Source/platform/graphics/DrawLooper.h

/*
 * Copyright (C) 2013 Google Inc. All rights reserved.
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 * modification, are permitted provided that the following conditions are
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 *
 *     * Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
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 * copyright notice, this list of conditions and the following disclaimer
 * in the documentation and/or other materials provided with the
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 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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#ifndef DrawLooper_h
#define DrawLooper_h

#include "platform/PlatformExport.h"
#include "wtf/Noncopyable.h"
#include "wtf/RefPtr.h"

class SkDrawLooper;
class SkLayerDrawLooper;

namespace WebCore {

class Color;
class FloatSize;

class PLATFORM_EXPORT DrawLooper {
    // Implementing the copy constructor properly would require writing code to
    // copy the underlying SkDrawLooper.
    WTF_MAKE_NONCOPYABLE(DrawLooper);

public:
    enum ShadowTransformMode {
        ShadowRespectsTransforms,
        ShadowIgnoresTransforms
    };
    enum ShadowAlphaMode {
        ShadowRespectsAlpha,
        ShadowIgnoresAlpha
    };

    DrawLooper();
    ~DrawLooper();

    // Callees should not modify this looper other than to iterate over it.
    // A downcast to SkLayerDrawLooper* is tantamount to a const_cast.
    SkDrawLooper* skDrawLooper() const;

    void addUnmodifiedContent();
    void addShadow(const FloatSize& offset, float blur, const Color&,
        ShadowTransformMode = ShadowRespectsTransforms,
        ShadowAlphaMode = ShadowRespectsAlpha);

private:
    RefPtr<SkLayerDrawLooper> m_skDrawLooper;
};

} // namespace WebCore

#endif // DrawLooper_h