cc: Add tiling raster tile iterators.

cc/base/tiling_data.cc

 // 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.
 
 #include "cc/base/tiling_data.h"
 
 #include <algorithm>
 
+#include "cc/base/util.h"
 #include "ui/gfx/rect.h"
 #include "ui/gfx/vector2d.h"
 
 namespace cc {
 
 static int ComputeNumTiles(int max_texture_size,
                            int total_size,
                            int border_texels) {
   if (max_texture_size - 2 * border_texels <= 0)
     return total_size > 0 && max_texture_size >= total_size ? 1 : 0;
@@ skipping 46 matching lines @@
 
 void TilingData::SetBorderTexels(int border_texels) {
   border_texels_ = border_texels;
   RecomputeNumTiles();
 }
 
 std::pair<int, int> TilingData::UnclampedFirstBorderTileIndexFromSrcCoord(
     int x,
     int y) const {
   int inner_tile_width = max_texture_size_.width() - 2 * border_texels_;
-  int result_x = (x - 2 * border_texels_) / inner_tile_width;
+  int result_x =
+      RoundDown(x - 2 * border_texels_, inner_tile_width) / inner_tile_width;

[enne (OOO), 2014/03/06 02:30:45]

Why?

[vmpstr, 2014/03/07 18:22:23]

I moved this to a separate patch. It's a bug in the spiral iterator.

 
   int inner_tile_height = max_texture_size_.height() - 2 * border_texels_;
-  int result_y = (y - 2 * border_texels_) / inner_tile_height;
+  int result_y =
+      RoundDown(y - 2 * border_texels_, inner_tile_height) / inner_tile_height;
 
   return std::make_pair(result_x, result_y);
 }
 
 std::pair<int, int> TilingData::UnclampedLastBorderTileIndexFromSrcCoord(
     int x,
     int y) const {
   int inner_tile_width = max_texture_size_.width() - 2 * border_texels_;
-  int result_x = x / inner_tile_width;
+  int result_x = RoundDown(x, inner_tile_width) / inner_tile_width;
 
   int inner_tile_height = max_texture_size_.height() - 2 * border_texels_;
-  int result_y = y / inner_tile_height;
+  int result_y = RoundDown(y, inner_tile_height) / inner_tile_height;
 
   return std::make_pair(result_x, result_y);
 }
 
 int TilingData::TileXIndexFromSrcCoord(int src_position) const {
   if (num_tiles_x_ <= 1)
     return 0;
 
   DCHECK_GT(max_texture_size_.width() - 2 * border_texels_, 0);
   int x = (src_position - border_texels_) /
@@ skipping 188 matching lines @@
   num_tiles_y_ = ComputeNumTiles(
       max_texture_size_.height(), total_size_.height(), border_texels_);
 }
 
 TilingData::BaseIterator::BaseIterator(const TilingData* tiling_data)
     : tiling_data_(tiling_data),
       index_x_(-1),
       index_y_(-1) {
 }
 
+TilingData::Iterator::Iterator() : BaseIterator(NULL) { done(); }
+
 TilingData::Iterator::Iterator(const TilingData* tiling_data,
                                const gfx::Rect& tiling_rect)
     : BaseIterator(tiling_data),
       left_(-1),
       right_(-1),
       bottom_(-1) {
   if (tiling_data_->num_tiles_x() <= 0 || tiling_data_->num_tiles_y() <= 0) {
     done();
     return;
   }
@@ skipping 117 matching lines @@
       }
     }
 
     if (index_y_ > consider_bottom_)
       done();
   }
 
   return *this;
 }
 
+TilingData::SpiralDifferenceIterator::SpiralDifferenceIterator()
+    : BaseIterator(NULL) {
+  done();
+}
+
 TilingData::SpiralDifferenceIterator::SpiralDifferenceIterator(
     const TilingData* tiling_data,
     const gfx::Rect& consider_rect,
     const gfx::Rect& ignore_rect,
     const gfx::Rect& center_rect)
     : BaseIterator(tiling_data),
       consider_left_(-1),
       consider_top_(-1),
       consider_right_(-1),
       consider_bottom_(-1),
@@ skipping 186 matching lines @@
   current_step_ = 0;
   direction_ = static_cast<Direction>((direction_ + 1) % 4);
 
   if (direction_ == RIGHT || direction_ == LEFT) {
     ++vertical_step_count_;
     ++horizontal_step_count_;
   }
 }
 
 }  // namespace cc