cc: Add iterator and big border support to TilingData

cc/tiling_data.h

 // Copyright 2010 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_TILING_DATA_H_
 #define CC_TILING_DATA_H_
 
 #include "base/basictypes.h"
 #include "base/logging.h"
 #include "cc/cc_export.h"
+#include "ui/gfx/rect.h"
 #include "ui/gfx/size.h"
 
 namespace gfx {
-class Rect;
 class Vector2d;
 }
 
 namespace cc {
 
 class CC_EXPORT TilingData {
  public:
-  TilingData(gfx::Size max_texture_size, gfx::Size total_size, bool has_border_texels);
-  ~TilingData();
+  TilingData(
+      gfx::Size max_texture_size,
+      gfx::Size total_size,
+      bool has_border_texels);
+  TilingData(
+      gfx::Size max_texture_size,
+      gfx::Size total_size,
+      int border_texels);

[danakj, 2013/01/15 23:09:05]

can the compiler really tell apart bool/int and know which of these two
contructors to use? it seems at least non-obvious? can we merge them into a
single constructor?

[enne (OOO), 2013/01/15 23:31:40]

Yes it can.  If bool doesn't exist, bool values will use the int overload via
conversion.  If the bool does exist, the bool function will be preferred.

 
   gfx::Size total_size() const { return total_size_; }
   void SetTotalSize(const gfx::Size total_size);
 
   gfx::Size max_texture_size() const { return max_texture_size_; }
   void SetMaxTextureSize(gfx::Size max_texture_size);
 
   int border_texels() const { return border_texels_; }
   void SetHasBorderTexels(bool has_border_texels);
+  void SetBorderTexels(int border_texels);
 
   bool has_empty_bounds() const { return !num_tiles_x_ || !num_tiles_y_; }
   int num_tiles_x() const { return num_tiles_x_; }
   int num_tiles_y() const { return num_tiles_y_; }
+  // Return the tile coordinate whose non-border texels include src_position

[danakj, 2013/01/15 23:09:05]

nit: comments end with period (sorry 80 cols :( )

[enne (OOO), 2013/01/15 23:31:40]

Done.  Exactly 80.  \o/

   int TileXIndexFromSrcCoord(int src_position) const;
   int TileYIndexFromSrcCoord(int src_position) const;
+  // Return the lowest tile coordinate whose border texels include src_position
+  int BorderTileXIndexFromSrcCoord(int src_position) const;
+  int BorderTileYIndexFromSrcCoord(int src_position) const;
 
   gfx::Rect TileBounds(int i, int j) const;
   gfx::Rect TileBoundsWithBorder(int i, int j) const;
   int TilePositionX(int x_index) const;
   int TilePositionY(int y_index) const;
   int TileSizeX(int x_index) const;
   int TileSizeY(int y_index) const;
 
   // Difference between TileBound's and TileBoundWithBorder's origin().
   gfx::Vector2d TextureOffset(int x_index, int y_index) const;
 
+  // Iterate through all indices whose bounds + border intersect with this rect
+  class Iterator {

[danakj, 2013/01/15 23:09:05]

WDYT of IntersectionIterator?

[enne (OOO), 2013/01/15 23:31:40]

Only when somebody adds NonIntersectionIterator and we need to differentiate.  I
think the rect in the ctor makes it obvious what's going on.

+   public:
+    Iterator(const TilingData* tiling_data, gfx::Rect rect);
+    Iterator& operator++();
+    operator bool() const;
+
+    int index_x() const { return index_x_; }
+    int index_y() const { return index_y_; }
+
+   private:
+    void done();
+
+    const TilingData* tiling_data_;
+    gfx::Rect rect_;
+    int index_x_;
+    int index_y_;
+  };
+
  private:
   void AssertTile(int i, int j) const {
     DCHECK_GE(i,  0);
     DCHECK_LT(i, num_tiles_x_);
     DCHECK_GE(j, 0);
     DCHECK_LT(j, num_tiles_y_);
   }
 
   void RecomputeNumTiles();
 
   gfx::Size max_texture_size_;
   gfx::Size total_size_;
-  // This value is always 0 or 1.
   int border_texels_;
 
   // These are computed values.
   int num_tiles_x_;
   int num_tiles_y_;
 };
 
 }  // namespace cc
 
 #endif  // CC_TILING_DATA_H_