Extract subpixel offsets from composited layer transforms when possible.

cc/playback/raster_source.h

 // Copyright 2014 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_PLAYBACK_RASTER_SOURCE_H_
 #define CC_PLAYBACK_RASTER_SOURCE_H_
 
 #include <stddef.h>
 
 #include <vector>
 
 #include "base/macros.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/threading/thread_checker.h"
 #include "base/trace_event/memory_allocator_dump.h"
 #include "base/trace_event/memory_dump_provider.h"
 #include "cc/base/cc_export.h"
 #include "cc/debug/rendering_stats_instrumentation.h"
 #include "cc/playback/display_list_recording_source.h"
 #include "skia/ext/analysis_canvas.h"
 #include "third_party/skia/include/core/SkPicture.h"
+#include "ui/gfx/geometry/vector2d_f.h"
 
 namespace cc {
 class DisplayItemList;
 class DrawImage;
 class ImageDecodeController;
 
 class CC_EXPORT RasterSource : public base::trace_event::MemoryDumpProvider,
                                public base::RefCountedThreadSafe<RasterSource> {
  public:
   static scoped_refptr<RasterSource> CreateFromDisplayListRecordingSource(
@@ skipping 24 matching lines @@
                               const gfx::Rect& canvas_rect,
                               float contents_scale,
                               bool include_images) const;
 
   // Returns whether the given rect at given scale is of solid color in
   // this raster source, as well as the solid color value.
   bool PerformSolidColorAnalysis(const gfx::Rect& content_rect,
                                  float contents_scale,
                                  SkColor* color) const;
 
+  void SetSubpixelOffset(const gfx::Vector2dF& subpixel_offset) { subpixel_offset_ = subpixel_offset; }
+
   // Returns true iff the whole raster source is of solid color.
   bool IsSolidColor() const;
 
   // Returns the color of the raster source if it is solid color. The results
   // are unspecified if IsSolidColor returns false.
   SkColor GetSolidColor() const;
 
   // Returns the size of this raster source.
   gfx::Size GetSize() const;
 
@@ skipping 83 matching lines @@
                     float contents_scale) const;
 
   void PrepareForPlaybackToCanvas(SkCanvas* canvas,
                                   const gfx::Rect& canvas_bitmap_rect,
                                   const gfx::Rect& canvas_playback_rect,
                                   float contents_scale) const;
 
   // Used to ensure that memory dump logic always happens on the same thread.
   base::ThreadChecker memory_dump_thread_checker_;
 
+  gfx::Vector2dF subpixel_offset_;
+
   DISALLOW_COPY_AND_ASSIGN(RasterSource);
 };
 
 }  // namespace cc
 
 #endif  // CC_PLAYBACK_RASTER_SOURCE_H_