Embedder: Refactor EmbedderConfigBuilder by backend (flutter/engine#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: https://github.com/flutter/flutter/issues/137801

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

engine/src/flutter/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",

engine/src/flutter/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
+namespace flutter::testing {
-#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 {
 
 EmbedderConfigBuilder::EmbedderConfigBuilder(
     EmbedderTestContext& context,
@@ -43,49 +27,9 @@ EmbedderConfigBuilder::EmbedderConfigBuilder(
 
   custom_task_runners_.struct_size = sizeof(FlutterCustomTaskRunners);
 
-#ifdef SHELL_ENABLE_GL
+  InitializeGLRendererConfig();
-  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
   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();
+  context_.SetRenderTargetType(type, software_pixfmt);
-
-  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));
 }
 
 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::InitializeGLRendererConfig() {
+  // no-op.
+}
+
+void EmbedderConfigBuilder::SetOpenGLFBOCallBack() {
+  FML_LOG(FATAL) << "OpenGL is not enabled in this build.";
+}
+
+void EmbedderConfigBuilder::SetOpenGLPresentCallBack() {
+  FML_LOG(FATAL) << "OpenGL is not enabled in this build.";
+}
+
+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::InitializeMetalRendererConfig() {
-  if (context_.GetContextType() != EmbedderTestContextType::kMetalContext) {
+  // no-op.
-    return;
 }
 
-  metal_renderer_config_.struct_size = sizeof(metal_renderer_config_);
+void EmbedderConfigBuilder::SetMetalRendererConfig(SkISize surface_size) {
-  EmbedderTestContextMetal& metal_context =
+  FML_LOG(FATAL) << "Metal is not enabled in this build.";
-      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);
-  };
 }
-
+#endif
-#endif  // SHELL_ENABLE_METAL
+#ifndef SHELL_ENABLE_VULKAN
-
+// Vulkan fallback implementations.
-#ifdef SHELL_ENABLE_VULKAN
+// See: flutter/shell/platform/embedder/tests/embedder_config_builder_vulkan.cc.
 
 void EmbedderConfigBuilder::InitializeVulkanRendererConfig() {
-  if (context_.GetContextType() != EmbedderTestContextType::kVulkanContext) {
+  // no-op.
-    return;
 }
 
-  vulkan_renderer_config_.struct_size = sizeof(FlutterVulkanRendererConfig);
+void EmbedderConfigBuilder::SetVulkanRendererConfig(
-  vulkan_renderer_config_.version =
+    SkISize surface_size,
-      static_cast<EmbedderTestContextVulkan&>(context_)
+    std::optional<FlutterVulkanInstanceProcAddressCallback>
-          .vulkan_context_->application_->GetAPIVersion();
+        instance_proc_address_callback) {
-  vulkan_renderer_config_.instance =
+  FML_LOG(FATAL) << "Vulkan is not enabled in this build.";
-      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));
-  };
 }
-
 #endif
 
-}  // namespace testing
+}  // namespace flutter::testing
-}  // namespace flutter

engine/src/flutter/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 flutter::testing {
-namespace testing {
 
 struct UniqueEngineTraits {
   static FlutterEngine InvalidValue() { return nullptr; }
@@ -126,6 +125,10 @@ class EmbedderConfigBuilder {
   void SetupVsyncCallback();
 
  private:
+  void InitializeGLRendererConfig();
+  void InitializeVulkanRendererConfig();
+  void InitializeMetalRendererConfig();
+
   EmbedderTestContext& context_;
   FlutterProjectArgs project_args_ = {};
   FlutterRendererConfig renderer_config_ = {};
@@ -133,13 +136,11 @@ class EmbedderConfigBuilder {
 #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::testing
-}  // namespace flutter
 
 #endif  // FLUTTER_SHELL_PLATFORM_EMBEDDER_TESTS_EMBEDDER_CONFIG_BUILDER_H_

engine/src/flutter/shell/platform/embedder/tests/embedder_config_builder_gl.cc

@@ -0,0 +1,81 @@
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "flutter/shell/platform/embedder/tests/embedder_config_builder.h"
+
+#include "flutter/shell/platform/embedder/tests/embedder_test_compositor_gl.h"
+#include "flutter/shell/platform/embedder/tests/embedder_test_context_gl.h"
+
+namespace flutter::testing {
+
+void EmbedderConfigBuilder::InitializeGLRendererConfig() {
+  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();
+  };
+}
+
+void EmbedderConfigBuilder::SetOpenGLFBOCallBack() {
+  // 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);
+  };
+}
+
+void EmbedderConfigBuilder::SetOpenGLPresentCallBack() {
+  // 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,
+        });
+  };
+}
+
+void EmbedderConfigBuilder::SetOpenGLRendererConfig(SkISize surface_size) {
+  renderer_config_.type = FlutterRendererType::kOpenGL;
+  renderer_config_.open_gl = opengl_renderer_config_;
+  context_.SetupSurface(surface_size);
+}
+
+}  // namespace flutter::testing

engine/src/flutter/shell/platform/embedder/tests/embedder_config_builder_metal.mm

@@ -0,0 +1,47 @@
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "flutter/shell/platform/embedder/tests/embedder_config_builder.h"
+
+#include "flutter/shell/platform/embedder/tests/embedder_test_context_metal.h"
+
+namespace flutter::testing {
+
+void EmbedderConfigBuilder::InitializeMetalRendererConfig() {
+  if (context_.GetContextType() != EmbedderTestContextType::kMetalContext) {
+    return;
+  }
+
+  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::SetMetalRendererConfig(SkISize surface_size) {
+  renderer_config_.type = FlutterRendererType::kMetal;
+  renderer_config_.metal = metal_renderer_config_;
+  context_.SetupSurface(surface_size);
+}
+
+}  // namespace flutter::testing

engine/src/flutter/shell/platform/embedder/tests/embedder_config_builder_vulkan.cc

@@ -0,0 +1,73 @@
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "flutter/shell/platform/embedder/tests/embedder_config_builder.h"
+
+#include "flutter/shell/platform/embedder/tests/embedder_test_context_vulkan.h"
+#include "flutter/vulkan/vulkan_device.h"  // nogncheck
+#include "vulkan/vulkan_core.h"            // nogncheck
+
+namespace flutter::testing {
+
+void EmbedderConfigBuilder::InitializeVulkanRendererConfig() {
+  if (context_.GetContextType() != EmbedderTestContextType::kVulkanContext) {
+    return;
+  }
+
+  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::SetVulkanRendererConfig(
+    SkISize surface_size,
+    std::optional<FlutterVulkanInstanceProcAddressCallback>
+        instance_proc_address_callback) {
+  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);
+}
+
+}  // namespace flutter::testing

engine/src/flutter/shell/platform/embedder/tests/embedder_test_context.cc

@@ -96,6 +96,32 @@ void EmbedderTestContext::SetRootSurfaceTransformation(SkMatrix matrix) {
   root_surface_transformation_ = matrix;
 }
 
+void EmbedderTestContext::SetRenderTargetType(
+    EmbedderTestBackingStoreProducer::RenderTargetType type,
+    FlutterSoftwarePixelFormat software_pixfmt) {
+  // TODO(wrightgeorge): figure out a better way of plumbing through the
+  // GrDirectContext
+  auto& compositor = GetCompositor();
+  auto producer = std::make_unique<EmbedderTestBackingStoreProducer>(
+      compositor.GetGrContext(), type, software_pixfmt);
+#ifdef SHELL_ENABLE_GL
+  switch (type) {
+    case EmbedderTestBackingStoreProducer::RenderTargetType::kOpenGLFramebuffer:
+    case EmbedderTestBackingStoreProducer::RenderTargetType::kOpenGLTexture:
+    case EmbedderTestBackingStoreProducer::RenderTargetType::kOpenGLSurface:
+      producer->SetEGLContext(egl_context_);
+      break;
+    case EmbedderTestBackingStoreProducer::RenderTargetType::kSoftwareBuffer:
+    case EmbedderTestBackingStoreProducer::RenderTargetType::kSoftwareBuffer2:
+    case EmbedderTestBackingStoreProducer::RenderTargetType::kMetalTexture:
+    case EmbedderTestBackingStoreProducer::RenderTargetType::kVulkanImage:
+      // no-op.
+      break;
+  }
+#endif  // SHELL_ENABLE_GL
+  compositor.SetBackingStoreProducer(std::move(producer));
+}
+
 void EmbedderTestContext::AddIsolateCreateCallback(
     const fml::closure& closure) {
   if (closure) {

engine/src/flutter/shell/platform/embedder/tests/embedder_test_context.h

@@ -72,6 +72,10 @@ class EmbedderTestContext {
 
   void SetRootSurfaceTransformation(SkMatrix matrix);
 
+  void SetRenderTargetType(
+      EmbedderTestBackingStoreProducer::RenderTargetType type,
+      FlutterSoftwarePixelFormat software_pixfmt);
+
   void AddIsolateCreateCallback(const fml::closure& closure);
 
   void SetSemanticsUpdateCallback2(SemanticsUpdateCallback2 update_semantics);