| /* |
| * 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 "GrPaint.h" |
| |
| bool GrDrawState::setIdentityViewMatrix() { |
| if (fColorStages.count() || fCoverageStages.count()) { |
| SkMatrix invVM; |
| if (!fCommon.fViewMatrix.invert(&invVM)) { |
| // sad trombone sound |
| return false; |
| } |
| for (int s = 0; s < fColorStages.count(); ++s) { |
| fColorStages[s].localCoordChange(invVM); |
| } |
| for (int s = 0; s < fCoverageStages.count(); ++s) { |
| fCoverageStages[s].localCoordChange(invVM); |
| } |
| } |
| fCommon.fViewMatrix.reset(); |
| return true; |
| } |
| |
| void GrDrawState::setFromPaint(const GrPaint& paint, const SkMatrix& vm, GrRenderTarget* rt) { |
| SkASSERT(0 == fBlockEffectRemovalCnt || 0 == this->numTotalStages()); |
| |
| 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); |
| |
| fCommon.fViewMatrix = vm; |
| |
| // These have no equivalent in GrPaint, set them to defaults |
| fCommon.fBlendConstant = 0x0; |
| fCommon.fDrawFace = kBoth_DrawFace; |
| fCommon.fStencilSettings.setDisabled(); |
| this->resetStateFlags(); |
| |
| // Enable the clip bit |
| this->enableState(GrDrawState::kClip_StateBit); |
| |
| this->setColor(paint.getColor()); |
| this->setCoverage4(paint.getCoverage()); |
| this->setState(GrDrawState::kDither_StateBit, paint.isDither()); |
| this->setState(GrDrawState::kHWAntialias_StateBit, paint.isAntiAlias()); |
| |
| this->setBlendFunc(paint.getSrcBlendCoeff(), paint.getDstBlendCoeff()); |
| this->setColorFilter(paint.getColorFilterColor(), paint.getColorFilterMode()); |
| this->setCoverage(paint.getCoverage()); |
| } |
| |
| //////////////////////////////////////////////////////////////////////////////// |
| |
| static size_t vertex_size(const GrVertexAttrib* attribs, int count) { |
| // this works as long as we're 4 byte-aligned |
| #if GR_DEBUG |
| uint32_t overlapCheck = 0; |
| #endif |
| SkASSERT(count <= GrDrawState::kMaxVertexAttribCnt); |
| size_t size = 0; |
| for (int index = 0; index < count; ++index) { |
| size_t attribSize = GrVertexAttribTypeSize(attribs[index].fType); |
| size += attribSize; |
| #if GR_DEBUG |
| size_t dwordCount = attribSize >> 2; |
| uint32_t mask = (1 << dwordCount)-1; |
| size_t offsetShift = attribs[index].fOffset >> 2; |
| SkASSERT(!(overlapCheck & (mask << offsetShift))); |
| overlapCheck |= (mask << offsetShift); |
| #endif |
| } |
| return size; |
| } |
| |
| size_t GrDrawState::getVertexSize() const { |
| return vertex_size(fCommon.fVAPtr, fCommon.fVACount); |
| } |
| |
| //////////////////////////////////////////////////////////////////////////////// |
| |
| void GrDrawState::setVertexAttribs(const GrVertexAttrib* attribs, int count) { |
| SkASSERT(count <= kMaxVertexAttribCnt); |
| |
| fCommon.fVAPtr = attribs; |
| fCommon.fVACount = count; |
| |
| // Set all the indices to -1 |
| memset(fCommon.fFixedFunctionVertexAttribIndices, |
| 0xff, |
| sizeof(fCommon.fFixedFunctionVertexAttribIndices)); |
| #if GR_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 == fCommon.fFixedFunctionVertexAttribIndices[attribs[i].fBinding]); |
| SkASSERT(GrFixedFunctionVertexAttribVectorCount(attribs[i].fBinding) == |
| GrVertexAttribTypeVectorCount(attribs[i].fType)); |
| fCommon.fFixedFunctionVertexAttribIndices[attribs[i].fBinding] = i; |
| } |
| #if GR_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 |
| } |
| // Positions must be specified. |
| SkASSERT(-1 != fCommon.fFixedFunctionVertexAttribIndices[kPosition_GrVertexAttribBinding]); |
| } |
| |
| //////////////////////////////////////////////////////////////////////////////// |
| |
| void GrDrawState::setDefaultVertexAttribs() { |
| static const GrVertexAttrib kPositionAttrib = |
| {kVec2f_GrVertexAttribType, 0, kPosition_GrVertexAttribBinding}; |
| |
| fCommon.fVAPtr = &kPositionAttrib; |
| fCommon.fVACount = 1; |
| |
| // set all the fixed function indices to -1 except position. |
| memset(fCommon.fFixedFunctionVertexAttribIndices, |
| 0xff, |
| sizeof(fCommon.fFixedFunctionVertexAttribIndices)); |
| fCommon.fFixedFunctionVertexAttribIndices[kPosition_GrVertexAttribBinding] = 0; |
| } |
| |
| //////////////////////////////////////////////////////////////////////////////// |
| |
| 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); |
| } |
| int totalStages = fColorStages.count() + fCoverageStages.count(); |
| for (int s = 0; s < totalStages; ++s) { |
| int covIdx = s - fColorStages.count(); |
| const GrEffectStage& stage = covIdx < 0 ? fColorStages[s] : fCoverageStages[covIdx]; |
| const GrEffectRef* effect = stage.getEffect(); |
| SkASSERT(NULL != effect); |
| // 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 int* attributeIndices = stage.getVertexAttribIndices(); |
| int numAttributes = stage.getVertexAttribIndexCount(); |
| for (int i = 0; i < numAttributes; ++i) { |
| int attribIndex = attributeIndices[i]; |
| if (attribIndex >= fCommon.fVACount || |
| kEffect_GrVertexAttribBinding != fCommon.fVAPtr[attribIndex].fBinding) { |
| return false; |
| } |
| |
| GrSLType effectSLType = (*effect)->vertexAttribType(i); |
| GrVertexAttribType attribType = fCommon.fVAPtr[attribIndex].fType; |
| int slVecCount = GrSLTypeVectorCount(effectSLType); |
| int attribVecCount = GrVertexAttribTypeVectorCount(attribType); |
| if (slVecCount != attribVecCount || |
| (static_cast<GrSLType>(-1) != slTypes[attribIndex] && |
| slTypes[attribIndex] != effectSLType)) { |
| return false; |
| } |
| slTypes[attribIndex] = effectSLType; |
| } |
| } |
| |
| return true; |
| } |
| |
| bool GrDrawState::willEffectReadDstColor() const { |
| if (!this->isColorWriteDisabled()) { |
| for (int s = 0; s < fColorStages.count(); ++s) { |
| if ((*fColorStages[s].getEffect())->willReadDstColor()) { |
| return true; |
| } |
| } |
| } |
| for (int s = 0; s < fCoverageStages.count(); ++s) { |
| if ((*fCoverageStages[s].getEffect())->willReadDstColor()) { |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| //////////////////////////////////////////////////////////////////////////////// |
| |
| bool GrDrawState::srcAlphaWillBeOne() const { |
| uint32_t validComponentFlags; |
| GrColor color; |
| // Check if per-vertex or constant color may have partial alpha |
| if (this->hasColorVertexAttribute()) { |
| 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 < fColorStages.count(); ++s) { |
| const GrEffectRef* effect = fColorStages[s].getEffect(); |
| (*effect)->getConstantColorComponents(&color, &validComponentFlags); |
| } |
| |
| // Check if the color filter could introduce an alpha. |
| // We could skip the above work when this is true, but it is rare and the right fix is to make |
| // the color filter a GrEffect and implement getConstantColorComponents() for it. |
| if (SkXfermode::kDst_Mode != this->getColorFilterMode()) { |
| validComponentFlags = 0; |
| } |
| |
| // Check whether coverage is treated as color. If so we run through the coverage computation. |
| if (this->isCoverageDrawing()) { |
| GrColor coverageColor = this->getCoverage(); |
| GrColor oldColor = color; |
| color = 0; |
| for (int c = 0; c < 4; ++c) { |
| if (validComponentFlags & (1 << c)) { |
| U8CPU a = (oldColor >> (c * 8)) & 0xff; |
| U8CPU b = (coverageColor >> (c * 8)) & 0xff; |
| color |= (SkMulDiv255Round(a, b) << (c * 8)); |
| } |
| } |
| for (int s = 0; s < fCoverageStages.count(); ++s) { |
| const GrEffectRef* effect = fCoverageStages[s].getEffect(); |
| (*effect)->getConstantColorComponents(&color, &validComponentFlags); |
| } |
| } |
| return (kA_GrColorComponentFlag & validComponentFlags) && 0xff == GrColorUnpackA(color); |
| } |
| |
| bool GrDrawState::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 = fCommon.fCoverage; |
| validComponentFlags = kRGBA_GrColorComponentFlags; |
| } |
| |
| // Run through the coverage stages and see if the coverage will be all ones at the end. |
| for (int s = 0; s < fCoverageStages.count(); ++s) { |
| const GrEffectRef* effect = fCoverageStages[s].getEffect(); |
| (*effect)->getConstantColorComponents(&coverage, &validComponentFlags); |
| } |
| return (kRGBA_GrColorComponentFlags == validComponentFlags) && (0xffffffff == coverage); |
| } |
| |
| //////////////////////////////////////////////////////////////////////////////// |
| |
| // 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 == fCommon.fDstBlend || |
| kISA_GrBlendCoeff == fCommon.fDstBlend || |
| kISC_GrBlendCoeff == fCommon.fDstBlend || |
| this->isCoverageDrawing(); |
| } |
| |
| GrDrawState::BlendOptFlags GrDrawState::getBlendOpts(bool forceCoverage, |
| GrBlendCoeff* srcCoeff, |
| GrBlendCoeff* dstCoeff) const { |
| |
| GrBlendCoeff bogusSrcCoeff, bogusDstCoeff; |
| if (NULL == srcCoeff) { |
| srcCoeff = &bogusSrcCoeff; |
| } |
| *srcCoeff = this->getSrcBlendCoeff(); |
| |
| if (NULL == dstCoeff) { |
| dstCoeff = &bogusDstCoeff; |
| } |
| *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); |
| |
| bool covIsZero = !this->isCoverageDrawing() && |
| !this->hasCoverageVertexAttribute() && |
| 0 == this->getCoverage(); |
| // 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). The same applies when coverage is known to be 0. |
| if ((kZero_GrBlendCoeff == *srcCoeff && dstCoeffIsOne) || covIsZero) { |
| if (this->getStencil().doesWrite()) { |
| return kDisableBlend_BlendOptFlag | |
| kEmitCoverage_BlendOptFlag; |
| } else { |
| return kSkipDraw_BlendOptFlag; |
| } |
| } |
| |
| // check for coverage due to constant coverage, per-vertex coverage, or coverage stage |
| bool hasCoverage = forceCoverage || |
| 0xffffffff != this->getCoverage() || |
| this->hasCoverageVertexAttribute() || |
| fCoverageStages.count() > 0; |
| |
| // 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 |
| return kDisableBlend_BlendOptFlag; |
| } 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 kDisableBlend_BlendOptFlag | 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; |
| } |
| } |
| if (kOne_GrBlendCoeff == *srcCoeff && |
| kZero_GrBlendCoeff == *dstCoeff && |
| this->willEffectReadDstColor()) { |
| // In this case the shader will fully resolve the color, coverage, and dst and we don't |
| // need blending. |
| return kDisableBlend_BlendOptFlag; |
| } |
| return kNone_BlendOpt; |
| } |
| |
| //////////////////////////////////////////////////////////////////////////////// |
| |
| void GrDrawState::AutoViewMatrixRestore::restore() { |
| if (NULL != fDrawState) { |
| GR_DEBUGCODE(--fDrawState->fBlockEffectRemovalCnt;) |
| fDrawState->fCommon.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->fCommon.fViewMatrix.preConcat(preconcatMatrix); |
| |
| this->doEffectCoordChanges(preconcatMatrix); |
| GR_DEBUGCODE(++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->numTotalStages()) { |
| drawState->fCommon.fViewMatrix.reset(); |
| fDrawState = drawState; |
| fNumColorStages = 0; |
| fSavedCoordChanges.reset(0); |
| GR_DEBUGCODE(++fDrawState->fBlockEffectRemovalCnt;) |
| return true; |
| } else { |
| SkMatrix inv; |
| if (!fViewMatrix.invert(&inv)) { |
| return false; |
| } |
| drawState->fCommon.fViewMatrix.reset(); |
| fDrawState = drawState; |
| this->doEffectCoordChanges(inv); |
| GR_DEBUGCODE(++fDrawState->fBlockEffectRemovalCnt;) |
| return true; |
| } |
| } |
| |
| void GrDrawState::AutoViewMatrixRestore::doEffectCoordChanges(const SkMatrix& coordChangeMatrix) { |
| fSavedCoordChanges.reset(fDrawState->numTotalStages()); |
| int i = 0; |
| |
| fNumColorStages = fDrawState->numColorStages(); |
| for (int s = 0; s < fNumColorStages; ++s, ++i) { |
| fDrawState->fColorStages[s].saveCoordChange(&fSavedCoordChanges[i]); |
| fDrawState->fColorStages[s].localCoordChange(coordChangeMatrix); |
| } |
| |
| int numCoverageStages = fDrawState->numCoverageStages(); |
| for (int s = 0; s < numCoverageStages; ++s, ++i) { |
| fDrawState->fCoverageStages[s].saveCoordChange(&fSavedCoordChanges[i]); |
| fDrawState->fCoverageStages[s].localCoordChange(coordChangeMatrix); |
| } |
| } |
