src/gpu/ccpr/GrGSCoverageProcessor.h

/*
 * Copyright 2019 Google Inc.
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */

#ifndef GrGSCoverageProcessor_DEFINED
#define GrGSCoverageProcessor_DEFINED

#include "src/gpu/ccpr/GrCCCoverageProcessor.h"

/**
 * This class implements GrCCCoverageProcessor with analytic coverage using geometry shaders.
 */
class GrGSCoverageProcessor : public GrCCCoverageProcessor {
public:
    GrGSCoverageProcessor() : GrCCCoverageProcessor(kGrGSCoverageProcessor_ClassID) {
        this->setWillUseGeoShader();
    }

private:
    void reset(PrimitiveType, GrResourceProvider*) override;

    void getGLSLProcessorKey(const GrShaderCaps&, GrProcessorKeyBuilder* b) const override {
        SkDEBUGCODE(this->getDebugBloatKey(b));
        b->add32(((int)fPrimitiveType << 16) | (int)fSubpass);
    }

    void appendMesh(sk_sp<const GrGpuBuffer> instanceBuffer, int instanceCount, int baseInstance,
                    SkTArray<GrMesh>* out) const override;

    void draw(GrOpFlushState*, const GrPipeline&, const SkIRect scissorRects[], const GrMesh[],
              int meshCount, const SkRect& drawBounds) const override;

    GrGLSLPrimitiveProcessor* onCreateGLSLInstance(std::unique_ptr<Shader>) const override;

    // The geometry shader impl draws primitives in two subpasses. The first pass fills the interior
    // and does edge AA. The second pass does touch up on corner pixels.
    enum class Subpass : bool {
        kHulls,
        kCorners
    };

    Attribute fInputXOrYValues;
    mutable Subpass fSubpass = Subpass::kHulls;

    class Impl;
    class TriangleHullImpl;
    class CurveHullImpl;
    class CornerImpl;
};

#endif