CC: Call SwapBuffers instead of PostSubBuffer on full frame update.

This allows us to remove a driver workaround and send less information
in the GLFrameData.

TEST=cc_unittests

Review URL: https://chromiumcodereview.appspot.com/16509008

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@205932 0039d316-1c4b-4281-b951-d872f2087c98

5 files changed, 42 insertions, 23 deletions

diff --git a/cc/output/gl_frame_data.cc b/cc/output/gl_frame_data.cc
index 06cf3f4..aa6cfbc 100644
--- a/cc/output/gl_frame_data.cc
+++ b/cc/output/gl_frame_data.cc
@@ -6,10 +6,7 @@
 
 namespace cc {
 
-GLFrameData::GLFrameData()
-    : sync_point(0),
-      partial_swap_allowed(false) {
-}
+GLFrameData::GLFrameData() : sync_point(0) {}
 
 GLFrameData::~GLFrameData() {}
 
diff --git a/cc/output/gl_frame_data.h b/cc/output/gl_frame_data.h
index b8ec5ec..a8132f9 100644
--- a/cc/output/gl_frame_data.h
+++ b/cc/output/gl_frame_data.h
@@ -24,7 +24,6 @@ class CC_EXPORT GLFrameData {
   uint32 sync_point;
   gfx::Size size;
   gfx::Rect sub_buffer_rect;
-  bool partial_swap_allowed;
 };
 
 }  // namespace cc
diff --git a/cc/output/gl_renderer.cc b/cc/output/gl_renderer.cc
index 6ae5cb2..fb5de4e 100644
--- a/cc/output/gl_renderer.cc
+++ b/cc/output/gl_renderer.cc
@@ -2029,11 +2029,9 @@ void GLRenderer::SwapBuffers() {
                   flipped_y_pos_of_rect_bottom,
                   swap_buffer_rect_.width(),
                   swap_buffer_rect_.height());
-    compositor_frame.gl_frame_data->partial_swap_allowed = true;
   } else {
     compositor_frame.gl_frame_data->sub_buffer_rect =
         gfx::Rect(output_surface_->SurfaceSize());
-    compositor_frame.gl_frame_data->partial_swap_allowed = false;
   }
   output_surface_->SwapBuffers(&compositor_frame);
 
diff --git a/cc/output/output_surface.cc b/cc/output/output_surface.cc
index 0889b96..1a956e4 100644
--- a/cc/output/output_surface.cc
+++ b/cc/output/output_surface.cc
@@ -192,16 +192,17 @@ void OutputSurface::SwapBuffers(cc::CompositorFrame* frame) {
   DCHECK(context3d_);
   DCHECK(frame->gl_frame_data);
 
-  if (frame->gl_frame_data->partial_swap_allowed) {
+  if (frame->gl_frame_data->sub_buffer_rect ==
+      gfx::Rect(frame->gl_frame_data->size)) {
+    // Note that currently this has the same effect as SwapBuffers; we should
+    // consider exposing a different entry point on WebGraphicsContext3D.
+    context3d()->prepareTexture();
+  } else {
     gfx::Rect sub_buffer_rect = frame->gl_frame_data->sub_buffer_rect;
     context3d()->postSubBufferCHROMIUM(sub_buffer_rect.x(),
                                        sub_buffer_rect.y(),
                                        sub_buffer_rect.width(),
                                        sub_buffer_rect.height());
-  } else {
-    // Note that currently this has the same effect as SwapBuffers; we should
-    // consider exposing a different entry point on WebGraphicsContext3D.
-    context3d()->prepareTexture();
   }
 
   if (!has_swap_buffers_complete_callback_)
diff --git a/cc/trees/layer_tree_host_impl_unittest.cc b/cc/trees/layer_tree_host_impl_unittest.cc
index d643656..2439dc5 100644
--- a/cc/trees/layer_tree_host_impl_unittest.cc
+++ b/cc/trees/layer_tree_host_impl_unittest.cc
@@ -2813,11 +2813,19 @@ TEST_F(LayerTreeHostImplTest, ReshapeNotCalledUntilDraw) {
   reshape_tracker->clear_reshape_called();
 }
 
-class PartialSwapTrackerContext : public TestWebGraphicsContext3D {
+class SwapTrackerContext : public TestWebGraphicsContext3D {
  public:
+  SwapTrackerContext() : last_update_type_(NoUpdate) {}
+
+  virtual void prepareTexture() OVERRIDE {
+    update_rect_ = gfx::Rect(width_, height_);
+    last_update_type_ = PrepareTexture;
+  }
+
   virtual void postSubBufferCHROMIUM(int x, int y, int width, int height)
       OVERRIDE {
-    partial_swap_rect_ = gfx::Rect(x, y, width, height);
+    update_rect_ = gfx::Rect(x, y, width, height);
+    last_update_type_ = PostSubBuffer;
   }
 
   virtual WebKit::WebString getString(WebKit::WGC3Denum name) OVERRIDE {
@@ -2829,10 +2837,21 @@ class PartialSwapTrackerContext : public TestWebGraphicsContext3D {
     return WebKit::WebString();
   }
 
-  gfx::Rect partial_swap_rect() const { return partial_swap_rect_; }
+  gfx::Rect update_rect() const { return update_rect_; }
+
+  enum UpdateType {
+    NoUpdate = 0,
+    PrepareTexture,
+    PostSubBuffer
+  };
+
+  UpdateType last_update_type() {
+    return last_update_type_;
+  }
 
  private:
-  gfx::Rect partial_swap_rect_;
+  gfx::Rect update_rect_;
+  UpdateType last_update_type_;
 };
 
 // Make sure damage tracking propagates all the way to the graphics context,
@@ -2840,9 +2859,9 @@ class PartialSwapTrackerContext : public TestWebGraphicsContext3D {
 TEST_F(LayerTreeHostImplTest, PartialSwapReceivesDamageRect) {
   scoped_ptr<OutputSurface> output_surface =
       FakeOutputSurface::Create3d(scoped_ptr<WebKit::WebGraphicsContext3D>(
-          new PartialSwapTrackerContext)).PassAs<OutputSurface>();
-  PartialSwapTrackerContext* partial_swap_tracker =
-      static_cast<PartialSwapTrackerContext*>(output_surface->context3d());
+          new SwapTrackerContext)).PassAs<OutputSurface>();
+  SwapTrackerContext* swap_tracker =
+      static_cast<SwapTrackerContext*>(output_surface->context3d());
 
   // This test creates its own LayerTreeHostImpl, so
   // that we can force partial swap enabled.
@@ -2879,13 +2898,14 @@ TEST_F(LayerTreeHostImplTest, PartialSwapReceivesDamageRect) {
   layer_tree_host_impl->DrawLayers(&frame, base::TimeTicks::Now());
   layer_tree_host_impl->DidDrawAllLayers(frame);
   layer_tree_host_impl->SwapBuffers(frame);
-  gfx::Rect actual_swap_rect = partial_swap_tracker->partial_swap_rect();
+  gfx::Rect actual_swap_rect = swap_tracker->update_rect();
   gfx::Rect expected_swap_rect = gfx::Rect(0, 0, 500, 500);
   EXPECT_EQ(expected_swap_rect.x(), actual_swap_rect.x());
   EXPECT_EQ(expected_swap_rect.y(), actual_swap_rect.y());
   EXPECT_EQ(expected_swap_rect.width(), actual_swap_rect.width());
   EXPECT_EQ(expected_swap_rect.height(), actual_swap_rect.height());
-
+  EXPECT_EQ(swap_tracker->last_update_type(),
+            SwapTrackerContext::PrepareTexture);
   // Second frame, only the damaged area should get swapped. Damage should be
   // the union of old and new child rects.
   // expected damage rect: gfx::Rect(26, 28);
@@ -2896,12 +2916,14 @@ TEST_F(LayerTreeHostImplTest, PartialSwapReceivesDamageRect) {
   layer_tree_host_impl->DrawLayers(&frame, base::TimeTicks::Now());
   host_impl_->DidDrawAllLayers(frame);
   layer_tree_host_impl->SwapBuffers(frame);
-  actual_swap_rect = partial_swap_tracker->partial_swap_rect();
+  actual_swap_rect = swap_tracker->update_rect();
   expected_swap_rect = gfx::Rect(0, 500-28, 26, 28);
   EXPECT_EQ(expected_swap_rect.x(), actual_swap_rect.x());
   EXPECT_EQ(expected_swap_rect.y(), actual_swap_rect.y());
   EXPECT_EQ(expected_swap_rect.width(), actual_swap_rect.width());
   EXPECT_EQ(expected_swap_rect.height(), actual_swap_rect.height());
+  EXPECT_EQ(swap_tracker->last_update_type(),
+            SwapTrackerContext::PostSubBuffer);
 
   // Make sure that partial swap is constrained to the viewport dimensions
   // expected damage rect: gfx::Rect(500, 500);
@@ -2914,12 +2936,14 @@ TEST_F(LayerTreeHostImplTest, PartialSwapReceivesDamageRect) {
   layer_tree_host_impl->DrawLayers(&frame, base::TimeTicks::Now());
   host_impl_->DidDrawAllLayers(frame);
   layer_tree_host_impl->SwapBuffers(frame);
-  actual_swap_rect = partial_swap_tracker->partial_swap_rect();
+  actual_swap_rect = swap_tracker->update_rect();
   expected_swap_rect = gfx::Rect(10, 10);
   EXPECT_EQ(expected_swap_rect.x(), actual_swap_rect.x());
   EXPECT_EQ(expected_swap_rect.y(), actual_swap_rect.y());
   EXPECT_EQ(expected_swap_rect.width(), actual_swap_rect.width());
   EXPECT_EQ(expected_swap_rect.height(), actual_swap_rect.height());
+  EXPECT_EQ(swap_tracker->last_update_type(),
+            SwapTrackerContext::PrepareTexture);
 }
 
 TEST_F(LayerTreeHostImplTest, RootLayerDoesntCreateExtraSurface) {