WebCore/HTMLCanvasElement.h

   1 /*
   2  * Copyright (C) 2004, 2006 Apple Computer, 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 #include "IntSize.h"
  34
  35 namespace WebCore {
  36
  37 class CanvasRenderingContext2D;
  38 typedef CanvasRenderingContext2D CanvasRenderingContext;
  39 class FloatPoint;
  40 class FloatRect;
  41 class FloatSize;
  42 class GraphicsContext;
  43 class HTMLCanvasElement;
  44 class ImageBuffer;
  45 class IntPoint;
  46 class IntSize;
  47
  48 class CanvasObserver {
  49 public:
  50     virtual ~CanvasObserver() {};
  51
  52     virtual void canvasChanged(HTMLCanvasElement* element, const FloatRect& changedRect) = 0;
  53     virtual void canvasResized(HTMLCanvasElement* element) = 0;
  54 };
  55
  56 class HTMLCanvasElement : public HTMLElement {
  57 public:
  58     HTMLCanvasElement(const QualifiedName&, Document*);
  59     virtual ~HTMLCanvasElement();
  60
  61 #if ENABLE(DASHBOARD_SUPPORT)
  62     virtual HTMLTagStatus endTagRequirement() const;
  63     virtual int tagPriority() const;
  64 #endif
  65
  66     int width() const { return m_size.width(); }
  67     int height() const { return m_size.height(); }
  68     void setWidth(int);
  69     void setHeight(int);
  70
  71     String toDataURL(const String& mimeType, ExceptionCode&);
  72
  73     CanvasRenderingContext* getContext(const String&);
  74
  75     virtual void parseMappedAttribute(MappedAttribute*);
  76     virtual RenderObject* createRenderer(RenderArena*, RenderStyle*);
  77
  78     IntSize size() const { return m_size; }
  79     void setSize(const IntSize& size)
  80     {
  81         if (size == m_size)
  82             return;
  83         m_ignoreReset = true;
  84         setWidth(size.width());
  85         setHeight(size.height());
  86         m_ignoreReset = false;
  87         reset();
  88     }
  89
  90     void willDraw(const FloatRect&);
  91
  92     void paint(GraphicsContext*, const IntRect&);
  93
  94     GraphicsContext* drawingContext() const;
  95
  96     ImageBuffer* buffer() const;
  97
  98     IntRect convertLogicalToDevice(const FloatRect&) const;
  99     IntSize convertLogicalToDevice(const FloatSize&) const;
 100     IntPoint convertLogicalToDevice(const FloatPoint&) const;
 101
 102     void setOriginTainted() { m_originClean = false; }
 103     bool originClean() const { return m_originClean; }
 104
 105     static const float MaxCanvasArea;
 106
 107     void setObserver(CanvasObserver* o) { m_observer = o; }
 108
 109     TransformationMatrix baseTransform() const;
 110 private:
 111     void createImageBuffer() const;
 112     void reset();
 113
 114     bool m_rendererIsCanvas;
 115
 116     OwnPtr<CanvasRenderingContext2D> m_2DContext;
 117     IntSize m_size;
 118     CanvasObserver* m_observer;
 119
 120     bool m_originClean;
 121     bool m_ignoreReset;
 122     FloatRect m_dirtyRect;
 123
 124     // m_createdImageBuffer means we tried to malloc the buffer.  We didn't necessarily get it.
 125     mutable bool m_createdImageBuffer;
 126     mutable OwnPtr<ImageBuffer> m_imageBuffer;
 127 };
 128
 129 } //namespace
 130
 131 #endif