Add WebGPU stub backend code.

Introduce Enums to support WebGPU.
Start to use header files from dawn.

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

@@ -192,7 +192,8 @@ public enum TargetApi {
         OPENGL      (0x1),
         VULKAN      (0x2),
         METAL       (0x4),
-        ALL         (0x7);
+        WEBGPU      (0x8),
+        ALL         (0x15);
 
         final int number;
 

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

@@ -138,6 +138,10 @@ public enum Backend {
          * Selects the Metal driver if the platform supports it.
          */
         METAL,
+        /**
+         * Select the WebGPU driver if platform supports it.
+         */
+        WEBGPU,
         /**
          * Selects the no-op driver for testing purposes.
          */

filament/backend/CMakeLists.txt

@@ -237,6 +237,15 @@ if (FILAMENT_SUPPORTS_VULKAN)
     endif()
 endif()
 
+if (FILAMENT_SUPPORTS_WEBGPU)
+    list(APPEND SRCS
+            src/webgpu/WebGPUDriver.cpp
+            src/webgpu/WebGPUDriver.h
+            src/webgpu/WebGPUPlatform.cpp
+            src/webgpu/WebGPUPlatform.h
+    )
+endif()
+
 # ==================================================================================================
 # Definitions
 # ==================================================================================================
@@ -339,6 +348,10 @@ if (FILAMENT_SUPPORTS_VULKAN)
     target_link_libraries(${TARGET} PRIVATE SPIRV-Headers)
 endif()
 
+if (FILAMENT_SUPPORTS_WEBGPU)
+    target_link_libraries(${TARGET} PRIVATE webgpu_dawn dawncpp_headers)
+endif()
+
 if (FILAMENT_SUPPORTS_METAL)
     target_link_libraries(${TARGET} PUBLIC "-framework Metal -framework CoreVideo")
 endif()
@@ -426,6 +439,10 @@ install(TARGETS ${TARGET} ${INSTALL_TYPE} DESTINATION lib/${DIST_DIR})
 install(TARGETS vkshaders ${INSTALL_TYPE} DESTINATION lib/${DIST_DIR})
 install(DIRECTORY ${PUBLIC_HDR_DIR}/backend DESTINATION include)
 
+if (FILAMENT_SUPPORTS_WEBGPU)
+    install(TARGETS webgpu_dawn ${INSTALL_TYPE} DESTINATION lib/${DIST_DIR})
+endif()
+
 # ==================================================================================================
 # Test
 # ==================================================================================================

filament/backend/include/backend/DriverEnums.h

@@ -144,7 +144,8 @@ enum class Backend : uint8_t {
     OPENGL = 1,   //!< Selects the OpenGL/ES driver (default on Android)
     VULKAN = 2,   //!< Selects the Vulkan driver if the platform supports it (default on Linux/Windows)
     METAL = 3,    //!< Selects the Metal driver if the platform supports it (default on MacOS/iOS).
-    NOOP = 4,     //!< Selects the no-op driver for testing purposes.
+    WEBGPU = 4,   //!< Selects the Webgpu driver if the platform supports webgpu.
+    NOOP = 5,     //!< Selects the no-op driver for testing purposes.
 };
 
 enum class TimerQueryResult : int8_t {
@@ -163,6 +164,8 @@ static constexpr const char* backendToString(Backend backend) {
             return "Vulkan";
         case Backend::METAL:
             return "Metal";
+        case Backend::WEBGPU:
+            return "WebGPU";
         default:
             return "Unknown";
     }

filament/backend/src/PlatformFactory.cpp

@@ -65,6 +65,9 @@ filament::backend::Platform* createDefaultMetalPlatform();
 #endif
 
 #include "noop/PlatformNoop.h"
+#if defined(FILAMENT_SUPPORTS_WEBGPU)
+    #include "webgpu/WebGPUPlatform.h"
+#endif
 
 namespace filament::backend {
 
@@ -106,6 +109,13 @@ Platform* PlatformFactory::create(Backend* backend) noexcept {
             return nullptr;
         #endif
     }
+    if (*backend == Backend::WEBGPU) {
+        #if defined(FILAMENT_SUPPORTS_WEBGPU)
+            return new WebGPUPlatform();
+        #else
+            return nullptr;
+        #endif
+    }
     if (*backend == Backend::METAL) {
 #if defined(FILAMENT_SUPPORTS_METAL)
         return createDefaultMetalPlatform();