Add test to verify coordinate space consistency between custom compos…

…ition and root surface composition.

shell/platform/embedder/BUILD.gn

@@ -87,6 +87,8 @@ test_fixtures("fixtures") {
     "fixtures/compositor.png",
     "fixtures/compositor_with_root_layer_only.png",
     "fixtures/compositor_root_surface_xformation.png",
+    "fixtures/scene_without_custom_compositor.png",
+    "fixtures/scene_without_custom_compositor_with_xform.png",
   ]
 }
 

shell/platform/embedder/fixtures/main.dart

@@ -300,3 +300,35 @@ void can_composite_platform_views_with_platform_layer_on_bottom() {
   signalNativeTest(); // Signal 1
   window.scheduleFrame();
 }
+
+@pragma('vm:entry-point')
+void can_render_scene_without_custom_compositor() {
+  window.onBeginFrame = (Duration duration) {
+    Color red = Color.fromARGB(127, 255, 0, 0);
+    Color green = Color.fromARGB(127, 0, 255, 0);
+    Color blue = Color.fromARGB(127, 0, 0, 255);
+    Color magenta = Color.fromARGB(127, 255, 0, 255);
+    Color gray = Color.fromARGB(127, 127, 127, 127);
+
+    Size size = Size(50.0, 150.0);
+
+    SceneBuilder builder = SceneBuilder();
+
+    builder.pushOffset(0.0, 0.0);
+
+    builder.addPicture(Offset(10.0, 10.0), CreateColoredBox(red, size)); // red - flutter
+
+    builder.addPicture(Offset(20.0, 20.0), CreateColoredBox(green, size)); // green - flutter
+
+    builder.addPicture(Offset(30.0, 30.0), CreateColoredBox(blue, size)); // blue - flutter
+
+    builder.addPicture(Offset(40.0, 40.0), CreateColoredBox(magenta, size)); // magenta - flutter
+
+    builder.addPicture(Offset(50.0, 50.0), CreateColoredBox(gray, size)); // gray - flutter
+
+    builder.pop();
+
+    window.render(builder.build());
+  };
+  window.scheduleFrame();
+}

shell/platform/embedder/tests/embedder_test_context.cc

@@ -60,6 +60,10 @@ const fml::Mapping* EmbedderTestContext::GetIsolateSnapshotInstructions()
   return isolate_snapshot_instructions_.get();
 }
 
+void EmbedderTestContext::SetRootSurfaceTransformation(SkMatrix matrix) {
+  root_surface_transformation_ = matrix;
+}
+
 void EmbedderTestContext::AddIsolateCreateCallback(fml::closure closure) {
   if (closure) {
     isolate_create_callbacks_.push_back(closure);
@@ -177,10 +181,10 @@ void* EmbedderTestContext::GLGetProcAddress(const char* name) {
 }
 
 FlutterTransformation EmbedderTestContext::GetRootSurfaceTransformation() {
-  SkMatrix transformation;
-  if (compositor_) {
-    transformation = compositor_->GetRootSurfaceTransformation();
-  }
+  const auto transformation = compositor_
+                                  ? compositor_->GetRootSurfaceTransformation()
+                                  : root_surface_transformation_;
+
   return FlutterTransformationMake(transformation);
 }
 

shell/platform/embedder/tests/embedder_test_context.h

@@ -42,6 +42,8 @@ class EmbedderTestContext {
 
   const fml::Mapping* GetIsolateSnapshotInstructions() const;
 
+  void SetRootSurfaceTransformation(SkMatrix matrix);
+
   void AddIsolateCreateCallback(fml::closure closure);
 
   void AddNativeCallback(const char* name, Dart_NativeFunction function);
@@ -78,6 +80,7 @@ class EmbedderTestContext {
   std::unique_ptr<TestGLSurface> gl_surface_;
   std::unique_ptr<EmbedderTestCompositor> compositor_;
   NextSceneCallback next_scene_callback_;
+  SkMatrix root_surface_transformation_;
 
   static VoidCallback GetIsolateCreateCallbackHook();
 

shell/platform/embedder/tests/embedder_unittests.cc

@@ -1596,5 +1596,80 @@ TEST_F(EmbedderTest,
                                   scene_image));
 }
 
+TEST_F(EmbedderTest, CanRenderSceneWithoutCustomCompositor) {
+  auto& context = GetEmbedderContext();
+
+  EmbedderConfigBuilder builder(context);
+
+  builder.SetDartEntrypoint("can_render_scene_without_custom_compositor");
+  builder.SetOpenGLRendererConfig();
+  fml::CountDownLatch latch(1);
+
+  sk_sp<SkImage> renderered_scene;
+  context.SetNextSceneCallback([&](auto image) {
+    renderered_scene = std::move(image);
+    latch.CountDown();
+  });
+
+  auto engine = builder.LaunchEngine();
+  ASSERT_TRUE(engine.is_valid());
+
+  // Send a window metrics events so frames may be scheduled.
+  FlutterWindowMetricsEvent event = {};
+  event.struct_size = sizeof(event);
+  event.width = 800;
+  event.height = 600;
+  ASSERT_EQ(FlutterEngineSendWindowMetricsEvent(engine.get(), &event),
+            kSuccess);
+
+  latch.Wait();
+
+  ASSERT_NE(renderered_scene, nullptr);
+
+  ASSERT_TRUE(ImageMatchesFixture("scene_without_custom_compositor.png",
+                                  renderered_scene));
+}
+
+TEST_F(EmbedderTest, CanRenderSceneWithoutCustomCompositorWithTransformation) {
+  auto& context = GetEmbedderContext();
+
+  SkMatrix root_surface_transformation;
+  root_surface_transformation.setRotate(-90.0);
+  root_surface_transformation.setTranslateY(800);
+
+  context.SetRootSurfaceTransformation(root_surface_transformation);
+
+  EmbedderConfigBuilder builder(context);
+
+  builder.SetDartEntrypoint("can_render_scene_without_custom_compositor");
+  builder.SetOpenGLRendererConfig();
+
+  fml::CountDownLatch latch(1);
+
+  sk_sp<SkImage> renderered_scene;
+  context.SetNextSceneCallback([&](auto image) {
+    renderered_scene = std::move(image);
+    latch.CountDown();
+  });
+
+  auto engine = builder.LaunchEngine();
+  ASSERT_TRUE(engine.is_valid());
+
+  // Send a window metrics events so frames may be scheduled.
+  FlutterWindowMetricsEvent event = {};
+  event.struct_size = sizeof(event);
+  event.width = 800;
+  event.height = 600;
+  ASSERT_EQ(FlutterEngineSendWindowMetricsEvent(engine.get(), &event),
+            kSuccess);
+
+  latch.Wait();
+
+  ASSERT_NE(renderered_scene, nullptr);
+
+  ASSERT_TRUE(ImageMatchesFixture(
+      "scene_without_custom_compositor_with_xform.png", renderered_scene));
+}
+
 }  // namespace testing
 }  // namespace flutter