src/gpu/graphite/PaintParams.h

/*
 * Copyright 2022 Google LLC
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */

#ifndef skgpu_graphite_PaintParams_DEFINED
#define skgpu_graphite_PaintParams_DEFINED

#include "include/core/SkColor.h"
#include "include/core/SkPaint.h"

class SkPaintParamsKeyBuilder;
class SkPipelineDataGatherer;
class SkShader;
class SkKeyContext;

namespace skgpu::graphite {

// TBD: If occlusion culling is eliminated as a phase, we can easily move the paint conversion
// back to Device when the command is recorded (similar to SkPaint -> GrPaint), and then
// PaintParams is not required as an intermediate representation.
// NOTE: Only represents the shading state of an SkPaint. Style and complex effects (mask filters,
// image filters, path effects) must be handled higher up. AA is not tracked since everything is
// assumed to be anti-aliased.
class PaintParams {
public:
    PaintParams(const SkColor4f& color,
                sk_sp<SkBlender> finalBlender,
                sk_sp<SkShader>,
                sk_sp<SkColorFilter>,
                sk_sp<SkBlender> primitiveBlender,
                bool skipColorXform);
    explicit PaintParams(const SkPaint&,
                         sk_sp<SkBlender> primitiveBlender = nullptr,
                         bool skipColorXform = false);

    PaintParams(const PaintParams&);
    ~PaintParams();

    PaintParams& operator=(const PaintParams&);

    SkColor4f color() const { return fColor; }

    std::optional<SkBlendMode> asFinalBlendMode() const;
    SkBlender* finalBlender() const { return fFinalBlender.get(); }
    sk_sp<SkBlender> refFinalBlender() const;

    SkShader* shader() const { return fShader.get(); }
    sk_sp<SkShader> refShader() const;

    SkColorFilter* colorFilter() const { return fColorFilter.get(); }
    sk_sp<SkColorFilter> refColorFilter() const;

    SkBlender* primitiveBlender() const { return fPrimitiveBlender.get(); }
    sk_sp<SkBlender> refPrimitiveBlender() const;

    bool skipColorXform() const { return fSkipColorXform; }

    void toKey(const SkKeyContext&,
               SkPaintParamsKeyBuilder*,
               SkPipelineDataGatherer*) const;

private:
    SkColor4f            fColor;
    sk_sp<SkBlender>     fFinalBlender; // A nullptr here means SrcOver blending
    sk_sp<SkShader>      fShader;
    sk_sp<SkColorFilter> fColorFilter;
    // A nullptr fPrimitiveBlender means there's no primitive color blending and it is skipped.
    // In the case where there is primitive blending, the primitive color is the source color and
    // the dest is the paint's color (or the paint's shader's computed color).
    sk_sp<SkBlender>     fPrimitiveBlender;
    bool                 fSkipColorXform;

    // TODO: Will also store ColorFilter, dither, and any extra shader from an
    // active clipShader().
};

} // namespace skgpu

#endif // skgpu_PaintParams_DEFINED