wip: render primitive

BUGS=[398198557]

README.md

@@ -31,7 +31,7 @@ repositories {
 }
 
 dependencies {
-    implementation 'com.google.android.filament:filament-android:1.59.1'
+    implementation 'com.google.android.filament:filament-android:1.59.2'
 }
 ```
 
@@ -51,7 +51,7 @@ Here are all the libraries available in the group `com.google.android.filament`:
 iOS projects can use CocoaPods to install the latest release:
 
 ```shell
-pod 'Filament', '~> 1.59.1'
+pod 'Filament', '~> 1.59.2'
 ```
 
 ## Documentation

RELEASE_NOTES.md

@@ -7,6 +7,9 @@ A new header is inserted each time a *tag* is created.
 Instead, if you are authoring a PR for the main branch, add your release note to
 [NEW_RELEASE_NOTES.md](./NEW_RELEASE_NOTES.md).
 
+## v1.59.3
+
+
 ## v1.59.2
 
 - Fix build/compile errors when upgrading to MacOS 15.4

android/gradle.properties

@@ -1,5 +1,5 @@
 GROUP=com.google.android.filament
-VERSION_NAME=1.59.1
+VERSION_NAME=1.59.2
 
 POM_DESCRIPTION=Real-time physically based rendering engine for Android.
 

filament/backend/CMakeLists.txt

@@ -507,8 +507,10 @@ if (APPLE OR LINUX)
         test/Arguments.cpp
         test/ImageExpectations.cpp
         test/Lifetimes.cpp
+        test/PlatformRunner.cpp
         test/Shader.cpp
         test/SharedShaders.cpp
+        test/Skip.cpp
         test/test_FeedbackLoops.cpp
         test/test_Blit.cpp
         test/test_MissingRequiredAttributes.cpp

filament/backend/include/backend/BufferObjectStreamDescriptor.h

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

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

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

filament/backend/src/opengl/ShaderCompilerService.cpp

@@ -54,31 +54,27 @@ using namespace utils;
 
 // ------------------------------------------------------------------------------------------------
 
-static void logCompilationError(utils::io::ostream& out,
-        ShaderStage shaderType, const char* name,
+static inline std::string to_string(bool b) noexcept { return b ? "true" : "false"; }
+static inline std::string to_string(int i) noexcept { return std::to_string(i); }
+static inline std::string to_string(float f) noexcept { return "float(" + std::to_string(f) + ")"; }
+
+static void logCompilationError(io::ostream& out, ShaderStage shaderType, const char* name,
         GLuint shaderId, CString const& sourceCode) noexcept;
+static void logProgramLinkError(io::ostream& out, char const* name, GLuint program) noexcept;
 
-static void logProgramLinkError(utils::io::ostream& out,
-        const char* name, GLuint program) noexcept;
-
-static inline std::string to_string(bool b) noexcept {
-    return b ? "true" : "false";
-}
-
-static inline std::string to_string(int i) noexcept {
-    return std::to_string(i);
-}
-
-static inline std::string to_string(float f) noexcept {
-    return "float(" + std::to_string(f) + ")";
-}
+static void process_GOOGLE_cpp_style_line_directive(OpenGLContext& context, char* source,
+        size_t len) noexcept;
+static void process_OVR_multiview2(OpenGLContext& context, int32_t eyeCount, char* source,
+        size_t len) noexcept;
+static std::string_view process_ARB_shading_language_packing(OpenGLContext& context) noexcept;
+static std::array<std::string_view, 3> splitShaderSource(std::string_view source) noexcept;
 
 // ------------------------------------------------------------------------------------------------
 
 struct ShaderCompilerService::OpenGLProgramToken : ProgramToken {
     struct ProgramData {
         GLuint program{};
-        std::array<GLuint, Program::SHADER_TYPE_COUNT> shaders{};
+        shaders_t shaders{};
     };
 
     ~OpenGLProgramToken() override;
@@ -90,10 +86,10 @@ struct ShaderCompilerService::OpenGLProgramToken : ProgramToken {
     ShaderCompilerService& compiler;
     utils::CString const& name;
     utils::FixedCapacityVector<std::pair<utils::CString, uint8_t>> attributes;
-    std::array<utils::CString, Program::SHADER_TYPE_COUNT> shaderSourceCode;
+    shaders_source_t shaderSourceCode;
     void* user = nullptr;
     struct {
-        std::array<GLuint, Program::SHADER_TYPE_COUNT> shaders{};
+        shaders_t shaders{};
         GLuint program = 0;
     } gl; // 12 bytes
 
@@ -140,11 +136,12 @@ struct ShaderCompilerService::OpenGLProgramToken : ProgramToken {
 
 ShaderCompilerService::OpenGLProgramToken::~OpenGLProgramToken() = default;
 
-void ShaderCompilerService::setUserData(const program_token_t& token, void* user) noexcept {
+/* static */ void ShaderCompilerService::setUserData(const program_token_t& token,
+        void* user) noexcept {
     token->user = user;
 }
 
-void* ShaderCompilerService::getUserData(const program_token_t& token) noexcept {
+/* static */ void* ShaderCompilerService::getUserData(const program_token_t& token) noexcept {
     return token->user;
 }
 
@@ -268,101 +265,111 @@ ShaderCompilerService::program_token_t ShaderCompilerService::createProgram(
     token->handle = mCallbackManager.get();
 
     CompilerPriorityQueue const priorityQueue = program.getPriorityQueue();
-    if (mMode == Mode::THREAD_POOL) {
-        // queue a compile job
-        mCompilerThreadPool.queue(priorityQueue, token,
-                [this, &gl, program = std::move(program), token]() mutable {
-                    // compile the shaders
-                    std::array<GLuint, Program::SHADER_TYPE_COUNT> shaders{};
-                    compileShaders(gl,
-                            std::move(program.getShadersSource()),
-                            program.getSpecializationConstants(),
-                            program.isMultiview(),
-                            shaders,
-                            token->shaderSourceCode);
+    switch (mMode) {
+        case Mode::THREAD_POOL: {
+            // queue a compile job
+            mCompilerThreadPool.queue(priorityQueue, token,
+                    [this, &gl, program = std::move(program), token]() mutable {
+                        // compile the shaders
+                        shaders_t shaders{};
+                        compileShaders(gl,
+                                std::move(program.getShadersSource()),
+                                program.getSpecializationConstants(),
+                                program.isMultiview(),
+                                shaders,
+                                token->shaderSourceCode);
 
-                    // link the program
-                    GLuint const glProgram = linkProgram(gl, shaders, token->attributes);
+                        // link the program
+                        GLuint const glProgram = linkProgram(gl, shaders, token->attributes);
 
-                    OpenGLProgramToken::ProgramData programData;
-                    programData.shaders = shaders;
+                        OpenGLProgramToken::ProgramData programData;
+                        programData.shaders = shaders;
 
-                    // We need to query the link status here to guarantee that the
-                    // program is compiled and linked now (we don't want this to be
-                    // deferred to later). We don't care about the result at this point.
-                    GLint status = GL_FALSE;
-                    glGetProgramiv(glProgram, GL_LINK_STATUS, &status);
-                    programData.program = glProgram;
+                        // We need to query the link status here to guarantee that the
+                        // program is compiled and linked now (we don't want this to be
+                        // deferred to later). We don't care about the result at this point.
+                        GLint status = GL_FALSE;
+                        glGetProgramiv(glProgram, GL_LINK_STATUS, &status);
+                        programData.program = glProgram;
 
-                    // we don't need to check for success here, it'll be done on the
-                    // main thread side.
-                    token->set(programData);
+                        // we don't need to check for success here, it'll be done on the
+                        // main thread side.
+                        token->set(programData);
 
-                    mCallbackManager.put(token->handle);
+                        mCallbackManager.put(token->handle);
 
-                    // caching must be the last thing we do
-                    if (token->key && status == GL_TRUE) {
-                        // Attempt to cache. This calls glGetProgramBinary.
-                        mBlobCache.insert(mDriver.mPlatform, token->key, glProgram);
-                    }
-                });
+                        // caching must be the last thing we do
+                        if (token->key && status == GL_TRUE) {
+                            // Attempt to cache. This calls glGetProgramBinary.
+                            mBlobCache.insert(mDriver.mPlatform, token->key, glProgram);
+                        }
+                    });
+            break;
+        }
 
-    } else {
-        // this cannot fail because we check compilation status after linking the program
-        // shaders[] is filled with id of shader stages present.
-        compileShaders(gl,
-                std::move(program.getShadersSource()),
-                program.getSpecializationConstants(),
-                program.isMultiview(),
-                token->gl.shaders,
-                token->shaderSourceCode);
+        case Mode::SYNCHRONOUS:
+        case Mode::ASYNCHRONOUS: {
+            // this cannot fail because we check compilation status after linking the program
+            // shaders[] is filled with id of shader stages present.
+            compileShaders(gl,
+                    std::move(program.getShadersSource()),
+                    program.getSpecializationConstants(),
+                    program.isMultiview(),
+                    token->gl.shaders,
+                    token->shaderSourceCode);
 
-        runAtNextTick(priorityQueue, token, [this, token](Job const&) {
-            assert_invariant(mMode != Mode::THREAD_POOL);
-            if (mMode == Mode::ASYNCHRONOUS) {
-                // don't attempt to link this program if all shaders are not done compiling
-                GLint status;
-                if (token->gl.program) {
-                    glGetProgramiv(token->gl.program, GL_COMPLETION_STATUS, &status);
-                    if (status == GL_FALSE) {
-                        return false;
-                    }
-                } else {
-                    for (auto shader: token->gl.shaders) {
-                        if (shader) {
-                            glGetShaderiv(shader, GL_COMPLETION_STATUS, &status);
-                            if (status == GL_FALSE) {
-                                return false;
+            runAtNextTick(priorityQueue, token, [this, token](Job const&) {
+                assert_invariant(mMode != Mode::THREAD_POOL);
+                if (mMode == Mode::ASYNCHRONOUS) {
+                    // don't attempt to link this program if all shaders are not done compiling
+                    GLint status;
+                    if (token->gl.program) {
+                        glGetProgramiv(token->gl.program, GL_COMPLETION_STATUS, &status);
+                        if (status == GL_FALSE) {
+                            return false;
+                        }
+                    } else {
+                        for (auto shader: token->gl.shaders) {
+                            if (shader) {
+                                glGetShaderiv(shader, GL_COMPLETION_STATUS, &status);
+                                if (status == GL_FALSE) {
+                                    return false;
+                                }
                             }
                         }
                     }
                 }
-            }
 
-            if (!token->gl.program) {
-                // link the program, this also cannot fail because status is checked later.
-                token->gl.program = linkProgram(mDriver.getContext(),
-                        token->gl.shaders, token->attributes);
-                if (mMode == Mode::ASYNCHRONOUS) {
-                    // wait until the link finishes...
-                    return false;
+                if (!token->gl.program) {
+                    // link the program, this also cannot fail because status is checked later.
+                    token->gl.program = linkProgram(mDriver.getContext(),
+                            token->gl.shaders, token->attributes);
+                    if (mMode == Mode::ASYNCHRONOUS) {
+                        // wait until the link finishes...
+                        return false;
+                    }
                 }
-            }
 
-            assert_invariant(token->gl.program);
+                assert_invariant(token->gl.program);
 
-            mCallbackManager.put(token->handle);
+                mCallbackManager.put(token->handle);
 
-            if (token->key) {
-                // TODO: technically we don't have to cache right now. Is it advantageous to
-                //       do this later, maybe depending on CPU usage?
-                // attempt to cache if we don't have a thread pool (otherwise it's done
-                // by the pool).
-                mBlobCache.insert(mDriver.mPlatform, token->key, token->gl.program);
-            }
+                if (token->key) {
+                    // TODO: technically we don't have to cache right now. Is it advantageous to
+                    //       do this later, maybe depending on CPU usage?
+                    // attempt to cache if we don't have a thread pool (otherwise it's done
+                    // by the pool).
+                    mBlobCache.insert(mDriver.mPlatform, token->key, token->gl.program);
+                }
 
-            return true;
-        });
+                return true;
+            });
+            break;
+        }
+
+        case Mode::UNDEFINED: {
+            assert_invariant(false);
+        }
     }
 
     return token;
@@ -377,12 +384,12 @@ GLuint ShaderCompilerService::getProgram(ShaderCompilerService::program_token_t&
     return program;
 }
 
-void ShaderCompilerService::terminate(program_token_t& token) {
+/* static */ void ShaderCompilerService::terminate(program_token_t& token) {
     assert_invariant(token);
 
     token->canceled = true;
 
-    bool const canceled = token->compiler.cancelTickOp(token);
+    bool const isTickOpCanceled = token->compiler.cancelTickOp(token);
 
     if (token->compiler.mMode == Mode::THREAD_POOL) {
         auto job = token->compiler.mCompilerThreadPool.dequeue(token);
@@ -395,7 +402,7 @@ void ShaderCompilerService::terminate(program_token_t& token) {
             // order for future callbacks to be successfully called.
             token->compiler.mCallbackManager.put(token->handle);
         }
-    } else if (canceled) {
+    } else if (isTickOpCanceled) {
         // Since the tick op was canceled, we need to .put the token here.
         token->compiler.mCallbackManager.put(token->handle);
     }
@@ -432,7 +439,8 @@ void ShaderCompilerService::notifyWhenAllProgramsAreReady(
 
 // ------------------------------------------------------------------------------------------------
 
-void ShaderCompilerService::getProgramFromCompilerPool(program_token_t& token) noexcept {
+/* static */ void ShaderCompilerService::getProgramFromCompilerPool(
+        program_token_t& token) noexcept {
     OpenGLProgramToken::ProgramData const& programData{ token->get() };
     if (!token->canceled) {
         token->gl.shaders = programData.shaders;
@@ -443,40 +451,53 @@ void ShaderCompilerService::getProgramFromCompilerPool(program_token_t& token) n
 GLuint ShaderCompilerService::initialize(program_token_t& token) noexcept {
     SYSTRACE_CALL();
     if (!token->gl.program) {
-        if (mMode == Mode::THREAD_POOL) {
-            // we need this program right now, remove it from the queue
-            auto job = mCompilerThreadPool.dequeue(token);
-            if (job) {
-                // if we were able to remove it, we execute the job now, otherwise it means
-                // it's being executed right now.
-                job();
+        switch (mMode) {
+            case Mode::THREAD_POOL: {
+                // we need this program right now, remove it from the queue
+                auto job = mCompilerThreadPool.dequeue(token);
+                if (job) {
+                    // if we were able to remove it, we execute the job now, otherwise it means
+                    // it's being executed right now.
+                    job();
+                }
+
+                if (!token->canceled) {
+                    token->compiler.cancelTickOp(token);
+                }
+
+                // Block until we get the program from the pool. Generally this wouldn't block
+                // because we just compiled the program above, when executing job.
+                ShaderCompilerService::getProgramFromCompilerPool(token);
+                break;
             }
 
-            if (!token->canceled) {
+            case Mode::ASYNCHRONOUS: {
+                // we force the program link -- which might stall, either here or below in
+                // checkProgramStatus(), but we don't have a choice, we need to use the program now.
                 token->compiler.cancelTickOp(token);
+
+                token->gl.program =
+                        linkProgram(mDriver.getContext(), token->gl.shaders, token->attributes);
+
+                assert_invariant(token->gl.program);
+
+                mCallbackManager.put(token->handle);
+
+                if (token->key) {
+                    mBlobCache.insert(mDriver.mPlatform, token->key, token->gl.program);
+                }
+                break;
             }
 
-            // Block until we get the program from the pool. Generally this wouldn't block
-            // because we just compiled the program above, when executing job.
-            ShaderCompilerService::getProgramFromCompilerPool(token);
-        } else if (mMode == Mode::ASYNCHRONOUS) {
-            // we force the program link -- which might stall, either here or below in
-            // checkProgramStatus(), but we don't have a choice, we need to use the program now.
-            token->compiler.cancelTickOp(token);
-
-            token->gl.program = linkProgram(mDriver.getContext(),
-                    token->gl.shaders, token->attributes);
-
-            assert_invariant(token->gl.program);
-
-            mCallbackManager.put(token->handle);
-
-            if (token->key) {
-                mBlobCache.insert(mDriver.mPlatform, token->key, token->gl.program);
+            case Mode::SYNCHRONOUS: {
+                // if we don't have a program yet, block until we get it.
+                tick();
+                break;
+            }
+
+            case Mode::UNDEFINED: {
+                assert_invariant(false);
             }
-        } else {
-            // if we don't have a program yet, block until we get it.
-            tick();
         }
     }
 
@@ -519,12 +540,12 @@ GLuint ShaderCompilerService::initialize(program_token_t& token) noexcept {
  * checked until after the program is linked.
  * This always returns the GL shader IDs or zero a shader stage is not present.
  */
-void ShaderCompilerService::compileShaders(OpenGLContext& context,
+/* static */ void ShaderCompilerService::compileShaders(OpenGLContext& context,
         Program::ShaderSource shadersSource,
         utils::FixedCapacityVector<Program::SpecializationConstant> const& specializationConstants,
         bool multiview,
-        std::array<GLuint, Program::SHADER_TYPE_COUNT>& outShaders,
-        UTILS_UNUSED_IN_RELEASE std::array<CString, Program::SHADER_TYPE_COUNT>& outShaderSourceCode) noexcept {
+        shaders_t& outShaders,
+        UTILS_UNUSED_IN_RELEASE shaders_source_t& outShaderSourceCode) noexcept {
 
     SYSTRACE_CALL();
 
@@ -635,209 +656,13 @@ void ShaderCompilerService::compileShaders(OpenGLContext& context,
     }
 }
 
-// If usages of the Google-style line directive are present, remove them, as some
-// drivers don't allow the quotation marks. This source modification happens in-place.
-void ShaderCompilerService::process_GOOGLE_cpp_style_line_directive(OpenGLContext& context,
-        char* source, size_t len) noexcept {
-    if (!context.ext.GOOGLE_cpp_style_line_directive) {
-        if (UTILS_UNLIKELY(requestsGoogleLineDirectivesExtension({ source, len }))) {
-            removeGoogleLineDirectives(source, len); // length is unaffected
-        }
-    }
-}
-
-// Look up the `source` to replace the number of eyes for multiview with the given number. This is
-// necessary for OpenGL because OpenGL relies on the number specified in shader files to determine
-// the number of views, which is assumed as a single digit, for multiview.
-// This source modification happens in-place.
-void ShaderCompilerService::process_OVR_multiview2(OpenGLContext& context,
-        int32_t eyeCount, char* source, size_t len) noexcept {
-    // We don't use regular expression in favor of performance.
-    if (context.ext.OVR_multiview2) {
-        const std::string_view shader{ source, len };
-        const std::string_view layout = "layout";
-        const std::string_view num_views = "num_views";
-        size_t found = 0;
-        while (true) {
-            found = shader.find(layout, found);
-            if (found == std::string_view::npos) {
-                break;
-            }
-            found = shader.find_first_not_of(' ', found + layout.size());
-            if (found == std::string_view::npos || shader[found] != '(') {
-                continue;
-            }
-            found = shader.find_first_not_of(' ', found + 1);
-            if (found == std::string_view::npos) {
-                continue;
-            }
-            if (shader.compare(found, num_views.size(), num_views) != 0) {
-                continue;
-            }
-            found = shader.find_first_not_of(' ', found + num_views.size());
-            if (found == std::string_view::npos || shader[found] != '=') {
-                continue;
-            }
-            found = shader.find_first_not_of(' ', found + 1);
-            if (found == std::string_view::npos) {
-                continue;
-            }
-            // We assume the value should be one-digit number.
-            assert_invariant(eyeCount < 10);
-            assert_invariant(!::isdigit(source[found + 1]));
-            source[found] = '0' + eyeCount;
-            break;
-        }
-    }
-}
-
-// Tragically, OpenGL 4.1 doesn't support unpackHalf2x16 (appeared in 4.2) and
-// macOS doesn't support GL_ARB_shading_language_packing
-// Also GLES3.0 didn't have the full set of packing/unpacking functions
-std::string_view ShaderCompilerService::process_ARB_shading_language_packing(OpenGLContext& context) noexcept {
-    using namespace std::literals;
-#ifdef BACKEND_OPENGL_VERSION_GL
-    if (!context.isAtLeastGL<4, 2>() && !context.ext.ARB_shading_language_packing) {
-        return R"(
-
-// these don't handle denormals, NaNs or inf
-float u16tofp32(highp uint v) {
-    v <<= 16u;
-    highp uint s = v & 0x80000000u;
-    highp uint n = v & 0x7FFFFFFFu;
-    highp uint nz = (n == 0u) ? 0u : 0xFFFFFFFFu;
-    return uintBitsToFloat(s | ((((n >> 3u) + (0x70u << 23u))) & nz));
-}
-vec2 unpackHalf2x16(highp uint v) {
-    return vec2(u16tofp32(v&0xFFFFu), u16tofp32(v>>16u));
-}
-uint fp32tou16(float val) {
-    uint f32 = floatBitsToUint(val);
-    uint f16 = 0u;
-    uint sign = (f32 >> 16u) & 0x8000u;
-    int exponent = int((f32 >> 23u) & 0xFFu) - 127;
-    uint mantissa = f32 & 0x007FFFFFu;
-    if (exponent > 15) {
-        f16 = sign | (0x1Fu << 10u);
-    } else if (exponent > -15) {
-        exponent += 15;
-        mantissa >>= 13;
-        f16 = sign | uint(exponent << 10) | mantissa;
-    } else {
-        f16 = sign;
-    }
-    return f16;
-}
-highp uint packHalf2x16(vec2 v) {
-    highp uint x = fp32tou16(v.x);
-    highp uint y = fp32tou16(v.y);
-    return (y << 16u) | x;
-}
-highp uint packUnorm4x8(mediump vec4 v) {
-    v = round(clamp(v, 0.0, 1.0) * 255.0);
-    highp uint a = uint(v.x);
-    highp uint b = uint(v.y) <<  8;
-    highp uint c = uint(v.z) << 16;
-    highp uint d = uint(v.w) << 24;
-    return (a|b|c|d);
-}
-highp uint packSnorm4x8(mediump vec4 v) {
-    v = round(clamp(v, -1.0, 1.0) * 127.0);
-    highp uint a = uint((int(v.x) & 0xff));
-    highp uint b = uint((int(v.y) & 0xff)) <<  8;
-    highp uint c = uint((int(v.z) & 0xff)) << 16;
-    highp uint d = uint((int(v.w) & 0xff)) << 24;
-    return (a|b|c|d);
-}
-mediump vec4 unpackUnorm4x8(highp uint v) {
-    return vec4(float((v & 0x000000ffu)      ),
-                float((v & 0x0000ff00u) >>  8),
-                float((v & 0x00ff0000u) >> 16),
-                float((v & 0xff000000u) >> 24)) / 255.0;
-}
-mediump vec4 unpackSnorm4x8(highp uint v) {
-    int a = int(((v       ) & 0xffu) << 24u) >> 24 ;
-    int b = int(((v >>  8u) & 0xffu) << 24u) >> 24 ;
-    int c = int(((v >> 16u) & 0xffu) << 24u) >> 24 ;
-    int d = int(((v >> 24u) & 0xffu) << 24u) >> 24 ;
-    return clamp(vec4(float(a), float(b), float(c), float(d)) / 127.0, -1.0, 1.0);
-}
-)"sv;
-    }
-#endif // BACKEND_OPENGL_VERSION_GL
-
-#ifdef BACKEND_OPENGL_VERSION_GLES
-    if (!context.isES2() && !context.isAtLeastGLES<3, 1>()) {
-        return R"(
-
-highp uint packUnorm4x8(mediump vec4 v) {
-    v = round(clamp(v, 0.0, 1.0) * 255.0);
-    highp uint a = uint(v.x);
-    highp uint b = uint(v.y) <<  8;
-    highp uint c = uint(v.z) << 16;
-    highp uint d = uint(v.w) << 24;
-    return (a|b|c|d);
-}
-highp uint packSnorm4x8(mediump vec4 v) {
-    v = round(clamp(v, -1.0, 1.0) * 127.0);
-    highp uint a = uint((int(v.x) & 0xff));
-    highp uint b = uint((int(v.y) & 0xff)) <<  8;
-    highp uint c = uint((int(v.z) & 0xff)) << 16;
-    highp uint d = uint((int(v.w) & 0xff)) << 24;
-    return (a|b|c|d);
-}
-mediump vec4 unpackUnorm4x8(highp uint v) {
-    return vec4(float((v & 0x000000ffu)      ),
-                float((v & 0x0000ff00u) >>  8),
-                float((v & 0x00ff0000u) >> 16),
-                float((v & 0xff000000u) >> 24)) / 255.0;
-}
-mediump vec4 unpackSnorm4x8(highp uint v) {
-    int a = int(((v       ) & 0xffu) << 24u) >> 24 ;
-    int b = int(((v >>  8u) & 0xffu) << 24u) >> 24 ;
-    int c = int(((v >> 16u) & 0xffu) << 24u) >> 24 ;
-    int d = int(((v >> 24u) & 0xffu) << 24u) >> 24 ;
-    return clamp(vec4(float(a), float(b), float(c), float(d)) / 127.0, -1.0, 1.0);
-}
-)"sv;
-    }
-#endif // BACKEND_OPENGL_VERSION_GLES
-    return ""sv;
-}
-
-// split shader source code in three:
-// - the version line
-// - extensions
-// - everything else
-std::array<std::string_view, 3> ShaderCompilerService::splitShaderSource(std::string_view source) noexcept {
-    auto version_start = source.find("#version");
-    assert_invariant(version_start != std::string_view::npos);
-
-    auto version_eol = source.find('\n', version_start) + 1;
-    assert_invariant(version_eol != std::string_view::npos);
-
-    auto prolog_start = version_eol;
-    auto prolog_eol = source.rfind("\n#extension"); // last #extension line
-    if (prolog_eol == std::string_view::npos) {
-        prolog_eol = prolog_start;
-    } else {
-        prolog_eol = source.find('\n', prolog_eol + 1) + 1;
-    }
-    auto body_start = prolog_eol;
-
-    std::string_view const version = source.substr(version_start, version_eol - version_start);
-    std::string_view const prolog = source.substr(prolog_start, prolog_eol - prolog_start);
-    std::string_view const body = source.substr(body_start, source.length() - body_start);
-    return { version, prolog, body };
-}
-
 /*
  * Create a program from the given shader IDs and links it. This cannot fail because errors
  * are checked later. This always returns a valid GL program ID (which doesn't mean the
  * program itself is valid).
  */
-GLuint ShaderCompilerService::linkProgram(OpenGLContext& context,
-        std::array<GLuint, Program::SHADER_TYPE_COUNT> shaders,
+/* static */ GLuint ShaderCompilerService::linkProgram(OpenGLContext& context,
+        shaders_t const& shaders,
         utils::FixedCapacityVector<std::pair<utils::CString, uint8_t>> const& attributes) noexcept {
 
     SYSTRACE_CALL();
@@ -913,7 +738,7 @@ void ShaderCompilerService::executeTickOps() noexcept {
  * Checks a program link status and logs errors and frees resources on failure.
  * Returns true on success.
  */
-bool ShaderCompilerService::checkProgramStatus(program_token_t const& token) noexcept {
+/* static */ bool ShaderCompilerService::checkProgramStatus(program_token_t const& token) noexcept {
 
     SYSTRACE_CALL();
 
@@ -948,20 +773,24 @@ bool ShaderCompilerService::checkProgramStatus(program_token_t const& token) noe
     return false;
 }
 
+// ------------------------------------------------------------------------------------------------
+
 UTILS_NOINLINE
-void logCompilationError(io::ostream& out, ShaderStage shaderType,
-        const char* name, GLuint shaderId,
-        UTILS_UNUSED_IN_RELEASE CString const& sourceCode) noexcept {
+/* static */ void logCompilationError(io::ostream& out, ShaderStage shaderType, const char* name,
+        GLuint shaderId, UTILS_UNUSED_IN_RELEASE CString const& sourceCode) noexcept {
 
     auto to_string = [](ShaderStage type) -> const char* {
         switch (type) {
-            case ShaderStage::VERTEX:   return "vertex";
-            case ShaderStage::FRAGMENT: return "fragment";
-            case ShaderStage::COMPUTE:  return "compute";
+            case ShaderStage::VERTEX:
+                return "vertex";
+            case ShaderStage::FRAGMENT:
+                return "fragment";
+            case ShaderStage::COMPUTE:
+                return "compute";
         }
     };
 
-    { // scope for the temporary string storage
+    {// scope for the temporary string storage
         GLint length = 0;
         glGetShaderiv(shaderId, GL_INFO_LOG_LENGTH, &length);
 
@@ -969,8 +798,7 @@ void logCompilationError(io::ostream& out, ShaderStage shaderType,
         glGetShaderInfoLog(shaderId, length, nullptr, infoLog.data());
 
         out << "Compilation error in " << to_string(shaderType) << " shader \"" << name << "\":\n"
-            << "\"" << infoLog.c_str() << "\""
-            << io::endl;
+            << "\"" << infoLog.c_str() << "\"" << io::endl;
     }
 
 #ifndef NDEBUG
@@ -996,7 +824,7 @@ void logCompilationError(io::ostream& out, ShaderStage shaderType,
 }
 
 UTILS_NOINLINE
-void logProgramLinkError(io::ostream& out, char const* name, GLuint program) noexcept {
+/* static */ void logProgramLinkError(io::ostream& out, char const* name, GLuint program) noexcept {
     GLint length = 0;
     glGetProgramiv(program, GL_INFO_LOG_LENGTH, &length);
 
@@ -1004,9 +832,204 @@ void logProgramLinkError(io::ostream& out, char const* name, GLuint program) noe
     glGetProgramInfoLog(program, length, nullptr, infoLog.data());
 
     out << "Link error in \"" << name << "\":\n"
-        << "\"" << infoLog.c_str() << "\""
-        << io::endl;
+        << "\"" << infoLog.c_str() << "\"" << io::endl;
 }
 
+// If usages of the Google-style line directive are present, remove them, as some
+// drivers don't allow the quotation marks. This source modification happens in-place.
+/* static */ void process_GOOGLE_cpp_style_line_directive(OpenGLContext& context, char* source,
+        size_t len) noexcept {
+    if (!context.ext.GOOGLE_cpp_style_line_directive) {
+        if (UTILS_UNLIKELY(requestsGoogleLineDirectivesExtension({ source, len }))) {
+            removeGoogleLineDirectives(source, len);// length is unaffected
+        }
+    }
+}
+
+// Look up the `source` to replace the number of eyes for multiview with the given number. This is
+// necessary for OpenGL because OpenGL relies on the number specified in shader files to determine
+// the number of views, which is assumed as a single digit, for multiview.
+// This source modification happens in-place.
+/* static */ void process_OVR_multiview2(OpenGLContext& context, int32_t eyeCount, char* source,
+        size_t len) noexcept {
+    // We don't use regular expression in favor of performance.
+    if (context.ext.OVR_multiview2) {
+        const std::string_view shader{ source, len };
+        const std::string_view layout = "layout";
+        const std::string_view num_views = "num_views";
+        size_t found = 0;
+        while (true) {
+            found = shader.find(layout, found);
+            if (found == std::string_view::npos) {
+                break;
+            }
+            found = shader.find_first_not_of(' ', found + layout.size());
+            if (found == std::string_view::npos || shader[found] != '(') {
+                continue;
+            }
+            found = shader.find_first_not_of(' ', found + 1);
+            if (found == std::string_view::npos) {
+                continue;
+            }
+            if (shader.compare(found, num_views.size(), num_views) != 0) {
+                continue;
+            }
+            found = shader.find_first_not_of(' ', found + num_views.size());
+            if (found == std::string_view::npos || shader[found] != '=') {
+                continue;
+            }
+            found = shader.find_first_not_of(' ', found + 1);
+            if (found == std::string_view::npos) {
+                continue;
+            }
+            // We assume the value should be one-digit number.
+            assert_invariant(eyeCount < 10);
+            assert_invariant(!::isdigit(source[found + 1]));
+            source[found] = '0' + eyeCount;
+            break;
+        }
+    }
+}
+
+// Tragically, OpenGL 4.1 doesn't support unpackHalf2x16 (appeared in 4.2) and
+// macOS doesn't support GL_ARB_shading_language_packing
+// Also GLES3.0 didn't have the full set of packing/unpacking functions
+/* static */ std::string_view process_ARB_shading_language_packing(
+        OpenGLContext& context) noexcept {
+    using namespace std::literals;
+#ifdef BACKEND_OPENGL_VERSION_GL
+    if (!context.isAtLeastGL<4, 2>() && !context.ext.ARB_shading_language_packing) {
+        return R"(
+
+// these don't handle denormals, NaNs or inf
+float u16tofp32(highp uint v) {
+    v <<= 16u;
+    highp uint s = v & 0x80000000u;
+    highp uint n = v & 0x7FFFFFFFu;
+    highp uint nz = (n == 0u) ? 0u : 0xFFFFFFFFu;
+    return uintBitsToFloat(s | ((((n >> 3u) + (0x70u << 23u))) & nz));
+}
+vec2 unpackHalf2x16(highp uint v) {
+    return vec2(u16tofp32(v&0xFFFFu), u16tofp32(v>>16u));
+}
+uint fp32tou16(float val) {
+    uint f32 = floatBitsToUint(val);
+    uint f16 = 0u;
+    uint sign = (f32 >> 16u) & 0x8000u;
+    int exponent = int((f32 >> 23u) & 0xFFu) - 127;
+    uint mantissa = f32 & 0x007FFFFFu;
+    if (exponent > 15) {
+        f16 = sign | (0x1Fu << 10u);
+    } else if (exponent > -15) {
+        exponent += 15;
+        mantissa >>= 13;
+        f16 = sign | uint(exponent << 10) | mantissa;
+    } else {
+        f16 = sign;
+    }
+    return f16;
+}
+highp uint packHalf2x16(vec2 v) {
+    highp uint x = fp32tou16(v.x);
+    highp uint y = fp32tou16(v.y);
+    return (y << 16u) | x;
+}
+highp uint packUnorm4x8(mediump vec4 v) {
+    v = round(clamp(v, 0.0, 1.0) * 255.0);
+    highp uint a = uint(v.x);
+    highp uint b = uint(v.y) <<  8;
+    highp uint c = uint(v.z) << 16;
+    highp uint d = uint(v.w) << 24;
+    return (a|b|c|d);
+}
+highp uint packSnorm4x8(mediump vec4 v) {
+    v = round(clamp(v, -1.0, 1.0) * 127.0);
+    highp uint a = uint((int(v.x) & 0xff));
+    highp uint b = uint((int(v.y) & 0xff)) <<  8;
+    highp uint c = uint((int(v.z) & 0xff)) << 16;
+    highp uint d = uint((int(v.w) & 0xff)) << 24;
+    return (a|b|c|d);
+}
+mediump vec4 unpackUnorm4x8(highp uint v) {
+    return vec4(float((v & 0x000000ffu)      ),
+                float((v & 0x0000ff00u) >>  8),
+                float((v & 0x00ff0000u) >> 16),
+                float((v & 0xff000000u) >> 24)) / 255.0;
+}
+mediump vec4 unpackSnorm4x8(highp uint v) {
+    int a = int(((v       ) & 0xffu) << 24u) >> 24 ;
+    int b = int(((v >>  8u) & 0xffu) << 24u) >> 24 ;
+    int c = int(((v >> 16u) & 0xffu) << 24u) >> 24 ;
+    int d = int(((v >> 24u) & 0xffu) << 24u) >> 24 ;
+    return clamp(vec4(float(a), float(b), float(c), float(d)) / 127.0, -1.0, 1.0);
+}
+)"sv;
+    }
+#endif// BACKEND_OPENGL_VERSION_GL
+
+#ifdef BACKEND_OPENGL_VERSION_GLES
+    if (!context.isES2() && !context.isAtLeastGLES<3, 1>()) {
+        return R"(
+
+highp uint packUnorm4x8(mediump vec4 v) {
+    v = round(clamp(v, 0.0, 1.0) * 255.0);
+    highp uint a = uint(v.x);
+    highp uint b = uint(v.y) <<  8;
+    highp uint c = uint(v.z) << 16;
+    highp uint d = uint(v.w) << 24;
+    return (a|b|c|d);
+}
+highp uint packSnorm4x8(mediump vec4 v) {
+    v = round(clamp(v, -1.0, 1.0) * 127.0);
+    highp uint a = uint((int(v.x) & 0xff));
+    highp uint b = uint((int(v.y) & 0xff)) <<  8;
+    highp uint c = uint((int(v.z) & 0xff)) << 16;
+    highp uint d = uint((int(v.w) & 0xff)) << 24;
+    return (a|b|c|d);
+}
+mediump vec4 unpackUnorm4x8(highp uint v) {
+    return vec4(float((v & 0x000000ffu)      ),
+                float((v & 0x0000ff00u) >>  8),
+                float((v & 0x00ff0000u) >> 16),
+                float((v & 0xff000000u) >> 24)) / 255.0;
+}
+mediump vec4 unpackSnorm4x8(highp uint v) {
+    int a = int(((v       ) & 0xffu) << 24u) >> 24 ;
+    int b = int(((v >>  8u) & 0xffu) << 24u) >> 24 ;
+    int c = int(((v >> 16u) & 0xffu) << 24u) >> 24 ;
+    int d = int(((v >> 24u) & 0xffu) << 24u) >> 24 ;
+    return clamp(vec4(float(a), float(b), float(c), float(d)) / 127.0, -1.0, 1.0);
+}
+)"sv;
+    }
+#endif// BACKEND_OPENGL_VERSION_GLES
+    return ""sv;
+}
+
+// split shader source code in three:
+// - the version line
+// - extensions
+// - everything else
+/* static */ std::array<std::string_view, 3> splitShaderSource(std::string_view source) noexcept {
+    auto version_start = source.find("#version");
+    assert_invariant(version_start != std::string_view::npos);
+
+    auto version_eol = source.find('\n', version_start) + 1;
+    assert_invariant(version_eol != std::string_view::npos);
+
+    auto prolog_start = version_eol;
+    auto prolog_eol = source.rfind("\n#extension");// last #extension line
+    if (prolog_eol == std::string_view::npos) {
+        prolog_eol = prolog_start;
+    } else {
+        prolog_eol = source.find('\n', prolog_eol + 1) + 1;
+    }
+    auto body_start = prolog_eol;
+
+    std::string_view const version = source.substr(version_start, version_eol - version_start);
+    std::string_view const prolog = source.substr(prolog_start, prolog_eol - prolog_start);
+    std::string_view const body = source.substr(body_start, source.length() - body_start);
+    return { version, prolog, body };
+}
 
 } // namespace filament::backend

filament/backend/src/opengl/ShaderCompilerService.h

@@ -57,6 +57,8 @@ class ShaderCompilerService {
 
 public:
     using program_token_t = std::shared_ptr<OpenGLProgramToken>;
+    using shaders_t = std::array<GLuint, Program::SHADER_TYPE_COUNT>;
+    using shaders_source_t = std::array<utils::CString, Program::SHADER_TYPE_COUNT>;
 
     explicit ShaderCompilerService(OpenGLDriver& driver);
 
@@ -134,22 +136,9 @@ private:
             OpenGLContext& context,
             Program::ShaderSource shadersSource,
             utils::FixedCapacityVector<Program::SpecializationConstant> const& specializationConstants,
-            bool multiview,
-            std::array<GLuint, Program::SHADER_TYPE_COUNT>& outShaders,
-            std::array<utils::CString, Program::SHADER_TYPE_COUNT>& outShaderSourceCode) noexcept;
+            bool multiview, shaders_t& outShaders, shaders_source_t& outShaderSourceCode) noexcept;
 
-    static void process_GOOGLE_cpp_style_line_directive(OpenGLContext& context,
-            char* source, size_t len) noexcept;
-
-    static void process_OVR_multiview2(OpenGLContext& context, int32_t eyeCount,
-            char* source, size_t len) noexcept;
-
-    static std::string_view process_ARB_shading_language_packing(OpenGLContext& context) noexcept;
-
-    static std::array<std::string_view, 3> splitShaderSource(std::string_view source) noexcept;
-
-    static GLuint linkProgram(OpenGLContext& context,
-            std::array<GLuint, Program::SHADER_TYPE_COUNT> shaders,
+    static GLuint linkProgram(OpenGLContext& context, shaders_t const& shaders,
             utils::FixedCapacityVector<std::pair<utils::CString, uint8_t>> const& attributes) noexcept;
 
     static bool checkProgramStatus(program_token_t const& token) noexcept;

filament/backend/src/ostream.cpp

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

filament/backend/src/vulkan/VulkanDriver.cpp

@@ -327,7 +327,7 @@ void VulkanDriver::terminate() {
 
     mStagePool.terminate();
     mPipelineCache.terminate();
-    mFramebufferCache.reset();
+    mFramebufferCache.terminate();
     mSamplerCache.terminate();
     mDescriptorSetLayoutCache.terminate();
     mDescriptorSetCache.terminate();
@@ -1523,7 +1523,7 @@ void VulkanDriver::makeCurrent(Handle<HwSwapChain> drawSch, Handle<HwSwapChain>
     swapChain->acquire(resized);
 
     if (resized) {
-        mFramebufferCache.reset();
+        mFramebufferCache.resetFramebuffers();
     }
 
     if (UTILS_LIKELY(mDefaultRenderTarget)) {

filament/backend/src/vulkan/VulkanFboCache.cpp

@@ -340,15 +340,21 @@ VkRenderPass VulkanFboCache::getRenderPass(RenderPassKey const& config) noexcept
     return renderPass;
 }
 
-void VulkanFboCache::reset() noexcept {
-    for (auto pair : mFramebufferCache) {
+void VulkanFboCache::resetFramebuffers() noexcept {
+    for (const auto& pair: mFramebufferCache) {
         mRenderPassRefCount[pair.first.renderPass]--;
         vkDestroyFramebuffer(mDevice, pair.second.handle, VKALLOC);
     }
     mFramebufferCache.clear();
-    for (auto pair : mRenderPassCache) {
+}
+
+void VulkanFboCache::terminate() noexcept {
+    resetFramebuffers();
+
+    for (const auto& pair: mRenderPassCache) {
         vkDestroyRenderPass(mDevice, pair.second.handle, VKALLOC);
     }
+    mRenderPassRefCount.clear();
     mRenderPassCache.clear();
 }
 

filament/backend/src/vulkan/VulkanFboCache.h

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

filament/backend/src/vulkan/platform/VulkanPlatformApple.mm

@@ -24,28 +24,12 @@
 #include <bluevk/BlueVK.h>
 
 // Platform specific includes and defines
-#if defined(__APPLE__)
-    #include <Cocoa/Cocoa.h>
-    #import <Metal/Metal.h>
-    #import <QuartzCore/CAMetalLayer.h>
+#include <Cocoa/Cocoa.h>
+#import <Metal/Metal.h>
+#import <QuartzCore/CAMetalLayer.h>
 
-    #ifndef VK_MVK_macos_surface
-         #error VK_MVK_macos_surface is not defined
-    #endif
-#elif defined(FILAMENT_IOS)
-    // Metal is not available when building for the iOS simulator on Desktop.
-    #define METAL_AVAILABLE __has_include(<QuartzCore/CAMetalLayer.h>)
-    #if METAL_AVAILABLE
-        #import <Metal/Metal.h>
-        #import <QuartzCore/CAMetalLayer.h>
-    #endif
-
-    #ifndef VK_MVK_ios_surface
-        #error VK_MVK_ios_surface is not defined
-    #endif
-    #define METALVIEW_TAG 255
-#else
-    #error Not a supported Apple + Vulkan platform
+#ifndef VK_MVK_macos_surface
+    #error VK_MVK_macos_surface is not defined
 #endif
 
 using namespace bluevk;
@@ -54,11 +38,7 @@ namespace filament::backend {
 
 VulkanPlatform::ExtensionSet VulkanPlatform::getSwapchainInstanceExtensionsImpl() {
     ExtensionSet const ret = {
-    #if defined(__APPLE__)
         VK_MVK_MACOS_SURFACE_EXTENSION_NAME,  // TODO: replace with VK_EXT_metal_surface
-    #elif defined(FILAMENT_IOS) && defined(METAL_AVAILABLE)
-        VK_MVK_IOS_SURFACE_EXTENSION_NAME,
-    #endif
     };
     return ret;
 }
@@ -90,36 +70,20 @@ VkImageView VulkanPlatform::createExternalImageViewImpl(VkDevice device,
 VulkanPlatform::SurfaceBundle VulkanPlatform::createVkSurfaceKHRImpl(void* nativeWindow,
         VkInstance instance, uint64_t flags) noexcept {
     VkSurfaceKHR surface;
-    #if defined(__APPLE__)
-        NSView* nsview = (__bridge NSView*) nativeWindow;
-        FILAMENT_CHECK_POSTCONDITION(nsview) << "Unable to obtain Metal-backed NSView.";
+    NSView* nsview = (__bridge NSView*) nativeWindow;
+    FILAMENT_CHECK_POSTCONDITION(nsview) << "Unable to obtain Metal-backed NSView.";
 
-        // Create the VkSurface.
-        FILAMENT_CHECK_POSTCONDITION(vkCreateMacOSSurfaceMVK)
-                << "Unable to load vkCreateMacOSSurfaceMVK.";
-        VkMacOSSurfaceCreateInfoMVK createInfo = {};
-        createInfo.sType = VK_STRUCTURE_TYPE_MACOS_SURFACE_CREATE_INFO_MVK;
-        createInfo.pView = (__bridge void*) nsview;
-        VkResult result = vkCreateMacOSSurfaceMVK((VkInstance) instance, &createInfo, VKALLOC,
-                (VkSurfaceKHR*) &surface);
-        FILAMENT_CHECK_POSTCONDITION(result == VK_SUCCESS)
-                << "vkCreateMacOSSurfaceMVK. error=" << static_cast<int32_t>(result);
-#elif defined(FILAMENT_IOS) && defined(METAL_AVAILABLE)
-    CAMetalLayer* metalLayer = (CAMetalLayer*) nativeWindow;
     // Create the VkSurface.
-    FILAMENT_CHECK_POSTCONDITION(vkCreateIOSSurfaceMVK)
-            << "Unable to load vkCreateIOSSurfaceMVK function.";
-    VkIOSSurfaceCreateInfoMVK createInfo = {};
-    createInfo.sType = VK_STRUCTURE_TYPE_IOS_SURFACE_CREATE_INFO_MVK;
-    createInfo.pNext = NULL;
-    createInfo.flags = 0;
-    createInfo.pView = metalLayer;
-    VkResult result = vkCreateIOSSurfaceMVK((VkInstance) instance, &createInfo, VKALLOC,
+    FILAMENT_CHECK_POSTCONDITION(vkCreateMacOSSurfaceMVK)
+            << "Unable to load vkCreateMacOSSurfaceMVK.";
+    VkMacOSSurfaceCreateInfoMVK createInfo = {};
+    createInfo.sType = VK_STRUCTURE_TYPE_MACOS_SURFACE_CREATE_INFO_MVK;
+    createInfo.pView = (__bridge void*) nsview;
+    VkResult result = vkCreateMacOSSurfaceMVK((VkInstance) instance, &createInfo, VKALLOC,
             (VkSurfaceKHR*) &surface);
     FILAMENT_CHECK_POSTCONDITION(result == VK_SUCCESS)
-            << "vkCreateIOSSurfaceMVK failed. error=" << static_cast<int32_t>(result);
-#endif
-        return std::make_tuple(surface, VkExtent2D{});
+            << "vkCreateMacOSSurfaceMVK. error=" << static_cast<int32_t>(result);
+    return std::make_tuple(surface, VkExtent2D{});
 }
 
 } // namespace filament::backend

filament/backend/src/webgpu/WebGPUDriver.cpp

@@ -16,6 +16,7 @@
 
 #include "webgpu/WebGPUDriver.h"
 
+#include "WebGPUSwapChain.h"
 #include "webgpu/WebGPUConstants.h"
 #include <backend/platforms/WebGPUPlatform.h>
 
@@ -227,6 +228,14 @@ WebGPUDriver::WebGPUDriver(WebGPUPlatform& platform, const Platform::DriverConfi
               driverConfig.disableHeapHandleTags) {
 #if FWGPU_ENABLED(FWGPU_PRINT_SYSTEM)
     printInstanceDetails(mPlatform.getInstance());
+#endif
+    mAdapter = mPlatform.requestAdapter(nullptr);
+#if FWGPU_ENABLED(FWGPU_PRINT_SYSTEM)
+    printAdapterDetails(mAdapter);
+#endif
+    mDevice = mPlatform.requestDevice(mAdapter);
+#if FWGPU_ENABLED(FWGPU_PRINT_SYSTEM)
+    printDeviceDetails(mDevice);
 #endif
 }
 
@@ -286,15 +295,27 @@ void WebGPUDriver::finish(int) {
 }
 
 void WebGPUDriver::destroyRenderPrimitive(Handle<HwRenderPrimitive> rph) {
+   if (rph) {
+        destructHandle<WGPURenderPrimitive>(rph);
+    }
 }
 
 void WebGPUDriver::destroyVertexBufferInfo(Handle<HwVertexBufferInfo> vbih) {
+   if (vbih) {
+        destructHandle<WGPUVertexBufferInfo>(vbih);
+    }
 }
 
 void WebGPUDriver::destroyVertexBuffer(Handle<HwVertexBuffer> vbh) {
+    if (vbh) {
+        destructHandle<WGPUVertexBuffer>(vbh);
+    }
 }
 
 void WebGPUDriver::destroyIndexBuffer(Handle<HwIndexBuffer> ibh) {
+    if (ibh) {
+        destructHandle<WGPUIndexBuffer>(ibh);
+    }
 }
 
 void WebGPUDriver::destroyBufferObject(Handle<HwBufferObject> boh) {
@@ -310,13 +331,10 @@ void WebGPUDriver::destroyRenderTarget(Handle<HwRenderTarget> rth) {
 }
 
 void WebGPUDriver::destroySwapChain(Handle<HwSwapChain> sch) {
+    if (sch) {
+        destructHandle<WebGPUSwapChain>(sch);
+    }
     mSwapChain = nullptr;
-    // TODO:  use webgpu handle allocator from
-    //        https://github.com/google/filament/pull/8566
-//    if (sch) {
-//        HwSwapChain* hwSwapChain = handleCast<HwSwapChain*>(sch);
-//        destruct(sch, hwSwapChain);
-//    }
 }
 
 void WebGPUDriver::destroyStream(Handle<HwStream> sh) {
@@ -326,16 +344,16 @@ void WebGPUDriver::destroyTimerQuery(Handle<HwTimerQuery> tqh) {
 }
 
 void WebGPUDriver::destroyDescriptorSetLayout(Handle<HwDescriptorSetLayout> tqh) {
+    if (tqh) {
+        destructHandle<WebGPUDescriptorSetLayout>(tqh);
+    }
 }
 
 void WebGPUDriver::destroyDescriptorSet(Handle<HwDescriptorSet> tqh) {
 }
 
 Handle<HwSwapChain> WebGPUDriver::createSwapChainS() noexcept {
-    // TODO:  use webgpu handle allocator from.
-    //        https://github.com/google/filament/pull/8566
-    // return allocAndConstructHandle<HwSwapChain>();
-    return Handle<HwSwapChain>((Handle<HwSwapChain>::HandleId) mNextFakeHandle++);
+    return allocHandle<WebGPUSwapChain>();
 }
 
 Handle<HwSwapChain> WebGPUDriver::createSwapChainHeadlessS() noexcept {
@@ -387,7 +405,7 @@ Handle<HwDescriptorSet> WebGPUDriver::createDescriptorSetS() noexcept {
 }
 
 Handle<HwRenderPrimitive> WebGPUDriver::createRenderPrimitiveS() noexcept {
-    return Handle<HwRenderPrimitive>((Handle<HwRenderPrimitive>::HandleId) mNextFakeHandle++);
+    return allocHandle<WGPURenderPrimitive>();
 }
 
 Handle<HwVertexBufferInfo> WebGPUDriver::createVertexBufferInfoS() noexcept {
@@ -403,8 +421,7 @@ Handle<HwRenderTarget> WebGPUDriver::createDefaultRenderTargetS() noexcept {
 }
 
 Handle<HwDescriptorSetLayout> WebGPUDriver::createDescriptorSetLayoutS() noexcept {
-    return Handle<HwDescriptorSetLayout>(
-            (Handle<HwDescriptorSetLayout>::HandleId) mNextFakeHandle++);
+    return allocHandle<WebGPUDescriptorSetLayout>();
 }
 
 Handle<HwTexture> WebGPUDriver::createTextureExternalImageS() noexcept {
@@ -420,21 +437,15 @@ Handle<HwTexture> WebGPUDriver::createTextureExternalImagePlaneS() noexcept {
 }
 
 void WebGPUDriver::createSwapChainR(Handle<HwSwapChain> sch, void* nativeWindow, uint64_t flags) {
-    // TODO:  use webgpu handle allocator from.
-    //        https://github.com/google/filament/pull/8566
-    // HwSwapChain* hwSwapChain = handleCast<HwSwapChain*>(sch);
+    mNativeWindow = nativeWindow;
     assert_invariant(!mSwapChain);
     wgpu::Surface surface = mPlatform.createSurface(nativeWindow, flags);
-    mAdapter = mPlatform.requestAdapter(surface);
-#if FWGPU_ENABLED(FWGPU_PRINT_SYSTEM)
-    printAdapterDetails(mAdapter);
-#endif
-    mDevice = mPlatform.requestDevice(mAdapter);
-#if FWGPU_ENABLED(FWGPU_PRINT_SYSTEM)
-    printDeviceDetails(mDevice);
-#endif
+
     mQueue = mDevice.GetQueue();
-    mSwapChain = std::make_unique<WebGPUSwapChain>(std::move(surface), mAdapter, mDevice, flags);
+    wgpu::Extent2D surfaceSize = mPlatform.getSurfaceExtent(mNativeWindow);
+    mSwapChain = constructHandle<WebGPUSwapChain>(sch, std::move(surface), surfaceSize, mAdapter,
+            mDevice, flags);
+    assert_invariant(mSwapChain);
     FWGPU_LOGW << "WebGPU support is still essentially a no-op at this point in development (only "
                   "background components have been instantiated/selected, such as surface/screen, "
                   "graphics device/GPU, etc.), thus nothing is being drawn to the screen."
@@ -447,22 +458,27 @@ void WebGPUDriver::createSwapChainR(Handle<HwSwapChain> sch, void* nativeWindow,
                   "rebuilding Filament with that flag, e.g. ./build.sh -x "
                << FWGPU_PRINT_SYSTEM << " ..." << utils::io::endl;
 #endif
-    // TODO:  use webgpu handle allocator from.
-    //        https://github.com/google/filament/pull/8566
-    // hwSwapChain->swapChain = mSwapChain.get();
 }
 
 void WebGPUDriver::createSwapChainHeadlessR(Handle<HwSwapChain> sch, uint32_t width,
         uint32_t height, uint64_t flags) {}
 
 void WebGPUDriver::createVertexBufferInfoR(Handle<HwVertexBufferInfo> vbih, uint8_t bufferCount,
-        uint8_t attributeCount, AttributeArray attributes) {}
+        uint8_t attributeCount, AttributeArray attributes) {
+    constructHandle<WGPUVertexBufferInfo>(vbih, bufferCount, attributeCount, attributes);
+}
 
 void WebGPUDriver::createVertexBufferR(Handle<HwVertexBuffer> vbh, uint32_t vertexCount,
-        Handle<HwVertexBufferInfo> vbih) {}
+        Handle<HwVertexBufferInfo> vbih) {
+    auto* vertexBufferInfo = handleCast<WGPUVertexBufferInfo>(vbih);
+    constructHandle<WGPUVertexBuffer>(vbh, mDevice, vertexCount,vertexBufferInfo->bufferCount, vbih);
+}
 
 void WebGPUDriver::createIndexBufferR(Handle<HwIndexBuffer> ibh, ElementType elementType,
-        uint32_t indexCount, BufferUsage usage) {}
+        uint32_t indexCount, BufferUsage usage) {
+    auto elementSize = (uint8_t)getElementTypeSize(elementType);
+    constructHandle<WGPUIndexBuffer>(ibh, mDevice, elementSize, indexCount);
+}
 
 void WebGPUDriver::createBufferObjectR(Handle<HwBufferObject> boh, uint32_t byteCount,
         BufferObjectBinding bindingType, BufferUsage usage) {}
@@ -495,7 +511,18 @@ void WebGPUDriver::importTextureR(Handle<HwTexture> th, intptr_t id, SamplerType
         uint32_t depth, TextureUsage usage) {}
 
 void WebGPUDriver::createRenderPrimitiveR(Handle<HwRenderPrimitive> rph, Handle<HwVertexBuffer> vbh,
-        Handle<HwIndexBuffer> ibh, PrimitiveType pt) {}
+        Handle<HwIndexBuffer> ibh, PrimitiveType pt) {
+    assert_invariant(mDevice);
+
+    auto* renderPrimitive = handleCast<WGPURenderPrimitive>(rph);
+    auto* vertexBuffer = handleCast<WGPUVertexBuffer>(vbh);
+    auto* indexBuffer = handleCast<WGPUIndexBuffer>(ibh);
+    // auto* vertexBufferInfo = handleCast<WGPUVertexBufferInfo>(vertexBuffer->vbih);
+    // renderPrimitive->setBuffers(vertexBufferInfo, vertexBuffer, indexBuffer);
+    renderPrimitive->vertexBuffer = vertexBuffer;
+    renderPrimitive->indexBuffer = indexBuffer;
+    renderPrimitive->type = pt;
+}
 
 void WebGPUDriver::createProgramR(Handle<HwProgram> ph, Program&& program) {}
 
@@ -514,7 +541,9 @@ void WebGPUDriver::createFenceR(Handle<HwFence> fh, int) {}
 void WebGPUDriver::createTimerQueryR(Handle<HwTimerQuery> tqh, int) {}
 
 void WebGPUDriver::createDescriptorSetLayoutR(Handle<HwDescriptorSetLayout> dslh,
-        backend::DescriptorSetLayout&& info) {}
+        backend::DescriptorSetLayout&& info) {
+    constructHandle<WebGPUDescriptorSetLayout>(dslh, std::move(info), &mDevice);
+}
 
 void WebGPUDriver::createDescriptorSetR(Handle<HwDescriptorSet> dsh,
         Handle<HwDescriptorSetLayout> dslh) {}
@@ -706,9 +735,6 @@ void WebGPUDriver::beginRenderPass(Handle<HwRenderTarget> rth, const RenderPassP
     mCommandEncoder = mDevice.CreateCommandEncoder(&commandEncoderDescriptor);
     assert_invariant(mCommandEncoder);
 
-    mTextureView = mSwapChain->getNextSurfaceTextureView(params.viewport.width, params.viewport.height);
-    assert_invariant(mTextureView);
-
     // TODO: Remove this code once WebGPU pipeline is implemented
     static float red = 1.0f;
     if (red - 0.01 > 0) {
@@ -716,7 +742,7 @@ void WebGPUDriver::beginRenderPass(Handle<HwRenderTarget> rth, const RenderPassP
     } else {
         red = 1.0f;
     }
-
+    assert_invariant(mTextureView);
     wgpu::RenderPassColorAttachment renderPassColorAttachment = {
         .view = mTextureView,
         // TODO: remove this code once WebGPU Pipeline is implemented with render targets, pipeline and buffers.
@@ -752,6 +778,14 @@ void WebGPUDriver::nextSubpass(int) {
 }
 
 void WebGPUDriver::makeCurrent(Handle<HwSwapChain> drawSch, Handle<HwSwapChain> readSch) {
+    ASSERT_PRECONDITION_NON_FATAL(drawSch == readSch,
+            "WebGPU driver does not support distinct draw/read swap chains.");
+    auto* swapChain = handleCast<WebGPUSwapChain>(drawSch);
+    mSwapChain = swapChain;
+    assert_invariant(mSwapChain);
+    wgpu::Extent2D surfaceSize = mPlatform.getSurfaceExtent(mNativeWindow);
+    mTextureView = mSwapChain->getCurrentSurfaceTextureView(surfaceSize);
+    assert_invariant(mTextureView);
 }
 
 void WebGPUDriver::commit(Handle<HwSwapChain> sch) {
@@ -759,6 +793,7 @@ void WebGPUDriver::commit(Handle<HwSwapChain> sch) {
     mQueue.Submit(1, &mCommandBuffer);
     mCommandBuffer = nullptr;
     mTextureView = nullptr;
+    assert_invariant(mSwapChain);
     mSwapChain->present();
 }
 
@@ -813,6 +848,70 @@ void WebGPUDriver::bindPipeline(PipelineState const& pipelineState) {
 }
 
 void WebGPUDriver::bindRenderPrimitive(Handle<HwRenderPrimitive> rph) {
+    // VulkanCommandBuffer* commands = mCurrentRenderPass.commandBuffer;
+    // VkCommandBuffer cmdbuffer = commands->buffer();
+    // auto prim = resource_ptr<VulkanRenderPrimitive>::cast(&mResourceManager, rph);
+    auto* renderPrimitive = handleCast<WGPURenderPrimitive>(rph);
+    // commands->acquire(prim);
+
+    // This *must* match the VulkanVertexBufferInfo that was bound in bindPipeline(). But we want
+    // to allow to call this before bindPipeline(), so the validation can only happen in draw()
+    auto vbi = handleCast<WGPUVertexBufferInfo>(renderPrimitive->vertexBuffer->vbih);
+    (void) vbi;
+
+    // mRenderPassEncoder.SetVertexBuffer(uint32_t slot, Buffer const& buffer = nullptr, uint64_t offset = 0, uint64_t size = kWholeSize);
+    mRenderPassEncoder.SetIndexBuffer(renderPrimitive->indexBuffer->buffer, renderPrimitive->indexBuffer->indexFormat);
+
+    // uint32_t const bufferCount = vbi->getAttributeCount();
+    // VkDeviceSize const* offsets = vbi->getOffsets();
+    // VkBuffer const* buffers = prim->vertexBuffer->getVkBuffers();
+    //
+    // // Next bind the vertex buffers and index buffer. One potential performance improvement is to
+    // // avoid rebinding these if they are already bound, but since we do not (yet) support subranges
+    // // it would be rare for a client to make consecutive draw calls with the same render primitive.
+    // vkCmdBindVertexBuffers(cmdbuffer, 0, bufferCount, buffers, offsets);
+    // vkCmdBindIndexBuffer(cmdbuffer, prim->indexBuffer->buffer.getGpuBuffer(), 0,
+    //         prim->indexBuffer->indexType);
+
+
+    // METAL
+    // if (UTILS_UNLIKELY(mContext->currentRenderPassAbandoned)) {
+    //     return;
+    // }
+    // FILAMENT_CHECK_PRECONDITION(mContext->currentRenderPassEncoder != nullptr)
+    //         << "bindRenderPrimitive() without a valid command encoder.";
+    //
+    // // Bind the user vertex buffers.
+    // MetalBuffer* vertexBuffers[MAX_VERTEX_BUFFER_COUNT] = {};
+    // size_t vertexBufferOffsets[MAX_VERTEX_BUFFER_COUNT] = {};
+    // size_t maxBufferIndex = 0;
+    //
+    // MetalRenderPrimitive const* const primitive = handle_cast<MetalRenderPrimitive>(rph);
+    // MetalVertexBufferInfo const* const vbi =
+    //         handle_cast<MetalVertexBufferInfo>(primitive->vertexBuffer->vbih);
+    //
+    // mContext->currentRenderPrimitive = rph;
+    //
+    // auto vb = primitive->vertexBuffer;
+    // for (auto m : vbi->bufferMapping) {
+    //     assert_invariant(
+    //             m.bufferArgumentIndex >= USER_VERTEX_BUFFER_BINDING_START &&
+    //             m.bufferArgumentIndex < USER_VERTEX_BUFFER_BINDING_START + MAX_VERTEX_BUFFER_COUNT);
+    //     size_t const vertexBufferIndex = m.bufferArgumentIndex - USER_VERTEX_BUFFER_BINDING_START;
+    //     vertexBuffers[vertexBufferIndex] = vb->buffers[m.sourceBufferIndex];
+    //     maxBufferIndex = std::max(maxBufferIndex, vertexBufferIndex);
+    // }
+    //
+    // const auto bufferCount = maxBufferIndex + 1;
+    // MetalBuffer::bindBuffers(getPendingCommandBuffer(mContext), mContext->currentRenderPassEncoder,
+    //         USER_VERTEX_BUFFER_BINDING_START, MetalBuffer::Stage::VERTEX, vertexBuffers,
+    //         vertexBufferOffsets, bufferCount);
+    //
+    // // Bind the zero buffer, used for missing vertex attributes.
+    // static const char bytes[16] = { 0 };
+    // [mContext->currentRenderPassEncoder setVertexBytes:bytes
+    //                                             length:16
+    //                                            atIndex:ZERO_VERTEX_BUFFER_BINDING];
 }
 
 void WebGPUDriver::draw2(uint32_t indexOffset, uint32_t indexCount, uint32_t instanceCount) {

filament/backend/src/webgpu/WebGPUDriver.h

@@ -18,7 +18,6 @@
 #define TNT_FILAMENT_BACKEND_WEBGPUDRIVER_H
 
 #include "WebGPUHandles.h"
-#include "webgpu/WebGPUSwapChain.h"
 #include <backend/platforms/WebGPUPlatform.h>
 
 #include "DriverBase.h"
@@ -40,6 +39,8 @@
 
 namespace filament::backend {
 
+class WebGPUSwapChain;
+
 /**
  * WebGPU backend (driver) implementation
  */
@@ -61,8 +62,8 @@ private:
     wgpu::Adapter mAdapter = nullptr;
     wgpu::Device mDevice = nullptr;
     wgpu::Queue mQueue = nullptr;
-    // TODO consider moving to handle allocator when ready
-    std::unique_ptr<WebGPUSwapChain> mSwapChain = nullptr;
+    void* mNativeWindow = nullptr;
+    WebGPUSwapChain* mSwapChain = nullptr;
     uint64_t mNextFakeHandle = 1;
     wgpu::CommandEncoder mCommandEncoder = nullptr;
     wgpu::TextureView mTextureView = nullptr;
@@ -102,11 +103,17 @@ private:
     D* constructHandle(Handle<B>& handle, ARGS&& ... args) noexcept {
         return mHandleAllocator.construct<D>(handle, std::forward<ARGS>(args)...);
     }
+
     template<typename D, typename B>
     D* handleCast(Handle<B> handle) noexcept {
         return mHandleAllocator.handle_cast<D*>(handle);
     }
 
+    template<typename D, typename B>
+    void destructHandle(Handle<B>& handle) noexcept {
+        auto* p = mHandleAllocator.handle_cast<D*>(handle);
+        mHandleAllocator.deallocate(handle, p);
+    }
 };
 
 }// namespace filament::backend

filament/backend/src/webgpu/WebGPUHandles.cpp

@@ -16,13 +16,150 @@
 
 #include "WebGPUHandles.h"
 
+#include <utility>
+
+namespace {
+
+wgpu::Buffer createIndexBuffer(wgpu::Device const& device, uint8_t elementSize, uint32_t indexCount) {
+    wgpu::BufferDescriptor descriptor{ .label = "index_buffer",
+        .usage = wgpu::BufferUsage::CopyDst | wgpu::BufferUsage::Index,
+        .size = elementSize * indexCount,
+        .mappedAtCreation = false };
+    return device.CreateBuffer(&descriptor);
+}
+
+wgpu::VertexFormat getVertexFormat(filament::backend::ElementType type, bool normalized, bool integer) {
+    using ElementType = filament::backend::ElementType;
+    // using VertexFormat = wgpu::VertexFormat;
+    if (normalized) {
+        switch (type) {
+            // Single Component Types
+            case ElementType::BYTE: return wgpu::VertexFormat::Snorm8;
+            case ElementType::UBYTE: return wgpu::VertexFormat::Unorm8;
+            case ElementType::SHORT: return wgpu::VertexFormat::Snorm16;
+            case ElementType::USHORT: return wgpu::VertexFormat::Unorm16;
+            // Two Component Types
+            case ElementType::BYTE2: return wgpu::VertexFormat::Snorm8x2;
+            case ElementType::UBYTE2: return wgpu::VertexFormat::Unorm8x2;
+            case ElementType::SHORT2: return wgpu::VertexFormat::Snorm16x2;
+            case ElementType::USHORT2: return wgpu::VertexFormat::Unorm16x2;
+            // Three Component Types
+            // There is no vertex format type for 3 byte data in webgpu. Use
+            // 4 byte signed normalized type and ignore the last byte.
+            // TODO: This is to be verified.
+            case ElementType::BYTE3: return wgpu::VertexFormat::Snorm8x4;      // NOT MINSPEC
+            case ElementType::UBYTE3: return wgpu::VertexFormat::Unorm8x4;     // NOT MINSPEC
+            case ElementType::SHORT3: return wgpu::VertexFormat::Snorm16x4;  // NOT MINSPEC
+            case ElementType::USHORT3: return wgpu::VertexFormat::Unorm16x4; // NOT MINSPEC
+            // Four Component Types
+            case ElementType::BYTE4: return wgpu::VertexFormat::Snorm8x4;
+            case ElementType::UBYTE4: return wgpu::VertexFormat::Unorm8x4;
+            case ElementType::SHORT4: return wgpu::VertexFormat::Snorm16x4;
+            case ElementType::USHORT4: return wgpu::VertexFormat::Unorm8x4;
+            default:
+                FILAMENT_CHECK_POSTCONDITION(false) << "Normalized format does not exist.";
+                return wgpu::VertexFormat::Float32x3;
+        }
+    }
+    switch (type) {
+        // Single Component Types
+        // There is no direct alternative for SSCALED in webgpu. Convert them to Float32 directly.
+        // This will result in increased memory on the cpu side.
+        // TODO: Is Float16 acceptable instead with some potential accuracy errors?
+        case ElementType::BYTE: return integer ? wgpu::VertexFormat::Sint8 : wgpu::VertexFormat::Float32;
+        case ElementType::UBYTE: return integer ? wgpu::VertexFormat::Uint8 : wgpu::VertexFormat::Float32;
+        case ElementType::SHORT: return integer ? wgpu::VertexFormat::Sint16 : wgpu::VertexFormat::Float32;
+        case ElementType::USHORT: return integer ? wgpu::VertexFormat::Uint16 : wgpu::VertexFormat::Float32;
+        case ElementType::HALF: return wgpu::VertexFormat::Float16;
+        case ElementType::INT: return wgpu::VertexFormat::Sint32;
+        case ElementType::UINT: return wgpu::VertexFormat::Uint32;
+        case ElementType::FLOAT: return wgpu::VertexFormat::Float32;
+        // Two Component Types
+        case ElementType::BYTE2: return integer ? wgpu::VertexFormat::Sint8x2 : wgpu::VertexFormat::Float32x2;
+        case ElementType::UBYTE2: return integer ? wgpu::VertexFormat::Uint8x2 : wgpu::VertexFormat::Float32x2;
+        case ElementType::SHORT2: return integer ? wgpu::VertexFormat::Sint16x2 : wgpu::VertexFormat::Float32x2;
+        case ElementType::USHORT2: return integer ? wgpu::VertexFormat::Uint16x2 : wgpu::VertexFormat::Float32x2;
+        case ElementType::HALF2: return wgpu::VertexFormat::Float16x2;
+        case ElementType::FLOAT2: return wgpu::VertexFormat::Float32x2;
+        // Three Component Types
+        case ElementType::BYTE3: return wgpu::VertexFormat::Sint8x4;      // NOT MINSPEC
+        case ElementType::UBYTE3: return wgpu::VertexFormat::Uint8x4;     // NOT MINSPEC
+        case ElementType::SHORT3: return wgpu::VertexFormat::Sint16x4;  // NOT MINSPEC
+        case ElementType::USHORT3: return wgpu::VertexFormat::Uint16x4; // NOT MINSPEC
+        case ElementType::HALF3: return wgpu::VertexFormat::Float16x4; // NOT MINSPEC
+        case ElementType::FLOAT3: return wgpu::VertexFormat::Float32x3;
+        // Four Component Types
+        case ElementType::BYTE4: return integer ? wgpu::VertexFormat::Sint8x4 : wgpu::VertexFormat::Float32x4;
+        case ElementType::UBYTE4: return integer ? wgpu::VertexFormat::Uint8x4 : wgpu::VertexFormat::Float32x4;
+        case ElementType::SHORT4: return integer ? wgpu::VertexFormat::Sint16x4 : wgpu::VertexFormat::Float32x4;
+        case ElementType::USHORT4: return integer ? wgpu::VertexFormat::Uint16x4 : wgpu::VertexFormat::Float32x4;
+        case ElementType::HALF4: return wgpu::VertexFormat::Float16x4;
+        case ElementType::FLOAT4: return wgpu::VertexFormat::Float32x4;
+    }
+    FILAMENT_CHECK_POSTCONDITION(false) << "Vertex format should always be defined.";
+    return wgpu::VertexFormat::Float32x3;
+}
+
+} // namespace
+
 namespace filament::backend {
 
-WGPUVertexBuffer::WGPUVertexBuffer(uint32_t vextexCount, uint32_t bufferCount,
-        Handle<WGPUVertexBufferInfo> vbih)
-    : HwVertexBuffer(vextexCount),
-      vbih(vbih),
-      buffers(MAX_VERTEX_BUFFER_COUNT) {}
+WGPUVertexBufferInfo::WGPUVertexBufferInfo(uint8_t bufferCount, uint8_t attributeCount,
+        AttributeArray const& attributes)
+    : HwVertexBufferInfo(bufferCount, attributeCount),
+      mVertexBufferLayout(bufferCount),
+      mAttributes(bufferCount) {
+    for (uint32_t attribIndex = 0; attribIndex < attributes.size(); attribIndex++) {
+        Attribute attrib = attributes[attribIndex];
+        // Ignore the attributes which are not bind to vertex buffers.
+        if (attrib.buffer == Attribute::BUFFER_UNUSED) {
+            continue;
+        }
+
+        assert_invariant(attrib.buffer < bufferCount);
+        bool const isInteger = attrib.flags & Attribute::FLAG_INTEGER_TARGET;
+        bool const isNormalized = attrib.flags & Attribute::FLAG_NORMALIZED;
+        wgpu::VertexFormat vertexFormat = getVertexFormat(attrib.type, isNormalized, isInteger);
+
+        mAttributes[attrib.buffer].push_back({
+            .format = vertexFormat,
+            .offset = attrib.offset,
+            .shaderLocation = attribIndex,
+        });
+        mVertexBufferLayout[attrib.buffer] = {
+            .arrayStride = attrib.stride,
+        };
+    }
+
+    for (uint32_t bufferIndex = 0; bufferIndex < bufferCount; bufferIndex++) {
+        mVertexBufferLayout[bufferIndex] = {
+            .attributeCount = mAttributes[bufferIndex].size(),
+            .attributes = mAttributes[bufferIndex].data(),
+        };
+    }
+}
+
+WGPUIndexBuffer::WGPUIndexBuffer(wgpu::Device const& device, uint8_t elementSize,
+        uint32_t indexCount)
+    : buffer(createIndexBuffer(device, elementSize, indexCount)),
+      indexFormat(elementSize == 2 ? wgpu::IndexFormat::Uint16 : wgpu::IndexFormat::Uint32) {}
+
+
+WGPUVertexBuffer::WGPUVertexBuffer(wgpu::Device const &device, uint32_t vextexCount, uint32_t bufferCount,
+                                   Handle<HwVertexBufferInfo> vbih)
+        : HwVertexBuffer(vextexCount),
+          vbih(vbih),
+          buffers(bufferCount) {
+    wgpu::BufferDescriptor descriptor {
+            .usage = wgpu::BufferUsage::CopyDst | wgpu::BufferUsage::Vertex,
+            .size = vextexCount * bufferCount,
+            .mappedAtCreation = false };
+
+    for (uint32_t i = 0; i < bufferCount; ++i) {
+        descriptor.label = ("vertex_buffer_" + std::to_string(i)).c_str();
+        buffers[i] = device.CreateBuffer(&descriptor);
+    }
+}
 
 // TODO: Empty function is a place holder for verxtex buffer updates and should be
 // updated for that purpose.
@@ -31,4 +168,100 @@ void WGPUVertexBuffer::setBuffer(WGPUBufferObject* bufferObject, uint32_t index)
 WGPUBufferObject::WGPUBufferObject(BufferObjectBinding bindingType, uint32_t byteCount)
     : HwBufferObject(byteCount),
       bufferObjectBinding(bindingType) {}
+
+wgpu::ShaderStage WebGPUDescriptorSetLayout::filamentStageToWGPUStage(ShaderStageFlags fFlags) {
+    wgpu::ShaderStage retStages = wgpu::ShaderStage::None;
+    if (any(ShaderStageFlags::VERTEX & fFlags)) {
+        retStages |= wgpu::ShaderStage::Vertex;
+    }
+    if (any(ShaderStageFlags::FRAGMENT & fFlags)) {
+        retStages |= wgpu::ShaderStage::Fragment;
+    }
+    if (any(ShaderStageFlags::COMPUTE & fFlags)) {
+        retStages |= wgpu::ShaderStage::Compute;
+    }
+    return retStages;
+}
+
+WebGPUDescriptorSetLayout::WebGPUDescriptorSetLayout(DescriptorSetLayout const& layout,
+        wgpu::Device const* device) {
+    assert_invariant(device->Get());
+
+    // TODO: layoutDescriptor has a "Label". Ideally we can get info on what this layout is for
+    // debugging. For now, hack an incrementing value.
+    static int layoutNum = 0;
+
+
+    uint samplerCount =
+            std::count_if(layout.bindings.begin(), layout.bindings.end(), [](auto& fEntry) {
+                return fEntry.type == DescriptorType::SAMPLER ||
+                       fEntry.type == DescriptorType::SAMPLER_EXTERNAL;
+            });
+
+
+    std::vector<wgpu::BindGroupLayoutEntry> wEntries;
+    wEntries.reserve(layout.bindings.size() + samplerCount);
+
+    for (auto fEntry: layout.bindings) {
+        auto& wEntry = wEntries.emplace_back();
+        wEntry.visibility = filamentStageToWGPUStage(fEntry.stageFlags);
+        wEntry.binding = fEntry.binding * 2;
+
+        switch (fEntry.type) {
+            // TODO Metal treats these the same. Is this fine?
+            case DescriptorType::SAMPLER_EXTERNAL:
+            case DescriptorType::SAMPLER: {
+                // Sampler binding is 2n+1 due to split.
+                auto& samplerEntry = wEntries.emplace_back();
+                samplerEntry.binding = fEntry.binding * 2 + 1;
+                samplerEntry.visibility = wEntry.visibility;
+                // We are simply hoping that undefined and defaults suffices here.
+                samplerEntry.sampler.type = wgpu::SamplerBindingType::Undefined;
+                wEntry.texture.sampleType = wgpu::TextureSampleType::Undefined;
+                break;
+            }
+            case DescriptorType::UNIFORM_BUFFER: {
+                wEntry.buffer.hasDynamicOffset =
+                        any(fEntry.flags & DescriptorFlags::DYNAMIC_OFFSET);
+                wEntry.buffer.type = wgpu::BufferBindingType::Uniform;
+                // TODO: Ideally we fill minBindingSize
+                break;
+            }
+
+            case DescriptorType::INPUT_ATTACHMENT: {
+                // TODO: support INPUT_ATTACHMENT. Metal does not currently.
+                PANIC_POSTCONDITION("Input Attachment is not supported");
+                break;
+            }
+
+            case DescriptorType::SHADER_STORAGE_BUFFER: {
+                // TODO: Vulkan does not support this, can we?
+                PANIC_POSTCONDITION("Shader storage is not supported");
+                break;
+            }
+        }
+
+        // Currently flags are only used to specify dynamic offset.
+
+        // UNUSED
+        // fEntry.count
+    }
+
+    wgpu::BindGroupLayoutDescriptor layoutDescriptor{
+        // TODO: layoutDescriptor has a "Label". Ideally we can get info on what this layout is for
+        // debugging. For now, hack an incrementing value.
+        .label{ "layout_" + std::to_string(++layoutNum) },
+        .entryCount = wEntries.size(),
+        .entries = wEntries.data()
+    };
+    // TODO Do we need to defer this until we have more info on textures and samplers??
+    mLayout = device->CreateBindGroupLayout(&layoutDescriptor);
+}
+WebGPUDescriptorSetLayout::~WebGPUDescriptorSetLayout() {}
+
+void WGPURenderPrimitive::setBuffers(WGPUVertexBufferInfo const* const vbi,
+        WGPUVertexBuffer* vertexBuffer, WGPUIndexBuffer* indexBuffer) {
+
+    }
+
 }// namespace filament::backend

filament/backend/src/webgpu/WebGPUHandles.h

@@ -24,6 +24,7 @@
 #include <backend/Handle.h>
 
 #include <utils/FixedCapacityVector.h>
+// #include <utils/StructureOfArrays.h>
 
 #include <webgpu/webgpu_cpp.h>
 
@@ -32,35 +33,52 @@
 namespace filament::backend {
 
 struct WGPUBufferObject;
-// TODO: Currently WGPUVertexBufferInfo is not used by WebGPU for useful task.
-// Update the struct when used by WebGPU driver.
+
+// VertexBufferInfo contains layout info for Vertex Buffer based on WebGPU structs. In WebGPU each
+// VertexBufferLayout is associated with a single vertex buffer. So number of mVertexBufferLayout
+// is equal to bufferCount. Each VertexBufferLayout can contain multiple VertexAttribute. Bind index
+// of vertex buffer is implicitly calculated by the position of VertexBufferLayout in an array.
 struct WGPUVertexBufferInfo : public HwVertexBufferInfo {
+
     WGPUVertexBufferInfo(uint8_t bufferCount, uint8_t attributeCount,
-            AttributeArray const& attributes)
-        : HwVertexBufferInfo(bufferCount, attributeCount),
-          attributes(attributes) {}
-    AttributeArray attributes;
+            AttributeArray const& attributes);
+    inline  wgpu::VertexBufferLayout const* getVertexBufferLayout() const {
+        return mVertexBufferLayout.data();
+    }
+    inline uint32_t getVertexBufferLayoutSize() const {
+        return mVertexBufferLayout.size();
+    }
+
+    inline wgpu::VertexAttribute const* getVertexAttributeForIndex(uint32_t index) const {
+        return mAttributes[index].data();
+    }
+    inline uint32_t getVertexAttributeSize(uint32_t index) const {
+        return mAttributes[index].size();
+    }
+private:
+    std::vector<wgpu::VertexBufferLayout> mVertexBufferLayout;
+    std::vector<std::vector<wgpu::VertexAttribute>> mAttributes;
 };
 
-// TODO: Currently WGPUVertexBuffer is not used by WebGPU for useful task.
-// Update the struct when used by WebGPU driver.
 struct WGPUVertexBuffer : public HwVertexBuffer {
-    WGPUVertexBuffer(uint32_t vextexCount, uint32_t bufferCount, Handle<WGPUVertexBufferInfo> vbih);
-    void setBuffer(WGPUBufferObject* bufferObject, uint32_t index);
+    WGPUVertexBuffer(wgpu::Device const &device, uint32_t vextexCount, uint32_t bufferCount,
+                     Handle<HwVertexBufferInfo> vbih);
 
-    Handle<WGPUVertexBufferInfo> vbih;
+    void setBuffer(WGPUBufferObject *bufferObject, uint32_t index);
+
+    Handle<HwVertexBufferInfo> vbih;
     utils::FixedCapacityVector<wgpu::Buffer> buffers;
 };
 
-// TODO: Currently WGPUIndexBuffer is not used by WebGPU for useful task.
-// Update the struct when used by WebGPU driver.
 struct WGPUIndexBuffer : public HwIndexBuffer {
-    WGPUIndexBuffer(BufferUsage usage, uint8_t elementSize, uint32_t indexCount);
+    WGPUIndexBuffer(wgpu::Device const &device, uint8_t elementSize,
+                    uint32_t indexCount);
 
     wgpu::Buffer buffer;
+    wgpu::IndexFormat indexFormat;
 };
 
-// TODO: Currently WGPUVertexBufferInfo is not used by WebGPU for useful task.
+// TODO: Currently WGPUBufferObject is not used by WebGPU for useful task.
 // Update the struct when used by WebGPU driver.
 struct WGPUBufferObject : HwBufferObject {
     WGPUBufferObject(BufferObjectBinding bindingType, uint32_t byteCount);
@@ -69,6 +87,19 @@ struct WGPUBufferObject : HwBufferObject {
     const BufferObjectBinding bufferObjectBinding;
 };
 
+class WebGPUDescriptorSetLayout : public HwDescriptorSetLayout {
+public:
+    WebGPUDescriptorSetLayout(DescriptorSetLayout const& layout, wgpu::Device const* device);
+    ~WebGPUDescriptorSetLayout();
+
+private:
+    // TODO: If this is useful elsewhere, remove it from this class
+    // Convert Filament Shader Stage Flags bitmask to webgpu equivilant
+    static wgpu::ShaderStage filamentStageToWGPUStage(ShaderStageFlags fFlags);
+
+    wgpu::BindGroupLayout mLayout;
+};
+
 // TODO: Currently WGPUTexture is not used by WebGPU for useful task.
 // Update the struct when used by WebGPU driver.
 struct WGPUTexture : public HwTexture {
@@ -81,6 +112,16 @@ struct WGPUTexture : public HwTexture {
     wgpu::Texture texture = nullptr;
 };
 
+struct WGPURenderPrimitive : public HwRenderPrimitive {
+    WGPURenderPrimitive();
+
+    void setBuffers(WGPUVertexBufferInfo const* const vbi,
+            WGPUVertexBuffer* vertexBuffer, WGPUIndexBuffer* indexBuffer);
+
+    WGPUVertexBuffer* vertexBuffer = nullptr;
+    WGPUIndexBuffer* indexBuffer = nullptr;
+};
+
 // TODO: Currently WGPURenderTarget is not used by WebGPU for useful task.
 // Update the struct when used by WebGPU driver.
 struct WGPURenderTarget : public HwRenderTarget {

filament/backend/src/webgpu/WebGPUSwapChain.cpp

@@ -191,9 +191,12 @@ wgpu::CompositeAlphaMode selectAlphaMode(size_t availableAlphaModesCount,
 }
 
 void initConfig(wgpu::SurfaceConfiguration& config, wgpu::Device const& device,
-        wgpu::SurfaceCapabilities const& capabilities, bool useSRGBColorSpace) {
+        wgpu::SurfaceCapabilities const& capabilities, wgpu::Extent2D const& surfaceSize,
+        bool useSRGBColorSpace) {
     config.device = device;
     config.usage = wgpu::TextureUsage::RenderAttachment;
+    config.width = surfaceSize.width;
+    config.height = surfaceSize.height;
     config.format =
             selectColorFormat(capabilities.formatCount, capabilities.formats, useSRGBColorSpace);
     config.presentMode =
@@ -205,8 +208,8 @@ void initConfig(wgpu::SurfaceConfiguration& config, wgpu::Device const& device,
 
 namespace filament::backend {
 
-WebGPUSwapChain::WebGPUSwapChain(wgpu::Surface&& surface, wgpu::Adapter& adapter,
-        wgpu::Device& device, uint64_t flags)
+WebGPUSwapChain::WebGPUSwapChain(wgpu::Surface&& surface, wgpu::Extent2D const& surfaceSize,
+        wgpu::Adapter& adapter, wgpu::Device& device, uint64_t flags)
     : mSurface(surface) {
     wgpu::SurfaceCapabilities capabilities = {};
     if (!mSurface.GetCapabilities(adapter, &capabilities)) {
@@ -217,43 +220,42 @@ WebGPUSwapChain::WebGPUSwapChain(wgpu::Surface&& surface, wgpu::Adapter& adapter
 #endif
     }
     const bool useSRGBColorSpace = (flags & SWAP_CHAIN_CONFIG_SRGB_COLORSPACE) != 0;
-    initConfig(mConfig, device, capabilities, useSRGBColorSpace);
+    initConfig(mConfig, device, capabilities, surfaceSize, useSRGBColorSpace);
+    mSurface.Configure(&mConfig);
 }
 
 WebGPUSwapChain::~WebGPUSwapChain() {
-    if (mConfigured) {
-        mSurface.Unconfigure();
-        mConfigured = false;
-    }
+    mSurface.Unconfigure();
 }
 
-void WebGPUSwapChain::getCurrentTexture(uint32_t width, uint32_t height, wgpu::SurfaceTexture* texture) {
-    if (width < 1 || height < 1) {
-        PANIC_LOG("WebGPUSwapChain::GetCurrentTexture: Invalid width and/or height requested.");
-        return;
-    }
-    if (mConfig.width != width || mConfig.height != height || !mConfigured) {
-        mConfig.width = width;
-        mConfig.height = height;
+void WebGPUSwapChain::setExtent(wgpu::Extent2D const& currentSurfaceSize) {
+    FILAMENT_CHECK_POSTCONDITION(currentSurfaceSize.width > 0 || currentSurfaceSize.height > 0)
+            << "WebGPUSwapChain::setExtent: Invalid width " << currentSurfaceSize.width
+            << " and/or height " << currentSurfaceSize.height << " requested.";
+    if (mConfig.width != currentSurfaceSize.width || mConfig.height != currentSurfaceSize.height) {
+        mConfig.width = currentSurfaceSize.width;
+        mConfig.height = currentSurfaceSize.height;
 #if FWGPU_ENABLED(FWGPU_PRINT_SYSTEM)
         printSurfaceConfiguration(mConfig);
 #endif
+        FWGPU_LOGD << "Resizing to width " << mConfig.width << " height " << mConfig.height
+                   << utils::io::endl;
+        // TODO we may need to ensure no surface texture is flight when we do this. some
+        //      synchronization may be necessary
         mSurface.Configure(&mConfig);
-        mConfigured = true;
     }
-
-    mSurface.GetCurrentTexture(texture);
 }
 
-wgpu::TextureView WebGPUSwapChain::getNextSurfaceTextureView(uint32_t width, uint32_t height) {
+wgpu::TextureView WebGPUSwapChain::getCurrentSurfaceTextureView(
+        wgpu::Extent2D const& currentSurfaceSize) {
+    setExtent(currentSurfaceSize);
     wgpu::SurfaceTexture surfaceTexture;
-    getCurrentTexture(width, height, &surfaceTexture);
+    mSurface.GetCurrentTexture(&surfaceTexture);
     if (surfaceTexture.status != wgpu::SurfaceGetCurrentTextureStatus::SuccessOptimal) {
         return nullptr;
     }
-
     // Create a view for this surface texture
-    //TODO: review these initiliazations as webgpu pipeline gets mature
+    // TODO: review these initiliazations as webgpu pipeline gets mature
     wgpu::TextureViewDescriptor textureViewDescriptor = {
         .label = "texture_view",
         .format = surfaceTexture.texture.GetFormat(),

filament/backend/src/webgpu/WebGPUSwapChain.h

@@ -19,26 +19,28 @@
 
 #include <webgpu/webgpu_cpp.h>
 
+#include "DriverBase.h"
 #include <backend/Platform.h>
 
 #include <cstdint>
 
 namespace filament::backend {
 
-class WebGPUSwapChain : public Platform::SwapChain {
+class WebGPUSwapChain final : public Platform::SwapChain, HwSwapChain {
 public:
-    WebGPUSwapChain(wgpu::Surface&& surface, wgpu::Adapter& adapter, wgpu::Device& device,
-            uint64_t flags);
+    WebGPUSwapChain(wgpu::Surface&& surface, wgpu::Extent2D const& surfaceSize,
+            wgpu::Adapter& adapter, wgpu::Device& device, uint64_t flags);
     ~WebGPUSwapChain();
 
-    wgpu::TextureView getNextSurfaceTextureView(uint32_t width, uint32_t height);
+    wgpu::TextureView getCurrentSurfaceTextureView(wgpu::Extent2D const&);
+
     void present();
 
 private:
-    void getCurrentTexture(uint32_t width, uint32_t height, wgpu::SurfaceTexture*);
+    void setExtent(wgpu::Extent2D const&);
+
     wgpu::Surface mSurface = {};
     wgpu::SurfaceConfiguration mConfig = {};
-    bool mConfigured = false;
 };
 
 } // namespace filament::backend

filament/backend/src/webgpu/platform/WebGPUPlatformAndroid.cpp

@@ -18,6 +18,7 @@
 
 #include <utils/Panic.h>
 
+#include <android/native_window.h>
 #include <webgpu/webgpu_cpp.h>
 
 #include <cstdint>
@@ -28,6 +29,14 @@
 
 namespace filament::backend {
 
+wgpu::Extent2D WebGPUPlatform::getSurfaceExtent(void* nativeWindow) const {
+    ANativeWindow* window = static_cast<ANativeWindow*>(nativeWindow);
+    return wgpu::Extent2D{
+        .width = static_cast<uint32_t>(ANativeWindow_getWidth(window)),
+        .height = static_cast<uint32_t>(ANativeWindow_getHeight(window))
+    };
+}
+
 wgpu::Surface WebGPUPlatform::createSurface(void* nativeWindow, uint64_t /*flags*/) {
     wgpu::SurfaceSourceAndroidNativeWindow surfaceSourceAndroidWindow{};
     surfaceSourceAndroidWindow.window = nativeWindow;

filament/backend/src/webgpu/platform/WebGPUPlatformApple.mm

@@ -33,6 +33,15 @@
 
 namespace filament::backend {
 
+wgpu::Extent2D WebGPUPlatform::getSurfaceExtent(void* nativeWindow) const {
+    // Both IOS and MacOS expects CAMetalLayer.
+    CAMetalLayer* metalLayer = (__bridge CAMetalLayer*) nativeWindow;
+    return wgpu::Extent2D{
+        .width = static_cast<uint32_t>(metalLayer.drawableSize.width),
+        .height = static_cast<uint32_t>(metalLayer.drawableSize.height)
+    };
+}
+
 wgpu::Surface WebGPUPlatform::createSurface(void* nativeWindow, uint64_t /*flags*/) {
     wgpu::Surface surface = nullptr;
     // Both IOS and MacOS expects CAMetalLayer.

filament/backend/src/webgpu/platform/WebGPUPlatformLinux.cpp

@@ -79,6 +79,74 @@
 
 namespace filament::backend {
 
+wgpu::Extent2D WebGPUPlatform::getSurfaceExtent(void* nativeWindow) const {
+    auto surfaceExtent = wgpu::Extent2D{};
+#if defined(__linux__) && defined(FILAMENT_SUPPORTS_WAYLAND)
+    wl* ptrval = reinterpret_cast<wl*>(nativeWindow);
+    surfaceExtent.width = ptrval->width;
+    surfaceExtent.height = ptrval->height;
+    FILAMENT_CHECK_POSTCONDITION(surfaceExtent.width != 0 && surfaceExtent.height != 0)
+            << "Unable to get window size for Linux Wayland-backed surface.";
+#elif defined(LINUX_OR_FREEBSD) && defined(FILAMENT_SUPPORTS_X11)
+    if (g_x11.library == nullptr) {
+        g_x11.library = dlopen(LIBRARY_X11, RTLD_LOCAL | RTLD_NOW);
+        FILAMENT_CHECK_PRECONDITION(g_x11.library) << "Unable to open X11 library.";
+        #if defined(FILAMENT_SUPPORTS_XCB)
+            g_x11.xcbConnect = (XCB_CONNECT) dlsym(g_x11.library, "xcb_connect");
+            int screen = 0;
+            g_x11.connection = g_x11.xcbConnect(nullptr, &screen);
+        #endif
+        #if defined(FILAMENT_SUPPORTS_XLIB)
+            g_x11.openDisplay = (X11_OPEN_DISPLAY) dlsym(g_x11.library, "XOpenDisplay");
+            g_x11.display = g_x11.openDisplay(NULL);
+            FILAMENT_CHECK_PRECONDITION(g_x11.display) << "Unable to open X11 display.";
+        #endif
+    }
+    #if defined(FILAMENT_SUPPORTS_XCB) || defined(FILAMENT_SUPPORTS_XLIB)
+        bool useXcb = false;
+    #endif
+    #if defined(FILAMENT_SUPPORTS_XCB)
+        #if defined(FILAMENT_SUPPORTS_XLIB)
+            useXcb = (SWAP_CHAIN_CONFIG_ENABLE_XCB) != 0;
+        #else
+            useXcb = true;
+        #endif
+        if (useXcb) {
+            const xcb_setup_t* setup = xcb_get_setup(g_x11.connection);
+            xcb_screen_iterator_t screen_iter = xcb_setup_roots_iterator(setup);
+            xcb_screen_t* screen = screen_iter.data;
+            surfaceExtent.width = static_cast<uint32_t>(screen->width_in_pixels);
+            surfaceExtent.height = static_cast<uint32_t>(screen->height_in_pixels);
+            FILAMENT_CHECK_POSTCONDITION(surfaceExtent.width != 0 && surfaceExtent.height != 0)
+                    << "Unable to get window surface size for Linux (or FreeBSD) "
+                       "XCB-backed surface.";
+        }
+    #endif
+    #if defined(FILAMENT_SUPPORTS_XLIB)
+        if (!useXcb) {
+            int screenNumber = DefaultScreen(g_x11.display);
+            Screen* screen = ScreenOfDisplay(g_x11.display, screenNumber);
+            surfaceExtent.width = static_cast<uint32_t>(WidthOfScreen(screen));
+            surfaceExtent.height = static_cast<uint32_t>(HeightOfScreen(screen));
+            FILAMENT_CHECK_POSTCONDITION(surfaceExtent.width != 0 && surfaceExtent.height != 0)
+                    << "Unable to get window surface size for Linux (or FreeBSD) "
+                       "XLib-backed surface.";
+        }
+    #endif
+    FILAMENT_CHECK_POSTCONDITION(surfaceExtent.width != 0 && surfaceExtent.height != 0)
+            << "Cannot get window surface size for X11 surface for Linux (or FreeBSD) OS "
+               "(not built with support for XCB or XLIB?)";
+#elif defined(__linux__)
+    FILAMENT_CHECK_POSTCONDITION(surfaceExtent.width != 0 && surfaceExtent.height != 0)
+            << "Cannot get window surface size for Linux (or FreeBSD) OS "
+               "(not built with support for Wayland or X11?)";
+#else
+    FILAMENT_CHECK_POSTCONDITION(surfaceExtent.width != 0 && surfaceExtent.height != 0)
+            << "Not a supported (Linux) OS + WebGPU platform";
+#endif
+    return surfaceExtent;
+}
+
 wgpu::Surface WebGPUPlatform::createSurface(void* nativeWindow, uint64_t flags) {
     wgpu::Surface surface = nullptr;
 #if defined(__linux__) && defined(FILAMENT_SUPPORTS_WAYLAND)

filament/backend/src/webgpu/platform/WebGPUPlatformWindows.cpp

@@ -30,6 +30,16 @@
 
 namespace filament::backend {
 
+wgpu::Extent2D WebGPUPlatform::getSurfaceExtent(void* nativeWindow) const {
+    HWND window = static_cast<HWND>(nativeWindow);
+    RECT windowRect;
+    GetWindowRect(window, &windowRect);
+    return wgpu::Extent2D{
+        .width = static_cast<uint32_t>(windowRect.right - windowRect.left),
+        .height = static_cast<uint32_t>(windowRect.bottom - windowRect.top)
+    };
+}
+
 wgpu::Surface WebGPUPlatform::createSurface(void* nativeWindow, uint64_t /*flags*/) {
     // TODO verify this is necessary for Dawn implementation as well:
     // On (at least) NVIDIA drivers, the Vulkan implementation (specifically the call to

filament/backend/test/BackendTest.cpp

@@ -43,10 +43,12 @@ using namespace image;
 namespace test {
 
 Backend BackendTest::sBackend = Backend::NOOP;
+OperatingSystem BackendTest::sOperatingSystem = OperatingSystem::OTHER;
 bool BackendTest::sIsMobilePlatform = false;
 
-void BackendTest::init(Backend backend, bool isMobilePlatform) {
+void BackendTest::init(Backend backend, OperatingSystem operatingSystem, bool isMobilePlatform) {
     sBackend = backend;
+    sOperatingSystem = operatingSystem;
     sIsMobilePlatform = isMobilePlatform;
 }
 
@@ -199,6 +201,18 @@ void BackendTest::readPixelsAndAssertHash(const char* testName, size_t width, si
     getDriverApi().readPixels(rt, 0, 0, width, height, std::move(pbd));
 }
 
+bool BackendTest::matchesEnvironment(Backend backend) {
+    return sBackend == backend;
+}
+
+bool BackendTest::matchesEnvironment(OperatingSystem operatingSystem) {
+    return sOperatingSystem == operatingSystem;
+}
+
+bool BackendTest::matchesEnvironment(OperatingSystem operatingSystem, Backend backend) {
+    return matchesEnvironment(operatingSystem) && matchesEnvironment(backend);
+}
+
 class Environment : public ::testing::Environment {
 public:
     virtual void SetUp() override {
@@ -210,8 +224,8 @@ public:
     }
 };
 
-void initTests(Backend backend, bool isMobile, int& argc, char* argv[]) {
-    BackendTest::init(backend, isMobile);
+void initTests(Backend backend, OperatingSystem operatingSystem, bool isMobile, int& argc, char* argv[]) {
+    BackendTest::init(backend, operatingSystem, isMobile);
     ::testing::InitGoogleTest(&argc, argv);
     ::testing::AddGlobalTestEnvironment(new Environment);
 }

filament/backend/test/BackendTest.h

@@ -31,9 +31,10 @@ namespace test {
 class BackendTest : public ::testing::Test {
 public:
 
-    static void init(Backend backend, bool isMobilePlatform);
+    static void init(Backend backend, OperatingSystem operatingSystem, bool isMobilePlatform);
 
     static Backend sBackend;
+    static OperatingSystem sOperatingSystem;
     static bool sIsMobilePlatform;
 
 protected:
@@ -71,6 +72,10 @@ protected:
     filament::backend::DriverApi& getDriverApi() { return *commandStream; }
     filament::backend::Driver& getDriver() { return *driver; }
 
+    static bool matchesEnvironment(Backend backend);
+    static bool matchesEnvironment(OperatingSystem operatingSystem);
+    static bool matchesEnvironment(OperatingSystem operatingSystem, Backend backend);
+
 private:
 
     filament::backend::Driver* driver = nullptr;

filament/backend/test/PlatformRunner.cpp

@@ -0,0 +1,60 @@
+/*
+ * Copyright (C) 2019 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 "PlatformRunner.h"
+
+namespace utils {
+
+template<>
+CString to_string<test::Backend>(test::Backend backend) noexcept {
+    switch (backend) {
+        case test::Backend::OPENGL: {
+            return "OpenGL";
+        }
+        case test::Backend::VULKAN: {
+            return "Vulkan";
+        }
+        case test::Backend::METAL: {
+            return "Metal";
+        }
+        case test::Backend::WEBGPU: {
+            return "WebGPU";
+        }
+        case test::Backend::NOOP:
+        default: {
+            return "No-op";
+        }
+    }
+}
+
+template<>
+CString to_string(test::OperatingSystem os) noexcept {
+    switch (os) {
+        case test::OperatingSystem::LINUX: {
+            return "Linux";
+        }
+        case test::OperatingSystem::APPLE: {
+            return "Apple";
+        }
+        case test::OperatingSystem::OTHER:
+        default: {
+            return "Other";
+        }
+    }
+}
+
+} // namespace utils
+

filament/backend/test/PlatformRunner.h

@@ -19,6 +19,7 @@
 
 #include <stdint.h>
 #include <stddef.h>
+#include "utils/CString.h"
 
 namespace test {
 
@@ -34,6 +35,15 @@ enum class Backend : uint8_t {
     NOOP = 5,
 };
 
+enum class OperatingSystem: uint8_t {
+    OTHER = 1,
+    // Also represents android phones.
+    LINUX = 2,
+    // Also represents iOS phones.
+    APPLE = 3,
+    // TODO: When tests support windows add it here.
+};
+
 struct NativeView {
     void* ptr = nullptr;
     size_t width = 0, height = 0;
@@ -51,9 +61,10 @@ NativeView getNativeView();
  * No tests will be run yet.
  *
  * @param backend The backend to run the tests on.
+ * @param operatingSystem The operating system the tests are being run on.
  * @param isMobile True if the platform is a mobile platform (iOS or Android).
  */
-void initTests(Backend backend, bool isMobile, int& argc, char* argv[]);
+void initTests(Backend backend, OperatingSystem operatingSystem, bool isMobile, int& argc, char* argv[]);
 
 /**
  * Test runners should call runTests when they are ready for tests to be run.
@@ -68,6 +79,6 @@ int runTests();
  */
 Backend parseArgumentsForBackend(int argc, char* argv[]);
 
-}
+} // namespace test
 
 #endif

filament/backend/test/Skip.cpp

@@ -0,0 +1,96 @@
+/*
+ * Copyright (C) 2025 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "Skip.h"
+
+#include <sstream>
+
+namespace test {
+
+SkipEnvironment::SkipEnvironment(test::Backend backend) : backend(backend) {}
+SkipEnvironment::SkipEnvironment(test::OperatingSystem os) : os(os) {}
+SkipEnvironment::SkipEnvironment(test::OperatingSystem os, test::Backend backend)
+    : backend(backend),
+      os(os) {}
+
+bool SkipEnvironment::matches() {
+    bool backendMatches = !backend.has_value() || *backend == BackendTest::sBackend;
+    bool osMatches = !os.has_value() || *os == BackendTest::sOperatingSystem;
+    bool isMobileMatches = !isMobile.has_value() || *isMobile == BackendTest::sIsMobilePlatform;
+    return backendMatches && osMatches && isMobileMatches;
+}
+
+std::string SkipEnvironment::describe() {
+    std::stringstream result;
+    if (matches()) {
+        result << "environment matches because " << describe_actual_environment() << ".";
+    } else {
+        result << "environment does not match because " << describe_requirements() << " but "
+               << describe_actual_environment() << ".";
+    }
+    return result.str();
+}
+
+std::string SkipEnvironment::describe_actual_environment() {
+    bool resultWritten = false;
+    std::stringstream reality;
+    if (backend.has_value()) {
+        reality << "backend was " << utils::to_string(BackendTest::sBackend).c_str();
+        resultWritten = true;
+    }
+    if (os.has_value()) {
+        if (resultWritten) {
+            reality << ", and ";
+        }
+        reality << "operating system was "
+                << utils::to_string(BackendTest::sOperatingSystem).c_str();
+        resultWritten = true;
+    }
+    if (isMobile.has_value()) {
+        if (resultWritten) {
+            reality << ", and ";
+        }
+        reality << "device " << (BackendTest::sIsMobilePlatform ? "was" : "was not") << " mobile";
+        resultWritten = true;
+    }
+    return reality.str();
+}
+
+std::string SkipEnvironment::describe_requirements() {
+    bool resultWritten = false;
+    std::stringstream requirement;
+    if (backend.has_value()) {
+        requirement << "backend needs to be " << utils::to_string(*backend).c_str();
+        resultWritten = true;
+    }
+    if (os.has_value()) {
+        if (resultWritten) {
+            requirement << ", and ";
+        }
+        requirement << "operating system needs to be " << utils::to_string(*os).c_str();
+        resultWritten = true;
+    }
+    if (isMobile.has_value() && BackendTest::sIsMobilePlatform != isMobile) {
+        if (resultWritten) {
+            requirement << ", and ";
+        }
+        requirement << "device needs to " << (*isMobile ? "be" : "not be") << " mobile";
+        resultWritten = true;
+    }
+    return requirement.str();
+}
+
+} // namespace test

filament/backend/test/Skip.h

@@ -0,0 +1,55 @@
+/*
+ * Copyright (C) 2025 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef TNT_SKIP_H
+#define TNT_SKIP_H
+
+#include <gtest/gtest.h>
+#include "BackendTest.h"
+
+// skipEnvironment must be a test::SkipEnvironment
+#define SKIP_IF(skipEnvironment)                                                                   \
+do {                                                                                               \
+    SkipEnvironment skip(skipEnvironment);                                                         \
+    if (skip.matches()) {                                                                          \
+        GTEST_SKIP() << "Skipping test as the " << skip.describe();                                \
+    }                                                                                              \
+} while (false)
+
+namespace test {
+
+struct SkipEnvironment {
+    SkipEnvironment(const SkipEnvironment&) = default;
+    explicit SkipEnvironment(test::Backend backend);
+    explicit SkipEnvironment(test::OperatingSystem os);
+    SkipEnvironment(test::OperatingSystem os, test::Backend backend);
+
+    std::optional<test::Backend> backend;
+    std::optional<test::OperatingSystem> os;
+    std::optional<bool> isMobile;
+
+    bool matches();
+    // Describes the current state of either matching or mismatching.
+    std::string describe();
+    // Describe all the non-null requirements.
+    std::string describe_requirements();
+    // Describes the environment's status for all the attributes that are non-null.
+    std::string describe_actual_environment();
+};
+
+} // namespace test
+
+#endif// TNT_SKIP_H

filament/backend/test/linux_runner.cpp

@@ -51,6 +51,6 @@ int main(int argc, char* argv[]) {
         return 1;
     }
 
-    test::initTests(backend, false, argc, argv);
+    test::initTests(backend, test::OperatingSystem::LINUX, false, argc, argv);
     return test::runTests();
 }

filament/backend/test/mac_runner.mm

@@ -98,7 +98,7 @@ test::NativeView getNativeView() {
 
 int main(int argc, char* argv[]) {
     auto backend = test::parseArgumentsForBackend(argc, argv);
-    test::initTests(backend, false, argc, argv);
+    test::initTests(backend, test::OperatingSystem::APPLE, false, argc, argv);
     AppDelegate* delegate = [AppDelegate new];
     delegate.backend = backend;
     NSApplication* app = [NSApplication sharedApplication];

filament/backend/test/test_Callbacks.cpp

@@ -17,6 +17,7 @@
 #include "BackendTest.h"
 
 #include "Lifetimes.h"
+#include "Skip.h"
 
 using namespace filament;
 using namespace filament::backend;
@@ -24,6 +25,8 @@ using namespace filament::backend;
 namespace test {
 
 TEST_F(BackendTest, FrameScheduledCallback) {
+    SKIP_IF(SkipEnvironment(OperatingSystem::APPLE, Backend::OPENGL));
+
     auto& api = getDriverApi();
     Cleanup cleanup(api);
 
@@ -81,6 +84,8 @@ TEST_F(BackendTest, FrameScheduledCallback) {
 }
 
 TEST_F(BackendTest, FrameCompletedCallback) {
+    SKIP_IF(SkipEnvironment(OperatingSystem::APPLE, Backend::OPENGL));
+
     auto& api = getDriverApi();
     Cleanup cleanup(api);
 

filament/backend/test/test_PushConstants.cpp

@@ -18,6 +18,7 @@
 
 #include "Lifetimes.h"
 #include "ShaderGenerator.h"
+#include "Skip.h"
 #include "TrianglePrimitive.h"
 
 #include <utils/Hash.h>
@@ -78,6 +79,8 @@ void main() {
 })";
 
 TEST_F(BackendTest, PushConstants) {
+    SKIP_IF(SkipEnvironment(OperatingSystem::APPLE, Backend::OPENGL));
+
     auto& api = getDriverApi();
 
     api.startCapture(0);

filament/src/details/MaterialInstance.cpp

@@ -269,12 +269,14 @@ void FMaterialInstance::setParameterImpl(std::string_view const name,
     if (texture && texture->textureHandleCanMutate()) {
         mTextureParameters[binding] = { texture, sampler.getSamplerParams() };
     } else {
+        // Ensure to erase the binding from mTextureParameters since it will not
+        // be updated.
+        mTextureParameters.erase(binding);
+
         Handle<HwTexture> handle{};
         if (texture) {
             handle = texture->getHwHandleForSampling();
             assert_invariant(handle == texture->getHwHandle());
-        } else {
-            mTextureParameters.erase(binding);
         }
         mDescriptorSet.setSampler(binding, handle, sampler.getSamplerParams());
     }

ios/CocoaPods/Filament.podspec

@@ -1,12 +1,12 @@
 Pod::Spec.new do |spec|
   spec.name = "Filament"
-  spec.version = "1.59.1"
+  spec.version = "1.59.2"
   spec.license = { :type => "Apache 2.0", :file => "LICENSE" }
   spec.homepage = "https://google.github.io/filament"
   spec.authors = "Google LLC."
   spec.summary = "Filament is a real-time physically based rendering engine for Android, iOS, Windows, Linux, macOS, and WASM/WebGL."
   spec.platform = :ios, "11.0"
-  spec.source = { :http => "https://github.com/google/filament/releases/download/v1.59.1/filament-v1.59.1-ios.tgz" }
+  spec.source = { :http => "https://github.com/google/filament/releases/download/v1.59.2/filament-v1.59.2-ios.tgz" }
 
   # Fix linking error with Xcode 12; we do not yet support the simulator on Apple silicon.
   spec.pod_target_xcconfig = {

web/filament-js/package.json

@@ -1,6 +1,6 @@
 {
   "name": "filament",
-  "version": "1.59.1",
+  "version": "1.59.2",
   "description": "Real-time physically based rendering engine",
   "main": "filament.js",
   "module": "filament.js",