Embedder: Refactor EmbedderConfigBuilder by backend (#56598)

Extracts backend-specific code in EmbedderConfigBuilder to separate translation units. In particular, this allows for less conditional header includes, and more specifically, for code relating to the Metal backend to include headers that include Objective-C types -- today we cast these all to void* to avoid declaring them in headers, which requires special handling for ARC.

An alternative approach would have been to extract backend-specific subclasses, but there are test suites such as EmbedderTestMultiBackend that are executed against multiple backends, which currently make that approach impractical, though that should likely be the long-term goal.

Issue: flutter/flutter#137801

[C++, Objective-C, Java style guides]: https://github.com/flutter/engine/blob/main/CONTRIBUTING.md#style

Author: cbracken

shell/platform/embedder/BUILD.gn

@@ -313,6 +313,7 @@ if (enable_unittests) {
 
     if (test_enable_gl) {
       sources += [
+        "tests/embedder_config_builder_gl.cc",
         "tests/embedder_test_compositor_gl.cc",
         "tests/embedder_test_compositor_gl.h",
         "tests/embedder_test_context_gl.cc",
@@ -328,6 +329,7 @@ if (enable_unittests) {
 
     if (test_enable_metal) {
       sources += [
+        "tests/embedder_config_builder_metal.mm",
         "tests/embedder_test_compositor_metal.h",
         "tests/embedder_test_compositor_metal.mm",
         "tests/embedder_test_context_metal.h",
@@ -340,6 +342,7 @@ if (enable_unittests) {
 
     if (test_enable_vulkan) {
       sources += [
+        "tests/embedder_config_builder_vulkan.cc",
         "tests/embedder_test_compositor_vulkan.cc",
         "tests/embedder_test_compositor_vulkan.h",
         "tests/embedder_test_context_vulkan.cc",

shell/platform/embedder/tests/embedder_config_builder.cc

@@ -11,23 +11,7 @@
 #include "third_party/skia/include/core/SkBitmap.h"
 #include "third_party/skia/include/core/SkImage.h"
 
-#ifdef SHELL_ENABLE_GL
-#include "flutter/shell/platform/embedder/tests/embedder_test_compositor_gl.h"
-#include "flutter/shell/platform/embedder/tests/embedder_test_context_gl.h"
-#endif
-
-#ifdef SHELL_ENABLE_VULKAN
-#include "flutter/shell/platform/embedder/tests/embedder_test_context_vulkan.h"
-#include "flutter/vulkan/vulkan_device.h"  // nogncheck
-#include "vulkan/vulkan_core.h"            // nogncheck
-#endif
-
-#ifdef SHELL_ENABLE_METAL
-#include "flutter/shell/platform/embedder/tests/embedder_test_context_metal.h"
-#endif
-
-namespace flutter {
-namespace testing {
+namespace flutter::testing {
 
 EmbedderConfigBuilder::EmbedderConfigBuilder(
     EmbedderTestContext& context,
@@ -43,49 +27,9 @@ EmbedderConfigBuilder::EmbedderConfigBuilder(
 
   custom_task_runners_.struct_size = sizeof(FlutterCustomTaskRunners);
 
-#ifdef SHELL_ENABLE_GL
-  opengl_renderer_config_.struct_size = sizeof(FlutterOpenGLRendererConfig);
-  opengl_renderer_config_.make_current = [](void* context) -> bool {
-    return reinterpret_cast<EmbedderTestContextGL*>(context)->GLMakeCurrent();
-  };
-  opengl_renderer_config_.clear_current = [](void* context) -> bool {
-    return reinterpret_cast<EmbedderTestContextGL*>(context)->GLClearCurrent();
-  };
-  opengl_renderer_config_.present_with_info =
-      [](void* context, const FlutterPresentInfo* present_info) -> bool {
-    return reinterpret_cast<EmbedderTestContextGL*>(context)->GLPresent(
-        *present_info);
-  };
-  opengl_renderer_config_.fbo_with_frame_info_callback =
-      [](void* context, const FlutterFrameInfo* frame_info) -> uint32_t {
-    return reinterpret_cast<EmbedderTestContextGL*>(context)->GLGetFramebuffer(
-        *frame_info);
-  };
-  opengl_renderer_config_.populate_existing_damage = nullptr;
-  opengl_renderer_config_.make_resource_current = [](void* context) -> bool {
-    return reinterpret_cast<EmbedderTestContextGL*>(context)
-        ->GLMakeResourceCurrent();
-  };
-  opengl_renderer_config_.gl_proc_resolver = [](void* context,
-                                                const char* name) -> void* {
-    return reinterpret_cast<EmbedderTestContextGL*>(context)->GLGetProcAddress(
-        name);
-  };
-  opengl_renderer_config_.fbo_reset_after_present = true;
-  opengl_renderer_config_.surface_transformation =
-      [](void* context) -> FlutterTransformation {
-    return reinterpret_cast<EmbedderTestContext*>(context)
-        ->GetRootSurfaceTransformation();
-  };
-#endif
-
-#ifdef SHELL_ENABLE_METAL
+  InitializeGLRendererConfig();
   InitializeMetalRendererConfig();
-#endif
-
-#ifdef SHELL_ENABLE_VULKAN
   InitializeVulkanRendererConfig();
-#endif
 
   software_renderer_config_.struct_size = sizeof(FlutterSoftwareRendererConfig);
   software_renderer_config_.surface_present_callback =
@@ -141,37 +85,6 @@ void EmbedderConfigBuilder::SetSoftwareRendererConfig(SkISize surface_size) {
   context_.SetupSurface(surface_size);
 }
 
-void EmbedderConfigBuilder::SetOpenGLFBOCallBack() {
-#ifdef SHELL_ENABLE_GL
-  // SetOpenGLRendererConfig must be called before this.
-  FML_CHECK(renderer_config_.type == FlutterRendererType::kOpenGL);
-  renderer_config_.open_gl.fbo_callback = [](void* context) -> uint32_t {
-    FlutterFrameInfo frame_info = {};
-    // fbo_callback doesn't use the frame size information, only
-    // fbo_callback_with_frame_info does.
-    frame_info.struct_size = sizeof(FlutterFrameInfo);
-    frame_info.size.width = 0;
-    frame_info.size.height = 0;
-    return reinterpret_cast<EmbedderTestContextGL*>(context)->GLGetFramebuffer(
-        frame_info);
-  };
-#endif
-}
-
-void EmbedderConfigBuilder::SetOpenGLPresentCallBack() {
-#ifdef SHELL_ENABLE_GL
-  // SetOpenGLRendererConfig must be called before this.
-  FML_CHECK(renderer_config_.type == FlutterRendererType::kOpenGL);
-  renderer_config_.open_gl.present = [](void* context) -> bool {
-    // passing a placeholder fbo_id.
-    return reinterpret_cast<EmbedderTestContextGL*>(context)->GLPresent(
-        FlutterPresentInfo{
-            .fbo_id = 0,
-        });
-  };
-#endif
-}
-
 void EmbedderConfigBuilder::SetRendererConfig(EmbedderTestContextType type,
                                               SkISize surface_size) {
   switch (type) {
@@ -190,38 +103,6 @@ void EmbedderConfigBuilder::SetRendererConfig(EmbedderTestContextType type,
   }
 }
 
-void EmbedderConfigBuilder::SetOpenGLRendererConfig(SkISize surface_size) {
-#ifdef SHELL_ENABLE_GL
-  renderer_config_.type = FlutterRendererType::kOpenGL;
-  renderer_config_.open_gl = opengl_renderer_config_;
-  context_.SetupSurface(surface_size);
-#endif
-}
-
-void EmbedderConfigBuilder::SetMetalRendererConfig(SkISize surface_size) {
-#ifdef SHELL_ENABLE_METAL
-  renderer_config_.type = FlutterRendererType::kMetal;
-  renderer_config_.metal = metal_renderer_config_;
-  context_.SetupSurface(surface_size);
-#endif
-}
-
-void EmbedderConfigBuilder::SetVulkanRendererConfig(
-    SkISize surface_size,
-    std::optional<FlutterVulkanInstanceProcAddressCallback>
-        instance_proc_address_callback) {
-#ifdef SHELL_ENABLE_VULKAN
-  renderer_config_.type = FlutterRendererType::kVulkan;
-  FlutterVulkanRendererConfig vulkan_renderer_config = vulkan_renderer_config_;
-  if (instance_proc_address_callback.has_value()) {
-    vulkan_renderer_config.get_instance_proc_address_callback =
-        instance_proc_address_callback.value();
-  }
-  renderer_config_.vulkan = vulkan_renderer_config;
-  context_.SetupSurface(surface_size);
-#endif
-}
-
 void EmbedderConfigBuilder::SetAssetsPath() {
   project_args_.assets_path = context_.GetAssetsPath().c_str();
 }
@@ -406,18 +287,7 @@ FlutterCompositor& EmbedderConfigBuilder::GetCompositor() {
 void EmbedderConfigBuilder::SetRenderTargetType(
     EmbedderTestBackingStoreProducer::RenderTargetType type,
     FlutterSoftwarePixelFormat software_pixfmt) {
-  auto& compositor = context_.GetCompositor();
-
-  auto producer = std::make_unique<EmbedderTestBackingStoreProducer>(
-      compositor.GetGrContext(), type, software_pixfmt);
-
-#ifdef SHELL_ENABLE_GL
-  producer->SetEGLContext(context_.egl_context_);
-#endif
-
-  // TODO(wrightgeorge): figure out a better way of plumbing through the
-  // GrDirectContext
-  compositor.SetBackingStoreProducer(std::move(producer));
+  context_.SetRenderTargetType(type, software_pixfmt);
 }
 
 UniqueEngine EmbedderConfigBuilder::LaunchEngine() const {
@@ -479,93 +349,52 @@ UniqueEngine EmbedderConfigBuilder::SetupEngine(bool run) const {
   return UniqueEngine{engine};
 }
 
-#ifdef SHELL_ENABLE_METAL
+#ifndef SHELL_ENABLE_GL
+// OpenGL fallback implementations.
+// See: flutter/shell/platform/embedder/tests/embedder_config_builder_gl.cc.
 
-void EmbedderConfigBuilder::InitializeMetalRendererConfig() {
-  if (context_.GetContextType() != EmbedderTestContextType::kMetalContext) {
-    return;
-  }
+void EmbedderConfigBuilder::InitializeGLRendererConfig() {
+  // no-op.
+}
 
-  metal_renderer_config_.struct_size = sizeof(metal_renderer_config_);
-  EmbedderTestContextMetal& metal_context =
-      reinterpret_cast<EmbedderTestContextMetal&>(context_);
-
-  metal_renderer_config_.device =
-      metal_context.GetTestMetalContext()->GetMetalDevice();
-  metal_renderer_config_.present_command_queue =
-      metal_context.GetTestMetalContext()->GetMetalCommandQueue();
-  metal_renderer_config_.get_next_drawable_callback =
-      [](void* user_data, const FlutterFrameInfo* frame_info) {
-        return reinterpret_cast<EmbedderTestContextMetal*>(user_data)
-            ->GetNextDrawable(frame_info);
-      };
-  metal_renderer_config_.present_drawable_callback =
-      [](void* user_data, const FlutterMetalTexture* texture) -> bool {
-    EmbedderTestContextMetal* metal_context =
-        reinterpret_cast<EmbedderTestContextMetal*>(user_data);
-    return metal_context->Present(texture->texture_id);
-  };
-  metal_renderer_config_.external_texture_frame_callback =
-      [](void* user_data, int64_t texture_id, size_t width, size_t height,
-         FlutterMetalExternalTexture* texture_out) -> bool {
-    EmbedderTestContextMetal* metal_context =
-        reinterpret_cast<EmbedderTestContextMetal*>(user_data);
-    return metal_context->PopulateExternalTexture(texture_id, width, height,
-                                                  texture_out);
-  };
+void EmbedderConfigBuilder::SetOpenGLFBOCallBack() {
+  FML_LOG(FATAL) << "OpenGL is not enabled in this build.";
 }
 
-#endif  // SHELL_ENABLE_METAL
+void EmbedderConfigBuilder::SetOpenGLPresentCallBack() {
+  FML_LOG(FATAL) << "OpenGL is not enabled in this build.";
+}
 
-#ifdef SHELL_ENABLE_VULKAN
+void EmbedderConfigBuilder::SetOpenGLRendererConfig(SkISize surface_size) {
+  FML_LOG(FATAL) << "OpenGL is not enabled in this build.";
+}
+#endif
+#ifndef SHELL_ENABLE_METAL
+// Metal fallback implementations.
+// See: flutter/shell/platform/embedder/tests/embedder_config_builder_metal.mm.
 
-void EmbedderConfigBuilder::InitializeVulkanRendererConfig() {
-  if (context_.GetContextType() != EmbedderTestContextType::kVulkanContext) {
-    return;
-  }
+void EmbedderConfigBuilder::InitializeMetalRendererConfig() {
+  // no-op.
+}
 
-  vulkan_renderer_config_.struct_size = sizeof(FlutterVulkanRendererConfig);
-  vulkan_renderer_config_.version =
-      static_cast<EmbedderTestContextVulkan&>(context_)
-          .vulkan_context_->application_->GetAPIVersion();
-  vulkan_renderer_config_.instance =
-      static_cast<EmbedderTestContextVulkan&>(context_)
-          .vulkan_context_->application_->GetInstance();
-  vulkan_renderer_config_.physical_device =
-      static_cast<EmbedderTestContextVulkan&>(context_)
-          .vulkan_context_->device_->GetPhysicalDeviceHandle();
-  vulkan_renderer_config_.device =
-      static_cast<EmbedderTestContextVulkan&>(context_)
-          .vulkan_context_->device_->GetHandle();
-  vulkan_renderer_config_.queue_family_index =
-      static_cast<EmbedderTestContextVulkan&>(context_)
-          .vulkan_context_->device_->GetGraphicsQueueIndex();
-  vulkan_renderer_config_.queue =
-      static_cast<EmbedderTestContextVulkan&>(context_)
-          .vulkan_context_->device_->GetQueueHandle();
-  vulkan_renderer_config_.get_instance_proc_address_callback =
-      EmbedderTestContextVulkan::InstanceProcAddr;
-  vulkan_renderer_config_.get_next_image_callback =
-      [](void* context,
-         const FlutterFrameInfo* frame_info) -> FlutterVulkanImage {
-    VkImage image =
-        reinterpret_cast<EmbedderTestContextVulkan*>(context)->GetNextImage(
-            {static_cast<int>(frame_info->size.width),
-             static_cast<int>(frame_info->size.height)});
-    return {
-        .struct_size = sizeof(FlutterVulkanImage),
-        .image = reinterpret_cast<uint64_t>(image),
-        .format = VK_FORMAT_R8G8B8A8_UNORM,
-    };
-  };
-  vulkan_renderer_config_.present_image_callback =
-      [](void* context, const FlutterVulkanImage* image) -> bool {
-    return reinterpret_cast<EmbedderTestContextVulkan*>(context)->PresentImage(
-        reinterpret_cast<VkImage>(image->image));
-  };
+void EmbedderConfigBuilder::SetMetalRendererConfig(SkISize surface_size) {
+  FML_LOG(FATAL) << "Metal is not enabled in this build.";
+}
+#endif
+#ifndef SHELL_ENABLE_VULKAN
+// Vulkan fallback implementations.
+// See: flutter/shell/platform/embedder/tests/embedder_config_builder_vulkan.cc.
+
+void EmbedderConfigBuilder::InitializeVulkanRendererConfig() {
+  // no-op.
 }
 
+void EmbedderConfigBuilder::SetVulkanRendererConfig(
+    SkISize surface_size,
+    std::optional<FlutterVulkanInstanceProcAddressCallback>
+        instance_proc_address_callback) {
+  FML_LOG(FATAL) << "Vulkan is not enabled in this build.";
+}
 #endif
 
-}  // namespace testing
-}  // namespace flutter
+}  // namespace flutter::testing

shell/platform/embedder/tests/embedder_config_builder.h

@@ -11,8 +11,7 @@
 #include "flutter/shell/platform/embedder/tests/embedder_test.h"
 #include "flutter/shell/platform/embedder/tests/embedder_test_context_software.h"
 
-namespace flutter {
-namespace testing {
+namespace flutter::testing {
 
 struct UniqueEngineTraits {
   static FlutterEngine InvalidValue() { return nullptr; }
@@ -126,20 +125,22 @@ class EmbedderConfigBuilder {
   void SetupVsyncCallback();
 
  private:
+  void InitializeGLRendererConfig();
+  void InitializeVulkanRendererConfig();
+  void InitializeMetalRendererConfig();
+
   EmbedderTestContext& context_;
   FlutterProjectArgs project_args_ = {};
   FlutterRendererConfig renderer_config_ = {};
   FlutterSoftwareRendererConfig software_renderer_config_ = {};
 #ifdef SHELL_ENABLE_GL
   FlutterOpenGLRendererConfig opengl_renderer_config_ = {};
 #endif
-#ifdef SHELL_ENABLE_VULKAN
-  void InitializeVulkanRendererConfig();
-  FlutterVulkanRendererConfig vulkan_renderer_config_ = {};
-#endif
 #ifdef SHELL_ENABLE_METAL
-  void InitializeMetalRendererConfig();
   FlutterMetalRendererConfig metal_renderer_config_ = {};
+#endif
+#ifdef SHELL_ENABLE_VULKAN
+  FlutterVulkanRendererConfig vulkan_renderer_config_ = {};
 #endif
   std::string dart_entrypoint_;
   FlutterCustomTaskRunners custom_task_runners_ = {};
@@ -153,7 +154,6 @@ class EmbedderConfigBuilder {
   FML_DISALLOW_COPY_AND_ASSIGN(EmbedderConfigBuilder);
 };
 
-}  // namespace testing
-}  // namespace flutter
+}  // namespace flutter::testing
 
 #endif  // FLUTTER_SHELL_PLATFORM_EMBEDDER_TESTS_EMBEDDER_CONFIG_BUILDER_H_