src/gpu/effects/GrXfermodeFragmentProcessor.h

/*
 * Copyright 2015 Google Inc.
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */

#ifndef GrXfermodeFragmentProcessor_DEFINED
#define GrXfermodeFragmentProcessor_DEFINED

#include "SkRefCnt.h"
#include "SkBlendMode.h"

class GrFragmentProcessor;

namespace GrXfermodeFragmentProcessor {

/** The color input to the returned processor is treated as the src and the passed in processor is
    the dst. */
std::unique_ptr<GrFragmentProcessor> MakeFromDstProcessor(std::unique_ptr<GrFragmentProcessor> dst,
                                                          SkBlendMode mode);

/** The color input to the returned processor is treated as the dst and the passed in processor is
    the src. */
std::unique_ptr<GrFragmentProcessor> MakeFromSrcProcessor(std::unique_ptr<GrFragmentProcessor> src,
                                                          SkBlendMode mode);

/** Takes the input color, which is assumed to be unpremultiplied, passes it as an opaque color
    to both src and dst. The outputs of a src and dst are blended using mode and the original
    input's alpha is applied to the blended color to produce a premul output. */
std::unique_ptr<GrFragmentProcessor> MakeFromTwoProcessors(std::unique_ptr<GrFragmentProcessor> src,
                                                           std::unique_ptr<GrFragmentProcessor> dst,
                                                           SkBlendMode mode);

};

#endif