| /* |
| * 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 "GrRODrawState.h" |
| |
| #include "GrDrawTargetCaps.h" |
| #include "GrRenderTarget.h" |
| |
| //////////////////////////////////////////////////////////////////////////////// |
| |
| GrRODrawState::GrRODrawState(const GrRODrawState& drawState) : INHERITED() { |
| fRenderTarget.setResource(SkSafeRef(drawState.fRenderTarget.getResource()), |
| GrIORef::kWrite_IOType); |
| } |
| |
| bool GrRODrawState::isEqual(const GrRODrawState& that) const { |
| bool usingVertexColors = this->hasColorVertexAttribute(); |
| if (!usingVertexColors && this->fColor != that.fColor) { |
| return false; |
| } |
| |
| if (this->getRenderTarget() != that.getRenderTarget() || |
| this->fColorStages.count() != that.fColorStages.count() || |
| this->fCoverageStages.count() != that.fCoverageStages.count() || |
| !this->fViewMatrix.cheapEqualTo(that.fViewMatrix) || |
| this->fSrcBlend != that.fSrcBlend || |
| this->fDstBlend != that.fDstBlend || |
| this->fBlendConstant != that.fBlendConstant || |
| this->fFlagBits != that.fFlagBits || |
| this->fVACount != that.fVACount || |
| this->fVAStride != that.fVAStride || |
| memcmp(this->fVAPtr, that.fVAPtr, this->fVACount * sizeof(GrVertexAttrib)) || |
| this->fStencilSettings != that.fStencilSettings || |
| this->fDrawFace != that.fDrawFace) { |
| return false; |
| } |
| |
| bool usingVertexCoverage = this->hasCoverageVertexAttribute(); |
| if (!usingVertexCoverage && this->fCoverage != that.fCoverage) { |
| return false; |
| } |
| |
| bool explicitLocalCoords = this->hasLocalCoordAttribute(); |
| if (this->hasGeometryProcessor()) { |
| if (!that.hasGeometryProcessor()) { |
| return false; |
| } else if (!GrProcessorStage::AreCompatible(*this->getGeometryProcessor(), |
| *that.getGeometryProcessor(), |
| explicitLocalCoords)) { |
| return false; |
| } |
| } else if (that.hasGeometryProcessor()) { |
| return false; |
| } |
| |
| for (int i = 0; i < this->numColorStages(); i++) { |
| if (!GrProcessorStage::AreCompatible(this->getColorStage(i), that.getColorStage(i), |
| explicitLocalCoords)) { |
| return false; |
| } |
| } |
| for (int i = 0; i < this->numCoverageStages(); i++) { |
| if (!GrProcessorStage::AreCompatible(this->getCoverageStage(i), that.getCoverageStage(i), |
| explicitLocalCoords)) { |
| return false; |
| } |
| } |
| |
| SkASSERT(0 == memcmp(this->fFixedFunctionVertexAttribIndices, |
| that.fFixedFunctionVertexAttribIndices, |
| sizeof(this->fFixedFunctionVertexAttribIndices))); |
| |
| return true; |
| } |
| |
| //////////////////////////////////////////////////////////////////////////////// |
| |
| bool GrRODrawState::validateVertexAttribs() const { |
| // check consistency of effects and attributes |
| GrSLType slTypes[kMaxVertexAttribCnt]; |
| for (int i = 0; i < kMaxVertexAttribCnt; ++i) { |
| slTypes[i] = static_cast<GrSLType>(-1); |
| } |
| |
| if (this->hasGeometryProcessor()) { |
| const GrGeometryStage& stage = *this->getGeometryProcessor(); |
| const GrGeometryProcessor* gp = stage.getGeometryProcessor(); |
| SkASSERT(gp); |
| // make sure that any attribute indices have the correct binding type, that the attrib |
| // type and effect's shader lang type are compatible, and that attributes shared by |
| // multiple effects use the same shader lang type. |
| const GrGeometryProcessor::VertexAttribArray& s = gp->getVertexAttribs(); |
| |
| int effectIndex = 0; |
| for (int index = 0; index < fVACount; index++) { |
| if (kGeometryProcessor_GrVertexAttribBinding != fVAPtr[index].fBinding) { |
| // we only care about effect bindings |
| continue; |
| } |
| SkASSERT(effectIndex < s.count()); |
| GrSLType effectSLType = s[effectIndex].getType(); |
| GrVertexAttribType attribType = fVAPtr[index].fType; |
| int slVecCount = GrSLTypeVectorCount(effectSLType); |
| int attribVecCount = GrVertexAttribTypeVectorCount(attribType); |
| if (slVecCount != attribVecCount || |
| (static_cast<GrSLType>(-1) != slTypes[index] && slTypes[index] != effectSLType)) { |
| return false; |
| } |
| slTypes[index] = effectSLType; |
| effectIndex++; |
| } |
| // Make sure all attributes are consumed and we were able to find everything |
| SkASSERT(s.count() == effectIndex); |
| } |
| |
| return true; |
| } |
| |
| bool GrRODrawState::hasSolidCoverage() const { |
| // If we're drawing coverage directly then coverage is effectively treated as color. |
| if (this->isCoverageDrawing()) { |
| return true; |
| } |
| |
| GrColor coverage; |
| uint32_t validComponentFlags; |
| // Initialize to an unknown starting coverage if per-vertex coverage is specified. |
| if (this->hasCoverageVertexAttribute()) { |
| validComponentFlags = 0; |
| } else { |
| coverage = fCoverage; |
| validComponentFlags = kRGBA_GrColorComponentFlags; |
| } |
| |
| // Run through the coverage stages and see if the coverage will be all ones at the end. |
| if (this->hasGeometryProcessor()) { |
| const GrGeometryProcessor* gp = fGeometryProcessor->getGeometryProcessor(); |
| gp->getConstantColorComponents(&coverage, &validComponentFlags); |
| } |
| for (int s = 0; s < this->numCoverageStages(); ++s) { |
| const GrProcessor* processor = this->getCoverageStage(s).getProcessor(); |
| processor->getConstantColorComponents(&coverage, &validComponentFlags); |
| } |
| return (kRGBA_GrColorComponentFlags == validComponentFlags) && (0xffffffff == coverage); |
| } |
| |
| //////////////////////////////////////////////////////////////////////////////// |
| |
| bool GrRODrawState::willEffectReadDstColor() const { |
| if (!this->isColorWriteDisabled()) { |
| for (int s = 0; s < this->numColorStages(); ++s) { |
| if (this->getColorStage(s).getFragmentProcessor()->willReadDstColor()) { |
| return true; |
| } |
| } |
| } |
| for (int s = 0; s < this->numCoverageStages(); ++s) { |
| if (this->getCoverageStage(s).getFragmentProcessor()->willReadDstColor()) { |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| //////////////////////////////////////////////////////////////////////////////// |
| |
| GrRODrawState::BlendOptFlags GrRODrawState::getBlendOpts(bool forceCoverage, |
| GrBlendCoeff* srcCoeff, |
| GrBlendCoeff* dstCoeff) const { |
| GrBlendCoeff bogusSrcCoeff, bogusDstCoeff; |
| if (NULL == srcCoeff) { |
| srcCoeff = &bogusSrcCoeff; |
| } |
| if (NULL == dstCoeff) { |
| dstCoeff = &bogusDstCoeff; |
| } |
| |
| *srcCoeff = this->getSrcBlendCoeff(); |
| *dstCoeff = this->getDstBlendCoeff(); |
| |
| if (this->isColorWriteDisabled()) { |
| *srcCoeff = kZero_GrBlendCoeff; |
| *dstCoeff = kOne_GrBlendCoeff; |
| } |
| |
| bool srcAIsOne = this->srcAlphaWillBeOne(); |
| bool dstCoeffIsOne = kOne_GrBlendCoeff == *dstCoeff || |
| (kSA_GrBlendCoeff == *dstCoeff && srcAIsOne); |
| bool dstCoeffIsZero = kZero_GrBlendCoeff == *dstCoeff || |
| (kISA_GrBlendCoeff == *dstCoeff && srcAIsOne); |
| |
| // When coeffs are (0,1) there is no reason to draw at all, unless |
| // stenciling is enabled. Having color writes disabled is effectively |
| // (0,1). |
| if ((kZero_GrBlendCoeff == *srcCoeff && dstCoeffIsOne)) { |
| if (this->getStencil().doesWrite()) { |
| return kEmitCoverage_BlendOptFlag; |
| } else { |
| *dstCoeff = kOne_GrBlendCoeff; |
| return kSkipDraw_BlendOptFlag; |
| } |
| } |
| |
| bool hasCoverage = forceCoverage || !this->hasSolidCoverage(); |
| |
| // if we don't have coverage we can check whether the dst |
| // has to read at all. If not, we'll disable blending. |
| if (!hasCoverage) { |
| if (dstCoeffIsZero) { |
| if (kOne_GrBlendCoeff == *srcCoeff) { |
| // if there is no coverage and coeffs are (1,0) then we |
| // won't need to read the dst at all, it gets replaced by src |
| *dstCoeff = kZero_GrBlendCoeff; |
| return kNone_BlendOpt; |
| } else if (kZero_GrBlendCoeff == *srcCoeff) { |
| // if the op is "clear" then we don't need to emit a color |
| // or blend, just write transparent black into the dst. |
| *srcCoeff = kOne_GrBlendCoeff; |
| *dstCoeff = kZero_GrBlendCoeff; |
| return kEmitTransBlack_BlendOptFlag; |
| } |
| } |
| } else if (this->isCoverageDrawing()) { |
| // we have coverage but we aren't distinguishing it from alpha by request. |
| return kCoverageAsAlpha_BlendOptFlag; |
| } else { |
| // check whether coverage can be safely rolled into alpha |
| // of if we can skip color computation and just emit coverage |
| if (this->canTweakAlphaForCoverage()) { |
| return kCoverageAsAlpha_BlendOptFlag; |
| } |
| if (dstCoeffIsZero) { |
| if (kZero_GrBlendCoeff == *srcCoeff) { |
| // the source color is not included in the blend |
| // the dst coeff is effectively zero so blend works out to: |
| // (c)(0)D + (1-c)D = (1-c)D. |
| *dstCoeff = kISA_GrBlendCoeff; |
| return kEmitCoverage_BlendOptFlag; |
| } else if (srcAIsOne) { |
| // the dst coeff is effectively zero so blend works out to: |
| // cS + (c)(0)D + (1-c)D = cS + (1-c)D. |
| // If Sa is 1 then we can replace Sa with c |
| // and set dst coeff to 1-Sa. |
| *dstCoeff = kISA_GrBlendCoeff; |
| return kCoverageAsAlpha_BlendOptFlag; |
| } |
| } else if (dstCoeffIsOne) { |
| // the dst coeff is effectively one so blend works out to: |
| // cS + (c)(1)D + (1-c)D = cS + D. |
| *dstCoeff = kOne_GrBlendCoeff; |
| return kCoverageAsAlpha_BlendOptFlag; |
| } |
| } |
| |
| return kNone_BlendOpt; |
| } |
| |
| //////////////////////////////////////////////////////////////////////////////// |
| |
| // Some blend modes allow folding a fractional coverage value into the color's alpha channel, while |
| // others will blend incorrectly. |
| bool GrRODrawState::canTweakAlphaForCoverage() const { |
| /* |
| The fractional coverage is f. |
| The src and dst coeffs are Cs and Cd. |
| The dst and src colors are S and D. |
| We want the blend to compute: f*Cs*S + (f*Cd + (1-f))D. By tweaking the source color's alpha |
| we're replacing S with S'=fS. It's obvious that that first term will always be ok. The second |
| term can be rearranged as [1-(1-Cd)f]D. By substituting in the various possibilities for Cd we |
| find that only 1, ISA, and ISC produce the correct destination when applied to S' and D. |
| Also, if we're directly rendering coverage (isCoverageDrawing) then coverage is treated as |
| color by definition. |
| */ |
| return kOne_GrBlendCoeff == fDstBlend || |
| kISA_GrBlendCoeff == fDstBlend || |
| kISC_GrBlendCoeff == fDstBlend || |
| this->isCoverageDrawing(); |
| } |
| |
| void GrRODrawState::convertToPendingExec() { |
| fRenderTarget.markPendingIO(); |
| fRenderTarget.removeRef(); |
| for (int i = 0; i < fColorStages.count(); ++i) { |
| fColorStages[i].convertToPendingExec(); |
| } |
| if (fGeometryProcessor) { |
| fGeometryProcessor->convertToPendingExec(); |
| } |
| for (int i = 0; i < fCoverageStages.count(); ++i) { |
| fCoverageStages[i].convertToPendingExec(); |
| } |
| } |
| |
| bool GrRODrawState::srcAlphaWillBeOne() const { |
| uint32_t validComponentFlags; |
| GrColor color; |
| // Check if per-vertex or constant color may have partial alpha |
| if (this->hasColorVertexAttribute()) { |
| if (fHints & kVertexColorsAreOpaque_Hint) { |
| validComponentFlags = kA_GrColorComponentFlag; |
| color = 0xFF << GrColor_SHIFT_A; |
| } else { |
| validComponentFlags = 0; |
| color = 0; // not strictly necessary but we get false alarms from tools about uninit. |
| } |
| } else { |
| validComponentFlags = kRGBA_GrColorComponentFlags; |
| color = this->getColor(); |
| } |
| |
| // Run through the color stages |
| for (int s = 0; s < this->numColorStages(); ++s) { |
| const GrProcessor* processor = this->getColorStage(s).getProcessor(); |
| processor->getConstantColorComponents(&color, &validComponentFlags); |
| } |
| |
| // Check whether coverage is treated as color. If so we run through the coverage computation. |
| if (this->isCoverageDrawing()) { |
| // The shader generated for coverage drawing runs the full coverage computation and then |
| // makes the shader output be the multiplication of color and coverage. We mirror that here. |
| GrColor coverage; |
| uint32_t coverageComponentFlags; |
| if (this->hasCoverageVertexAttribute()) { |
| coverageComponentFlags = 0; |
| coverage = 0; // suppresses any warnings. |
| } else { |
| coverageComponentFlags = kRGBA_GrColorComponentFlags; |
| coverage = this->getCoverageColor(); |
| } |
| |
| // Run through the coverage stages |
| for (int s = 0; s < this->numCoverageStages(); ++s) { |
| const GrProcessor* processor = this->getCoverageStage(s).getProcessor(); |
| processor->getConstantColorComponents(&coverage, &coverageComponentFlags); |
| } |
| |
| // Since the shader will multiply coverage and color, the only way the final A==1 is if |
| // coverage and color both have A==1. |
| return (kA_GrColorComponentFlag & validComponentFlags & coverageComponentFlags) && |
| 0xFF == GrColorUnpackA(color) && 0xFF == GrColorUnpackA(coverage); |
| |
| } |
| |
| return (kA_GrColorComponentFlag & validComponentFlags) && 0xFF == GrColorUnpackA(color); |
| } |
| |
