WebCore/html/HTMLCanvasElement.h

   1 /*
   2  * Copyright (C) 2004, 2006, 2009 Apple Inc. All rights reserved.
   3  * Copyright (C) 2007 Alp Toker <alp@atoker.com>
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  *
  14  * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
  15  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  17  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
  18  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  19  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  20  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  21  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
  22  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  24  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  25  */
  26
  27 #ifndef HTMLCanvasElement_h
  28 #define HTMLCanvasElement_h
  29
  30 #include "TransformationMatrix.h"
  31 #include "FloatRect.h"
  32 #include "HTMLElement.h"
  33 #if ENABLE(3D_CANVAS)
  34 #include "GraphicsContext3D.h"
  35 #endif
  36 #include "IntSize.h"
  37
  38 namespace WebCore {
  39
  40 class CanvasRenderingContext;
  41 class FloatPoint;
  42 class FloatRect;
  43 class FloatSize;
  44 class GraphicsContext;
  45 class HTMLCanvasElement;
  46 class ImageBuffer;
  47 class IntPoint;
  48 class IntSize;
  49
  50 class CanvasObserver {
  51 public:
  52     virtual ~CanvasObserver() { }
  53
  54     virtual void canvasChanged(HTMLCanvasElement*, const FloatRect& changedRect) = 0;
  55     virtual void canvasResized(HTMLCanvasElement*) = 0;
  56     virtual void canvasDestroyed(HTMLCanvasElement*) = 0;
  57 };
  58
  59 class HTMLCanvasElement : public HTMLElement {
  60 public:
  61     HTMLCanvasElement(const QualifiedName&, Document*);
  62     virtual ~HTMLCanvasElement();
  63
  64     int width() const { return m_size.width(); }
  65     int height() const { return m_size.height(); }
  66     void setWidth(int);
  67     void setHeight(int);
  68
  69     String toDataURL(const String& mimeType, ExceptionCode&);
  70
  71     CanvasRenderingContext* getContext(const String&);
  72
  73     const IntSize& size() const { return m_size; }
  74     void setSize(const IntSize& size)
  75     {
  76         if (size == m_size)
  77             return;
  78         m_ignoreReset = true;
  79         setWidth(size.width());
  80         setHeight(size.height());
  81         m_ignoreReset = false;
  82         reset();
  83     }
  84
  85     void willDraw(const FloatRect&);
  86
  87     void paint(GraphicsContext*, const IntRect&);
  88
  89     GraphicsContext* drawingContext() const;
  90
  91     ImageBuffer* buffer() const;
  92
  93     IntRect convertLogicalToDevice(const FloatRect&) const;
  94     IntSize convertLogicalToDevice(const FloatSize&) const;
  95     IntPoint convertLogicalToDevice(const FloatPoint&) const;
  96
  97     void setOriginTainted() { m_originClean = false; }
  98     bool originClean() const { return m_originClean; }
  99
 100     void setObserver(CanvasObserver* observer) { m_observer = observer; }
 101
 102     TransformationMatrix baseTransform() const;
 103
 104     CanvasRenderingContext* renderingContext() const { return m_context.get(); }
 105
 106 #if ENABLE(3D_CANVAS)
 107     bool is3D() const;
 108 #endif
 109
 110 private:
 111 #if ENABLE(DASHBOARD_SUPPORT)
 112     virtual HTMLTagStatus endTagRequirement() const;
 113     virtual int tagPriority() const;
 114 #endif
 115
 116     virtual void parseMappedAttribute(MappedAttribute*);
 117     virtual RenderObject* createRenderer(RenderArena*, RenderStyle*);
 118
 119     void createImageBuffer() const;
 120     void reset();
 121
 122     static const float MaxCanvasArea;
 123
 124     bool m_rendererIsCanvas;
 125
 126     OwnPtr<CanvasRenderingContext> m_context;
 127     IntSize m_size;
 128     CanvasObserver* m_observer;
 129
 130     bool m_originClean;
 131     bool m_ignoreReset;
 132     FloatRect m_dirtyRect;
 133
 134     // m_createdImageBuffer means we tried to malloc the buffer.  We didn't necessarily get it.
 135     mutable bool m_createdImageBuffer;
 136     mutable OwnPtr<ImageBuffer> m_imageBuffer;
 137 };
 138
 139 } //namespace
 140
 141 #endif