 +589,7 @@ void MetalDriver::createProgramR(Handle<HwProgram> rph, Program&& program, utils
     mHandleAllocator.associateTagToHandle(rph.getId(), std::move(tag));
 }
 
-void MetalDriver::createDefaultRenderTargetR(Handle<HwRenderTarget> rth, utils::ImmutableCString&& tag) {
+void MetalDriver::createDefaultRenderTargetR(Handle<HwRenderTarget> rth, utils::CString tag) {
     construct_handle<MetalRenderTarget>(rth, mContext);
     mHandleAllocator.associateTagToHandle(rth.getId(), std::move(tag));
 }
@@ -614,16 +597,14 @@ void MetalDriver::createDefaultRenderTargetR(Handle<HwRenderTarget> rth, utils::
 void MetalDriver::createRenderTargetR(Handle<HwRenderTarget> rth,
         TargetBufferFlags targetBufferFlags, uint32_t width, uint32_t height,
         uint8_t samples, uint8_t layerCount, MRT color,
-        TargetBufferInfo depth, TargetBufferInfo stencil, utils::ImmutableCString&& tag) {
+        TargetBufferInfo depth, TargetBufferInfo stencil, utils::CString tag) {
     FILAMENT_CHECK_PRECONDITION(!isInRenderPass(mContext))
             << "createRenderTarget must be called outside of a render pass.";
     // Clamp sample count to what the device supports.
     auto& sc = mContext->sampleCountLookup;
     samples = sc[std::min(MAX_SAMPLE_COUNT, samples)];
 
-    using AttachmentInfo = MetalRenderTarget::AttachmentInfo;
-
-    AttachmentInfo colorAttachments[MRT::MAX_SUPPORTED_RENDER_TARGET_COUNT] = { {} };
+    MetalRenderTarget::Attachment colorAttachments[MRT::MAX_SUPPORTED_RENDER_TARGET_COUNT] = {{}};
     for (size_t i = 0; i < MRT::MAX_SUPPORTED_RENDER_TARGET_COUNT; i++) {
         if (none(targetBufferFlags & getTargetBufferFlagsAt(i))) {
             continue;
@@ -637,7 +618,7 @@ void MetalDriver::createRenderTargetR(Handle<HwRenderTarget> rth,
         colorAttachments[i] = { colorTexture, color[i].level, color[i].layer };
     }
 
-    AttachmentInfo depthAttachment = {};
+    MetalRenderTarget::Attachment depthAttachment = {};
     if (any(targetBufferFlags & TargetBufferFlags::DEPTH)) {
         FILAMENT_CHECK_PRECONDITION(depth.handle)
                 << "The DEPTH flag was specified, but invalid depth handle provided.";
@@ -647,7 +628,7 @@ void MetalDriver::createRenderTargetR(Handle<HwRenderTarget> rth,
         depthAttachment = { depthTexture, depth.level, depth.layer };
     }
 
-    AttachmentInfo stencilAttachment = {};
+    MetalRenderTarget::Attachment stencilAttachment = {};
     if (any(targetBufferFlags & TargetBufferFlags::STENCIL)) {
         FILAMENT_CHECK_PRECONDITION(stencil.handle)
                 << "The STENCIL flag was specified, but invalid stencil handle provided.";
@@ -663,14 +644,16 @@ void MetalDriver::createRenderTargetR(Handle<HwRenderTarget> rth,
     mHandleAllocator.associateTagToHandle(rth.getId(), std::move(tag));
 }
 
-void MetalDriver::createFenceR(Handle<HwFence> fh, utils::ImmutableCString&& tag) {
+void MetalDriver::createFenceR(Handle<HwFence> fh, utils::CString tag) {
     auto* fence = handle_cast<MetalFence>(fh);
     fence->encode();
     mHandleAllocator.associateTagToHandle(fh.getId(), std::move(tag));
 }
 
 void MetalDriver::createSwapChainR(Handle<HwSwapChain> sch, void* nativeWindow, uint64_t flags,
-        utils::ImmutableCString&& tag) {
+        utils::CString tag) {
+    // TODO: support MSAA swapchain
+
     if (UTILS_UNLIKELY(flags & SWAP_CHAIN_CONFIG_APPLE_CVPIXELBUFFER)) {
         CVPixelBufferRef pixelBuffer = (CVPixelBufferRef) nativeWindow;
         construct_handle<MetalSwapChain>(sch, *mContext, mPlatform, pixelBuffer, flags);
@@ -685,18 +668,18 @@ void MetalDriver::createSwapChainR(Handle<HwSwapChain> sch, void* nativeWindow,
 }
 
 void MetalDriver::createSwapChainHeadlessR(Handle<HwSwapChain> sch,
-        uint32_t width, uint32_t height, uint64_t flags, utils::ImmutableCString&& tag) {
+        uint32_t width, uint32_t height, uint64_t flags, utils::CString tag) {
     construct_handle<MetalSwapChain>(sch, *mContext, mPlatform, width, height, flags);
     mHandleAllocator.associateTagToHandle(sch.getId(), std::move(tag));
 }
 
-void MetalDriver::createSyncR(Handle<HwSync> sh, utils::ImmutableCString&& tag) {
+void MetalDriver::createSyncR(Handle<HwSync> sh, utils::CString tag) {
     // TODO: Ensure sync is active, and then invoke and clear all pending
     // callbacks.
     mHandleAllocator.associateTagToHandle(sh.getId(), std::move(tag));
 }
 
-void MetalDriver::createTimerQueryR(Handle<HwTimerQuery> tqh, utils::ImmutableCString&& tag) {
+void MetalDriver::createTimerQueryR(Handle<HwTimerQuery> tqh, utils::CString tag) {
     // nothing to do, timer query was constructed in createTimerQueryS
     mHandleAllocator.associateTagToHandle(tqh.getId(), std::move(tag));
 }
@@ -735,12 +718,12 @@ const char* toString(DescriptorFlags flags) {
 }
 
 void MetalDriver::createDescriptorSetLayoutR(
-        Handle<HwDescriptorSetLayout> dslh, DescriptorSetLayout&& info, utils::ImmutableCString&& tag) {
+        Handle<HwDescriptorSetLayout> dslh, DescriptorSetLayout&& info, utils::CString tag) {
 #if FILAMENT_METAL_DEBUG_LOG == 1
     const char* labelStr = "";
     std::visit([&labelStr](auto&& arg) {
         using T = std::decay_t<decltype(arg)>;
-        if constexpr (std::is_same_v<T, utils::ImmutableCString> || std::is_same_v<T, utils::StaticString>) {
+        if constexpr (std::is_same_v<T, utils::CString> || std::is_same_v<T, utils::StaticString>) {
             labelStr = arg.c_str();
         }
     }, info.label);
@@ -760,11 +743,10 @@ void MetalDriver::createDescriptorSetLayoutR(
 }
 
 void MetalDriver::createDescriptorSetR(
-        Handle<HwDescriptorSet> dsh, Handle<HwDescriptorSetLayout> dslh, utils::ImmutableCString&& tag) {
+        Handle<HwDescriptorSet> dsh, Handle<HwDescriptorSetLayout> dslh, utils::CString tag) {
     DEBUG_LOG("createDescriptorSetR(dsh = %d, dslh = %d)\n", dsh.getId(), dslh.getId());
     MetalDescriptorSetLayout* layout = handle_cast<MetalDescriptorSetLayout>(dslh);
-    MetalDescriptorSet* ds = construct_handle<MetalDescriptorSet>(dsh, layout);
-    ds->setLabel(tag);
+    construct_handle<MetalDescriptorSet>(dsh, layout);
     mHandleAllocator.associateTagToHandle(dsh.getId(), std::move(tag));
 }
 
@@ -1004,19 +986,15 @@ ShaderModel MetalDriver::getShaderModel() const noexcept {
 #endif
 }
 
-utils::FixedCapacityVector<ShaderLanguage> MetalDriver::getShaderLanguages(
-        ShaderLanguage preferredLanguage) const noexcept {
-    if (preferredLanguage == backend::ShaderLanguage::MSL) {
-        return { backend::ShaderLanguage::MSL, backend::ShaderLanguage::METAL_LIBRARY };
-    }
-    return { backend::ShaderLanguage::METAL_LIBRARY, backend::ShaderLanguage::MSL };
+ShaderLanguage MetalDriver::getShaderLanguage() const noexcept {
+    return ShaderLanguage::MSL;
 }
 
-Handle<HwStream> MetalDriver::createStreamNative(void* stream, utils::ImmutableCString tag) {
+Handle<HwStream> MetalDriver::createStreamNative(void* stream, utils::CString tag) {
     return {};
 }
 
-Handle<HwStream> MetalDriver::createStreamAcquired(utils::ImmutableCString tag) {
+Handle<HwStream> MetalDriver::createStreamAcquired(utils::CString tag) {
     return {};
 }
 
@@ -1039,22 +1017,16 @@ void MetalDriver::updateStreams(DriverApi* driver) {
 
 void MetalDriver::destroyFence(Handle<HwFence> fh) {
     if (fh) {
-        auto* fence = handle_cast<MetalFence>(fh);
-        fence->cancel();
         destruct_handle<MetalFence>(fh);
     }
 }
 
 FenceStatus MetalDriver::getFenceStatus(Handle<HwFence> fh) {
-    return fenceWait(fh, 0);
-}
-
-FenceStatus MetalDriver::fenceWait(FenceHandle fh, uint64_t const timeout) {
     auto* fence = handle_cast<MetalFence>(fh);
     if (!fence) {
         return FenceStatus::ERROR;
     }
-    return fence->wait(timeout);
+    return fence->wait(0);
 }
 
 void MetalDriver::destroySync(Handle<HwSync> sh) {
@@ -1152,7 +1124,8 @@ bool MetalDriver::isSRGBSwapChainSupported() {
 }
 
 bool MetalDriver::isMSAASwapChainSupported(uint32_t) {
-    return true;
+    // TODO: support MSAA swapchain
+    return false;
 }
 
 bool MetalDriver::isProtectedContentSupported() {
@@ -1254,10 +1227,6 @@ size_t MetalDriver::getMaxArrayTextureLayers() {
     return 256;
 }
 
-size_t MetalDriver::getUniformBufferOffsetAlignment() {
-    return ::filament::backend::getUniformBufferOffsetAlignment();
-}
-
 void MetalDriver::updateIndexBuffer(Handle<HwIndexBuffer> ibh, BufferDescriptor&& data,
         uint32_t byteOffset) {
     FILAMENT_CHECK_PRECONDITION(data.buffer)
@@ -1562,9 +1531,9 @@ void MetalDriver::readPixels(Handle<HwRenderTarget> src, uint32_t x, uint32_t y,
 
     auto srcTarget = handle_cast<MetalRenderTarget>(src);
     // We always readPixels from the COLOR0 attachment.
-    MetalAttachment color = srcTarget->getDrawColorAttachment(0);
+    MetalRenderTarget::Attachment color = srcTarget->getDrawColorAttachment(0);
     id<MTLTexture> srcTexture = color.getTexture();
-    size_t miplevel = color.getLevel();
+    size_t miplevel = color.level;
 
     // Clamp height and width to actual texture's height and width
     MTLSize srcTextureSize = MTLSizeMake(srcTexture.width >> miplevel, srcTexture.height >> miplevel, 1);
@@ -1772,8 +1741,8 @@ void MetalDriver::blitDEPRECATED(TargetBufferFlags buffers,
     };
 
     // We always blit from/to the COLOR0 attachment.
-    MetalAttachment const srcColorAttachment = srcTarget->getReadColorAttachment(0);
-    MetalAttachment const dstColorAttachment = dstTarget->getDrawColorAttachment(0);
+    MetalRenderTarget::Attachment const srcColorAttachment = srcTarget->getReadColorAttachment(0);
+    MetalRenderTarget::Attachment const dstColorAttachment = dstTarget->getDrawColorAttachment(0);
 
     if (srcColorAttachment && dstColorAttachment) {
         FILAMENT_CHECK_PRECONDITION(
@@ -1785,13 +1754,13 @@ void MetalDriver::blitDEPRECATED(TargetBufferFlags buffers,
         args.filter = filter;
         args.source.region = srcTarget->getRegionFromClientRect(srcRect);
         args.source.texture = srcColorAttachment.getTexture();
-        args.source.level = srcColorAttachment.getLevel();
-        args.source.slice = srcColorAttachment.getLayer();
+        args.source.level = srcColorAttachment.level;
+        args.source.slice = srcColorAttachment.layer;
 
         args.destination.region = dstTarget->getRegionFromClientRect(dstRect);
         args.destination.texture = dstColorAttachment.getTexture();
-        args.destination.level = dstColorAttachment.getLevel();
-        args.destination.slice = dstColorAttachment.getLayer();
+        args.destination.level = dstColorAttachment.level;
+        args.destination.slice = dstColorAttachment.layer;
 
         mContext->blitter->blit(getPendingCommandBuffer(mContext), args, "blitDEPRECATED");
     }
@@ -1827,28 +1796,24 @@ void MetalDriver::bindPipeline(PipelineState const& ps) {
     auto [fragment, vertex] = functions.getRasterFunctions();
 
     // Pipeline state
-    MetalRenderTarget* const rt = mContext->currentRenderTarget;
     MTLPixelFormat colorPixelFormat[MRT::MAX_SUPPORTED_RENDER_TARGET_COUNT] = { MTLPixelFormatInvalid };
     for (size_t i = 0; i < MRT::MAX_SUPPORTED_RENDER_TARGET_COUNT; i++) {
-        const auto& attachment = rt->getDrawColorAttachment(i);
+        const auto& attachment = mContext->currentRenderTarget->getDrawColorAttachment(i);
         if (!attachment) {
             continue;
         }
         colorPixelFormat[i] = attachment.getPixelFormat();
-        assert_invariant(attachment.getSampleCount() == rt->getSampleCount());
     }
     MTLPixelFormat depthPixelFormat = MTLPixelFormatInvalid;
-    const auto& depthAttachment = rt->getDepthAttachment();
+    const auto& depthAttachment = mContext->currentRenderTarget->getDepthAttachment();
     if (depthAttachment) {
         depthPixelFormat = depthAttachment.getPixelFormat();
-        assert_invariant(depthAttachment.getSampleCount() == rt->getSampleCount());
     }
     MTLPixelFormat stencilPixelFormat = MTLPixelFormatInvalid;
-    const auto& stencilAttachment = rt->getStencilAttachment();
+    const auto& stencilAttachment = mContext->currentRenderTarget->getStencilAttachment();
     if (stencilAttachment) {
         stencilPixelFormat = stencilAttachment.getPixelFormat();
         assert_invariant(isMetalFormatStencil(stencilPixelFormat));
-        assert_invariant(stencilAttachment.getSampleCount() == rt->getSampleCount());
     }
     MetalPipelineState const pipelineState {
         .vertexFunction = vertex,
@@ -1866,7 +1831,7 @@ void MetalDriver::bindPipeline(PipelineState const& ps) {
         },
         .depthAttachmentPixelFormat = depthPixelFormat,
         .stencilAttachmentPixelFormat = stencilPixelFormat,
-        .sampleCount = rt->getSampleCount(),
+        .sampleCount = mContext->currentRenderTarget->getSamples(),
         .blendState = BlendState {
             .alphaBlendOperation = getMetalBlendOperation(rs.blendEquationAlpha),
             .rgbBlendOperation = getMetalBlendOperation(rs.blendEquationRGB),
@@ -2236,38 +2201,6 @@ void MetalDriver::executeDeferredOps() noexcept {
     }
 }
 
-MemoryMappedBufferHandle MetalDriver::mapBufferS() noexcept {
-    return alloc_handle<MetalMemoryMappedBuffer>();
-}
-
-void MetalDriver::mapBufferR(MemoryMappedBufferHandle mmbh,
-        BufferObjectHandle boh, size_t offset,
-        size_t size, MapBufferAccessFlags access, utils::ImmutableCString&& tag) {
-    construct_handle<MetalMemoryMappedBuffer>(mmbh, boh, offset, size, access);
-    mHandleAllocator.associateTagToHandle(mmbh.getId(), std::move(tag));
-}
-
-void MetalDriver::unmapBuffer(MemoryMappedBufferHandle mmbh) {
-    if (UTILS_UNLIKELY(!mmbh)) {
-        return;
-    }
-    destruct_handle<MetalMemoryMappedBuffer>(mmbh);
-}
-
-void MetalDriver::copyToMemoryMappedBuffer(MemoryMappedBufferHandle mmbh, size_t offset,
-        BufferDescriptor&& data) {
-    auto mmb = handle_cast<MetalMemoryMappedBuffer>(mmbh);
-
-    assert_invariant(any(mmb->access & MapBufferAccessFlags::WRITE_BIT));
-    assert_invariant(offset + data.size <= mmb->size);
-
-    // TODO: this isa zero-effort implementation of copyToMemoryMappedBuffer(), where we just
-    //       call updateBufferObject(). This could be a fallback implementation for when
-    //       shared memory is not available.
-    //       On UMA systems, this should just be a memcpy into the memory-mapped buffer.
-    updateBufferObject(mmb->boh, std::move(data), mmb->offset + offset);
-}
-
 // explicit instantiation of the Dispatcher
 template class ConcreteDispatcher<MetalDriver>;
 

filament/backend/src/metal/MetalHandles.h

@@ -27,7 +27,6 @@
 #include "MetalContext.h"
 #include "MetalEnums.h"
 #include "MetalExternalImage.h"
-#include "MetalFlags.h"
 #include "MetalState.h" // for MetalState::VertexDescription
 
 #include <backend/DriverEnums.h>
@@ -49,61 +48,6 @@
 namespace filament {
 namespace backend {
 
-class MetalAttachment {
-public:
-    MetalAttachment() = default;
-    MetalAttachment(id<MTLTexture> texture, uint8_t level = 0, uint16_t layer = 0)
-            : mLevel(level),
-              mLayer(layer),
-              mTexture(texture) {
-        assert_invariant(texture);
-    }
-
-    explicit operator bool() const { return mTexture != nil; }
-
-    id<MTLTexture> getTexture() const { return mTexture; }
-
-    id<MTLTexture> getMsaaTexture() const { return mMsaaTexture; }
-
-    MTLPixelFormat getPixelFormat() const {
-        return mTexture ? mTexture.pixelFormat : MTLPixelFormatInvalid;
-    }
-
-    NSUInteger getSampleCount() const {
-        if (mMsaaTexture) {
-            return mMsaaTexture.sampleCount;
-        }
-        if (mTexture) {
-            return mTexture.sampleCount;
-        }
-        return 1u;
-    }
-
-    uint8_t getLevel() const { return mLevel; }
-    uint16_t getLayer() const { return mLayer; }
-
-    MetalAttachment withMsaaTexture(id<MTLTexture> msaa) const {
-        assert_invariant(mTexture != nil);
-        assert_invariant(mTexture.sampleCount == 1u);
-        MetalAttachment result = *this;
-        result.mMsaaTexture = msaa;
-        return result;
-    }
-
-    static MetalAttachment invalidAttachment() { return MetalAttachment(); }
-
-private:
-    uint8_t mLevel = 0;
-    uint16_t mLayer = 0;
-
-    // The main texture for this Attachment. May be single-sampled or MSAA.
-    id<MTLTexture> mTexture = nil;
-
-    // The MSAA "sidecar" texture that will resolve into mTexture.
-    // If this is non-nil, mTexture must be single-sampled.
-    id<MTLTexture> mMsaaTexture = nil;
-};
-
 class MetalSwapChain : public HwSwapChain {
 public:
 
@@ -121,14 +65,14 @@ public:
 
     ~MetalSwapChain();
 
-    // Acquires a texture that can be used to render into this SwapChain and returns a
-    // MetalAttachment. The texture source depends on the type of SwapChain:
+    // Acquires a texture that can be used to render into this SwapChain.
+    // The texture source depends on the type of SwapChain:
     //   - CAMetalLayer-backed: acquires the CAMetalDrawable and returns its texture.
     //   - Headless: lazily creates and returns a headless texture.
-    // May return an invalid attachemnt if a drawable cannot be acquired.
-    MetalAttachment acquireDrawable();
-    MetalAttachment acquireDepthTexture();
-    MetalAttachment acquireStencilTexture();
+    id<MTLTexture> acquireDrawable();
+
+    id<MTLTexture> acquireDepthTexture();
+    id<MTLTexture> acquireStencilTexture();
 
     void releaseDrawable();
 
@@ -143,7 +87,6 @@ public:
 
     NSUInteger getSurfaceWidth() const;
     NSUInteger getSurfaceHeight() const;
-    NSUInteger getSampleCount() const;
 
     bool isPixelBuffer() const { return type == SwapChainType::CVPIXELBUFFERREF; }
 
@@ -162,24 +105,13 @@ private:
     void scheduleFrameScheduledCallback();
     void scheduleFrameCompletedCallback();
 
-    MetalAttachment acquireBaseDrawable();
-
-    id<MTLTexture> ensureDepthStencilTexture(uint32_t width, uint32_t height);
-    id<MTLTexture> ensureMsaaColorTexture(MTLPixelFormat format, uint32_t width, uint32_t height,
-            uint8_t samples);
-    id<MTLTexture> ensureMsaaDepthStencilTexture(MTLPixelFormat format, uint32_t width,
-            uint32_t height, uint8_t samples);
-
     static MTLPixelFormat decideDepthStencilFormat(uint64_t flags);
-    static id<MTLTexture> createMultisampledTexture(MetalContext const& context,
-            MTLPixelFormat format, uint32_t width, uint32_t height, uint8_t samples);
+    void ensureDepthStencilTexture();
 
     MetalContext& context;
     PlatformMetal& platform;
     id<CAMetalDrawable> drawable = nil;
     id<MTLTexture> depthStencilTexture = nil;
-    id<MTLTexture> msaaColor = nil;
-    id<MTLTexture> msaaDepthStencil = nil;
     id<MTLTexture> headlessDrawable = nil;
     MTLPixelFormat depthStencilFormat = MTLPixelFormatInvalid;
     NSUInteger headlessWidth = 0;
@@ -188,7 +120,6 @@ private:
     std::shared_ptr<std::mutex> layerDrawableMutex;
     MetalExternalImage externalImage;
     SwapChainType type;
-    uint64_t flags;
 
     int64_t abandonedUntilFrame = -1;
 
@@ -335,16 +266,6 @@ public:
 
     static MTLPixelFormat decidePixelFormat(MetalContext* context, TextureFormat format);
 
-    void setLabel(const utils::ImmutableCString& label) {
-#if FILAMENT_METAL_DEBUG_LABELS
-        if (label.empty()) {
-            return;
-        }
-        texture.label = @(label.c_str_safe());
-        swizzledTextureView.label = @(label.c_str_safe());
-#endif
-    }
-
     MetalContext& context;
 
     // A "sidecar" texture used to implement automatic MSAA resolve.
@@ -375,15 +296,51 @@ private:
 class MetalRenderTarget : public HwRenderTarget {
 public:
 
-    struct AttachmentInfo {
-        MetalTexture* texture = nullptr;
+    class Attachment {
+    public:
+
+        friend class MetalRenderTarget;
+
+        Attachment() = default;
+        Attachment(MetalTexture* metalTexture, uint8_t level = 0, uint16_t layer = 0) :
+                level(level), layer(layer),
+                texture(metalTexture->getMtlTextureForWrite()),
+                metalTexture(metalTexture) { }
+
+        id<MTLTexture> getTexture() const {
+            return texture;
+        }
+
+        NSUInteger getSampleCount() const {
+            return texture ? texture.sampleCount : 0u;
+        }
+
+        MTLPixelFormat getPixelFormat() const {
+            return texture ? texture.pixelFormat : MTLPixelFormatInvalid;
+        }
+
+        explicit operator bool() const {
+            return texture != nil;
+        }
+
         uint8_t level = 0;
         uint16_t layer = 0;
+
+    private:
+
+        id<MTLTexture> getMSAASidecarTexture() const {
+            // This should only be called from render targets associated with a MetalTexture.
+            assert_invariant(metalTexture);
+            return metalTexture->msaaSidecar;
+        }
+
+        id<MTLTexture> texture = nil;
+        MetalTexture* metalTexture = nullptr;
     };
 
     MetalRenderTarget(MetalContext* context, uint32_t width, uint32_t height, uint8_t samples,
-            AttachmentInfo colorAttachments[MRT::MAX_SUPPORTED_RENDER_TARGET_COUNT],
-            AttachmentInfo depthAttachment, AttachmentInfo stencilAttachment);
+            Attachment colorAttachments[MRT::MAX_SUPPORTED_RENDER_TARGET_COUNT],
+            Attachment depthAttachment, Attachment stencilAttachment);
     explicit MetalRenderTarget(MetalContext* context)
             : HwRenderTarget(0, 0), context(context), defaultRenderTarget(true) {}
 
@@ -419,14 +376,12 @@ public:
 
     math::uint2 getAttachmentSize() noexcept;
 
-    MetalAttachment getDrawColorAttachment(size_t index);
-    MetalAttachment getReadColorAttachment(size_t index);
-    MetalAttachment getDepthAttachment();
-    MetalAttachment getStencilAttachment();
+    uint8_t getSamples() const { return samples; }
 
-    // Returns the number of samples that should be used in the pipeline state that renders to this
-    // render target. Takes into account "automagic" resolve and MSAA SwapChains.
-    NSUInteger getSampleCount() const;
+    Attachment getDrawColorAttachment(size_t index);
+    Attachment getReadColorAttachment(size_t index);
+    Attachment getDepthAttachment();
+    Attachment getStencilAttachment();
 
 private:
 
@@ -436,12 +391,12 @@ private:
 
     MetalContext* context;
     bool defaultRenderTarget = false;
-
-    MetalAttachment color[MRT::MAX_SUPPORTED_RENDER_TARGET_COUNT] = {};
-    MetalAttachment depth = {};
-    MetalAttachment stencil = {};
-    math::uint2 attachmentSize = {};
     uint8_t samples = 1;
+
+    Attachment color[MRT::MAX_SUPPORTED_RENDER_TARGET_COUNT] = {};
+    Attachment depth = {};
+    Attachment stencil = {};
+    math::uint2 attachmentSize = {};
 };
 
 // MetalFence is used to implement both Fences and Syncs.
@@ -463,8 +418,6 @@ public:
     API_AVAILABLE(ios(12.0))
     void onSignal(MetalFenceSignalBlock block);
 
-    void cancel();
-
 private:
 
     MetalContext& context;
@@ -530,15 +483,6 @@ struct MetalDescriptorSet : public HwDescriptorSet {
 
     void finalize(MetalDriver* driver);
 
-    void setLabel(const utils::ImmutableCString& l) {
-#if FILAMENT_METAL_DEBUG_LABELS
-        if (l.empty()) {
-            return;
-        }
-        label = l;
-#endif
-    }
-
     id<MTLBuffer> finalizeAndGetBuffer(MetalDriver* driver, ShaderStage stage);
 
     MetalDescriptorSetLayout* layout;
@@ -561,22 +505,6 @@ struct MetalDescriptorSet : public HwDescriptorSet {
     std::vector<std::shared_ptr<MetalExternalImage>> externalImages;
 
     std::array<TrackedMetalBuffer, Program::SHADER_TYPE_COUNT> cachedBuffer = { nil };
-
-#if FILAMENT_METAL_DEBUG_LABELS
-    utils::ImmutableCString label;
-#endif
-};
-
-
-struct MetalMemoryMappedBuffer : public HwMemoryMappedBuffer {
-    MetalMemoryMappedBuffer(BufferObjectHandle boh, size_t const offset,
-            size_t const size, MapBufferAccessFlags const access)
-        : boh(boh), access(access), size(size), offset(offset) {
-    }
-    BufferObjectHandle boh{};
-    MapBufferAccessFlags access{};
-    uint32_t size = 0;
-    uint32_t offset = 0;
 };
 
 } // namespace backend

filament/backend/src/metal/MetalHandles.mm

@@ -116,8 +116,7 @@ MetalSwapChain::MetalSwapChain(
       depthStencilFormat(decideDepthStencilFormat(flags)),
       layer(nativeWindow),
       layerDrawableMutex(std::make_shared<std::mutex>()),
-      type(SwapChainType::CAMETALLAYER),
-      flags(flags) {
+      type(SwapChainType::CAMETALLAYER) {
 
     FILAMENT_CHECK_PRECONDITION([nativeWindow isKindOfClass:[CAMetalLayer class]])
             << "nativeWindow pointer of class "
@@ -148,8 +147,7 @@ MetalSwapChain::MetalSwapChain(MetalContext& context, PlatformMetal& platform, i
       depthStencilFormat(decideDepthStencilFormat(flags)),
       headlessWidth(width),
       headlessHeight(height),
-      type(SwapChainType::HEADLESS),
-      flags(flags) {}
+      type(SwapChainType::HEADLESS) {}
 
 MetalSwapChain::MetalSwapChain(MetalContext& context, PlatformMetal& platform,
         CVPixelBufferRef pixelBuffer, uint64_t flags)
@@ -157,8 +155,7 @@ MetalSwapChain::MetalSwapChain(MetalContext& context, PlatformMetal& platform,
       platform(platform),
       depthStencilFormat(decideDepthStencilFormat(flags)),
       externalImage(MetalExternalImage::createFromImage(context, pixelBuffer)),
-      type(SwapChainType::CVPIXELBUFFERREF),
-      flags(flags) {
+      type(SwapChainType::CVPIXELBUFFERREF) {
     assert_invariant(flags & SWAP_CHAIN_CONFIG_APPLE_CVPIXELBUFFER);
     MetalExternalImage::assertWritableImage(pixelBuffer);
     assert_invariant(externalImage.isValid());
@@ -170,27 +167,6 @@ MTLPixelFormat MetalSwapChain::decideDepthStencilFormat(uint64_t flags) {
                                                         : MTLPixelFormatDepth32Float;
 }
 
-id<MTLTexture> MetalSwapChain::createMultisampledTexture(MetalContext const& context,
-        MTLPixelFormat format, uint32_t width, uint32_t height, uint8_t samples) {
-    MTLTextureDescriptor* descriptor =
-            [MTLTextureDescriptor texture2DDescriptorWithPixelFormat:format
-                                                               width:width
-                                                              height:height
-                                                           mipmapped:NO];
-    descriptor.textureType = MTLTextureType2DMultisample;
-    descriptor.sampleCount = samples;
-    descriptor.usage = MTLTextureUsageRenderTarget;
-    descriptor.resourceOptions = MTLResourceStorageModePrivate;
-
-    if (context.supportsMemorylessRenderTargets) {
-        if (@available(macOS 11.0, *)) {
-            descriptor.resourceOptions = MTLResourceStorageModeMemoryless;
-        }
-    }
-
-    return [context.device newTextureWithDescriptor:descriptor];
-}
-
 MetalSwapChain::~MetalSwapChain() {
 }
 
@@ -214,18 +190,65 @@ NSUInteger MetalSwapChain::getSurfaceHeight() const {
     return (NSUInteger) layer.drawableSize.height;
 }
 
-
-NSUInteger MetalSwapChain::getSampleCount() const {
-    if (flags & flags & SwapChain::CONFIG_MSAA_4_SAMPLES) {
-        return 4u;
-    }
-    return 1u;
-}
-
 bool MetalSwapChain::isAbandoned() const {
     return context.currentFrame < abandonedUntilFrame;
 }
 
+id<MTLTexture> MetalSwapChain::acquireDrawable() {
+    if (drawable) {
+        return drawable.texture;
+    }
+
+    if (isHeadless()) {
+        if (headlessDrawable) {
+            return headlessDrawable;
+        }
+        // For headless surfaces we construct a "fake" drawable, which is simply a renderable
+        // texture.
+        MTLTextureDescriptor* textureDescriptor = [MTLTextureDescriptor new];
+        textureDescriptor.pixelFormat = MTLPixelFormatBGRA8Unorm;
+        textureDescriptor.width = headlessWidth;
+        textureDescriptor.height = headlessHeight;
+        // Specify MTLTextureUsageShaderRead so the headless surface can be blitted from.
+        textureDescriptor.usage = MTLTextureUsageRenderTarget | MTLTextureUsageShaderRead;
+#if defined(FILAMENT_IOS)
+        textureDescriptor.storageMode = MTLStorageModeShared;
+#else
+        textureDescriptor.storageMode = MTLStorageModeManaged;
+#endif
+        headlessDrawable = [context.device newTextureWithDescriptor:textureDescriptor];
+        return headlessDrawable;
+    }
+
+    if (isPixelBuffer()) {
+        return externalImage.getMtlTexture();
+    }
+
+    assert_invariant(isCaMetalLayer());
+
+    // CAMetalLayer's drawable pool is not thread safe. Use a mutex when
+    // calling -nextDrawable, or when releasing the last known reference
+    // to any CAMetalDrawable returned from a previous -nextDrawable.
+    {
+        std::lock_guard<std::mutex> lock(*layerDrawableMutex);
+        drawable = [layer nextDrawable];
+    }
+
+    if (UTILS_UNLIKELY(drawable == nil)) {
+        switch (platform.getDrawableFailureBehavior()) {
+            case PlatformMetal::DrawableFailureBehavior::PANIC:
+                FILAMENT_CHECK_POSTCONDITION(drawable != nil) << "Could not obtain drawable.";
+                break;
+
+            case PlatformMetal::DrawableFailureBehavior::ABORT_FRAME:
+                abandonedUntilFrame = context.currentFrame + 1;
+                return nil;
+        }
+    }
+
+    return drawable.texture;
+}
+
 void MetalSwapChain::releaseDrawable() {
     if (drawable) {
         std::lock_guard<std::mutex> lock(*layerDrawableMutex);
@@ -233,45 +256,32 @@ void MetalSwapChain::releaseDrawable() {
     }
 }
 
-MetalAttachment MetalSwapChain::acquireDrawable() {
-    MetalAttachment attachment = acquireBaseDrawable();
-    if (auto texture = attachment.getTexture();
-            texture && flags & SwapChain::CONFIG_MSAA_4_SAMPLES) {
-        return attachment.withMsaaTexture(
-                ensureMsaaColorTexture(texture.pixelFormat, texture.width, texture.height, 4u));
-    }
-    return attachment;
+id<MTLTexture> MetalSwapChain::acquireDepthTexture() {
+    ensureDepthStencilTexture();
+    assert_invariant(depthStencilTexture);
+    return depthStencilTexture;
 }
 
-MetalAttachment MetalSwapChain::acquireDepthTexture() {
-    MetalAttachment attachment =
-            MetalAttachment(ensureDepthStencilTexture(getSurfaceWidth(), getSurfaceHeight()));
-    if (auto texture = attachment.getTexture();
-            texture && flags & SwapChain::CONFIG_MSAA_4_SAMPLES) {
-        return attachment.withMsaaTexture(ensureMsaaDepthStencilTexture(texture.pixelFormat,
-                texture.width, texture.height, 4u));
+id<MTLTexture> MetalSwapChain::acquireStencilTexture() {
+    if (!isMetalFormatStencil(depthStencilFormat)) {
+        return nil;
     }
-    return attachment;
+    ensureDepthStencilTexture();
+    assert_invariant(depthStencilTexture);
+    return depthStencilTexture;
 }
 
-MetalAttachment MetalSwapChain::acquireStencilTexture() {
-    if (!(flags & SwapChain::CONFIG_HAS_STENCIL_BUFFER)) {
-        return MetalAttachment::invalidAttachment();
-    }
-    MetalAttachment attachment =
-            MetalAttachment(ensureDepthStencilTexture(getSurfaceWidth(), getSurfaceHeight()));
-    if (auto texture = attachment.getTexture();
-            texture && flags & SwapChain::CONFIG_MSAA_4_SAMPLES) {
-        return attachment.withMsaaTexture(ensureMsaaDepthStencilTexture(texture.pixelFormat,
-                texture.width, texture.height, 4u));
-    }
-    return attachment;
-}
-
-id<MTLTexture> MetalSwapChain::ensureDepthStencilTexture(uint32_t width, uint32_t height) {
-    if (UTILS_LIKELY(depthStencilTexture && depthStencilTexture.width == width &&
-                     depthStencilTexture.height == height)) {
-        return depthStencilTexture;
+void MetalSwapChain::ensureDepthStencilTexture() {
+    NSUInteger width = getSurfaceWidth();
+    NSUInteger height = getSurfaceHeight();
+    if (UTILS_LIKELY(depthStencilTexture)) {
+        // If the surface size has changed, we'll need to allocate a new depth/stencil texture.
+        if (UTILS_UNLIKELY(
+                    depthStencilTexture.width != width || depthStencilTexture.height != height)) {
+            depthStencilTexture = nil;
+        } else {
+            return;
+        }
     }
     MTLTextureDescriptor* descriptor =
             [MTLTextureDescriptor texture2DDescriptorWithPixelFormat:depthStencilFormat
@@ -280,36 +290,11 @@ id<MTLTexture> MetalSwapChain::ensureDepthStencilTexture(uint32_t width, uint32_
                                                            mipmapped:NO];
     descriptor.usage = MTLTextureUsageRenderTarget;
     descriptor.resourceOptions = MTLResourceStorageModePrivate;
-    return depthStencilTexture = [context.device newTextureWithDescriptor:descriptor];
-}
-
-id<MTLTexture> MetalSwapChain::ensureMsaaColorTexture(MTLPixelFormat format, uint32_t width, uint32_t height,
-        uint8_t samples) {
-    if (UTILS_LIKELY(msaaColor && msaaColor.pixelFormat == format && msaaColor.width == width &&
-                     msaaColor.height == height && msaaColor.sampleCount == samples)) {
-        return msaaColor;
-    }
-    return msaaColor = createMultisampledTexture(context, format, width, height, samples);
-}
-
-id<MTLTexture> MetalSwapChain::ensureMsaaDepthStencilTexture(MTLPixelFormat format, uint32_t width,
-        uint32_t height, uint8_t samples) {
-    if (UTILS_LIKELY(msaaDepthStencil && msaaDepthStencil.pixelFormat == format &&
-                     msaaDepthStencil.width == width && msaaDepthStencil.height == height &&
-                     msaaDepthStencil.sampleCount == samples)) {
-        return msaaDepthStencil;
-    }
-    return msaaDepthStencil = createMultisampledTexture(context, format, width, height, samples);
+    depthStencilTexture = [context.device newTextureWithDescriptor:descriptor];
 }
 
 void MetalSwapChain::setFrameScheduledCallback(
         CallbackHandler* handler, FrameScheduledCallback&& callback, uint64_t flags) {
-    if (!callback) {
-        frameScheduled.handler = nullptr;
-        frameScheduled.callback.reset();
-        frameScheduled.flags = 0;
-        return;
-    }
     frameScheduled.handler = handler;
     frameScheduled.callback = std::make_shared<FrameScheduledCallback>(std::move(callback));
     frameScheduled.flags = flags;
@@ -463,62 +448,6 @@ void MetalSwapChain::scheduleFrameCompletedCallback() {
     }];
 }
 
-MetalAttachment MetalSwapChain::acquireBaseDrawable() {
-    if (drawable) {
-        return MetalAttachment(drawable.texture);
-    }
-
-    if (isHeadless()) {
-        if (headlessDrawable) {
-            return MetalAttachment(headlessDrawable);
-        }
-        // For headless surfaces we construct a "fake" drawable, which is simply a renderable
-        // texture.
-        MTLTextureDescriptor* textureDescriptor = [MTLTextureDescriptor new];
-        textureDescriptor.pixelFormat = MTLPixelFormatBGRA8Unorm;
-        textureDescriptor.width = headlessWidth;
-        textureDescriptor.height = headlessHeight;
-        // Specify MTLTextureUsageShaderRead so the headless surface can be blitted from.
-        textureDescriptor.usage = MTLTextureUsageRenderTarget | MTLTextureUsageShaderRead;
-#if defined(FILAMENT_IOS)
-        textureDescriptor.storageMode = MTLStorageModeShared;
-#else
-        textureDescriptor.storageMode = MTLStorageModeManaged;
-#endif
-        headlessDrawable = [context.device newTextureWithDescriptor:textureDescriptor];
-        return MetalAttachment(headlessDrawable);
-    }
-
-    if (isPixelBuffer()) {
-        return MetalAttachment(externalImage.getMtlTexture());
-    }
-
-    assert_invariant(isCaMetalLayer());
-
-    // CAMetalLayer's drawable pool is not thread safe. Use a mutex when
-    // calling -nextDrawable, or when releasing the last known reference
-    // to any CAMetalDrawable returned from a previous -nextDrawable.
-    {
-        std::lock_guard<std::mutex> lock(*layerDrawableMutex);
-        drawable = [layer nextDrawable];
-    }
-
-    if (UTILS_UNLIKELY(drawable == nil)) {
-        switch (platform.getDrawableFailureBehavior()) {
-            case PlatformMetal::DrawableFailureBehavior::PANIC:
-                FILAMENT_CHECK_POSTCONDITION(drawable != nil) << "Could not obtain drawable.";
-                break;
-
-            case PlatformMetal::DrawableFailureBehavior::ABORT_FRAME:
-                abandonedUntilFrame = context.currentFrame + 1;
-                return MetalAttachment::invalidAttachment();
-        }
-    }
-
-    return MetalAttachment(drawable.texture);
-}
-
-
 MetalBufferObject::MetalBufferObject(MetalContext& context, BufferObjectBinding bindingType,
         BufferUsage usage, uint32_t byteCount)
         : HwBufferObject(byteCount), buffer(context, bindingType, usage, byteCount) {}
@@ -1035,108 +964,90 @@ void MetalTexture::loadWithBlit(uint32_t level, uint32_t slice, MTLRegion region
 }
 
 MetalRenderTarget::MetalRenderTarget(MetalContext* context, uint32_t width, uint32_t height,
-        uint8_t samples, AttachmentInfo colorAttachments[MRT::MAX_SUPPORTED_RENDER_TARGET_COUNT],
-        AttachmentInfo depthAttachment, AttachmentInfo stencilAttachment)
-        : HwRenderTarget(width, height),
-          context(context),
-          samples(samples) {
-    math::uint2 tmin = { std::numeric_limits<uint32_t>::max() };
-    UTILS_UNUSED_IN_RELEASE math::uint2 tmax = { 0 };
+        uint8_t samples, Attachment colorAttachments[MRT::MAX_SUPPORTED_RENDER_TARGET_COUNT],
+        Attachment depthAttachment, Attachment stencilAttachment) :
+        HwRenderTarget(width, height), context(context), samples(samples) {
+    math::uint2 tmin = {std::numeric_limits<uint32_t>::max()};
+    UTILS_UNUSED_IN_RELEASE math::uint2 tmax = {0};
     UTILS_UNUSED_IN_RELEASE size_t attachmentCount = 0;
 
     for (size_t i = 0; i < MRT::MAX_SUPPORTED_RENDER_TARGET_COUNT; i++) {
-        MetalTexture* const texture = colorAttachments[i].texture;
-        const auto& level = colorAttachments[i].level;
-        const auto& layer = colorAttachments[i].layer;
-        if (!texture) {
+        if (!colorAttachments[i]) {
             continue;
         }
+        color[i] = colorAttachments[i];
 
-        FILAMENT_CHECK_PRECONDITION(texture->samples <= samples)
+        FILAMENT_CHECK_PRECONDITION(color[i].getSampleCount() <= samples)
                 << "MetalRenderTarget was initialized with a MSAA COLOR" << i
                 << " texture, but sample count is " << samples << ".";
 
-        const auto twidth = std::max(1u, texture->width >> level);
-        const auto theight = std::max(1u, texture->height >> level);
+        auto t = color[i].metalTexture;
+        const auto twidth = std::max(1u, t->width >> color[i].level);
+        const auto theight = std::max(1u, t->height >> color[i].level);
         tmin = { std::min(tmin.x, twidth), std::min(tmin.y, theight) };
         tmax = { std::max(tmax.x, twidth), std::max(tmax.y, theight) };
         attachmentCount++;
 
-        id<MTLTexture> mtlTexture = texture->getMtlTextureForWrite();
-        color[i] = MetalAttachment(mtlTexture, level, layer);
-
         // If we were given a single-sampled texture but the samples parameter is > 1, we create
         // a multisampled sidecar texture and do a resolve automatically.
-        if (samples > 1 && texture->samples == 1) {
-            auto& sidecar = texture->msaaSidecar;
+        if (samples > 1 && color[i].getSampleCount() == 1) {
+            auto& sidecar = color[i].metalTexture->msaaSidecar;
             if (!sidecar) {
-                sidecar = createMultisampledTexture(mtlTexture.pixelFormat, texture->width,
-                        texture->height, samples);
+                sidecar = createMultisampledTexture(color[i].getPixelFormat(),
+                        color[i].metalTexture->width, color[i].metalTexture->height, samples);
             }
-            color[i] = MetalAttachment(mtlTexture, level, layer).withMsaaTexture(sidecar);
         }
     }
 
-    if (depthAttachment.texture) {
-        MetalTexture* const texture = depthAttachment.texture;
-        const auto& level = depthAttachment.level;
-        const auto& layer = depthAttachment.layer;
+    if (depthAttachment) {
+        depth = depthAttachment;
 
-        FILAMENT_CHECK_PRECONDITION(texture->samples <= samples)
+        FILAMENT_CHECK_PRECONDITION(depth.getSampleCount() <= samples)
                 << "MetalRenderTarget was initialized with a MSAA DEPTH texture, but sample count "
                    "is "
                 << samples << ".";
 
-        const auto twidth = std::max(1u, texture->width >> level);
-        const auto theight = std::max(1u, texture->height >> level);
+        auto t = depth.metalTexture;
+        const auto twidth = std::max(1u, t->width >> depth.level);
+        const auto theight = std::max(1u, t->height >> depth.level);
         tmin = { math::min(tmin.x, twidth), math::min(tmin.y, theight) };
         tmax = { math::max(tmax.x, twidth), math::max(tmax.y, theight) };
         attachmentCount++;
 
-        id<MTLTexture> mtlTexture = texture->getMtlTextureForWrite();
-        depth = MetalAttachment(mtlTexture, level, layer);
-
         // If we were given a single-sampled texture but the samples parameter is > 1, we create
         // a multisampled sidecar texture and do a resolve automatically.
-        if (samples > 1 && texture->samples == 1) {
-            auto& sidecar = texture->msaaSidecar;
+        if (samples > 1 && depth.getSampleCount() == 1) {
+            auto& sidecar = depth.metalTexture->msaaSidecar;
             if (!sidecar) {
-                sidecar = createMultisampledTexture(mtlTexture.pixelFormat, texture->width,
-                        texture->height, samples);
+                sidecar = createMultisampledTexture(depth.getPixelFormat(),
+                        depth.metalTexture->width, depth.metalTexture->height, samples);
             }
-            depth = MetalAttachment(mtlTexture, level, layer).withMsaaTexture(sidecar);
         }
     }
 
-    if (stencilAttachment.texture) {
-        // stencil = stencilAttachment;
-        MetalTexture* const texture = stencilAttachment.texture;
-        const auto& level = stencilAttachment.level;
-        const auto& layer = stencilAttachment.layer;
+    if (stencilAttachment) {
+        stencil = stencilAttachment;
 
-        FILAMENT_CHECK_PRECONDITION(texture->samples <= samples)
+        FILAMENT_CHECK_PRECONDITION(stencil.getSampleCount() <= samples)
                 << "MetalRenderTarget was initialized with a MSAA STENCIL texture, but sample "
                    "count is "
                 << samples << ".";
 
-        const auto twidth = std::max(1u, texture->width >> level);
-        const auto theight = std::max(1u, texture->height >> level);
+        auto t = stencil.metalTexture;
+        const auto twidth = std::max(1u, t->width >> stencil.level);
+        const auto theight = std::max(1u, t->height >> stencil.level);
         tmin = { math::min(tmin.x, twidth), math::min(tmin.y, theight) };
         tmax = { math::max(tmax.x, twidth), math::max(tmax.y, theight) };
         attachmentCount++;
 
-        id<MTLTexture> mtlTexture = texture->getMtlTextureForWrite();
-        stencil = MetalAttachment(mtlTexture, level, layer);
-
         // If we were given a single-sampled texture but the samples parameter is > 1, we create
         // a multisampled sidecar texture and do a resolve automatically.
-        if (samples > 1 && texture->samples == 1) {
-            auto& sidecar = texture->msaaSidecar;
+        if (samples > 1 && stencil.getSampleCount() == 1) {
+            auto& sidecar = stencil.metalTexture->msaaSidecar;
             if (!sidecar) {
-                sidecar = createMultisampledTexture(mtlTexture.pixelFormat, texture->width,
-                        texture->height, samples);
+                sidecar = createMultisampledTexture(stencil.getPixelFormat(),
+                        stencil.metalTexture->width, stencil.metalTexture->height, samples);
             }
-            stencil = MetalAttachment(mtlTexture, level, layer).withMsaaTexture(sidecar);
         }
     }
 
@@ -1159,105 +1070,105 @@ void MetalRenderTarget::setUpRenderPassAttachments(MTLRenderPassDescriptor* desc
     const auto discardFlags = params.flags.discardEnd;
 
     for (size_t i = 0; i < MRT::MAX_SUPPORTED_RENDER_TARGET_COUNT; i++) {
-        MetalAttachment attachment = getDrawColorAttachment(i);
+        Attachment attachment = getDrawColorAttachment(i);
         if (!attachment) {
             continue;
         }
 
         descriptor.colorAttachments[i].texture = attachment.getTexture();
-        descriptor.colorAttachments[i].level = attachment.getLevel();
-        descriptor.colorAttachments[i].slice = attachment.getLayer();
+        descriptor.colorAttachments[i].level = attachment.level;
+        descriptor.colorAttachments[i].slice = attachment.layer;
         descriptor.colorAttachments[i].loadAction = getLoadAction(params, getTargetBufferFlagsAt(i));
         descriptor.colorAttachments[i].storeAction = getStoreAction(params,
                 getTargetBufferFlagsAt(i));
         descriptor.colorAttachments[i].clearColor = MTLClearColorMake(
                 params.clearColor.r, params.clearColor.g, params.clearColor.b, params.clearColor.a);
 
-        if (attachment.getMsaaTexture()) {
-            // Check that the loadAction is valid for MSAA targets: either DontCare or Clear.
+        const bool automaticResolve = samples > 1 && attachment.getSampleCount() == 1;
+        if (automaticResolve) {
             // We're rendering into our temporary MSAA texture and doing an automatic resolve.
             // We should not be attempting to load anything into the MSAA texture.
-            // This might happen if the user is rendering multiple views into a MSAA SwapChain,
-            // which is not supported. In that case, ignore the load action.
-            if (descriptor.colorAttachments[i].loadAction == MTLLoadActionLoad) {
-                descriptor.colorAttachments[i].loadAction = MTLLoadActionDontCare;
-            }
+            assert_invariant(descriptor.colorAttachments[i].loadAction != MTLLoadActionLoad);
+            assert_invariant(!defaultRenderTarget);
 
-            descriptor.colorAttachments[i].texture = attachment.getMsaaTexture();
+            id<MTLTexture> sidecar = attachment.getMSAASidecarTexture();
+            assert_invariant(sidecar);
+
+            descriptor.colorAttachments[i].texture = sidecar;
             descriptor.colorAttachments[i].level = 0;
             descriptor.colorAttachments[i].slice = 0;
             const bool discard = any(discardFlags & getTargetBufferFlagsAt(i));
             if (!discard) {
-                descriptor.colorAttachments[i].resolveTexture = attachment.getTexture();
-                descriptor.colorAttachments[i].resolveLevel = attachment.getLevel();
-                descriptor.colorAttachments[i].resolveSlice = attachment.getLayer();
+                descriptor.colorAttachments[i].resolveTexture = attachment.texture;
+                descriptor.colorAttachments[i].resolveLevel = attachment.level;
+                descriptor.colorAttachments[i].resolveSlice = attachment.layer;
                 descriptor.colorAttachments[i].storeAction = MTLStoreActionMultisampleResolve;
             }
         }
     }
 
-    MetalAttachment depthAttachment = getDepthAttachment();
+    Attachment depthAttachment = getDepthAttachment();
     if (depthAttachment) {
         descriptor.depthAttachment.texture = depthAttachment.getTexture();
-        descriptor.depthAttachment.level = depthAttachment.getLevel();
-        descriptor.depthAttachment.slice = depthAttachment.getLayer();
+        descriptor.depthAttachment.level = depthAttachment.level;
+        descriptor.depthAttachment.slice = depthAttachment.layer;
         descriptor.depthAttachment.loadAction = getLoadAction(params, TargetBufferFlags::DEPTH);
         descriptor.depthAttachment.storeAction = getStoreAction(params, TargetBufferFlags::DEPTH);
         descriptor.depthAttachment.clearDepth = params.clearDepth;
     }
 
-    if (depthAttachment.getMsaaTexture()) {
-        // Check that the loadAction is valid for MSAA targets: either DontCare or Clear.
+    const bool depthAutomaticResolve = samples > 1 && depthAttachment.getSampleCount() == 1;
+    if (depthAutomaticResolve) {
         // We're rendering into our temporary MSAA texture and doing an automatic resolve.
         // We should not be attempting to load anything into the MSAA texture.
-        // This might happen if the user is rendering multiple views into a MSAA SwapChain,
-        // which is not supported. In that case, ignore the load action.
-        if (descriptor.depthAttachment.loadAction == MTLLoadActionLoad) {
-            descriptor.depthAttachment.loadAction = MTLLoadActionDontCare;
-        }
+        assert_invariant(descriptor.depthAttachment.loadAction != MTLLoadActionLoad);
+        assert_invariant(!defaultRenderTarget);
 
-        descriptor.depthAttachment.texture = depthAttachment.getMsaaTexture();
+        id<MTLTexture> sidecar = depthAttachment.getMSAASidecarTexture();
+        assert_invariant(sidecar);
+
+        descriptor.depthAttachment.texture = sidecar;
         descriptor.depthAttachment.level = 0;
         descriptor.depthAttachment.slice = 0;
         const bool discard = any(discardFlags & TargetBufferFlags::DEPTH);
         if (!discard) {
             assert_invariant(context->supportsAutoDepthResolve);
             descriptor.depthAttachment.resolveTexture = depthAttachment.getTexture();
-            descriptor.depthAttachment.resolveLevel = depthAttachment.getLevel();
-            descriptor.depthAttachment.resolveSlice = depthAttachment.getLayer();
+            descriptor.depthAttachment.resolveLevel = depthAttachment.level;
+            descriptor.depthAttachment.resolveSlice = depthAttachment.layer;
             descriptor.depthAttachment.storeAction = MTLStoreActionMultisampleResolve;
         }
     }
 
-    MetalAttachment stencilAttachment = getStencilAttachment();
+    Attachment stencilAttachment = getStencilAttachment();
     if (stencilAttachment) {
         descriptor.stencilAttachment.texture = stencilAttachment.getTexture();
-        descriptor.stencilAttachment.level = stencilAttachment.getLevel();
-        descriptor.stencilAttachment.slice = stencilAttachment.getLayer();
+        descriptor.stencilAttachment.level = stencilAttachment.level;
+        descriptor.stencilAttachment.slice = stencilAttachment.layer;
         descriptor.stencilAttachment.loadAction = getLoadAction(params, TargetBufferFlags::STENCIL);
         descriptor.stencilAttachment.storeAction = getStoreAction(params, TargetBufferFlags::STENCIL);
         descriptor.stencilAttachment.clearStencil = params.clearStencil;
     }
 
-    if (stencilAttachment.getMsaaTexture()) {
-        // Check that the loadAction is valid for MSAA targets: either DontCare or Clear.
+    const bool stencilAutomaticResolve = samples > 1 && stencilAttachment.getSampleCount() == 1;
+    if (stencilAutomaticResolve) {
         // We're rendering into our temporary MSAA texture and doing an automatic resolve.
         // We should not be attempting to load anything into the MSAA texture.
-        // This might happen if the user is rendering multiple views into a MSAA SwapChain,
-        // which is not supported. In that case, ignore the load action.
-        if (descriptor.stencilAttachment.loadAction == MTLLoadActionLoad) {
-            descriptor.stencilAttachment.loadAction = MTLLoadActionDontCare;
-        }
+        assert_invariant(descriptor.stencilAttachment.loadAction != MTLLoadActionLoad);
+        assert_invariant(!defaultRenderTarget);
 
-        descriptor.stencilAttachment.texture = stencilAttachment.getMsaaTexture();
+        id<MTLTexture> sidecar = stencilAttachment.getMSAASidecarTexture();
+        assert_invariant(sidecar);
+
+        descriptor.stencilAttachment.texture = sidecar;
         descriptor.stencilAttachment.level = 0;
         descriptor.stencilAttachment.slice = 0;
         const bool discard = any(discardFlags & TargetBufferFlags::STENCIL);
         if (!discard) {
             assert_invariant(context->supportsAutoDepthResolve);
             descriptor.stencilAttachment.resolveTexture = stencilAttachment.getTexture();
-            descriptor.stencilAttachment.resolveLevel = stencilAttachment.getLevel();
-            descriptor.stencilAttachment.resolveSlice = stencilAttachment.getLayer();
+            descriptor.stencilAttachment.resolveLevel = stencilAttachment.level;
+            descriptor.stencilAttachment.resolveSlice = stencilAttachment.layer;
             descriptor.stencilAttachment.storeAction = MTLStoreActionMultisampleResolve;
             if (@available(iOS 12.0, *)) {
                 descriptor.stencilAttachment.stencilResolveFilter = MTLMultisampleStencilResolveFilterSample0;
@@ -1272,46 +1183,44 @@ bool MetalRenderTarget::involvesAbandonedSwapChain() const noexcept {
     return (draw && draw->isAbandoned()) || (read && read->isAbandoned());
 }
 
-MetalAttachment MetalRenderTarget::getDrawColorAttachment(size_t index) {
+MetalRenderTarget::Attachment MetalRenderTarget::getDrawColorAttachment(size_t index) {
     assert_invariant(index < MRT::MAX_SUPPORTED_RENDER_TARGET_COUNT);
+    Attachment result = color[index];
     if (index == 0 && defaultRenderTarget) {
         assert_invariant(context->currentDrawSwapChain);
-        return context->currentDrawSwapChain->acquireDrawable();
+        result.texture = context->currentDrawSwapChain->acquireDrawable();
+        // acquireDrawable may fail to acquire the drawable, in which case result.texture will be
+        // nil, and an invalid attachment
     }
-    return color[index];
+    return result;
 }
 
-MetalAttachment MetalRenderTarget::getReadColorAttachment(size_t index) {
+MetalRenderTarget::Attachment MetalRenderTarget::getReadColorAttachment(size_t index) {
     assert_invariant(index < MRT::MAX_SUPPORTED_RENDER_TARGET_COUNT);
+    Attachment result = color[index];
     if (index == 0 && defaultRenderTarget) {
         assert_invariant(context->currentReadSwapChain);
-        return context->currentReadSwapChain->acquireDrawable();
+        result.texture = context->currentReadSwapChain->acquireDrawable();
+        // acquireDrawable may fail to acquire the drawable, in which case result.texture will be
+        // nil, and an invalid attachment
     }
-    return color[index];
+    return result;
 }
 
-MetalAttachment MetalRenderTarget::getDepthAttachment() {
+MetalRenderTarget::Attachment MetalRenderTarget::getDepthAttachment() {
+    Attachment result = depth;
     if (defaultRenderTarget) {
-        assert_invariant(context->currentDrawSwapChain);
-        return context->currentDrawSwapChain->acquireDepthTexture();
+        result.texture = context->currentDrawSwapChain->acquireDepthTexture();
     }
-    return depth;
+    return result;
 }
 
-MetalAttachment MetalRenderTarget::getStencilAttachment() {
+MetalRenderTarget::Attachment MetalRenderTarget::getStencilAttachment() {
+    Attachment result = stencil;
     if (defaultRenderTarget) {
-        assert_invariant(context->currentDrawSwapChain);
-        return context->currentDrawSwapChain->acquireStencilTexture();
+        result.texture = context->currentDrawSwapChain->acquireStencilTexture();
     }
-    return stencil;
-}
-
-NSUInteger MetalRenderTarget::getSampleCount() const {
-    if (defaultRenderTarget) {
-        assert_invariant(context->currentDrawSwapChain);
-        return context->currentDrawSwapChain->getSampleCount();
-    }
-    return samples;
+    return result;
 }
 
 MTLLoadAction MetalRenderTarget::getLoadAction(const RenderPassParams& params,
@@ -1395,30 +1304,20 @@ void MetalFence::onSignal(MetalFenceSignalBlock block) {
 FenceStatus MetalFence::wait(uint64_t timeoutNs) {
     if (@available(iOS 12, *)) {
         using ns = std::chrono::nanoseconds;
-
-        // keep a reference on the stack so our state cannot be destroyed while we wait
-        auto state = this->state;
-
         std::unique_lock<std::mutex> guard(state->mutex);
         while (state->status == FenceStatus::TIMEOUT_EXPIRED) {
             if (timeoutNs == FENCE_WAIT_FOR_EVER) {
                 state->cv.wait(guard);
             } else if (timeoutNs == 0 ||
                     state->cv.wait_for(guard, ns(timeoutNs)) == std::cv_status::timeout) {
-                return state->status;
+                return FenceStatus::TIMEOUT_EXPIRED;
             }
         }
-        return state->status;
+        return FenceStatus::CONDITION_SATISFIED;
     }
     return FenceStatus::ERROR;
 }
 
-void MetalFence::cancel() {
-    std::unique_lock guard(state->mutex);
-    state->status = FenceStatus::ERROR;
-    state->cv.notify_all();
-}
-
 MetalDescriptorSetLayout::MetalDescriptorSetLayout(DescriptorSetLayout&& l) noexcept
     : mLayout(std::move(l)) {
     size_t dynamicBindings = 0;
@@ -1587,11 +1486,6 @@ id<MTLBuffer> MetalDescriptorSet::finalizeAndGetBuffer(MetalDriver* driver, Shad
         buffer = { [context.device newBufferWithLength:encoder.encodedLength
                                                options:MTLResourceStorageModeShared],
             TrackedMetalBuffer::Type::DESCRIPTOR_SET };
-#if FILAMENT_METAL_DEBUG_LABELS
-        if (!label.empty()) {
-            buffer.get().label = @(label.c_str_safe());
-        }
-#endif
     }
     [encoder setArgumentBuffer:buffer.get() offset:0];