third_party/blink/renderer/core/html/canvas/canvas_rendering_context.h - chromium/src - Git at Google

 /*
  * Copyright (C) 2009 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
  *
  * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */

 #ifndef THIRD_PARTY_BLINK_RENDERER_CORE_HTML_CANVAS_CANVAS_RENDERING_CONTEXT_H_
 #define THIRD_PARTY_BLINK_RENDERER_CORE_HTML_CANVAS_CANVAS_RENDERING_CONTEXT_H_

 #include "base/macros.h"
 #include "third_party/blink/renderer/core/core_export.h"
 #include "third_party/blink/renderer/core/html/canvas/canvas_context_creation_attributes_core.h"
 #include "third_party/blink/renderer/core/html/canvas/html_canvas_element.h"
 #include "third_party/blink/renderer/core/layout/hit_test_canvas_result.h"
 #include "third_party/blink/renderer/core/offscreencanvas/offscreen_canvas.h"
 #include "third_party/blink/renderer/platform/graphics/canvas_color_params.h"
 #include "third_party/blink/renderer/platform/graphics/color_behavior.h"
 #include "third_party/blink/renderer/platform/scheduler/public/thread.h"
 #include "third_party/blink/renderer/platform/wtf/hash_set.h"
 #include "third_party/blink/renderer/platform/wtf/text/string_hash.h"
 #include "third_party/skia/include/core/SkColorSpace.h"
 #include "third_party/skia/include/core/SkImageInfo.h"

 namespace blink {

 class CanvasImageSource;
 class HTMLCanvasElement;
 class ImageBitmap;

 constexpr const char* kSRGBCanvasColorSpaceName = "srgb";
 constexpr const char* kRec2020CanvasColorSpaceName = "rec2020";
 constexpr const char* kP3CanvasColorSpaceName = "p3";

 constexpr const char* kRGBA8CanvasPixelFormatName = "8-8-8-8";
 constexpr const char* kRGB10A2CanvasPixelFormatName = "10-10-10-2";
 constexpr const char* kRGBA12CanvasPixelFormatName = "12-12-12-12";
 constexpr const char* kF16CanvasPixelFormatName = "float16";

 class CORE_EXPORT CanvasRenderingContext : public ScriptWrappable,
                                            public WebThread::TaskObserver {
   USING_PRE_FINALIZER(CanvasRenderingContext, Dispose);

  public:
   ~CanvasRenderingContext() override = default;

   // A Canvas can either be "2D" or "webgl" but never both. Requesting a context
   // with a type different from an existing will destroy the latter.
   enum ContextType {
     // Do not change assigned numbers of existing items: add new features to the
     // end of the list.
     kContext2d = 0,
     kContextExperimentalWebgl = 2,
     kContextWebgl = 3,
     kContextWebgl2 = 4,
     kContextImageBitmap = 5,
     kContextXRPresent = 6,
     kContextWebgl2Compute = 7,
     kContextTypeCount,
   };

   static ContextType ContextTypeFromId(const String& id);
   static ContextType ResolveContextTypeAliases(ContextType);

   CanvasRenderingContextHost* Host() const { return host_; }

   WTF::String ColorSpaceAsString() const;
   WTF::String PixelFormatAsString() const;

   const CanvasColorParams& ColorParams() const { return color_params_; }

   virtual scoped_refptr<StaticBitmapImage> GetImage(AccelerationHint) const = 0;
   virtual ContextType GetContextType() const = 0;
   virtual bool IsComposited() const = 0;
   virtual bool IsAccelerated() const = 0;
   virtual bool IsOriginTopLeft() const {
     // Canvas contexts have the origin of coordinates on the top left corner.
     // Accelerated resources (e.g. GPU textures) have their origin of
     // coordinates in the uppper left corner.
     return !IsAccelerated();
   }
   virtual bool ShouldAntialias() const { return false; }
   virtual void SetIsHidden(bool) = 0;
   virtual bool isContextLost() const { return true; }
   // TODO(fserb): remove SetCanvasGetContextResult.
   virtual void SetCanvasGetContextResult(RenderingContext&) { NOTREACHED(); };
   virtual void SetOffscreenCanvasGetContextResult(OffscreenRenderingContext&) {
     NOTREACHED();
   }
   virtual bool IsPaintable() const = 0;
   virtual void DidDraw(const SkIRect& dirty_rect);
   virtual void DidDraw();

   // Return true if the content is updated.
   virtual bool PaintRenderingResultsToCanvas(SourceDrawingBuffer) {
     return false;
   }

   virtual cc::Layer* CcLayer() const { return nullptr; }

   enum LostContextMode {
     kNotLostContext,

     // Lost context occurred at the graphics system level.
     kRealLostContext,

     // Lost context provoked by WEBGL_lose_context.
     kWebGLLoseContextLostContext,

     // Lost context occurred due to internal implementation reasons.
     kSyntheticLostContext,
   };
   virtual void LoseContext(LostContextMode) {}

   // This method gets called at the end of script tasks that modified
   // the contents of the canvas (called didDraw). It marks the completion
   // of a presentable frame.
   virtual void FinalizeFrame() {}

   void NeedsFinalizeFrame();

   // WebThread::TaskObserver implementation
   void DidProcessTask() override;
   void WillProcessTask() final {}

   // Canvas2D-specific interface
   virtual bool Is2d() const { return false; }
   virtual void RestoreCanvasMatrixClipStack(cc::PaintCanvas*) const {}
   virtual void Reset() {}
   virtual void ClearRect(double x, double y, double width, double height) {}
   virtual void DidSetSurfaceSize() {}
   virtual void SetShouldAntialias(bool) {}
   virtual unsigned HitRegionsCount() const { return 0; }
   virtual void setFont(const String&) {}
   virtual void StyleDidChange(const ComputedStyle* old_style,
                               const ComputedStyle& new_style) {}
   virtual HitTestCanvasResult* GetControlAndIdIfHitRegionExists(
       const LayoutPoint& location) {
     NOTREACHED();
     return HitTestCanvasResult::Create(String(), nullptr);
   }
   virtual String GetIdFromControl(const Element* element) { return String(); }
   virtual void ResetUsageTracking(){};

   // WebGL-specific interface
   virtual bool Is3d() const { return false; }
   virtual void SetFilterQuality(SkFilterQuality) { NOTREACHED(); }
   virtual void Reshape(int width, int height) { NOTREACHED(); }
   virtual void MarkLayerComposited() { NOTREACHED(); }
   virtual scoped_refptr<Uint8Array> PaintRenderingResultsToDataArray(
       SourceDrawingBuffer) {
     NOTREACHED();
     return nullptr;
   }
   virtual int ExternallyAllocatedBufferCountPerPixel() {
     NOTREACHED();
     return 0;
   }
   virtual IntSize DrawingBufferSize() const {
     NOTREACHED();
     return IntSize(0, 0);
   }

   // OffscreenCanvas-specific methods
   virtual void PushFrame() {}
   virtual ImageBitmap* TransferToImageBitmap(ScriptState*) { return nullptr; }

   bool WouldTaintOrigin(CanvasImageSource*, const SecurityOrigin*);
   void DidMoveToNewDocument(Document*);

   void DetachHost() { host_ = nullptr; }

   const CanvasContextCreationAttributesCore& CreationAttributes() const {
     return creation_attributes_;
   }

   void Trace(blink::Visitor*) override;
   virtual void Stop() = 0;

  protected:
   CanvasRenderingContext(CanvasRenderingContextHost*,
                          const CanvasContextCreationAttributesCore&);

  private:
   void Dispose();

   Member<CanvasRenderingContextHost> host_;
   HashSet<String> clean_urls_;
   HashSet<String> dirty_urls_;
   CanvasColorParams color_params_;
   CanvasContextCreationAttributesCore creation_attributes_;
   bool finalize_frame_scheduled_ = false;

   DISALLOW_COPY_AND_ASSIGN(CanvasRenderingContext);
 };

 }  // namespace blink

 #endif
	/*
	* Copyright (C) 2009 Apple Inc. All rights reserved.
	*
	* Redistribution and use in source and binary forms, with or without
	* modification, are permitted provided that the following conditions
	* are met:
	* 1. Redistributions of source code must retain the above copyright
	* notice, this list of conditions and the following disclaimer.
	* 2. Redistributions in binary form must reproduce the above copyright
	* notice, this list of conditions and the following disclaimer in the
	* documentation and/or other materials provided with the distribution.
	*
	* THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
	* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
	* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE COMPUTER, INC. OR
	* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
	* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
	* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
	* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
	* OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
	* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	*/

	#ifndef THIRD_PARTY_BLINK_RENDERER_CORE_HTML_CANVAS_CANVAS_RENDERING_CONTEXT_H_
	#define THIRD_PARTY_BLINK_RENDERER_CORE_HTML_CANVAS_CANVAS_RENDERING_CONTEXT_H_

	#include "base/macros.h"
	#include "third_party/blink/renderer/core/core_export.h"
	#include "third_party/blink/renderer/core/html/canvas/canvas_context_creation_attributes_core.h"
	#include "third_party/blink/renderer/core/html/canvas/html_canvas_element.h"
	#include "third_party/blink/renderer/core/layout/hit_test_canvas_result.h"
	#include "third_party/blink/renderer/core/offscreencanvas/offscreen_canvas.h"
	#include "third_party/blink/renderer/platform/graphics/canvas_color_params.h"
	#include "third_party/blink/renderer/platform/graphics/color_behavior.h"
	#include "third_party/blink/renderer/platform/scheduler/public/thread.h"
	#include "third_party/blink/renderer/platform/wtf/hash_set.h"
	#include "third_party/blink/renderer/platform/wtf/text/string_hash.h"
	#include "third_party/skia/include/core/SkColorSpace.h"
	#include "third_party/skia/include/core/SkImageInfo.h"

	namespace blink {

	class CanvasImageSource;
	class HTMLCanvasElement;
	class ImageBitmap;

	constexpr const char* kSRGBCanvasColorSpaceName = "srgb";
	constexpr const char* kRec2020CanvasColorSpaceName = "rec2020";
	constexpr const char* kP3CanvasColorSpaceName = "p3";

	constexpr const char* kRGBA8CanvasPixelFormatName = "8-8-8-8";
	constexpr const char* kRGB10A2CanvasPixelFormatName = "10-10-10-2";
	constexpr const char* kRGBA12CanvasPixelFormatName = "12-12-12-12";
	constexpr const char* kF16CanvasPixelFormatName = "float16";

	class CORE_EXPORT CanvasRenderingContext : public ScriptWrappable,
	public WebThread::TaskObserver {
	USING_PRE_FINALIZER(CanvasRenderingContext, Dispose);

	public:
	~CanvasRenderingContext() override = default;

	// A Canvas can either be "2D" or "webgl" but never both. Requesting a context
	// with a type different from an existing will destroy the latter.
	enum ContextType {
	// Do not change assigned numbers of existing items: add new features to the
	// end of the list.
	kContext2d = 0,
	kContextExperimentalWebgl = 2,
	kContextWebgl = 3,
	kContextWebgl2 = 4,
	kContextImageBitmap = 5,
	kContextXRPresent = 6,
	kContextWebgl2Compute = 7,
	kContextTypeCount,
	};

	static ContextType ContextTypeFromId(const String& id);
	static ContextType ResolveContextTypeAliases(ContextType);

	CanvasRenderingContextHost* Host() const { return host_; }

	WTF::String ColorSpaceAsString() const;
	WTF::String PixelFormatAsString() const;

	const CanvasColorParams& ColorParams() const { return color_params_; }

	virtual scoped_refptr<StaticBitmapImage> GetImage(AccelerationHint) const = 0;
	virtual ContextType GetContextType() const = 0;
	virtual bool IsComposited() const = 0;
	virtual bool IsAccelerated() const = 0;
	virtual bool IsOriginTopLeft() const {
	// Canvas contexts have the origin of coordinates on the top left corner.
	// Accelerated resources (e.g. GPU textures) have their origin of
	// coordinates in the uppper left corner.
	return !IsAccelerated();
	}
	virtual bool ShouldAntialias() const { return false; }
	virtual void SetIsHidden(bool) = 0;
	virtual bool isContextLost() const { return true; }
	// TODO(fserb): remove SetCanvasGetContextResult.
	virtual void SetCanvasGetContextResult(RenderingContext&) { NOTREACHED(); };
	virtual void SetOffscreenCanvasGetContextResult(OffscreenRenderingContext&) {
	NOTREACHED();
	}
	virtual bool IsPaintable() const = 0;
	virtual void DidDraw(const SkIRect& dirty_rect);
	virtual void DidDraw();

	// Return true if the content is updated.
	virtual bool PaintRenderingResultsToCanvas(SourceDrawingBuffer) {
	return false;
	}

	virtual cc::Layer* CcLayer() const { return nullptr; }

	enum LostContextMode {
	kNotLostContext,

	// Lost context occurred at the graphics system level.
	kRealLostContext,

	// Lost context provoked by WEBGL_lose_context.
	kWebGLLoseContextLostContext,

	// Lost context occurred due to internal implementation reasons.
	kSyntheticLostContext,
	};
	virtual void LoseContext(LostContextMode) {}

	// This method gets called at the end of script tasks that modified
	// the contents of the canvas (called didDraw). It marks the completion
	// of a presentable frame.
	virtual void FinalizeFrame() {}

	void NeedsFinalizeFrame();

	// WebThread::TaskObserver implementation
	void DidProcessTask() override;
	void WillProcessTask() final {}

	// Canvas2D-specific interface
	virtual bool Is2d() const { return false; }
	virtual void RestoreCanvasMatrixClipStack(cc::PaintCanvas*) const {}
	virtual void Reset() {}
	virtual void ClearRect(double x, double y, double width, double height) {}
	virtual void DidSetSurfaceSize() {}
	virtual void SetShouldAntialias(bool) {}
	virtual unsigned HitRegionsCount() const { return 0; }
	virtual void setFont(const String&) {}
	virtual void StyleDidChange(const ComputedStyle* old_style,
	const ComputedStyle& new_style) {}
	virtual HitTestCanvasResult* GetControlAndIdIfHitRegionExists(
	const LayoutPoint& location) {
	NOTREACHED();
	return HitTestCanvasResult::Create(String(), nullptr);
	}
	virtual String GetIdFromControl(const Element* element) { return String(); }
	virtual void ResetUsageTracking(){};

	// WebGL-specific interface
	virtual bool Is3d() const { return false; }
	virtual void SetFilterQuality(SkFilterQuality) { NOTREACHED(); }
	virtual void Reshape(int width, int height) { NOTREACHED(); }
	virtual void MarkLayerComposited() { NOTREACHED(); }
	virtual scoped_refptr<Uint8Array> PaintRenderingResultsToDataArray(
	SourceDrawingBuffer) {
	NOTREACHED();
	return nullptr;
	}
	virtual int ExternallyAllocatedBufferCountPerPixel() {
	NOTREACHED();
	return 0;
	}
	virtual IntSize DrawingBufferSize() const {
	NOTREACHED();
	return IntSize(0, 0);
	}

	// OffscreenCanvas-specific methods
	virtual void PushFrame() {}
	virtual ImageBitmap* TransferToImageBitmap(ScriptState*) { return nullptr; }

	bool WouldTaintOrigin(CanvasImageSource, const SecurityOrigin);
	void DidMoveToNewDocument(Document*);

	void DetachHost() { host_ = nullptr; }

	const CanvasContextCreationAttributesCore& CreationAttributes() const {
	return creation_attributes_;
	}

	void Trace(blink::Visitor*) override;
	virtual void Stop() = 0;

	protected:
	CanvasRenderingContext(CanvasRenderingContextHost*,
	const CanvasContextCreationAttributesCore&);

	private:
	void Dispose();

	Member<CanvasRenderingContextHost> host_;
	HashSet<String> clean_urls_;
	HashSet<String> dirty_urls_;
	CanvasColorParams color_params_;
	CanvasContextCreationAttributesCore creation_attributes_;
	bool finalize_frame_scheduled_ = false;

	DISALLOW_COPY_AND_ASSIGN(CanvasRenderingContext);
	};

	} // namespace blink

	#endif