| /* |
| * Copyright 2014 Google Inc. |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #include "effects/GrPorterDuffXferProcessor.h" |
| |
| #include "GrBlend.h" |
| #include "GrCaps.h" |
| #include "GrPipeline.h" |
| #include "GrProcessor.h" |
| #include "GrProcOptInfo.h" |
| #include "GrTypes.h" |
| #include "GrXferProcessor.h" |
| #include "glsl/GrGLSLBlend.h" |
| #include "glsl/GrGLSLFragmentShaderBuilder.h" |
| #include "glsl/GrGLSLProgramDataManager.h" |
| #include "glsl/GrGLSLUniformHandler.h" |
| #include "glsl/GrGLSLXferProcessor.h" |
| #include <utility> |
| |
| /** |
| * Wraps the shader outputs and HW blend state that comprise a Porter Duff blend mode with coverage. |
| */ |
| struct BlendFormula { |
| public: |
| /** |
| * Values the shader can write to primary and secondary outputs. These must all be modulated by |
| * coverage to support mixed samples. The XP will ignore the multiplies when not using coverage. |
| */ |
| enum OutputType { |
| kNone_OutputType, //<! 0 |
| kCoverage_OutputType, //<! inputCoverage |
| kModulate_OutputType, //<! inputColor * inputCoverage |
| kSAModulate_OutputType, //<! inputColor.a * inputCoverage |
| kISAModulate_OutputType, //<! (1 - inputColor.a) * inputCoverage |
| kISCModulate_OutputType, //<! (1 - inputColor) * inputCoverage |
| |
| kLast_OutputType = kISCModulate_OutputType |
| }; |
| |
| enum Properties { |
| kModifiesDst_Property = 1, |
| kUsesDstColor_Property = 1 << 1, |
| kUsesInputColor_Property = 1 << 2, |
| kCanTweakAlphaForCoverage_Property = 1 << 3, |
| |
| kLast_Property = kCanTweakAlphaForCoverage_Property |
| }; |
| |
| BlendFormula& operator =(const BlendFormula& other) { |
| fData = other.fData; |
| return *this; |
| } |
| |
| bool operator ==(const BlendFormula& other) const { |
| return fData == other.fData; |
| } |
| |
| bool hasSecondaryOutput() const { return kNone_OutputType != fSecondaryOutputType; } |
| bool modifiesDst() const { return SkToBool(fProps & kModifiesDst_Property); } |
| bool usesDstColor() const { return SkToBool(fProps & kUsesDstColor_Property); } |
| bool usesInputColor() const { return SkToBool(fProps & kUsesInputColor_Property); } |
| bool canTweakAlphaForCoverage() const { |
| return SkToBool(fProps & kCanTweakAlphaForCoverage_Property); |
| } |
| |
| /** |
| * Deduce the properties of a compile-time constant BlendFormula. |
| */ |
| template<OutputType PrimaryOut, OutputType SecondaryOut, |
| GrBlendEquation BlendEquation, GrBlendCoeff SrcCoeff, GrBlendCoeff DstCoeff> |
| struct get_properties : std::integral_constant<Properties, static_cast<Properties>( |
| |
| (GR_BLEND_MODIFIES_DST(BlendEquation, SrcCoeff, DstCoeff) ? |
| kModifiesDst_Property : 0) | |
| |
| (GR_BLEND_COEFFS_USE_DST_COLOR(SrcCoeff, DstCoeff) ? |
| kUsesDstColor_Property : 0) | |
| |
| ((PrimaryOut >= kModulate_OutputType && GR_BLEND_COEFFS_USE_SRC_COLOR(SrcCoeff,DstCoeff)) || |
| (SecondaryOut >= kModulate_OutputType && GR_BLEND_COEFF_REFS_SRC2(DstCoeff)) ? |
| kUsesInputColor_Property : 0) | // We assert later that SrcCoeff doesn't ref src2. |
| |
| (kModulate_OutputType == PrimaryOut && |
| kNone_OutputType == SecondaryOut && |
| GR_BLEND_CAN_TWEAK_ALPHA_FOR_COVERAGE(BlendEquation, SrcCoeff, DstCoeff) ? |
| kCanTweakAlphaForCoverage_Property : 0))> { |
| |
| // The provided formula should already be optimized. |
| GR_STATIC_ASSERT((kNone_OutputType == PrimaryOut) == |
| !GR_BLEND_COEFFS_USE_SRC_COLOR(SrcCoeff, DstCoeff)); |
| GR_STATIC_ASSERT(!GR_BLEND_COEFF_REFS_SRC2(SrcCoeff)); |
| GR_STATIC_ASSERT((kNone_OutputType == SecondaryOut) == |
| !GR_BLEND_COEFF_REFS_SRC2(DstCoeff)); |
| GR_STATIC_ASSERT(PrimaryOut != SecondaryOut || kNone_OutputType == PrimaryOut); |
| GR_STATIC_ASSERT(kNone_OutputType != PrimaryOut || kNone_OutputType == SecondaryOut); |
| }; |
| |
| union { |
| struct { |
| // We allot the enums one more bit than they require because MSVC seems to sign-extend |
| // them when the top bit is set. (This is in violation of the C++03 standard 9.6/4) |
| OutputType fPrimaryOutputType : 4; |
| OutputType fSecondaryOutputType : 4; |
| GrBlendEquation fBlendEquation : 6; |
| GrBlendCoeff fSrcCoeff : 6; |
| GrBlendCoeff fDstCoeff : 6; |
| Properties fProps : 32 - (4 + 4 + 6 + 6 + 6); |
| }; |
| uint32_t fData; |
| }; |
| |
| GR_STATIC_ASSERT(kLast_OutputType < (1 << 3)); |
| GR_STATIC_ASSERT(kLast_GrBlendEquation < (1 << 5)); |
| GR_STATIC_ASSERT(kLast_GrBlendCoeff < (1 << 5)); |
| GR_STATIC_ASSERT(kLast_Property < (1 << 6)); |
| }; |
| |
| GR_STATIC_ASSERT(4 == sizeof(BlendFormula)); |
| |
| GR_MAKE_BITFIELD_OPS(BlendFormula::Properties); |
| |
| /** |
| * Initialize a compile-time constant BlendFormula and automatically deduce fProps. |
| */ |
| #define INIT_BLEND_FORMULA(PRIMARY_OUT, SECONDARY_OUT, BLEND_EQUATION, SRC_COEFF, DST_COEFF) \ |
| {{{PRIMARY_OUT, \ |
| SECONDARY_OUT, \ |
| BLEND_EQUATION, SRC_COEFF, DST_COEFF, \ |
| BlendFormula::get_properties<PRIMARY_OUT, SECONDARY_OUT, \ |
| BLEND_EQUATION, SRC_COEFF, DST_COEFF>::value}}} |
| |
| /** |
| * When there is no coverage, or the blend mode can tweak alpha for coverage, we use the standard |
| * Porter Duff formula. |
| */ |
| #define COEFF_FORMULA(SRC_COEFF, DST_COEFF) \ |
| INIT_BLEND_FORMULA(BlendFormula::kModulate_OutputType, \ |
| BlendFormula::kNone_OutputType, \ |
| kAdd_GrBlendEquation, SRC_COEFF, DST_COEFF) |
| |
| /** |
| * Basic coeff formula similar to COEFF_FORMULA but we will make the src f*Sa. This is used in |
| * LCD dst-out. |
| */ |
| #define COEFF_FORMULA_SA_MODULATE(SRC_COEFF, DST_COEFF) \ |
| INIT_BLEND_FORMULA(BlendFormula::kSAModulate_OutputType, \ |
| BlendFormula::kNone_OutputType, \ |
| kAdd_GrBlendEquation, SRC_COEFF, DST_COEFF) |
| |
| /** |
| * When the coeffs are (Zero, Zero), we clear the dst. This formula has its own macro so we can set |
| * the primary output type to none. |
| */ |
| #define DST_CLEAR_FORMULA \ |
| INIT_BLEND_FORMULA(BlendFormula::kNone_OutputType, \ |
| BlendFormula::kNone_OutputType, \ |
| kAdd_GrBlendEquation, kZero_GrBlendCoeff, kZero_GrBlendCoeff) |
| |
| /** |
| * When the coeffs are (Zero, One), we don't write to the dst at all. This formula has its own macro |
| * so we can set the primary output type to none. |
| */ |
| #define NO_DST_WRITE_FORMULA \ |
| INIT_BLEND_FORMULA(BlendFormula::kNone_OutputType, \ |
| BlendFormula::kNone_OutputType, \ |
| kAdd_GrBlendEquation, kZero_GrBlendCoeff, kOne_GrBlendCoeff) |
| |
| /** |
| * When there is coverage, the equation with f=coverage is: |
| * |
| * D' = f * (S * srcCoeff + D * dstCoeff) + (1-f) * D |
| * |
| * This can be rewritten as: |
| * |
| * D' = f * S * srcCoeff + D * (1 - [f * (1 - dstCoeff)]) |
| * |
| * To implement this formula, we output [f * (1 - dstCoeff)] for the secondary color and replace the |
| * HW dst coeff with IS2C. |
| * |
| * Xfer modes: dst-atop (Sa!=1) |
| */ |
| #define COVERAGE_FORMULA(ONE_MINUS_DST_COEFF_MODULATE_OUTPUT, SRC_COEFF) \ |
| INIT_BLEND_FORMULA(BlendFormula::kModulate_OutputType, \ |
| ONE_MINUS_DST_COEFF_MODULATE_OUTPUT, \ |
| kAdd_GrBlendEquation, SRC_COEFF, kIS2C_GrBlendCoeff) |
| |
| /** |
| * When there is coverage and the src coeff is Zero, the equation with f=coverage becomes: |
| * |
| * D' = f * D * dstCoeff + (1-f) * D |
| * |
| * This can be rewritten as: |
| * |
| * D' = D - D * [f * (1 - dstCoeff)] |
| * |
| * To implement this formula, we output [f * (1 - dstCoeff)] for the primary color and use a reverse |
| * subtract HW blend equation with coeffs of (DC, One). |
| * |
| * Xfer modes: clear, dst-out (Sa=1), dst-in (Sa!=1), modulate (Sc!=1) |
| */ |
| #define COVERAGE_SRC_COEFF_ZERO_FORMULA(ONE_MINUS_DST_COEFF_MODULATE_OUTPUT) \ |
| INIT_BLEND_FORMULA(ONE_MINUS_DST_COEFF_MODULATE_OUTPUT, \ |
| BlendFormula::kNone_OutputType, \ |
| kReverseSubtract_GrBlendEquation, kDC_GrBlendCoeff, kOne_GrBlendCoeff) |
| |
| /** |
| * When there is coverage and the dst coeff is Zero, the equation with f=coverage becomes: |
| * |
| * D' = f * S * srcCoeff + (1-f) * D |
| * |
| * To implement this formula, we output [f] for the secondary color and replace the HW dst coeff |
| * with IS2A. (Note that we can avoid dual source blending when Sa=1 by using ISA.) |
| * |
| * Xfer modes (Sa!=1): src, src-in, src-out |
| */ |
| #define COVERAGE_DST_COEFF_ZERO_FORMULA(SRC_COEFF) \ |
| INIT_BLEND_FORMULA(BlendFormula::kModulate_OutputType, \ |
| BlendFormula::kCoverage_OutputType, \ |
| kAdd_GrBlendEquation, SRC_COEFF, kIS2A_GrBlendCoeff) |
| |
| /** |
| * This table outlines the blend formulas we will use with each xfermode, with and without coverage, |
| * with and without an opaque input color. Optimization properties are deduced at compile time so we |
| * can make runtime decisions quickly. RGB coverage is not supported. |
| */ |
| static const BlendFormula gBlendTable[2][2][(int)SkBlendMode::kLastCoeffMode + 1] = { |
| |
| /*>> No coverage, input color unknown <<*/ {{ |
| |
| /* clear */ DST_CLEAR_FORMULA, |
| /* src */ COEFF_FORMULA( kOne_GrBlendCoeff, kZero_GrBlendCoeff), |
| /* dst */ NO_DST_WRITE_FORMULA, |
| /* src-over */ COEFF_FORMULA( kOne_GrBlendCoeff, kISA_GrBlendCoeff), |
| /* dst-over */ COEFF_FORMULA( kIDA_GrBlendCoeff, kOne_GrBlendCoeff), |
| /* src-in */ COEFF_FORMULA( kDA_GrBlendCoeff, kZero_GrBlendCoeff), |
| /* dst-in */ COEFF_FORMULA( kZero_GrBlendCoeff, kSA_GrBlendCoeff), |
| /* src-out */ COEFF_FORMULA( kIDA_GrBlendCoeff, kZero_GrBlendCoeff), |
| /* dst-out */ COEFF_FORMULA( kZero_GrBlendCoeff, kISA_GrBlendCoeff), |
| /* src-atop */ COEFF_FORMULA( kDA_GrBlendCoeff, kISA_GrBlendCoeff), |
| /* dst-atop */ COEFF_FORMULA( kIDA_GrBlendCoeff, kSA_GrBlendCoeff), |
| /* xor */ COEFF_FORMULA( kIDA_GrBlendCoeff, kISA_GrBlendCoeff), |
| /* plus */ COEFF_FORMULA( kOne_GrBlendCoeff, kOne_GrBlendCoeff), |
| /* modulate */ COEFF_FORMULA( kZero_GrBlendCoeff, kSC_GrBlendCoeff), |
| /* screen */ COEFF_FORMULA( kOne_GrBlendCoeff, kISC_GrBlendCoeff), |
| |
| }, /*>> Has coverage, input color unknown <<*/ { |
| |
| /* clear */ COVERAGE_SRC_COEFF_ZERO_FORMULA(BlendFormula::kCoverage_OutputType), |
| /* src */ COVERAGE_DST_COEFF_ZERO_FORMULA(kOne_GrBlendCoeff), |
| /* dst */ NO_DST_WRITE_FORMULA, |
| /* src-over */ COEFF_FORMULA( kOne_GrBlendCoeff, kISA_GrBlendCoeff), |
| /* dst-over */ COEFF_FORMULA( kIDA_GrBlendCoeff, kOne_GrBlendCoeff), |
| /* src-in */ COVERAGE_DST_COEFF_ZERO_FORMULA(kDA_GrBlendCoeff), |
| /* dst-in */ COVERAGE_SRC_COEFF_ZERO_FORMULA(BlendFormula::kISAModulate_OutputType), |
| /* src-out */ COVERAGE_DST_COEFF_ZERO_FORMULA(kIDA_GrBlendCoeff), |
| /* dst-out */ COEFF_FORMULA( kZero_GrBlendCoeff, kISA_GrBlendCoeff), |
| /* src-atop */ COEFF_FORMULA( kDA_GrBlendCoeff, kISA_GrBlendCoeff), |
| /* dst-atop */ COVERAGE_FORMULA(BlendFormula::kISAModulate_OutputType, kIDA_GrBlendCoeff), |
| /* xor */ COEFF_FORMULA( kIDA_GrBlendCoeff, kISA_GrBlendCoeff), |
| /* plus */ COEFF_FORMULA( kOne_GrBlendCoeff, kOne_GrBlendCoeff), |
| /* modulate */ COVERAGE_SRC_COEFF_ZERO_FORMULA(BlendFormula::kISCModulate_OutputType), |
| /* screen */ COEFF_FORMULA( kOne_GrBlendCoeff, kISC_GrBlendCoeff), |
| |
| }}, /*>> No coverage, input color opaque <<*/ {{ |
| |
| /* clear */ DST_CLEAR_FORMULA, |
| /* src */ COEFF_FORMULA( kOne_GrBlendCoeff, kZero_GrBlendCoeff), |
| /* dst */ NO_DST_WRITE_FORMULA, |
| /* src-over */ COEFF_FORMULA( kOne_GrBlendCoeff, kZero_GrBlendCoeff), |
| /* dst-over */ COEFF_FORMULA( kIDA_GrBlendCoeff, kOne_GrBlendCoeff), |
| /* src-in */ COEFF_FORMULA( kDA_GrBlendCoeff, kZero_GrBlendCoeff), |
| /* dst-in */ NO_DST_WRITE_FORMULA, |
| /* src-out */ COEFF_FORMULA( kIDA_GrBlendCoeff, kZero_GrBlendCoeff), |
| /* dst-out */ DST_CLEAR_FORMULA, |
| /* src-atop */ COEFF_FORMULA( kDA_GrBlendCoeff, kZero_GrBlendCoeff), |
| /* dst-atop */ COEFF_FORMULA( kIDA_GrBlendCoeff, kOne_GrBlendCoeff), |
| /* xor */ COEFF_FORMULA( kIDA_GrBlendCoeff, kZero_GrBlendCoeff), |
| /* plus */ COEFF_FORMULA( kOne_GrBlendCoeff, kOne_GrBlendCoeff), |
| /* modulate */ COEFF_FORMULA( kZero_GrBlendCoeff, kSC_GrBlendCoeff), |
| /* screen */ COEFF_FORMULA( kOne_GrBlendCoeff, kISC_GrBlendCoeff), |
| |
| }, /*>> Has coverage, input color opaque <<*/ { |
| |
| /* clear */ COVERAGE_SRC_COEFF_ZERO_FORMULA(BlendFormula::kCoverage_OutputType), |
| /* src */ COEFF_FORMULA( kOne_GrBlendCoeff, kISA_GrBlendCoeff), |
| /* dst */ NO_DST_WRITE_FORMULA, |
| /* src-over */ COEFF_FORMULA( kOne_GrBlendCoeff, kISA_GrBlendCoeff), |
| /* dst-over */ COEFF_FORMULA( kIDA_GrBlendCoeff, kOne_GrBlendCoeff), |
| /* src-in */ COEFF_FORMULA( kDA_GrBlendCoeff, kISA_GrBlendCoeff), |
| /* dst-in */ NO_DST_WRITE_FORMULA, |
| /* src-out */ COEFF_FORMULA( kIDA_GrBlendCoeff, kISA_GrBlendCoeff), |
| /* dst-out */ COVERAGE_SRC_COEFF_ZERO_FORMULA(BlendFormula::kCoverage_OutputType), |
| /* src-atop */ COEFF_FORMULA( kDA_GrBlendCoeff, kISA_GrBlendCoeff), |
| /* dst-atop */ COEFF_FORMULA( kIDA_GrBlendCoeff, kOne_GrBlendCoeff), |
| /* xor */ COEFF_FORMULA( kIDA_GrBlendCoeff, kISA_GrBlendCoeff), |
| /* plus */ COEFF_FORMULA( kOne_GrBlendCoeff, kOne_GrBlendCoeff), |
| /* modulate */ COVERAGE_SRC_COEFF_ZERO_FORMULA(BlendFormula::kISCModulate_OutputType), |
| /* screen */ COEFF_FORMULA( kOne_GrBlendCoeff, kISC_GrBlendCoeff), |
| }}}; |
| |
| static const BlendFormula gLCDBlendTable[(int)SkBlendMode::kLastCoeffMode + 1] = { |
| /* clear */ COVERAGE_SRC_COEFF_ZERO_FORMULA(BlendFormula::kCoverage_OutputType), |
| /* src */ COVERAGE_FORMULA(BlendFormula::kCoverage_OutputType, kOne_GrBlendCoeff), |
| /* dst */ NO_DST_WRITE_FORMULA, |
| /* src-over */ COVERAGE_FORMULA(BlendFormula::kSAModulate_OutputType, kOne_GrBlendCoeff), |
| /* dst-over */ COEFF_FORMULA( kIDA_GrBlendCoeff, kOne_GrBlendCoeff), |
| /* src-in */ COVERAGE_FORMULA(BlendFormula::kCoverage_OutputType, kDA_GrBlendCoeff), |
| /* dst-in */ COVERAGE_SRC_COEFF_ZERO_FORMULA(BlendFormula::kISAModulate_OutputType), |
| /* src-out */ COVERAGE_FORMULA(BlendFormula::kCoverage_OutputType, kIDA_GrBlendCoeff), |
| /* dst-out */ COEFF_FORMULA_SA_MODULATE( kZero_GrBlendCoeff, kISC_GrBlendCoeff), |
| /* src-atop */ COVERAGE_FORMULA(BlendFormula::kSAModulate_OutputType, kDA_GrBlendCoeff), |
| /* dst-atop */ COVERAGE_FORMULA(BlendFormula::kISAModulate_OutputType, kIDA_GrBlendCoeff), |
| /* xor */ COVERAGE_FORMULA(BlendFormula::kSAModulate_OutputType, kIDA_GrBlendCoeff), |
| /* plus */ COEFF_FORMULA( kOne_GrBlendCoeff, kOne_GrBlendCoeff), |
| /* modulate */ COVERAGE_SRC_COEFF_ZERO_FORMULA(BlendFormula::kISCModulate_OutputType), |
| /* screen */ COEFF_FORMULA( kOne_GrBlendCoeff, kISC_GrBlendCoeff), |
| }; |
| |
| static BlendFormula get_blend_formula(const GrProcOptInfo& colorPOI, |
| const GrProcOptInfo& coveragePOI, |
| bool hasMixedSamples, |
| SkBlendMode xfermode) { |
| SkASSERT((unsigned)xfermode <= (unsigned)SkBlendMode::kLastCoeffMode); |
| SkASSERT(!coveragePOI.isLCDCoverage()); |
| |
| bool conflatesCoverage = !coveragePOI.isSolidWhite() || hasMixedSamples; |
| return gBlendTable[colorPOI.isOpaque()][conflatesCoverage][(int)xfermode]; |
| } |
| |
| static BlendFormula get_lcd_blend_formula(const GrProcOptInfo& coveragePOI, |
| SkBlendMode xfermode) { |
| SkASSERT((unsigned)xfermode <= (unsigned)SkBlendMode::kLastCoeffMode); |
| SkASSERT(coveragePOI.isLCDCoverage()); |
| |
| return gLCDBlendTable[(int)xfermode]; |
| } |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| class PorterDuffXferProcessor : public GrXferProcessor { |
| public: |
| PorterDuffXferProcessor(BlendFormula blendFormula) : fBlendFormula(blendFormula) { |
| this->initClassID<PorterDuffXferProcessor>(); |
| } |
| |
| const char* name() const override { return "Porter Duff"; } |
| |
| GrGLSLXferProcessor* createGLSLInstance() const override; |
| |
| BlendFormula getBlendFormula() const { return fBlendFormula; } |
| |
| private: |
| GrXferProcessor::OptFlags onGetOptimizations(const GrPipelineAnalysis&, |
| bool doesStencilWrite, |
| GrColor* overrideColor, |
| const GrCaps&) const override; |
| |
| void onGetGLSLProcessorKey(const GrShaderCaps& caps, GrProcessorKeyBuilder* b) const override; |
| |
| bool onHasSecondaryOutput() const override { return fBlendFormula.hasSecondaryOutput(); } |
| |
| void onGetBlendInfo(GrXferProcessor::BlendInfo* blendInfo) const override { |
| blendInfo->fEquation = fBlendFormula.fBlendEquation; |
| blendInfo->fSrcBlend = fBlendFormula.fSrcCoeff; |
| blendInfo->fDstBlend = fBlendFormula.fDstCoeff; |
| blendInfo->fWriteColor = fBlendFormula.modifiesDst(); |
| } |
| |
| bool onIsEqual(const GrXferProcessor& xpBase) const override { |
| const PorterDuffXferProcessor& xp = xpBase.cast<PorterDuffXferProcessor>(); |
| return fBlendFormula == xp.fBlendFormula; |
| } |
| |
| const BlendFormula fBlendFormula; |
| |
| typedef GrXferProcessor INHERITED; |
| }; |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| static void append_color_output(const PorterDuffXferProcessor& xp, |
| GrGLSLXPFragmentBuilder* fragBuilder, |
| BlendFormula::OutputType outputType, const char* output, |
| const char* inColor, const char* inCoverage) { |
| SkASSERT(inCoverage); |
| SkASSERT(inColor); |
| switch (outputType) { |
| case BlendFormula::kNone_OutputType: |
| fragBuilder->codeAppendf("%s = vec4(0.0);", output); |
| break; |
| case BlendFormula::kCoverage_OutputType: |
| // We can have a coverage formula while not reading coverage if there are mixed samples. |
| fragBuilder->codeAppendf("%s = %s;", output, inCoverage); |
| break; |
| case BlendFormula::kModulate_OutputType: |
| fragBuilder->codeAppendf("%s = %s * %s;", output, inColor, inCoverage); |
| break; |
| case BlendFormula::kSAModulate_OutputType: |
| fragBuilder->codeAppendf("%s = %s.a * %s;", output, inColor, inCoverage); |
| break; |
| case BlendFormula::kISAModulate_OutputType: |
| fragBuilder->codeAppendf("%s = (1.0 - %s.a) * %s;", output, inColor, inCoverage); |
| break; |
| case BlendFormula::kISCModulate_OutputType: |
| fragBuilder->codeAppendf("%s = (vec4(1.0) - %s) * %s;", output, inColor, inCoverage); |
| break; |
| default: |
| SkFAIL("Unsupported output type."); |
| break; |
| } |
| } |
| |
| class GLPorterDuffXferProcessor : public GrGLSLXferProcessor { |
| public: |
| static void GenKey(const GrProcessor& processor, GrProcessorKeyBuilder* b) { |
| const PorterDuffXferProcessor& xp = processor.cast<PorterDuffXferProcessor>(); |
| b->add32(xp.getBlendFormula().fPrimaryOutputType | |
| (xp.getBlendFormula().fSecondaryOutputType << 3)); |
| GR_STATIC_ASSERT(BlendFormula::kLast_OutputType < 8); |
| } |
| |
| private: |
| void emitOutputsForBlendState(const EmitArgs& args) override { |
| const PorterDuffXferProcessor& xp = args.fXP.cast<PorterDuffXferProcessor>(); |
| GrGLSLXPFragmentBuilder* fragBuilder = args.fXPFragBuilder; |
| |
| BlendFormula blendFormula = xp.getBlendFormula(); |
| if (blendFormula.hasSecondaryOutput()) { |
| append_color_output(xp, fragBuilder, blendFormula.fSecondaryOutputType, |
| args.fOutputSecondary, args.fInputColor, args.fInputCoverage); |
| } |
| append_color_output(xp, fragBuilder, blendFormula.fPrimaryOutputType, |
| args.fOutputPrimary, args.fInputColor, args.fInputCoverage); |
| } |
| |
| void onSetData(const GrGLSLProgramDataManager&, const GrXferProcessor&) override {} |
| |
| typedef GrGLSLXferProcessor INHERITED; |
| }; |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| void PorterDuffXferProcessor::onGetGLSLProcessorKey(const GrShaderCaps&, |
| GrProcessorKeyBuilder* b) const { |
| GLPorterDuffXferProcessor::GenKey(*this, b); |
| } |
| |
| GrGLSLXferProcessor* PorterDuffXferProcessor::createGLSLInstance() const { |
| return new GLPorterDuffXferProcessor; |
| } |
| |
| GrXferProcessor::OptFlags PorterDuffXferProcessor::onGetOptimizations( |
| const GrPipelineAnalysis& analysis, |
| bool doesStencilWrite, |
| GrColor* overrideColor, |
| const GrCaps& caps) const { |
| GrXferProcessor::OptFlags optFlags = GrXferProcessor::kNone_OptFlags; |
| if (!fBlendFormula.modifiesDst()) { |
| if (!doesStencilWrite) { |
| optFlags |= GrXferProcessor::kSkipDraw_OptFlag; |
| } |
| optFlags |= (GrXferProcessor::kIgnoreColor_OptFlag | |
| GrXferProcessor::kCanTweakAlphaForCoverage_OptFlag); |
| } else { |
| if (!fBlendFormula.usesInputColor()) { |
| optFlags |= GrXferProcessor::kIgnoreColor_OptFlag; |
| } |
| if (analysis.fColorPOI.allStagesMultiplyInput() && |
| fBlendFormula.canTweakAlphaForCoverage() && !analysis.fCoveragePOI.isLCDCoverage()) { |
| optFlags |= GrXferProcessor::kCanTweakAlphaForCoverage_OptFlag; |
| } |
| } |
| return optFlags; |
| } |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| class ShaderPDXferProcessor : public GrXferProcessor { |
| public: |
| ShaderPDXferProcessor(const DstTexture* dstTexture, |
| bool hasMixedSamples, |
| SkBlendMode xfermode) |
| : INHERITED(dstTexture, true, hasMixedSamples) |
| , fXfermode(xfermode) { |
| this->initClassID<ShaderPDXferProcessor>(); |
| } |
| |
| const char* name() const override { return "Porter Duff Shader"; } |
| |
| GrGLSLXferProcessor* createGLSLInstance() const override; |
| |
| SkBlendMode getXfermode() const { return fXfermode; } |
| |
| private: |
| GrXferProcessor::OptFlags onGetOptimizations(const GrPipelineAnalysis&, bool, GrColor*, |
| const GrCaps&) const override { |
| return kNone_OptFlags; |
| } |
| |
| void onGetGLSLProcessorKey(const GrShaderCaps& caps, GrProcessorKeyBuilder* b) const override; |
| |
| bool onIsEqual(const GrXferProcessor& xpBase) const override { |
| const ShaderPDXferProcessor& xp = xpBase.cast<ShaderPDXferProcessor>(); |
| return fXfermode == xp.fXfermode; |
| } |
| |
| const SkBlendMode fXfermode; |
| |
| typedef GrXferProcessor INHERITED; |
| }; |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| class GLShaderPDXferProcessor : public GrGLSLXferProcessor { |
| public: |
| static void GenKey(const GrProcessor& processor, GrProcessorKeyBuilder* b) { |
| const ShaderPDXferProcessor& xp = processor.cast<ShaderPDXferProcessor>(); |
| b->add32((int)xp.getXfermode()); |
| } |
| |
| private: |
| void emitBlendCodeForDstRead(GrGLSLXPFragmentBuilder* fragBuilder, |
| GrGLSLUniformHandler* uniformHandler, |
| const char* srcColor, |
| const char* srcCoverage, |
| const char* dstColor, |
| const char* outColor, |
| const char* outColorSecondary, |
| const GrXferProcessor& proc) override { |
| const ShaderPDXferProcessor& xp = proc.cast<ShaderPDXferProcessor>(); |
| |
| GrGLSLBlend::AppendMode(fragBuilder, srcColor, dstColor, outColor, xp.getXfermode()); |
| |
| // Apply coverage. |
| INHERITED::DefaultCoverageModulation(fragBuilder, srcCoverage, dstColor, outColor, |
| outColorSecondary, xp); |
| } |
| |
| void onSetData(const GrGLSLProgramDataManager&, const GrXferProcessor&) override {} |
| |
| typedef GrGLSLXferProcessor INHERITED; |
| }; |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| void ShaderPDXferProcessor::onGetGLSLProcessorKey(const GrShaderCaps&, |
| GrProcessorKeyBuilder* b) const { |
| GLShaderPDXferProcessor::GenKey(*this, b); |
| } |
| |
| GrGLSLXferProcessor* ShaderPDXferProcessor::createGLSLInstance() const { |
| return new GLShaderPDXferProcessor; |
| } |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| class PDLCDXferProcessor : public GrXferProcessor { |
| public: |
| static GrXferProcessor* Create(SkBlendMode xfermode, const GrProcOptInfo& colorPOI); |
| |
| ~PDLCDXferProcessor() override; |
| |
| const char* name() const override { return "Porter Duff LCD"; } |
| |
| GrGLSLXferProcessor* createGLSLInstance() const override; |
| |
| private: |
| PDLCDXferProcessor(GrColor blendConstant, uint8_t alpha); |
| |
| GrXferProcessor::OptFlags onGetOptimizations(const GrPipelineAnalysis&, |
| bool doesStencilWrite, |
| GrColor* overrideColor, |
| const GrCaps&) const override; |
| |
| void onGetGLSLProcessorKey(const GrShaderCaps& caps, GrProcessorKeyBuilder* b) const override; |
| |
| void onGetBlendInfo(GrXferProcessor::BlendInfo* blendInfo) const override { |
| blendInfo->fSrcBlend = kConstC_GrBlendCoeff; |
| blendInfo->fDstBlend = kISC_GrBlendCoeff; |
| blendInfo->fBlendConstant = fBlendConstant; |
| } |
| |
| bool onIsEqual(const GrXferProcessor& xpBase) const override { |
| const PDLCDXferProcessor& xp = xpBase.cast<PDLCDXferProcessor>(); |
| if (fBlendConstant != xp.fBlendConstant || |
| fAlpha != xp.fAlpha) { |
| return false; |
| } |
| return true; |
| } |
| |
| GrColor fBlendConstant; |
| uint8_t fAlpha; |
| |
| typedef GrXferProcessor INHERITED; |
| }; |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| class GLPDLCDXferProcessor : public GrGLSLXferProcessor { |
| public: |
| GLPDLCDXferProcessor(const GrProcessor&) {} |
| |
| virtual ~GLPDLCDXferProcessor() {} |
| |
| static void GenKey(const GrProcessor& processor, const GrShaderCaps& caps, |
| GrProcessorKeyBuilder* b) {} |
| |
| private: |
| void emitOutputsForBlendState(const EmitArgs& args) override { |
| GrGLSLXPFragmentBuilder* fragBuilder = args.fXPFragBuilder; |
| SkASSERT(args.fInputCoverage); |
| fragBuilder->codeAppendf("%s = %s * %s;", args.fOutputPrimary, args.fInputColor, |
| args.fInputCoverage); |
| } |
| |
| void onSetData(const GrGLSLProgramDataManager&, const GrXferProcessor&) override {} |
| |
| typedef GrGLSLXferProcessor INHERITED; |
| }; |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| PDLCDXferProcessor::PDLCDXferProcessor(GrColor blendConstant, uint8_t alpha) |
| : fBlendConstant(blendConstant) |
| , fAlpha(alpha) { |
| this->initClassID<PDLCDXferProcessor>(); |
| } |
| |
| GrXferProcessor* PDLCDXferProcessor::Create(SkBlendMode xfermode, |
| const GrProcOptInfo& colorPOI) { |
| if (SkBlendMode::kSrcOver != xfermode) { |
| return nullptr; |
| } |
| |
| if (kRGBA_GrColorComponentFlags != colorPOI.validFlags()) { |
| return nullptr; |
| } |
| |
| GrColor blendConstant = GrUnpremulColor(colorPOI.color()); |
| uint8_t alpha = GrColorUnpackA(blendConstant); |
| blendConstant |= (0xff << GrColor_SHIFT_A); |
| |
| return new PDLCDXferProcessor(blendConstant, alpha); |
| } |
| |
| PDLCDXferProcessor::~PDLCDXferProcessor() { |
| } |
| |
| void PDLCDXferProcessor::onGetGLSLProcessorKey(const GrShaderCaps& caps, |
| GrProcessorKeyBuilder* b) const { |
| GLPDLCDXferProcessor::GenKey(*this, caps, b); |
| } |
| |
| GrGLSLXferProcessor* PDLCDXferProcessor::createGLSLInstance() const { |
| return new GLPDLCDXferProcessor(*this); |
| } |
| |
| GrXferProcessor::OptFlags PDLCDXferProcessor::onGetOptimizations(const GrPipelineAnalysis&, |
| bool doesStencilWrite, |
| GrColor* overrideColor, |
| const GrCaps& caps) const { |
| // We want to force our primary output to be alpha * Coverage, where alpha is the alpha |
| // value of the blend the constant. We should already have valid blend coeff's if we are at |
| // a point where we have RGB coverage. We don't need any color stages since the known color |
| // output is already baked into the blendConstant. |
| *overrideColor = GrColorPackRGBA(fAlpha, fAlpha, fAlpha, fAlpha); |
| return GrXferProcessor::kOverrideColor_OptFlag; |
| } |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| constexpr GrPorterDuffXPFactory::GrPorterDuffXPFactory(SkBlendMode xfermode) |
| : fBlendMode(xfermode) {} |
| |
| const GrXPFactory* GrPorterDuffXPFactory::Get(SkBlendMode blendMode) { |
| SkASSERT((unsigned)blendMode <= (unsigned)SkBlendMode::kLastCoeffMode); |
| |
| // If these objects are constructed as static constexpr by cl.exe (2015 SP2) the vtables are |
| // null. |
| #ifdef SK_BUILD_FOR_WIN |
| #define _CONSTEXPR_ |
| #else |
| #define _CONSTEXPR_ constexpr |
| #endif |
| static _CONSTEXPR_ const GrPorterDuffXPFactory gClearPDXPF(SkBlendMode::kClear); |
| static _CONSTEXPR_ const GrPorterDuffXPFactory gSrcPDXPF(SkBlendMode::kSrc); |
| static _CONSTEXPR_ const GrPorterDuffXPFactory gDstPDXPF(SkBlendMode::kDst); |
| static _CONSTEXPR_ const GrPorterDuffXPFactory gSrcOverPDXPF(SkBlendMode::kSrcOver); |
| static _CONSTEXPR_ const GrPorterDuffXPFactory gDstOverPDXPF(SkBlendMode::kDstOver); |
| static _CONSTEXPR_ const GrPorterDuffXPFactory gSrcInPDXPF(SkBlendMode::kSrcIn); |
| static _CONSTEXPR_ const GrPorterDuffXPFactory gDstInPDXPF(SkBlendMode::kDstIn); |
| static _CONSTEXPR_ const GrPorterDuffXPFactory gSrcOutPDXPF(SkBlendMode::kSrcOut); |
| static _CONSTEXPR_ const GrPorterDuffXPFactory gDstOutPDXPF(SkBlendMode::kDstOut); |
| static _CONSTEXPR_ const GrPorterDuffXPFactory gSrcATopPDXPF(SkBlendMode::kSrcATop); |
| static _CONSTEXPR_ const GrPorterDuffXPFactory gDstATopPDXPF(SkBlendMode::kDstATop); |
| static _CONSTEXPR_ const GrPorterDuffXPFactory gXorPDXPF(SkBlendMode::kXor); |
| static _CONSTEXPR_ const GrPorterDuffXPFactory gPlusPDXPF(SkBlendMode::kPlus); |
| static _CONSTEXPR_ const GrPorterDuffXPFactory gModulatePDXPF(SkBlendMode::kModulate); |
| static _CONSTEXPR_ const GrPorterDuffXPFactory gScreenPDXPF(SkBlendMode::kScreen); |
| #undef _CONSTEXPR_ |
| |
| switch (blendMode) { |
| case SkBlendMode::kClear: |
| return &gClearPDXPF; |
| case SkBlendMode::kSrc: |
| return &gSrcPDXPF; |
| case SkBlendMode::kDst: |
| return &gDstPDXPF; |
| case SkBlendMode::kSrcOver: |
| return &gSrcOverPDXPF; |
| case SkBlendMode::kDstOver: |
| return &gDstOverPDXPF; |
| case SkBlendMode::kSrcIn: |
| return &gSrcInPDXPF; |
| case SkBlendMode::kDstIn: |
| return &gDstInPDXPF; |
| case SkBlendMode::kSrcOut: |
| return &gSrcOutPDXPF; |
| case SkBlendMode::kDstOut: |
| return &gDstOutPDXPF; |
| case SkBlendMode::kSrcATop: |
| return &gSrcATopPDXPF; |
| case SkBlendMode::kDstATop: |
| return &gDstATopPDXPF; |
| case SkBlendMode::kXor: |
| return &gXorPDXPF; |
| case SkBlendMode::kPlus: |
| return &gPlusPDXPF; |
| case SkBlendMode::kModulate: |
| return &gModulatePDXPF; |
| case SkBlendMode::kScreen: |
| return &gScreenPDXPF; |
| default: |
| SkFAIL("Unexpected blend mode."); |
| return nullptr; |
| } |
| } |
| |
| GrXferProcessor* GrPorterDuffXPFactory::onCreateXferProcessor(const GrCaps& caps, |
| const GrPipelineAnalysis& analysis, |
| bool hasMixedSamples, |
| const DstTexture* dstTexture) const { |
| if (analysis.fUsesPLSDstRead) { |
| return new ShaderPDXferProcessor(dstTexture, hasMixedSamples, fBlendMode); |
| } |
| BlendFormula blendFormula; |
| if (analysis.fCoveragePOI.isLCDCoverage()) { |
| if (SkBlendMode::kSrcOver == fBlendMode && |
| kRGBA_GrColorComponentFlags == analysis.fColorPOI.validFlags() && |
| !caps.shaderCaps()->dualSourceBlendingSupport() && |
| !caps.shaderCaps()->dstReadInShaderSupport()) { |
| // If we don't have dual source blending or in shader dst reads, we fall back to this |
| // trick for rendering SrcOver LCD text instead of doing a dst copy. |
| SkASSERT(!dstTexture || !dstTexture->texture()); |
| return PDLCDXferProcessor::Create(fBlendMode, analysis.fColorPOI); |
| } |
| blendFormula = get_lcd_blend_formula(analysis.fCoveragePOI, fBlendMode); |
| } else { |
| blendFormula = get_blend_formula(analysis.fColorPOI, analysis.fCoveragePOI, hasMixedSamples, |
| fBlendMode); |
| } |
| |
| if (blendFormula.hasSecondaryOutput() && !caps.shaderCaps()->dualSourceBlendingSupport()) { |
| return new ShaderPDXferProcessor(dstTexture, hasMixedSamples, fBlendMode); |
| } |
| |
| SkASSERT(!dstTexture || !dstTexture->texture()); |
| return new PorterDuffXferProcessor(blendFormula); |
| } |
| |
| void GrPorterDuffXPFactory::getInvariantBlendedColor(const GrProcOptInfo& colorPOI, |
| InvariantBlendedColor* blendedColor) const { |
| // Find the blended color info based on the formula that does not have coverage. |
| BlendFormula colorFormula = gBlendTable[colorPOI.isOpaque()][0][(int)fBlendMode]; |
| if (colorFormula.usesDstColor()) { |
| blendedColor->fWillBlendWithDst = true; |
| blendedColor->fKnownColorFlags = kNone_GrColorComponentFlags; |
| return; |
| } |
| |
| blendedColor->fWillBlendWithDst = false; |
| |
| SkASSERT(kAdd_GrBlendEquation == colorFormula.fBlendEquation); |
| |
| switch (colorFormula.fSrcCoeff) { |
| case kZero_GrBlendCoeff: |
| blendedColor->fKnownColor = 0; |
| blendedColor->fKnownColorFlags = kRGBA_GrColorComponentFlags; |
| return; |
| |
| case kOne_GrBlendCoeff: |
| blendedColor->fKnownColor = colorPOI.color(); |
| blendedColor->fKnownColorFlags = colorPOI.validFlags(); |
| return; |
| |
| default: |
| blendedColor->fKnownColorFlags = kNone_GrColorComponentFlags; |
| return; |
| } |
| } |
| |
| bool GrPorterDuffXPFactory::onWillReadDstColor(const GrCaps& caps, |
| const GrPipelineAnalysis& analysis) const { |
| if (caps.shaderCaps()->dualSourceBlendingSupport()) { |
| return false; |
| } |
| |
| // When we have four channel coverage we always need to read the dst in order to correctly |
| // blend. The one exception is when we are using srcover mode and we know the input color into |
| // the XP. |
| if (analysis.fCoveragePOI.isLCDCoverage()) { |
| if (SkBlendMode::kSrcOver == fBlendMode && |
| kRGBA_GrColorComponentFlags == analysis.fColorPOI.validFlags() && |
| !caps.shaderCaps()->dstReadInShaderSupport()) { |
| return false; |
| } |
| return get_lcd_blend_formula(analysis.fCoveragePOI, fBlendMode).hasSecondaryOutput(); |
| } |
| |
| // We fallback on the shader XP when the blend formula would use dual source blending but we |
| // don't have support for it. |
| static const bool kHasMixedSamples = false; |
| SkASSERT(!caps.usesMixedSamples()); // We never use mixed samples without dual source blending. |
| auto formula = get_blend_formula(analysis.fColorPOI, analysis.fCoveragePOI, kHasMixedSamples, |
| fBlendMode); |
| return formula.hasSecondaryOutput(); |
| } |
| |
| GR_DEFINE_XP_FACTORY_TEST(GrPorterDuffXPFactory); |
| |
| const GrXPFactory* GrPorterDuffXPFactory::TestGet(GrProcessorTestData* d) { |
| SkBlendMode mode = SkBlendMode(d->fRandom->nextULessThan((int)SkBlendMode::kLastCoeffMode)); |
| return GrPorterDuffXPFactory::Get(mode); |
| } |
| |
| void GrPorterDuffXPFactory::TestGetXPOutputTypes(const GrXferProcessor* xp, |
| int* outPrimary, |
| int* outSecondary) { |
| if (!!strcmp(xp->name(), "Porter Duff")) { |
| *outPrimary = *outSecondary = -1; |
| return; |
| } |
| BlendFormula blendFormula = static_cast<const PorterDuffXferProcessor*>(xp)->getBlendFormula(); |
| *outPrimary = blendFormula.fPrimaryOutputType; |
| *outSecondary = blendFormula.fSecondaryOutputType; |
| } |
| |
| |
| //////////////////////////////////////////////////////////////////////////////////////////////// |
| // SrcOver Global functions |
| //////////////////////////////////////////////////////////////////////////////////////////////// |
| const GrXferProcessor& GrPorterDuffXPFactory::SimpleSrcOverXP() { |
| static BlendFormula gSrcOverBlendFormula = COEFF_FORMULA(kOne_GrBlendCoeff, |
| kISA_GrBlendCoeff); |
| static PorterDuffXferProcessor gSrcOverXP(gSrcOverBlendFormula); |
| return gSrcOverXP; |
| } |
| |
| GrXferProcessor* GrPorterDuffXPFactory::CreateSrcOverXferProcessor( |
| const GrCaps& caps, |
| const GrPipelineAnalysis& analysis, |
| bool hasMixedSamples, |
| const GrXferProcessor::DstTexture* dstTexture) { |
| if (analysis.fUsesPLSDstRead) { |
| return new ShaderPDXferProcessor(dstTexture, hasMixedSamples, SkBlendMode::kSrcOver); |
| } |
| |
| // We want to not make an xfer processor if possible. Thus for the simple case where we are not |
| // doing lcd blending we will just use our global SimpleSrcOverXP. This slightly differs from |
| // the general case where we convert a src-over blend that has solid coverage and an opaque |
| // color to src-mode, which allows disabling of blending. |
| if (!analysis.fCoveragePOI.isLCDCoverage()) { |
| // We return nullptr here, which our caller interprets as meaning "use SimpleSrcOverXP". |
| // We don't simply return the address of that XP here because our caller would have to unref |
| // it and since it is a global object and GrProgramElement's ref-cnting system is not thread |
| // safe. |
| return nullptr; |
| } |
| |
| if (kRGBA_GrColorComponentFlags == analysis.fColorPOI.validFlags() && |
| !caps.shaderCaps()->dualSourceBlendingSupport() && |
| !caps.shaderCaps()->dstReadInShaderSupport()) { |
| // If we don't have dual source blending or in shader dst reads, we fall |
| // back to this trick for rendering SrcOver LCD text instead of doing a |
| // dst copy. |
| SkASSERT(!dstTexture || !dstTexture->texture()); |
| return PDLCDXferProcessor::Create(SkBlendMode::kSrcOver, analysis.fColorPOI); |
| } |
| |
| BlendFormula blendFormula; |
| blendFormula = get_lcd_blend_formula(analysis.fCoveragePOI, SkBlendMode::kSrcOver); |
| if (blendFormula.hasSecondaryOutput() && !caps.shaderCaps()->dualSourceBlendingSupport()) { |
| return new ShaderPDXferProcessor(dstTexture, hasMixedSamples, SkBlendMode::kSrcOver); |
| } |
| |
| SkASSERT(!dstTexture || !dstTexture->texture()); |
| return new PorterDuffXferProcessor(blendFormula); |
| } |
| |
| bool GrPorterDuffXPFactory::SrcOverWillNeedDstTexture(const GrCaps& caps, |
| const GrPipelineAnalysis& analysis) { |
| if (caps.shaderCaps()->dstReadInShaderSupport() || |
| caps.shaderCaps()->dualSourceBlendingSupport()) { |
| return false; |
| } |
| |
| // When we have four channel coverage we always need to read the dst in order to correctly |
| // blend. The one exception is when we are using srcover mode and we know the input color |
| // into the XP. |
| if (analysis.fCoveragePOI.isLCDCoverage()) { |
| if (kRGBA_GrColorComponentFlags == analysis.fColorPOI.validFlags() && |
| !caps.shaderCaps()->dstReadInShaderSupport()) { |
| return false; |
| } |
| auto formula = get_lcd_blend_formula(analysis.fCoveragePOI, SkBlendMode::kSrcOver); |
| return formula.hasSecondaryOutput(); |
| } |
| |
| // We fallback on the shader XP when the blend formula would use dual source blending but we |
| // don't have support for it. |
| static const bool kHasMixedSamples = false; |
| SkASSERT(!caps.usesMixedSamples()); // We never use mixed samples without dual source blending. |
| auto formula = get_blend_formula(analysis.fColorPOI, analysis.fCoveragePOI, kHasMixedSamples, |
| SkBlendMode::kSrcOver); |
| return formula.hasSecondaryOutput(); |
| } |
