src/cc/resources/picture.h

   1 // Copyright 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CC_RESOURCES_PICTURE_H_
   6 #define CC_RESOURCES_PICTURE_H_
   7
   8 #include <string>
   9 #include <utility>
  10 #include <vector>
  11
  12 #include "base/basictypes.h"
  13 #include "base/containers/hash_tables.h"
  14 #include "base/debug/trace_event.h"
  15 #include "base/lazy_instance.h"
  16 #include "base/logging.h"
  17 #include "base/memory/ref_counted.h"
  18 #include "base/memory/scoped_ptr.h"
  19 #include "base/threading/thread_checker.h"
  20 #include "cc/base/cc_export.h"
  21 #include "cc/base/region.h"
  22 #include "skia/ext/refptr.h"
  23 #include "third_party/skia/include/core/SkBBHFactory.h"
  24 #include "third_party/skia/include/core/SkPicture.h"
  25 #include "third_party/skia/include/record/SkRecording.h"
  26 #include "ui/gfx/rect.h"
  27
  28 class SkPixelRef;
  29
  30 namespace base {
  31 class Value;
  32 }
  33
  34 namespace skia {
  35 class AnalysisCanvas;
  36 }
  37
  38 namespace cc {
  39
  40 class ContentLayerClient;
  41
  42 class CC_EXPORT Picture
  43     : public base::RefCountedThreadSafe<Picture> {
  44  public:
  45   typedef std::pair<int, int> PixelRefMapKey;
  46   typedef std::vector<SkPixelRef*> PixelRefs;
  47   typedef base::hash_map<PixelRefMapKey, PixelRefs> PixelRefMap;
  48
  49   enum RecordingMode {
  50     RECORD_NORMALLY,
  51     RECORD_WITH_SK_NULL_CANVAS,
  52     RECORD_WITH_PAINTING_DISABLED,
  53     RECORD_WITH_SKRECORD,
  54     RECORDING_MODE_COUNT,  // Must be the last entry.
  55   };
  56
  57   static scoped_refptr<Picture> Create(
  58       const gfx::Rect& layer_rect,
  59       ContentLayerClient* client,
  60       const SkTileGridFactory::TileGridInfo& tile_grid_info,
  61       bool gather_pixels_refs,
  62       int num_raster_threads,
  63       RecordingMode recording_mode);
  64   static scoped_refptr<Picture> CreateFromValue(const base::Value* value);
  65   static scoped_refptr<Picture> CreateFromSkpValue(const base::Value* value);
  66
  67   gfx::Rect LayerRect() const { return layer_rect_; }
  68   gfx::Rect OpaqueRect() const { return opaque_rect_; }
  69
  70   // Get thread-safe clone for rasterizing with on a specific thread.
  71   Picture* GetCloneForDrawingOnThread(unsigned thread_index);
  72
  73   // Has Record() been called yet?
  74   bool HasRecording() const { return picture_.get() != NULL; }
  75
  76   bool IsSuitableForGpuRasterization() const;
  77
  78   // Apply this scale and raster the negated region into the canvas.
  79   // |negated_content_region| specifies the region to be clipped out of the
  80   // raster operation, i.e., the parts of the canvas which will not get drawn
  81   // to.
  82   int Raster(SkCanvas* canvas,
  83              SkDrawPictureCallback* callback,
  84              const Region& negated_content_region,
  85              float contents_scale);
  86
  87   // Draw the picture directly into the given canvas, without applying any
  88   // clip/scale/layer transformations.
  89   void Replay(SkCanvas* canvas);
  90
  91   scoped_ptr<base::Value> AsValue() const;
  92
  93   // This iterator imprecisely returns the set of pixel refs that are needed to
  94   // raster this layer rect from this picture.  Internally, pixel refs are
  95   // clumped into tile grid buckets, so there may be false positives.
  96   class CC_EXPORT PixelRefIterator {
  97    public:
  98     PixelRefIterator();
  99     PixelRefIterator(const gfx::Rect& layer_rect, const Picture* picture);
 100     ~PixelRefIterator();
 101
 102     SkPixelRef* operator->() const {
 103       DCHECK_LT(current_index_, current_pixel_refs_->size());
 104       return (*current_pixel_refs_)[current_index_];
 105     }
 106
 107     SkPixelRef* operator*() const {
 108       DCHECK_LT(current_index_, current_pixel_refs_->size());
 109       return (*current_pixel_refs_)[current_index_];
 110     }
 111
 112     PixelRefIterator& operator++();
 113     operator bool() const {
 114       return current_index_ < current_pixel_refs_->size();
 115     }
 116
 117    private:
 118     static base::LazyInstance<PixelRefs> empty_pixel_refs_;
 119     const Picture* picture_;
 120     const PixelRefs* current_pixel_refs_;
 121     unsigned current_index_;
 122
 123     gfx::Point min_point_;
 124     gfx::Point max_point_;
 125     int current_x_;
 126     int current_y_;
 127   };
 128
 129   void EmitTraceSnapshot() const;
 130   void EmitTraceSnapshotAlias(Picture* original) const;
 131
 132   bool WillPlayBackBitmaps() const { return picture_->willPlayBackBitmaps(); }
 133
 134  private:
 135   explicit Picture(const gfx::Rect& layer_rect);
 136   // This constructor assumes SkPicture is already ref'd and transfers
 137   // ownership to this picture.
 138   Picture(const skia::RefPtr<SkPicture>&,
 139           const gfx::Rect& layer_rect,
 140           const gfx::Rect& opaque_rect,
 141           const PixelRefMap& pixel_refs);
 142   // This constructor will call AdoptRef on the SkPicture.
 143   Picture(SkPicture*,
 144           const gfx::Rect& layer_rect,
 145           const gfx::Rect& opaque_rect);
 146   ~Picture();
 147
 148   // Make thread-safe clones for rasterizing with.
 149   void CloneForDrawing(int num_threads);
 150
 151   // Record a paint operation. To be able to safely use this SkPicture for
 152   // playback on a different thread this can only be called once.
 153   void Record(ContentLayerClient* client,
 154               const SkTileGridFactory::TileGridInfo& tile_grid_info,
 155               RecordingMode recording_mode);
 156
 157   // Gather pixel refs from recording.
 158   void GatherPixelRefs(const SkTileGridFactory::TileGridInfo& tile_grid_info);
 159
 160   gfx::Rect layer_rect_;
 161   gfx::Rect opaque_rect_;
 162   skia::RefPtr<SkPicture> picture_;
 163   scoped_ptr<const EXPERIMENTAL::SkPlayback> playback_;
 164
 165   typedef std::vector<scoped_refptr<Picture> > PictureVector;
 166   PictureVector clones_;
 167
 168   PixelRefMap pixel_refs_;
 169   gfx::Point min_pixel_cell_;
 170   gfx::Point max_pixel_cell_;
 171   gfx::Size cell_size_;
 172
 173   scoped_refptr<base::debug::ConvertableToTraceFormat>
 174     AsTraceableRasterData(float scale) const;
 175   scoped_refptr<base::debug::ConvertableToTraceFormat>
 176     AsTraceableRecordData() const;
 177
 178   base::ThreadChecker raster_thread_checker_;
 179
 180   friend class base::RefCountedThreadSafe<Picture>;
 181   friend class PixelRefIterator;
 182   DISALLOW_COPY_AND_ASSIGN(Picture);
 183 };
 184
 185 }  // namespace cc
 186
 187 #endif  // CC_RESOURCES_PICTURE_H_