Implement transform/clip support for Android WebView.

Transforms are applied above the root-layer.  I fixed LTHCommon to forward
root-layer transforms to sublayers, as the RenderSurface-based logic was previously
clearing transforms and copying over only the scale portion.

The clip rect is treated as the viewport for the purposes of DrawQuads and Renderer
(this is required to avoid awful performance when the WebView is much larger than
the screen).  Because y-flipping the clip rect depends on knowledge of the true
surface size, I also needed to add a new OutputSurface::SurfaceSize() getter and refactored
viewport size throughout the Renderers to separate render-pass draw rect, glViewport rect,
and surface size.

Scale and translate transforms work with this patch, but rotation is still broken.

New tests: LayerTreeHostCommonTest.TransformAboveRootLayer,
GLRendererTest2.ScissorAndViewportWithinNonreshapableSurface,
RendererPixelTest/2* and 3*

NOTRY=true
BUG=230463

Review URL: https://chromiumcodereview.appspot.com/15579002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@204650 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 91 insertions, 20 deletions

diff --git a/cc/output/gl_renderer_unittest.cc b/cc/output/gl_renderer_unittest.cc
index 48a5951..0f901c5 100644
--- a/cc/output/gl_renderer_unittest.cc
+++ b/cc/output/gl_renderer_unittest.cc
@@ -153,8 +153,7 @@ class FakeRendererClient : public RendererClient {
         memory_allocation_limit_bytes_(
             PrioritizedResourceManager::DefaultMemoryAllocationLimit()),
         viewport_size_(gfx::Size(1, 1)),
-        scale_factor_(1.f),
-        is_viewport_changed_(true) {
+        scale_factor_(1.f) {
     root_layer_->CreateRenderSurface();
     RenderPass::Id render_pass_id =
         root_layer_->render_surface()->RenderPassId();
@@ -165,9 +164,9 @@ class FakeRendererClient : public RendererClient {
   }
 
   // RendererClient methods.
-  virtual gfx::Size DeviceViewportSize() const OVERRIDE {
+  virtual gfx::Rect DeviceViewport() const OVERRIDE {
     static gfx::Size fake_size(1, 1);
-    return fake_size;
+    return gfx::Rect(fake_size);
   }
   virtual float DeviceScaleFactor() const OVERRIDE {
     return scale_factor_;
@@ -209,10 +208,7 @@ class FakeRendererClient : public RendererClient {
       gfx::Size viewport_size, float scale_factor) {
     viewport_size_ = viewport_size;
     scale_factor_ = scale_factor;
-    is_viewport_changed_ = true;
   }
-  bool is_viewport_changed() const { return is_viewport_changed_; }
-  void clear_viewport_changed() { is_viewport_changed_ = false; }
 
   RenderPass* root_render_pass() { return render_passes_in_draw_order_.back(); }
   RenderPassList* render_passes_in_draw_order() {
@@ -233,7 +229,6 @@ class FakeRendererClient : public RendererClient {
   size_t memory_allocation_limit_bytes_;
   gfx::Size viewport_size_;
   float scale_factor_;
-  bool is_viewport_changed_;
 };
 
 class FakeRendererGL : public GLRenderer {
@@ -1004,7 +999,7 @@ TEST(GLRendererTest2, ShouldClearRootRenderPass) {
       &mock_client, output_surface.get(), resource_provider.get());
   EXPECT_TRUE(renderer.Initialize());
 
-  gfx::Rect viewport_rect(mock_client.DeviceViewportSize());
+  gfx::Rect viewport_rect(mock_client.DeviceViewport());
   ScopedPtrVector<RenderPass>& render_passes =
       *mock_client.render_passes_in_draw_order();
   render_passes.clear();
@@ -1075,7 +1070,7 @@ TEST(GLRendererTest2, ScissorTestWhenClearing) {
   EXPECT_TRUE(renderer.Initialize());
   EXPECT_FALSE(renderer.Capabilities().using_partial_swap);
 
-  gfx::Rect viewport_rect(mock_client.DeviceViewportSize());
+  gfx::Rect viewport_rect(mock_client.DeviceViewport());
   ScopedPtrVector<RenderPass>& render_passes =
       *mock_client.render_passes_in_draw_order();
   render_passes.clear();
@@ -1105,12 +1100,89 @@ TEST(GLRendererTest2, ScissorTestWhenClearing) {
   renderer.DrawFrame(mock_client.render_passes_in_draw_order());
 }
 
+class NonReshapableOutputSurface : public FakeOutputSurface {
+ public:
+  explicit NonReshapableOutputSurface(
+      scoped_ptr<WebKit::WebGraphicsContext3D> context3d)
+      : FakeOutputSurface(context3d.Pass(), false) {}
+  virtual gfx::Size SurfaceSize() const OVERRIDE { return gfx::Size(500, 500); }
+};
+
+class OffsetViewportRendererClient : public FakeRendererClient {
+ public:
+  virtual gfx::Rect DeviceViewport() const OVERRIDE {
+    return gfx::Rect(10, 10, 100, 100);
+  }
+};
+
+class FlippedScissorAndViewportContext : public TestWebGraphicsContext3D {
+ public:
+  FlippedScissorAndViewportContext()
+      : did_call_viewport_(false), did_call_scissor_(false) {}
+  virtual ~FlippedScissorAndViewportContext() {
+    EXPECT_TRUE(did_call_viewport_);
+    EXPECT_TRUE(did_call_scissor_);
+  }
+
+  virtual void viewport(GLint x, GLint y, GLsizei width, GLsizei height) {
+    EXPECT_EQ(10, x);
+    EXPECT_EQ(390, y);
+    EXPECT_EQ(100, width);
+    EXPECT_EQ(100, height);
+    did_call_viewport_ = true;
+  }
+
+  virtual void scissor(GLint x, GLint y, GLsizei width, GLsizei height) {
+    EXPECT_EQ(30, x);
+    EXPECT_EQ(450, y);
+    EXPECT_EQ(20, width);
+    EXPECT_EQ(20, height);
+    did_call_scissor_ = true;
+  }
+
+ private:
+  bool did_call_viewport_;
+  bool did_call_scissor_;
+};
+
+TEST(GLRendererTest2, ScissorAndViewportWithinNonreshapableSurface) {
+  // In Android WebView, the OutputSurface is unable to respect reshape() calls
+  // and maintains a fixed size. This test verifies that glViewport and
+  // glScissor's Y coordinate is flipped correctly in this environment, and that
+  // the glViewport can be at a nonzero origin within the surface.
+  OffsetViewportRendererClient mock_client;
+  scoped_ptr<OutputSurface> output_surface(make_scoped_ptr(
+      new NonReshapableOutputSurface(scoped_ptr<WebKit::WebGraphicsContext3D>(
+          new FlippedScissorAndViewportContext))));
+  scoped_ptr<ResourceProvider> resource_provider(
+      ResourceProvider::Create(output_surface.get(), 0));
+  FakeRendererGL renderer(
+      &mock_client, output_surface.get(), resource_provider.get());
+  EXPECT_TRUE(renderer.Initialize());
+  EXPECT_FALSE(renderer.Capabilities().using_partial_swap);
+
+  gfx::Rect viewport_rect(mock_client.DeviceViewport().size());
+  gfx::Rect quad_rect = gfx::Rect(20, 20, 20, 20);
+  ScopedPtrVector<RenderPass>& render_passes =
+      *mock_client.render_passes_in_draw_order();
+  render_passes.clear();
+
+  RenderPass::Id root_pass_id(1, 0);
+  TestRenderPass* root_pass = AddRenderPass(
+      &render_passes, root_pass_id, viewport_rect, gfx::Transform());
+  AddClippedQuad(root_pass, quad_rect, SK_ColorGREEN);
+
+  renderer.DecideRenderPassAllocationsForFrame(
+      *mock_client.render_passes_in_draw_order());
+  renderer.DrawFrame(mock_client.render_passes_in_draw_order());
+}
+
 // This test was never actually working as intended. Before adding
 // ShaderCreatorMockGraphicsContext, all shader programs received the same
 // program identifier from the TestWebGraphicsContext3D, so it always passed
 // when checking which shader was used.
 TEST_F(GLRendererShaderTest, DISABLED_DrawRenderPassQuadShaderPermutations) {
-  gfx::Rect viewport_rect(mock_client_.DeviceViewportSize());
+  gfx::Rect viewport_rect(mock_client_.DeviceViewport());
   ScopedPtrVector<RenderPass>* render_passes =
       mock_client_.render_passes_in_draw_order();
 
@@ -1372,7 +1444,7 @@ TEST_F(GLRendererShaderTest, DrawRenderPassQuadSkipsAAForClippingTransform) {
   RenderPass::Id child_pass_id(2, 0);
   TestRenderPass* child_pass;
 
-  gfx::Rect viewport_rect(mock_client_.DeviceViewportSize());
+  gfx::Rect viewport_rect(mock_client_.DeviceViewport());
   RenderPass::Id root_pass_id(1, 0);
   TestRenderPass* root_pass;
 
@@ -1417,7 +1489,7 @@ TEST_F(GLRendererShaderTest, DrawRenderPassQuadSkipsAAForClippingTransform) {
 }
 
 TEST_F(GLRendererShaderTest, DrawSolidColorShader) {
-  gfx::Rect viewport_rect(mock_client_.DeviceViewportSize());
+  gfx::Rect viewport_rect(mock_client_.DeviceViewport());
   ScopedPtrVector<RenderPass>* render_passes =
       mock_client_.render_passes_in_draw_order();
 
@@ -1474,7 +1546,9 @@ class MockOutputSurface : public OutputSurface {
  public:
   MockOutputSurface()
       : OutputSurface(scoped_ptr<WebKit::WebGraphicsContext3D>(
-            new StrictMock<OutputSurfaceMockContext>)) {}
+            new StrictMock<OutputSurfaceMockContext>)) {
+    surface_size_ = gfx::Size(100, 100);
+  }
   virtual ~MockOutputSurface() {}
 
   MOCK_METHOD1(SendFrameToParentCompositor, void(CompositorFrame* frame));
@@ -1497,7 +1571,7 @@ class MockOutputSurfaceTest : public testing::Test, public FakeRendererClient {
   void SwapBuffers() { renderer_.SwapBuffers(ui::LatencyInfo()); }
 
   void DrawFrame() {
-    gfx::Rect viewport_rect(DeviceViewportSize());
+    gfx::Rect viewport_rect(DeviceViewport());
     ScopedPtrVector<RenderPass>* render_passes = render_passes_in_draw_order();
     render_passes->clear();
 
@@ -1508,11 +1582,8 @@ class MockOutputSurfaceTest : public testing::Test, public FakeRendererClient {
 
     EXPECT_CALL(output_surface_, EnsureBackbuffer()).WillRepeatedly(Return());
 
-    if (is_viewport_changed()) {
-      EXPECT_CALL(output_surface_,
-                  Reshape(DeviceViewportSize(), DeviceScaleFactor())).Times(1);
-      clear_viewport_changed();
-    }
+    EXPECT_CALL(output_surface_,
+                Reshape(DeviceViewport().size(), DeviceScaleFactor())).Times(1);
 
     EXPECT_CALL(output_surface_, BindFramebuffer()).Times(1);