C++ GrDrawState::hasCoverageVertexAttribute方法代码示例

void GrGLProgram::setCoverage(const GrDrawState& drawState,
                              GrColor coverage,
                              SharedGLState* sharedState) {
    const GrGLProgramDesc::KeyHeader& header = fDesc.getHeader();
    if (!drawState.hasCoverageVertexAttribute()) {
        switch (header.fCoverageInput) {
            case GrGLProgramDesc::kAttribute_ColorInput:
                if (sharedState->fConstAttribCoverage != coverage ||
                    sharedState->fConstAttribCoverageIndex != header.fCoverageAttributeIndex) {
                    // OpenGL ES only supports the float varieties of  glVertexAttrib
                    GrGLfloat c[4];
                    GrColorToRGBAFloat(coverage, c);
                    GL_CALL(VertexAttrib4fv(header.fCoverageAttributeIndex, c));
                    sharedState->fConstAttribCoverage = coverage;
                    sharedState->fConstAttribCoverageIndex = header.fCoverageAttributeIndex;
                }
                break;
            case GrGLProgramDesc::kUniform_ColorInput:
                if (fCoverage != coverage) {
                    // OpenGL ES doesn't support unsigned byte varieties of glUniform
                    GrGLfloat c[4];
                    GrColorToRGBAFloat(coverage, c);
                    fUniformManager.set4fv(fUniformHandles.fCoverageUni, 1, c);
                    fCoverage = coverage;
                }
                sharedState->fConstAttribCoverageIndex = -1;
                break;
            case GrGLProgramDesc::kSolidWhite_ColorInput:
            case GrGLProgramDesc::kTransBlack_ColorInput:
                sharedState->fConstAttribCoverageIndex = -1;
                break;
            default:
                GrCrash("Unknown coverage type.");
        }
    } else {
        sharedState->fConstAttribCoverageIndex = -1;
    }
}

void GrGLProgramDesc::Build(const GrDrawState& drawState,
                            bool isPoints,
                            GrDrawState::BlendOptFlags blendOpts,
                            GrBlendCoeff srcCoeff,
                            GrBlendCoeff dstCoeff,
                            const GrGpuGL* gpu,
                            const GrDeviceCoordTexture* dstCopy,
                            SkTArray<const GrEffectStage*, true>* colorStages,
                            SkTArray<const GrEffectStage*, true>* coverageStages,
                            GrGLProgramDesc* desc) {
    colorStages->reset();
    coverageStages->reset();

    // This should already have been caught
    SkASSERT(!(GrDrawState::kSkipDraw_BlendOptFlag & blendOpts));

    bool skipCoverage = SkToBool(blendOpts & GrDrawState::kEmitTransBlack_BlendOptFlag);

    bool skipColor = SkToBool(blendOpts & (GrDrawState::kEmitTransBlack_BlendOptFlag |
                                           GrDrawState::kEmitCoverage_BlendOptFlag));
    int firstEffectiveColorStage = 0;
    bool inputColorIsUsed = true;
    if (!skipColor) {
        firstEffectiveColorStage = drawState.numColorStages();
        while (firstEffectiveColorStage > 0 && inputColorIsUsed) {
            --firstEffectiveColorStage;
            const GrEffect* effect = drawState.getColorStage(firstEffectiveColorStage).getEffect()->get();
            inputColorIsUsed = effect->willUseInputColor();
        }
    }

    int firstEffectiveCoverageStage = 0;
    bool inputCoverageIsUsed = true;
    if (!skipCoverage) {
        firstEffectiveCoverageStage = drawState.numCoverageStages();
        while (firstEffectiveCoverageStage > 0 && inputCoverageIsUsed) {
            --firstEffectiveCoverageStage;
            const GrEffect* effect = drawState.getCoverageStage(firstEffectiveCoverageStage).getEffect()->get();
            inputCoverageIsUsed = effect->willUseInputColor();
        }
    }

    // The descriptor is used as a cache key. Thus when a field of the
    // descriptor will not affect program generation (because of the attribute
    // bindings in use or other descriptor field settings) it should be set
    // to a canonical value to avoid duplicate programs with different keys.

    bool requiresColorAttrib = !skipColor && drawState.hasColorVertexAttribute();
    bool requiresCoverageAttrib = !skipCoverage && drawState.hasCoverageVertexAttribute();
    // we only need the local coords if we're actually going to generate effect code
    bool requiresLocalCoordAttrib = !(skipCoverage  && skipColor) &&
                                    drawState.hasLocalCoordAttribute();

    bool colorIsTransBlack = SkToBool(blendOpts & GrDrawState::kEmitTransBlack_BlendOptFlag);
    bool colorIsSolidWhite = (blendOpts & GrDrawState::kEmitCoverage_BlendOptFlag) ||
                             (!requiresColorAttrib && 0xffffffff == drawState.getColor()) ||
                             (!inputColorIsUsed);

    int numEffects = (skipColor ? 0 : (drawState.numColorStages() - firstEffectiveColorStage)) +
                     (skipCoverage ? 0 : (drawState.numCoverageStages() - firstEffectiveCoverageStage));

    size_t newKeyLength = KeyLength(numEffects);
    bool allocChanged;
    desc->fKey.reset(newKeyLength, SkAutoMalloc::kAlloc_OnShrink, &allocChanged);
    if (allocChanged || !desc->fInitialized) {
        // make sure any padding in the header is zero if we we haven't used this allocation before.
        memset(desc->header(), 0, kHeaderSize);
    }
    // write the key length
    *desc->atOffset<uint32_t, kLengthOffset>() = SkToU32(newKeyLength);

    KeyHeader* header = desc->header();
    EffectKey* effectKeys = desc->effectKeys();

    int currEffectKey = 0;
    bool readsDst = false;
    bool readFragPosition = false;
    bool hasVertexCode = false;
    if (!skipColor) {
        for (int s = firstEffectiveColorStage; s < drawState.numColorStages(); ++s) {
            effectKeys[currEffectKey++] =
                get_key_and_update_stats(drawState.getColorStage(s), gpu->glCaps(),
                                         requiresLocalCoordAttrib, &readsDst, &readFragPosition,
                                         &hasVertexCode);
        }
    }
    if (!skipCoverage) {
        for (int s = firstEffectiveCoverageStage; s < drawState.numCoverageStages(); ++s) {
            effectKeys[currEffectKey++] =
                get_key_and_update_stats(drawState.getCoverageStage(s), gpu->glCaps(),
                                         requiresLocalCoordAttrib, &readsDst, &readFragPosition,
                                         &hasVertexCode);
        }
    }

    header->fHasVertexCode = hasVertexCode || requiresLocalCoordAttrib;
    header->fEmitsPointSize = isPoints;

    // Currently the experimental GS will only work with triangle prims (and it doesn't do anything
    // other than pass through values from the VS to the FS anyway).
//.........这里部分代码省略.........

void GrGLProgramDesc::Build(const GrDrawState& drawState,
                            bool isPoints,
                            GrDrawState::BlendOptFlags blendOpts,
                            GrBlendCoeff srcCoeff,
                            GrBlendCoeff dstCoeff,
                            const GrGpuGL* gpu,
                            const GrDeviceCoordTexture* dstCopy,
                            GrGLProgramDesc* desc) {

    // This should already have been caught
    GrAssert(!(GrDrawState::kSkipDraw_BlendOptFlag & blendOpts));

    bool skipCoverage = SkToBool(blendOpts & GrDrawState::kEmitTransBlack_BlendOptFlag);

    bool skipColor = SkToBool(blendOpts & (GrDrawState::kEmitTransBlack_BlendOptFlag |
                                           GrDrawState::kEmitCoverage_BlendOptFlag));

    // The descriptor is used as a cache key. Thus when a field of the
    // descriptor will not affect program generation (because of the attribute
    // bindings in use or other descriptor field settings) it should be set
    // to a canonical value to avoid duplicate programs with different keys.


    desc->fEmitsPointSize = isPoints;

    bool requiresColorAttrib = !skipColor && drawState.hasColorVertexAttribute();
    bool requiresCoverageAttrib = !skipCoverage && drawState.hasCoverageVertexAttribute();
    // we only need the local coords if we're actually going to generate effect code
    bool requiresLocalCoordAttrib = !(skipCoverage  && skipColor) &&
                                    drawState.hasLocalCoordAttribute();

    // fColorInput/fCoverageInput records how colors are specified for the program so we strip the
    // bits from the bindings to avoid false negatives when searching for an existing program in the
    // cache.

    desc->fColorFilterXfermode = skipColor ? SkXfermode::kDst_Mode : drawState.getColorFilterMode();


    bool colorIsTransBlack = SkToBool(blendOpts & GrDrawState::kEmitTransBlack_BlendOptFlag);
    bool colorIsSolidWhite = (blendOpts & GrDrawState::kEmitCoverage_BlendOptFlag) ||
                             (!requiresColorAttrib && 0xffffffff == drawState.getColor());
    if (colorIsTransBlack) {
        desc->fColorInput = kTransBlack_ColorInput;
    } else if (colorIsSolidWhite) {
        desc->fColorInput = kSolidWhite_ColorInput;
    } else if (GR_GL_NO_CONSTANT_ATTRIBUTES && !requiresColorAttrib) {
        desc->fColorInput = kUniform_ColorInput;
    } else {
        desc->fColorInput = kAttribute_ColorInput;
    }

    bool covIsSolidWhite = !requiresCoverageAttrib && 0xffffffff == drawState.getCoverage();

    if (skipCoverage) {
        desc->fCoverageInput = kTransBlack_ColorInput;
    } else if (covIsSolidWhite) {
        desc->fCoverageInput = kSolidWhite_ColorInput;
    } else if (GR_GL_NO_CONSTANT_ATTRIBUTES && !requiresCoverageAttrib) {
        desc->fCoverageInput = kUniform_ColorInput;
    } else {
        desc->fCoverageInput = kAttribute_ColorInput;
    }

    bool readsDst = false;
    int lastEnabledStage = -1;

    for (int s = 0; s < GrDrawState::kNumStages; ++s) {

        bool skip = s < drawState.getFirstCoverageStage() ? skipColor : skipCoverage;
        if (!skip && drawState.isStageEnabled(s)) {
            lastEnabledStage = s;
            const GrEffectRef& effect = *drawState.getStage(s).getEffect();
            const GrBackendEffectFactory& factory = effect->getFactory();
            GrDrawEffect drawEffect(drawState.getStage(s), requiresLocalCoordAttrib);
            desc->fEffectKeys[s] = factory.glEffectKey(drawEffect, gpu->glCaps());
            if (effect->willReadDst()) {
                readsDst = true;
            }
        } else {
            desc->fEffectKeys[s] = 0;
        }
    }

    if (readsDst) {
        GrAssert(NULL != dstCopy);
        desc->fDstRead = GrGLShaderBuilder::KeyForDstRead(dstCopy->texture(), gpu->glCaps());
        GrAssert(0 != desc->fDstRead);
    } else {
        desc->fDstRead = 0;
    }

    desc->fCoverageOutput = kModulate_CoverageOutput;

    // Currently the experimental GS will only work with triangle prims (and it doesn't do anything
    // other than pass through values from the VS to the FS anyway).
#if GR_GL_EXPERIMENTAL_GS
#if 0
    desc->fExperimentalGS = gpu->caps().geometryShaderSupport();
#else
    desc->fExperimentalGS = false;
//.........这里部分代码省略.........

bool GrGLProgramDesc::Build(const GrDrawState& drawState,
                            GrGpu::DrawType drawType,
                            GrDrawState::BlendOptFlags blendOpts,
                            GrBlendCoeff srcCoeff,
                            GrBlendCoeff dstCoeff,
                            const GrGpuGL* gpu,
                            const GrDeviceCoordTexture* dstCopy,
                            const GrEffectStage** geometryProcessor,
                            SkTArray<const GrEffectStage*, true>* colorStages,
                            SkTArray<const GrEffectStage*, true>* coverageStages,
                            GrGLProgramDesc* desc) {
    colorStages->reset();
    coverageStages->reset();

    // This should already have been caught
    SkASSERT(!(GrDrawState::kSkipDraw_BlendOptFlag & blendOpts));

    bool skipCoverage = SkToBool(blendOpts & GrDrawState::kEmitTransBlack_BlendOptFlag);

    bool skipColor = SkToBool(blendOpts & (GrDrawState::kEmitTransBlack_BlendOptFlag |
                                           GrDrawState::kEmitCoverage_BlendOptFlag));

    int firstEffectiveColorStage = 0;
    bool inputColorIsUsed = true;

    if (!skipColor) {
        firstEffectiveColorStage = drawState.numColorStages();
        while (firstEffectiveColorStage > 0 && inputColorIsUsed) {
            --firstEffectiveColorStage;
            const GrEffect* effect = drawState.getColorStage(firstEffectiveColorStage).getEffect();
            inputColorIsUsed = effect->willUseInputColor();
        }
    }

    int firstEffectiveCoverageStage = 0;
    bool inputCoverageIsUsed = true;
    if (!skipCoverage) {
        firstEffectiveCoverageStage = drawState.numCoverageStages();
        while (firstEffectiveCoverageStage > 0 && inputCoverageIsUsed) {
            --firstEffectiveCoverageStage;
            const GrEffect* effect = drawState.getCoverageStage(firstEffectiveCoverageStage).getEffect();
            inputCoverageIsUsed = effect->willUseInputColor();
        }
    }

    // The descriptor is used as a cache key. Thus when a field of the
    // descriptor will not affect program generation (because of the attribute
    // bindings in use or other descriptor field settings) it should be set
    // to a canonical value to avoid duplicate programs with different keys.

    bool requiresColorAttrib = !skipColor && drawState.hasColorVertexAttribute();
    bool requiresCoverageAttrib = !skipCoverage && drawState.hasCoverageVertexAttribute();
    // we only need the local coords if we're actually going to generate effect code
    bool requiresLocalCoordAttrib = !(skipCoverage  && skipColor) &&
                                    drawState.hasLocalCoordAttribute();

    bool readsDst = false;
    bool readFragPosition = false;

    // Provide option for shader programs without vertex shader only when drawing paths.
    bool requiresVertexShader = !GrGpu::IsPathRenderingDrawType(drawType);

    int numStages = 0;
    if (drawState.hasGeometryProcessor()) {
        numStages++;
    }
    if (!skipColor) {
        numStages += drawState.numColorStages() - firstEffectiveColorStage;
    }
    if (!skipCoverage) {
        numStages += drawState.numCoverageStages() - firstEffectiveCoverageStage;
    }
    GR_STATIC_ASSERT(0 == kEffectKeyOffsetsAndLengthOffset % sizeof(uint32_t));
    // Make room for everything up to and including the array of offsets to effect keys.
    desc->fKey.reset();
    desc->fKey.push_back_n(kEffectKeyOffsetsAndLengthOffset + 2 * sizeof(uint16_t) * numStages);

    int offsetAndSizeIndex = 0;
    bool effectKeySuccess = true;

    KeyHeader* header = desc->header();
    // make sure any padding in the header is zeroed.
    memset(desc->header(), 0, kHeaderSize);

    // We can only have one effect which touches the vertex shader
    if (drawState.hasGeometryProcessor()) {
        uint16_t* offsetAndSize =
                reinterpret_cast<uint16_t*>(desc->fKey.begin() + kEffectKeyOffsetsAndLengthOffset +
                                            offsetAndSizeIndex * 2 * sizeof(uint16_t));

            GrEffectKeyBuilder b(&desc->fKey);
            uint16_t effectKeySize;
            uint32_t effectOffset = desc->fKey.count();
            effectKeySuccess |= GetEffectKeyAndUpdateStats(
                                    *drawState.getGeometryProcessor(), gpu->glCaps(),
                                    requiresLocalCoordAttrib, &b,
                                    &effectKeySize, &readsDst,
                                    &readFragPosition, &requiresVertexShader);
            effectKeySuccess |= (effectOffset <= SK_MaxU16);

//.........这里部分代码省略.........