Windows: Client wrapper: Support querying the graphics adapter chosen by ANGLE (flutter#29294)

Author: jnschulze

shell/platform/windows/client_wrapper/flutter_view_unittests.cc

@@ -16,6 +16,10 @@ namespace {
 // Stub implementation to validate calls to the API.
 class TestWindowsApi : public testing::StubFlutterWindowsApi {
   HWND ViewGetHWND() override { return reinterpret_cast<HWND>(7); }
+
+  IDXGIAdapter* ViewGetGraphicsAdapter() override {
+    return reinterpret_cast<IDXGIAdapter*>(8);
+  }
 };
 
 }  // namespace
@@ -28,4 +32,14 @@ TEST(FlutterViewTest, HwndAccessPassesThrough) {
   EXPECT_EQ(view.GetNativeWindow(), reinterpret_cast<HWND>(7));
 }
 
+TEST(FlutterViewTest, GraphicsAdapterAccessPassesThrough) {
+  testing::ScopedStubFlutterWindowsApi scoped_api_stub(
+      std::make_unique<TestWindowsApi>());
+  auto test_api = static_cast<TestWindowsApi*>(scoped_api_stub.stub());
+  FlutterView view(reinterpret_cast<FlutterDesktopViewRef>(2));
+
+  IDXGIAdapter* adapter = view.GetGraphicsAdapter();
+  EXPECT_EQ(adapter, reinterpret_cast<IDXGIAdapter*>(8));
+}
+
 }  // namespace flutter

shell/platform/windows/client_wrapper/include/flutter/flutter_view.h

@@ -23,6 +23,11 @@ class FlutterView {
   // Returns the backing HWND for the view.
   HWND GetNativeWindow() { return FlutterDesktopViewGetHWND(view_); }
 
+  // Returns the DXGI adapter used for rendering or nullptr in case of error.
+  IDXGIAdapter* GetGraphicsAdapter() {
+    return FlutterDesktopViewGetGraphicsAdapter(view_);
+  }
+
  private:
   // Handle for interacting with the C API's view.
   FlutterDesktopViewRef view_ = nullptr;

shell/platform/windows/client_wrapper/testing/stub_flutter_windows_api.cc

@@ -151,6 +151,13 @@ HWND FlutterDesktopViewGetHWND(FlutterDesktopViewRef controller) {
   return reinterpret_cast<HWND>(-1);
 }
 
+IDXGIAdapter* FlutterDesktopViewGetGraphicsAdapter(FlutterDesktopViewRef view) {
+  if (s_stub_implementation) {
+    return s_stub_implementation->ViewGetGraphicsAdapter();
+  }
+  return nullptr;
+}
+
 FlutterDesktopViewRef FlutterDesktopPluginRegistrarGetView(
     FlutterDesktopPluginRegistrarRef controller) {
   // The stub ignores this, so just return an arbitrary non-zero value.

shell/platform/windows/client_wrapper/testing/stub_flutter_windows_api.h

@@ -72,6 +72,11 @@ class StubFlutterWindowsApi {
   // Called for FlutterDesktopViewGetHWND.
   virtual HWND ViewGetHWND() { return reinterpret_cast<HWND>(1); }
 
+  // Called for FlutterDesktopViewGetGraphicsAdapter.
+  virtual IDXGIAdapter* ViewGetGraphicsAdapter() {
+    return reinterpret_cast<IDXGIAdapter*>(2);
+  }
+
   // Called for FlutterDesktopPluginRegistrarRegisterTopLevelWindowProcDelegate.
   virtual void PluginRegistrarRegisterTopLevelWindowProcDelegate(
       FlutterDesktopWindowProcCallback delegate,

shell/platform/windows/flutter_windows.cc

@@ -188,6 +188,22 @@ HWND FlutterDesktopViewGetHWND(FlutterDesktopViewRef view) {
   return ViewFromHandle(view)->GetPlatformWindow();
 }
 
+IDXGIAdapter* FlutterDesktopViewGetGraphicsAdapter(FlutterDesktopViewRef view) {
+  auto surface_manager = ViewFromHandle(view)->GetEngine()->surface_manager();
+  if (surface_manager) {
+    Microsoft::WRL::ComPtr<ID3D11Device> d3d_device;
+    Microsoft::WRL::ComPtr<IDXGIDevice> dxgi_device;
+    if (surface_manager->GetDevice(d3d_device.GetAddressOf()) &&
+        SUCCEEDED(d3d_device.As(&dxgi_device))) {
+      IDXGIAdapter* adapter;
+      if (SUCCEEDED(dxgi_device->GetAdapter(&adapter))) {
+        return adapter;
+      }
+    }
+  }
+  return nullptr;
+}
+
 FlutterDesktopViewRef FlutterDesktopPluginRegistrarGetView(
     FlutterDesktopPluginRegistrarRef registrar) {
   return HandleForView(registrar->engine->view());

shell/platform/windows/flutter_windows_unittests.cc

@@ -4,6 +4,8 @@
 
 #include "flutter/shell/platform/windows/public/flutter_windows.h"
 
+#include <dxgi.h>
+#include <wrl/client.h>
 #include <thread>
 
 #include "flutter/fml/synchronization/count_down_latch.h"
@@ -253,5 +255,19 @@ TEST_F(WindowsTest, NextFrameCallback) {
   captures.frame_drawn_latch.Wait();
 }
 
+TEST_F(WindowsTest, GetGraphicsAdapter) {
+  auto& context = GetContext();
+  WindowsConfigBuilder builder(context);
+  ViewControllerPtr controller{builder.Run()};
+  ASSERT_NE(controller, nullptr);
+  auto view = FlutterDesktopViewControllerGetView(controller.get());
+
+  Microsoft::WRL::ComPtr<IDXGIAdapter> dxgi_adapter;
+  dxgi_adapter = FlutterDesktopViewGetGraphicsAdapter(view);
+  ASSERT_NE(dxgi_adapter, nullptr);
+  DXGI_ADAPTER_DESC desc{};
+  ASSERT_TRUE(SUCCEEDED(dxgi_adapter->GetDesc(&desc)));
+}
+
 }  // namespace testing
 }  // namespace flutter

shell/platform/windows/public/flutter_windows.h

@@ -5,6 +5,7 @@
 #ifndef FLUTTER_SHELL_PLATFORM_WINDOWS_PUBLIC_FLUTTER_H_
 #define FLUTTER_SHELL_PLATFORM_WINDOWS_PUBLIC_FLUTTER_H_
 
+#include <dxgi.h>
 #include <stddef.h>
 #include <stdint.h>
 #include <windows.h>
@@ -201,6 +202,10 @@ FLUTTER_EXPORT void FlutterDesktopEngineSetNextFrameCallback(
 // Return backing HWND for manipulation in host application.
 FLUTTER_EXPORT HWND FlutterDesktopViewGetHWND(FlutterDesktopViewRef view);
 
+// Returns the DXGI adapter used for rendering or nullptr in case of error.
+FLUTTER_EXPORT IDXGIAdapter* FlutterDesktopViewGetGraphicsAdapter(
+    FlutterDesktopViewRef view);
+
 // ========== Plugin Registrar (extensions) ==========
 // These are Windows-specific extensions to flutter_plugin_registrar.h