| /* |
| * 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 "src/gpu/effects/GrGaussianConvolutionFragmentProcessor.h" |
| |
| #include "src/gpu/GrTexture.h" |
| #include "src/gpu/GrTextureProxy.h" |
| #include "src/gpu/effects/GrTextureEffect.h" |
| #include "src/gpu/glsl/GrGLSLFragmentProcessor.h" |
| #include "src/gpu/glsl/GrGLSLFragmentShaderBuilder.h" |
| #include "src/gpu/glsl/GrGLSLProgramDataManager.h" |
| #include "src/gpu/glsl/GrGLSLUniformHandler.h" |
| |
| // For brevity |
| using UniformHandle = GrGLSLProgramDataManager::UniformHandle; |
| using Direction = GrGaussianConvolutionFragmentProcessor::Direction; |
| |
| static constexpr int radius_to_width(int r) { return 2*r + 1; } |
| |
| class GrGaussianConvolutionFragmentProcessor::Impl : public GrGLSLFragmentProcessor { |
| public: |
| void emitCode(EmitArgs&) override; |
| |
| static inline void GenKey(const GrProcessor&, const GrShaderCaps&, GrProcessorKeyBuilder*); |
| |
| protected: |
| void onSetData(const GrGLSLProgramDataManager&, const GrFragmentProcessor&) override; |
| |
| private: |
| UniformHandle fKernelUni; |
| UniformHandle fIncrementUni; |
| |
| using INHERITED = GrGLSLFragmentProcessor; |
| }; |
| |
| void GrGaussianConvolutionFragmentProcessor::Impl::emitCode(EmitArgs& args) { |
| const GrGaussianConvolutionFragmentProcessor& ce = |
| args.fFp.cast<GrGaussianConvolutionFragmentProcessor>(); |
| |
| GrGLSLUniformHandler* uniformHandler = args.fUniformHandler; |
| |
| const char* inc; |
| fIncrementUni = uniformHandler->addUniform(&ce, kFragment_GrShaderFlag, kHalf2_GrSLType, |
| "Increment", &inc); |
| |
| int width = radius_to_width(ce.fRadius); |
| |
| int arrayCount = (width + 3) / 4; |
| SkASSERT(4 * arrayCount >= width); |
| |
| const char* kernel; |
| fKernelUni = uniformHandler->addUniformArray(&ce, kFragment_GrShaderFlag, kHalf4_GrSLType, |
| "Kernel", arrayCount, &kernel); |
| |
| GrGLSLFPFragmentBuilder* fragBuilder = args.fFragBuilder; |
| |
| fragBuilder->codeAppendf("%s = half4(0, 0, 0, 0);", args.fOutputColor); |
| |
| fragBuilder->codeAppendf("float2 coord = %s - %d.0 * %s;", args.fSampleCoord, ce.fRadius, inc); |
| fragBuilder->codeAppend("float2 coordSampled = half2(0, 0);"); |
| |
| // Manually unroll loop because some drivers don't; yields 20-30% speedup. |
| static constexpr const char* kVecSuffix[4] = {".x", ".y", ".z", ".w"}; |
| for (int i = 0; i < width; i++) { |
| SkString kernelIndex; |
| kernelIndex.printf("%s[%d]", kernel, i/4); |
| kernelIndex.append(kVecSuffix[i & 0x3]); |
| |
| fragBuilder->codeAppend("coordSampled = coord;"); |
| auto sample = this->invokeChild(0, args, "coordSampled"); |
| fragBuilder->codeAppendf("%s += %s", args.fOutputColor, sample.c_str()); |
| fragBuilder->codeAppendf(" * %s;", kernelIndex.c_str()); |
| fragBuilder->codeAppendf("coord += %s;", inc); |
| } |
| fragBuilder->codeAppendf("%s *= %s;", args.fOutputColor, args.fInputColor); |
| } |
| |
| void GrGaussianConvolutionFragmentProcessor::Impl::onSetData(const GrGLSLProgramDataManager& pdman, |
| const GrFragmentProcessor& processor) { |
| const auto& conv = processor.cast<GrGaussianConvolutionFragmentProcessor>(); |
| |
| float increment[2] = {}; |
| increment[static_cast<int>(conv.fDirection)] = 1; |
| pdman.set2fv(fIncrementUni, 1, increment); |
| |
| int width = radius_to_width(conv.fRadius); |
| int arrayCount = (width + 3)/4; |
| SkDEBUGCODE(size_t arraySize = 4*arrayCount;) |
| SkASSERT(arraySize >= static_cast<size_t>(width)); |
| SkASSERT(arraySize <= SK_ARRAY_COUNT(GrGaussianConvolutionFragmentProcessor::fKernel)); |
| pdman.set4fv(fKernelUni, arrayCount, conv.fKernel); |
| } |
| |
| void GrGaussianConvolutionFragmentProcessor::Impl::GenKey(const GrProcessor& processor, |
| const GrShaderCaps&, |
| GrProcessorKeyBuilder* b) { |
| const auto& conv = processor.cast<GrGaussianConvolutionFragmentProcessor>(); |
| b->add32(conv.fRadius); |
| } |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| void SkFillIn1DGaussianKernel(float* kernel, float gaussianSigma, int radius) { |
| const float twoSigmaSqrd = 2.0f * gaussianSigma * gaussianSigma; |
| int width = radius_to_width(radius); |
| if (SkScalarNearlyZero(twoSigmaSqrd, SK_ScalarNearlyZero)) { |
| for (int i = 0; i < width; ++i) { |
| kernel[i] = 0.0f; |
| } |
| return; |
| } |
| |
| const float denom = 1.0f / twoSigmaSqrd; |
| |
| float sum = 0.0f; |
| for (int i = 0; i < width; ++i) { |
| float x = static_cast<float>(i - radius); |
| // Note that the constant term (1/(sqrt(2*pi*sigma^2)) of the Gaussian |
| // is dropped here, since we renormalize the kernel below. |
| kernel[i] = sk_float_exp(-x * x * denom); |
| sum += kernel[i]; |
| } |
| // Normalize the kernel |
| float scale = 1.0f / sum; |
| for (int i = 0; i < width; ++i) { |
| kernel[i] *= scale; |
| } |
| } |
| |
| std::unique_ptr<GrFragmentProcessor> GrGaussianConvolutionFragmentProcessor::Make( |
| GrSurfaceProxyView view, |
| SkAlphaType alphaType, |
| Direction dir, |
| int halfWidth, |
| float gaussianSigma, |
| GrSamplerState::WrapMode wm, |
| const SkIRect& subset, |
| const SkIRect* pixelDomain, |
| const GrCaps& caps) { |
| std::unique_ptr<GrFragmentProcessor> child; |
| GrSamplerState sampler(wm, GrSamplerState::Filter::kNearest); |
| if (pixelDomain) { |
| // Inset because we expect to be invoked at pixel centers. |
| SkRect domain = SkRect::Make(*pixelDomain).makeInset(0.5, 0.5f); |
| switch (dir) { |
| case Direction::kX: domain.outset(halfWidth, 0); break; |
| case Direction::kY: domain.outset(0, halfWidth); break; |
| } |
| child = GrTextureEffect::MakeSubset(std::move(view), alphaType, SkMatrix::I(), sampler, |
| SkRect::Make(subset), domain, caps); |
| } else { |
| child = GrTextureEffect::MakeSubset(std::move(view), alphaType, SkMatrix::I(), sampler, |
| SkRect::Make(subset), caps); |
| } |
| return std::unique_ptr<GrFragmentProcessor>(new GrGaussianConvolutionFragmentProcessor( |
| std::move(child), dir, halfWidth, gaussianSigma)); |
| } |
| |
| GrGaussianConvolutionFragmentProcessor::GrGaussianConvolutionFragmentProcessor( |
| std::unique_ptr<GrFragmentProcessor> child, |
| Direction direction, |
| int radius, |
| float gaussianSigma) |
| : INHERITED(kGrGaussianConvolutionFragmentProcessor_ClassID, |
| ProcessorOptimizationFlags(child.get())) |
| , fRadius(radius) |
| , fDirection(direction) { |
| this->registerChild(std::move(child), SkSL::SampleUsage::Explicit()); |
| SkASSERT(radius <= kMaxKernelRadius); |
| SkFillIn1DGaussianKernel(fKernel, gaussianSigma, fRadius); |
| this->setUsesSampleCoordsDirectly(); |
| } |
| |
| GrGaussianConvolutionFragmentProcessor::GrGaussianConvolutionFragmentProcessor( |
| const GrGaussianConvolutionFragmentProcessor& that) |
| : INHERITED(kGrGaussianConvolutionFragmentProcessor_ClassID, that.optimizationFlags()) |
| , fRadius(that.fRadius) |
| , fDirection(that.fDirection) { |
| this->cloneAndRegisterAllChildProcessors(that); |
| memcpy(fKernel, that.fKernel, radius_to_width(fRadius) * sizeof(float)); |
| this->setUsesSampleCoordsDirectly(); |
| } |
| |
| void GrGaussianConvolutionFragmentProcessor::onGetGLSLProcessorKey(const GrShaderCaps& caps, |
| GrProcessorKeyBuilder* b) const { |
| Impl::GenKey(*this, caps, b); |
| } |
| |
| GrGLSLFragmentProcessor* GrGaussianConvolutionFragmentProcessor::onCreateGLSLInstance() const { |
| return new Impl; |
| } |
| |
| bool GrGaussianConvolutionFragmentProcessor::onIsEqual(const GrFragmentProcessor& sBase) const { |
| const auto& that = sBase.cast<GrGaussianConvolutionFragmentProcessor>(); |
| return fRadius == that.fRadius && fDirection == that.fDirection && |
| std::equal(fKernel, fKernel + radius_to_width(fRadius), that.fKernel); |
| } |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| GR_DEFINE_FRAGMENT_PROCESSOR_TEST(GrGaussianConvolutionFragmentProcessor); |
| |
| #if GR_TEST_UTILS |
| std::unique_ptr<GrFragmentProcessor> GrGaussianConvolutionFragmentProcessor::TestCreate( |
| GrProcessorTestData* d) { |
| auto [view, ct, at] = d->randomView(); |
| |
| Direction dir = d->fRandom->nextBool() ? Direction::kY : Direction::kX; |
| SkIRect subset{ |
| static_cast<int>(d->fRandom->nextRangeU(0, view.width() - 1)), |
| static_cast<int>(d->fRandom->nextRangeU(0, view.height() - 1)), |
| static_cast<int>(d->fRandom->nextRangeU(0, view.width() - 1)), |
| static_cast<int>(d->fRandom->nextRangeU(0, view.height() - 1)), |
| }; |
| subset.sort(); |
| |
| auto wm = static_cast<GrSamplerState::WrapMode>( |
| d->fRandom->nextULessThan(GrSamplerState::kWrapModeCount)); |
| int radius = d->fRandom->nextRangeU(1, kMaxKernelRadius); |
| float sigma = radius / 3.f; |
| SkIRect temp; |
| SkIRect* domain = nullptr; |
| if (d->fRandom->nextBool()) { |
| temp = { |
| static_cast<int>(d->fRandom->nextRangeU(0, view.width() - 1)), |
| static_cast<int>(d->fRandom->nextRangeU(0, view.height() - 1)), |
| static_cast<int>(d->fRandom->nextRangeU(0, view.width() - 1)), |
| static_cast<int>(d->fRandom->nextRangeU(0, view.height() - 1)), |
| }; |
| temp.sort(); |
| domain = &temp; |
| } |
| |
| return GrGaussianConvolutionFragmentProcessor::Make(std::move(view), at, dir, radius, sigma, wm, |
| subset, domain, *d->caps()); |
| } |
| #endif |