Subtree caching implementation in blink-core

Source/platform/graphics/paint/DisplayItemListTest.cpp

 // Copyright 2014 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 "config.h"
 #include "platform/graphics/paint/DisplayItemList.h"
 
 #include "platform/RuntimeEnabledFeatures.h"
 #include "platform/graphics/GraphicsContext.h"
 #include "platform/graphics/paint/CachedDisplayItem.h"
@@ skipping 445 matching lines @@
     TestDisplayItemClient container1("container1");
     TestDisplayItemClient content1("content1");
     TestDisplayItemClient container2("container2");
     TestDisplayItemClient content2("content2");
     GraphicsContext context(&displayItemList());
     const int backgroundPaintPhase = backgroundDrawingType - DisplayItem::DrawingPaintPhaseFirst;
     const int foregroundPaintPhase = foregroundDrawingType - DisplayItem::DrawingPaintPhaseFirst;
 
     {
         SubtreeRecorder r(context, container1, backgroundPaintPhase);
-        EXPECT_FALSE(r.canUseCache());
         drawRect(context, container1, backgroundDrawingType, FloatRect(100, 100, 100, 100));
         drawRect(context, content1, backgroundDrawingType, FloatRect(100, 100, 50, 200));
     }
     {
         SubtreeRecorder r(context, container1, foregroundPaintPhase);
-        EXPECT_FALSE(r.canUseCache());
         drawRect(context, content1, foregroundDrawingType, FloatRect(100, 100, 50, 200));
         drawRect(context, container1, foregroundDrawingType, FloatRect(100, 100, 100, 100));
     }
     {
         SubtreeRecorder r(context, container2, backgroundPaintPhase);
-        EXPECT_FALSE(r.canUseCache());
         drawRect(context, container2, backgroundDrawingType, FloatRect(100, 200, 100, 100));
         drawRect(context, content2, backgroundDrawingType, FloatRect(100, 200, 50, 200));
     }
     {
         SubtreeRecorder r(context, container2, foregroundPaintPhase);
-        EXPECT_FALSE(r.canUseCache());
         drawRect(context, content2, foregroundDrawingType, FloatRect(100, 200, 50, 200));
         drawRect(context, container2, foregroundDrawingType, FloatRect(100, 200, 100, 100));
     }
     displayItemList().commitNewDisplayItems();
 
     EXPECT_DISPLAY_LIST(displayItemList().displayItems(), 16,
         TestDisplayItem(container1, DisplayItem::paintPhaseToBeginSubtreeType(backgroundPaintPhase)),
         TestDisplayItem(container1, backgroundDrawingType),
         TestDisplayItem(content1, backgroundDrawingType),
         TestDisplayItem(container1, DisplayItem::paintPhaseToEndSubtreeType(backgroundPaintPhase)),
 
         TestDisplayItem(container1, DisplayItem::paintPhaseToBeginSubtreeType(foregroundPaintPhase)),
         TestDisplayItem(content1, foregroundDrawingType),
         TestDisplayItem(container1, foregroundDrawingType),
         TestDisplayItem(container1, DisplayItem::paintPhaseToEndSubtreeType(foregroundPaintPhase)),
 
         TestDisplayItem(container2, DisplayItem::paintPhaseToBeginSubtreeType(backgroundPaintPhase)),
         TestDisplayItem(container2, backgroundDrawingType),
         TestDisplayItem(content2, backgroundDrawingType),
         TestDisplayItem(container2, DisplayItem::paintPhaseToEndSubtreeType(backgroundPaintPhase)),
 
         TestDisplayItem(container2, DisplayItem::paintPhaseToBeginSubtreeType(foregroundPaintPhase)),
         TestDisplayItem(content2, foregroundDrawingType),
         TestDisplayItem(container2, foregroundDrawingType),
         TestDisplayItem(container2, DisplayItem::paintPhaseToEndSubtreeType(foregroundPaintPhase)));
 
     // Simulate the situation when container1 e.g. gets a z-index that is now greater than container2.
-    displayItemList().createAndAppend<CachedDisplayItem>(container2, DisplayItem::paintPhaseToCachedSubtreeType(backgroundPaintPhase));
+    EXPECT_TRUE(SubtreeRecorder::useCachedSubtreeIfPossible(context, container2, backgroundPaintPhase));
     EXPECT_EQ((size_t)1, newPaintListBeforeUpdate().size());
     EXPECT_TRUE(newPaintListBeforeUpdate().last().isCachedSubtree());
-    displayItemList().createAndAppend<CachedDisplayItem>(container2, DisplayItem::paintPhaseToCachedSubtreeType(foregroundPaintPhase));
+    EXPECT_TRUE(SubtreeRecorder::useCachedSubtreeIfPossible(context, container2, foregroundPaintPhase));
     EXPECT_EQ((size_t)2, newPaintListBeforeUpdate().size());
     EXPECT_TRUE(newPaintListBeforeUpdate().last().isCachedSubtree());
 
-    displayItemList().createAndAppend<CachedDisplayItem>(container1, DisplayItem::paintPhaseToCachedSubtreeType(backgroundPaintPhase));
+    EXPECT_TRUE(SubtreeRecorder::useCachedSubtreeIfPossible(context, container1, backgroundPaintPhase));
     EXPECT_EQ((size_t)3, newPaintListBeforeUpdate().size());
     EXPECT_TRUE(newPaintListBeforeUpdate().last().isCachedSubtree());
-    displayItemList().createAndAppend<CachedDisplayItem>(container1, DisplayItem::paintPhaseToCachedSubtreeType(foregroundPaintPhase));
+    EXPECT_TRUE(SubtreeRecorder::useCachedSubtreeIfPossible(context, container1, foregroundPaintPhase));
     EXPECT_EQ((size_t)4, newPaintListBeforeUpdate().size());
     EXPECT_TRUE(newPaintListBeforeUpdate().last().isCachedSubtree());
     displayItemList().commitNewDisplayItems();
 
     EXPECT_DISPLAY_LIST(displayItemList().displayItems(), 16,
         TestDisplayItem(container2, DisplayItem::paintPhaseToBeginSubtreeType(backgroundDrawingType)),
         TestDisplayItem(container2, backgroundDrawingType),
         TestDisplayItem(content2, backgroundDrawingType),
         TestDisplayItem(container2, DisplayItem::paintPhaseToEndSubtreeType(backgroundDrawingType)),
 
@@ skipping 145 matching lines @@
     drawRect(context, third, backgroundDrawingType, FloatRect(0, 0, 100, 100));
     displayItemList().commitNewDisplayItems();
 
     // Empty clips should have been optimized out.
     EXPECT_DISPLAY_LIST(displayItemList().displayItems(), 2,
         TestDisplayItem(first, backgroundDrawingType),
         TestDisplayItem(third, backgroundDrawingType));
 }
 
 } // namespace blink