Implement on demand quad rasterization for PicturePiles.

cc/trees/layer_tree_host_unittest.cc

 // Copyright 2011 The Chromium 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 "cc/trees/layer_tree_host.h"
 
 #include "base/synchronization/lock.h"
 #include "cc/animation/timing_function.h"
 #include "cc/layers/content_layer.h"
 #include "cc/layers/content_layer_client.h"
@@ skipping 1029 matching lines @@
     }
 
     virtual void commitCompleteOnThread(LayerTreeHostImpl* impl) OVERRIDE
     {
         ASSERT_EQ(0u, m_layerTreeHost->settings().maxPartialTextureUpdates);
 
         TestWebGraphicsContext3D* context = static_cast<TestWebGraphicsContext3D*>(impl->output_surface()->context3d());
 
         switch (impl->active_tree()->source_frame_number()) {
         case 0:
-            // Number of textures should be one for each layer
-            ASSERT_EQ(2, context->NumTextures());
-            // Number of textures used for commit should be one for each layer.
-            EXPECT_EQ(2, context->NumUsedTextures());
+            // Number of textures should be one for each layer plus an auxiliary
+            // texture for on-demand rasterization.
+            ASSERT_EQ(3, context->NumTextures());
+            // Number of textures used for commit should be one for each layer
+            // plus the auxiliary one on startup.
+            EXPECT_EQ(3, context->NumUsedTextures());
             // Verify that used texture is correct.
             EXPECT_TRUE(context->UsedTexture(context->TextureAt(0)));
             EXPECT_TRUE(context->UsedTexture(context->TextureAt(1)));
 
             context->ResetUsedTextures();
             postSetNeedsCommitToMainThread();
             break;
         case 1:
-            // Number of textures should be doubled as the first textures
-            // are used by impl thread and cannot by used for update.
-            ASSERT_EQ(4, context->NumTextures());
+            // Number of textures should be doubled (excepting the auxiliary)
+            // as the first textures are used by impl thread and cannot by used
+            // for update.
+            ASSERT_EQ(5, context->NumTextures());
             // Number of textures used for commit should still be one for each layer.
             EXPECT_EQ(2, context->NumUsedTextures());
             // First textures should not have been used.
-            EXPECT_FALSE(context->UsedTexture(context->TextureAt(0)));
+            // Index 0 is used by the auxiliary texture.
             EXPECT_FALSE(context->UsedTexture(context->TextureAt(1)));
+            EXPECT_FALSE(context->UsedTexture(context->TextureAt(2)));
             // New textures should have been used.
-            EXPECT_TRUE(context->UsedTexture(context->TextureAt(2)));
             EXPECT_TRUE(context->UsedTexture(context->TextureAt(3)));
+            EXPECT_TRUE(context->UsedTexture(context->TextureAt(4)));
 
             context->ResetUsedTextures();
             postSetNeedsCommitToMainThread();
             break;
         case 2:
             endTest();
             break;
         default:
             NOTREACHED();
             break;
@@ skipping 89 matching lines @@
     }
 
     virtual void commitCompleteOnThread(LayerTreeHostImpl* impl) OVERRIDE
     {
         ASSERT_EQ(1u, m_layerTreeHost->settings().maxPartialTextureUpdates);
 
         TestWebGraphicsContext3D* context = static_cast<TestWebGraphicsContext3D*>(impl->output_surface()->context3d());
 
         switch (impl->active_tree()->source_frame_number()) {
         case 0:
-            // Number of textures should be one for each layer.
-            ASSERT_EQ(4, context->NumTextures());
-            // Number of textures used for commit should be one for each layer.
-            EXPECT_EQ(4, context->NumUsedTextures());
+            // Number of textures should be one for each layer plus an auxiliary
+            // texture for on-demand rasterization.
+            ASSERT_EQ(5, context->NumTextures());
+            // Number of textures used for commit should be one for each layer
+            // plus the auxiliary one on startup.
+            EXPECT_EQ(5, context->NumUsedTextures());
             // Verify that used textures are correct.
             EXPECT_TRUE(context->UsedTexture(context->TextureAt(0)));
             EXPECT_TRUE(context->UsedTexture(context->TextureAt(1)));
             EXPECT_TRUE(context->UsedTexture(context->TextureAt(2)));
             EXPECT_TRUE(context->UsedTexture(context->TextureAt(3)));
 
             context->ResetUsedTextures();
             postSetNeedsCommitToMainThread();
             break;
         case 1:
-            // Number of textures should be two for each content layer and one
+            // Number of textures should be two for each content layer,
+            // an auxiliary one for on-demand rasterization and one
             // for each scrollbar, since they always do a partial update.
-            ASSERT_EQ(6, context->NumTextures());
+            ASSERT_EQ(7, context->NumTextures());
             // Number of textures used for commit should be one for each content
             // layer, and one for the scrollbar layer that paints.
             EXPECT_EQ(3, context->NumUsedTextures());
 
             // First content textures should not have been used.
-            EXPECT_FALSE(context->UsedTexture(context->TextureAt(0)));
+            // Index 0 is used by the auxiliary texture.
             EXPECT_FALSE(context->UsedTexture(context->TextureAt(1)));
+            EXPECT_FALSE(context->UsedTexture(context->TextureAt(2)));
             // The non-painting scrollbar's texture wasn't updated.
-            EXPECT_FALSE(context->UsedTexture(context->TextureAt(2)));
+            EXPECT_FALSE(context->UsedTexture(context->TextureAt(3)));
             // The painting scrollbar's partial update texture was used.
-            EXPECT_TRUE(context->UsedTexture(context->TextureAt(3)));
+            EXPECT_TRUE(context->UsedTexture(context->TextureAt(4)));
             // New textures should have been used.
-            EXPECT_TRUE(context->UsedTexture(context->TextureAt(4)));
             EXPECT_TRUE(context->UsedTexture(context->TextureAt(5)));
+            EXPECT_TRUE(context->UsedTexture(context->TextureAt(6)));
 
             context->ResetUsedTextures();
             postSetNeedsCommitToMainThread();
             break;
         case 2:
-            // Number of textures should be two for each content layer and one
+            // Number of textures should be two for each content layer,
+            // an auxiliary one for on-demand rasterization and one
             // for each scrollbar, since they always do a partial update.
-            ASSERT_EQ(6, context->NumTextures());
+            ASSERT_EQ(7, context->NumTextures());
             // Number of textures used for commit should be one for each content
             // layer, and one for the scrollbar layer that paints.
             EXPECT_EQ(3, context->NumUsedTextures());
 
             // The non-painting scrollbar's texture wasn't updated.
-            EXPECT_FALSE(context->UsedTexture(context->TextureAt(2)));
+            EXPECT_FALSE(context->UsedTexture(context->TextureAt(3)));
             // The painting scrollbar does a partial update.
-            EXPECT_TRUE(context->UsedTexture(context->TextureAt(3)));
+            EXPECT_TRUE(context->UsedTexture(context->TextureAt(4)));
             // One content layer does a partial update also.
-            EXPECT_TRUE(context->UsedTexture(context->TextureAt(4)));
-            EXPECT_FALSE(context->UsedTexture(context->TextureAt(5)));
+            EXPECT_TRUE(context->UsedTexture(context->TextureAt(5)));
+            EXPECT_FALSE(context->UsedTexture(context->TextureAt(6)));
 
             context->ResetUsedTextures();
             postSetNeedsCommitToMainThread();
             break;
         case 3:
             // No textures should be used for commit.
             EXPECT_EQ(0, context->NumUsedTextures());
 
             context->ResetUsedTextures();
             postSetNeedsCommitToMainThread();
@@ skipping 1110 matching lines @@
 private:
     FakeContentLayerClient m_client;
     scoped_refptr<ContentLayer> m_rootLayer;
     int m_numCommits;
 };
 
 SINGLE_AND_MULTI_THREAD_TEST_F(LayerTreeHostTestPinchZoomScrollbarNewRootLayer)
 
 }  // namespace
 }  // namespace cc