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/*
* Copyright 2018 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#ifndef SkCoverageModePriv_DEFINED
#define SkCoverageModePriv_DEFINED
#include "SkBlendMode.h"
#include "SkCoverageMode.h"
const SkBlendMode gUncorrelatedCoverageToBlend[] = {
SkBlendMode::kSrcOver, // or DstOver
SkBlendMode::kSrcIn, // or kDstIn
SkBlendMode::kSrcOut,
SkBlendMode::kDstOut,
SkBlendMode::kXor,
};
#if 0
// Experimental idea to extend to overlap types
Master calculation = X(S,D) + Y(S,D) + Z(S,D)
enum class SkCoverageOverlap {
// X Y Z
kUncorrelated, // S*D S*(1-D) D*(1-S)
kConjoint, // min(S,D) max(S-D,0) max(D-S,0)
kDisjoint, // max(S+D-1,0) min(S,1-D) min(D,1-S)
kLast = kDisjoint
};
// The coverage modes each have a set of coefficients to be applied to the general equation (above)
//
// e.g.
// kXor+conjoint = max(S-D,0) + max(D-S,0) ==> abs(D-S)
//
kUnion, // 1,1,1
kIntersect, // 1,0,0
kDifference, // 0,1,0
kReverseDifference, // 0,0,1
kXor, // 0,1,1
#endif
#endif