1 /* 2 * Copyright 2017 Google Inc. 3 * 4 * Use of this source code is governed by a BSD-style license that can be 5 * found in the LICENSE file. 6 */ 7 8 #include "SkBlendModePriv.h" 9 #include "SkRasterPipeline.h" 10 11 bool SkBlendMode_SupportsCoverageAsAlpha(SkBlendMode mode) { 12 switch (mode) { 13 case SkBlendMode::kDst: 14 case SkBlendMode::kSrcOver: 15 case SkBlendMode::kDstOver: 16 case SkBlendMode::kDstOut: 17 case SkBlendMode::kSrcATop: 18 case SkBlendMode::kXor: 19 case SkBlendMode::kPlus: 20 return true; 21 default: 22 break; 23 } 24 return false; 25 } 26 27 struct CoeffRec { 28 SkBlendModeCoeff fSrc; 29 SkBlendModeCoeff fDst; 30 }; 31 32 const CoeffRec gCoeffs[] = { 33 { SkBlendModeCoeff::kZero, SkBlendModeCoeff::kZero }, 34 { SkBlendModeCoeff::kOne, SkBlendModeCoeff::kZero }, 35 { SkBlendModeCoeff::kZero, SkBlendModeCoeff::kOne }, 36 { SkBlendModeCoeff::kOne, SkBlendModeCoeff::kISA }, 37 { SkBlendModeCoeff::kIDA, SkBlendModeCoeff::kOne }, 38 { SkBlendModeCoeff::kDA, SkBlendModeCoeff::kZero }, 39 { SkBlendModeCoeff::kZero, SkBlendModeCoeff::kSA }, 40 { SkBlendModeCoeff::kIDA, SkBlendModeCoeff::kZero }, 41 { SkBlendModeCoeff::kZero, SkBlendModeCoeff::kISA }, 42 { SkBlendModeCoeff::kDA, SkBlendModeCoeff::kISA }, 43 { SkBlendModeCoeff::kIDA, SkBlendModeCoeff::kSA }, 44 { SkBlendModeCoeff::kIDA, SkBlendModeCoeff::kISA }, 45 46 { SkBlendModeCoeff::kOne, SkBlendModeCoeff::kOne }, 47 { SkBlendModeCoeff::kZero, SkBlendModeCoeff::kSC }, 48 { SkBlendModeCoeff::kOne, SkBlendModeCoeff::kISC }, // screen 49 }; 50 51 bool SkBlendMode_AsCoeff(SkBlendMode mode, SkBlendModeCoeff* src, SkBlendModeCoeff* dst) { 52 if (mode > SkBlendMode::kScreen) { 53 return false; 54 } 55 if (src) { 56 *src = gCoeffs[static_cast<int>(mode)].fSrc; 57 } 58 if (dst) { 59 *dst = gCoeffs[static_cast<int>(mode)].fDst; 60 } 61 return true; 62 } 63 64 void SkBlendMode_AppendStagesNoClamp(SkBlendMode mode, SkRasterPipeline* p) { 65 auto stage = SkRasterPipeline::srcover; 66 switch (mode) { 67 case SkBlendMode::kClear: stage = SkRasterPipeline::clear; break; 68 case SkBlendMode::kSrc: return; // This stage is a no-op. 69 case SkBlendMode::kDst: stage = SkRasterPipeline::move_dst_src; break; 70 case SkBlendMode::kSrcOver: stage = SkRasterPipeline::srcover; break; 71 case SkBlendMode::kDstOver: stage = SkRasterPipeline::dstover; break; 72 case SkBlendMode::kSrcIn: stage = SkRasterPipeline::srcin; break; 73 case SkBlendMode::kDstIn: stage = SkRasterPipeline::dstin; break; 74 case SkBlendMode::kSrcOut: stage = SkRasterPipeline::srcout; break; 75 case SkBlendMode::kDstOut: stage = SkRasterPipeline::dstout; break; 76 case SkBlendMode::kSrcATop: stage = SkRasterPipeline::srcatop; break; 77 case SkBlendMode::kDstATop: stage = SkRasterPipeline::dstatop; break; 78 case SkBlendMode::kXor: stage = SkRasterPipeline::xor_; break; 79 case SkBlendMode::kPlus: stage = SkRasterPipeline::plus_; break; 80 case SkBlendMode::kModulate: stage = SkRasterPipeline::modulate; break; 81 82 case SkBlendMode::kScreen: stage = SkRasterPipeline::screen; break; 83 case SkBlendMode::kOverlay: stage = SkRasterPipeline::overlay; break; 84 case SkBlendMode::kDarken: stage = SkRasterPipeline::darken; break; 85 case SkBlendMode::kLighten: stage = SkRasterPipeline::lighten; break; 86 case SkBlendMode::kColorDodge: stage = SkRasterPipeline::colordodge; break; 87 case SkBlendMode::kColorBurn: stage = SkRasterPipeline::colorburn; break; 88 case SkBlendMode::kHardLight: stage = SkRasterPipeline::hardlight; break; 89 case SkBlendMode::kSoftLight: stage = SkRasterPipeline::softlight; break; 90 case SkBlendMode::kDifference: stage = SkRasterPipeline::difference; break; 91 case SkBlendMode::kExclusion: stage = SkRasterPipeline::exclusion; break; 92 case SkBlendMode::kMultiply: stage = SkRasterPipeline::multiply; break; 93 94 case SkBlendMode::kHue: stage = SkRasterPipeline::hue; break; 95 case SkBlendMode::kSaturation: stage = SkRasterPipeline::saturation; break; 96 case SkBlendMode::kColor: stage = SkRasterPipeline::color; break; 97 case SkBlendMode::kLuminosity: stage = SkRasterPipeline::luminosity; break; 98 } 99 p->append(stage); 100 } 101 102 void SkBlendMode_AppendClampIfNeeded(SkBlendMode mode, SkRasterPipeline* p) { 103 if (mode == SkBlendMode::kPlus) { 104 // Both clamp_a and clamp_1 would preserve premultiplication invariants here, 105 // so we pick clamp_1 for being a smidge faster. 106 p->append(SkRasterPipeline::clamp_1); 107 } 108 } 109 110 SkPM4f SkBlendMode_Apply(SkBlendMode mode, const SkPM4f& src, const SkPM4f& dst) { 111 // special-case simple/common modes... 112 switch (mode) { 113 case SkBlendMode::kClear: return {{ 0, 0, 0, 0 }}; 114 case SkBlendMode::kSrc: return src; 115 case SkBlendMode::kDst: return dst; 116 case SkBlendMode::kSrcOver: 117 return SkPM4f::From4f(src.to4f() + dst.to4f() * Sk4f(1 - src.a())); 118 default: 119 break; 120 } 121 122 SkRasterPipeline_<256> p; 123 SkPM4f src_storage = src, 124 dst_storage = dst, 125 result_storage, 126 *src_ctx = &src_storage, 127 *dst_ctx = &dst_storage, 128 *res_ctx = &result_storage; 129 130 p.append(SkRasterPipeline::load_f32, &dst_ctx); 131 p.append(SkRasterPipeline::move_src_dst); 132 p.append(SkRasterPipeline::load_f32, &src_ctx); 133 SkBlendMode_AppendStages(mode, &p); 134 p.append(SkRasterPipeline::store_f32, &res_ctx); 135 p.run(0, 0, 1); 136 return result_storage; 137 } 138
