1 /* 2 * Copyright (C) 2004, 2006, 2009, 2010 Apple Inc. All rights reserved. 3 * Copyright (C) 2007 Alp Toker <alp (at) atoker.com> 4 * Copyright (C) 2010 Torch Mobile (Beijing) Co. Ltd. All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY 16 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 18 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE COMPUTER, INC. OR 19 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 20 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 21 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 22 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY 23 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 25 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 */ 27 28 #ifndef HTMLCanvasElement_h 29 #define HTMLCanvasElement_h 30 31 #include "core/dom/Document.h" 32 #include "core/html/HTMLElement.h" 33 #include "core/html/canvas/CanvasImageSource.h" 34 #include "platform/geometry/FloatRect.h" 35 #include "platform/geometry/IntSize.h" 36 #include "platform/graphics/Canvas2DLayerBridge.h" 37 #include "platform/graphics/GraphicsTypes.h" 38 #include "platform/graphics/ImageBufferClient.h" 39 #include "platform/heap/Handle.h" 40 #include "wtf/Forward.h" 41 42 #define CanvasDefaultInterpolationQuality InterpolationLow 43 44 namespace WebCore { 45 46 class AffineTransform; 47 class CanvasContextAttributes; 48 class CanvasRenderingContext; 49 class GraphicsContext; 50 class GraphicsContextStateSaver; 51 class HTMLCanvasElement; 52 class Image; 53 class ImageData; 54 class ImageBuffer; 55 class ImageBufferSurface; 56 class IntSize; 57 58 class CanvasObserver : public WillBeGarbageCollectedMixin { 59 DECLARE_EMPTY_VIRTUAL_DESTRUCTOR_WILL_BE_REMOVED(CanvasObserver); 60 public: 61 virtual void canvasChanged(HTMLCanvasElement*, const FloatRect& changedRect) = 0; 62 virtual void canvasResized(HTMLCanvasElement*) = 0; 63 #if !ENABLE(OILPAN) 64 virtual void canvasDestroyed(HTMLCanvasElement*) = 0; 65 #endif 66 67 virtual void trace(Visitor*) { } 68 }; 69 70 class HTMLCanvasElement FINAL : public HTMLElement, public DocumentVisibilityObserver, public CanvasImageSource, public ImageBufferClient { 71 WILL_BE_USING_GARBAGE_COLLECTED_MIXIN(HTMLCanvasElement); 72 public: 73 DECLARE_NODE_FACTORY(HTMLCanvasElement); 74 virtual ~HTMLCanvasElement(); 75 76 void addObserver(CanvasObserver*); 77 void removeObserver(CanvasObserver*); 78 79 // Attributes and functions exposed to script 80 int width() const { return size().width(); } 81 int height() const { return size().height(); } 82 83 const IntSize& size() const { return m_size; } 84 85 void setWidth(int); 86 void setHeight(int); 87 void setAccelerationDisabled(bool accelerationDisabled) { m_accelerationDisabled = accelerationDisabled; } 88 bool accelerationDisabled() const { return m_accelerationDisabled; } 89 90 void setSize(const IntSize& newSize) 91 { 92 if (newSize == size()) 93 return; 94 m_ignoreReset = true; 95 setWidth(newSize.width()); 96 setHeight(newSize.height()); 97 m_ignoreReset = false; 98 reset(); 99 } 100 101 CanvasRenderingContext* getContext(const String&, CanvasContextAttributes* attributes = 0); 102 103 static String toEncodingMimeType(const String& mimeType); 104 String toDataURL(const String& mimeType, const double* quality, ExceptionState&) const; 105 String toDataURL(const String& mimeType, ExceptionState& exceptionState) const { return toDataURL(mimeType, 0, exceptionState); } 106 107 // Used for rendering 108 void didDraw(const FloatRect&); 109 void notifyObserversCanvasChanged(const FloatRect&); 110 111 void paint(GraphicsContext*, const LayoutRect&); 112 113 GraphicsContext* drawingContext() const; 114 GraphicsContext* existingDrawingContext() const; 115 116 CanvasRenderingContext* renderingContext() const { return m_context.get(); } 117 118 void ensureUnacceleratedImageBuffer(); 119 ImageBuffer* buffer() const; 120 Image* copiedImage() const; 121 void clearCopiedImage(); 122 PassRefPtrWillBeRawPtr<ImageData> getImageData() const; 123 void makePresentationCopy(); 124 void clearPresentationCopy(); 125 126 SecurityOrigin* securityOrigin() const; 127 bool originClean() const { return m_originClean; } 128 void setOriginTainted() { m_originClean = false; } 129 130 AffineTransform baseTransform() const; 131 132 bool is3D() const; 133 134 bool hasImageBuffer() const { return m_imageBuffer; } 135 bool hasValidImageBuffer() const; 136 void discardImageBuffer(); 137 138 bool shouldAccelerate(const IntSize&) const; 139 140 virtual const AtomicString imageSourceURL() const OVERRIDE; 141 142 virtual InsertionNotificationRequest insertedInto(ContainerNode*) OVERRIDE; 143 144 // DocumentVisibilityObserver implementation 145 virtual void didChangeVisibilityState(PageVisibilityState) OVERRIDE; 146 147 // CanvasImageSource implementation 148 virtual PassRefPtr<Image> getSourceImageForCanvas(SourceImageMode, SourceImageStatus*) const OVERRIDE; 149 virtual bool wouldTaintOrigin(SecurityOrigin*) const OVERRIDE; 150 virtual FloatSize sourceSize() const OVERRIDE; 151 152 // ImageBufferClient implementation 153 virtual void notifySurfaceInvalid() OVERRIDE; 154 155 virtual void trace(Visitor*) OVERRIDE; 156 157 protected: 158 virtual void didMoveToNewDocument(Document& oldDocument) OVERRIDE; 159 160 private: 161 explicit HTMLCanvasElement(Document&); 162 163 virtual void parseAttribute(const QualifiedName&, const AtomicString&) OVERRIDE; 164 virtual RenderObject* createRenderer(RenderStyle*) OVERRIDE; 165 virtual bool areAuthorShadowsAllowed() const OVERRIDE { return false; } 166 167 void reset(); 168 169 PassOwnPtr<ImageBufferSurface> createImageBufferSurface(const IntSize& deviceSize, int* msaaSampleCount); 170 void createImageBuffer(); 171 void createImageBufferInternal(); 172 void clearImageBuffer(); 173 174 void setSurfaceSize(const IntSize&); 175 176 bool paintsIntoCanvasBuffer() const; 177 178 void updateExternallyAllocatedMemory() const; 179 180 String toDataURLInternal(const String& mimeType, const double* quality, bool isSaving = false) const; 181 182 WillBeHeapHashSet<RawPtrWillBeWeakMember<CanvasObserver> > m_observers; 183 184 IntSize m_size; 185 186 OwnPtrWillBeMember<CanvasRenderingContext> m_context; 187 188 bool m_ignoreReset; 189 bool m_accelerationDisabled; 190 FloatRect m_dirtyRect; 191 192 mutable intptr_t m_externallyAllocatedMemory; 193 194 bool m_originClean; 195 196 // It prevents HTMLCanvasElement::buffer() from continuously re-attempting to allocate an imageBuffer 197 // after the first attempt failed. 198 mutable bool m_didFailToCreateImageBuffer; 199 mutable bool m_didClearImageBuffer; 200 OwnPtr<ImageBuffer> m_imageBuffer; 201 mutable OwnPtr<GraphicsContextStateSaver> m_contextStateSaver; 202 203 mutable RefPtr<Image> m_presentedImage; 204 mutable RefPtr<Image> m_copiedImage; // FIXME: This is temporary for platforms that have to copy the image buffer to render (and for CSSCanvasValue). 205 }; 206 207 } //namespace 208 209 #endif 210
