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