Introduce Tile Versions

cc/tile.h

 // Copyright 2012 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 CC_TILE_H_
 #define CC_TILE_H_
 
 #include "base/memory/ref_counted.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/memory/scoped_vector.h"
 #include "cc/picture_pile.h"
 #include "cc/resource_provider.h"
 #include "cc/tile_priority.h"
 #include "ui/gfx/rect.h"
 #include "ui/gfx/size.h"
 
 namespace cc {
 
+class Tile;
 class TileManager;
 
 enum TileQuality {
   LOW_TILE_QUALITY,
   NORMAL_TILE_QUALITY
 };
 
+class TileVersion {
+public:
+  TileVersion(Tile* tile, int frame_number,
+              PicturePile* picture_pile)
+    : tile_(tile),
+      frame_number_(frame_number),
+      picture_pile_(picture_pile),
+      resource_id_(0) {}
+
+  int frame_number() const { return frame_number_; }
+
+  const PicturePile* picture_pile() const {
+    return picture_pile_;
+  }
+
+  const TilePriority& priority() const {
+    return priority_;
+  }
+
+  void ModifyPriority(const TilePriority& priority) {
+    priority_ = priority;
+  }
+
+  ResourceProvider::ResourceId resource_id() const {
+    return resource_id_;
+  }
+
+private:
+  Tile* tile_;
+  int frame_number_;
+  PicturePile* picture_pile_;
+  TilePriority priority_;
+  ResourceProvider::ResourceId resource_id_;
+};
+
 class Tile : public base::RefCounted<Tile> {
  public:
   Tile(TileManager* tile_manager,
        gfx::Size tile_size,
+       GLenum format,
        gfx::Rect rect_inside_picture,
        TileQuality quality);
 
-  void SetPicturePile(int frame_number, scoped_ptr<PicturePile> picture_pile) {}
-  void SetPriority(int frame_number, TilePriority) {}
+  void SetPicturePile(int frame_number, PicturePile* picture_pile);
+  void ModifyPriority(int frame_number, const TilePriority& priority);
 
-  bool IsDrawable(int frame_number) { return false; }
-  ResourceProvider::ResourceId GetDrawableResourceId(int frame_number) { return 0; }
+  // Returns 0 if not drawable.
+  ResourceProvider::ResourceId GetDrawableResourceId(int frame_number);
+
+ protected:
+  // Methods called by TileManager.
+  void DeleteVersionOnRequestOfTileManager(int frame_number);
 
  private:
   friend class base::RefCounted<Tile>;
   friend class TileManager;
 
+  TileVersion* GetVersion(int frame_number);
   ~Tile();
 
   TileManager* tile_manager_;
   gfx::Rect tile_size_;
+  GLenum format_;
   gfx::Rect rect_inside_picture_;
   TileQuality quality_;
+  ScopedVector<TileVersion> versions_;
 };
 
+
 }  // namespace cc
 #endif