Merge branch 'rc/1.21.3' into release

The progress bar in `gltf_viewer` should not appear to hang if any
of an asset's textures fail to load.

.github/workflows/release.yml

@@ -50,8 +50,7 @@ jobs:
           cd build/$WORKFLOW_OS && printf "y" | ./build.sh release
       - name: Upload release assets
         run: |
-          pip3 install setuptools
-          pip3 install PyGithub
+          xargs -L 1 sudo pip3 install < build/common/requirements.txt
           if [ -f out/filament-release-darwin.tgz ]; then mv out/filament-release-darwin.tgz out/filament-${TAG}-mac.tgz; fi;
           if [ -f out/filament-release-linux.tgz ]; then mv out/filament-release-linux.tgz out/filament-${TAG}-linux.tgz; fi;
           python3 build/common/upload-assets.py ${TAG} out/*.tgz
@@ -80,8 +79,7 @@ jobs:
           cd build/web && printf "y" | ./build.sh release
       - name: Upload release assets
         run: |
-          pip3 install setuptools
-          pip3 install PyGithub
+          xargs -L 1 sudo pip3 install < build/common/requirements.txt
           mv out/filament-release-web.tgz out/filament-${TAG}-web.tgz
           python3 build/common/upload-assets.py ${TAG} out/*.tgz
         env:
@@ -123,8 +121,7 @@ jobs:
           APK_KEYSTORE_PASS: ${{ secrets.APK_KEYSTORE_PASS }}
       - name: Upload release assets
         run: |
-          pip3 install setuptools
-          pip3 install PyGithub
+          xargs -L 1 sudo pip3 install < build/common/requirements.txt
           mv out/filament-android-release.aar out/filament-${TAG}-android.aar
           mv out/filamat-android-release.aar out/filamat-${TAG}-android.aar
           mv out/filamat-android-lite-release.aar out/filamat-${TAG}-lite-android.aar
@@ -157,8 +154,7 @@ jobs:
           cd build/ios && printf "y" | ./build.sh release
       - name: Upload release assets
         run: |
-          pip3 install setuptools
-          pip3 install PyGithub
+          xargs -L 1 sudo pip3 install < build/common/requirements.txt
           mv out/filament-release-ios.tgz out/filament-${TAG}-ios.tgz
           python3 build/common/upload-assets.py ${TAG} out/*.tgz
         env:

CMakeLists.txt

@@ -647,12 +647,14 @@ add_subdirectory(${LIBRARIES}/gltfio)
 add_subdirectory(${LIBRARIES}/ibl)
 add_subdirectory(${LIBRARIES}/iblprefilter)
 add_subdirectory(${LIBRARIES}/image)
+add_subdirectory(${LIBRARIES}/ktxreader)
 add_subdirectory(${LIBRARIES}/math)
 add_subdirectory(${LIBRARIES}/mathio)
 add_subdirectory(${LIBRARIES}/utils)
 add_subdirectory(${LIBRARIES}/viewer)
 add_subdirectory(${FILAMENT}/filament)
 add_subdirectory(${FILAMENT}/shaders)
+add_subdirectory(${EXTERNAL}/basisu/tnt)
 add_subdirectory(${EXTERNAL}/civetweb/tnt)
 add_subdirectory(${EXTERNAL}/hat-trie/tnt)
 add_subdirectory(${EXTERNAL}/imgui/tnt)
@@ -705,8 +707,6 @@ if (IS_HOST_PLATFORM)
 
     add_subdirectory(${FILAMENT}/samples)
 
-    add_subdirectory(${EXTERNAL}/astcenc/tnt)
-    add_subdirectory(${EXTERNAL}/etc2comp)
     add_subdirectory(${EXTERNAL}/libassimp/tnt)
     add_subdirectory(${EXTERNAL}/libpng/tnt)
     add_subdirectory(${EXTERNAL}/libsdl2/tnt)

README.md

@@ -31,7 +31,7 @@ repositories {
 }
 
 dependencies {
-    implementation 'com.google.android.filament:filament-android:1.21.0'
+    implementation 'com.google.android.filament:filament-android:1.21.3'
 }
 ```
 
@@ -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:
 
 ```
-pod 'Filament', '~> 1.21.0'
+pod 'Filament', '~> 1.21.3'
 ```
 
 ### Snapshots

RELEASE_NOTES.md

@@ -3,9 +3,33 @@
 This file contains one line summaries of commits that are worthy of mentioning in release notes.
 A new header is inserted each time a *tag* is created.
 
-## v1.21.1 (currently main branch)
+## v1.21.3 (currently main branch)
 
-- engine: allow both screen-space refraction and screen-space reflections on the same object [⚠️ **Material breakage**].
+- Java: Renamed the `KTXLoader` Kotlin class to `KTX1Loader`.  [⚠️ **API Change**].
+- libs: Added `Ktx2Reader` and `BasisEncoder` to support Basis-encoded KTX2 files.
+- engine: Remove deprecated `Stream` APIs, see `Texture::import()` for an alternative [⚠️ **API Change**].
+- tools: Removed KTX1 compression support from mipgen.  [⚠️ **API Change**].
+- tools: Added support for KTX2 to mipgen.
+- gltfio: Added `resetBoneMatrices()` method.
+- gltfio: Introduced `TextureProvider` interface.  [⚠️ **API Change**].
+- gltfio: Fix progress indicator when error occurs.
+- samples: Desktop and Web Suzanne samples now use KTX2 instead of KTX1.
+- samples: Fix regression with sample-gltf-viewer and zip files.
+
+## v1.21.2
+
+- Java: Add Java binding to get skins in `FilamentAsset`.
+- libs: Add libs/ktxreader [⚠️ **API Change**].
+- mipgen: fixups / clarification regarding sRGB.
+- WebGL: fix intermittent 'detached ArrayBuffer' errors.
+
+## v1.21.1
+
+- engine: Allow both screen-space refraction and screen-space reflections on the same object [⚠️ **Material breakage**].
+- engine: Optimizations for screen-space reflections.
+- engine: Remove `Viewport::scale()` [⚠️ **API Change**].
+- engine: Fix 12x overallocation of memory in `MorphTargetBuffer`.
+- Metal: Fix validation error when reading from default `SwapChain`.
 
 ## v1.21.0
 
@@ -440,7 +464,7 @@ devices.
 - engine: Fix RenderTarget NPE when depth is not present.
 - engine: Improvements to Camera APIs. Move focus distance from DofOptions to Camera.
 - engine: VSM shadows now support `shadowMultiplier`.
-- java: Expose severla MaterialInstance APIs (setColorWrite, setDepthWrite, setDepthCulling) that
+- java: Expose several MaterialInstance APIs (setColorWrite, setDepthWrite, setDepthCulling) that
   should have been public.
 - java: fix bug with Texture::setImage buffer size calculation.
 

android/build.gradle

@@ -11,6 +11,9 @@
 // com.google.android.filament.exclude-vulkan
 //     When set, support for Vulkan will be excluded.
 //
+// com.google.android.filament.matdbg
+//     When set, enables matdbg, disables shader optimizations
+//
 // com.google.android.filament.skip-samples
 //     Exclude samples from the project. Useful to speed up compilation.
 //
@@ -59,6 +62,11 @@ buildscript {
             .forUseAtConfigurationTime()
             .isPresent()
 
+    def matdbg = providers
+            .gradleProperty("com.google.android.filament.matdbg")
+            .forUseAtConfigurationTime()
+            .isPresent()
+
     def abis = ["arm64-v8a", "armeabi-v7a", "x86_64", "x86"]
     def newAbis = providers
             .gradleProperty("com.google.android.filament.abis")
@@ -102,7 +110,9 @@ buildscript {
         "-DANDROID_PLATFORM=21",
         "-DANDROID_STL=c++_static",
         "-DFILAMENT_DIST_DIR=${filamentPath}".toString(),
-        "-DFILAMENT_SUPPORTS_VULKAN=${excludeVulkan ? 'OFF' : 'ON'}".toString()
+        "-DFILAMENT_SUPPORTS_VULKAN=${excludeVulkan ? 'OFF' : 'ON'}".toString(),
+        "-DFILAMENT_ENABLE_MATDBG=${matdbg ? 'ON' : 'OFF'}".toString(),
+        "-DFILAMENT_DISABLE_MATOPT=${matdbg ? 'ON' : 'OFF'}".toString()
     ]
 
     ext.cppFlags = [

android/filamat-android/src/main/java/com/google/android/filament/filamat/MaterialBuilder.java

@@ -133,7 +133,7 @@ public class MaterialBuilder {
         FADE,                   // material is transparent and color is alpha-pre-multiplied,
                                 // affects specular lighting
         MULTIPLY,               // material darkens what's behind it
-        SCREN                   // material brightens what's behind it
+        SCREEN                  // material brightens what's behind it
     }
 
     public enum VertexDomain {

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

@@ -98,16 +98,6 @@ Java_com_google_android_filament_Stream_nBuilderStreamSource(JNIEnv* env,
     builder->setStreamSource(env, streamSource);
 }
 
-extern "C" JNIEXPORT void JNICALL
-Java_com_google_android_filament_Stream_nBuilderStream(JNIEnv*, jclass,
-        jlong nativeStreamBuilder, jlong externalTextureId) {
-    StreamBuilder* builder = (StreamBuilder*) nativeStreamBuilder;
-#pragma clang diagnostic push
-#pragma clang diagnostic ignored "-Wdeprecated-declarations"
-    builder->builder()->stream(externalTextureId);
-#pragma clang diagnostic pop
-}
-
 extern "C" JNIEXPORT void JNICALL
 Java_com_google_android_filament_Stream_nBuilderWidth(JNIEnv*, jclass,
         jlong nativeStreamBuilder, jint width) {
@@ -143,41 +133,6 @@ Java_com_google_android_filament_Stream_nSetDimensions(JNIEnv*, jclass, jlong na
     stream->setDimensions((uint32_t) width, (uint32_t) height);
 }
 
-extern "C" JNIEXPORT jint JNICALL
-Java_com_google_android_filament_Stream_nReadPixels(JNIEnv *env, jclass,
-        jlong nativeStream, jlong nativeEngine,
-        jint xoffset, jint yoffset, jint width, jint height,
-        jobject storage, jint remaining,
-        jint left, jint top, jint type, jint alignment, jint stride, jint format,
-        jobject handler, jobject runnable) {
-    Stream *stream = (Stream *) nativeStream;
-    Engine *engine = (Engine *) nativeEngine;
-
-    stride = stride ? stride : width;
-    size_t sizeInBytes = PixelBufferDescriptor::computeDataSize(
-            (PixelDataFormat) format, (PixelDataType) type,
-            (size_t) stride, (size_t) (height + top), (size_t) alignment);
-
-    AutoBuffer nioBuffer(env, storage, 0);
-    if (sizeInBytes > (remaining << nioBuffer.getShift())) {
-        // BufferOverflowException
-        return -1;
-    }
-
-    void *buffer = nioBuffer.getData();
-    auto *callback = JniBufferCallback::make(engine, env, handler, runnable, std::move(nioBuffer));
-
-    PixelBufferDescriptor desc(buffer, sizeInBytes, (backend::PixelDataFormat) format,
-            (backend::PixelDataType) type, (uint8_t) alignment, (uint32_t) left, (uint32_t) top,
-            (uint32_t) stride,
-            callback->getHandler(), &JniBufferCallback::postToJavaAndDestroy, callback);
-
-    stream->readPixels(uint32_t(xoffset), uint32_t(yoffset), uint32_t(width), uint32_t(height),
-            std::move(desc));
-
-    return 0;
-}
-
 extern "C" JNIEXPORT jlong JNICALL
 Java_com_google_android_filament_Stream_nGetTimestamp(JNIEnv*, jclass, jlong nativeStream) {
     Stream *stream = (Stream *) nativeStream;

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

@@ -531,6 +531,10 @@ public class Renderer {
      * Typically, this will happen after multiple calls to {@link #beginFrame},
      * {@link #render}, {@link #endFrame}.</p>
      * <br>
+     * <p>OpenGL only: if issuing a <code>readPixels</code> on a {@link RenderTarget} backed by a
+     * {@link Texture} that had data uploaded to it via {@link Texture#setImage}, the data returned
+     * from <code>readPixels</code> will be y-flipped with respect to the {@link Texture#setImage}
+     * call.</p>
      * <p><code>readPixels</code> is intended for debugging and testing.
      * It will impact performance significantly.</p>
      *

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

@@ -103,9 +103,6 @@ public class Stream {
         /** Not synchronized but copy-free. Good for video. */
         NATIVE,
 
-        /** Synchronized, but GL-only and incurs copies. Good for AR on devices before API 26. */
-        TEXTURE_ID,
-
         /** Synchronized, copy-free, and take a release callback. Good for AR but requires API 26+. */
         ACQUIRED,
     };
@@ -121,7 +118,7 @@ public class Stream {
      * By default, Stream objects are {@link StreamType#ACQUIRED ACQUIRED} and must have external images pushed to them via
      * {@link #setAcquiredImage}.
      *
-     * To create a {@link StreamType#NATIVE NATIVE} or {@link StreamType#TEXTURE_ID TEXTURE_ID} stream, call one of the <pre>stream</pre> methods
+     * To create a {@link StreamType#NATIVE NATIVE} stream, call one of the <pre>stream</pre> methods
      * on the builder.
      */
     public static class Builder {
@@ -156,27 +153,6 @@ public class Stream {
             throw new IllegalArgumentException("Invalid stream source: " + streamSource);
         }
 
-        /**
-         * Creates a {@link StreamType#TEXTURE_ID TEXTURE_ID} stream. A copy stream will sample data from the supplied
-         * external texture and copy it into an internal private texture.
-         *
-         * <p>Currently only OpenGL external texture ids are supported.</p>
-         *
-         * @param externalTextureId An opaque texture id (typically a GLuint created with
-         *                          <code>glGenTextures()</code>) in a context shared with
-         *                          filament -- in that case this texture's target must be
-         *                          <code>GL_TEXTURE_EXTERNAL_OES.</code>
-         * @return This Builder, for chaining calls.
-         * @see Texture#setExternalStream
-         * @deprecated this method existed only for ARCore which doesn't need this anymore, use {@link Texture.Builder#importTexture(long)} instead.
-         */
-        @Deprecated
-        @NonNull
-        public Builder stream(long externalTextureId) {
-            nBuilderStream(mNativeBuilder, externalTextureId);
-            return this;
-        }
-
         /**
          * @param width initial width of the incoming stream. Whether this value is used is
          *              stream dependent. On Android, it must be set when using
@@ -276,92 +252,6 @@ public class Stream {
         nSetDimensions(getNativeObject(), width, height);
     }
 
-    /**
-     * Reads back the content of the last frame of a <code>Stream</code> since the last call to
-     * {@link Renderer#beginFrame}.
-     *
-     * <p>The Stream must be a copy stream, which can be checked with {@link #getStreamType()}.
-     * This function is a no-op otherwise.</p>
-     *
-     * <pre>
-     *
-     *  Stream buffer                  User buffer (PixelBufferDescriptor)
-     *  +--------------------+
-     *  |                    |                .stride         .alignment
-     *  |                    |         ----------------------->-->
-     *  |                    |         O----------------------+--+   low addresses
-     *  |                    |         |          |           |  |
-     *  |             w      |         |          | .top      |  |
-     *  |       <--------->  |         |          V           |  |
-     *  |       +---------+  |         |     +---------+      |  |
-     *  |       |     ^   |  | ======> |     |         |      |  |
-     *  |   x   |    h|   |  |         |.left|         |      |  |
-     *  +------>|     v   |  |         +---->|         |      |  |
-     *  |       +.........+  |         |     +.........+      |  |
-     *  |            ^       |         |                      |  |
-     *  |          y |       |         +----------------------+--+  high addresses
-     *  O------------+-------+
-     *
-     * </pre>
-     *
-     * <p>Typically readPixels() will be called after {@link Renderer#beginFrame}.</p>
-     *
-     * <p>After calling this method, the callback associated with <code>buffer</code>
-     * will be invoked on the main thread, indicating that the read-back has completed.
-     * Typically, this will happen after multiple calls to {@link Renderer#beginFrame},
-     * {@link Renderer#render}, {@link Renderer#endFrame}.</p>
-     *
-     * <p><code>readPixels</code> is intended for debugging and testing.
-     * It will impact performance significantly.</p>
-     *
-     * @param xoffset   left offset of the sub-region to read back
-     * @param yoffset   bottom offset of the sub-region to read back
-     * @param width     width of the sub-region to read back
-     * @param height    height of the sub-region to read back
-     * @param buffer    client-side buffer where the read-back will be written
-     *
-     *                  <p>
-     *                  The following format are always supported:
-     *                      <li>{@link Texture.Format#RGBA}</li>
-     *                      <li>{@link Texture.Format#RGBA_INTEGER}</li>
-     *                  </p>
-     *
-     *                  <p>
-     *                  The following types are always supported:
-     *                      <li>{@link Texture.Type#UBYTE}</li>
-     *                      <li>{@link Texture.Type#UINT}</li>
-     *                      <li>{@link Texture.Type#INT}</li>
-     *                      <li>{@link Texture.Type#FLOAT}</li>
-     *                  </p>
-     *
-     *                  <p>Other combination of format/type may be supported. If a combination is
-     *                  not supported, this operation may fail silently. Use a DEBUG build
-     *                  to get some logs about the failure.</p>
-     *
-     * @exception BufferOverflowException if the specified parameters would result in reading
-     * outside of <code>buffer</code>.
-     */
-    public void readPixels(
-            @IntRange(from = 0) int xoffset, @IntRange(from = 0) int yoffset,
-            @IntRange(from = 0) int width, @IntRange(from = 0) int height,
-            @NonNull Texture.PixelBufferDescriptor buffer) {
-
-        if (buffer.storage.isReadOnly()) {
-            throw new ReadOnlyBufferException();
-        }
-
-        int result = nReadPixels(getNativeObject(), mNativeEngine,
-                xoffset, yoffset, width, height,
-                buffer.storage, buffer.storage.remaining(),
-                buffer.left, buffer.top, buffer.type.ordinal(), buffer.alignment,
-                buffer.stride, buffer.format.ordinal(),
-                buffer.handler, buffer.callback);
-
-        if (result < 0) {
-            throw new BufferOverflowException();
-        }
-    }
-
     /**
      * Returns the presentation time of the currently displayed frame in nanosecond.
      *
@@ -387,7 +277,6 @@ public class Stream {
     private static native long nCreateBuilder();
     private static native void nDestroyBuilder(long nativeStreamBuilder);
     private static native void nBuilderStreamSource(long nativeStreamBuilder, Object streamSource);
-    private static native void nBuilderStream(long nativeStreamBuilder, long externalTextureId);
     private static native void nBuilderWidth(long nativeStreamBuilder, int width);
     private static native void nBuilderHeight(long nativeStreamBuilder, int height);
     private static native long nBuilderBuild(long nativeStreamBuilder, long nativeEngine);

android/filament-utils-android/CMakeLists.txt

@@ -14,6 +14,10 @@ add_library(image STATIC IMPORTED)
 set_target_properties(image PROPERTIES IMPORTED_LOCATION
         ${FILAMENT_DIR}/lib/${ANDROID_ABI}/libimage.a)
 
+add_library(ktxreader STATIC IMPORTED)
+set_target_properties(ktxreader PROPERTIES IMPORTED_LOCATION
+        ${FILAMENT_DIR}/lib/${ANDROID_ABI}/libktxreader.a)
+
 add_library(viewer STATIC IMPORTED)
 set_target_properties(viewer PROPERTIES IMPORTED_LOCATION
         ${FILAMENT_DIR}/lib/${ANDROID_ABI}/libviewer.a)
@@ -64,5 +68,6 @@ target_link_libraries(filament-utils-jni
         camutils
         iblprefilter
         image
+        ktxreader
         viewer
 )

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

@@ -20,13 +20,14 @@
 #include <filament/IndirectLight.h>
 #include <filament/Skybox.h>
 
-#include <image/KtxUtility.h>
+#include <ktxreader/Ktx1Reader.h>
 
 #include "common/NioUtils.h"
 
 using namespace filament;
 using namespace filament::math;
 using namespace image;
+using namespace ktxreader;
 
 jlong nCreateHDRTexture(JNIEnv* env, jclass,
         jlong nativeEngine, jobject javaBuffer, jint remaining, jint internalFormat);
@@ -35,9 +36,9 @@ static jlong nCreateKTXTexture(JNIEnv* env, jclass,
         jlong nativeEngine, jobject javaBuffer, jint remaining, jboolean srgb) {
     Engine* engine = (Engine*) nativeEngine;
     AutoBuffer buffer(env, javaBuffer, remaining);
-    KtxBundle* bundle = new KtxBundle((const uint8_t*) buffer.getData(), buffer.getSize());
-    return (jlong) ktx::createTexture(engine, *bundle, srgb, [](void* userdata) {
-        KtxBundle* bundle = (KtxBundle*) userdata;
+    Ktx1Bundle* bundle = new Ktx1Bundle((const uint8_t*) buffer.getData(), buffer.getSize());
+    return (jlong) Ktx1Reader::createTexture(engine, *bundle, srgb, [](void* userdata) {
+        Ktx1Bundle* bundle = (Ktx1Bundle*) userdata;
         delete bundle;
     }, bundle);
 }
@@ -46,9 +47,9 @@ static jlong nCreateIndirectLight(JNIEnv* env, jclass,
         jlong nativeEngine, jobject javaBuffer, jint remaining, jboolean srgb) {
     Engine* engine = (Engine*) nativeEngine;
     AutoBuffer buffer(env, javaBuffer, remaining);
-    KtxBundle* bundle = new KtxBundle((const uint8_t*) buffer.getData(), buffer.getSize());
-    Texture* cubemap = ktx::createTexture(engine, *bundle, srgb,  [](void* userdata) {
-        KtxBundle* bundle = (KtxBundle*) userdata;
+    Ktx1Bundle* bundle = new Ktx1Bundle((const uint8_t*) buffer.getData(), buffer.getSize());
+    Texture* cubemap = Ktx1Reader::createTexture(engine, *bundle, srgb,  [](void* userdata) {
+        Ktx1Bundle* bundle = (Ktx1Bundle*) userdata;
         delete bundle;
     }, bundle);
 
@@ -68,9 +69,9 @@ static jlong nCreateSkybox(JNIEnv* env, jclass,
         jlong nativeEngine, jobject javaBuffer, jint remaining, jboolean srgb) {
     Engine* engine = (Engine*) nativeEngine;
     AutoBuffer buffer(env, javaBuffer, remaining);
-    KtxBundle* bundle = new KtxBundle((const uint8_t*) buffer.getData(), buffer.getSize());
-    Texture* cubemap = ktx::createTexture(engine, *bundle, srgb,  [](void* userdata) {
-        KtxBundle* bundle = (KtxBundle*) userdata;
+    Ktx1Bundle* bundle = new Ktx1Bundle((const uint8_t*) buffer.getData(), buffer.getSize());
+    Texture* cubemap = Ktx1Reader::createTexture(engine, *bundle, srgb,  [](void* userdata) {
+        Ktx1Bundle* bundle = (Ktx1Bundle*) userdata;
         delete bundle;
     }, bundle);
     return (jlong) Skybox::Builder().environment(cubemap).showSun(true).build(*engine);
@@ -79,7 +80,7 @@ static jlong nCreateSkybox(JNIEnv* env, jclass,
 static jboolean nGetSphericalHarmonics(JNIEnv* env, jclass, jobject javaBuffer, jint remaining,
         jfloatArray outSphericalHarmonics_) {
     AutoBuffer buffer(env, javaBuffer, remaining);
-    KtxBundle bundle((const uint8_t*) buffer.getData(), buffer.getSize());
+    Ktx1Bundle bundle((const uint8_t*) buffer.getData(), buffer.getSize());
 
     jfloat* outSphericalHarmonics = env->GetFloatArrayElements(outSphericalHarmonics_, nullptr);
     const auto success = bundle.getSphericalHarmonics(
@@ -98,8 +99,8 @@ JNIEXPORT jint JNI_OnLoad(JavaVM* vm, void*) {
 
     int rc;
 
-    // KTXLoader
-    jclass ktxloaderClass = env->FindClass("com/google/android/filament/utils/KTXLoader");
+    // KTX1Loader
+    jclass ktxloaderClass = env->FindClass("com/google/android/filament/utils/KTX1Loader");
     if (ktxloaderClass == nullptr) return JNI_ERR;
     static const JNINativeMethod ktxMethods[] = {
         {(char*)"nCreateKTXTexture", (char*)"(JLjava/nio/Buffer;IZ)J", reinterpret_cast<void*>(nCreateKTXTexture)},

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

@@ -40,7 +40,7 @@ import com.google.android.filament.Renderer;
  *
  * When executing a test, clients should call tick() after each frame is rendered, which provides an
  * opportunity to push settings to Filament, increment the current test index (if enough time has
- * elapsed), and request an asychronous screenshot.
+ * elapsed), and request an asynchronous screenshot.
  *
  * The time to sleep between tests is configurable and can be set to zero. Automation also waits a
  * specified minimum number of frames between tests.

android/filament-utils-android/src/main/java/com/google/android/filament/utils/KTX1Loader.kt

@@ -24,12 +24,12 @@ import com.google.android.filament.Texture
 import java.nio.Buffer
 
 /**
- * Utilities for consuming KTX files and producing Filament textures, IBLs, and sky boxes.
+ * Utilities for consuming KTX1 files and producing Filament textures, IBLs, and sky boxes.
  *
  * KTX is a simple container format that makes it easy to bundle miplevels and cubemap faces
  * into a single file.
  */
-object KTXLoader {
+object KTX1Loader {
     class Options {
         var srgb = false
     }

android/gltfio-android/CMakeLists.txt

@@ -11,6 +11,10 @@ add_library(dracodec STATIC IMPORTED)
 set_target_properties(dracodec PROPERTIES IMPORTED_LOCATION
         ${FILAMENT_DIR}/lib/${ANDROID_ABI}/libdracodec.a)
 
+add_library(stb STATIC IMPORTED)
+set_target_properties(stb PROPERTIES IMPORTED_LOCATION
+        ${FILAMENT_DIR}/lib/${ANDROID_ABI}/libstb.a)
+
 add_library(utils STATIC IMPORTED)
 set_target_properties(utils PROPERTIES IMPORTED_LOCATION
         ${FILAMENT_DIR}/lib/${ANDROID_ABI}/libutils.a)
@@ -32,6 +36,7 @@ set(GLTFIO_SRCS
         ${GLTFIO_DIR}/include/gltfio/ResourceLoader.h
         ${GLTFIO_DIR}/include/gltfio/FilamentAsset.h
         ${GLTFIO_DIR}/include/gltfio/FilamentInstance.h
+        ${GLTFIO_DIR}/include/gltfio/TextureProvider.h
         ${GLTFIO_DIR}/include/gltfio/math.h
 
         ${GLTFIO_DIR}/src/Animator.cpp
@@ -47,13 +52,13 @@ set(GLTFIO_SRCS
         ${GLTFIO_DIR}/src/GltfEnums.h
         ${GLTFIO_DIR}/src/MaterialProvider.cpp
         ${GLTFIO_DIR}/src/ResourceLoader.cpp
+        ${GLTFIO_DIR}/src/StbProvider.cpp
         ${GLTFIO_DIR}/src/TangentsJob.h
         ${GLTFIO_DIR}/src/TangentsJob.cpp
         ${GLTFIO_DIR}/src/UbershaderLoader.cpp
         ${GLTFIO_DIR}/src/Wireframe.cpp
         ${GLTFIO_DIR}/src/Wireframe.h
         ${GLTFIO_DIR}/src/upcast.h
-        ${GLTFIO_DIR}/src/Image.cpp
 
         src/main/cpp/Animator.cpp
         src/main/cpp/AssetLoader.cpp
@@ -90,9 +95,9 @@ set_target_properties(gltfio-jni PROPERTIES LINK_DEPENDS ${CMAKE_CURRENT_SOURCE_
 
 if(GLTFIO_LITE)
         target_compile_definitions(gltfio-jni PUBLIC GLTFIO_LITE=1)
-        target_link_libraries(gltfio-jni filament-jni utils log gltfio_resources_lite)
+        target_link_libraries(gltfio-jni filament-jni utils log stb gltfio_resources_lite)
 else()
-        target_link_libraries(gltfio-jni filament-jni utils log gltfio_resources)
+        target_link_libraries(gltfio-jni filament-jni utils log stb gltfio_resources)
 
         # Enable Draco in the non-lite variant of gltfio.
         target_link_libraries(gltfio-jni dracodec)

android/gltfio-android/src/main/cpp/Animator.cpp

@@ -36,6 +36,12 @@ Java_com_google_android_filament_gltfio_Animator_nUpdateBoneMatrices(JNIEnv*, jc
     animator->updateBoneMatrices();
 }
 
+extern "C" JNIEXPORT void JNICALL
+Java_com_google_android_filament_gltfio_Animator_nResetBoneMatrices(JNIEnv*, jclass, jlong nativeAnimator) {
+    Animator* animator = (Animator*) nativeAnimator;
+    animator->resetBoneMatrices();
+}
+
 extern "C" JNIEXPORT jint JNICALL
 Java_com_google_android_filament_gltfio_Animator_nGetAnimationCount(JNIEnv*, jclass, jlong nativeAnimator) {
     Animator* animator = (Animator*) nativeAnimator;

android/gltfio-android/src/main/cpp/FilamentAsset.cpp

@@ -201,6 +201,44 @@ Java_com_google_android_filament_gltfio_FilamentAsset_nGetExtras(JNIEnv* env, jc
     return val ? env->NewStringUTF(val) : nullptr;
 }
 
+extern "C" JNIEXPORT jint JNICALL
+Java_com_google_android_filament_gltfio_FilamentAsset_nGetSkinCount(JNIEnv* , jclass,
+        jlong nativeAsset) {
+    FilamentAsset* asset = (FilamentAsset*) nativeAsset;
+    return (jint) asset->getSkinCount();
+}
+
+extern "C" JNIEXPORT void JNICALL
+Java_com_google_android_filament_gltfio_FilamentAsset_nGetSkinNames(JNIEnv* env, jclass,
+        jlong nativeAsset, jobjectArray result) {
+    FilamentAsset* asset = (FilamentAsset*) nativeAsset;
+    jsize available = env->GetArrayLength(result);
+    for (int i = 0; i < available; ++i) {
+        const char* name = asset->getSkinNameAt(i);
+        if (name) {
+            env->SetObjectArrayElement(result, (jsize) i, env->NewStringUTF(name));
+        }
+    }
+}
+
+extern "C" JNIEXPORT jint JNICALL
+Java_com_google_android_filament_gltfio_FilamentAsset_nGetJointCountAt(JNIEnv* , jclass,
+        jlong nativeAsset, jint skinIndex) {
+    FilamentAsset* asset = (FilamentAsset*) nativeAsset;
+    return (jint) asset->getJointCountAt(skinIndex);
+}
+
+extern "C" JNIEXPORT void JNICALL
+Java_com_google_android_filament_gltfio_FilamentAsset_nGetJointsAt(JNIEnv* env, jclass,
+        jlong nativeAsset, jint skinIndex, jintArray result) {
+    FilamentAsset* asset = (FilamentAsset*) nativeAsset;
+    jsize available = env->GetArrayLength(result);
+    Entity* entities = (Entity*) env->GetIntArrayElements(result, nullptr);
+    std::copy_n(asset->getJointsAt(skinIndex),
+        std::min(available, (jsize) asset->getJointCountAt(skinIndex)), entities);
+    env->ReleaseIntArrayElements(result, (jint*) entities, 0);
+}
+
 extern "C" JNIEXPORT jlong JNICALL
 Java_com_google_android_filament_gltfio_FilamentAsset_nGetAnimator(JNIEnv* , jclass,
         jlong nativeAsset) {

android/gltfio-android/src/main/cpp/ResourceLoader.cpp

@@ -19,6 +19,7 @@
 #include <filament/Engine.h>
 
 #include <gltfio/ResourceLoader.h>
+#include <gltfio/TextureProvider.h>
 
 #include <utils/Log.h>
 
@@ -114,3 +115,27 @@ Java_com_google_android_filament_gltfio_ResourceLoader_nAsyncCancelLoad(JNIEnv*,
     ResourceLoader* loader = (ResourceLoader*) nativeLoader;
     loader->asyncCancelLoad();
 }
+
+extern "C" JNIEXPORT jlong JNICALL
+Java_com_google_android_filament_gltfio_ResourceLoader_nCreateTextureProvider(JNIEnv*, jclass,
+        jlong nativeEngine) {
+    Engine* engine = (Engine*) nativeEngine;
+    return (jlong) createStbProvider(engine);
+}
+
+extern "C" JNIEXPORT void JNICALL
+Java_com_google_android_filament_gltfio_ResourceLoader_nDestroyTextureProvider(JNIEnv*, jclass,
+        jlong nativeProvider) {
+    TextureProvider* provider = (TextureProvider*) nativeProvider;
+    delete provider;
+}
+
+extern "C" JNIEXPORT void JNICALL
+Java_com_google_android_filament_gltfio_ResourceLoader_nAddTextureProvider(JNIEnv* env, jclass,
+        jlong nativeLoader, jstring url, jlong nativeProvider) {
+    ResourceLoader* loader = (ResourceLoader*) nativeLoader;
+    TextureProvider* provider = (TextureProvider*) nativeProvider;
+    const char* cstring = env->GetStringUTFChars(url, nullptr);
+    loader->addTextureProvider(cstring, provider);
+    env->ReleaseStringUTFChars(url, cstring);
+}

android/gltfio-android/src/main/java/com/google/android/filament/gltfio/Animator.java

@@ -66,6 +66,15 @@ public class Animator {
         nUpdateBoneMatrices(getNativeObject());
     }
 
+    /**
+     * Pass the identity matrix into all bone nodes, useful for returning to the T pose.
+     *
+     * <p>NOTE: this operation is independent of <code>animation</code>.</p>
+     */
+    public void resetBoneMatrices() {
+        nResetBoneMatrices(getNativeObject());
+    }
+
     /**
      * Returns the number of <code>animation</code> definitions in the glTF asset.
      */
@@ -109,6 +118,7 @@ public class Animator {
 
     private static native void nApplyAnimation(long nativeAnimator, int index, float time);
     private static native void nUpdateBoneMatrices(long nativeAnimator);
+    private static native void nResetBoneMatrices(long nativeAnimator);
     private static native int nGetAnimationCount(long nativeAnimator);
     private static native float nGetAnimationDuration(long nativeAnimator, int index);
     private static native String nGetAnimationName(long nativeAnimator, int index);

android/gltfio-android/src/main/java/com/google/android/filament/gltfio/FilamentAsset.java

@@ -216,6 +216,38 @@ public class FilamentAsset {
         return mAnimator;
     }
 
+    /**
+     * Gets the skin count of this asset.
+     */
+    public int getSkinCount() {
+        return nGetSkinCount(getNativeObject());
+    }
+
+    /**
+     * Gets the skin name at skin index in this asset.
+     */
+    public @NonNull String[] getSkinNames() {
+        String[] result = new String[getSkinCount()];
+        nGetSkinNames(getNativeObject(), result);
+        return result;
+    }
+
+    /**
+     * Gets the joint count at skin index in this asset.
+     */
+    public int getJointCountAt(int skinIndex) {
+        return nGetJointCountAt(getNativeObject(), skinIndex);
+    }
+
+    /**
+     * Gets joints at skin index in this asset.
+     */
+    public @NonNull @Entity int[] getJointsAt(int skinIndex) {
+        int[] result = new int[getJointCountAt(skinIndex)];
+        nGetJointsAt(getNativeObject(), skinIndex, result);
+        return result;
+    }
+
     /**
      * Gets the names of all morph targets in the given entity.
      */
@@ -306,6 +338,10 @@ public class FilamentAsset {
     private static native String nGetExtras(long nativeAsset, int entity);
     private static native long nGetAnimator(long nativeAsset);
     private static native void nApplyMaterialVariant(long nativeAsset, int variantIndex);
+    private static native int nGetSkinCount(long nativeAsset);
+    private static native void nGetSkinNames(long nativeAsset, String[] result);
+    private static native int nGetJointCountAt(long nativeAsset, int skinIndex);
+    private static native void nGetJointsAt(long nativeAsset, int skinIndex, int[] result);
     private static native int nGetResourceUriCount(long nativeAsset);
     private static native void nGetResourceUris(long nativeAsset, String[] result);
     private static native void nReleaseSourceData(long nativeAsset);

android/gltfio-android/src/main/java/com/google/android/filament/gltfio/ResourceLoader.java

@@ -35,6 +35,7 @@ import java.nio.Buffer;
  */
 public class ResourceLoader {
     private final long mNativeObject;
+    private final long mNativeProvider;
 
     /**
      * Constructs a resource loader tied to the given Filament engine.
@@ -46,6 +47,9 @@ public class ResourceLoader {
     public ResourceLoader(@NonNull Engine engine) {
         long nativeEngine = engine.getNativeObject();
         mNativeObject = nCreateResourceLoader(nativeEngine, false, false, false);
+        mNativeProvider = nCreateTextureProvider(nativeEngine);
+        nAddTextureProvider(mNativeObject, "image/jpeg", mNativeProvider);
+        nAddTextureProvider(mNativeObject, "image/png", mNativeProvider);
     }
 
     /**
@@ -63,6 +67,9 @@ public class ResourceLoader {
         long nativeEngine = engine.getNativeObject();
         mNativeObject = nCreateResourceLoader(nativeEngine, normalizeSkinningWeights,
                 recomputeBoundingBoxes, ignoreBindTransform);
+        mNativeProvider = nCreateTextureProvider(nativeEngine);
+        nAddTextureProvider(mNativeObject, "image/jpeg", mNativeProvider);
+        nAddTextureProvider(mNativeObject, "image/png", mNativeProvider);
     }
 
     /**
@@ -70,6 +77,7 @@ public class ResourceLoader {
      */
     public void destroy() {
         nDestroyResourceLoader(mNativeObject);
+        nDestroyTextureProvider(mNativeProvider);
     }
 
     /**
@@ -178,4 +186,8 @@ public class ResourceLoader {
     private static native float nAsyncGetLoadProgress(long nativeLoader);
     private static native void nAsyncUpdateLoad(long nativeLoader);
     private static native void nAsyncCancelLoad(long nativeLoader);
+
+    private static native long nCreateTextureProvider(long nativeEngine);
+    private static native void nAddTextureProvider(long nativeLoader, String url, long nativeProvider);
+    private static native void nDestroyTextureProvider(long nativeProvider);
 }

android/gradle.properties

@@ -1,5 +1,5 @@
 GROUP=com.google.android.filament
-VERSION_NAME=1.21.0
+VERSION_NAME=1.21.3
 
 POM_DESCRIPTION=Real-time physically based rendering engine for Android.
 

android/samples/sample-gltf-viewer/src/main/java/com/google/android/filament/gltf/MainActivity.kt

@@ -150,12 +150,12 @@ class MainActivity : Activity() {
         val scene = modelViewer.scene
         val ibl = "default_env"
         readCompressedAsset("envs/$ibl/${ibl}_ibl.ktx").let {
-            scene.indirectLight = KTXLoader.createIndirectLight(engine, it)
+            scene.indirectLight = KTX1Loader.createIndirectLight(engine, it)
             scene.indirectLight!!.intensity = 30_000.0f
             viewerContent.indirectLight = modelViewer.scene.indirectLight
         }
         readCompressedAsset("envs/$ibl/${ibl}_skybox.ktx").let {
-            scene.skybox = KTXLoader.createSkybox(engine, it)
+            scene.skybox = KTX1Loader.createSkybox(engine, it)
         }
     }
 
@@ -297,9 +297,10 @@ class MainActivity : Activity() {
 
         val gltfBuffer = pathToBufferMapping[gltfPath]!!
 
-        // The gltf is often not at the root level (e.g. if a folder is zipped) so
-        // we need to extract its path in order to resolve the embedded uri strings.
-        var prefix = URI(gltfPath!!).resolve("..")
+        // In a zip file, the gltf file might be in the same folder as resources, or in a different
+        // folder. It is crucial to test against both of these cases. In any case, the resource
+        // paths are all specified relative to the location of the gltf file.
+        var prefix = URI(gltfPath!!).resolve(".")
 
         withContext(Dispatchers.Main) {
             if (gltfPath!!.endsWith(".glb")) {
@@ -308,7 +309,7 @@ class MainActivity : Activity() {
                 modelViewer.loadModelGltf(gltfBuffer) { uri ->
                     val path = prefix.resolve(uri).toString()
                     if (!pathToBufferMapping.contains(path)) {
-                        Log.e(TAG, "Could not find '$uri' in zip using prefix '$prefix'")
+                        Log.e(TAG, "Could not find '$uri' in zip using prefix '$prefix' and base path '${gltfPath!!}'")
                         setStatusText("Zip is missing $path")
                     }
                     pathToBufferMapping[path]

android/samples/sample-stream-test/src/main/java/com/google/android/filament/streamtest/MainActivity.kt

@@ -79,8 +79,6 @@ class MainActivity : Activity(), ActivityCompat.OnRequestPermissionsResultCallba
     // Performs the rendering and schedules new frames
     private val frameScheduler = FrameCallback()
 
-    private var externalTextureID: Int = 0
-
     @RequiresApi(30)
     class Api30Impl {
         companion object {
@@ -103,8 +101,6 @@ class MainActivity : Activity(), ActivityCompat.OnRequestPermissionsResultCallba
         setupView()
         setupScene()
 
-        externalTextureID = createExternalTexture()
-
         @Suppress("deprecation")
         val display = if (Build.VERSION.SDK_INT >= 30) {
             Api30Impl.getDisplay(this)
@@ -112,7 +108,7 @@ class MainActivity : Activity(), ActivityCompat.OnRequestPermissionsResultCallba
             windowManager.defaultDisplay!!
         }
 
-        streamHelper = StreamHelper(engine, materialInstance, display, externalTextureID)
+        streamHelper = StreamHelper(engine, materialInstance, display)
         this.title = streamHelper.getTestName()
     }
 
@@ -445,31 +441,4 @@ class MainActivity : Activity(), ActivityCompat.OnRequestPermissionsResultCallba
         check(EGL14.eglMakeCurrent(display, surface, surface, context)) { "Error making GL context." }
         return context
     }
-
-    private  fun createExternalTexture(): Int {
-        val textures = IntArray(1)
-        GLES30.glGenTextures(1, textures, 0)
-        val result = textures[0]
-
-        val textureTarget = GLES11Ext.GL_TEXTURE_EXTERNAL_OES
-        GLES30.glBindTexture(textureTarget, result)
-        GLES30.glTexParameteri(textureTarget, GLES30.GL_TEXTURE_WRAP_S, GLES30.GL_CLAMP_TO_EDGE)
-        GLES30.glTexParameteri(textureTarget, GLES30.GL_TEXTURE_WRAP_T, GLES30.GL_CLAMP_TO_EDGE)
-        GLES30.glTexParameteri(textureTarget, GLES30.GL_TEXTURE_MIN_FILTER, GLES30.GL_NEAREST)
-        GLES30.glTexParameteri(textureTarget, GLES30.GL_TEXTURE_MAG_FILTER, GLES30.GL_NEAREST)
-
-        if (!GLES30.glIsTexture(result)) {
-            throw RuntimeException("OpenGL error: $result is an invalid texture.")
-        }
-
-        val error = GLES30.glGetError()
-        if (error != GLES30.GL_NO_ERROR) {
-            val errorString = GLU.gluErrorString(error)
-            throw RuntimeException("OpenGL error: $errorString!")
-        }
-
-        return result
-    }
-
-
 }

android/samples/sample-stream-test/src/main/java/com/google/android/filament/streamtest/StreamHelper.kt

@@ -37,7 +37,6 @@ class StreamHelper(
     private val filamentEngine: Engine,
     private val filamentMaterial: MaterialInstance,
     private val display: Display,
-    private val externalTextureId: Int
 ) {
     /**
      * The StreamSource configures the source data for the texture.
@@ -51,7 +50,6 @@ class StreamHelper(
      */
     enum class StreamSource {
         CANVAS_STREAM_NATIVE,     // copy-free but does not guarantee synchronization
-        CANVAS_STREAM_TEXID,      // synchronized but incurs a copy
         CANVAS_STREAM_ACQUIRED,   // synchronized and copy-free
     }
 
@@ -127,10 +125,6 @@ class StreamHelper(
 
             surface.unlockCanvasAndPost(canvas)
 
-            if (streamSource == StreamSource.CANVAS_STREAM_TEXID) {
-                surfaceTexture!!.updateTexImage()
-            }
-
             if (streamSource == StreamSource.CANVAS_STREAM_ACQUIRED) {
                 val image = imageReader!!.acquireLatestImage()
                 filamentStream!!.setAcquiredImage(
@@ -146,7 +140,7 @@ class StreamHelper(
 
     fun nextTest() {
         stopTest()
-        streamSource = StreamSource.values()[(streamSource.ordinal + 1) % 3]
+        streamSource = StreamSource.values()[(streamSource.ordinal + 1) % StreamSource.values().size]
         startTest()
     }
 
@@ -213,23 +207,6 @@ class StreamHelper(
             filamentTexture.setExternalStream(filamentEngine, filamentStream!!)
         }
 
-        if (streamSource == StreamSource.CANVAS_STREAM_TEXID) {
-
-            // Create the Android surface that will hold the canvas image.
-            surfaceTexture = SurfaceTexture(externalTextureId)
-            surfaceTexture!!.setDefaultBufferSize(resolution.width, resolution.height)
-            canvasSurface = Surface(surfaceTexture)
-
-            // Create the Filament Stream object that gets bound to the Texture.
-            filamentStream = Stream.Builder()
-                    .stream(externalTextureId.toLong())
-                    .width(resolution.width)
-                    .height(resolution.height)
-                    .build(filamentEngine)
-
-            filamentTexture.setExternalStream(filamentEngine, filamentStream!!)
-        }
-
         if (streamSource == StreamSource.CANVAS_STREAM_ACQUIRED) {
             filamentStream = Stream.Builder()
                     .width(resolution.width)

build.sh

@@ -98,9 +98,9 @@ function print_matdbg_help {
     echo ""
     echo "FOR ANDROID BUILDS:"
     echo ""
-    echo "1) The most reliable way to enable matdbg is to bypass Gradle and"
-    echo "   directly modify the appropriate two lines in the following file:"
-    echo "       ./android/filament-android/CMakeLists.txt"
+    echo "1) For Android Studio builds, make sure to set:"
+    echo "       -Pcom.google.android.filament.matdbg"
+    echo "   option in Preferences > Build > Compiler > Command line options."
     echo ""
     echo "2) The port number is hardcoded to 8081 so you will need to do:"
     echo "       adb forward tcp:8081 tcp:8081"
@@ -156,6 +156,7 @@ VULKAN_ANDROID_GRADLE_OPTION=""
 SWIFTSHADER_OPTION="-DFILAMENT_USE_SWIFTSHADER=OFF"
 
 MATDBG_OPTION="-DFILAMENT_ENABLE_MATDBG=OFF"
+MATDBG_GRADLE_OPTION=""
 
 IOS_BUILD_SIMULATOR=false
 BUILD_UNIVERSAL_LIBRARIES=false
@@ -303,7 +304,7 @@ function build_webgl_with_target {
 }
 
 function build_webgl {
-    # For the host tools, supress install and always use Release.
+    # For the host tools, suppress install and always use Release.
     local old_install_command=${INSTALL_COMMAND}; INSTALL_COMMAND=
     local old_issue_debug_build=${ISSUE_DEBUG_BUILD}; ISSUE_DEBUG_BUILD=false
     local old_issue_release_build=${ISSUE_RELEASE_BUILD}; ISSUE_RELEASE_BUILD=true
@@ -402,7 +403,7 @@ function ensure_android_build {
 function build_android {
     ensure_android_build
 
-    # Supress intermediate desktop tools install
+    # Suppress intermediate desktop tools install
     local old_install_command=${INSTALL_COMMAND}
     INSTALL_COMMAND=
 
@@ -456,6 +457,7 @@ function build_android {
             -Pcom.google.android.filament.dist-dir=../out/android-debug/filament \
             -Pcom.google.android.filament.abis=${ABI_GRADLE_OPTION} \
             ${VULKAN_ANDROID_GRADLE_OPTION} \
+            ${MATDBG_GRADLE_OPTION} \
             :filament-android:assembleDebug \
             :gltfio-android:assembleDebug \
             :filament-utils-android:assembleDebug
@@ -504,6 +506,7 @@ function build_android {
             -Pcom.google.android.filament.dist-dir=../out/android-release/filament \
             -Pcom.google.android.filament.abis=${ABI_GRADLE_OPTION} \
             ${VULKAN_ANDROID_GRADLE_OPTION} \
+            ${MATDBG_GRADLE_OPTION} \
             :filament-android:assembleRelease \
             :gltfio-android:assembleRelease \
             :filament-utils-android:assembleRelease
@@ -598,7 +601,7 @@ function archive_ios {
 }
 
 function build_ios {
-    # Supress intermediate desktop tools install
+    # Suppress intermediate desktop tools install
     local old_install_command=${INSTALL_COMMAND}
     INSTALL_COMMAND=
 
@@ -754,6 +757,7 @@ while getopts ":hacCfijmp:q:uvslwtdk:" opt; do
         d)
             PRINT_MATDBG_HELP=true
             MATDBG_OPTION="-DFILAMENT_ENABLE_MATDBG=ON, -DFILAMENT_DISABLE_MATOPT=ON, -DFILAMENT_BUILD_FILAMAT=ON"
+            MATDBG_GRADLE_OPTION="-Pcom.google.android.filament.matdbg"
             ;;
         f)
             ISSUE_CMAKE_ALWAYS=true

build/common/requirements.txt

@@ -0,0 +1,14 @@
+setuptools==40.6.2
+wheel==0.37.1
+certifi==2021.10.8
+cffi==1.15.0
+charset-normalizer==2.0.12
+Deprecated==1.2.13
+idna==3.3
+pycparser==2.21
+PyGithub==1.55
+PyJWT==2.3.0
+PyNaCl==1.5.0
+requests==2.27.1
+urllib3==1.26.9
+wrapt==1.14.0

build/common/test_list.txt

@@ -11,3 +11,4 @@ tools/cmgen/test_cmgen compare
 tools/glslminifier/test_glslminifier
 libs/filameshio/test_filameshio
 libs/camutils/test_camutils
+libs/ktxreader/test_ktxreader

build/common/upload-assets.py

@@ -12,6 +12,25 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+
+# requirements.txt created via:
+#
+# pip3 install virtualenv
+# python3 -m venv env
+# pip3 install PyGithub
+# pip3 install wheel
+# --all includes wheel and setuputils, which is needed for GitHub Actions
+# pip3 freeze --all > requirements.txt
+# Manually move 'setuptools' and 'wheel' lines to the beginning of the file.
+# Manually remove the 'pip' line.
+#
+# Requirements are installed in GitHub Actions via:
+# xargs -L 1 sudo pip3 install < build/common/requirements.txt
+# xargs must be used because the ordering of the dependencies matters (namely, setuptools).
+# sudo must be used to uninstall non-matching versions of packages.
+# pip is removed to avoid conflicts with the pre-installed pip version on Actions.
+# This technique does not work with Windows, unfortunately.
+
 from github import Github
 import os, sys
 

docs/webgl/demo_redball.html

@@ -12,7 +12,7 @@
 </head>
 <body>
     <canvas></canvas>
-    <script src="//unpkg.com/filament@1.15.0/filament.js"></script>
+    <script src="filament.js"></script>
     <script src="//unpkg.com/gl-matrix@2.8.1"></script>
     <script src="//unpkg.com/gltumble"></script>
     <script src="tutorial_redball.js"></script>

docs/webgl/demo_suzanne.html

@@ -12,7 +12,7 @@
 </head>
 <body>
     <canvas></canvas>
-    <script src="//unpkg.com/filament@1.15.0/filament.js"></script>
+    <script src="filament.js"></script>
     <script src="//unpkg.com/gl-matrix@2.8.1"></script>
     <script src="//unpkg.com/gltumble"></script>
     <script src="tutorial_suzanne.js"></script>

docs/webgl/demo_triangle.html

@@ -12,7 +12,7 @@
 </head>
 <body>
     <canvas></canvas>
-    <script src="//unpkg.com/filament@1.15.0/filament.js"></script>
+    <script src="filament.js"></script>
     <script src="//unpkg.com/gl-matrix@2.8.1"></script>
     <script src="//unpkg.com/gltumble"></script>
     <script src="tutorial_triangle.js"></script>

docs/webgl/reference.html

@@ -64,7 +64,7 @@
 <td align="left">Array of 16-bit or 32-bit unsigned integers consumed by the GPU.</td>
 </tr>
 <tr>
-<td align="left"><a href="#KtxBundle">KtxBundle</a></td>
+<td align="left"><a href="#Ktx1Bundle">Ktx1Bundle</a></td>
 <td align="left">In-memory representation of a KTX file.</td>
 </tr>
 <tr>
@@ -583,6 +583,11 @@
 <li><em>overrides</em> Dictionary with one or more of the following properties: enabled, sampleCount, customResolve.</li>
 </ul>
 </li>
+<li><strong>engine.setScreenSpaceReflectionsOptions(overrides)</strong>
+<ul>
+<li><em>overrides</em> Dictionary with one or more of the following properties: thickness, bias, maxDistance, stride, enabled.</li>
+</ul>
+</li>
 <li><strong>engine.setShadowOptions(instance, overrides)</strong>
 <ul>
 <li><em>instance</em> Instance of a light component obtained from <code>getInstance</code>.</li>
@@ -662,63 +667,63 @@ as quaternions.</li>
 </ul>
 </div>
 <div class='classdoc'>
-<h2>class <a id='KtxBundle' href='#KtxBundle'>KtxBundle</a></h2>
+<h2>class <a id='Ktx1Bundle' href='#Ktx1Bundle'>Ktx1Bundle</a></h2>
 <p>In-memory representation of a KTX file.</p>
 <ul>
-<li><strong>ktxBundle.getArrayLength()</strong>
+<li><strong>ktx1Bundle.getArrayLength()</strong>
 <ul>
 <li>Obtains length of the texture array.</li>
 <li><em>returns</em> The number of elements in the texture array</li>
 </ul>
 </li>
-<li><strong>ktxBundle.getCompressedPixelDataType()</strong>
+<li><strong>ktx1Bundle.getCompressedPixelDataType()</strong>
 <ul>
 <li><em>returns</em> <a href="#CompressedPixelDataType">CompressedPixelDataType</a></li>
 </ul>
 </li>
-<li><strong>ktxBundle.getInternalFormat(srgb)</strong>
+<li><strong>ktx1Bundle.getInternalFormat(srgb)</strong>
 <ul>
 <li><em>srgb</em> boolean that forces the resulting format to SRGB if possible.</li>
 <li><em>returns</em> <a href="#Texture%24InternalFormat">Texture$InternalFormat</a></li>
 </ul>
 </li>
-<li><strong>ktxBundle.getMetadata(key)</strong>
+<li><strong>ktx1Bundle.getMetadata(key)</strong>
 <ul>
 <li>Obtains arbitrary metadata from the KTX file.</li>
 <li><em>key</em> string</li>
 <li><em>returns</em> string</li>
 </ul>
 </li>
-<li><strong>ktxBundle.getPixelDataFormat()</strong>
+<li><strong>ktx1Bundle.getPixelDataFormat()</strong>
 <ul>
 <li><em>returns</em> <a href="#PixelDataFormat">PixelDataFormat</a></li>
 </ul>
 </li>
-<li><strong>ktxBundle.getPixelDataType()</strong>
+<li><strong>ktx1Bundle.getPixelDataType()</strong>
 <ul>
 <li><em>returns</em> <a href="#PixelDataType">PixelDataType</a></li>
 </ul>
 </li>
-<li><strong>ktxBundle.info()</strong>
+<li><strong>ktx1Bundle.info()</strong>
 <ul>
 <li>Obtains properties of the KTX header.</li>
 <li><em>returns</em> The <a href="#KtxInfo">KtxInfo</a> property accessor object.</li>
 </ul>
 </li>
-<li><strong>ktxBundle.info()</strong>
+<li><strong>ktx1Bundle.info()</strong>
 <ul>
 <li>Obtains properties of the KTX header.</li>
 <li><em>returns</em> The <a href="#KtxInfo">KtxInfo</a> property accessor object.</li>
 </ul>
 </li>
-<li><strong>ktxBundle.isCompressed()</strong>
+<li><strong>ktx1Bundle.isCompressed()</strong>
 <ul>
 <li><em>returns</em> boolean</li>
 </ul>
 </li>
 </ul>
 <p>Most clients should use one of the <code>create*FromKtx</code> utility methods in the JavaScript <a href="#Engine">Engine</a>
-wrapper rather than interacting with <code>KtxBundle</code> directly.</p>
+wrapper rather than interacting with <code>Ktx1Bundle</code> directly.</p>
 </div>
 <div class='classdoc'>
 <h2>class <a id='KtxInfo' href='#KtxInfo'>KtxInfo</a></h2>
@@ -743,7 +748,7 @@ wrapper rather than interacting with <code>KtxBundle</code> directly.</p>
 </ul>
 </li>
 </ul>
-<p>For example, <code>ktxbundle.info().pixelWidth</code>. See the
+<p>For example, <code>Ktx1Bundle.info().pixelWidth</code>. See the
 <a href="https://www.khronos.org/opengles/sdk/tools/KTX/file_format_spec/">KTX spec</a> for the list of
 properties.</p>
 </div>
@@ -1267,7 +1272,9 @@ This defines the following functions:</p>
 <ul>
 <li>POINTS</li>
 <li>LINES</li>
+<li>LINE_STRIP</li>
 <li>TRIANGLES</li>
+<li>TRIANGLE_STRIP</li>
 <li>NONE</li>
 </ul>
 </div>

docs/webgl/tutorial_redball.html

@@ -12,7 +12,9 @@ textures.</p>
 <a href="tutorial_triangle.html">previous tutorial</a>. Change the last script tag from <code>triangle.js</code> to <code>redball.js</code>.</p>
 <p>Next you'll need to get a couple command-line tools: <code>matc</code> and <code>cmgen</code>. You can find these in the
 appropriate <a href="//github.com/google/filament/releases">Filament release</a>. You should choose the
-archive that corresponds to your development machine rather than the one for web.</p>
+archive that corresponds to your development machine rather than the one for web, and the version
+that matches the <code>unpkg.com/filament@x.x.x</code> url in the script tag of <code>redball.html</code> (you may check
+out the last available release of <a href="https://www.npmjs.com/package/filament">filament on npm</a>).</p>
 <h2>Define plastic material</h2>
 <p>The <code>matc</code> tool consumes a text file containing a high-level description of a PBR material, and
 produces a binary material package that contains shader code and associated metadata. For more
@@ -60,12 +62,12 @@ IBL KTX contains these coefficients in its metadata.</p>
 <h2>Create JavaScript</h2>
 <p>Next, create <code>redball.js</code> with the following content.</p>
 <div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #008000; font-weight: bold">const</span> environ <span style="color: #666666">=</span> <span style="color: #BA2121">&#39;pillars_2k&#39;</span>;
-<span style="color: #008000; font-weight: bold">const</span> ibl_url <span style="color: #666666">=</span> <span style="color: #BA2121">`</span><span style="color: #BB6688; font-weight: bold">${</span>environ<span style="color: #BB6688; font-weight: bold">}</span><span style="color: #BA2121">/</span><span style="color: #BB6688; font-weight: bold">${</span>environ<span style="color: #BB6688; font-weight: bold">}</span><span style="color: #BA2121">_ibl.ktx`</span>;
-<span style="color: #008000; font-weight: bold">const</span> sky_url <span style="color: #666666">=</span> <span style="color: #BA2121">`</span><span style="color: #BB6688; font-weight: bold">${</span>environ<span style="color: #BB6688; font-weight: bold">}</span><span style="color: #BA2121">/</span><span style="color: #BB6688; font-weight: bold">${</span>environ<span style="color: #BB6688; font-weight: bold">}</span><span style="color: #BA2121">_skybox.ktx`</span>;
+<span style="color: #008000; font-weight: bold">const</span> ibl_url <span style="color: #666666">=</span> <span style="color: #BA2121">`</span><span style="color: #A45A77; font-weight: bold">${</span>environ<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">/</span><span style="color: #A45A77; font-weight: bold">${</span>environ<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">_ibl.ktx`</span>;
+<span style="color: #008000; font-weight: bold">const</span> sky_url <span style="color: #666666">=</span> <span style="color: #BA2121">`</span><span style="color: #A45A77; font-weight: bold">${</span>environ<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">/</span><span style="color: #A45A77; font-weight: bold">${</span>environ<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">_skybox.ktx`</span>;
 <span style="color: #008000; font-weight: bold">const</span> filamat_url <span style="color: #666666">=</span> <span style="color: #BA2121">&#39;plastic.filamat&#39;</span>
 
 Filament.init([ filamat_url, ibl_url, sky_url ], () =&gt; {
-  <span style="color: #408080; font-style: italic">// Create some global aliases to enums for convenience.</span>
+  <span style="color: #3D7B7B; font-style: italic">// Create some global aliases to enums for convenience.</span>
   <span style="color: #008000">window</span>.VertexAttribute <span style="color: #666666">=</span> Filament.VertexAttribute;
   <span style="color: #008000">window</span>.AttributeType <span style="color: #666666">=</span> Filament.VertexBuffer$AttributeType;
   <span style="color: #008000">window</span>.PrimitiveType <span style="color: #666666">=</span> Filament.RenderableManager$PrimitiveType;
@@ -73,7 +75,7 @@ Filament.init([ filamat_url, ibl_url, sky_url ], () =&gt; {
   <span style="color: #008000">window</span>.Fov <span style="color: #666666">=</span> Filament.Camera$Fov;
   <span style="color: #008000">window</span>.LightType <span style="color: #666666">=</span> Filament.LightManager$Type;
 
-  <span style="color: #408080; font-style: italic">// Obtain the canvas DOM object and pass it to the App.</span>
+  <span style="color: #3D7B7B; font-style: italic">// Obtain the canvas DOM object and pass it to the App.</span>
   <span style="color: #008000; font-weight: bold">const</span> canvas <span style="color: #666666">=</span> <span style="color: #008000">document</span>.getElementsByTagName(<span style="color: #BA2121">&#39;canvas&#39;</span>)[<span style="color: #666666">0</span>];
   <span style="color: #008000">window</span>.app <span style="color: #666666">=</span> <span style="color: #AA22FF; font-weight: bold">new</span> App(canvas);
 } );
@@ -84,11 +86,11 @@ Filament.init([ filamat_url, ibl_url, sky_url ], () =&gt; {
     <span style="color: #008000; font-weight: bold">const</span> engine <span style="color: #666666">=</span> <span style="color: #008000; font-weight: bold">this</span>.engine <span style="color: #666666">=</span> Filament.Engine.create(canvas);
     <span style="color: #008000; font-weight: bold">const</span> scene <span style="color: #666666">=</span> engine.createScene();
 
-    <span style="color: #408080; font-style: italic">// TODO: create material</span>
-    <span style="color: #408080; font-style: italic">// TODO: create sphere</span>
-    <span style="color: #408080; font-style: italic">// TODO: create lights</span>
-    <span style="color: #408080; font-style: italic">// TODO: create IBL</span>
-    <span style="color: #408080; font-style: italic">// TODO: create skybox</span>
+    <span style="color: #3D7B7B; font-style: italic">// TODO: create material</span>
+    <span style="color: #3D7B7B; font-style: italic">// TODO: create sphere</span>
+    <span style="color: #3D7B7B; font-style: italic">// TODO: create lights</span>
+    <span style="color: #3D7B7B; font-style: italic">// TODO: create IBL</span>
+    <span style="color: #3D7B7B; font-style: italic">// TODO: create skybox</span>
 
     <span style="color: #008000; font-weight: bold">this</span>.swapChain <span style="color: #666666">=</span> engine.createSwapChain();
     <span style="color: #008000; font-weight: bold">this</span>.renderer <span style="color: #666666">=</span> engine.createRenderer();
@@ -209,9 +211,9 @@ following (don't type this out, there's an easier way).</p>
 <div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #008000; font-weight: bold">const</span> format <span style="color: #666666">=</span> Filament.PixelDataFormat.RGB;
 <span style="color: #008000; font-weight: bold">const</span> datatype <span style="color: #666666">=</span> Filament.PixelDataType.UINT_10F_11F_11F_REV;
 
-<span style="color: #408080; font-style: italic">// Create a Texture object for the mipmapped cubemap.</span>
+<span style="color: #3D7B7B; font-style: italic">// Create a Texture object for the mipmapped cubemap.</span>
 <span style="color: #008000; font-weight: bold">const</span> ibl_package <span style="color: #666666">=</span> Filament.Buffer(Filament.assets[ibl_url]);
-<span style="color: #008000; font-weight: bold">const</span> iblktx <span style="color: #666666">=</span> <span style="color: #AA22FF; font-weight: bold">new</span> Filament.KtxBundle(ibl_package);
+<span style="color: #008000; font-weight: bold">const</span> iblktx <span style="color: #666666">=</span> <span style="color: #AA22FF; font-weight: bold">new</span> Filament.Ktx1Bundle(ibl_package);
 
 <span style="color: #008000; font-weight: bold">const</span> ibltex <span style="color: #666666">=</span> Filament.Texture.Builder()
   .width(iblktx.info().pixelWidth)
@@ -227,11 +229,11 @@ following (don't type this out, there's an easier way).</p>
   ibltex.setImageCube(engine, level, pixelbuffer);
 }
 
-<span style="color: #408080; font-style: italic">// Parse the spherical harmonics metadata.</span>
+<span style="color: #3D7B7B; font-style: italic">// Parse the spherical harmonics metadata.</span>
 <span style="color: #008000; font-weight: bold">const</span> shstring <span style="color: #666666">=</span> iblktx.getMetadata(<span style="color: #BA2121">&#39;sh&#39;</span>);
-<span style="color: #008000; font-weight: bold">const</span> shfloats <span style="color: #666666">=</span> shstring.split(<span style="color: #BB6688">/\s/</span>, <span style="color: #666666">9</span> <span style="color: #666666">*</span> <span style="color: #666666">3</span>).map(<span style="color: #008000">parseFloat</span>);
+<span style="color: #008000; font-weight: bold">const</span> shfloats <span style="color: #666666">=</span> shstring.split(<span style="color: #A45A77">/\s/</span>, <span style="color: #666666">9</span> <span style="color: #666666">*</span> <span style="color: #666666">3</span>).map(<span style="color: #008000">parseFloat</span>);
 
-<span style="color: #408080; font-style: italic">// Build the IBL object and insert it into the scene.</span>
+<span style="color: #3D7B7B; font-style: italic">// Build the IBL object and insert it into the scene.</span>
 <span style="color: #008000; font-weight: bold">const</span> indirectLight <span style="color: #666666">=</span> Filament.IndirectLight.Builder()
   .reflections(ibltex)
   .irradianceSh(<span style="color: #666666">3</span>, shfloats)
@@ -253,7 +255,7 @@ scene.setIndirectLight(indirectLight);
 Without a skybox, the reflections on the ball are not representative of its surroundings.
 Here's one way to create a texture for the skybox:</p>
 <div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #008000; font-weight: bold">const</span> sky_package <span style="color: #666666">=</span> Filament.Buffer(Filament.assets[sky_url]);
-<span style="color: #008000; font-weight: bold">const</span> skyktx <span style="color: #666666">=</span> <span style="color: #AA22FF; font-weight: bold">new</span> Filament.KtxBundle(sky_package);
+<span style="color: #008000; font-weight: bold">const</span> skyktx <span style="color: #666666">=</span> <span style="color: #AA22FF; font-weight: bold">new</span> Filament.Ktx1Bundle(sky_package);
 <span style="color: #008000; font-weight: bold">const</span> skytex <span style="color: #666666">=</span> Filament.Texture.Builder()
   .width(skyktx.info().pixelWidth)
   .height(skyktx.info().pixelHeight)

docs/webgl/tutorial_suzanne.html

@@ -22,25 +22,25 @@ converting <a href="https://github.com/google/filament/blob/main/assets/models/m
 <p>Next, let's create mipmapped KTX files using filament's <code>mipgen</code> tool. We'll create compressed and
 non-compressed variants for each texture, since not all platforms support the same compression
 formats. First copy over the PNG files from the <a href="https://github.com/google/filament/blob/main/assets/models/monkey">monkey folder</a>, then do:</p>
-<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #408080; font-style: italic"># Create mipmaps for base color and two compressed variants.</span>
+<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #3D7B7B; font-style: italic"># Create mipmaps for base color and two compressed variants.</span>
 mipgen albedo.png albedo.ktx
 mipgen --compression<span style="color: #666666">=</span>astc_fast_ldr_4x4 albedo.png albedo_astc.ktx
 mipgen --compression<span style="color: #666666">=</span>s3tc_rgb_dxt1 albedo.png albedo_s3tc_srgb.ktx
 
-<span style="color: #408080; font-style: italic"># Create mipmaps for the normal map and a compressed variant.</span>
+<span style="color: #3D7B7B; font-style: italic"># Create mipmaps for the normal map and a compressed variant.</span>
 mipgen --strip-alpha --kernel<span style="color: #666666">=</span>NORMALS --linear normal.png normal.ktx
-mipgen --strip-alpha --kernel<span style="color: #666666">=</span>NORMALS --linear --compression<span style="color: #666666">=</span>etc_rgb8_normalxyz_40 <span style="color: #BB6622; font-weight: bold">\</span>
+mipgen --strip-alpha --kernel<span style="color: #666666">=</span>NORMALS --linear --compression<span style="color: #666666">=</span>etc_rgb8_normalxyz_40 <span style="color: #AA5D1F; font-weight: bold">\</span>
     normal.png normal_etc.ktx
 
-<span style="color: #408080; font-style: italic"># Create mipmaps for the single-component roughness map and a compressed variant.</span>
+<span style="color: #3D7B7B; font-style: italic"># Create mipmaps for the single-component roughness map and a compressed variant.</span>
 mipgen --grayscale roughness.png roughness.ktx
 mipgen --grayscale --compression<span style="color: #666666">=</span>etc_r11_numeric_40 roughness.png roughness_etc.ktx
 
-<span style="color: #408080; font-style: italic"># Create mipmaps for the single-component metallic map and a compressed variant.</span>
+<span style="color: #3D7B7B; font-style: italic"># Create mipmaps for the single-component metallic map and a compressed variant.</span>
 mipgen --grayscale metallic.png metallic.ktx
 mipgen --grayscale --compression<span style="color: #666666">=</span>etc_r11_numeric_40 metallic.png metallic_etc.ktx
 
-<span style="color: #408080; font-style: italic"># Create mipmaps for the single-component occlusion map and a compressed variant.</span>
+<span style="color: #3D7B7B; font-style: italic"># Create mipmaps for the single-component occlusion map and a compressed variant.</span>
 mipgen --grayscale ao.png ao.ktx
 mipgen --grayscale --compression<span style="color: #666666">=</span>etc_r11_numeric_40 ao.png ao_etc.ktx
 </pre></div>
@@ -101,7 +101,7 @@ materials, consult the official document describing the <a href="https://google.
 <p>Create a text file called <code>suzanne.html</code> and copy over the HTML that we used in the <a href="tutorial_redball.html">previous
 tutorial</a>. Change the last script tag from <code>redball.js</code> to <code>suzanne.js</code>. Next, create <code>suzanne.js</code>
 with the following content.</p>
-<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #408080; font-style: italic">// TODO: declare asset URLs</span>
+<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #3D7B7B; font-style: italic">// TODO: declare asset URLs</span>
 
 Filament.init([ filamat_url, filamesh_url, sky_small_url, ibl_url ], () =&gt; {
     <span style="color: #008000">window</span>.app <span style="color: #666666">=</span> <span style="color: #AA22FF; font-weight: bold">new</span> App(<span style="color: #008000">document</span>.getElementsByTagName(<span style="color: #BA2121">&#39;canvas&#39;</span>)[<span style="color: #666666">0</span>]);
@@ -119,9 +119,9 @@ Filament.init([ filamat_url, filamesh_url, sky_small_url, ibl_url ], () =&gt; {
         <span style="color: #008000; font-weight: bold">const</span> filamesh <span style="color: #666666">=</span> <span style="color: #008000; font-weight: bold">this</span>.engine.loadFilamesh(filamesh_url, <span style="color: #008000; font-weight: bold">this</span>.matinstance);
         <span style="color: #008000; font-weight: bold">this</span>.suzanne <span style="color: #666666">=</span> filamesh.renderable;
 
-        <span style="color: #408080; font-style: italic">// TODO: create sky box and IBL</span>
-        <span style="color: #408080; font-style: italic">// TODO: initialize gltumble</span>
-        <span style="color: #408080; font-style: italic">// TODO: fetch larger assets</span>
+        <span style="color: #3D7B7B; font-style: italic">// TODO: create sky box and IBL</span>
+        <span style="color: #3D7B7B; font-style: italic">// TODO: initialize gltumble</span>
+        <span style="color: #3D7B7B; font-style: italic">// TODO: fetch larger assets</span>
 
         <span style="color: #008000; font-weight: bold">this</span>.swapChain <span style="color: #666666">=</span> <span style="color: #008000; font-weight: bold">this</span>.engine.createSwapChain();
         <span style="color: #008000; font-weight: bold">this</span>.renderer <span style="color: #666666">=</span> <span style="color: #008000; font-weight: bold">this</span>.engine.createRenderer();
@@ -141,7 +141,7 @@ Filament.init([ filamat_url, filamesh_url, sky_small_url, ibl_url ], () =&gt; {
     }
 
     render() {
-        <span style="color: #408080; font-style: italic">// TODO: apply gltumble matrix</span>
+        <span style="color: #3D7B7B; font-style: italic">// TODO: apply gltumble matrix</span>
         <span style="color: #008000; font-weight: bold">this</span>.renderer.render(<span style="color: #008000; font-weight: bold">this</span>.swapChain, <span style="color: #008000; font-weight: bold">this</span>.view);
         <span style="color: #008000">window</span>.requestAnimationFrame(<span style="color: #008000; font-weight: bold">this</span>.render);
     }
@@ -176,14 +176,14 @@ last resort. Go ahead and replace the <strong>declare asset URLs</strong> commen
 <span style="color: #008000; font-weight: bold">const</span> texture_suffix <span style="color: #666666">=</span> Filament.getSupportedFormatSuffix(<span style="color: #BA2121">&#39;etc&#39;</span>);
 
 <span style="color: #008000; font-weight: bold">const</span> environ <span style="color: #666666">=</span> <span style="color: #BA2121">&#39;venetian_crossroads_2k&#39;</span>
-<span style="color: #008000; font-weight: bold">const</span> ibl_url <span style="color: #666666">=</span> <span style="color: #BA2121">`</span><span style="color: #BB6688; font-weight: bold">${</span>environ<span style="color: #BB6688; font-weight: bold">}</span><span style="color: #BA2121">/</span><span style="color: #BB6688; font-weight: bold">${</span>environ<span style="color: #BB6688; font-weight: bold">}</span><span style="color: #BA2121">_ibl.ktx`</span>;
-<span style="color: #008000; font-weight: bold">const</span> sky_small_url <span style="color: #666666">=</span> <span style="color: #BA2121">`</span><span style="color: #BB6688; font-weight: bold">${</span>environ<span style="color: #BB6688; font-weight: bold">}</span><span style="color: #BA2121">/</span><span style="color: #BB6688; font-weight: bold">${</span>environ<span style="color: #BB6688; font-weight: bold">}</span><span style="color: #BA2121">_skybox_tiny.ktx`</span>;
-<span style="color: #008000; font-weight: bold">const</span> sky_large_url <span style="color: #666666">=</span> <span style="color: #BA2121">`</span><span style="color: #BB6688; font-weight: bold">${</span>environ<span style="color: #BB6688; font-weight: bold">}</span><span style="color: #BA2121">/</span><span style="color: #BB6688; font-weight: bold">${</span>environ<span style="color: #BB6688; font-weight: bold">}</span><span style="color: #BA2121">_skybox.ktx`</span>;
-<span style="color: #008000; font-weight: bold">const</span> albedo_url <span style="color: #666666">=</span> <span style="color: #BA2121">`albedo</span><span style="color: #BB6688; font-weight: bold">${</span>albedo_suffix<span style="color: #BB6688; font-weight: bold">}</span><span style="color: #BA2121">.ktx`</span>;
-<span style="color: #008000; font-weight: bold">const</span> ao_url <span style="color: #666666">=</span> <span style="color: #BA2121">`ao</span><span style="color: #BB6688; font-weight: bold">${</span>texture_suffix<span style="color: #BB6688; font-weight: bold">}</span><span style="color: #BA2121">.ktx`</span>;
-<span style="color: #008000; font-weight: bold">const</span> metallic_url <span style="color: #666666">=</span> <span style="color: #BA2121">`metallic</span><span style="color: #BB6688; font-weight: bold">${</span>texture_suffix<span style="color: #BB6688; font-weight: bold">}</span><span style="color: #BA2121">.ktx`</span>;
-<span style="color: #008000; font-weight: bold">const</span> normal_url <span style="color: #666666">=</span> <span style="color: #BA2121">`normal</span><span style="color: #BB6688; font-weight: bold">${</span>texture_suffix<span style="color: #BB6688; font-weight: bold">}</span><span style="color: #BA2121">.ktx`</span>;
-<span style="color: #008000; font-weight: bold">const</span> roughness_url <span style="color: #666666">=</span> <span style="color: #BA2121">`roughness</span><span style="color: #BB6688; font-weight: bold">${</span>texture_suffix<span style="color: #BB6688; font-weight: bold">}</span><span style="color: #BA2121">.ktx`</span>;
+<span style="color: #008000; font-weight: bold">const</span> ibl_url <span style="color: #666666">=</span> <span style="color: #BA2121">`</span><span style="color: #A45A77; font-weight: bold">${</span>environ<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">/</span><span style="color: #A45A77; font-weight: bold">${</span>environ<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">_ibl.ktx`</span>;
+<span style="color: #008000; font-weight: bold">const</span> sky_small_url <span style="color: #666666">=</span> <span style="color: #BA2121">`</span><span style="color: #A45A77; font-weight: bold">${</span>environ<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">/</span><span style="color: #A45A77; font-weight: bold">${</span>environ<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">_skybox_tiny.ktx`</span>;
+<span style="color: #008000; font-weight: bold">const</span> sky_large_url <span style="color: #666666">=</span> <span style="color: #BA2121">`</span><span style="color: #A45A77; font-weight: bold">${</span>environ<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">/</span><span style="color: #A45A77; font-weight: bold">${</span>environ<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">_skybox.ktx`</span>;
+<span style="color: #008000; font-weight: bold">const</span> albedo_url <span style="color: #666666">=</span> <span style="color: #BA2121">`albedo</span><span style="color: #A45A77; font-weight: bold">${</span>albedo_suffix<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">.ktx`</span>;
+<span style="color: #008000; font-weight: bold">const</span> ao_url <span style="color: #666666">=</span> <span style="color: #BA2121">`ao</span><span style="color: #A45A77; font-weight: bold">${</span>texture_suffix<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">.ktx`</span>;
+<span style="color: #008000; font-weight: bold">const</span> metallic_url <span style="color: #666666">=</span> <span style="color: #BA2121">`metallic</span><span style="color: #A45A77; font-weight: bold">${</span>texture_suffix<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">.ktx`</span>;
+<span style="color: #008000; font-weight: bold">const</span> normal_url <span style="color: #666666">=</span> <span style="color: #BA2121">`normal</span><span style="color: #A45A77; font-weight: bold">${</span>texture_suffix<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">.ktx`</span>;
+<span style="color: #008000; font-weight: bold">const</span> roughness_url <span style="color: #666666">=</span> <span style="color: #BA2121">`roughness</span><span style="color: #A45A77; font-weight: bold">${</span>texture_suffix<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">.ktx`</span>;
 <span style="color: #008000; font-weight: bold">const</span> filamat_url <span style="color: #666666">=</span> <span style="color: #BA2121">&#39;textured.filamat&#39;</span>;
 <span style="color: #008000; font-weight: bold">const</span> filamesh_url <span style="color: #666666">=</span> <span style="color: #BA2121">&#39;suzanne.filamesh&#39;</span>;
 </pre></div>
@@ -224,7 +224,7 @@ was created in the app constructor.</p>
     <span style="color: #008000; font-weight: bold">this</span>.matinstance.setTextureParameter(<span style="color: #BA2121">&#39;normal&#39;</span>, normal, sampler);
     <span style="color: #008000; font-weight: bold">this</span>.matinstance.setTextureParameter(<span style="color: #BA2121">&#39;ao&#39;</span>, ao, sampler);
 
-    <span style="color: #408080; font-style: italic">// Replace low-res skybox with high-res skybox.</span>
+    <span style="color: #3D7B7B; font-style: italic">// Replace low-res skybox with high-res skybox.</span>
     <span style="color: #008000; font-weight: bold">this</span>.engine.destroySkybox(<span style="color: #008000; font-weight: bold">this</span>.skybox);
     <span style="color: #008000; font-weight: bold">this</span>.skybox <span style="color: #666666">=</span> <span style="color: #008000; font-weight: bold">this</span>.engine.createSkyFromKtx(sky_large_url);
     <span style="color: #008000; font-weight: bold">this</span>.scene.setSkybox(<span style="color: #008000; font-weight: bold">this</span>.skybox);
@@ -236,7 +236,7 @@ was created in the app constructor.</p>
 <h2>Introduce trackball rotation</h2>
 <p>Add the following script tag to your HTML file. This imports a small third-party library that
 listens for drag events and computes a rotation matrix.</p>
-<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span>&lt;<span style="color: #008000; font-weight: bold">script</span> <span style="color: #7D9029">src</span><span style="color: #666666">=</span><span style="color: #BA2121">&quot;//unpkg.com/gltumble&quot;</span>&gt;&lt;/<span style="color: #008000; font-weight: bold">script</span>&gt;
+<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span>&lt;<span style="color: #008000; font-weight: bold">script</span> <span style="color: #687822">src</span><span style="color: #666666">=</span><span style="color: #BA2121">&quot;//unpkg.com/gltumble&quot;</span>&gt;&lt;/<span style="color: #008000; font-weight: bold">script</span>&gt;
 </pre></div>
 
 <p>Next, replace the <strong>initialize gltumble</strong> and <strong>apply gltumble matrix</strong> comments with the following

docs/webgl/tutorial_triangle.html

@@ -16,22 +16,22 @@ subsequent code blocks.</p>
 <h2>Start your project</h2>
 <p>First, create a text file called <code>triangle.html</code> and fill it with the following HTML. This creates
 a mobile-friendly page with a full-screen canvas.</p>
-<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #BC7A00">&lt;!DOCTYPE html&gt;</span>
-&lt;<span style="color: #008000; font-weight: bold">html</span> <span style="color: #7D9029">lang</span><span style="color: #666666">=</span><span style="color: #BA2121">&quot;en&quot;</span>&gt;
+<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #9C6500">&lt;!DOCTYPE html&gt;</span>
+&lt;<span style="color: #008000; font-weight: bold">html</span> <span style="color: #687822">lang</span><span style="color: #666666">=</span><span style="color: #BA2121">&quot;en&quot;</span>&gt;
 &lt;<span style="color: #008000; font-weight: bold">head</span>&gt;
     &lt;<span style="color: #008000; font-weight: bold">title</span>&gt;Filament Tutorial&lt;/<span style="color: #008000; font-weight: bold">title</span>&gt;
-    &lt;<span style="color: #008000; font-weight: bold">meta</span> <span style="color: #7D9029">charset</span><span style="color: #666666">=</span><span style="color: #BA2121">&quot;utf-8&quot;</span>&gt;
-    &lt;<span style="color: #008000; font-weight: bold">meta</span> <span style="color: #7D9029">name</span><span style="color: #666666">=</span><span style="color: #BA2121">&quot;viewport&quot;</span> <span style="color: #7D9029">content</span><span style="color: #666666">=</span><span style="color: #BA2121">&quot;width=device-width,user-scalable=no,initial-scale=1&quot;</span>&gt;
-    &lt;<span style="color: #008000; font-weight: bold">style</span>&gt;
-        <span style="color: #008000; font-weight: bold">body</span> { <span style="color: #008000; font-weight: bold">margin</span>: <span style="color: #666666">0</span>; <span style="color: #008000; font-weight: bold">overflow</span>: <span style="color: #008000; font-weight: bold">hidden</span>; }
-        <span style="color: #008000; font-weight: bold">canvas</span> { touch-action: <span style="color: #008000; font-weight: bold">none</span>; <span style="color: #008000; font-weight: bold">width</span>: <span style="color: #666666">100</span><span style="color: #B00040">%</span>; <span style="color: #008000; font-weight: bold">height</span>: <span style="color: #666666">100</span><span style="color: #B00040">%</span>; }
-    &lt;/<span style="color: #008000; font-weight: bold">style</span>&gt;
+    &lt;<span style="color: #008000; font-weight: bold">meta</span> <span style="color: #687822">charset</span><span style="color: #666666">=</span><span style="color: #BA2121">&quot;utf-8&quot;</span>&gt;
+    &lt;<span style="color: #008000; font-weight: bold">meta</span> <span style="color: #687822">name</span><span style="color: #666666">=</span><span style="color: #BA2121">&quot;viewport&quot;</span> <span style="color: #687822">content</span><span style="color: #666666">=</span><span style="color: #BA2121">&quot;width=device-width,user-scalable=no,initial-scale=1&quot;</span>&gt;
+    &lt;<span style="color: #008000; font-weight: bold">style</span>&gt;<span style="color: #bbbbbb"></span>
+<span style="color: #bbbbbb">        </span><span style="color: #008000; font-weight: bold">body</span><span style="color: #bbbbbb"> </span>{<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">margin</span>:<span style="color: #bbbbbb"> </span><span style="color: #666666">0</span>;<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">overflow</span>:<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">hidden</span>;<span style="color: #bbbbbb"> </span>}<span style="color: #bbbbbb"></span>
+<span style="color: #bbbbbb">        </span><span style="color: #008000; font-weight: bold">canvas</span><span style="color: #bbbbbb"> </span>{<span style="color: #bbbbbb"> </span>touch-action:<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">none</span>;<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">width</span>:<span style="color: #bbbbbb"> </span><span style="color: #666666">100</span><span style="color: #B00040">%</span>;<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">height</span>:<span style="color: #bbbbbb"> </span><span style="color: #666666">100</span><span style="color: #B00040">%</span>;<span style="color: #bbbbbb"> </span>}<span style="color: #bbbbbb"></span>
+<span style="color: #bbbbbb">    </span>&lt;/<span style="color: #008000; font-weight: bold">style</span>&gt;
 &lt;/<span style="color: #008000; font-weight: bold">head</span>&gt;
 &lt;<span style="color: #008000; font-weight: bold">body</span>&gt;
     &lt;<span style="color: #008000; font-weight: bold">canvas</span>&gt;&lt;/<span style="color: #008000; font-weight: bold">canvas</span>&gt;
-    &lt;<span style="color: #008000; font-weight: bold">script</span> <span style="color: #7D9029">src</span><span style="color: #666666">=</span><span style="color: #BA2121">&quot;//unpkg.com/filament@1.15.0/filament.js&quot;</span>&gt;&lt;/<span style="color: #008000; font-weight: bold">script</span>&gt;
-    &lt;<span style="color: #008000; font-weight: bold">script</span> <span style="color: #7D9029">src</span><span style="color: #666666">=</span><span style="color: #BA2121">&quot;//unpkg.com/gl-matrix@2.8.1&quot;</span>&gt;&lt;/<span style="color: #008000; font-weight: bold">script</span>&gt;
-    &lt;<span style="color: #008000; font-weight: bold">script</span> <span style="color: #7D9029">src</span><span style="color: #666666">=</span><span style="color: #BA2121">&quot;triangle.js&quot;</span>&gt;&lt;/<span style="color: #008000; font-weight: bold">script</span>&gt;
+    &lt;<span style="color: #008000; font-weight: bold">script</span> <span style="color: #687822">src</span><span style="color: #666666">=</span><span style="color: #BA2121">&quot;filament.js&quot;</span>&gt;&lt;/<span style="color: #008000; font-weight: bold">script</span>&gt;
+    &lt;<span style="color: #008000; font-weight: bold">script</span> <span style="color: #687822">src</span><span style="color: #666666">=</span><span style="color: #BA2121">&quot;//unpkg.com/gl-matrix@2.8.1&quot;</span>&gt;&lt;/<span style="color: #008000; font-weight: bold">script</span>&gt;
+    &lt;<span style="color: #008000; font-weight: bold">script</span> <span style="color: #687822">src</span><span style="color: #666666">=</span><span style="color: #BA2121">&quot;triangle.js&quot;</span>&gt;&lt;/<span style="color: #008000; font-weight: bold">script</span>&gt;
 &lt;/<span style="color: #008000; font-weight: bold">body</span>&gt;
 &lt;/<span style="color: #008000; font-weight: bold">html</span>&gt;
 </pre></div>
@@ -50,18 +50,18 @@ a mobile-friendly page with a full-screen canvas.</p>
 <p>Go ahead and create <code>triangle.js</code> with the following content.</p>
 <div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #008000; font-weight: bold">class</span> App {
   <span style="color: #008000; font-weight: bold">constructor</span>() {
-    <span style="color: #408080; font-style: italic">// TODO: create entities</span>
+    <span style="color: #3D7B7B; font-style: italic">// TODO: create entities</span>
     <span style="color: #008000; font-weight: bold">this</span>.render <span style="color: #666666">=</span> <span style="color: #008000; font-weight: bold">this</span>.render.bind(<span style="color: #008000; font-weight: bold">this</span>);
     <span style="color: #008000; font-weight: bold">this</span>.resize <span style="color: #666666">=</span> <span style="color: #008000; font-weight: bold">this</span>.resize.bind(<span style="color: #008000; font-weight: bold">this</span>);
     <span style="color: #008000">window</span>.addEventListener(<span style="color: #BA2121">&#39;resize&#39;</span>, <span style="color: #008000; font-weight: bold">this</span>.resize);
     <span style="color: #008000">window</span>.requestAnimationFrame(<span style="color: #008000; font-weight: bold">this</span>.render);
   }
   render() {
-    <span style="color: #408080; font-style: italic">// TODO: render scene</span>
+    <span style="color: #3D7B7B; font-style: italic">// TODO: render scene</span>
     <span style="color: #008000">window</span>.requestAnimationFrame(<span style="color: #008000; font-weight: bold">this</span>.render);
   }
   resize() {
-    <span style="color: #408080; font-style: italic">// TODO: adjust viewport and canvas</span>
+    <span style="color: #3D7B7B; font-style: italic">// TODO: adjust viewport and canvas</span>
   }
 }
 
@@ -81,9 +81,9 @@ that define a PBR material. We'll learn more about material packages in the next
 <h2>Spawn a local server</h2>
 <p>Because of CORS restrictions, your web app cannot fetch the material package directly from the
 file system. One way around this is to create a temporary server using Python or node:</p>
-<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span>python3 -m http.server     <span style="color: #408080; font-style: italic"># Python 3</span>
-python -m SimpleHTTPServer <span style="color: #408080; font-style: italic"># Python 2.7</span>
-npx http-server -p <span style="color: #666666">8000</span>    <span style="color: #408080; font-style: italic"># nodejs</span>
+<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span>python3 -m http.server     <span style="color: #3D7B7B; font-style: italic"># Python 3</span>
+python -m SimpleHTTPServer <span style="color: #3D7B7B; font-style: italic"># Python 2.7</span>
+npx http-server -p <span style="color: #666666">8000</span>    <span style="color: #3D7B7B; font-style: italic"># nodejs</span>
 </pre></div>
 
 <p>To see if this works, navigate to <a href="http://localhost:8000">http://localhost:8000</a> and check if you
@@ -185,10 +185,10 @@ view.</p>
 <span style="color: #008000; font-weight: bold">this</span>.view.setCamera(<span style="color: #008000; font-weight: bold">this</span>.camera);
 <span style="color: #008000; font-weight: bold">this</span>.view.setScene(<span style="color: #008000; font-weight: bold">this</span>.scene);
 
-<span style="color: #408080; font-style: italic">// Set up a blue-green background:</span>
+<span style="color: #3D7B7B; font-style: italic">// Set up a blue-green background:</span>
 <span style="color: #008000; font-weight: bold">this</span>.renderer.setClearOptions({clearColor<span style="color: #666666">:</span> [<span style="color: #666666">0.0</span>, <span style="color: #666666">0.1</span>, <span style="color: #666666">0.2</span>, <span style="color: #666666">1.0</span>], clear<span style="color: #666666">:</span> <span style="color: #008000; font-weight: bold">true</span>});
 
-<span style="color: #408080; font-style: italic">// Adjust the initial viewport:</span>
+<span style="color: #3D7B7B; font-style: italic">// Adjust the initial viewport:</span>
 <span style="color: #008000; font-weight: bold">this</span>.resize();
 </pre></div>
 
@@ -198,14 +198,14 @@ However the canvas is still blank!</p>
 <p>Recall that our App class has a skeletal render method, which the browser calls every time it needs
 to repaint. Often this is 60 times a second.</p>
 <div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span>render() {
-    <span style="color: #408080; font-style: italic">// TODO: render scene</span>
+    <span style="color: #3D7B7B; font-style: italic">// TODO: render scene</span>
     <span style="color: #008000">window</span>.requestAnimationFrame(<span style="color: #008000; font-weight: bold">this</span>.render);
 }
 </pre></div>
 
 <p>Let's flesh this out by rotating the triangle and invoking the Filament renderer. Add the following
 code to the top of the render method.</p>
-<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #408080; font-style: italic">// Rotate the triangle.</span>
+<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #3D7B7B; font-style: italic">// Rotate the triangle.</span>
 <span style="color: #008000; font-weight: bold">const</span> radians <span style="color: #666666">=</span> <span style="color: #008000">Date</span>.now() <span style="color: #666666">/</span> <span style="color: #666666">1000</span>;
 <span style="color: #008000; font-weight: bold">const</span> transform <span style="color: #666666">=</span> mat4.fromRotation(mat4.create(), radians, [<span style="color: #666666">0</span>, <span style="color: #666666">0</span>, <span style="color: #666666">1</span>]);
 <span style="color: #008000; font-weight: bold">const</span> tcm <span style="color: #666666">=</span> <span style="color: #008000; font-weight: bold">this</span>.engine.getTransformManager();
@@ -213,7 +213,7 @@ code to the top of the render method.</p>
 tcm.setTransform(inst, transform);
 inst.<span style="color: #AA22FF; font-weight: bold">delete</span>();
 
-<span style="color: #408080; font-style: italic">// Render the frame.</span>
+<span style="color: #3D7B7B; font-style: italic">// Render the frame.</span>
 <span style="color: #008000; font-weight: bold">this</span>.renderer.render(<span style="color: #008000; font-weight: bold">this</span>.swapChain, <span style="color: #008000; font-weight: bold">this</span>.view);
 </pre></div>
 

filament/CMakeLists.txt

@@ -92,7 +92,6 @@ set(SRCS
         src/UniformBuffer.cpp
         src/VertexBuffer.cpp
         src/View.cpp
-        src/Viewport.cpp
         src/components/CameraManager.cpp
         src/components/LightManager.cpp
         src/components/RenderableManager.cpp
@@ -118,14 +117,14 @@ set(SRCS
         src/details/Texture.cpp
         src/details/VertexBuffer.cpp
         src/details/View.cpp
-        src/fg2/Blackboard.cpp
-        src/fg2/DependencyGraph.cpp
-        src/fg2/FrameGraph.cpp
-        src/fg2/FrameGraphPass.cpp
-        src/fg2/FrameGraphResources.cpp
-        src/fg2/FrameGraphTexture.cpp
-        src/fg2/PassNode.cpp
-        src/fg2/ResourceNode.cpp
+        src/fg/Blackboard.cpp
+        src/fg/DependencyGraph.cpp
+        src/fg/FrameGraph.cpp
+        src/fg/FrameGraphPass.cpp
+        src/fg/FrameGraphResources.cpp
+        src/fg/FrameGraphTexture.cpp
+        src/fg/PassNode.cpp
+        src/fg/ResourceNode.cpp
         src/fsr.cpp
 )
 
@@ -177,19 +176,19 @@ set(PRIVATE_HDRS
         src/details/Texture.h
         src/details/VertexBuffer.h
         src/details/View.h
-        src/fg2/Blackboard.h
-        src/fg2/FrameGraph.h
-        src/fg2/FrameGraphId.h
-        src/fg2/FrameGraphPass.h
-        src/fg2/FrameGraphRenderPass.h
-        src/fg2/FrameGraphResources.h
-        src/fg2/FrameGraphTexture.h
-        src/fg2/Resource.cpp
-        src/fg2/details/DependencyGraph.h
-        src/fg2/details/PassNode.h
-        src/fg2/details/Resource.h
-        src/fg2/details/ResourceNode.h
-        src/fg2/details/Utilities.h
+        src/fg/Blackboard.h
+        src/fg/FrameGraph.h
+        src/fg/FrameGraphId.h
+        src/fg/FrameGraphPass.h
+        src/fg/FrameGraphRenderPass.h
+        src/fg/FrameGraphResources.h
+        src/fg/FrameGraphTexture.h
+        src/fg/Resource.cpp
+        src/fg/details/DependencyGraph.h
+        src/fg/details/PassNode.h
+        src/fg/details/Resource.h
+        src/fg/details/ResourceNode.h
+        src/fg/details/Utilities.h
         src/fsr.h
         src/materials/fsr/ffx_a.h
         src/materials/fsr/ffx_fsr1.h

filament/backend/CMakeLists.txt

@@ -42,6 +42,7 @@ set(PRIVATE_HDRS
         include/private/backend/CircularBuffer.h
         include/private/backend/CommandBufferQueue.h
         include/private/backend/CommandStream.h
+        include/private/backend/Dispatcher.h
         include/private/backend/Driver.h
         include/private/backend/DriverApi.h
         include/private/backend/DriverAPI.inc
@@ -64,8 +65,6 @@ if (FILAMENT_SUPPORTS_OPENGL AND NOT FILAMENT_USE_EXTERNAL_GLES3 AND NOT FILAMEN
             src/opengl/gl_headers.h
             src/opengl/GLUtils.cpp
             src/opengl/GLUtils.h
-            src/opengl/OpenGLBlitter.cpp
-            src/opengl/OpenGLBlitter.h
             src/opengl/OpenGLContext.cpp
             src/opengl/OpenGLContext.h
             src/opengl/OpenGLDriver.cpp
@@ -74,8 +73,8 @@ if (FILAMENT_SUPPORTS_OPENGL AND NOT FILAMENT_USE_EXTERNAL_GLES3 AND NOT FILAMEN
             src/opengl/OpenGLProgram.cpp
             src/opengl/OpenGLProgram.h
             src/opengl/OpenGLPlatform.cpp
-            src/opengl/TimerQuery.cpp
-            src/opengl/TimerQuery.h
+            src/opengl/OpenGLTimerQuery.cpp
+            src/opengl/OpenGLTimerQuery.h
             include/private/backend/OpenGLPlatform.h
     )
     if (EGL)
@@ -88,7 +87,6 @@ if (FILAMENT_SUPPORTS_OPENGL AND NOT FILAMENT_USE_EXTERNAL_GLES3 AND NOT FILAMEN
     endif ()
     if (ANDROID)
         list(APPEND SRCS src/opengl/platforms/ExternalStreamManagerAndroid.cpp)
-        list(APPEND SRCS src/android/ExternalTextureManagerAndroid.cpp)
         list(APPEND SRCS src/opengl/platforms/PlatformEGLAndroid.cpp)
     elseif (IOS)
         list(APPEND SRCS src/opengl/platforms/PlatformCocoaTouchGL.mm)

filament/backend/include/backend/DriverEnums.h

@@ -33,7 +33,6 @@
 #include <stddef.h>
 #include <stdint.h>
 
-namespace filament {
 /**
  * Types and enums used by filament's driver.
  *
@@ -41,7 +40,7 @@ namespace filament {
  * internal redeclaration of these types.
  * For e.g. Use Texture::Sampler instead of filament::SamplerType.
  */
-namespace backend {
+namespace filament::backend {
 
 static constexpr uint64_t SWAP_CHAIN_CONFIG_TRANSPARENT = 0x1;
 static constexpr uint64_t SWAP_CHAIN_CONFIG_READABLE = 0x2;
@@ -142,9 +141,9 @@ struct Viewport {
     uint32_t width;     //!< width in pixels
     uint32_t height;    //!< height in pixels
     //! get the right coordinate in window space of the viewport
-    int32_t right() const noexcept { return left + width; }
+    int32_t right() const noexcept { return left + int32_t(width); }
     //! get the top coordinate in window space of the viewport
-    int32_t top() const noexcept { return bottom + height; }
+    int32_t top() const noexcept { return bottom + int32_t(height); }
 };
 
 /**
@@ -160,7 +159,7 @@ struct DepthRange {
  * @see Fence, Fence::wait()
  */
 enum class FenceStatus : int8_t {
-    ERROR = -1,                 //!< An error occured. The Fence condition is not satisfied.
+    ERROR = -1,                 //!< An error occurred. The Fence condition is not satisfied.
     CONDITION_SATISFIED = 0,    //!< The Fence condition is satisfied.
     TIMEOUT_EXPIRED = 1,        //!< wait()'s timeout expired. The Fence condition is not satisfied.
 };
@@ -169,7 +168,7 @@ enum class FenceStatus : int8_t {
  * Status codes for sync objects
  */
 enum class SyncStatus : int8_t {
-    ERROR = -1,          //!< An error occured. The Sync is not signaled.
+    ERROR = -1,          //!< An error occurred. The Sync is not signaled.
     SIGNALED = 0,        //!< The Sync is signaled.
     NOT_SIGNALED = 1,    //!< The Sync is not signaled yet
 };
@@ -789,7 +788,6 @@ enum class BlendFunction : uint8_t {
 //! Stream for external textures
 enum class StreamType {
     NATIVE,     //!< Not synchronized but copy-free. Good for video.
-    TEXTURE_ID, //!< Synchronized, but GL-only and incurs copies. Good for AR on devices before API 26.
     ACQUIRED,   //!< Synchronized, copy-free, and take a release callback. Good for AR but requires API 26+.
 };
 
@@ -998,8 +996,7 @@ enum class Workaround : uint16_t {
     ALLOW_READ_ONLY_ANCILLARY_FEEDBACK_LOOP
 };
 
-} // namespace backend
-} // namespace filament
+} // namespace filament::backend
 
 template<> struct utils::EnableBitMaskOperators<filament::backend::TargetBufferFlags>
         : public std::true_type {};

filament/backend/include/backend/Platform.h

@@ -80,7 +80,7 @@ public:
      *                    underlying platform is returned and \p backendHint is updated
      *                    accordingly. Can't be nullptr.
      *
-     * @return A pointer to the Plaform object.
+     * @return A pointer to the Platform object.
      *
      * @see destroy
      */

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

@@ -1,5 +1,3 @@
-#include <utility>
-
 /*
  * Copyright (C) 2018 The Android Open Source Project
  *
@@ -20,23 +18,19 @@
 #define TNT_FILAMENT_BACKEND_PRIVATE_COMMANDSTREAM_H
 
 #include "private/backend/CircularBuffer.h"
+#include "private/backend/Dispatcher.h"
+#include "private/backend/Program.h"
+#include "private/backend/SamplerGroup.h"
+#include "private/backend/Driver.h"
 
 #include <backend/BufferDescriptor.h>
+#include <backend/DriverEnums.h>
 #include <backend/Handle.h>
 #include <backend/PipelineState.h>
 #include <backend/PixelBufferDescriptor.h>
 #include <backend/PresentCallable.h>
 #include <backend/TargetBufferInfo.h>
 
-#include "private/backend/Program.h"
-#include "private/backend/SamplerGroup.h"
-
-// FIXME: we'd like to not need this header here.
-#include "private/backend/Driver.h"
-
-#include <backend/DriverEnums.h>
-
-
 #include <utils/compiler.h>
 #include <utils/ThreadUtils.h>
 
@@ -45,40 +39,14 @@
 #include <thread>
 #include <utility>
 
-#include <cassert>
-#include <cstddef>
-#include <cstdint>
+#include <assert.h>
+#include <stddef.h>
+#include <stdint.h>
 
-// Set to true to print every commands out on log.d. This requires RTTI and DEBUG
+// Set to true to print every command out on log.d. This requires RTTI and DEBUG
 #define DEBUG_COMMAND_STREAM false
 
-namespace filament {
-namespace backend {
-
-class Driver;
-class CommandBase;
-
-/*
- * Dispatcher is a data structure containing only function pointers.
- * Each function pointer targets code that unpacks the arguments to the driver's method and
- * calls it.
- *
- * Dispatcher's function pointers are populated during initialization and no CommandStream calls
- * can be made before that.
- *
- * When a command is inserted into the stream, the corresponding function pointer is copied
- * directly into CommandBase from Dispatcher.
- */
-class Dispatcher {
-public:
-    using Execute = void (*)(Driver& driver, CommandBase* self, intptr_t* next);
-#define DECL_DRIVER_API_SYNCHRONOUS(RetType, methodName, paramsDecl, params)
-#define DECL_DRIVER_API(methodName, paramsDecl, params)                     Execute methodName##_;
-#define DECL_DRIVER_API_RETURN(RetType, methodName, paramsDecl, params)     Execute methodName##_;
-#include "DriverAPI.inc"
-};
-
-// ------------------------------------------------------------------------------------------------
+namespace filament::backend {
 
 class CommandBase {
     static constexpr size_t FILAMENT_OBJECT_ALIGNMENT = alignof(std::max_align_t);
@@ -96,8 +64,10 @@ public:
 
     // executes this command and returns the next one
     inline CommandBase* execute(Driver& driver) {
-        // it is important to return the next command offset by output parameter instead
-        // of return value -- it allows the compiler to perform the tail call optimization.
+        // 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
+        // probably better to pay the cost at just one location.
         intptr_t next;
         mExecute(driver, this, &next);
         return reinterpret_cast<CommandBase*>(reinterpret_cast<intptr_t>(this) + next);
@@ -132,7 +102,7 @@ constexpr decltype(auto) apply(M&& m, D&& d, T&& t) {
 /*
  * CommandType<> is just a wrapper class to specialize on a pointer-to-member of Driver
  * (i.e. a method pointer to a method of Driver of a particular type -- but not the
- * method itself). We only do that so we can identify the parameters of that method.
+ * method itself). We only do that, so we can identify the parameters of that method.
  * We won't call through that pointer though.
  */
 template<typename... ARGS>
@@ -208,7 +178,7 @@ class NoopCommand : public CommandBase {
     }
 public:
     inline constexpr explicit NoopCommand(void* next) noexcept
-            : CommandBase(execute), mNext(size_t((char *)next - (char *)this)) { }
+            : CommandBase(execute), mNext(intptr_t((char *)next - (char *)this)) { }
 };
 
 // ------------------------------------------------------------------------------------------------
@@ -216,41 +186,34 @@ public:
 #if !defined(NDEBUG) || (FILAMENT_DEBUG_COMMANDS >= FILAMENT_DEBUG_COMMANDS_ENABLE)
     // For now, simply pass the method name down as a string and throw away the parameters.
     // This is good enough for certain debugging needs and we can improve this later.
-    #define DEBUG_COMMAND_BEGIN(methodName, sync, ...) mDriver->debugCommandBegin(this, sync, #methodName)
-    #define DEBUG_COMMAND_END(methodName, sync) mDriver->debugCommandEnd(this, sync, #methodName)
+    #define DEBUG_COMMAND_BEGIN(methodName, sync, ...) mDriver.debugCommandBegin(this, sync, #methodName)
+    #define DEBUG_COMMAND_END(methodName, sync) mDriver.debugCommandEnd(this, sync, #methodName)
 #else
     #define DEBUG_COMMAND_BEGIN(methodName, sync, ...)
     #define DEBUG_COMMAND_END(methodName, sync)
 #endif
 
 class CommandStream {
-    // Dispatcher could be a value (instead of pointer), which saves a load when writing commands
-    // at the expense of a larger CommandStream object (about ~400 bytes)
-    Dispatcher* mDispatcher = nullptr;
-    Driver* mDriver = nullptr;
-    CircularBuffer* UTILS_RESTRICT mCurrentBuffer = nullptr;
-
-#ifndef NDEBUG
-    // just for debugging...
-    std::thread::id mThreadId{};
-#endif
-
-    bool mUsePerformanceCounter = false;
-
     template<typename T>
     struct AutoExecute {
         T closure;
-        inline AutoExecute(T&& closure) : closure(std::forward<T>(closure)) {}
+        inline explicit AutoExecute(T&& closure) : closure(std::forward<T>(closure)) {}
         inline ~AutoExecute() { closure(); }
     };
 
+public:
+    CommandStream(Driver& driver, CircularBuffer& buffer) noexcept;
+
+    CommandStream(CommandStream const& rhs) noexcept = delete;
+    CommandStream& operator=(CommandStream const& rhs) noexcept = delete;
+
 public:
 #define DECL_DRIVER_API(methodName, paramsDecl, params)                                         \
     inline void methodName(paramsDecl) {                                                        \
         DEBUG_COMMAND_BEGIN(methodName, false, params);                                         \
         using Cmd = COMMAND_TYPE(methodName);                                                   \
         void* const p = allocateCommand(CommandBase::align(sizeof(Cmd)));                       \
-        new(p) Cmd(mDispatcher->methodName##_, APPLY(std::move, params));                       \
+        new(p) Cmd(mDispatcher.methodName##_, APPLY(std::move, params));                        \
         DEBUG_COMMAND_END(methodName, false);                                                   \
     }
 
@@ -260,16 +223,16 @@ public:
         AutoExecute callOnExit([=](){                                                           \
             DEBUG_COMMAND_END(methodName, true);                                                \
         });                                                                                     \
-        return apply(&Driver::methodName, *mDriver, std::forward_as_tuple(params));             \
+        return apply(&Driver::methodName, mDriver, std::forward_as_tuple(params));              \
     }
 
 #define DECL_DRIVER_API_RETURN(RetType, methodName, paramsDecl, params)                         \
     inline RetType methodName(paramsDecl) {                                                     \
         DEBUG_COMMAND_BEGIN(methodName, false, params);                                         \
-        RetType result = mDriver->methodName##S();                                              \
+        RetType result = mDriver.methodName##S();                                               \
         using Cmd = COMMAND_TYPE(methodName##R);                                                \
         void* const p = allocateCommand(CommandBase::align(sizeof(Cmd)));                       \
-        new(p) Cmd(mDispatcher->methodName##_, RetType(result), APPLY(std::move, params));      \
+        new(p) Cmd(mDispatcher.methodName##_, RetType(result), APPLY(std::move, params));       \
         DEBUG_COMMAND_END(methodName, false);                                                   \
         return result;                                                                          \
     }
@@ -277,10 +240,7 @@ public:
 #include "DriverAPI.inc"
 
 public:
-    CommandStream() noexcept = default;
-    CommandStream(Driver& driver, CircularBuffer& buffer) noexcept;
-
-    // This is for debugging only. Currently CircularBuffer can only be written from a
+    // 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.
     inline void debugThreading() noexcept {
@@ -315,8 +275,21 @@ public:
 private:
     inline void* allocateCommand(size_t size) {
         assert_invariant(utils::ThreadUtils::isThisThread(mThreadId));
-        return mCurrentBuffer->allocate(size);
+        return mCurrentBuffer.allocate(size);
     }
+
+    // We use a copy of Dispatcher (instead of a pointer) because this removes one dereference
+    // when executing driver commands.
+    Driver& UTILS_RESTRICT mDriver;
+    CircularBuffer& UTILS_RESTRICT mCurrentBuffer;
+    Dispatcher mDispatcher;
+
+#ifndef NDEBUG
+    // just for debugging...
+    std::thread::id mThreadId{};
+#endif
+
+    bool mUsePerformanceCounter = false;
 };
 
 void* CommandStream::allocate(size_t size, size_t alignment) noexcept {
@@ -341,7 +314,6 @@ PodType* CommandStream::allocatePod(size_t count, size_t alignment) noexcept {
     return static_cast<PodType*>(allocate(count * sizeof(PodType), alignment));
 }
 
-} // namespace backend
-} // namespace filament
+} // namespace filament::backend
 
 #endif // TNT_FILAMENT_BACKEND_PRIVATE_COMMANDSTREAM_H

filament/backend/include/private/backend/Dispatcher.h

@@ -0,0 +1,50 @@
+/*
+ * Copyright (C) 2022 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_PRIVATE_DISPATCHER_H
+#define TNT_FILAMENT_BACKEND_PRIVATE_DISPATCHER_H
+
+#include <stdint.h>
+
+namespace filament::backend {
+
+class Driver;
+class CommandBase;
+
+/*
+ * Dispatcher is a data structure containing only function pointers.
+ * Each function pointer targets code that unpacks the arguments to the driver's method and
+ * calls it.
+ *
+ * Dispatcher's function pointers are populated during initialization and no CommandStream calls
+ * can be made before that.
+ *
+ * When a command is inserted into the stream, the corresponding function pointer is copied
+ * directly into CommandBase from Dispatcher.
+ */
+class Dispatcher {
+public:
+    using Execute = void (*)(Driver& driver, CommandBase* self, intptr_t* next);
+#define DECL_DRIVER_API_SYNCHRONOUS(RetType, methodName, paramsDecl, params)
+#define DECL_DRIVER_API(methodName, paramsDecl, params)                     Execute methodName##_;
+#define DECL_DRIVER_API_RETURN(RetType, methodName, paramsDecl, params)     Execute methodName##_;
+
+#include "DriverAPI.inc"
+};
+
+} // namespace filament::backend
+
+#endif //TNT_FILAMENT_BACKEND_PRIVATE_DISPATCHER_H

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

@@ -17,23 +17,14 @@
 #ifndef TNT_FILAMENT_BACKEND_PRIVATE_DRIVER_H
 #define TNT_FILAMENT_BACKEND_PRIVATE_DRIVER_H
 
-#include <backend/BufferDescriptor.h>
-#include <backend/CallbackHandler.h>
 #include <backend/DriverEnums.h>
 #include <backend/Handle.h>
 #include <backend/PipelineState.h>
-#include <backend/PixelBufferDescriptor.h>
-#include <backend/PresentCallable.h>
 #include <backend/TargetBufferInfo.h>
 
 #include "private/backend/DriverApiForward.h"
-#include "private/backend/Program.h"
-#include "private/backend/SamplerGroup.h"
 
 #include <utils/compiler.h>
-#include <utils/Log.h>
-
-#include <functional>
 
 #include <stdint.h>
 
@@ -49,8 +40,13 @@
 
 #define FILAMENT_DEBUG_COMMANDS              FILAMENT_DEBUG_COMMANDS_NONE
 
-namespace filament {
-namespace backend {
+namespace filament::backend {
+
+class BufferDescriptor;
+class CallbackHandler;
+class PixelBufferDescriptor;
+class Program;
+class SamplerGroup;
 
 template<typename T>
 class ConcreteDispatcher;
@@ -59,27 +55,32 @@ class CommandStream;
 
 class Driver {
 public:
-    static size_t getElementTypeSize(ElementType type) noexcept;
-
     virtual ~Driver() noexcept;
 
+    static size_t getElementTypeSize(ElementType type) noexcept;
+
     // called from the main thread (NOT the render-thread) at various intervals, this
     // is where the driver can execute user callbacks.
     virtual void purge() noexcept = 0;
 
     virtual ShaderModel getShaderModel() const noexcept = 0;
 
-    virtual Dispatcher& getDispatcher() noexcept = 0;
+    // Returns the dispatcher. This is only called once during initialization of the CommandStream,
+    // so it doesn't matter that it's virtual.
+    virtual Dispatcher getDispatcher() const noexcept = 0;
 
     // called from CommandStream::execute on the render-thread
     // the fn function will execute a batch of driver commands
     // this gives the driver a chance to wrap their execution in a meaningful manner
     // the default implementation simply calls fn
-    virtual void execute(std::function<void(void)> fn) noexcept;
+    virtual void execute(std::function<void(void)> const& fn) noexcept;
 
     // This is called on debug build, or when enabled manually on the backend thread side.
-    virtual void debugCommandBegin(CommandStream* cmds, bool synchronous, const char* methodName) noexcept = 0;
-    virtual void debugCommandEnd(CommandStream* cmds, bool synchronous, const char* methodName) noexcept = 0;
+    virtual void debugCommandBegin(CommandStream* cmds,
+            bool synchronous, const char* methodName) noexcept = 0;
+
+    virtual void debugCommandEnd(CommandStream* cmds,
+            bool synchronous, const char* methodName) noexcept = 0;
 
     /*
      * Asynchronous calls here only to provide a type to CommandStream. They must be non-virtual
@@ -101,7 +102,6 @@ public:
 #include "private/backend/DriverAPI.inc"
 };
 
-} // namespace backend
-} // namespace filament
+} // namespace filament::backend
 
 #endif // TNT_FILAMENT_BACKEND_PRIVATE_DRIVER_H

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

@@ -246,11 +246,6 @@ DECL_DRIVER_API_R_N(backend::SwapChainHandle, createSwapChainHeadless,
         uint32_t, height,
         uint64_t, flags)
 
-DECL_DRIVER_API_R_N(backend::StreamHandle, createStreamFromTextureId,
-        intptr_t, externalTextureId,
-        uint32_t, width,
-        uint32_t, height)
-
 DECL_DRIVER_API_R_0(backend::TimerQueryHandle, createTimerQuery)
 
 
@@ -461,14 +456,6 @@ DECL_DRIVER_API_N(readPixels,
         uint32_t, height,
         backend::PixelBufferDescriptor&&, data)
 
-DECL_DRIVER_API_N(readStreamPixels,
-        backend::StreamHandle, sh,
-        uint32_t, x,
-        uint32_t, y,
-        uint32_t, width,
-        uint32_t, height,
-        backend::PixelBufferDescriptor&&, data)
-
 /*
  * Rendering operations
  * --------------------

filament/backend/include/private/backend/DriverApiForward.h

@@ -17,15 +17,12 @@
 #ifndef TNT_FILAMENT_BACKEND_PRIVATE_DRIVERAPIFORWARD_H
 #define TNT_FILAMENT_BACKEND_PRIVATE_DRIVERAPIFORWARD_H
 
-
-namespace filament {
-namespace backend {
+namespace filament::backend {
 
 class CommandStream;
 
 using DriverApi = CommandStream;
 
-} // namespace backend
-} // namespace filament
+} // namespace filament::backend
 
 #endif // TNT_FILAMENT_BACKEND_PRIVATE_DRIVERAPIFORWARD_H

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

@@ -61,7 +61,7 @@ public:
      */
     template<typename D, typename ... ARGS>
     Handle<D> allocateAndConstruct(ARGS&& ... args) noexcept {
-        Handle<D> h{ allocateHandle(sizeof(D)) };
+        Handle<D> h{ allocateHandle<sizeof(D)>() };
         D* addr = handle_cast<D*>(h);
         new(addr) D(std::forward<ARGS>(args)...);
 #if HANDLE_TYPE_SAFETY
@@ -84,7 +84,7 @@ public:
      */
     template<typename D>
     Handle<D> allocate() noexcept {
-        Handle<D> h{ allocateHandle(sizeof(D)) };
+        Handle<D> h{ allocateHandle<sizeof(D)>() };
 #if HANDLE_TYPE_SAFETY
         D* addr = handle_cast<D*>(h);
         mLock.lock();
@@ -167,7 +167,7 @@ public:
             }
 #endif
             p->~D();
-            deallocateHandle(handle.getId(), sizeof(D));
+            deallocateHandle<sizeof(D)>(handle.getId());
         }
     }
 
@@ -249,23 +249,49 @@ private:
             utils::LockingPolicy::SpinLock>;
 #endif
 
-    // this is inlined because we're always called with a constexpr size
-    HandleBase::HandleId allocateHandle(size_t size) noexcept {
-        void* p = mHandleArena.alloc(size);
-        if (UTILS_LIKELY(p)) {
-            return pointerToHandle(p);
+    // allocateHandle()/deallocateHandle() selects the pool to use at compile-time based on the
+    // allocation size this is always inlined, because all these do is to call
+    // allocateHandleInPool()/deallocateHandleFromPool() with the right pool size.
+    template<size_t SIZE>
+    HandleBase::HandleId allocateHandle() noexcept {
+        if constexpr (SIZE <= P0) { return allocateHandleInPool<P0>(); }
+        if constexpr (SIZE <= P1) { return allocateHandleInPool<P1>(); }
+        return allocateHandleInPool<P2>();
+    }
+
+    template<size_t SIZE>
+    void deallocateHandle(HandleBase::HandleId id) noexcept {
+        if constexpr (SIZE <= P0) {
+            deallocateHandleFromPool<P0>(id);
+        } else if constexpr (SIZE <= P1) {
+            deallocateHandleFromPool<P1>(id);
         } else {
-            return allocateHandleSlow(size);
+            deallocateHandleFromPool<P2>(id);
         }
     }
 
-    // this is inlined because we're always called with a constexpr size
-    void deallocateHandle(HandleBase::HandleId id, size_t size) noexcept {
+    // allocateHandleInPool()/deallocateHandleFromPool() is NOT inlined, which will cause three
+    // versions to be generated, one for each pool. Because the arena is synchronized,
+    // the code generated is not trivial (even if it's not insane either).
+    template<size_t SIZE>
+    UTILS_NOINLINE
+    HandleBase::HandleId allocateHandleInPool() noexcept {
+        void* p = mHandleArena.alloc(SIZE);
+        if (UTILS_LIKELY(p)) {
+            return pointerToHandle(p);
+        } else {
+            return allocateHandleSlow(SIZE);
+        }
+    }
+
+    template<size_t SIZE>
+    UTILS_NOINLINE
+    void deallocateHandleFromPool(HandleBase::HandleId id) noexcept {
         if (UTILS_LIKELY(isPoolHandle(id))) {
             void* p = handleToPointer(id);
-            mHandleArena.free(p, size);
+            mHandleArena.free(p, SIZE);
         } else {
-            deallocateHandleSlow(id, size);
+            deallocateHandleSlow(id, SIZE);
         }
     }
 

filament/backend/include/private/backend/OpenGLPlatform.h

@@ -82,15 +82,6 @@ public:
     virtual void detach(Stream* stream) noexcept = 0;
     virtual void updateTexImage(Stream* stream, int64_t* timestamp) noexcept = 0;
 
-    // external texture storage
-    virtual ExternalTexture* createExternalTextureStorage() noexcept = 0;
-
-    // this is called synchronously in the application thread (NOT the Driver thread)
-    virtual void reallocateExternalStorage(ExternalTexture* ets,
-            uint32_t w, uint32_t h, TextureFormat format) noexcept = 0;
-
-    virtual void destroyExternalTextureStorage(ExternalTexture* ets) noexcept = 0;
-
     // The method allows platforms to convert a user-supplied external image object into a new type
     // (e.g. HardwareBuffer => EGLImage). It makes sense for the default implementation to do nothing.
     virtual AcquiredImage transformAcquiredImage(AcquiredImage source) noexcept { return source; }

filament/backend/src/CircularBuffer.cpp

@@ -33,8 +33,7 @@
 
 using namespace utils;
 
-namespace filament {
-namespace backend {
+namespace filament::backend {
 
 CircularBuffer::CircularBuffer(size_t size) {
     mData = alloc(size);
@@ -56,6 +55,7 @@ CircularBuffer::~CircularBuffer() noexcept {
 // If the system does not support mmap, emulate soft circular buffer with two buffers next
 // to each others and a special case in circularize()
 
+UTILS_NOINLINE
 void* CircularBuffer::alloc(size_t size) noexcept {
 #if HAS_MMAP
     void* data = nullptr;
@@ -127,6 +127,7 @@ void* CircularBuffer::alloc(size_t size) noexcept {
 #endif
 }
 
+UTILS_NOINLINE
 void CircularBuffer::dealloc() noexcept {
 #if HAS_MMAP
     if (mData) {
@@ -162,5 +163,4 @@ void CircularBuffer::circularize() noexcept {
     mTail = mHead;
 }
 
-} // namespace backend
-} // namespace filament
+} // namespace filament::backend

filament/backend/src/CommandStream.cpp

@@ -29,8 +29,7 @@
 
 using namespace utils;
 
-namespace filament {
-namespace backend {
+namespace filament::backend {
 
 // ------------------------------------------------------------------------------------------------
 // A few utility functions for debugging...
@@ -57,9 +56,9 @@ static UTILS_NOINLINE UTILS_UNUSED std::string extractMethodName(std::string& co
 // ------------------------------------------------------------------------------------------------
 
 CommandStream::CommandStream(Driver& driver, CircularBuffer& buffer) noexcept
-        : mDispatcher(&driver.getDispatcher()),
-          mDriver(&driver),
-          mCurrentBuffer(&buffer)
+        : mDriver(driver),
+          mCurrentBuffer(buffer),
+          mDispatcher(driver.getDispatcher())
 #ifndef NDEBUG
           , mThreadId(ThreadUtils::getThreadId())
 #endif
@@ -84,8 +83,8 @@ void CommandStream::execute(void* buffer) {
         }
     }
 
-    mDriver->execute([this, buffer]() {
-        Driver& UTILS_RESTRICT driver = *mDriver;
+    mDriver.execute([this, buffer]() {
+        Driver& UTILS_RESTRICT driver = mDriver;
         CommandBase* UTILS_RESTRICT base = static_cast<CommandBase*>(buffer);
         while (UTILS_LIKELY(base)) {
             base = base->execute(driver);
@@ -152,5 +151,4 @@ void CustomCommand::execute(Driver&, CommandBase* base, intptr_t* next) noexcept
     static_cast<CustomCommand*>(base)->~CustomCommand();
 }
 
-} // namespace backend
-} // namespace filament
+} // namespace filament::backend

filament/backend/src/CommandStreamDispatcher.h

@@ -23,9 +23,9 @@
 #include <utils/compiler.h>
 #include <utils/Systrace.h>
 
-#include <cstddef>
 #include <utility>
 
+#include <stddef.h>
 #include <stdint.h>
 
 #define DEBUG_LEVEL_NONE       0
@@ -46,10 +46,10 @@
 namespace filament::backend {
 
 template<typename ConcreteDriver>
-class ConcreteDispatcher final : public Dispatcher {
+class ConcreteDispatcher {
 public:
-    // initialize the dispatch table
-    ConcreteDispatcher() noexcept;
+
+    static Dispatcher make() noexcept;
 
 private:
 #define DECL_DRIVER_API_SYNCHRONOUS(RetType, methodName, paramsDecl, params)
@@ -72,13 +72,19 @@ private:
 
 template<typename ConcreteDriver>
 UTILS_NOINLINE
-ConcreteDispatcher<ConcreteDriver>::ConcreteDispatcher() noexcept : Dispatcher() {
-#define DECL_DRIVER_API_SYNCHRONOUS(RetType, methodName, paramsDecl, params)
-#define DECL_DRIVER_API(methodName, paramsDecl, params)                 methodName##_ = &ConcreteDispatcher::methodName;
-#define DECL_DRIVER_API_RETURN(RetType, methodName, paramsDecl, params) methodName##_ = &ConcreteDispatcher::methodName;
-#include "private/backend/DriverAPI.inc"
-}
+Dispatcher ConcreteDispatcher<ConcreteDriver>::make() noexcept {
+    Dispatcher dispatcher;
 
+#define DECL_DRIVER_API_SYNCHRONOUS(RetType, methodName, paramsDecl, params)
+#define DECL_DRIVER_API(methodName, paramsDecl, params)                 \
+                dispatcher.methodName##_ = &ConcreteDispatcher::methodName;
+#define DECL_DRIVER_API_RETURN(RetType, methodName, paramsDecl, params) \
+                dispatcher.methodName##_ = &ConcreteDispatcher::methodName;
+
+#include "private/backend/DriverAPI.inc"
+
+    return dispatcher;
+}
 
 } // namespace filament::backend
 

filament/backend/src/Driver.cpp

@@ -15,6 +15,8 @@
  */
 
 #include "private/backend/Driver.h"
+
+#include "private/backend/AcquiredImage.h"
 #include "private/backend/CommandStream.h"
 
 #include "DriverBase.h"
@@ -25,20 +27,15 @@
 #include <math/vec4.h>
 
 #include <backend/BufferDescriptor.h>
-#include <backend/PixelBufferDescriptor.h>
 
 #include <utils/Systrace.h>
 
 using namespace utils;
+using namespace filament::math;
 
-namespace filament {
+namespace filament::backend {
 
-using namespace math;
-
-namespace backend {
-
-DriverBase::DriverBase(Dispatcher* dispatcher) noexcept
-        : mDispatcher(dispatcher) {
+DriverBase::DriverBase() noexcept {
     if constexpr (UTILS_HAS_THREADING) {
         // This thread services user callbacks
         mServiceThread = std::thread([this]() {
@@ -75,7 +72,6 @@ DriverBase::~DriverBase() noexcept {
         lock.unlock();
         mServiceThread.join();
     }
-    delete mDispatcher;
 }
 
 // ------------------------------------------------------------------------------------------------
@@ -169,14 +165,6 @@ void DriverBase::debugCommandEnd(CommandStream* cmds, bool synchronous, const ch
     }
 }
 
-// ------------------------------------------------------------------------------------------------
-
-Driver::~Driver() noexcept = default;
-
-void Driver::execute(std::function<void(void)> fn) noexcept {
-    fn();
-}
-
 size_t Driver::getElementTypeSize(ElementType type) noexcept {
     switch (type) {
         case ElementType::BYTE:     return sizeof(int8_t);
@@ -208,5 +196,12 @@ size_t Driver::getElementTypeSize(ElementType type) noexcept {
     }
 }
 
-} // namespace backend
-} // namespace filament
+// ------------------------------------------------------------------------------------------------
+
+Driver::~Driver() noexcept = default;
+
+void Driver::execute(std::function<void(void)> const& fn) noexcept {
+    fn();
+}
+
+} // namespace filament::backend

filament/backend/src/DriverBase.h

@@ -22,14 +22,14 @@
 
 #include <backend/Platform.h>
 
+#include <backend/BufferDescriptor.h>
 #include <backend/DriverEnums.h>
 #include <backend/CallbackHandler.h>
 
-#include "private/backend/AcquiredImage.h"
+#include "private/backend/Dispatcher.h"
 #include "private/backend/Driver.h"
 #include "private/backend/SamplerGroup.h"
 
-#include <array>
 #include <condition_variable>
 #include <memory>
 #include <mutex>
@@ -41,7 +41,7 @@
 
 namespace filament::backend {
 
-class Dispatcher;
+struct AcquiredImage;
 
 /*
  * Hardware handles
@@ -72,7 +72,7 @@ struct HwBufferObject : public HwBase {
     uint32_t byteCount{};
 
     HwBufferObject() noexcept = default;
-    HwBufferObject(uint32_t byteCount) noexcept : byteCount(byteCount) {}
+    explicit HwBufferObject(uint32_t byteCount) noexcept : byteCount(byteCount) {}
 };
 
 struct HwIndexBuffer : public HwBase {
@@ -167,21 +167,16 @@ struct HwTimerQuery : public HwBase {
 
 class DriverBase : public Driver {
 public:
-    DriverBase() = delete;
-    explicit DriverBase(Dispatcher* dispatcher) noexcept;
+    DriverBase() noexcept;
     ~DriverBase() noexcept override;
 
     void purge() noexcept final;
 
-    Dispatcher& getDispatcher() noexcept final { return *mDispatcher; }
-
     // --------------------------------------------------------------------------------------------
     // Privates
     // --------------------------------------------------------------------------------------------
 
 protected:
-    Dispatcher* mDispatcher;
-
     class CallbackDataDetails;
 
     // Helpers...

filament/backend/src/Handle.cpp

@@ -28,7 +28,7 @@ namespace filament::backend {
 
 #ifndef NDEBUG
 
-static char const * const kOurNamespace = "filament::";
+static char const * const kOurNamespace = "filament::backend";
 
 // removes all occurrences of "what" from "str"
 UTILS_NOINLINE

filament/backend/src/android/ExternalTextureManagerAndroid.cpp

@@ -1,223 +0,0 @@
-/*
- * Copyright (C) 2018 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 "ExternalTextureManagerAndroid.h"
-
-#include <utils/api_level.h>
-#include <utils/compiler.h>
-#include <utils/Log.h>
-
-#include <dlfcn.h>
-
-using namespace utils;
-
-namespace filament {
-using namespace backend;
-
-template <typename T>
-static void loadSymbol(T*& pfn, const char *symbol) noexcept {
-    pfn = (T*)dlsym(RTLD_DEFAULT, symbol);
-}
-
-// ------------------------------------------------------------------------------------------------
-
-namespace ndk {
-/*
- * This mimics the GraphicBuffer class for pre-API 26
- */
-template<typename NATIVE_TYPE, typename REF>
-struct ANativeObjectBase : public NATIVE_TYPE, public REF {
-};
-
-struct android_native_base_t {
-    unsigned int magic;
-    unsigned int version;
-    void* reserved[4];
-    void (* incRef)(struct android_native_base_t* base);
-    void (* decRef)(struct android_native_base_t* base);
-};
-
-struct ANativeWindowBuffer {
-    struct android_native_base_t common;
-    unsigned int width;
-    unsigned int height;
-    unsigned int stride;
-    unsigned int format;
-    unsigned int usage_deprecated;
-    uintptr_t layerCount;
-    void* reserved[1];
-    const void* handle;
-    uint64_t usage;
-    void* reserved_proc[8 - (sizeof(uint64_t) / sizeof(void*))];
-};
-
-struct RefBase {
-    virtual ~RefBase() = default;
-    void* ref;
-};
-
-struct GraphicBuffer : public ANativeObjectBase<ANativeWindowBuffer, RefBase> {
-};
-struct GraphicBufferWrapper {
-    GraphicBuffer* graphicBuffer;
-};
-} // namespace ndk
-
-// ------------------------------------------------------------------------------------------------
-using namespace ndk;
-
-struct EGLExternalTexture : public ExternalTextureManagerAndroid::ExternalTexture {
-    GraphicBufferWrapper* graphicBufferWrapper = nullptr;
-};
-
-ExternalTextureManagerAndroid& ExternalTextureManagerAndroid::create() noexcept {
-    return *(new ExternalTextureManagerAndroid{});
-}
-
-void ExternalTextureManagerAndroid::destroy(ExternalTextureManagerAndroid* pExternalTextureManager) noexcept {
-    delete pExternalTextureManager;
-}
-
-// called on gl thread
-ExternalTextureManagerAndroid::ExternalTextureManagerAndroid() noexcept
-        : mVm(VirtualMachineEnv::get()) {
-}
-
-// not quite sure on which thread this is going to be called
-ExternalTextureManagerAndroid::~ExternalTextureManagerAndroid() noexcept {
-    if (__builtin_available(android 26, *)) {
-    } else {
-        if (mGraphicBufferClass) {
-            JNIEnv* env = VirtualMachineEnv::getThreadEnvironment();
-            if (env) {
-                env->DeleteGlobalRef(mGraphicBufferClass);
-            }
-        }
-    }
-}
-
-// called on gl thread
-backend::Platform::ExternalTexture* ExternalTextureManagerAndroid::createExternalTexture() noexcept {
-    if (__builtin_available(android 26, *)) {
-    } else {
-        // initialize java stuff on-demand
-        if (!mGraphicBufferClass) {
-            JNIEnv* env = mVm.getEnvironment();
-            mGraphicBufferClass = env->FindClass("android/view/GraphicBuffer");
-            mGraphicBuffer_nCreateGraphicBuffer = env->GetStaticMethodID(
-                    mGraphicBufferClass, "nCreateGraphicBuffer", "(IIII)J");
-            mGraphicBuffer_nDestroyGraphicBuffer = env->GetStaticMethodID(
-                    mGraphicBufferClass, "nDestroyGraphicBuffer", "(J)V");
-
-            mGraphicBufferClass = static_cast<jclass>(env->NewGlobalRef(mGraphicBufferClass));
-        }
-    }
-    EGLExternalTexture* ets = new EGLExternalTexture;
-    return ets;
-}
-
-// called on app thread
-void ExternalTextureManagerAndroid::reallocate(
-        backend::Platform::ExternalTexture* ets, uint32_t w, uint32_t h,
-        backend::TextureFormat format, uint64_t usage) noexcept {
-    destroyStorage(ets);
-    alloc(ets, w, h, format, usage);
-}
-
-// called on gl thread
-void ExternalTextureManagerAndroid::destroy(backend::Platform::ExternalTexture* ets) noexcept {
-    destroyStorage(ets);
-    delete static_cast<EGLExternalTexture*>(ets);
-}
-
-// called on app thread
-void ExternalTextureManagerAndroid::alloc(
-        backend::Platform::ExternalTexture* t,
-        uint32_t w, uint32_t h, TextureFormat format, uint64_t usage) noexcept {
-
-    EGLExternalTexture* ets = static_cast<EGLExternalTexture*>(t);
-
-    AHardwareBuffer_Desc desc = { w, h, 1, 0, usage, 0, 0, 0 };
-    switch (format) {
-        case TextureFormat::RGB8:
-            // don't use R8G8B8 here because some drivers produce garbled images
-            desc.format = AHARDWAREBUFFER_FORMAT_R8G8B8X8_UNORM;
-            break;
-        case TextureFormat::RGBA8:
-            desc.format = AHARDWAREBUFFER_FORMAT_R8G8B8A8_UNORM;
-            break;
-        case TextureFormat::RGB565:
-            desc.format = AHARDWAREBUFFER_FORMAT_R5G6B5_UNORM;
-            break;
-        case TextureFormat::RGB10_A2:
-            desc.format = AHARDWAREBUFFER_FORMAT_R10G10B10A2_UNORM;
-            break;
-        default:
-            slog.e << "Unsupported format " << (int)format << ", use RGBA8 or RGB8 only."
-                   << io::endl;
-            return;
-    }
-
-    if (__builtin_available(android 26, *)) {
-        // allocate new storage...
-        AHardwareBuffer* buffer = nullptr;
-        if (AHardwareBuffer_allocate(&desc, &buffer) < 0) {
-            slog.e << "AHardwareBuffer_allocate() failed" << io::endl;
-            return;
-        }
-        ets->hardwareBuffer = buffer;
-    } else {
-        // note: This is called on the application thread (not the GL thread)
-        JNIEnv* env = VirtualMachineEnv::getThreadEnvironment();
-        if (!env) {
-            return; // this should not happen
-        }
-
-        jlong graphicBufferWrapperJni = env->CallStaticLongMethod(mGraphicBufferClass,
-                mGraphicBuffer_nCreateGraphicBuffer, w, h, desc.format, usage);
-        VirtualMachineEnv::handleException(env);
-
-        if (graphicBufferWrapperJni) {
-            GraphicBuffer* const gb = ((GraphicBufferWrapper*)graphicBufferWrapperJni)->graphicBuffer;
-            ets->graphicBufferWrapper = (GraphicBufferWrapper*)graphicBufferWrapperJni;
-            ets->clientBuffer = static_cast<ANativeWindowBuffer*>(gb);
-        }
-    }
-}
-
-// called on gl thread
-void ExternalTextureManagerAndroid::destroyStorage(backend::Platform::ExternalTexture* t) noexcept {
-        EGLExternalTexture* ets = static_cast<EGLExternalTexture*>(t);
-    if (__builtin_available(android 26, *)) {
-        // destroy the current storage if any
-        if (ets->hardwareBuffer) {
-            AHardwareBuffer_release(ets->hardwareBuffer);
-            ets->hardwareBuffer = nullptr;
-        }
-    } else {
-        if (ets->graphicBufferWrapper) {
-            JNIEnv* env = VirtualMachineEnv::get().getEnvironment();
-            env->CallStaticVoidMethod(mGraphicBufferClass,
-                    mGraphicBuffer_nDestroyGraphicBuffer, (jlong)ets->graphicBufferWrapper);
-            VirtualMachineEnv::handleException(env);
-            ets->graphicBufferWrapper = nullptr;
-        }
-    }
-}
-
-} // namespace filament
-

filament/backend/src/android/ExternalTextureManagerAndroid.h

@@ -1,86 +0,0 @@
-/*
- * Copyright (C) 2018 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_DRIVER_ANDROID_EXTERNAL_TEXTURE_MANAGER_ANDROID_H
-#define TNT_FILAMENT_DRIVER_ANDROID_EXTERNAL_TEXTURE_MANAGER_ANDROID_H
-
-#include "private/backend/VirtualMachineEnv.h"
-
-#include <backend/DriverEnums.h>
-#include <backend/Platform.h>
-
-#include <android/api-level.h>
-#include <android/hardware_buffer.h>
-
-namespace filament {
-
-/*
- * ExternalTextureManagerAndroid::ExternalTexture is basically a wrapper for AHardwareBuffer.
- *
- * This class doesn't rely on GL or EGL, and could be used for other Android platform if needed
- * (e.g. Vulkan).
- *
- * ExternalTextureManagerAndroid handle allocation/destruction using either Java or the NDK,
- * whichever is available.
- */
-class ExternalTextureManagerAndroid {
-public:
-
-    struct ExternalTexture : public backend::Platform::ExternalTexture {
-        void* clientBuffer = nullptr;
-        AHardwareBuffer* hardwareBuffer = nullptr;
-    };
-
-    // must be called on backend thread
-    static ExternalTextureManagerAndroid& create() noexcept;
-
-    // must be called on backend thread
-    static void destroy(ExternalTextureManagerAndroid* pExternalTextureManager) noexcept;
-
-    // must be called on backend thread (only because we don't synchronize
-    backend::Platform::ExternalTexture* createExternalTexture() noexcept;
-
-    // called on app thread
-    void reallocate(
-        backend::Platform::ExternalTexture* ets, uint32_t w, uint32_t h,
-        backend::TextureFormat format, uint64_t usage) noexcept;
-
-    // must be called on backend thread
-    void destroy(backend::Platform::ExternalTexture* ets) noexcept;
-
-private:
-    ExternalTextureManagerAndroid() noexcept;
-    ~ExternalTextureManagerAndroid() noexcept;
-
-    // called on app thread
-    void alloc(backend::Platform::ExternalTexture* ets,
-               uint32_t w, uint32_t h, backend::TextureFormat format, uint64_t usage) noexcept;
-
-    // called on gl thread
-    void destroyStorage(backend::Platform::ExternalTexture* ets) noexcept;
-
-    VirtualMachineEnv& mVm;
-
-    jclass mGraphicBufferClass = nullptr;
-    jmethodID mGraphicBuffer_nCreateGraphicBuffer = nullptr;
-    jmethodID mGraphicBuffer_nDestroyGraphicBuffer = nullptr;
-};
-
-
-
-} // namespace filament
-
-#endif // TNT_FILAMENT_DRIVER_ANDROID_EXTERNAL_TEXTURE_MANAGER_ANDROID_H

filament/backend/src/metal/MetalBlitter.h

@@ -26,7 +26,6 @@
 
 namespace filament {
 namespace backend {
-namespace metal {
 
 struct MetalContext;
 
@@ -133,7 +132,6 @@ private:
 
 };
 
-} // namespace metal
 } // namespace backend
 } // namespace filament
 

filament/backend/src/metal/MetalBlitter.mm

@@ -23,7 +23,6 @@
 
 namespace filament {
 namespace backend {
-namespace metal {
 
 static const char* functionLibrary = R"(
 #include <metal_stdlib>
@@ -300,7 +299,7 @@ void MetalBlitter::blitDepthPlane(id<MTLCommandBuffer> cmdBuffer, bool blitColor
     }
     id<MTLFunction> fragmentFunction = getBlitFragmentFunction(key);
 
-    PipelineState pipelineState {
+    MetalPipelineState pipelineState {
         .vertexFunction = getBlitVertexFunction(),
         .fragmentFunction = fragmentFunction,
         .vertexDescription = {},
@@ -530,6 +529,5 @@ id<MTLFunction> MetalBlitter::getBlitFragmentFunction(BlitFunctionKey key) {
     return function;
 }
 
-} // namespace metal
 } // namespace backend
 } // namespace filament

filament/backend/src/metal/MetalBuffer.h

@@ -26,7 +26,6 @@
 
 namespace filament {
 namespace backend {
-namespace metal {
 
 class MetalBuffer {
 public:
@@ -94,7 +93,6 @@ private:
     void copyIntoStreamBuffer(void* src, size_t size);
 };
 
-} // namespace metal
 } // namespace backend
 } // namespace filament
 

filament/backend/src/metal/MetalBuffer.mm

@@ -22,7 +22,6 @@
 
 namespace filament {
 namespace backend {
-namespace metal {
 
 MetalBuffer::MetalBuffer(MetalContext& context, BufferUsage usage, size_t size, bool forceGpuBuffer)
         : mBufferSize(size), mContext(context) {
@@ -206,6 +205,5 @@ void MetalBuffer::bindBuffers(id<MTLCommandBuffer> cmdBuffer, id<MTLRenderComman
     }
 }
 
-} // namespace metal
 } // namespace backend
 } // namespace filament

filament/backend/src/metal/MetalBufferPool.h

@@ -25,7 +25,6 @@
 
 namespace filament {
 namespace backend {
-namespace metal {
 
 struct MetalContext;
 
@@ -78,7 +77,6 @@ private:
     static constexpr uint32_t TIME_BEFORE_EVICTION = 10;
 };
 
-} // namespace metal
 } // namespace backend
 } // namespace filament
 

filament/backend/src/metal/MetalBufferPool.mm

@@ -26,7 +26,6 @@
 
 namespace filament {
 namespace backend {
-namespace metal {
 
 MetalBufferPoolEntry const* MetalBufferPool::acquireBuffer(size_t numBytes) {
     std::lock_guard<std::mutex> lock(mMutex);
@@ -110,6 +109,5 @@ void MetalBufferPool::reset() noexcept {
     mFreeStages.clear();
 }
 
-} // namespace metal
 } // namespace backend
 } // namespace filament

filament/backend/src/metal/MetalContext.h

@@ -36,14 +36,13 @@
 
 namespace filament {
 namespace backend {
-namespace metal {
 
 class MetalDriver;
 class MetalBlitter;
 class MetalBufferPool;
 class MetalRenderTarget;
 class MetalSwapChain;
-class TimerQueryInterface;
+class MetalTimerQueryInterface;
 struct MetalUniformBuffer;
 struct MetalIndexBuffer;
 struct MetalSamplerGroup;
@@ -113,7 +112,7 @@ struct MetalContext {
     MTLSharedEventListener* eventListener = nil;
     uint64_t signalId = 1;
 
-    TimerQueryInterface* timerQueryImpl;
+    MetalTimerQueryInterface* timerQueryImpl;
 
     std::stack<const char*> groupMarkers;
 
@@ -134,7 +133,6 @@ id<MTLTexture> getOrCreateEmptyTexture(MetalContext* context);
 
 bool isInRenderPass(MetalContext* context);
 
-} // namespace metal
 } // namespace backend
 } // namespace filament
 

filament/backend/src/metal/MetalContext.mm

@@ -25,7 +25,6 @@
 
 namespace filament {
 namespace backend {
-namespace metal {
 
 void initializeSupportedGpuFamilies(MetalContext* context) {
     auto& highestSupportedFamily = context->highestSupportedGpuFamily;
@@ -145,6 +144,5 @@ bool isInRenderPass(MetalContext* context) {
     return context->currentRenderPassEncoder != nil;
 }
 
-} // namespace metal
 } // namespace backend
 } // namespace filament

filament/backend/src/metal/MetalDriver.h

@@ -31,8 +31,6 @@ namespace backend {
 
 class MetalPlatform;
 
-namespace metal {
-
 class MetalBuffer;
 struct MetalUniformBuffer;
 struct MetalContext;
@@ -44,31 +42,32 @@ struct UniformBufferState;
 #endif
 
 class MetalDriver final : public DriverBase {
-    explicit MetalDriver(backend::MetalPlatform* platform) noexcept;
+    explicit MetalDriver(MetalPlatform* platform) noexcept;
     ~MetalDriver() noexcept override;
+    Dispatcher getDispatcher() const noexcept final;
 
 public:
-    static Driver* create(backend::MetalPlatform* platform);
+    static Driver* create(MetalPlatform* platform);
 
 private:
 
     friend class MetalSwapChain;
 
-    backend::MetalPlatform& mPlatform;
+    MetalPlatform& mPlatform;
 
     MetalContext* mContext;
 
     ShaderModel getShaderModel() const noexcept final;
 
     // Overrides the default implementation by wrapping the call to fn in an @autoreleasepool block.
-    void execute(std::function<void(void)> fn) noexcept final;
+    void execute(std::function<void(void)> const& fn) noexcept final;
 
     /*
      * Driver interface
      */
 
     template<typename T>
-    friend class backend::ConcreteDispatcher;
+    friend class ConcreteDispatcher;
 
 #define DECL_DRIVER_API(methodName, paramsDecl, params) \
     UTILS_ALWAYS_INLINE inline void methodName(paramsDecl);
@@ -86,7 +85,7 @@ private:
      * Memory management
      */
 
-    backend::HandleAllocatorMTL mHandleAllocator;
+    HandleAllocatorMTL mHandleAllocator;
 
     template<typename D>
     Handle<D> alloc_handle() {
@@ -126,7 +125,6 @@ private:
 
 };
 
-} // namespace metal
 } // namespace backend
 } // namespace filament
 

filament/backend/src/metal/MetalDriver.mm

@@ -41,22 +41,23 @@ namespace filament {
 namespace backend {
 
 Driver* MetalDriverFactory::create(MetalPlatform* const platform) {
-    return metal::MetalDriver::create(platform);
+    return MetalDriver::create(platform);
 }
 
-namespace metal {
-
 UTILS_NOINLINE
 Driver* MetalDriver::create(MetalPlatform* const platform) {
     assert_invariant(platform);
     return new MetalDriver(platform);
 }
 
-MetalDriver::MetalDriver(backend::MetalPlatform* platform) noexcept
-        : DriverBase(new ConcreteDispatcher<MetalDriver>()),
-        mPlatform(*platform),
-        mContext(new MetalContext),
-        mHandleAllocator("Handles", FILAMENT_METAL_HANDLE_ARENA_SIZE_IN_MB * 1024U * 1024U) {
+Dispatcher MetalDriver::getDispatcher() const noexcept {
+    return ConcreteDispatcher<MetalDriver>::make();
+}
+
+MetalDriver::MetalDriver(MetalPlatform* platform) noexcept
+        : mPlatform(*platform),
+          mContext(new MetalContext),
+          mHandleAllocator("Handles", FILAMENT_METAL_HANDLE_ARENA_SIZE_IN_MB * 1024U * 1024U) {
     mContext->driver = this;
 
     mContext->device = mPlatform.createDevice();
@@ -108,7 +109,7 @@ MetalDriver::MetalDriver(backend::MetalPlatform* platform) noexcept
     mContext->blitter = new MetalBlitter(*mContext);
 
     if (@available(iOS 12, *)) {
-        mContext->timerQueryImpl = new TimerQueryFence(*mContext);
+        mContext->timerQueryImpl = new MetalTimerQueryFence(*mContext);
     } else {
         mContext->timerQueryImpl = new TimerQueryNoop();
     }
@@ -149,18 +150,18 @@ void MetalDriver::beginFrame(int64_t monotonic_clock_ns, uint32_t frameId) {
 }
 
 void MetalDriver::setFrameScheduledCallback(Handle<HwSwapChain> sch,
-        backend::FrameScheduledCallback callback, void* user) {
+        FrameScheduledCallback callback, void* user) {
     auto* swapChain = handle_cast<MetalSwapChain>(sch);
     swapChain->setFrameScheduledCallback(callback, user);
 }
 
 void MetalDriver::setFrameCompletedCallback(Handle<HwSwapChain> sch,
-        backend::FrameCompletedCallback callback, void* user) {
+        FrameCompletedCallback callback, void* user) {
     auto* swapChain = handle_cast<MetalSwapChain>(sch);
     swapChain->setFrameCompletedCallback(callback, user);
 }
 
-void MetalDriver::execute(std::function<void(void)> fn) noexcept {
+void MetalDriver::execute(std::function<void(void)> const& fn) noexcept {
     @autoreleasepool {
         fn();
     }
@@ -291,7 +292,7 @@ void MetalDriver::createDefaultRenderTargetR(Handle<HwRenderTarget> rth, int dum
 
 void MetalDriver::createRenderTargetR(Handle<HwRenderTarget> rth,
         TargetBufferFlags targetBufferFlags, uint32_t width, uint32_t height,
-        uint8_t samples, backend::MRT color,
+        uint8_t samples, MRT color,
         TargetBufferInfo depth, TargetBufferInfo stencil) {
     // Clamp sample count to what the device supports.
     auto& sc = mContext->sampleCountLookup;
@@ -344,7 +345,7 @@ void MetalDriver::createSyncR(Handle<HwSync> sh, int) {
 }
 
 void MetalDriver::createSwapChainR(Handle<HwSwapChain> sch, void* nativeWindow, uint64_t flags) {
-    if (UTILS_UNLIKELY(flags & backend::SWAP_CHAIN_CONFIG_APPLE_CVPIXELBUFFER)) {
+    if (UTILS_UNLIKELY(flags & SWAP_CHAIN_CONFIG_APPLE_CVPIXELBUFFER)) {
         CVPixelBufferRef pixelBuffer = (CVPixelBufferRef) nativeWindow;
         construct_handle<MetalSwapChain>(sch, *mContext, pixelBuffer, flags);
     } else {
@@ -358,10 +359,6 @@ void MetalDriver::createSwapChainHeadlessR(Handle<HwSwapChain> sch,
     construct_handle<MetalSwapChain>(sch, *mContext, width, height, flags);
 }
 
-void MetalDriver::createStreamFromTextureIdR(Handle<HwStream>, intptr_t externalTextureId,
-        uint32_t width, uint32_t height) {
-}
-
 void MetalDriver::createTimerQueryR(Handle<HwTimerQuery> tqh, int) {
     // nothing to do, timer query was constructed in createTimerQueryS
 }
@@ -430,10 +427,6 @@ Handle<HwSwapChain> MetalDriver::createSwapChainHeadlessS() noexcept {
     return alloc_handle<MetalSwapChain>();
 }
 
-Handle<HwStream> MetalDriver::createStreamFromTextureIdS() noexcept {
-    return {};
-}
-
 Handle<HwTimerQuery> MetalDriver::createTimerQueryS() noexcept {
     // The handle must be constructed here, as a synchronous call to getTimerQueryValue might happen
     // before createTimerQueryR is executed.
@@ -569,7 +562,7 @@ Handle<HwStream> MetalDriver::createStreamAcquired() {
 }
 
 void MetalDriver::setAcquiredImage(Handle<HwStream> sh, void* image,
-        backend::CallbackHandler* handler, backend::StreamCallback cb, void* userData) {
+        CallbackHandler* handler, StreamCallback cb, void* userData) {
 }
 
 void MetalDriver::setStreamDimensions(Handle<HwStream> stream, uint32_t width,
@@ -581,7 +574,7 @@ int64_t MetalDriver::getStreamTimestamp(Handle<HwStream> stream) {
     return 0;
 }
 
-void MetalDriver::updateStreams(backend::DriverApi* driver) {
+void MetalDriver::updateStreams(DriverApi* driver) {
 
 }
 
@@ -1052,14 +1045,9 @@ void MetalDriver::readPixels(Handle<HwRenderTarget> src, uint32_t x, uint32_t y,
     }];
 }
 
-void MetalDriver::readStreamPixels(Handle<HwStream> sh, uint32_t x, uint32_t y, uint32_t width,
-        uint32_t height, PixelBufferDescriptor&& data) {
-
-}
-
 void MetalDriver::blit(TargetBufferFlags buffers,
-        Handle<HwRenderTarget> dst, backend::Viewport dstRect,
-        Handle<HwRenderTarget> src, backend::Viewport srcRect,
+        Handle<HwRenderTarget> dst, Viewport dstRect,
+        Handle<HwRenderTarget> src, Viewport srcRect,
         SamplerMagFilter filter) {
     // If we're the in middle of a render pass, finish it.
     // This condition should only occur during copyFrame. It's okay to end the render pass because
@@ -1166,7 +1154,7 @@ void MetalDriver::blit(TargetBufferFlags buffers,
     mContext->blitter->blit(getPendingCommandBuffer(mContext), args);
 }
 
-void MetalDriver::draw(backend::PipelineState ps, Handle<HwRenderPrimitive> rph, uint32_t instanceCount) {
+void MetalDriver::draw(PipelineState ps, Handle<HwRenderPrimitive> rph, uint32_t instanceCount) {
     ASSERT_PRECONDITION(mContext->currentRenderPassEncoder != nullptr,
             "Attempted to draw without a valid command encoder.");
     auto primitive = handle_cast<MetalRenderPrimitive>(rph);
@@ -1196,7 +1184,7 @@ void MetalDriver::draw(backend::PipelineState ps, Handle<HwRenderPrimitive> rph,
     if (depthAttachment) {
         depthPixelFormat = depthAttachment.getPixelFormat();
     }
-    metal::PipelineState pipelineState {
+    MetalPipelineState pipelineState {
         .vertexFunction = program->vertexFunction,
         .fragmentFunction = program->fragmentFunction,
         .vertexDescription = primitive->vertexDescription,
@@ -1304,15 +1292,15 @@ void MetalDriver::draw(backend::PipelineState ps, Handle<HwRenderPrimitive> rph,
         return mContext->samplerStateCache.getOrCreateState(s);
     };
 
-    id<MTLTexture> texturesToBindVertex[backend::MAX_VERTEX_SAMPLER_COUNT] = {};
-    id<MTLSamplerState> samplersToBindVertex[backend::MAX_VERTEX_SAMPLER_COUNT] = {};
+    id<MTLTexture> texturesToBindVertex[MAX_VERTEX_SAMPLER_COUNT] = {};
+    id<MTLSamplerState> samplersToBindVertex[MAX_VERTEX_SAMPLER_COUNT] = {};
 
     enumerateSamplerGroups(program, ShaderType::VERTEX,
             [this, &getTextureToBind, &getSamplerToBind, &texturesToBindVertex, &samplersToBindVertex](
                     const SamplerGroup::Sampler* sampler, uint8_t binding) {
         // We currently only support a max of MAX_VERTEX_SAMPLER_COUNT samplers. Ignore any additional
         // samplers that may be bound.
-        if (binding >= backend::MAX_VERTEX_SAMPLER_COUNT) {
+        if (binding >= MAX_VERTEX_SAMPLER_COUNT) {
             return;
         }
 
@@ -1336,21 +1324,21 @@ void MetalDriver::draw(backend::PipelineState ps, Handle<HwRenderPrimitive> rph,
         }
     }
 
-    NSRange vertexSamplerRange = NSMakeRange(0, backend::MAX_VERTEX_SAMPLER_COUNT);
+    NSRange vertexSamplerRange = NSMakeRange(0, MAX_VERTEX_SAMPLER_COUNT);
     [mContext->currentRenderPassEncoder setVertexTextures:texturesToBindVertex
                                                 withRange:vertexSamplerRange];
     [mContext->currentRenderPassEncoder setVertexSamplerStates:samplersToBindVertex
                                                      withRange:vertexSamplerRange];
 
-    id<MTLTexture> texturesToBindFragment[backend::MAX_FRAGMENT_SAMPLER_COUNT] = {};
-    id<MTLSamplerState> samplersToBindFragment[backend::MAX_FRAGMENT_SAMPLER_COUNT] = {};
+    id<MTLTexture> texturesToBindFragment[MAX_FRAGMENT_SAMPLER_COUNT] = {};
+    id<MTLSamplerState> samplersToBindFragment[MAX_FRAGMENT_SAMPLER_COUNT] = {};
 
     enumerateSamplerGroups(program, ShaderType::FRAGMENT,
             [this, &getTextureToBind, &getSamplerToBind, &texturesToBindFragment, &samplersToBindFragment](
                     const SamplerGroup::Sampler* sampler, uint8_t binding) {
         // We currently only support a max of MAX_FRAGMENT_SAMPLER_COUNT samplers. Ignore any additional
         // samplers that may be bound.
-        if (binding >= backend::MAX_FRAGMENT_SAMPLER_COUNT) {
+        if (binding >= MAX_FRAGMENT_SAMPLER_COUNT) {
             return;
         }
 
@@ -1374,7 +1362,7 @@ void MetalDriver::draw(backend::PipelineState ps, Handle<HwRenderPrimitive> rph,
         }
     }
 
-    NSRange fragmentSamplerRange = NSMakeRange(0, backend::MAX_FRAGMENT_SAMPLER_COUNT);
+    NSRange fragmentSamplerRange = NSMakeRange(0, MAX_FRAGMENT_SAMPLER_COUNT);
     [mContext->currentRenderPassEncoder setFragmentTextures:texturesToBindFragment
                                                   withRange:fragmentSamplerRange];
     [mContext->currentRenderPassEncoder setFragmentSamplerStates:samplersToBindFragment
@@ -1479,10 +1467,8 @@ void MetalDriver::enumerateBoundUniformBuffers(
     }
 }
 
-} // namespace metal
-
 // explicit instantiation of the Dispatcher
-template class ConcreteDispatcher<metal::MetalDriver>;
+template class ConcreteDispatcher<MetalDriver>;
 
 } // namespace backend
 } // namespace filament

filament/backend/src/metal/MetalDriverFactory.h

@@ -24,7 +24,7 @@ class Driver;
 
 class MetalDriverFactory {
 public:
-    static Driver* create(backend::MetalPlatform* platform);
+    static Driver* create(MetalPlatform* platform);
 };
 
 } // namespace backend

filament/backend/src/metal/MetalEnums.h

@@ -27,7 +27,6 @@
 
 namespace filament {
 namespace backend {
-namespace metal {
 
 struct MetalContext;
 
@@ -405,7 +404,6 @@ inline MTLTextureSwizzleChannels getSwizzleChannels(TextureSwizzle r, TextureSwi
             getSwizzle(a));
 }
 
-} // namespace metal
 } // namespace backend
 } // namespace filament
 

filament/backend/src/metal/MetalEnums.mm

@@ -20,7 +20,6 @@
 
 namespace filament {
 namespace backend {
-namespace metal {
 
 MTLPixelFormat getMetalFormat(MetalContext* context, TextureFormat format) noexcept {
     switch (format) {
@@ -207,6 +206,5 @@ MTLPixelFormat getMetalFormat(MetalContext* context, TextureFormat format) noexc
     return MTLPixelFormatInvalid;
 }
 
-} // namespace metal
 } // namespace backend
 } // namespace filament

filament/backend/src/metal/MetalExternalImage.h

@@ -24,7 +24,6 @@
 
 namespace filament {
 namespace backend {
-namespace metal {
 
 struct MetalContext;
 
@@ -129,7 +128,6 @@ private:
     } mSwizzle;
 };
 
-} // namespace metal
 } // namespace backend
 } // namespace filament
 

filament/backend/src/metal/MetalExternalImage.mm

@@ -32,7 +32,6 @@
 
 namespace filament {
 namespace backend {
-namespace metal {
 
 static const auto cvBufferDeleter = [](const void* buffer) {
     CVBufferRelease((CVMetalTextureRef) buffer);
@@ -300,6 +299,5 @@ id<MTLCommandBuffer> MetalExternalImage::encodeColorConversionPass(id<MTLTexture
     return commandBuffer;
 }
 
-} // namespace metal
 } // namespace backend
 } // namespace filament

filament/backend/src/metal/MetalHandles.h

@@ -40,7 +40,6 @@
 
 namespace filament {
 namespace backend {
-namespace metal {
 
 class MetalSwapChain : public HwSwapChain {
 public:
@@ -357,7 +356,6 @@ struct MetalTimerQuery : public HwTimerQuery {
     std::shared_ptr<Status> status;
 };
 
-} // namespace metal
 } // namespace backend
 } // namespace filament
 

filament/backend/src/metal/MetalHandles.mm

@@ -32,7 +32,6 @@
 
 namespace filament {
 namespace backend {
-namespace metal {
 
 static inline MTLTextureUsage getMetalTextureUsage(TextureUsage usage) {
     NSUInteger u = 0;
@@ -68,9 +67,8 @@ MetalSwapChain::MetalSwapChain(MetalContext& context, CAMetalLayer* nativeWindow
     }
 
     // Needed so we can use the SwapChain as a blit source.
-    if (flags & SwapChain::CONFIG_READABLE) {
-        nativeWindow.framebufferOnly = NO;
-    }
+    // Also needed for rendering directly into the SwapChain during refraction.
+    nativeWindow.framebufferOnly = NO;
 
     layer.device = context.device;
 }
@@ -81,7 +79,7 @@ MetalSwapChain::MetalSwapChain(MetalContext& context, int32_t width, int32_t hei
 
 MetalSwapChain::MetalSwapChain(MetalContext& context, CVPixelBufferRef pixelBuffer, uint64_t flags)
         : context(context), externalImage(context), type(SwapChainType::CVPIXELBUFFERREF) {
-    assert_invariant(flags & backend::SWAP_CHAIN_CONFIG_APPLE_CVPIXELBUFFER);
+    assert_invariant(flags & SWAP_CHAIN_CONFIG_APPLE_CVPIXELBUFFER);
     MetalExternalImage::assertWritableImage(pixelBuffer);
     externalImage.set(pixelBuffer);
     assert_invariant(externalImage.isValid());
@@ -224,7 +222,7 @@ void MetalSwapChain::scheduleFrameScheduledCallback() {
     }
 
     assert_invariant(drawable);
-    backend::FrameScheduledCallback callback = frameScheduledCallback;
+    FrameScheduledCallback callback = frameScheduledCallback;
     // This block strongly captures drawable to keep it alive until the handler executes.
     // We cannot simply reference this->drawable inside the block because the block would then only
     // capture the _this_ pointer (MetalSwapChain*) instead of the drawable.
@@ -245,12 +243,12 @@ void MetalSwapChain::scheduleFrameCompletedCallback() {
         return;
     }
 
-    backend::FrameCompletedCallback callback = frameCompletedCallback;
+    FrameCompletedCallback callback = frameCompletedCallback;
     void* userData = frameCompletedUserData;
     [getPendingCommandBuffer(&context) addCompletedHandler:^(id<MTLCommandBuffer> cb) {
         struct CallbackData {
             void* userData;
-            backend::FrameCompletedCallback callback;
+            FrameCompletedCallback callback;
         };
         CallbackData* data = new CallbackData();
         data->userData = userData;
@@ -369,7 +367,7 @@ MetalProgram::MetalProgram(id<MTLDevice> device, const Program& program) noexcep
         *shaderFunctions[i] = [library newFunctionWithName:@"main0"];
     }
 
-    // All stages of the program have compiled successfuly, this is a valid program.
+    // All stages of the program have compiled successfully, this is a valid program.
     isValid = true;
 
     // This calculates Metal resource binding indices. Filament's sampler bindings range from 0-31
@@ -1024,6 +1022,5 @@ FenceStatus MetalFence::wait(uint64_t timeoutNs) {
     return FenceStatus::ERROR;
 }
 
-} // namespace metal
 } // namespace backend
 } // namespace filament

filament/backend/src/metal/MetalResourceTracker.cpp

@@ -20,7 +20,6 @@
 
 namespace filament {
 namespace backend {
-namespace metal {
 
 bool MetalResourceTracker::trackResource(CommandBuffer buffer, Resource resource,
         ResourceDeleter deleter) {
@@ -53,6 +52,5 @@ void MetalResourceTracker::clearResources(CommandBuffer buffer) {
     mResources.erase(found);
 }
 
-} // namespace metal
 } // namespace backend
 } // namespace filament

filament/backend/src/metal/MetalResourceTracker.h

@@ -25,7 +25,6 @@
 
 namespace filament {
 namespace backend {
-namespace metal {
 
 /**
  * MetalResourceTracker is a simple utility that maps individual command buffers to a set of
@@ -76,7 +75,6 @@ private:
     std::mutex mMutex;
 };
 
-} // namespace metal
 } // namespace backend
 } // namespace filament
 

filament/backend/src/metal/MetalState.h

@@ -31,24 +31,21 @@
 namespace filament {
 namespace backend {
 
-inline bool operator==(const backend::SamplerParams& lhs, const backend::SamplerParams& rhs) {
+inline bool operator==(const SamplerParams& lhs, const SamplerParams& rhs) {
     return lhs.u == rhs.u;
 }
 
-namespace metal {
-
-static constexpr uint32_t MAX_VERTEX_ATTRIBUTE_COUNT = backend::MAX_VERTEX_ATTRIBUTE_COUNT;
 static constexpr uint32_t SAMPLER_GROUP_COUNT = Program::BINDING_COUNT;
-static constexpr uint32_t SAMPLER_BINDING_COUNT = backend::MAX_SAMPLER_COUNT;
+static constexpr uint32_t SAMPLER_BINDING_COUNT = MAX_SAMPLER_COUNT;
 static constexpr uint32_t VERTEX_BUFFER_START = Program::BINDING_COUNT;
 
 // The "zero" buffer is a small buffer for missing attributes that resides in the vertex slot
 // immediately following any user-provided vertex buffers.
-static constexpr uint32_t ZERO_VERTEX_BUFFER = backend::MAX_VERTEX_BUFFER_COUNT;
+static constexpr uint32_t ZERO_VERTEX_BUFFER = MAX_VERTEX_BUFFER_COUNT;
 
 // The total number of vertex buffer "slots" that the Metal backend can bind.
 // + 1 to account for the zero buffer.
-static constexpr uint32_t VERTEX_BUFFER_COUNT = backend::MAX_VERTEX_BUFFER_COUNT + 1;
+static constexpr uint32_t VERTEX_BUFFER_COUNT = MAX_VERTEX_BUFFER_COUNT + 1;
 
 // Forward declarations necessary here, definitions at end of file.
 inline bool operator==(const MTLViewport& lhs, const MTLViewport& rhs);
@@ -173,7 +170,7 @@ private:
 };
 
 // StateTracker keeps track of state changes made to a Metal command encoder.
-// Different kinds of state, like pipeline state, uniform buffer state, etc, are passed to the
+// Different kinds of state, like pipeline state, uniform buffer state, etc., are passed to the
 // current Metal command encoder and persist throughout the lifetime of the encoder (a frame).
 // StateTracker is used to prevent calling redundant state change methods.
 template<typename StateType>
@@ -212,7 +209,7 @@ private:
 
 // Pipeline state
 
-struct PipelineState {
+struct MetalPipelineState {
     id<MTLFunction> vertexFunction = nil;                                      // 8 bytes
     id<MTLFunction> fragmentFunction = nil;                                    // 8 bytes
     VertexDescription vertexDescription;                                       // 528 bytes
@@ -223,7 +220,7 @@ struct PipelineState {
     bool colorWrite = true;                                                    // 1 byte
     char padding[7] = { 0 };                                                   // 7 bytes
 
-    bool operator==(const PipelineState& rhs) const noexcept {
+    bool operator==(const MetalPipelineState& rhs) const noexcept {
         return (
                 this->vertexFunction == rhs.vertexFunction &&
                 this->fragmentFunction == rhs.fragmentFunction &&
@@ -237,23 +234,23 @@ struct PipelineState {
         );
     }
 
-    bool operator!=(const PipelineState& rhs) const noexcept {
+    bool operator!=(const MetalPipelineState& rhs) const noexcept {
         return !operator==(rhs);
     }
 };
 
 // This assert checks that the struct is the size we expect without any "hidden" padding bytes
 // inserted by the compiler.
-static_assert(sizeof(PipelineState) == 688, "PipelineState unexpected size.");
+static_assert(sizeof(MetalPipelineState) == 688, "MetalPipelineState unexpected size.");
 
 struct PipelineStateCreator {
-    id<MTLRenderPipelineState> operator()(id<MTLDevice> device, const PipelineState& state)
+    id<MTLRenderPipelineState> operator()(id<MTLDevice> device, const MetalPipelineState& state)
             noexcept;
 };
 
-using PipelineStateTracker = StateTracker<PipelineState>;
+using PipelineStateTracker = StateTracker<MetalPipelineState>;
 
-using PipelineStateCache = StateCache<PipelineState, id<MTLRenderPipelineState>,
+using PipelineStateCache = StateCache<MetalPipelineState, id<MTLRenderPipelineState>,
         PipelineStateCreator>;
 
 // Depth-stencil State
@@ -315,7 +312,7 @@ using UniformBufferStateTracker = StateTracker<UniformBufferState>;
 // Sampler states
 
 struct SamplerState {
-    backend::SamplerParams samplerParams;
+    SamplerParams samplerParams;
     uint32_t minLod = 0;
     uint32_t maxLod = UINT_MAX;
 
@@ -343,7 +340,6 @@ using SamplerStateCache = StateCache<SamplerState, id<MTLSamplerState>, SamplerS
 using CullModeStateTracker = StateTracker<MTLCullMode>;
 using WindingStateTracker = StateTracker<MTLWinding>;
 
-} // namespace metal
 } // namespace backend
 } // namespace filament
 

filament/backend/src/metal/MetalState.mm

@@ -20,10 +20,9 @@
 
 namespace filament {
 namespace backend {
-namespace metal {
 
 id<MTLRenderPipelineState> PipelineStateCreator::operator()(id<MTLDevice> device,
-        const PipelineState& state) noexcept {
+        const MetalPipelineState& state) noexcept {
     MTLRenderPipelineDescriptor* descriptor = [MTLRenderPipelineDescriptor new];
 
     // Shader Functions
@@ -105,7 +104,7 @@ id<MTLDepthStencilState> DepthStateCreator::operator()(id<MTLDevice> device,
 
 id<MTLSamplerState> SamplerStateCreator::operator()(id<MTLDevice> device,
         const SamplerState& state) noexcept {
-    backend::SamplerParams params = state.samplerParams;
+    SamplerParams params = state.samplerParams;
     MTLSamplerDescriptor* samplerDescriptor = [MTLSamplerDescriptor new];
     samplerDescriptor.minFilter = getFilter(params.filterMin);
     samplerDescriptor.magFilter = getFilter(params.filterMag);
@@ -133,6 +132,5 @@ id<MTLSamplerState> SamplerStateCreator::operator()(id<MTLDevice> device,
     return [device newSamplerStateWithDescriptor:samplerDescriptor];
 }
 
-} // namespace metal
 } // namespace backend
 } // namespace filament

filament/backend/src/metal/MetalTimerQuery.h

@@ -23,14 +23,13 @@
 
 namespace filament {
 namespace backend {
-namespace metal {
 
 struct MetalTimerQuery;
 struct MetalContext;
 
-class TimerQueryInterface {
+class MetalTimerQueryInterface {
 public:
-    virtual ~TimerQueryInterface();
+    virtual ~MetalTimerQueryInterface();
     virtual void beginTimeElapsedQuery(MetalTimerQuery* query) = 0;
     virtual void endTimeElapsedQuery(MetalTimerQuery* query) = 0;
     virtual bool getQueryResult(MetalTimerQuery* query, uint64_t* outElapsedTime) = 0;
@@ -41,9 +40,9 @@ protected:
 
 // Uses MTLSharedEvents to implement timer queries.
 // Only available on >= iOS 12.0.
-class API_AVAILABLE(ios(12.0)) TimerQueryFence : public TimerQueryInterface {
+class API_AVAILABLE(ios(12.0)) MetalTimerQueryFence : public MetalTimerQueryInterface {
 public:
-    explicit TimerQueryFence(MetalContext& context) : mContext(context) {}
+    explicit MetalTimerQueryFence(MetalContext& context) : mContext(context) {}
 
     void beginTimeElapsedQuery(MetalTimerQuery* query) override;
     void endTimeElapsedQuery(MetalTimerQuery* query) override;
@@ -53,14 +52,13 @@ private:
     MetalContext& mContext;
 };
 
-class TimerQueryNoop : public TimerQueryInterface {
+class TimerQueryNoop : public MetalTimerQueryInterface {
 public:
     void beginTimeElapsedQuery(MetalTimerQuery* query) override {}
     void endTimeElapsedQuery(MetalTimerQuery* query) override {}
     bool getQueryResult(MetalTimerQuery* query, uint64_t* outElapsedTime) override;
 };
 
-} // namespace metal
 } // namespace backend
 } // namespace filament
 

filament/backend/src/metal/MetalTimerQuery.mm

@@ -20,11 +20,10 @@
 
 namespace filament {
 namespace backend {
-namespace metal {
 
-TimerQueryInterface::~TimerQueryInterface() = default;
+MetalTimerQueryInterface::~MetalTimerQueryInterface() = default;
 
-void TimerQueryFence::beginTimeElapsedQuery(MetalTimerQuery* query) {
+void MetalTimerQueryFence::beginTimeElapsedQuery(MetalTimerQuery* query) {
     auto* fence = new MetalFence(mContext);
     fence->encode();
     query->status->elapsed = 0;
@@ -41,7 +40,7 @@ void TimerQueryFence::beginTimeElapsedQuery(MetalTimerQuery* query) {
     });
 }
 
-void TimerQueryFence::endTimeElapsedQuery(MetalTimerQuery* query) {
+void MetalTimerQueryFence::endTimeElapsedQuery(MetalTimerQuery* query) {
     auto* fence = new MetalFence(mContext);
     fence->encode();
 
@@ -57,7 +56,7 @@ void TimerQueryFence::endTimeElapsedQuery(MetalTimerQuery* query) {
     });
 }
 
-bool TimerQueryFence::getQueryResult(MetalTimerQuery* query, uint64_t* outElapsedTime) {
+bool MetalTimerQueryFence::getQueryResult(MetalTimerQuery* query, uint64_t* outElapsedTime) {
     if (!query->status->available.load()) {
         return false;
     }
@@ -71,6 +70,5 @@ bool TimerQueryNoop::getQueryResult(MetalTimerQuery* query, uint64_t* outElapsed
     return false;
 }
 
-} // namespace metal
 } // namespace backend
 } // namespace filament

filament/backend/src/metal/MetalUtils.h

@@ -19,7 +19,7 @@
 
 #include <Metal/Metal.h>
 
-namespace filament::backend::metal {
+namespace filament::backend {
 
 /**
  * Creates a texture view of the passed-in texture with the given swizzle. If swizzle is the default
@@ -42,6 +42,6 @@ id<MTLTexture> createTextureViewWithSwizzle(id<MTLTexture> texture,
  */
 id<MTLTexture> createTextureViewWithSingleSlice(id<MTLTexture> texture, NSUInteger slice);
 
-} // namespace filament::backend::metal
+} // namespace filament::backend
 
 #endif //TNT_FILAMENT_DRIVER_METALUTILS_H

filament/backend/src/metal/MetalUtils.mm

@@ -16,7 +16,7 @@
 
 #include "MetalUtils.h"
 
-namespace filament::backend::metal {
+namespace filament::backend {
 
 id<MTLTexture> createTextureViewWithSwizzle(id<MTLTexture> texture,
         MTLTextureSwizzleChannels swizzle) {
@@ -48,4 +48,4 @@ id<MTLTexture> createTextureViewWithSingleSlice(id<MTLTexture> texture, NSUInteg
                                            slices:NSMakeRange(slice, 1)];
 }
 
-}
+} // namespace filament::backend

filament/backend/src/noop/NoopDriver.cpp

@@ -17,20 +17,21 @@
 #include "noop/NoopDriver.h"
 #include "CommandStreamDispatcher.h"
 
-namespace filament {
-
-using namespace backend;
+namespace filament::backend {
 
 Driver* NoopDriver::create() {
     return new NoopDriver();
 }
 
-NoopDriver::NoopDriver() noexcept : DriverBase(new ConcreteDispatcher<NoopDriver>()) {
-}
+NoopDriver::NoopDriver() noexcept = default;
 
 NoopDriver::~NoopDriver() noexcept = default;
 
-backend::ShaderModel NoopDriver::getShaderModel() const noexcept {
+Dispatcher NoopDriver::getDispatcher() const noexcept {
+    return ConcreteDispatcher<NoopDriver>::make();
+}
+
+ShaderModel NoopDriver::getShaderModel() const noexcept {
 #if defined(__ANDROID__) || defined(IOS) || defined(__EMSCRIPTEN__)
     return ShaderModel::GL_ES_30;
 #else
@@ -39,7 +40,7 @@ backend::ShaderModel NoopDriver::getShaderModel() const noexcept {
 }
 
 // explicit instantiation of the Dispatcher
-template class backend::ConcreteDispatcher<NoopDriver>;
+template class ConcreteDispatcher<NoopDriver>;
 
 
 void NoopDriver::terminate() {
@@ -52,12 +53,12 @@ void NoopDriver::beginFrame(int64_t monotonic_clock_ns, uint32_t frameId) {
 }
 
 void NoopDriver::setFrameScheduledCallback(Handle<HwSwapChain> sch,
-        backend::FrameScheduledCallback callback, void* user) {
+        FrameScheduledCallback callback, void* user) {
 
 }
 
 void NoopDriver::setFrameCompletedCallback(Handle<HwSwapChain> sch,
-        backend::FrameCompletedCallback callback, void* user) {
+        FrameCompletedCallback callback, void* user) {
 
 }
 
@@ -118,7 +119,7 @@ Handle<HwStream> NoopDriver::createStreamAcquired() {
 }
 
 void NoopDriver::setAcquiredImage(Handle<HwStream> sh, void* image,
-        backend::CallbackHandler* handler, backend::StreamCallback cb, void* userData) {
+        CallbackHandler* handler, StreamCallback cb, void* userData) {
 }
 
 void NoopDriver::setStreamDimensions(Handle<HwStream> sh, uint32_t width, uint32_t height) {
@@ -148,7 +149,7 @@ bool NoopDriver::isTextureSwizzleSupported() {
     return true;
 }
 
-bool NoopDriver::isTextureFormatMipmappable(backend::TextureFormat format) {
+bool NoopDriver::isTextureFormatMipmappable(TextureFormat format) {
     return true;
 }
 
@@ -181,7 +182,7 @@ math::float2 NoopDriver::getClipSpaceParams() {
 }
 
 uint8_t NoopDriver::getMaxDrawBuffers() {
-    return backend::MRT::MAX_SUPPORTED_RENDER_TARGET_COUNT;
+    return MRT::MAX_SUPPORTED_RENDER_TARGET_COUNT;
 }
 
 void NoopDriver::updateIndexBuffer(Handle<HwIndexBuffer> ibh, BufferDescriptor&& p,
@@ -307,14 +308,9 @@ void NoopDriver::readPixels(Handle<HwRenderTarget> src,
     scheduleDestroy(std::move(p));
 }
 
-void NoopDriver::readStreamPixels(Handle<HwStream> sh, uint32_t x, uint32_t y, uint32_t width,
-        uint32_t height, PixelBufferDescriptor&& p) {
-    scheduleDestroy(std::move(p));
-}
-
 void NoopDriver::blit(TargetBufferFlags buffers,
-        Handle<HwRenderTarget> dst, backend::Viewport dstRect,
-        Handle<HwRenderTarget> src, backend::Viewport srcRect,
+        Handle<HwRenderTarget> dst, Viewport dstRect,
+        Handle<HwRenderTarget> src, Viewport srcRect,
         SamplerMagFilter filter) {
 }
 

filament/backend/src/noop/NoopDriver.h

@@ -14,32 +14,33 @@
  * limitations under the License.
  */
 
-#ifndef TNT_FILAMENT_DRIVER_NOOPDRIVER_H
-#define TNT_FILAMENT_DRIVER_NOOPDRIVER_H
+#ifndef TNT_FILAMENT_BACKEND_NOOPDRIVER_H
+#define TNT_FILAMENT_BACKEND_NOOPDRIVER_H
 
 #include "private/backend/Driver.h"
 #include "DriverBase.h"
 
 #include <utils/compiler.h>
 
-namespace filament {
+namespace filament::backend {
 
-class NoopDriver final : public backend::DriverBase {
+class NoopDriver final : public DriverBase {
     NoopDriver() noexcept;
     ~NoopDriver() noexcept override;
+    Dispatcher getDispatcher() const noexcept final;
 
 public:
-    static backend::Driver* create();
+    static Driver* create();
 
 private:
-    backend::ShaderModel getShaderModel() const noexcept final;
+    ShaderModel getShaderModel() const noexcept final;
 
     /*
      * Driver interface
      */
 
     template<typename T>
-    friend class backend::ConcreteDispatcher;
+    friend class ConcreteDispatcher;
 
 #define DECL_DRIVER_API(methodName, paramsDecl, params) \
     UTILS_ALWAYS_INLINE inline void methodName(paramsDecl);
@@ -57,4 +58,4 @@ private:
 
 } // namespace filament
 
-#endif // TNT_FILAMENT_DRIVER_NOOPDRIVER_H
+#endif // TNT_FILAMENT_BACKEND_NOOPDRIVER_H

filament/backend/src/noop/PlatformNoop.cpp

@@ -18,9 +18,9 @@
 
 #include "noop/NoopDriver.h"
 
-namespace filament {
+namespace filament::backend {
 
-backend::Driver* PlatformNoop::createDriver(void* const sharedGLContext) noexcept {
+Driver* PlatformNoop::createDriver(void* const sharedGLContext) noexcept {
     return NoopDriver::create();
 }
 

filament/backend/src/noop/PlatformNoop.h

@@ -14,15 +14,15 @@
  * limitations under the License.
  */
 
-#ifndef TNT_FILAMENT_DRIVER_NOOP_PLATFORM_NOOP_H
-#define TNT_FILAMENT_DRIVER_NOOP_PLATFORM_NOOP_H
+#ifndef TNT_FILAMENT_BACKEND_NOOP_PLATFORM_NOOP_H
+#define TNT_FILAMENT_BACKEND_NOOP_PLATFORM_NOOP_H
 
 #include <backend/DriverEnums.h>
 #include <backend/Platform.h>
 
-namespace filament {
+namespace filament::backend {
 
-class PlatformNoop final : public backend::DefaultPlatform {
+class PlatformNoop final : public DefaultPlatform {
 public:
 
     int getOSVersion() const noexcept final { return 0; }
@@ -31,9 +31,9 @@ public:
 
 protected:
 
-    backend::Driver* createDriver(void* sharedContext) noexcept override;
+    Driver* createDriver(void* sharedContext) noexcept override;
 };
 
 } // namespace filament
 
-#endif // TNT_FILAMENT_DRIVER_NOOP_PLATFORM_NOOP_H
+#endif // TNT_FILAMENT_BACKEND_NOOP_PLATFORM_NOOP_H

filament/backend/src/opengl/GLUtils.cpp

@@ -20,7 +20,7 @@
 
 #include "private/backend/Driver.h"
 
-namespace filament {
+namespace filament::backend {
 
 using namespace backend;
 using namespace utils;
@@ -121,5 +121,21 @@ void assertFramebufferStatus(io::ostream& out, GLenum target, const char* functi
     }
 }
 
+bool unordered_string_set::has(std::string_view str) const noexcept {
+    return find(str) != end();
+}
+
+unordered_string_set split(const char* extensions) noexcept {
+    unordered_string_set set;
+    std::string_view string(extensions);
+    do {
+        auto p = string.find(' ');
+        p = (p == std::string_view::npos ? string.length() : p);
+        set.emplace(string.data(), p);
+        string.remove_prefix(p == string.length() ? p : p + 1);
+    } while(!string.empty());
+    return set;
+}
+
 } // namespace GLUtils
-} // namespace filament
+} // namespace filament::backend

filament/backend/src/opengl/GLUtils.h

@@ -14,22 +14,22 @@
  * limitations under the License.
  */
 
-#ifndef TNT_FILAMENT_DRIVER_GLUTILS_H
-#define TNT_FILAMENT_DRIVER_GLUTILS_H
+#ifndef TNT_FILAMENT_BACKEND_OPENGL_GLUTILS_H
+#define TNT_FILAMENT_BACKEND_OPENGL_GLUTILS_H
 
 #include <utils/compiler.h>
 #include <utils/Log.h>
 
 #include <backend/DriverEnums.h>
 
-#include <string>
+#include <string_view>
 #include <unordered_set>
 
 #include <string.h>
 
 #include "gl_headers.h"
 
-namespace filament {
+namespace filament::backend {
 namespace GLUtils {
 
 const char* getGLError(GLenum error) noexcept;
@@ -44,15 +44,12 @@ void assertFramebufferStatus(utils::io::ostream& out, GLenum target, const char*
 #   define CHECK_GL_ERROR(out)
 #   define CHECK_GL_FRAMEBUFFER_STATUS(out, target)
 #else
-#   ifdef _MSC_VER
-#       define __PRETTY_FUNCTION__ __FUNCSIG__
-#   endif
-#   define CHECK_GL_ERROR(out) { GLUtils::assertGLError(out, __PRETTY_FUNCTION__, __LINE__); }
-#   define CHECK_GL_FRAMEBUFFER_STATUS(out, target) { GLUtils::checkFramebufferStatus(out, target, __PRETTY_FUNCTION__, __LINE__); }
+#   define CHECK_GL_ERROR(out) { GLUtils::assertGLError(out, __func__, __LINE__); }
+#   define CHECK_GL_FRAMEBUFFER_STATUS(out, target) { GLUtils::checkFramebufferStatus(out, target, __func__, __LINE__); }
 #endif
 
-constexpr inline GLuint getComponentCount(backend::ElementType type) noexcept {
-    using ElementType = backend::ElementType;
+constexpr inline GLuint getComponentCount(ElementType type) noexcept {
+    using ElementType = ElementType;
     switch (type) {
         case ElementType::BYTE:
         case ElementType::UBYTE:
@@ -91,35 +88,35 @@ constexpr inline GLuint getComponentCount(backend::ElementType type) noexcept {
 // Our enums to GLenum conversions
 // ------------------------------------------------------------------------------------------------
 
-constexpr inline GLbitfield getAttachmentBitfield(backend::TargetBufferFlags flags) noexcept {
+constexpr inline GLbitfield getAttachmentBitfield(TargetBufferFlags flags) noexcept {
     GLbitfield mask = 0;
-    if (any(flags & backend::TargetBufferFlags::COLOR_ALL)) {
+    if (any(flags & TargetBufferFlags::COLOR_ALL)) {
         mask |= (GLbitfield)GL_COLOR_BUFFER_BIT;
     }
-    if (any(flags & backend::TargetBufferFlags::DEPTH)) {
+    if (any(flags & TargetBufferFlags::DEPTH)) {
         mask |= (GLbitfield)GL_DEPTH_BUFFER_BIT;
     }
-    if (any(flags & backend::TargetBufferFlags::STENCIL)) {
+    if (any(flags & TargetBufferFlags::STENCIL)) {
         mask |= (GLbitfield)GL_STENCIL_BUFFER_BIT;
     }
     return mask;
 }
 
-constexpr inline GLenum getBufferUsage(backend::BufferUsage usage) noexcept {
+constexpr inline GLenum getBufferUsage(BufferUsage usage) noexcept {
     switch (usage) {
-        case backend::BufferUsage::STATIC:
+        case BufferUsage::STATIC:
             return GL_STATIC_DRAW;
-        case backend::BufferUsage::DYNAMIC:
-        case backend::BufferUsage::STREAM:
+        case BufferUsage::DYNAMIC:
+        case BufferUsage::STREAM:
             return GL_DYNAMIC_DRAW;
     }
 }
 
-constexpr inline GLenum getBufferBindingType(backend::BufferObjectBinding bindingType) noexcept {
+constexpr inline GLenum getBufferBindingType(BufferObjectBinding bindingType) noexcept {
     switch (bindingType) {
-        case backend::BufferObjectBinding::VERTEX:
+        case BufferObjectBinding::VERTEX:
             return GL_ARRAY_BUFFER;
-        case backend::BufferObjectBinding::UNIFORM:
+        case BufferObjectBinding::UNIFORM:
             return GL_UNIFORM_BUFFER;
     }
 }
@@ -128,8 +125,8 @@ constexpr inline GLboolean getNormalization(bool normalized) noexcept {
     return GLboolean(normalized ? GL_TRUE : GL_FALSE);
 }
 
-constexpr inline GLenum getComponentType(backend::ElementType type) noexcept {
-    using ElementType = backend::ElementType;
+constexpr inline GLenum getComponentType(ElementType type) noexcept {
+    using ElementType = ElementType;
     switch (type) {
         case ElementType::BYTE:
         case ElementType::BYTE2:
@@ -173,8 +170,8 @@ constexpr inline GLenum getCubemapTarget(uint16_t layer) noexcept {
     return GL_TEXTURE_CUBE_MAP_POSITIVE_X + layer;
 }
 
-constexpr inline GLenum getWrapMode(backend::SamplerWrapMode mode) noexcept {
-    using SamplerWrapMode = backend::SamplerWrapMode;
+constexpr inline GLenum getWrapMode(SamplerWrapMode mode) noexcept {
+    using SamplerWrapMode = SamplerWrapMode;
     switch (mode) {
         case SamplerWrapMode::REPEAT:
             return GL_REPEAT;
@@ -185,8 +182,8 @@ constexpr inline GLenum getWrapMode(backend::SamplerWrapMode mode) noexcept {
     }
 }
 
-constexpr inline GLenum getTextureFilter(backend::SamplerMinFilter filter) noexcept {
-    using SamplerMinFilter = backend::SamplerMinFilter;
+constexpr inline GLenum getTextureFilter(SamplerMinFilter filter) noexcept {
+    using SamplerMinFilter = SamplerMinFilter;
     switch (filter) {
         case SamplerMinFilter::NEAREST:
         case SamplerMinFilter::LINEAR:
@@ -200,13 +197,13 @@ constexpr inline GLenum getTextureFilter(backend::SamplerMinFilter filter) noexc
     }
 }
 
-constexpr inline GLenum getTextureFilter(backend::SamplerMagFilter filter) noexcept {
+constexpr inline GLenum getTextureFilter(SamplerMagFilter filter) noexcept {
     return GL_NEAREST + GLenum(filter);
 }
 
 
-constexpr inline GLenum getBlendEquationMode(backend::BlendEquation mode) noexcept {
-    using BlendEquation = backend::BlendEquation;
+constexpr inline GLenum getBlendEquationMode(BlendEquation mode) noexcept {
+    using BlendEquation = BlendEquation;
     switch (mode) {
         case BlendEquation::ADD:               return GL_FUNC_ADD;
         case BlendEquation::SUBTRACT:          return GL_FUNC_SUBTRACT;
@@ -216,8 +213,8 @@ constexpr inline GLenum getBlendEquationMode(backend::BlendEquation mode) noexce
     }
 }
 
-constexpr inline GLenum getBlendFunctionMode(backend::BlendFunction mode) noexcept {
-    using BlendFunction = backend::BlendFunction;
+constexpr inline GLenum getBlendFunctionMode(BlendFunction mode) noexcept {
+    using BlendFunction = BlendFunction;
     switch (mode) {
         case BlendFunction::ZERO:                  return GL_ZERO;
         case BlendFunction::ONE:                   return GL_ONE;
@@ -233,13 +230,13 @@ constexpr inline GLenum getBlendFunctionMode(backend::BlendFunction mode) noexce
     }
 }
 
-constexpr inline GLenum getTextureCompareMode(backend::SamplerCompareMode mode) noexcept {
-    return mode == backend::SamplerCompareMode::NONE ?
+constexpr inline GLenum getTextureCompareMode(SamplerCompareMode mode) noexcept {
+    return mode == SamplerCompareMode::NONE ?
            GL_NONE : GL_COMPARE_REF_TO_TEXTURE;
 }
 
-constexpr inline GLenum getTextureCompareFunc(backend::SamplerCompareFunc func) noexcept {
-    using SamplerCompareFunc = backend::SamplerCompareFunc;
+constexpr inline GLenum getTextureCompareFunc(SamplerCompareFunc func) noexcept {
+    using SamplerCompareFunc = SamplerCompareFunc;
     switch (func) {
         case SamplerCompareFunc::LE:    return GL_LEQUAL;
         case SamplerCompareFunc::GE:    return GL_GEQUAL;
@@ -252,12 +249,12 @@ constexpr inline GLenum getTextureCompareFunc(backend::SamplerCompareFunc func)
     }
 }
 
-constexpr inline GLenum getDepthFunc(backend::SamplerCompareFunc func) noexcept {
+constexpr inline GLenum getDepthFunc(SamplerCompareFunc func) noexcept {
     return getTextureCompareFunc(func);
 }
 
-constexpr inline GLenum getFormat(backend::PixelDataFormat format) noexcept {
-    using PixelDataFormat = backend::PixelDataFormat;
+constexpr inline GLenum getFormat(PixelDataFormat format) noexcept {
+    using PixelDataFormat = PixelDataFormat;
     switch (format) {
         case PixelDataFormat::R:                return GL_RED;
         case PixelDataFormat::R_INTEGER:        return GL_RED_INTEGER;
@@ -274,8 +271,8 @@ constexpr inline GLenum getFormat(backend::PixelDataFormat format) noexcept {
     }
 }
 
-constexpr inline GLenum getType(backend::PixelDataType type) noexcept {
-    using PixelDataType = backend::PixelDataType;
+constexpr inline GLenum getType(PixelDataType type) noexcept {
+    using PixelDataType = PixelDataType;
     switch (type) {
         case PixelDataType::UBYTE:                return GL_UNSIGNED_BYTE;
         case PixelDataType::BYTE:                 return GL_BYTE;
@@ -292,8 +289,8 @@ constexpr inline GLenum getType(backend::PixelDataType type) noexcept {
     }
 }
 
-constexpr inline GLenum getSwizzleChannel(backend::TextureSwizzle c) noexcept {
-    using TextureSwizzle = backend::TextureSwizzle;
+constexpr inline GLenum getSwizzleChannel(TextureSwizzle c) noexcept {
+    using TextureSwizzle = TextureSwizzle;
     switch (c) {
         case TextureSwizzle::SUBSTITUTE_ZERO:
             return GL_ZERO;
@@ -313,8 +310,8 @@ constexpr inline GLenum getSwizzleChannel(backend::TextureSwizzle c) noexcept {
 // clang looses it on this one, and generates a huge jump table when
 // inlined. So we don't  mark it as inline (only constexpr) which solves the problem,
 // strangely, when not inlined, clang simply generates an array lookup.
-constexpr /* inline */ GLenum getInternalFormat(backend::TextureFormat format) noexcept {
-    using TextureFormat = backend::TextureFormat;
+constexpr /* inline */ GLenum getInternalFormat(TextureFormat format) noexcept {
+    using TextureFormat = TextureFormat;
     switch (format) {
         // 8-bits per element
         case TextureFormat::R8:                return GL_R8;
@@ -507,29 +504,14 @@ constexpr /* inline */ GLenum getInternalFormat(backend::TextureFormat format) n
     }
 }
 
-class unordered_string_set : public std::unordered_set<std::string> {
+class unordered_string_set : public std::unordered_set<std::string_view> {
 public:
-    bool has(const char* str) {
-        return find(std::string(str)) != end();
-    }
+    bool has(std::string_view str) const noexcept;
 };
 
-inline unordered_string_set split(const char* spacedList) {
-    unordered_string_set set;
-    const char* current = spacedList;
-    const char* head = current;
-    do {
-        head = strchr(current, ' ');
-        std::string s(current, head ? head - current : strlen(current));
-        if (s.length()) {
-            set.insert(std::move(s));
-        }
-        current = head + 1;
-    } while (head);
-    return set;
-}
+unordered_string_set split(const char* extensions) noexcept;
 
 } // namespace GLUtils
-} // namespace filament
+} // namespace filament::backend
 
-#endif // TNT_FILAMENT_DRIVER_GLUTILS_H
+#endif // TNT_FILAMENT_BACKEND_OPENGL_GLUTILS_H

filament/backend/src/opengl/NullGLES.h

@@ -14,8 +14,8 @@
  * limitations under the License.
  */
 
-#ifndef TNT_FILAMENT_DRIVER_NULLGLES_H
-#define TNT_FILAMENT_DRIVER_NULLGLES_H
+#ifndef TNT_FILAMENT_BACKEND_OPENGL_NULLGLES_H
+#define TNT_FILAMENT_BACKEND_OPENGL_NULLGLES_H
 
 /*
  * This is used for debugging (stubbing out GLES calls)
@@ -27,7 +27,7 @@
  *
  */
 
-namespace filament {
+namespace filament::backend {
 namespace nullgles {
 
 inline void glScissor(GLint, GLint, GLsizei, GLsizei) { }
@@ -81,6 +81,6 @@ inline GLenum glGetError() { return GL_NO_ERROR; }
 // turn GLES calls defined above into no-ops
 //using namespace nullgles;
 
-} // namespace filament
+} // namespace filament::backend
 
-#endif // TNT_FILAMENT_DRIVER_NULLGLES_H
+#endif // TNT_FILAMENT_BACKEND_OPENGL_NULLGLES_H

filament/backend/src/opengl/OpenGLBlitter.cpp

@@ -1,215 +0,0 @@
-/*
- * Copyright (C) 2017 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 "OpenGLBlitter.h"
-
-#include "GLUtils.h"
-#include "OpenGLContext.h"
-
-#include <utils/compiler.h>
-#include <utils/Log.h>
-
-#include <math/vec2.h>
-
-using namespace filament::math;
-using namespace utils;
-
-namespace filament {
-
-static const char s_vertexES[] = R"SHADER(#version 300 es
-in vec4 pos;
-void main() {
-    gl_Position = pos;
-}
-)SHADER";
-
-static const char s_vertexGL[] = R"SHADER(#version 410 core
-in vec4 pos;
-void main() {
-    gl_Position = pos;
-}
-)SHADER";
-
-static const char s_fragmentES[] = R"SHADER(#version 300 es
-#extension GL_OES_EGL_image_external_essl3 : enable
-precision mediump float;
-uniform samplerExternalOES sampler;
-out vec4 fragColor;
-void main() {
-    fragColor = texelFetch(sampler, ivec2(gl_FragCoord.xy), 0);
-}
-)SHADER";
-
-static const char s_fragmentGL[] = R"SHADER(#version 410 core
-precision mediump float;
-uniform sampler2D sampler;
-out vec4 fragColor;
-void main() {
-    fragColor = texelFetch(sampler, ivec2(gl_FragCoord.xy), 0);
-}
-)SHADER";
-
-void OpenGLBlitter::init() noexcept {
-    glGenSamplers(1, &mSampler);
-    glSamplerParameteri(mSampler, GL_TEXTURE_MIN_FILTER,   GL_NEAREST);
-    glSamplerParameteri(mSampler, GL_TEXTURE_MAG_FILTER,   GL_NEAREST);
-    glSamplerParameteri(mSampler, GL_TEXTURE_WRAP_S,       GL_CLAMP_TO_EDGE);
-    glSamplerParameteri(mSampler, GL_TEXTURE_WRAP_T,       GL_CLAMP_TO_EDGE);
-    glSamplerParameteri(mSampler, GL_TEXTURE_WRAP_R,       GL_CLAMP_TO_EDGE);
-
-    GLint status;
-    char const* vsource[2] = { s_vertexES, s_vertexGL };
-    char const* fsource[2] = { s_fragmentES, s_fragmentGL };
-    const size_t index = GLES30_HEADERS ? 0 : 1;
-
-    mVertexShader = glCreateShader(GL_VERTEX_SHADER);
-    glShaderSource(mVertexShader, 1, vsource + index, nullptr);
-    glCompileShader(mVertexShader);
-    glGetShaderiv(mVertexShader, GL_COMPILE_STATUS, &status);
-    assert_invariant(status == GL_TRUE);
-
-    mFragmentShader = glCreateShader(GL_FRAGMENT_SHADER);
-    glShaderSource(mFragmentShader, 1, fsource + index, nullptr);
-    glCompileShader(mFragmentShader);
-    glGetShaderiv(mFragmentShader, GL_COMPILE_STATUS, &status);
-    assert_invariant(status == GL_TRUE);
-
-    mProgram = glCreateProgram();
-    glAttachShader(mProgram, mVertexShader);
-    glAttachShader(mProgram, mFragmentShader);
-    glLinkProgram(mProgram);
-    glGetProgramiv(mProgram, GL_LINK_STATUS, &status);
-    assert_invariant(status == GL_TRUE);
-
-    glUseProgram(mProgram);
-    GLint loc = glGetUniformLocation(mProgram, "sampler");
-    GLuint tmu = 0;
-    glUniform1i(loc, tmu);
-
-    glGenFramebuffers(1, &mFBO);
-
-    CHECK_GL_ERROR(utils::slog.e)
-}
-
-void OpenGLBlitter::terminate() noexcept {
-    glDeleteSamplers(1, &mSampler);
-    glDetachShader(mProgram, mVertexShader);
-    glDetachShader(mProgram, mFragmentShader);
-    glDeleteShader(mVertexShader);
-    glDeleteShader(mFragmentShader);
-    glDeleteProgram(mProgram);
-    glDeleteFramebuffers(1, &mFBO);
-}
-
-void OpenGLBlitter::blit(GLuint srcTextureExternal, GLuint dstTexture2d, GLuint w, GLuint h) noexcept {
-    const float2 vtx[3] = {{ -1.0f,  3.0f },
-                           { -1.0f, -1.0f },
-                           {  3.0f, -1.0f }};
-
-    // we're using tmu 0 as the source texture
-    GLuint tmu = 0;
-
-    // source texture
-    glBindSampler(tmu, mSampler);
-    glBindTexture(GL_TEXTURE_EXTERNAL_OES, srcTextureExternal);
-    CHECK_GL_ERROR(utils::slog.e)
-
-    // destination texture
-    glBindFramebuffer(GL_FRAMEBUFFER, mFBO);
-    glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, dstTexture2d, 0);
-    CHECK_GL_ERROR(utils::slog.e)
-    CHECK_GL_FRAMEBUFFER_STATUS(utils::slog.e, GL_FRAMEBUFFER)
-
-    // geometry
-    glBindBuffer(GL_ARRAY_BUFFER, 0);
-    glEnableVertexAttribArray(0);
-    glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, 0, vtx);
-
-    // blit...
-    glViewport(0, 0, w, h);
-    glUseProgram(mProgram);
-    glDrawArrays(GL_TRIANGLES, 0, 3);
-
-    CHECK_GL_ERROR(utils::slog.e)
-}
-
-void OpenGLBlitter::State::save() noexcept {
-    mHasState = true;
-    // TODO: technically we should also save glVertexAttribPointer
-    GLuint tmu = 0;
-    glGetIntegerv(GL_DRAW_FRAMEBUFFER_BINDING, &framebuffer);
-    glGetIntegerv(GL_ELEMENT_ARRAY_BUFFER_BINDING, &array);
-    glGetIntegerv(GL_CURRENT_PROGRAM, &program);
-    glGetIntegerv(GL_VIEWPORT, viewport);
-    glGetIntegerv(GL_COLOR_WRITEMASK, writeMask);
-    scissorTest = glIsEnabled(GL_SCISSOR_TEST);
-    stencilTest = glIsEnabled(GL_STENCIL_TEST);
-    cullFace = glIsEnabled(GL_CULL_FACE);
-    glGetVertexAttribiv(0, GL_VERTEX_ATTRIB_ARRAY_ENABLED, &vertexAttrib);
-
-    // save the current active texture first
-    glGetIntegerv(GL_ACTIVE_TEXTURE, &activeTexture);
-
-    // we're using tmu 0 as the source texture
-    glActiveTexture(GL_TEXTURE0 + tmu);
-
-    // save what depends on glActiveTexture
-    glGetIntegerv(GL_SAMPLER_BINDING, &sampler);
-    glGetIntegerv(GL_TEXTURE_BINDING_2D, &texture);
-
-    /*
-     * Set the state
-     */
-
-    // we're using tmu 0 as the source texture
-    glDisable(GL_SCISSOR_TEST);
-    glDisable(GL_STENCIL_TEST);
-    glDisable(GL_CULL_FACE);
-    glColorMask(GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE);
-    CHECK_GL_ERROR(utils::slog.e)
-}
-
-void OpenGLBlitter::State::restore() noexcept {
-    GLuint tmu = 0;
-    glColorMask(
-            (GLboolean)writeMask[0],
-            (GLboolean)writeMask[1],
-            (GLboolean)writeMask[2],
-            (GLboolean)writeMask[3]);
-    if (cullFace) {
-        glEnable(GL_CULL_FACE);
-    }
-    if (stencilTest) {
-        glEnable(GL_STENCIL_TEST);
-    }
-    if (scissorTest) {
-        glEnable(GL_SCISSOR_TEST);
-    }
-    glViewport(viewport[0], viewport[1], viewport[2], viewport[3]);
-    glUseProgram(static_cast<GLuint>(program));
-    glBindBuffer(GL_ARRAY_BUFFER, static_cast<GLuint>(array));
-    glBindFramebuffer(GL_FRAMEBUFFER, static_cast<GLuint>(framebuffer));
-    if (!vertexAttrib) {
-        glDisableVertexAttribArray(0);
-    }
-
-    glBindTexture(GL_TEXTURE_2D, static_cast<GLuint>(texture));
-    glBindSampler(tmu, static_cast<GLuint>(sampler));
-    glActiveTexture(static_cast<GLenum>(activeTexture));
-    CHECK_GL_ERROR(utils::slog.e)
-}
-
-} // namespace filament

filament/backend/src/opengl/OpenGLBlitter.h

@@ -1,67 +0,0 @@
-/*
- * Copyright (C) 2017 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_DRIVER_OPENGLBLITTER_H
-#define TNT_FILAMENT_DRIVER_OPENGLBLITTER_H
-
-#include <utils/compiler.h>
-#include "gl_headers.h"
-
-namespace filament {
-
-class OpenGLContext;
-
-class OpenGLBlitter {
-public:
-    explicit OpenGLBlitter(OpenGLContext& context) noexcept : mContext(context) {}
-
-    void init() noexcept;
-    void terminate() noexcept;
-
-    void blit(GLuint srcTextureExternal, GLuint dstTexture2d, GLuint w, GLuint h) noexcept;
-
-    class State {
-        bool mHasState = false;
-        GLint activeTexture, sampler, texture, framebuffer, array, vertexAttrib, program;
-        GLboolean stencilTest, scissorTest, cullFace;
-        GLint viewport[4], writeMask[4];
-        void save() noexcept;
-        void restore() noexcept;
-    public:
-        void setup() noexcept {
-            if (UTILS_UNLIKELY(!mHasState)) {
-                save();
-            }
-        }
-        ~State() noexcept {
-            if (UTILS_UNLIKELY(mHasState)) {
-                restore();
-            }
-        }
-    };
-
-private:
-    UTILS_UNUSED OpenGLContext& mContext;
-    GLuint mSampler{};
-    GLuint mVertexShader{};
-    GLuint mFragmentShader{};
-    GLuint mProgram{};
-    GLuint mFBO{};
-};
-
-} // namespace filament
-
-#endif // TNT_FILAMENT_DRIVER_OPENGLBLITTER_H

filament/backend/src/opengl/OpenGLContext.cpp

@@ -19,122 +19,153 @@
 // change to true to display all GL extensions in the console on start-up
 #define DEBUG_PRINT_EXTENSIONS false
 
-
 using namespace utils;
 
-namespace filament {
+namespace filament::backend {
 
-using namespace backend;
+bool OpenGLContext::queryOpenGLVersion(GLint* major, GLint* minor) noexcept {
+    if constexpr (BACKEND_OPENGL_VERSION == BACKEND_OPENGL_VERSION_GLES) {
+        char const* version = (char const*)glGetString(GL_VERSION);
+        // This works on all versions of GLES
+        int n = version ? sscanf(version, "OpenGL ES %d.%d", major, minor) : 0;
+        return n == 2;
+    } else if constexpr (BACKEND_OPENGL_VERSION == BACKEND_OPENGL_VERSION_GL) {
+        // OpenGL version
+        glGetIntegerv(GL_MAJOR_VERSION, major);
+        glGetIntegerv(GL_MINOR_VERSION, minor);
+        return (glGetError() == GL_NO_ERROR);
+    }
+}
 
 OpenGLContext::OpenGLContext() noexcept {
     state.vao.p = &mDefaultVAO;
-    state.enables.caps.set(getIndexForCap(GL_DITHER));
 
-    UTILS_UNUSED char const* const vendor   = (char const*) glGetString(GL_VENDOR);
-    UTILS_UNUSED char const* const renderer = (char const*) glGetString(GL_RENDERER);
-    UTILS_UNUSED char const* const version  = (char const*) glGetString(GL_VERSION);
-    UTILS_UNUSED char const* const shader   = (char const*) glGetString(GL_SHADING_LANGUAGE_VERSION);
+    // There query work with all GL/GLES versions!
+    state.vendor   = (char const*)glGetString(GL_VENDOR);
+    state.renderer = (char const*)glGetString(GL_RENDERER);
+    state.version  = (char const*)glGetString(GL_VERSION);
+    state.shader   = (char const*)glGetString(GL_SHADING_LANGUAGE_VERSION);
 
-    slog.v << "[" << vendor << "], [" << renderer << "], [" << version << "], [" << shader << "]" << io::endl;
+    slog.v << "[" << state.vendor << "], [" << state.renderer << "], "
+              "[" << state.version << "], [" << state.shader << "]" << io::endl;
 
-    // OpenGL (ES) version
-    GLint major = 0;
-    GLint minor = 0;
-    glGetIntegerv(GL_MAJOR_VERSION, &major);
-    glGetIntegerv(GL_MINOR_VERSION, &minor);
+    /*
+     * Figure out GL / GLES version and available features
+     */
 
-    // Figure out if we have the extension we need
-    GLint n = 0;
-    glGetIntegerv(GL_NUM_EXTENSIONS, &n);
-    ExtentionSet exts;
-    for (GLint i = 0; i < n; i++) {
-        const char * const extension = (const char*)glGetStringi(GL_EXTENSIONS, (GLuint)i);
-        exts.insert(StaticString::make(extension, strlen(extension)));
-        if (DEBUG_PRINT_EXTENSIONS) {
-            slog.d << extension << io::endl;
+    queryOpenGLVersion(&state.major, &state.minor);
+
+    if constexpr (BACKEND_OPENGL_VERSION == BACKEND_OPENGL_VERSION_GLES) {
+        // This works on all versions of GLES
+        if (state.major == 3 && state.minor >= 0) {
+            mShaderModel = ShaderModel::GL_ES_30;
         }
-    }
-    ShaderModel shaderModel = ShaderModel::UNKNOWN;
-    if (GLES30_HEADERS) {
-        if (major == 3 && minor >= 0) {
-            shaderModel = ShaderModel::GL_ES_30;
-        }
-        if (major == 3 && minor >= 1) {
+        if (state.major == 3 && state.minor >= 1) {
             features.multisample_texture = true;
         }
-        initExtensionsGLES(major, minor, exts);
-    } else if (GL41_HEADERS) {
-        if (major == 4 && minor >= 1) {
-            shaderModel = ShaderModel::GL_CORE_41;
+        initExtensionsGLES();
+    } else if constexpr (BACKEND_OPENGL_VERSION == BACKEND_OPENGL_VERSION_GL) {
+        // OpenGL version
+        if (state.major == 4 && state.minor >= 1) {
+            mShaderModel = ShaderModel::GL_CORE_41;
         }
-        initExtensionsGL(major, minor, exts);
         features.multisample_texture = true;
         // feedback loops are allowed on GL desktop as long as writes are disabled
         bugs.allow_read_only_ancillary_feedback_loop = true;
+        initExtensionsGL();
     }
-    assert_invariant(shaderModel != ShaderModel::UNKNOWN);
-    mShaderModel = shaderModel;
 
-    // Figure out which driver bugs we need to workaround
-    if (strstr(renderer, "Adreno")) {
-        bugs.invalidate_end_only_if_invalidate_start = true;
+    assert_invariant(mShaderModel != ShaderModel::UNKNOWN);
 
-        // On Adreno (As of 3/20) timer query seem to return the CPU time, not the GPU time.
-        bugs.dont_use_timer_query = true;
+    /*
+     * Figure out which driver bugs we need to workaround
+     */
 
-        // Blits to texture arrays are failing
-        //   This bug continues to reproduce, though at times we've seen it appear to "go away". The
-        //   standalone sample app that was written to show this problem still reproduces.
-        //   The working hypthesis is that some other state affects this behavior.
-        bugs.disable_sidecar_blit_into_texture_array = true;
+    const bool isAngle = strstr(state.renderer, "ANGLE");
+    if (!isAngle) {
+        if (strstr(state.renderer, "Adreno")) {
+            // Qualcomm GPU
+            bugs.invalidate_end_only_if_invalidate_start = true;
 
-        // early exit condition is flattened in EASU code
-        bugs.split_easu = true;
-
-        int maj, min, driverMajor, driverMinor;
-        int c = sscanf(version, "OpenGL ES %d.%d V@%d.%d", // NOLINT(cert-err34-c)
-                &maj, &min, &driverMajor, &driverMinor);
-        if (c == 4) {
-            // workarounds based on version here.
-            // notes:
-            //  bugs.invalidate_end_only_if_invalidate_start
-            //      - appeared at least in "OpenGL ES 3.2 V@0490.0 (GIT@85da404, I46ff5fc46f, 1606794520) (Date:11/30/20)"
-            //      - wasn't present in    "OpenGL ES 3.2 V@0490.0 (GIT@0905e9f, Ia11ce2d146, 1599072951) (Date:09/02/20)"
-            //      - has been confirmed fixed in V@570.1 by Qualcomm
-            if (driverMajor < 490 || driverMajor > 570 || (driverMajor == 570 && driverMinor >= 1)) {
-                bugs.invalidate_end_only_if_invalidate_start = false;
-            }
-        }
-
-        // qualcomm seems to have no problem with this (which is good for us)
-        bugs.allow_read_only_ancillary_feedback_loop = true;
-    } else if (strstr(renderer, "Mali")) {
-        bugs.vao_doesnt_store_element_array_buffer_binding = true;
-        if (strstr(renderer, "Mali-T")) {
-            bugs.disable_glFlush = true;
-            bugs.disable_shared_context_draws = true;
-            bugs.texture_external_needs_rebind = true;
-            // We have not verified that timer queries work on Mali-T, so we disable to be safe.
+            // On Adreno (As of 3/20) timer query seem to return the CPU time, not the GPU time.
             bugs.dont_use_timer_query = true;
-        }
-        if (strstr(renderer, "Mali-G")) {
-            // note: We have verified that timer queries work well at least on some Mali-G.
-        }
 
-        // Mali seems to have no problem with this (which is good for us)
-        bugs.allow_read_only_ancillary_feedback_loop = true;
-    } else if (strstr(renderer, "Intel")) {
-        bugs.vao_doesnt_store_element_array_buffer_binding = true;
-    } else if (strstr(renderer, "PowerVR")) {
-    } else if (strstr(renderer, "Apple")) {
-    } else if (strstr(renderer, "Tegra") || strstr(renderer, "GeForce") || strstr(renderer, "NV")) {
-    } else if (strstr(renderer, "Vivante")) {
-    } else if (strstr(renderer, "AMD") || strstr(renderer, "ATI")) {
-    } else if (strstr(renderer, "Mozilla")) {
-        bugs.disable_invalidate_framebuffer = true;
+            // Blits to texture arrays are failing
+            //   This bug continues to reproduce, though at times we've seen it appear to "go away".
+            //   The standalone sample app that was written to show this problem still reproduces.
+            //   The working hypthesis is that some other state affects this behavior.
+            bugs.disable_sidecar_blit_into_texture_array = true;
+
+            // early exit condition is flattened in EASU code
+            bugs.split_easu = true;
+
+            int maj, min, driverMajor, driverMinor;
+            int c = sscanf(state.version, "OpenGL ES %d.%d V@%d.%d", // NOLINT(cert-err34-c)
+                    &maj, &min, &driverMajor, &driverMinor);
+            if (c == 4) {
+                // workarounds based on version here.
+                // notes:
+                //  bugs.invalidate_end_only_if_invalidate_start
+                //  - appeared at least in
+                //      "OpenGL ES 3.2 V@0490.0 (GIT@85da404, I46ff5fc46f, 1606794520) (Date:11/30/20)"
+                //  - wasn't present in
+                //      "OpenGL ES 3.2 V@0490.0 (GIT@0905e9f, Ia11ce2d146, 1599072951) (Date:09/02/20)"
+                //  - has been confirmed fixed in V@570.1 by Qualcomm
+                if (driverMajor < 490 || driverMajor > 570 ||
+                    (driverMajor == 570 && driverMinor >= 1)) {
+                    bugs.invalidate_end_only_if_invalidate_start = false;
+                }
+            }
+
+            // qualcomm seems to have no problem with this (which is good for us)
+            bugs.allow_read_only_ancillary_feedback_loop = true;
+        } else if (strstr(state.renderer, "Mali")) {
+            // ARM GPU
+            bugs.vao_doesnt_store_element_array_buffer_binding = true;
+            if (strstr(state.renderer, "Mali-T")) {
+                bugs.disable_glFlush = true;
+                bugs.disable_shared_context_draws = true;
+                bugs.texture_external_needs_rebind = true;
+                // We have not verified that timer queries work on Mali-T, so we disable to be safe.
+                bugs.dont_use_timer_query = true;
+            }
+            if (strstr(state.renderer, "Mali-G")) {
+                // note: We have verified that timer queries work well at least on some Mali-G.
+            }
+            // Mali seems to have no problem with this (which is good for us)
+            bugs.allow_read_only_ancillary_feedback_loop = true;
+        } else if (strstr(state.renderer, "Intel")) {
+            // Intel GPU
+            bugs.vao_doesnt_store_element_array_buffer_binding = true;
+        } else if (strstr(state.renderer, "PowerVR")) {
+            // PowerVR GPU
+        } else if (strstr(state.renderer, "Apple")) {
+            // Apple GPU
+        } else if (strstr(state.renderer, "Tegra") ||
+                   strstr(state.renderer, "GeForce") ||
+                   strstr(state.renderer, "NV")) {
+            // NVIDIA GPU
+        } else if (strstr(state.renderer, "Vivante")) {
+            // Vivante GPU
+        } else if (strstr(state.renderer, "AMD") ||
+                   strstr(state.renderer, "ATI")) {
+            // AMD/ATI GPU
+        } else if (strstr(state.renderer, "Mozilla")) {
+            bugs.disable_invalidate_framebuffer = true;
+        }
+    } else {
+        // When running under ANGLE, it's a different set of workaround that we need.
+        if (strstr(state.renderer, "Adreno")) {
+            // Qualcomm GPU
+            // early exit condition is flattened in EASU code
+            // (that should be regardless of ANGLE, but we should double check)
+            bugs.split_easu = true;
+        }
+        // TODO: see if we could use `bugs.allow_read_only_ancillary_feedback_loop = true`
     }
 
     slog.v << "Active workarounds: " << '\n';
+    UTILS_NOUNROLL
     for (auto [enabled, name, _] : mBugDatabase) {
         if (enabled) {
             slog.v << name << '\n';
@@ -186,7 +217,7 @@ OpenGLContext::OpenGLContext() noexcept {
 
     // Point sprite size and seamless cubemap filtering are disabled by default in desktop GL.
     // In OpenGL ES, these flags do not exist because they are always on.
-#if GL41_HEADERS
+#if BACKEND_OPENGL_VERSION == BACKEND_OPENGL_VERSION_GL
     enable(GL_PROGRAM_POINT_SIZE);
 #endif
 
@@ -219,50 +250,27 @@ OpenGLContext::OpenGLContext() noexcept {
     if (ext.KHR_debug) {
         auto cb = [](GLenum source, GLenum type, GLuint id, GLenum severity, GLsizei length,
                 const GLchar* message, const void *userParam) {
-            io::ostream* stream = nullptr;
+            io::ostream* stream = &slog.i;
             switch (severity) {
-                case GL_DEBUG_SEVERITY_HIGH:
-                    stream = &slog.e;
-                    break;
-                case GL_DEBUG_SEVERITY_MEDIUM:
-                    stream = &slog.w;
-                    break;
-                case GL_DEBUG_SEVERITY_LOW:
-                    stream = &slog.d;
-                    break;
+                case GL_DEBUG_SEVERITY_HIGH:    stream = &slog.e;   break;
+                case GL_DEBUG_SEVERITY_MEDIUM:  stream = &slog.w;   break;
+                case GL_DEBUG_SEVERITY_LOW:     stream = &slog.d;   break;
                 case GL_DEBUG_SEVERITY_NOTIFICATION:
-                default:
-                    stream = &slog.i;
-                    break;
+                default: break;
             }
             io::ostream& out = *stream;
-            out << "KHR_debug ";
+            const char* level = ": ";
             switch (type) {
-                case GL_DEBUG_TYPE_ERROR:
-                    out << "ERROR";
-                    break;
-                case GL_DEBUG_TYPE_DEPRECATED_BEHAVIOR:
-                    out << "DEPRECATED_BEHAVIOR";
-                    break;
-                case GL_DEBUG_TYPE_UNDEFINED_BEHAVIOR:
-                    out << "UNDEFINED_BEHAVIOR";
-                    break;
-                case GL_DEBUG_TYPE_PORTABILITY:
-                    out << "PORTABILITY";
-                    break;
-                case GL_DEBUG_TYPE_PERFORMANCE:
-                    out << "PERFORMANCE";
-                    break;
-                case GL_DEBUG_TYPE_OTHER:
-                    out << "OTHER";
-                    break;
-                case GL_DEBUG_TYPE_MARKER:
-                    out << "MARKER";
-                    break;
-                default:
-                    break;
+                case GL_DEBUG_TYPE_ERROR:               level = "ERROR: ";               break;
+                case GL_DEBUG_TYPE_DEPRECATED_BEHAVIOR: level = "DEPRECATED_BEHAVIOR: "; break;
+                case GL_DEBUG_TYPE_UNDEFINED_BEHAVIOR:  level = "UNDEFINED_BEHAVIOR: ";  break;
+                case GL_DEBUG_TYPE_PORTABILITY:         level = "PORTABILITY: ";         break;
+                case GL_DEBUG_TYPE_PERFORMANCE:         level = "PERFORMANCE: ";         break;
+                case GL_DEBUG_TYPE_OTHER:               level = "OTHER: ";               break;
+                case GL_DEBUG_TYPE_MARKER:              level = "MARKER: ";              break;
+                default: break;
             }
-            out << ": " << message << io::endl;
+            out << "KHR_debug " << level << message << io::endl;
         };
         glEnable(GL_DEBUG_OUTPUT);
         glEnable(GL_DEBUG_OUTPUT_SYNCHRONOUS);
@@ -277,60 +285,81 @@ OpenGLContext::OpenGLContext() noexcept {
 #endif
 }
 
-UTILS_NOINLINE
-bool OpenGLContext::hasExtension(ExtentionSet const& map, utils::StaticString ext) noexcept {
-    return map.find(ext) != map.end();
-}
+void OpenGLContext::initExtensionsGLES() noexcept {
+    const char * const extensions = (const char*)glGetString(GL_EXTENSIONS);
+    GLUtils::unordered_string_set exts = GLUtils::split(extensions);
+    if constexpr (DEBUG_PRINT_EXTENSIONS) {
+        for (auto extension: exts) {
+            slog.d << "\"" << std::string_view(extension) << "\"\n";
+        }
+        flush(slog.d);
+    }
 
-void OpenGLContext::initExtensionsGLES(GLint major, GLint minor, ExtentionSet const& exts) {
     // figure out and initialize the extensions we need
-    ext.APPLE_color_buffer_packed_float = hasExtension(exts, "GL_APPLE_color_buffer_packed_float");
-    ext.EXT_clip_control = hasExtension(exts, "GL_EXT_clip_control");
-    ext.EXT_color_buffer_float = hasExtension(exts, "GL_EXT_color_buffer_float");
-    ext.EXT_color_buffer_half_float = hasExtension(exts, "GL_EXT_color_buffer_half_float");
-    ext.EXT_debug_marker = hasExtension(exts, "GL_EXT_debug_marker");
-    ext.EXT_disjoint_timer_query = hasExtension(exts, "GL_EXT_disjoint_timer_query");
-    ext.EXT_multisampled_render_to_texture = hasExtension(exts, "GL_EXT_multisampled_render_to_texture");
-    ext.EXT_multisampled_render_to_texture2 = hasExtension(exts, "GL_EXT_multisampled_render_to_texture2");
-    ext.EXT_shader_framebuffer_fetch = hasExtension(exts, "GL_EXT_shader_framebuffer_fetch");
+    using namespace std::literals;
+    ext.APPLE_color_buffer_packed_float = exts.has("GL_APPLE_color_buffer_packed_float"sv);
+    ext.EXT_clip_control = exts.has("GL_EXT_clip_control"sv);
+    ext.EXT_color_buffer_float = exts.has("GL_EXT_color_buffer_float"sv);
+    ext.EXT_color_buffer_half_float = exts.has("GL_EXT_color_buffer_half_float"sv);
+    ext.EXT_debug_marker = exts.has("GL_EXT_debug_marker"sv);
+    ext.EXT_disjoint_timer_query = exts.has("GL_EXT_disjoint_timer_query"sv);
+    ext.EXT_multisampled_render_to_texture = exts.has("GL_EXT_multisampled_render_to_texture"sv);
+    ext.EXT_multisampled_render_to_texture2 = exts.has("GL_EXT_multisampled_render_to_texture2"sv);
+    ext.EXT_shader_framebuffer_fetch = exts.has("GL_EXT_shader_framebuffer_fetch"sv);
     ext.EXT_texture_compression_etc2 = true;
-    ext.EXT_texture_filter_anisotropic = hasExtension(exts, "GL_EXT_texture_filter_anisotropic");
-    ext.GOOGLE_cpp_style_line_directive = hasExtension(exts, "GL_GOOGLE_cpp_style_line_directive");
-    ext.KHR_debug = hasExtension(exts, "GL_KHR_debug");
-    ext.OES_EGL_image_external_essl3 = hasExtension(exts, "GL_OES_EGL_image_external_essl3");
-    ext.QCOM_tiled_rendering = hasExtension(exts, "GL_QCOM_tiled_rendering");
-    ext.EXT_texture_compression_s3tc = hasExtension(exts, "GL_EXT_texture_compression_s3tc");
-    ext.EXT_texture_compression_s3tc_srgb = hasExtension(exts, "GL_EXT_texture_compression_s3tc_srgb");
-    ext.WEBGL_compressed_texture_s3tc = hasExtension(exts, "WEBGL_compressed_texture_s3tc");
-    ext.WEBGL_compressed_texture_s3tc_srgb = hasExtension(exts, "WEBGL_compressed_texture_s3tc_srgb");
-    ext.WEBGL_compressed_texture_etc = hasExtension(exts, "WEBGL_compressed_texture_etc");
+    ext.EXT_texture_filter_anisotropic = exts.has("GL_EXT_texture_filter_anisotropic"sv);
+    ext.GOOGLE_cpp_style_line_directive = exts.has("GL_GOOGLE_cpp_style_line_directive"sv);
+    ext.KHR_debug = exts.has("GL_KHR_debug"sv);
+    ext.OES_EGL_image_external_essl3 = exts.has("GL_OES_EGL_image_external_essl3"sv);
+    ext.QCOM_tiled_rendering = exts.has("GL_QCOM_tiled_rendering"sv);
+    ext.EXT_texture_compression_s3tc = exts.has("GL_EXT_texture_compression_s3tc"sv);
+    ext.EXT_texture_compression_s3tc_srgb = exts.has("GL_EXT_texture_compression_s3tc_srgb"sv);
+    ext.WEBGL_compressed_texture_s3tc = exts.has("WEBGL_compressed_texture_s3tc"sv);
+    ext.WEBGL_compressed_texture_s3tc_srgb = exts.has("WEBGL_compressed_texture_s3tc_srgb"sv);
+    ext.WEBGL_compressed_texture_etc = exts.has("WEBGL_compressed_texture_etc"sv);
     // ES 3.2 implies EXT_color_buffer_float
-    if (major >= 3 && minor >= 2) {
+    if (state.major >= 3 && state.minor >= 2) {
         ext.EXT_color_buffer_float = true;
     }
 }
 
-void OpenGLContext::initExtensionsGL(GLint major, GLint minor, ExtentionSet const& exts) {
+void OpenGLContext::initExtensionsGL() noexcept {
+    GLUtils::unordered_string_set exts;
+    GLint n = 0;
+    glGetIntegerv(GL_NUM_EXTENSIONS, &n);
+    for (GLint i = 0; i < n; i++) {
+        exts.emplace((const char*)glGetStringi(GL_EXTENSIONS, (GLuint)i));
+    }
+    if constexpr (DEBUG_PRINT_EXTENSIONS) {
+        for (auto extension: exts) {
+            slog.d << "\"" << std::string_view(extension) << "\"\n";
+        }
+        flush(slog.d);
+    }
+
+    using namespace std::literals;
+    auto major = state.major;
+    auto minor = state.minor;
     ext.APPLE_color_buffer_packed_float = true;  // Assumes core profile.
-    ext.ARB_shading_language_packing = hasExtension(exts, "GL_ARB_shading_language_packing") || (major == 4 && minor >= 2);
-    ext.EXT_clip_control = hasExtension(exts, "GL_ARB_clip_control") || (major == 4 && minor >= 5);
+    ext.ARB_shading_language_packing = exts.has("GL_ARB_shading_language_packing"sv) || (major == 4 && minor >= 2);
+    ext.EXT_clip_control = exts.has("GL_ARB_clip_control"sv) || (major == 4 && minor >= 5);
     ext.EXT_color_buffer_float = true;  // Assumes core profile.
     ext.EXT_color_buffer_half_float = true;  // Assumes core profile.
-    ext.EXT_debug_marker = hasExtension(exts, "GL_EXT_debug_marker");
-    ext.EXT_shader_framebuffer_fetch = hasExtension(exts, "GL_EXT_shader_framebuffer_fetch");
-    ext.EXT_texture_compression_etc2 = hasExtension(exts, "GL_ARB_ES3_compatibility");
-    ext.EXT_texture_filter_anisotropic = hasExtension(exts, "GL_EXT_texture_filter_anisotropic");
-    ext.EXT_texture_sRGB = hasExtension(exts, "GL_EXT_texture_sRGB");
-    ext.GOOGLE_cpp_style_line_directive = hasExtension(exts, "GL_GOOGLE_cpp_style_line_directive");
+    ext.EXT_debug_marker = exts.has("GL_EXT_debug_marker"sv);
+    ext.EXT_shader_framebuffer_fetch = exts.has("GL_EXT_shader_framebuffer_fetch"sv);
+    ext.EXT_texture_compression_etc2 = exts.has("GL_ARB_ES3_compatibility"sv);
+    ext.EXT_texture_filter_anisotropic = exts.has("GL_EXT_texture_filter_anisotropic"sv);
+    ext.EXT_texture_sRGB = exts.has("GL_EXT_texture_sRGB"sv);
+    ext.GOOGLE_cpp_style_line_directive = exts.has("GL_GOOGLE_cpp_style_line_directive"sv);
     ext.KHR_debug = major >= 4 && minor >= 3;
-    ext.OES_EGL_image_external_essl3 = hasExtension(exts, "GL_OES_EGL_image_external_essl3");
-    ext.EXT_texture_compression_s3tc = hasExtension(exts, "GL_EXT_texture_compression_s3tc");
-    ext.EXT_texture_compression_s3tc_srgb = hasExtension(exts, "GL_EXT_texture_compression_s3tc_srgb");
+    ext.OES_EGL_image_external_essl3 = exts.has("GL_OES_EGL_image_external_essl3"sv);
+    ext.EXT_texture_compression_s3tc = exts.has("GL_EXT_texture_compression_s3tc"sv);
+    ext.EXT_texture_compression_s3tc_srgb = exts.has("GL_EXT_texture_compression_s3tc_srgb"sv);
 }
 
 void OpenGLContext::bindBuffer(GLenum target, GLuint buffer) noexcept {
-    size_t targetIndex = getIndexForBufferTarget(target);
     if (target == GL_ELEMENT_ARRAY_BUFFER) {
+        constexpr size_t targetIndex = getIndexForBufferTarget(GL_ELEMENT_ARRAY_BUFFER);
         // GL_ELEMENT_ARRAY_BUFFER is a special case, where the currently bound VAO remembers
         // the index buffer, unless there are no VAO bound (see: bindVertexArray)
         assert_invariant(state.vao.p);
@@ -343,6 +372,7 @@ void OpenGLContext::bindBuffer(GLenum target, GLuint buffer) noexcept {
             glBindBuffer(target, buffer);
         }
     } else {
+        size_t targetIndex = getIndexForBufferTarget(target);
         update_state(state.buffers.genericBinding[targetIndex], buffer, [&]() {
             glBindBuffer(target, buffer);
         });
@@ -350,33 +380,22 @@ void OpenGLContext::bindBuffer(GLenum target, GLuint buffer) noexcept {
 }
 
 void OpenGLContext::pixelStore(GLenum pname, GLint param) noexcept {
-    GLint* pcur = nullptr;
-    switch (pname) {
-        case GL_PACK_ROW_LENGTH:
-            pcur = &state.pack.row_length;
-            break;
-        case GL_PACK_SKIP_ROWS:
-            pcur = &state.pack.skip_row;
-            break;
-        case GL_PACK_SKIP_PIXELS:
-            pcur = &state.pack.skip_pixels;
-            break;
-        case GL_PACK_ALIGNMENT:
-            pcur = &state.pack.alignment;
-            break;
+    GLint* pcur;
 
-        case GL_UNPACK_ROW_LENGTH:
-            pcur = &state.unpack.row_length;
-            break;
-        case GL_UNPACK_ALIGNMENT:
-            pcur = &state.unpack.alignment;
-            break;
-        case GL_UNPACK_SKIP_PIXELS:
-            pcur = &state.unpack.skip_pixels;
-            break;
-        case GL_UNPACK_SKIP_ROWS:
-            pcur = &state.unpack.skip_row;
-            break;
+    // Note: GL_UNPACK_SKIP_PIXELS, GL_UNPACK_SKIP_ROWS and
+    //       GL_PACK_SKIP_PIXELS, GL_PACK_SKIP_ROWS
+    // are actually provided as conveniences to the programmer; they provide no functionality
+    // that cannot be duplicated at the call site (e.g. glTexImage2D or glReadPixels)
+
+    switch (pname) {
+        case GL_PACK_ALIGNMENT:     pcur = &state.pack.alignment;       break;
+        case GL_PACK_ROW_LENGTH:    pcur = &state.pack.row_length;      break;
+        case GL_PACK_SKIP_PIXELS:   pcur = &state.pack.skip_pixels;     break;  // convenience
+        case GL_PACK_SKIP_ROWS:     pcur = &state.pack.skip_row;        break;  // convenience
+        case GL_UNPACK_ALIGNMENT:   pcur = &state.unpack.alignment;     break;
+        case GL_UNPACK_ROW_LENGTH:  pcur = &state.unpack.row_length;    break;
+        case GL_UNPACK_SKIP_PIXELS: pcur = &state.unpack.skip_pixels;   break;  // convenience
+        case GL_UNPACK_SKIP_ROWS:   pcur = &state.unpack.skip_row;      break;  // convenience
         default:
             goto default_case;
     }
@@ -393,6 +412,7 @@ void OpenGLContext::unbindTexture(GLenum target, GLuint texture_id) noexcept {
     // no need unbind the texture from FBOs because we're not tracking that state (and there is
     // no need to).
     const size_t index = getIndexForTextureTarget(target);
+    UTILS_NOUNROLL
     for (GLuint unit = 0; unit < MAX_TEXTURE_UNIT_COUNT; unit++) {
         if (state.textures.units[unit].targets[index].texture_id == texture_id) {
             bindTexture(unit, target, (GLuint)0, index);
@@ -402,7 +422,7 @@ void OpenGLContext::unbindTexture(GLenum target, GLuint texture_id) noexcept {
 
 void OpenGLContext::unbindSampler(GLuint sampler) noexcept {
     // unbind this sampler from all the units it might be bound to
-#pragma nounroll    // clang generates >800B of code!!!
+    UTILS_NOUNROLL  // clang generates >800B of code!!!
     for (GLuint unit = 0; unit < MAX_TEXTURE_UNIT_COUNT; unit++) {
         if (state.textures.units[unit].sampler == sampler) {
             bindSampler(unit, 0);
@@ -415,7 +435,7 @@ void OpenGLContext::deleteBuffers(GLsizei n, const GLuint* buffers, GLenum targe
     // bindings of bound buffers are reset to 0
     const size_t targetIndex = getIndexForBufferTarget(target);
     auto& genericBuffer = state.buffers.genericBinding[targetIndex];
-    #pragma nounroll
+    UTILS_NOUNROLL
     for (GLsizei i = 0; i < n; ++i) {
         if (genericBuffer == buffers[i]) {
             genericBuffer = 0;
@@ -423,9 +443,9 @@ void OpenGLContext::deleteBuffers(GLsizei n, const GLuint* buffers, GLenum targe
     }
     if (target == GL_UNIFORM_BUFFER || target == GL_TRANSFORM_FEEDBACK_BUFFER) {
         auto& indexedBuffer = state.buffers.targets[targetIndex];
-        #pragma nounroll // clang generates >1 KiB of code!!
+        UTILS_NOUNROLL // clang generates >1 KiB of code!!
         for (GLsizei i = 0; i < n; ++i) {
-            #pragma nounroll
+            UTILS_NOUNROLL
             for (auto& buffer : indexedBuffer.buffers) {
                 if (buffer.name == buffers[i]) {
                     buffer.name = 0;

filament/backend/src/opengl/OpenGLContext.h

@@ -30,47 +30,46 @@
 #include <set>
 #include <utility>
 
-namespace filament {
+namespace filament::backend {
 
 class OpenGLContext {
 public:
-    static constexpr const size_t MAX_TEXTURE_UNIT_COUNT = backend::MAX_SAMPLER_COUNT;
+    static constexpr const size_t MAX_TEXTURE_UNIT_COUNT = MAX_SAMPLER_COUNT;
     static constexpr const size_t MAX_BUFFER_BINDINGS = 32;
     typedef math::details::TVec4<GLint> vec4gli;
     typedef math::details::TVec2<GLclampf> vec2glf;
 
-    // TODO: the footprint of this structure can be reduced. We need only 1 bit for index type, 16
-    // bits for vertexAttribArray. We can also use fewer bits for vertexBufferVersion, although
-    // this will require a corollary update in OpenGLDriver::setVertexBufferObject().
     struct RenderPrimitive {
-        GLuint vao = 0;
-        GLenum indicesType = GL_UNSIGNED_INT;
-        GLuint elementArray = 0;
-        utils::bitset32 vertexAttribArray;
+        static_assert(MAX_VERTEX_ATTRIBUTE_COUNT <= 16);
+
+        GLuint vao = 0;                                         // 4
+        GLuint elementArray = 0;                                // 4
+        utils::bitset<uint16_t> vertexAttribArray;              // 2
+
+        // If this version number does not match vertexBufferWithObjects->bufferObjectsVersion,
+        // then the VAO needs to be updated.
+        uint8_t vertexBufferVersion = 0;                        // 1
+        uint8_t indicesSize = 0;                                // 1
 
         // The optional 32-bit handle to a GLVertexBuffer is necessary only if the referenced
         // VertexBuffer supports buffer objects. If this is zero, then the VBO handles array is
         // immutable.
-        backend::Handle<backend::HwVertexBuffer> vertexBufferWithObjects = {};
+        Handle<HwVertexBuffer> vertexBufferWithObjects = {};    // 4
 
-        // If this version number does not match vertexBufferWithObjects->bufferObjectsVersion,
-        // then the VAO needs to be updated.
-        uint8_t vertexBufferVersion = 0;
+        GLenum getIndicesType() const noexcept {
+            return indicesSize == 4 ? GL_UNSIGNED_INT : GL_UNSIGNED_SHORT;
+        }
     } gl;
 
-    OpenGLContext() noexcept;
+    static bool queryOpenGLVersion(GLint* major, GLint* minor) noexcept;
 
-    // this is chosen to minimize code size
-    using ExtentionSet = std::set<utils::StaticString>;
-    static bool hasExtension(ExtentionSet const& exts, utils::StaticString ext) noexcept;
-    void initExtensionsGLES(GLint major, GLint minor, ExtentionSet const& extensionsMap);
-    void initExtensionsGL(GLint major, GLint minor, ExtentionSet const& extensionsMap);
+    OpenGLContext() noexcept;
 
     constexpr static inline size_t getIndexForTextureTarget(GLuint target) noexcept;
     constexpr        inline size_t getIndexForCap(GLenum cap) noexcept;
     constexpr static inline size_t getIndexForBufferTarget(GLenum target) noexcept;
 
-    backend::ShaderModel getShaderModel() const noexcept { return mShaderModel; }
+    ShaderModel getShaderModel() const noexcept { return mShaderModel; }
 
 
     inline void useProgram(GLuint program) noexcept;
@@ -105,7 +104,7 @@ public:
     inline void polygonOffset(GLfloat factor, GLfloat units) noexcept;
     inline void beginQuery(GLenum target, GLuint query) noexcept;
     inline void endQuery(GLenum target) noexcept;
-    inline GLuint getQuery(GLenum target) noexcept;
+    inline GLuint getQuery(GLenum target) const noexcept;
 
     inline void setScissor(GLint left, GLint bottom, GLsizei width, GLsizei height) noexcept;
     inline void viewport(GLint left, GLint bottom, GLsizei width, GLsizei height) noexcept;
@@ -205,6 +204,19 @@ public:
         bool allow_read_only_ancillary_feedback_loop = false;
     } bugs;
 
+    // state getters -- as needed.
+    vec4gli const& getViewport() const { return state.window.viewport; }
+
+    // function to handle state changes we don't control
+    void updateTexImage(GLenum target, GLuint id) noexcept {
+        const size_t index = getIndexForTextureTarget(target);
+        state.textures.units[state.textures.active].targets[index].texture_id = id;
+    }
+    void resetProgram() noexcept { state.program.use = 0; }
+
+private:
+    ShaderModel mShaderModel = ShaderModel::UNKNOWN;
+
     const std::array<std::tuple<bool const&, char const*, char const*>, sizeof(bugs)> mBugDatabase{{
             {   bugs.disable_glFlush,
                     "disable_glFlush",
@@ -244,22 +256,16 @@ public:
                     ""},
     }};
 
-    // state getters -- as needed.
-    GLuint getDrawFbo() const noexcept { return state.draw_fbo; }
-    vec4gli const& getViewport() const { return state.window.viewport; }
-
-    // function to handle state changes we don't control
-    void updateTexImage(GLenum target, GLuint id) noexcept {
-        const size_t index = getIndexForTextureTarget(target);
-        state.textures.units[state.textures.active].targets[index].texture_id = id;
-    }
-    void resetProgram() noexcept { state.program.use = 0; }
-
-private:
-    backend::ShaderModel mShaderModel;
-
     // Try to keep the State structure sorted by data-access patterns
     struct State {
+        GLint major = 0;
+        GLint minor = 0;
+
+        char const* vendor = nullptr;
+        char const* renderer = nullptr;
+        char const* version = nullptr;
+        char const* shader = nullptr;
+
         GLuint draw_fbo = 0;
         GLuint read_fbo = 0;
 
@@ -345,6 +351,10 @@ private:
 
     RenderPrimitive mDefaultVAO;
 
+    // this is chosen to minimize code size
+    void initExtensionsGLES() noexcept;
+    void initExtensionsGL() noexcept;
+
     template <typename T, typename F>
     static inline void update_state(T& state, T const& expected, F functor, bool force = false) noexcept {
         if (UTILS_UNLIKELY(force || state != expected)) {
@@ -390,7 +400,7 @@ constexpr size_t OpenGLContext::getIndexForCap(GLenum cap) noexcept { //NOLINT
 #ifdef GL_ARB_seamless_cube_map
         case GL_TEXTURE_CUBE_MAP_SEAMLESS:      index = 11; break;
 #endif
-#if GL41_HEADERS
+#if BACKEND_OPENGL_VERSION == BACKEND_OPENGL_VERSION_GL
         case GL_PROGRAM_POINT_SIZE:             index = 12; break;
 #endif
         default: index = 13; break; // should never happen
@@ -661,7 +671,7 @@ void OpenGLContext::endQuery(GLenum target) noexcept {
     glEndQuery(target);
 }
 
-GLuint OpenGLContext::getQuery(GLenum target) noexcept {
+GLuint OpenGLContext::getQuery(GLenum target) const noexcept {
     switch (target) {
         case GL_TIME_ELAPSED:
             return state.queries.timer;