Raster display item lists via a visual rect RTree.

third_party/WebKit/Source/platform/graphics/paint/PaintArtifact.h

 // Copyright 2015 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.
 
 #ifndef PaintArtifact_h
 #define PaintArtifact_h
 
 #include "platform/PlatformExport.h"
 #include "platform/graphics/paint/DisplayItemList.h"
 #include "platform/graphics/paint/PaintChunk.h"
@@ skipping 12 matching lines @@
 //
 // It represents a particular state of the world, and should be immutable
 // (const) to most of its users.
 class PLATFORM_EXPORT PaintArtifact final {
     DISALLOW_NEW();
     WTF_MAKE_NONCOPYABLE(PaintArtifact);
 public:
     PaintArtifact();
     ~PaintArtifact();
 
+    typedef WTF::HashMap<DisplayItemClient, IntRect> DisplayItemRectMap;
+
     bool isEmpty() const { return m_displayItemList.isEmpty(); }
 
     DisplayItemList& displayItemList() { return m_displayItemList; }
     const DisplayItemList& displayItemList() const { return m_displayItemList; }
 
     Vector<PaintChunk>& paintChunks() { return m_paintChunks; }
     const Vector<PaintChunk>& paintChunks() const { return m_paintChunks; }
 
     // Resets to an empty paint artifact.
     void reset();
 
     // Returns the approximate memory usage, excluding memory likely to be
     // shared with the embedder after copying to WebDisplayItemList.
     size_t approximateUnsharedMemoryUsage() const;
 
     // Draws the paint artifact to a GraphicsContext.
     void replay(GraphicsContext&) const;
 
     // Writes the paint artifact into a WebDisplayItemList.
-    void appendToWebDisplayItemList(WebDisplayItemList*) const;
+    void appendToWebDisplayItemList(const DisplayItemRectMap& itemRects, WebDisplayItemList*) const;
 
 private:
     DisplayItemList m_displayItemList;
     Vector<PaintChunk> m_paintChunks;
 };
 
 } // namespace blink
 
 #endif // PaintArtifact_h