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* Copyright 2017 Google Inc.
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
#ifndef GrCCQuadraticShader_DEFINED
#define GrCCQuadraticShader_DEFINED
#include "src/gpu/ccpr/GrCCCoverageProcessor.h"
* This class renders the coverage of closed quadratic curves using the techniques outlined in
* "Resolution Independent Curve Rendering using Programmable Graphics Hardware" by Charles Loop and
* Jim Blinn:
* The provided curves must be monotonic with respect to the vector of their closing edge [P2 - P0].
* (Use GrCCGeometry::quadraticTo().)
class GrCCQuadraticShader : public GrCCCoverageProcessor::Shader {
void emitSetupCode(
GrGLSLVertexGeoBuilder*, const char* pts, const char** outHull4) const override;
void onEmitVaryings(
GrGLSLVaryingHandler*, GrGLSLVarying::Scope, SkString* code, const char* position,
const char* coverage, const char* cornerCoverage, const char* wind) override;
void emitFragmentCoverageCode(
GrGLSLFPFragmentBuilder*, const char* outputCoverage) const override;
void emitSampleMaskCode(GrGLSLFPFragmentBuilder*) const override;
void calcHullCoverage(SkString* code, const char* coordAndGrad, const char* d,
const char* outputCoverage) const;
const GrShaderVar fQCoordMatrix{"qcoord_matrix", kFloat2x2_GrSLType};
const GrShaderVar fQCoord0{"qcoord0", kFloat2_GrSLType};
GrGLSLVarying fCoord_fGrad;
GrGLSLVarying fEdge_fWind_fCorner;