| /* |
| * Copyright 2012 Google Inc. |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #include "GrDrawState.h" |
| |
| #include "GrBlend.h" |
| #include "GrOptDrawState.h" |
| #include "GrPaint.h" |
| #include "GrProcOptInfo.h" |
| |
| //////////////////////////////////////////////////////////////////////////////s |
| |
| bool GrDrawState::isEqual(const GrDrawState& 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 (!this->getGeometryProcessor()->isEqual(*that.getGeometryProcessor())) { |
| return false; |
| } |
| } else if (that.hasGeometryProcessor()) { |
| return false; |
| } |
| |
| for (int i = 0; i < this->numColorStages(); i++) { |
| if (!GrFragmentStage::AreCompatible(this->getColorStage(i), that.getColorStage(i), |
| explicitLocalCoords)) { |
| return false; |
| } |
| } |
| for (int i = 0; i < this->numCoverageStages(); i++) { |
| if (!GrFragmentStage::AreCompatible(this->getCoverageStage(i), that.getCoverageStage(i), |
| explicitLocalCoords)) { |
| return false; |
| } |
| } |
| |
| SkASSERT(0 == memcmp(this->fFixedFunctionVertexAttribIndices, |
| that.fFixedFunctionVertexAttribIndices, |
| sizeof(this->fFixedFunctionVertexAttribIndices))); |
| |
| return true; |
| } |
| |
| //////////////////////////////////////////////////////////////////////////////s |
| |
| GrDrawState::GrDrawState(const GrDrawState& state, const SkMatrix& preConcatMatrix) { |
| SkDEBUGCODE(fBlockEffectRemovalCnt = 0;) |
| *this = state; |
| if (!preConcatMatrix.isIdentity()) { |
| for (int i = 0; i < this->numColorStages(); ++i) { |
| fColorStages[i].localCoordChange(preConcatMatrix); |
| } |
| for (int i = 0; i < this->numCoverageStages(); ++i) { |
| fCoverageStages[i].localCoordChange(preConcatMatrix); |
| } |
| } |
| } |
| |
| GrDrawState& GrDrawState::operator=(const GrDrawState& that) { |
| fRenderTarget.reset(SkSafeRef(that.fRenderTarget.get())); |
| fColor = that.fColor; |
| fViewMatrix = that.fViewMatrix; |
| fSrcBlend = that.fSrcBlend; |
| fDstBlend = that.fDstBlend; |
| fBlendConstant = that.fBlendConstant; |
| fFlagBits = that.fFlagBits; |
| fVACount = that.fVACount; |
| fVAPtr = that.fVAPtr; |
| fVAStride = that.fVAStride; |
| fStencilSettings = that.fStencilSettings; |
| fCoverage = that.fCoverage; |
| fDrawFace = that.fDrawFace; |
| fGeometryProcessor.reset(SkSafeRef(that.fGeometryProcessor.get())); |
| fColorStages = that.fColorStages; |
| fCoverageStages = that.fCoverageStages; |
| |
| fHints = that.fHints; |
| |
| fColorProcInfoValid = that.fColorProcInfoValid; |
| fCoverageProcInfoValid = that.fCoverageProcInfoValid; |
| if (fColorProcInfoValid) { |
| fColorProcInfo = that.fColorProcInfo; |
| } |
| if (fCoverageProcInfoValid) { |
| fCoverageProcInfo = that.fCoverageProcInfo; |
| } |
| |
| memcpy(fFixedFunctionVertexAttribIndices, |
| that.fFixedFunctionVertexAttribIndices, |
| sizeof(fFixedFunctionVertexAttribIndices)); |
| return *this; |
| } |
| |
| void GrDrawState::onReset(const SkMatrix* initialViewMatrix) { |
| SkASSERT(0 == fBlockEffectRemovalCnt || 0 == this->numTotalStages()); |
| fRenderTarget.reset(NULL); |
| |
| fGeometryProcessor.reset(NULL); |
| fColorStages.reset(); |
| fCoverageStages.reset(); |
| |
| |
| this->setDefaultVertexAttribs(); |
| |
| fColor = 0xffffffff; |
| if (NULL == initialViewMatrix) { |
| fViewMatrix.reset(); |
| } else { |
| fViewMatrix = *initialViewMatrix; |
| } |
| fSrcBlend = kOne_GrBlendCoeff; |
| fDstBlend = kZero_GrBlendCoeff; |
| fBlendConstant = 0x0; |
| fFlagBits = 0x0; |
| fStencilSettings.setDisabled(); |
| fCoverage = 0xff; |
| fDrawFace = kBoth_DrawFace; |
| |
| fHints = 0; |
| |
| fColorProcInfoValid = false; |
| fCoverageProcInfoValid = false; |
| } |
| |
| bool GrDrawState::setIdentityViewMatrix() { |
| if (this->numFragmentStages()) { |
| SkMatrix invVM; |
| if (!fViewMatrix.invert(&invVM)) { |
| // sad trombone sound |
| return false; |
| } |
| for (int s = 0; s < this->numColorStages(); ++s) { |
| fColorStages[s].localCoordChange(invVM); |
| } |
| for (int s = 0; s < this->numCoverageStages(); ++s) { |
| fCoverageStages[s].localCoordChange(invVM); |
| } |
| } |
| fViewMatrix.reset(); |
| return true; |
| } |
| |
| void GrDrawState::setFromPaint(const GrPaint& paint, const SkMatrix& vm, GrRenderTarget* rt) { |
| SkASSERT(0 == fBlockEffectRemovalCnt || 0 == this->numTotalStages()); |
| |
| fGeometryProcessor.reset(NULL); |
| fColorStages.reset(); |
| fCoverageStages.reset(); |
| |
| for (int i = 0; i < paint.numColorStages(); ++i) { |
| fColorStages.push_back(paint.getColorStage(i)); |
| } |
| |
| for (int i = 0; i < paint.numCoverageStages(); ++i) { |
| fCoverageStages.push_back(paint.getCoverageStage(i)); |
| } |
| |
| this->setRenderTarget(rt); |
| |
| fViewMatrix = vm; |
| |
| // These have no equivalent in GrPaint, set them to defaults |
| fBlendConstant = 0x0; |
| fDrawFace = kBoth_DrawFace; |
| fStencilSettings.setDisabled(); |
| fFlagBits = 0; |
| fHints = 0; |
| |
| // Enable the clip bit |
| this->enableState(GrDrawState::kClip_StateBit); |
| |
| this->setColor(paint.getColor()); |
| this->setState(GrDrawState::kDither_StateBit, paint.isDither()); |
| this->setState(GrDrawState::kHWAntialias_StateBit, paint.isAntiAlias()); |
| |
| this->setBlendFunc(paint.getSrcBlendCoeff(), paint.getDstBlendCoeff()); |
| this->setCoverage(0xFF); |
| fColorProcInfoValid = false; |
| fCoverageProcInfoValid = false; |
| } |
| |
| //////////////////////////////////////////////////////////////////////////////// |
| |
| bool GrDrawState::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 GrGeometryProcessor* gp = this->getGeometryProcessor(); |
| // 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; |
| } |
| |
| //////////////////////////////////////////////////////////////////////////////// |
| |
| static void validate_vertex_attribs(const GrVertexAttrib* attribs, int count, size_t stride) { |
| // this works as long as we're 4 byte-aligned |
| #ifdef SK_DEBUG |
| uint32_t overlapCheck = 0; |
| SkASSERT(count <= GrDrawState::kMaxVertexAttribCnt); |
| for (int index = 0; index < count; ++index) { |
| size_t attribSize = GrVertexAttribTypeSize(attribs[index].fType); |
| size_t attribOffset = attribs[index].fOffset; |
| SkASSERT(attribOffset + attribSize <= stride); |
| size_t dwordCount = attribSize >> 2; |
| uint32_t mask = (1 << dwordCount)-1; |
| size_t offsetShift = attribOffset >> 2; |
| SkASSERT(!(overlapCheck & (mask << offsetShift))); |
| overlapCheck |= (mask << offsetShift); |
| } |
| #endif |
| } |
| |
| //////////////////////////////////////////////////////////////////////////////// |
| |
| void GrDrawState::internalSetVertexAttribs(const GrVertexAttrib* attribs, int count, |
| size_t stride) { |
| SkASSERT(count <= kMaxVertexAttribCnt); |
| |
| fVAPtr = attribs; |
| fVACount = count; |
| fVAStride = stride; |
| validate_vertex_attribs(fVAPtr, fVACount, fVAStride); |
| |
| // Set all the indices to -1 |
| memset(fFixedFunctionVertexAttribIndices, |
| 0xff, |
| sizeof(fFixedFunctionVertexAttribIndices)); |
| #ifdef SK_DEBUG |
| uint32_t overlapCheck = 0; |
| #endif |
| for (int i = 0; i < count; ++i) { |
| if (attribs[i].fBinding < kGrFixedFunctionVertexAttribBindingCnt) { |
| // The fixed function attribs can only be specified once |
| SkASSERT(-1 == fFixedFunctionVertexAttribIndices[attribs[i].fBinding]); |
| SkASSERT(GrFixedFunctionVertexAttribVectorCount(attribs[i].fBinding) == |
| GrVertexAttribTypeVectorCount(attribs[i].fType)); |
| fFixedFunctionVertexAttribIndices[attribs[i].fBinding] = i; |
| } |
| #ifdef SK_DEBUG |
| size_t dwordCount = GrVertexAttribTypeSize(attribs[i].fType) >> 2; |
| uint32_t mask = (1 << dwordCount)-1; |
| size_t offsetShift = attribs[i].fOffset >> 2; |
| SkASSERT(!(overlapCheck & (mask << offsetShift))); |
| overlapCheck |= (mask << offsetShift); |
| #endif |
| } |
| fColorProcInfoValid = false; |
| fCoverageProcInfoValid = false; |
| // Positions must be specified. |
| SkASSERT(-1 != fFixedFunctionVertexAttribIndices[kPosition_GrVertexAttribBinding]); |
| } |
| |
| //////////////////////////////////////////////////////////////////////////////// |
| |
| void GrDrawState::setDefaultVertexAttribs() { |
| static const GrVertexAttrib kPositionAttrib = |
| {kVec2f_GrVertexAttribType, 0, kPosition_GrVertexAttribBinding}; |
| |
| fVAPtr = &kPositionAttrib; |
| fVACount = 1; |
| fVAStride = GrVertexAttribTypeSize(kVec2f_GrVertexAttribType); |
| |
| // set all the fixed function indices to -1 except position. |
| memset(fFixedFunctionVertexAttribIndices, |
| 0xff, |
| sizeof(fFixedFunctionVertexAttribIndices)); |
| fFixedFunctionVertexAttribIndices[kPosition_GrVertexAttribBinding] = 0; |
| fColorProcInfoValid = false; |
| fCoverageProcInfoValid = false; |
| } |
| |
| //////////////////////////////////////////////////////////////////////////////// |
| |
| bool GrDrawState::couldApplyCoverage(const GrDrawTargetCaps& caps) const { |
| if (caps.dualSourceBlendingSupport()) { |
| return true; |
| } |
| // we can correctly apply coverage if a) we have dual source blending |
| // or b) one of our blend optimizations applies |
| // or c) the src, dst blend coeffs are 1,0 and we will read Dst Color |
| GrBlendCoeff srcCoeff; |
| GrBlendCoeff dstCoeff; |
| BlendOpt opt = this->getBlendOpt(true, &srcCoeff, &dstCoeff); |
| return GrDrawState::kNone_BlendOpt != opt || |
| (this->willEffectReadDstColor() && |
| kOne_GrBlendCoeff == srcCoeff && kZero_GrBlendCoeff == dstCoeff); |
| } |
| |
| bool GrDrawState::hasSolidCoverage() const { |
| // If we're drawing coverage directly then coverage is effectively treated as color. |
| if (this->isCoverageDrawing()) { |
| return true; |
| } |
| |
| if (this->numCoverageStages() > 0) { |
| return false; |
| } |
| |
| this->calcCoverageInvariantOutput(); |
| return fCoverageProcInfo.isSolidWhite(); |
| } |
| |
| ////////////////////////////////////////////////////////////////////////////// |
| |
| GrDrawState::AutoVertexAttribRestore::AutoVertexAttribRestore(GrDrawState* drawState) { |
| SkASSERT(drawState); |
| fDrawState = drawState; |
| fVAPtr = drawState->fVAPtr; |
| fVACount = drawState->fVACount; |
| fVAStride = drawState->fVAStride; |
| fDrawState->setDefaultVertexAttribs(); |
| } |
| |
| //////////////////////////////////////////////////////////////////////////////s |
| |
| bool GrDrawState::willEffectReadDstColor() const { |
| if (!this->isColorWriteDisabled()) { |
| this->calcColorInvariantOutput(); |
| if (fColorProcInfo.readsDst()) { |
| return true; |
| } |
| } |
| this->calcCoverageInvariantOutput(); |
| return fCoverageProcInfo.readsDst(); |
| } |
| |
| void GrDrawState::AutoRestoreEffects::set(GrDrawState* ds) { |
| if (fDrawState) { |
| // See the big comment on the class definition about GPs. |
| if (SK_InvalidUniqueID == fOriginalGPID) { |
| fDrawState->fGeometryProcessor.reset(NULL); |
| } else { |
| SkASSERT(fDrawState->getGeometryProcessor()->getUniqueID() == |
| fOriginalGPID); |
| fOriginalGPID = SK_InvalidUniqueID; |
| } |
| |
| int m = fDrawState->numColorStages() - fColorEffectCnt; |
| SkASSERT(m >= 0); |
| fDrawState->fColorStages.pop_back_n(m); |
| |
| int n = fDrawState->numCoverageStages() - fCoverageEffectCnt; |
| SkASSERT(n >= 0); |
| fDrawState->fCoverageStages.pop_back_n(n); |
| if (m + n > 0) { |
| fDrawState->fColorProcInfoValid = false; |
| fDrawState->fCoverageProcInfoValid = false; |
| } |
| SkDEBUGCODE(--fDrawState->fBlockEffectRemovalCnt;) |
| } |
| fDrawState = ds; |
| if (NULL != ds) { |
| SkASSERT(SK_InvalidUniqueID == fOriginalGPID); |
| if (NULL != ds->getGeometryProcessor()) { |
| fOriginalGPID = ds->getGeometryProcessor()->getUniqueID(); |
| } |
| fColorEffectCnt = ds->numColorStages(); |
| fCoverageEffectCnt = ds->numCoverageStages(); |
| SkDEBUGCODE(++ds->fBlockEffectRemovalCnt;) |
| } |
| } |
| |
| //////////////////////////////////////////////////////////////////////////////// |
| |
| // Some blend modes allow folding a fractional coverage value into the color's alpha channel, while |
| // others will blend incorrectly. |
| bool GrDrawState::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 GrDrawState::AutoViewMatrixRestore::restore() { |
| if (fDrawState) { |
| SkDEBUGCODE(--fDrawState->fBlockEffectRemovalCnt;) |
| fDrawState->fViewMatrix = fViewMatrix; |
| SkASSERT(fDrawState->numColorStages() >= fNumColorStages); |
| int numCoverageStages = fSavedCoordChanges.count() - fNumColorStages; |
| SkASSERT(fDrawState->numCoverageStages() >= numCoverageStages); |
| |
| int i = 0; |
| for (int s = 0; s < fNumColorStages; ++s, ++i) { |
| fDrawState->fColorStages[s].restoreCoordChange(fSavedCoordChanges[i]); |
| } |
| for (int s = 0; s < numCoverageStages; ++s, ++i) { |
| fDrawState->fCoverageStages[s].restoreCoordChange(fSavedCoordChanges[i]); |
| } |
| fDrawState = NULL; |
| } |
| } |
| |
| void GrDrawState::AutoViewMatrixRestore::set(GrDrawState* drawState, |
| const SkMatrix& preconcatMatrix) { |
| this->restore(); |
| |
| SkASSERT(NULL == fDrawState); |
| if (NULL == drawState || preconcatMatrix.isIdentity()) { |
| return; |
| } |
| fDrawState = drawState; |
| |
| fViewMatrix = drawState->getViewMatrix(); |
| drawState->fViewMatrix.preConcat(preconcatMatrix); |
| |
| this->doEffectCoordChanges(preconcatMatrix); |
| SkDEBUGCODE(++fDrawState->fBlockEffectRemovalCnt;) |
| } |
| |
| bool GrDrawState::AutoViewMatrixRestore::setIdentity(GrDrawState* drawState) { |
| this->restore(); |
| |
| if (NULL == drawState) { |
| return false; |
| } |
| |
| if (drawState->getViewMatrix().isIdentity()) { |
| return true; |
| } |
| |
| fViewMatrix = drawState->getViewMatrix(); |
| if (0 == drawState->numFragmentStages()) { |
| drawState->fViewMatrix.reset(); |
| fDrawState = drawState; |
| fNumColorStages = 0; |
| fSavedCoordChanges.reset(0); |
| SkDEBUGCODE(++fDrawState->fBlockEffectRemovalCnt;) |
| return true; |
| } else { |
| SkMatrix inv; |
| if (!fViewMatrix.invert(&inv)) { |
| return false; |
| } |
| drawState->fViewMatrix.reset(); |
| fDrawState = drawState; |
| this->doEffectCoordChanges(inv); |
| SkDEBUGCODE(++fDrawState->fBlockEffectRemovalCnt;) |
| return true; |
| } |
| } |
| |
| void GrDrawState::AutoViewMatrixRestore::doEffectCoordChanges(const SkMatrix& coordChangeMatrix) { |
| fSavedCoordChanges.reset(fDrawState->numFragmentStages()); |
| int i = 0; |
| |
| fNumColorStages = fDrawState->numColorStages(); |
| for (int s = 0; s < fNumColorStages; ++s, ++i) { |
| fDrawState->getColorStage(s).saveCoordChange(&fSavedCoordChanges[i]); |
| fDrawState->fColorStages[s].localCoordChange(coordChangeMatrix); |
| } |
| |
| int numCoverageStages = fDrawState->numCoverageStages(); |
| for (int s = 0; s < numCoverageStages; ++s, ++i) { |
| fDrawState->getCoverageStage(s).saveCoordChange(&fSavedCoordChanges[i]); |
| fDrawState->fCoverageStages[s].localCoordChange(coordChangeMatrix); |
| } |
| } |
| |
| //////////////////////////////////////////////////////////////////////////////// |
| |
| GrDrawState::~GrDrawState() { |
| SkASSERT(0 == fBlockEffectRemovalCnt); |
| } |
| |
| //////////////////////////////////////////////////////////////////////////////// |
| |
| GrDrawState::BlendOpt GrDrawState::getBlendOpt(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_BlendOpt; |
| } else { |
| *dstCoeff = kOne_GrBlendCoeff; |
| return kSkipDraw_BlendOpt; |
| } |
| } |
| |
| 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_BlendOpt; |
| } |
| } |
| } else if (this->isCoverageDrawing()) { |
| // we have coverage but we aren't distinguishing it from alpha by request. |
| return kCoverageAsAlpha_BlendOpt; |
| } 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_BlendOpt; |
| } |
| 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_BlendOpt; |
| } 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_BlendOpt; |
| } |
| } 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_BlendOpt; |
| } |
| } |
| |
| return kNone_BlendOpt; |
| } |
| |
| bool GrDrawState::srcAlphaWillBeOne() const { |
| this->calcColorInvariantOutput(); |
| if (this->isCoverageDrawing()) { |
| this->calcCoverageInvariantOutput(); |
| return (fColorProcInfo.isOpaque() && fCoverageProcInfo.isOpaque()); |
| } |
| return fColorProcInfo.isOpaque(); |
| } |
| |
| bool GrDrawState::willBlendWithDst() const { |
| if (!this->hasSolidCoverage()) { |
| return true; |
| } |
| |
| if (this->willEffectReadDstColor()) { |
| return true; |
| } |
| |
| if (GrBlendCoeffRefsDst(this->getSrcBlendCoeff())) { |
| return true; |
| } |
| |
| GrBlendCoeff dstCoeff = this->getDstBlendCoeff(); |
| if (!(kZero_GrBlendCoeff == dstCoeff || |
| (kISA_GrBlendCoeff == dstCoeff && this->srcAlphaWillBeOne()))) { |
| return true; |
| } |
| |
| return false; |
| } |
| |
| void GrDrawState::calcColorInvariantOutput() const { |
| if (!fColorProcInfoValid) { |
| GrColor color; |
| GrColorComponentFlags flags; |
| if (this->hasColorVertexAttribute()) { |
| if (fHints & kVertexColorsAreOpaque_Hint) { |
| flags = kA_GrColorComponentFlag; |
| color = 0xFF << GrColor_SHIFT_A; |
| } else { |
| flags = static_cast<GrColorComponentFlags>(0); |
| color = 0; |
| } |
| } else { |
| flags = kRGBA_GrColorComponentFlags; |
| color = this->getColor(); |
| } |
| fColorProcInfo.calcWithInitialValues(fColorStages.begin(), this->numColorStages(), |
| color, flags, false); |
| fColorProcInfoValid = true; |
| } |
| } |
| |
| void GrDrawState::calcCoverageInvariantOutput() const { |
| if (!fCoverageProcInfoValid) { |
| GrColor color; |
| GrColorComponentFlags flags; |
| // Check if per-vertex or constant color may have partial alpha |
| if (this->hasCoverageVertexAttribute()) { |
| flags = static_cast<GrColorComponentFlags>(0); |
| color = 0; |
| } else { |
| flags = kRGBA_GrColorComponentFlags; |
| color = this->getCoverageColor(); |
| } |
| fCoverageProcInfo.calcWithInitialValues(fCoverageStages.begin(), this->numCoverageStages(), |
| color, flags, true, fGeometryProcessor.get()); |
| fCoverageProcInfoValid = true; |
| } |
| } |
| |