Basic use implementation for MediaStream from Canvas: captureStream()

third_party/WebKit/Source/core/html/HTMLCanvasElement.h

 /*
  * Copyright (C) 2004, 2006, 2009, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2007 Alp Toker <alp@atoker.com>
  * Copyright (C) 2010 Torch Mobile (Beijing) Co. Ltd. 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.
@@ skipping 18 matching lines @@
 #define HTMLCanvasElement_h
 
 #include "bindings/core/v8/ScriptValue.h"
 #include "bindings/core/v8/UnionTypesCore.h"
 #include "core/CoreExport.h"
 #include "core/dom/DOMTypedArray.h"
 #include "core/dom/Document.h"
 #include "core/dom/DocumentVisibilityObserver.h"
 #include "core/fileapi/FileCallback.h"
 #include "core/html/HTMLElement.h"
+#include "core/html/canvas/CanvasDrawListener.h"
 #include "core/html/canvas/CanvasImageSource.h"
 #include "platform/geometry/FloatRect.h"
 #include "platform/geometry/IntSize.h"
 #include "platform/graphics/GraphicsTypes.h"
 #include "platform/graphics/GraphicsTypes3D.h"
 #include "platform/graphics/ImageBufferClient.h"
 #include "platform/heap/Handle.h"
 
 #define CanvasDefaultInterpolationQuality InterpolationLow
 
@@ skipping 45 matching lines @@
 
     bool isPaintable() const;
 
     static String toEncodingMimeType(const String& mimeType);
     String toDataURL(const String& mimeType, const ScriptValue& qualityArgument, ExceptionState&) const;
     String toDataURL(const String& mimeType, ExceptionState& exceptionState) const { return toDataURL(mimeType, ScriptValue(), exceptionState); }
 
     void toBlob(FileCallback*, const String& mimeType, const ScriptValue& qualityArgument, ExceptionState&);
     void toBlob(FileCallback* callback, const String& mimeType, ExceptionState& exceptionState) { return toBlob(callback, mimeType, ScriptValue(), exceptionState); }
 
+    // Used for canvas capture.
+    void addListener(CanvasDrawListener*);
+    void removeListener(CanvasDrawListener*);
+
     // Used for rendering
     void didDraw(const FloatRect&);
 
     void paint(GraphicsContext*, const LayoutRect&);
 
     SkCanvas* drawingCanvas() const;
     void disableDeferral() const;
     SkCanvas* existingDrawingCanvas() const;
 
     void setRenderingContext(PassOwnPtrWillBeRawPtr<CanvasRenderingContext>);
@@ skipping 72 matching lines @@
 
     PassOwnPtr<ImageBufferSurface> createImageBufferSurface(const IntSize& deviceSize, int* msaaSampleCount);
     void createImageBuffer();
     void createImageBufferInternal(PassOwnPtr<ImageBufferSurface> externalSurface);
     bool shouldUseDisplayList(const IntSize& deviceSize);
 
     void setSurfaceSize(const IntSize&);
 
     bool paintsIntoCanvasBuffer() const;
 
+    void notifyListenersCanvasChanged();
+
     ImageData* toImageData(SourceDrawingBuffer) const;
     String toDataURLInternal(const String& mimeType, const double& quality, SourceDrawingBuffer) const;
 
+    PersistentHeapHashSetWillBeHeapHashSet<WeakMember<CanvasDrawListener>> m_listeners;

[Justin Novosad, 2015/11/25 02:38:05]

I feel bad that you had to figure out how to declare this. That being said, I
believe you neglected to add this frankenmember to the trace method. I just
kicked off an oilpan try job to see.

[emircan, 2015/11/26 01:03:52]

Right, thanks for catching. I am adding. 

+
     IntSize m_size;
 
     OwnPtrWillBeMember<CanvasRenderingContext> m_context;
 
     bool m_ignoreReset;
     FloatRect m_dirtyRect;
 
     mutable intptr_t m_externallyAllocatedMemory;
 
     bool m_originClean;
 
     // It prevents HTMLCanvasElement::buffer() from continuously re-attempting to allocate an imageBuffer
     // after the first attempt failed.
     mutable bool m_didFailToCreateImageBuffer;
     bool m_imageBufferIsClear;
     OwnPtr<ImageBuffer> m_imageBuffer;
 
     mutable RefPtr<Image> m_copiedImage; // FIXME: This is temporary for platforms that have to copy the image buffer to render (and for CSSCanvasValue).
 };
 
 } // namespace blink
 
 #endif // HTMLCanvasElement_h