cc/raster/raster_source.h - chromium/src - Git at Google

 // 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_RASTER_RASTER_SOURCE_H_
 #define CC_RASTER_RASTER_SOURCE_H_

 #include <stddef.h>

 #include <memory>
 #include <vector>

 #include "base/macros.h"
 #include "cc/cc_export.h"
 #include "cc/debug/rendering_stats_instrumentation.h"
 #include "cc/layers/recording_source.h"
 #include "cc/paint/image_id.h"
 #include "skia/ext/analysis_canvas.h"
 #include "third_party/skia/include/core/SkPicture.h"
 #include "ui/gfx/color_space.h"

 namespace gfx {
 class AxisTransform2d;
 }  // namespace gfx

 namespace cc {
 class DisplayItemList;
 class DrawImage;
 class ImageDecodeCache;

 class CC_EXPORT RasterSource : public base::RefCountedThreadSafe<RasterSource> {
  public:
   struct CC_EXPORT PlaybackSettings {
     PlaybackSettings();
     PlaybackSettings(const PlaybackSettings&);
     PlaybackSettings(PlaybackSettings&&);
     ~PlaybackSettings();

     // If set to true, this indicates that the canvas has already been
     // rasterized into. This means that the canvas cannot be cleared safely.
     bool playback_to_shared_canvas;

     // If set to true, none of the images will be rasterized.
     bool skip_images;

     // If set to true, we will use an image hijack canvas, which enables
     // compositor image caching.
     bool use_image_hijack_canvas;

     // If non-empty, an image hijack canvas will be used to skip these images
     // during raster.
     // TODO(khushalsagar): Consolidate more settings for playback here? See
     // crbug.com/691076.
     SkImageIdFlatSet images_to_skip;
   };

   static scoped_refptr<RasterSource> CreateFromRecordingSource(
       const RecordingSource* other,
       bool can_use_lcd_text);

   // Helper function to apply a few common operations before passing the canvas
   // to the shorter version. This is useful for rastering into tiles.
   // canvas is expected to be backed by a tile, with a default state.
   // raster_transform will be applied to the display list, rastering the list
   // into the "content space".
   // canvas_bitmap_rect defines the extent of the tile in the content space,
   // i.e. contents in the rect will be cropped and translated onto the canvas.
   // canvas_playback_rect can be used to replay only part of the recording in,
   // the content space, so only a sub-rect of the tile gets rastered.
   void PlaybackToCanvas(SkCanvas* canvas,
                         const gfx::ColorSpace& target_color_space,
                         const gfx::Rect& canvas_bitmap_rect,
                         const gfx::Rect& canvas_playback_rect,
                         const gfx::AxisTransform2d& raster_transform,
                         const PlaybackSettings& settings) const;

   // Raster this RasterSource into the given canvas. Canvas states such as
   // CTM and clip region will be respected. This function will replace pixels
   // in the clip region without blending. It is assumed that existing pixels
   // may be uninitialized and will be cleared before playback.
   //
   // Virtual for testing.
   //
   // Note that this should only be called after the image decode controller has
   // been set, which happens during commit.
   virtual void PlaybackToCanvas(SkCanvas* canvas,
                                 const gfx::ColorSpace& target_color_space,
                                 const PlaybackSettings& settings) 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;

   // 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;

   // Populate the given list with all images that may overlap the given
   // rect in layer space. The returned draw images' matrices are modified as if
   // they were being using during raster at scale |raster_scale|.
   void GetDiscardableImagesInRect(const gfx::Rect& layer_rect,
                                   float contents_scale,
                                   const gfx::ColorSpace& target_color_space,
                                   std::vector<DrawImage>* images) const;

   // Return true iff this raster source can raster the given rect in layer
   // space.
   bool CoversRect(const gfx::Rect& layer_rect) const;

   // Returns true if this raster source has anything to rasterize.
   virtual bool HasRecordings() const;

   // Valid rectangle in which everything is recorded and can be rastered from.
   virtual gfx::Rect RecordedViewport() const;

   gfx::Rect GetRectForImage(PaintImage::Id image_id) const;

   // Tracing functionality.
   virtual void DidBeginTracing();
   virtual void AsValueInto(base::trace_event::TracedValue* array) const;
   virtual sk_sp<SkPicture> GetFlattenedPicture();
   virtual size_t GetMemoryUsage() const;

   // Return true if LCD anti-aliasing may be used when rastering text.
   virtual bool CanUseLCDText() const;

   scoped_refptr<RasterSource> CreateCloneWithoutLCDText() const;

   // Image decode controller should be set once. Its lifetime has to exceed that
   // of the raster source, since the raster source will access it during raster.
   void set_image_decode_cache(ImageDecodeCache* image_decode_cache) {
     DCHECK(image_decode_cache);
     image_decode_cache_ = image_decode_cache;
   }

  protected:
   friend class base::RefCountedThreadSafe<RasterSource>;

   RasterSource(const RecordingSource* other, bool can_use_lcd_text);
   RasterSource(const RasterSource* other, bool can_use_lcd_text);
   virtual ~RasterSource();

   // These members are const as this raster source may be in use on another
   // thread and so should not be touched after construction.
   const scoped_refptr<DisplayItemList> display_list_;
   const size_t painter_reported_memory_usage_;
   const SkColor background_color_;
   const bool requires_clear_;
   const bool can_use_lcd_text_;
   const bool is_solid_color_;
   const SkColor solid_color_;
   const gfx::Rect recorded_viewport_;
   const gfx::Size size_;
   const bool clear_canvas_with_debug_color_;
   const int slow_down_raster_scale_factor_for_debug_;

   // In practice, this is only set once before raster begins, so it's ok with
   // respect to threading.
   ImageDecodeCache* image_decode_cache_;

  private:
   void RasterCommon(SkCanvas* canvas,
                     SkPicture::AbortCallback* callback = nullptr) const;

   void PrepareForPlaybackToCanvas(SkCanvas* canvas) const;

   DISALLOW_COPY_AND_ASSIGN(RasterSource);
 };

 }  // namespace cc

 #endif  // CC_RASTER_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_RASTER_RASTER_SOURCE_H_
	#define CC_RASTER_RASTER_SOURCE_H_

	#include <stddef.h>

	#include <memory>
	#include <vector>

	#include "base/macros.h"
	#include "cc/cc_export.h"
	#include "cc/debug/rendering_stats_instrumentation.h"
	#include "cc/layers/recording_source.h"
	#include "cc/paint/image_id.h"
	#include "skia/ext/analysis_canvas.h"
	#include "third_party/skia/include/core/SkPicture.h"
	#include "ui/gfx/color_space.h"

	namespace gfx {
	class AxisTransform2d;
	} // namespace gfx

	namespace cc {
	class DisplayItemList;
	class DrawImage;
	class ImageDecodeCache;

	class CC_EXPORT RasterSource : public base::RefCountedThreadSafe<RasterSource> {
	public:
	struct CC_EXPORT PlaybackSettings {
	PlaybackSettings();
	PlaybackSettings(const PlaybackSettings&);
	PlaybackSettings(PlaybackSettings&&);
	~PlaybackSettings();

	// If set to true, this indicates that the canvas has already been
	// rasterized into. This means that the canvas cannot be cleared safely.
	bool playback_to_shared_canvas;

	// If set to true, none of the images will be rasterized.
	bool skip_images;

	// If set to true, we will use an image hijack canvas, which enables
	// compositor image caching.
	bool use_image_hijack_canvas;

	// If non-empty, an image hijack canvas will be used to skip these images
	// during raster.
	// TODO(khushalsagar): Consolidate more settings for playback here? See
	// crbug.com/691076.
	SkImageIdFlatSet images_to_skip;
	};

	static scoped_refptr<RasterSource> CreateFromRecordingSource(
	const RecordingSource* other,
	bool can_use_lcd_text);

	// Helper function to apply a few common operations before passing the canvas
	// to the shorter version. This is useful for rastering into tiles.
	// canvas is expected to be backed by a tile, with a default state.
	// raster_transform will be applied to the display list, rastering the list
	// into the "content space".
	// canvas_bitmap_rect defines the extent of the tile in the content space,
	// i.e. contents in the rect will be cropped and translated onto the canvas.
	// canvas_playback_rect can be used to replay only part of the recording in,
	// the content space, so only a sub-rect of the tile gets rastered.
	void PlaybackToCanvas(SkCanvas* canvas,
	const gfx::ColorSpace& target_color_space,
	const gfx::Rect& canvas_bitmap_rect,
	const gfx::Rect& canvas_playback_rect,
	const gfx::AxisTransform2d& raster_transform,
	const PlaybackSettings& settings) const;

	// Raster this RasterSource into the given canvas. Canvas states such as
	// CTM and clip region will be respected. This function will replace pixels
	// in the clip region without blending. It is assumed that existing pixels
	// may be uninitialized and will be cleared before playback.
	//
	// Virtual for testing.
	//
	// Note that this should only be called after the image decode controller has
	// been set, which happens during commit.
	virtual void PlaybackToCanvas(SkCanvas* canvas,
	const gfx::ColorSpace& target_color_space,
	const PlaybackSettings& settings) 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;

	// 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;

	// Populate the given list with all images that may overlap the given
	// rect in layer space. The returned draw images' matrices are modified as if
	// they were being using during raster at scale \|raster_scale\|.
	void GetDiscardableImagesInRect(const gfx::Rect& layer_rect,
	float contents_scale,
	const gfx::ColorSpace& target_color_space,
	std::vector<DrawImage>* images) const;

	// Return true iff this raster source can raster the given rect in layer
	// space.
	bool CoversRect(const gfx::Rect& layer_rect) const;

	// Returns true if this raster source has anything to rasterize.
	virtual bool HasRecordings() const;

	// Valid rectangle in which everything is recorded and can be rastered from.
	virtual gfx::Rect RecordedViewport() const;

	gfx::Rect GetRectForImage(PaintImage::Id image_id) const;

	// Tracing functionality.
	virtual void DidBeginTracing();
	virtual void AsValueInto(base::trace_event::TracedValue* array) const;
	virtual sk_sp<SkPicture> GetFlattenedPicture();
	virtual size_t GetMemoryUsage() const;

	// Return true if LCD anti-aliasing may be used when rastering text.
	virtual bool CanUseLCDText() const;

	scoped_refptr<RasterSource> CreateCloneWithoutLCDText() const;

	// Image decode controller should be set once. Its lifetime has to exceed that
	// of the raster source, since the raster source will access it during raster.
	void set_image_decode_cache(ImageDecodeCache* image_decode_cache) {
	DCHECK(image_decode_cache);
	image_decode_cache_ = image_decode_cache;
	}

	protected:
	friend class base::RefCountedThreadSafe<RasterSource>;

	RasterSource(const RecordingSource* other, bool can_use_lcd_text);
	RasterSource(const RasterSource* other, bool can_use_lcd_text);
	virtual ~RasterSource();

	// These members are const as this raster source may be in use on another
	// thread and so should not be touched after construction.
	const scoped_refptr<DisplayItemList> display_list_;
	const size_t painter_reported_memory_usage_;
	const SkColor background_color_;
	const bool requires_clear_;
	const bool can_use_lcd_text_;
	const bool is_solid_color_;
	const SkColor solid_color_;
	const gfx::Rect recorded_viewport_;
	const gfx::Size size_;
	const bool clear_canvas_with_debug_color_;
	const int slow_down_raster_scale_factor_for_debug_;

	// In practice, this is only set once before raster begins, so it's ok with
	// respect to threading.
	ImageDecodeCache* image_decode_cache_;

	private:
	void RasterCommon(SkCanvas* canvas,
	SkPicture::AbortCallback* callback = nullptr) const;

	void PrepareForPlaybackToCanvas(SkCanvas* canvas) const;

	DISALLOW_COPY_AND_ASSIGN(RasterSource);
	};

	} // namespace cc

	#endif // CC_RASTER_RASTER_SOURCE_H_