image.h

linux下开源浏览器WebKit的源码,市面上的很多商用浏览器都是移植自WebKit

/*
 * Copyright (C) 2006 Samuel Weinig ([e-mail])
 * Copyright (C) 2004, 2005, 2006 Apple Computer, 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 Image_h
#define Image_h

#include "Color.h"
#include "GraphicsTypes.h"
#include "ImageSource.h"
#include "IntRect.h"
#include <wtf/RefPtr.h>
#include <wtf/PassRefPtr.h>
#include "SharedBuffer.h"

#if PLATFORM(MAC)
#ifdef __OBJC__
@class NSImage;
#else
class NSImage;
#endif
#endif

#if PLATFORM(CG)
struct CGContext;
#endif

#if PLATFORM(WIN)
typedef struct tagSIZE SIZE;
typedef SIZE* LPSIZE;
typedef struct HBITMAP__ *HBITMAP;
#endif

#if PLATFORM(SKIA)
class NativeImageSkia;
#endif

#if PLATFORM(QT)
#include <QPixmap>
#endif

namespace WebCore {

class TransformationMatrix;
class FloatPoint;
class FloatRect;
class FloatSize;
class GraphicsContext;
class SharedBuffer;
class String;

// This class gets notified when an image creates or destroys decoded frames and when it advances animation frames.
class ImageObserver;

class Image : public RefCounted<Image> {
    friend class GeneratedImage;
    friend class GraphicsContext;
public:
    virtual ~Image();
    
    static PassRefPtr<Image> create(ImageObserver* = 0);
    static PassRefPtr<Image> loadPlatformResource(const char* name);
    static bool supportsType(const String&); 

    virtual bool isBitmapImage() const { return false; }

    // Derived classes should override this if they can assure that 
    // the image contains only resources from its own security origin.
    virtual bool hasSingleSecurityOrigin() const { return false; }

    static Image* nullImage();
    bool isNull() const { return size().isEmpty(); }

    // These are only used for SVGImage right now
    virtual void setContainerSize(const IntSize&) { }
    virtual bool usesContainerSize() const { return false; }
    virtual bool hasRelativeWidth() const { return false; }
    virtual bool hasRelativeHeight() const { return false; }

    virtual IntSize size() const = 0;
    IntRect rect() const { return IntRect(IntPoint(), size()); }
    int width() const { return size().width(); }
    int height() const { return size().height(); }

    bool setData(PassRefPtr<SharedBuffer> data, bool allDataReceived);
    virtual bool dataChanged(bool /*allDataReceived*/) { return false; }
    
    virtual String filenameExtension() const { return String(); } // null string if unknown

    virtual void destroyDecodedData(bool destroyAll = true) = 0;
    virtual unsigned decodedSize() const = 0;

    SharedBuffer* data() { return m_data.get(); }

    // It may look unusual that there is no start animation call as public API.  This is because
    // we start and stop animating lazily.  Animation begins whenever someone draws the image.  It will
    // automatically pause once all observers no longer want to render the image anywhere.
    virtual void stopAnimation() {}
    virtual void resetAnimation() {}
    
    // Typically the CachedImage that owns us.
    ImageObserver* imageObserver() const { return m_imageObserver; }

    enum TileRule { StretchTile, RoundTile, RepeatTile };

    virtual NativeImagePtr nativeImageForCurrentFrame() { return 0; }
    
#if PLATFORM(MAC)
    // Accessors for native image formats.
    virtual NSImage* getNSImage() { return 0; }
    virtual CFDataRef getTIFFRepresentation() { return 0; }
#endif

#if PLATFORM(CG)
    virtual CGImageRef getCGImageRef() { return 0; }
#endif

#if PLATFORM(WIN)
    virtual bool getHBITMAP(HBITMAP) { return false; }
    virtual bool getHBITMAPOfSize(HBITMAP, LPSIZE) { return false; }
#endif

protected:
    Image(ImageObserver* = 0);

    static void fillWithSolidColor(GraphicsContext* ctxt, const FloatRect& dstRect, const Color& color, CompositeOperator op);

#if PLATFORM(WIN)
    virtual void drawFrameMatchingSourceSize(GraphicsContext*, const FloatRect& dstRect, const IntSize& srcSize, CompositeOperator) { }
#endif
    virtual void draw(GraphicsContext*, const FloatRect& dstRect, const FloatRect& srcRect, CompositeOperator) = 0;
    void drawTiled(GraphicsContext*, const FloatRect& dstRect, const FloatPoint& srcPoint, const FloatSize& tileSize, CompositeOperator);
    void drawTiled(GraphicsContext*, const FloatRect& dstRect, const FloatRect& srcRect, TileRule hRule, TileRule vRule, CompositeOperator);

    // Supporting tiled drawing
    virtual bool mayFillWithSolidColor() { return false; }
    virtual Color solidColor() const { return Color(); }
    
    virtual void startAnimation(bool /*catchUpIfNecessary*/ = true) { }
    
    virtual void drawPattern(GraphicsContext*, const FloatRect& srcRect, const TransformationMatrix& patternTransform,
                             const FloatPoint& phase, CompositeOperator, const FloatRect& destRect);
#if PLATFORM(CG)
    // These are private to CG.  Ideally they would be only in the .cpp file, but the callback requires access
    // to the private function nativeImageForCurrentFrame()
    static void drawPatternCallback(void* info, CGContext*);
#endif
    
protected:
    RefPtr<SharedBuffer> m_data; // The encoded raw data for the image. 
    ImageObserver* m_imageObserver;
};

}

#endif