Source/WebCore/platform/graphics/Pattern.h

/*
 * Copyright (C) 2006-2021 Apple Inc.  All rights reserved.
 * Copyright (C) 2008 Eric Seidel <eric@webkit.org>
 * Copyright (C) 2007-2008 Torch Mobile, Inc.
 *
 * 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 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 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. 
 */

#pragma once

#include "AffineTransform.h"
#include "SourceImage.h"

#include <wtf/Ref.h>
#include <wtf/RefCounted.h>

#if USE(CG)
typedef struct CGPattern* CGPatternRef;
typedef RetainPtr<CGPatternRef> PlatformPatternPtr;
#elif USE(CAIRO)
typedef struct _cairo_pattern cairo_pattern_t;
typedef cairo_pattern_t* PlatformPatternPtr;
#endif

namespace WebCore {

class AffineTransform;
class GraphicsContext;

class Pattern final : public RefCounted<Pattern> {
public:
    struct Parameters {
        Parameters(bool repeatX = true, bool repeatY = true, AffineTransform patternSpaceTransform = { })
            : patternSpaceTransform(patternSpaceTransform)
            , repeatX(repeatX)
            , repeatY(repeatY)
        {
        }
        template<class Encoder> void encode(Encoder&) const;
        template<class Decoder> static std::optional<Parameters> decode(Decoder&);
        AffineTransform patternSpaceTransform;
        bool repeatX;
        bool repeatY;
    };

    WEBCORE_EXPORT static Ref<Pattern> create(SourceImage&& tileImage, const Parameters& = { });
    WEBCORE_EXPORT ~Pattern();

    const SourceImage& tileImage() const { return m_tileImage; }
    RefPtr<NativeImage> tileNativeImage() const { return m_tileImage.nativeImage(); }
    RefPtr<ImageBuffer> tileImageBuffer() const { return m_tileImage.imageBuffer(); }
    const Parameters& parameters() const { return m_parameters; }

    // Pattern space is an abstract space that maps to the default user space by the transformation 'userSpaceTransform'
    PlatformPatternPtr createPlatformPattern(const AffineTransform& userSpaceTransform) const;

    void setTileImage(SourceImage&& tileImage) { m_tileImage = WTFMove(tileImage); }
    void setPatternSpaceTransform(const AffineTransform&);

    const AffineTransform& patternSpaceTransform() const { return m_parameters.patternSpaceTransform; };
    bool repeatX() const { return m_parameters.repeatX; }
    bool repeatY() const { return m_parameters.repeatY; }

    template<class Encoder> void encode(Encoder&) const;
    template<class Decoder> static std::optional<Ref<Pattern>> decode(Decoder&);

private:
    Pattern(SourceImage&&, const Parameters&);

    SourceImage m_tileImage;
    Parameters m_parameters;
};

template<class Encoder>
void Pattern::Parameters::encode(Encoder& encoder) const
{
    encoder << patternSpaceTransform;
    encoder << repeatX;
    encoder << repeatY;
}

template<class Decoder>
std::optional<Pattern::Parameters> Pattern::Parameters::decode(Decoder& decoder)
{
    std::optional<AffineTransform> patternSpaceTransform;
    decoder >> patternSpaceTransform;
    if (!patternSpaceTransform)
        return std::nullopt;

    std::optional<bool> repeatX;
    decoder >> repeatX;
    if (!repeatX)
        return std::nullopt;

    std::optional<bool> repeatY;
    decoder >> repeatY;
    if (!repeatY)
        return std::nullopt;

    return {{ *repeatX, *repeatY, *patternSpaceTransform }};
}

template<class Encoder>
void Pattern::encode(Encoder& encoder) const
{
    encoder << m_tileImage;
    encoder << m_parameters;
}

template<class Decoder>
std::optional<Ref<Pattern>> Pattern::decode(Decoder& decoder)
{
    std::optional<SourceImage> tileImage;
    decoder >> tileImage;
    if (!tileImage)
        return std::nullopt;

    std::optional<Parameters> parameters;
    decoder >> parameters;
    if (!parameters)
        return std::nullopt;

    return Pattern::create(WTFMove(*tileImage), *parameters);
}

} //namespace