sky/engine/platform/graphics/filters/FEComposite.h

/*
 * Copyright (C) 2004, 2005, 2006, 2007 Nikolas Zimmermann <zimmermann@kde.org>
 * Copyright (C) 2004, 2005 Rob Buis <buis@kde.org>
 * Copyright (C) 2005 Eric Seidel <eric@webkit.org>
 * Copyright (C) 2013 Google Inc. All rights reserved.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public License
 * along with this library; see the file COPYING.LIB.  If not, write to
 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA 02110-1301, USA.
 */

#ifndef SKY_ENGINE_PLATFORM_GRAPHICS_FILTERS_FECOMPOSITE_H_
#define SKY_ENGINE_PLATFORM_GRAPHICS_FILTERS_FECOMPOSITE_H_

#include "sky/engine/platform/graphics/filters/Filter.h"
#include "sky/engine/platform/graphics/filters/FilterEffect.h"
#include "sky/engine/wtf/text/WTFString.h"

namespace blink {

enum CompositeOperationType {
    FECOMPOSITE_OPERATOR_UNKNOWN    = 0,
    FECOMPOSITE_OPERATOR_OVER       = 1,
    FECOMPOSITE_OPERATOR_IN         = 2,
    FECOMPOSITE_OPERATOR_OUT        = 3,
    FECOMPOSITE_OPERATOR_ATOP       = 4,
    FECOMPOSITE_OPERATOR_XOR        = 5,
    FECOMPOSITE_OPERATOR_ARITHMETIC = 6
};

class PLATFORM_EXPORT FEComposite : public FilterEffect {
public:
    static PassRefPtr<FEComposite> create(Filter*, const CompositeOperationType&, float, float, float, float);

    CompositeOperationType operation() const;
    bool setOperation(CompositeOperationType);

    float k1() const;
    bool setK1(float);

    float k2() const;
    bool setK2(float);

    float k3() const;
    bool setK3(float);

    float k4() const;
    bool setK4(float);

    virtual void correctFilterResultIfNeeded() override;

    virtual FloatRect determineAbsolutePaintRect(const FloatRect& requestedRect) override;

    virtual TextStream& externalRepresentation(TextStream&, int indention) const override;

    virtual PassRefPtr<SkImageFilter> createImageFilter(SkiaImageFilterBuilder*) override;
    virtual PassRefPtr<SkImageFilter> createImageFilterWithoutValidation(SkiaImageFilterBuilder*) override;

protected:
    virtual bool mayProduceInvalidPreMultipliedPixels() override { return m_type == FECOMPOSITE_OPERATOR_ARITHMETIC; }

private:
    FEComposite(Filter*, const CompositeOperationType&, float, float, float, float);

    virtual void applySoftware() override;
    PassRefPtr<SkImageFilter> createImageFilterInternal(SkiaImageFilterBuilder*, bool requiresPMColorValidation);

    inline void platformArithmeticSoftware(Uint8ClampedArray* source, Uint8ClampedArray* destination,
        float k1, float k2, float k3, float k4);
    template <int b1, int b4>
    static inline void computeArithmeticPixelsNeon(unsigned char* source, unsigned  char* destination,
        unsigned pixelArrayLength, float k1, float k2, float k3, float k4);
    static inline void platformArithmeticNeon(unsigned char* source, unsigned  char* destination,
        unsigned pixelArrayLength, float k1, float k2, float k3, float k4);

    CompositeOperationType m_type;
    float m_k1;
    float m_k2;
    float m_k3;
    float m_k4;
};

} // namespace blink

#endif  // SKY_ENGINE_PLATFORM_GRAPHICS_FILTERS_FECOMPOSITE_H_