cc: Add PictureLayerTiling for impl-side painting

cc/picture_layer_tiling.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_PICTURE_LAYER_TILING_H_
+#define CC_PICTURE_LAYER_TILING_H_
+
+#include "base/basictypes.h"
+#include "base/hash_tables.h"
+#include "base/memory/scoped_ptr.h"
+#include "cc/cc_export.h"
+#include "cc/hash_pair.h"
+#include "cc/region.h"
+#include "cc/tile.h"
+#include "cc/tiling_data.h"
+#include "ui/gfx/rect.h"
+
+namespace cc {
+
+class PictureLayerTiling;
+
+class PictureLayerTilingClient {
+  public:
+   virtual scoped_refptr<Tile> CreateTile(PictureLayerTiling*, gfx::Rect) = 0;
+};
+
+class CC_EXPORT PictureLayerTiling {
+ public:
+  ~PictureLayerTiling();
+
+  static scoped_ptr<PictureLayerTiling> Create(gfx::Size tile_size);
+  scoped_ptr<PictureLayerTiling> Clone() const;
+
+  const PictureLayerTiling& operator=(const PictureLayerTiling&);
+
+  void SetBounds(gfx::Size);
+  gfx::Size bounds() const { return tiling_data_.total_size(); }
+
+  void create_tiles(gfx::Rect);
+  void set_client(PictureLayerTilingClient* client);
+
+  class Iterator {
+   public:
+    Iterator(PictureLayerTiling* tiling, gfx::Rect content_rect);
+    ~Iterator();
+
+    // Visible rect (no borders)
+    gfx::Rect geometry_rect() const;
+    // Full tile rect (not clipped, with borders)
+    gfx::Rect full_tile_rect() const;
+    // Texture rect (in texels) for geometry_rect
+    gfx::Rect texture_rect() const;
+    gfx::Rect opaque_rect() const;
+    gfx::Size texture_size() const;
+
+    Tile* operator->() const { return current_tile_; }
+    Tile* operator*() const { return current_tile_; }
+
+    Iterator& operator++();
+    bool operator==(const Iterator& other) const;
+    bool operator!=(const Iterator& other) const;
+    operator bool() const { return current_tile_; }
+
+   private:
+    PictureLayerTiling* tiling_;
+    Tile* current_tile_;
+    gfx::Rect content_rect_;
+    int tile_i_;
+    int tile_j_;
+    int left_;
+    int top_;
+    int right_;
+    int bottom_;
+
+    friend class PictureLayerTiling;
+  };
+
+  Region OpaqueRegionInContentRect(const gfx::Rect&) const;
+
+  void Reset() { return tiles_.clear(); }
+
+ protected:
+  typedef std::pair<int, int> TileMapKey;
+  typedef base::hash_map<TileMapKey, scoped_refptr<Tile> > TileMap;
+
+  PictureLayerTiling(gfx::Size tileSize);
+  Tile* TileAt(int, int) const;
+
+  PictureLayerTilingClient* client_;
+  TileMap tiles_;
+  TilingData tiling_data_;
+
+  friend class Iterator;
+};
+
+}  // namespace cc
+
+#endif  // CC_PICTURE_LAYER_TILING_H_