| /* |
| * 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 "GrConvolutionEffect.h" |
| #include "gl/GrGLProgramStage.h" |
| #include "gl/GrGLSL.h" |
| #include "gl/GrGLTexture.h" |
| #include "GrProgramStageFactory.h" |
| |
| class GrGLConvolutionEffect : public GrGLProgramStage { |
| public: |
| GrGLConvolutionEffect(const GrProgramStageFactory& factory, |
| const GrCustomStage& stage); |
| |
| virtual void setupVariables(GrGLShaderBuilder* state, |
| int stage) SK_OVERRIDE; |
| virtual void emitVS(GrGLShaderBuilder* state, |
| const char* vertexCoords) SK_OVERRIDE; |
| virtual void emitFS(GrGLShaderBuilder* state, |
| const char* outputColor, |
| const char* inputColor, |
| const char* samplerName) SK_OVERRIDE; |
| |
| virtual void initUniforms(const GrGLInterface*, int programID) SK_OVERRIDE; |
| |
| virtual void setData(const GrGLInterface*, |
| const GrCustomStage&, |
| const GrRenderTarget*, |
| int stageNum) SK_OVERRIDE; |
| |
| static inline StageKey GenKey(const GrCustomStage&); |
| |
| private: |
| int width() const { return Gr1DKernelEffect::WidthFromRadius(fRadius); } |
| |
| int fRadius; |
| const GrGLShaderVar* fKernelVar; |
| GrGLint fKernelLocation; |
| const GrGLShaderVar* fImageIncrementVar; |
| GrGLint fImageIncrementLocation; |
| |
| typedef GrGLProgramStage INHERITED; |
| }; |
| |
| GrGLConvolutionEffect::GrGLConvolutionEffect(const GrProgramStageFactory& factory, |
| const GrCustomStage& stage) |
| : GrGLProgramStage(factory) |
| , fKernelVar(NULL) |
| , fKernelLocation(0) |
| , fImageIncrementVar(NULL) |
| , fImageIncrementLocation(0) { |
| const GrConvolutionEffect& c = |
| static_cast<const GrConvolutionEffect&>(stage); |
| fRadius = c.radius(); |
| } |
| |
| void GrGLConvolutionEffect::setupVariables(GrGLShaderBuilder* state, |
| int stage) { |
| fImageIncrementVar = &state->addUniform(GrGLShaderBuilder::kFragment_ShaderType | |
| GrGLShaderBuilder::kVertex_ShaderType, |
| kVec2f_GrSLType, "uImageIncrement", stage); |
| fKernelVar = &state->addUniform(GrGLShaderBuilder::kFragment_ShaderType, |
| kFloat_GrSLType, "uKernel", stage, this->width()); |
| |
| fImageIncrementLocation = kUseUniform; |
| fKernelLocation = kUseUniform; |
| } |
| |
| void GrGLConvolutionEffect::emitVS(GrGLShaderBuilder* state, |
| const char* vertexCoords) { |
| SkString* code = &state->fVSCode; |
| code->appendf("\t\t%s -= vec2(%d, %d) * %s;\n", |
| vertexCoords, fRadius, fRadius, |
| fImageIncrementVar->getName().c_str()); |
| } |
| |
| void GrGLConvolutionEffect::emitFS(GrGLShaderBuilder* state, |
| const char* outputColor, |
| const char* inputColor, |
| const char* samplerName) { |
| SkString* code = &state->fFSCode; |
| |
| code->appendf("\t\t%s = vec4(0, 0, 0, 0);\n", outputColor); |
| |
| code->appendf("\t\tvec2 coord = %s;\n", state->fSampleCoords.c_str()); |
| |
| int width = this ->width(); |
| // Manually unroll loop because some drivers don't; yields 20-30% speedup. |
| for (int i = 0; i < width; i++) { |
| SkString index; |
| SkString kernelIndex; |
| index.appendS32(i); |
| fKernelVar->appendArrayAccess(index.c_str(), &kernelIndex); |
| code->appendf("\t\t%s += ", outputColor); |
| state->emitTextureLookup(samplerName, "coord"); |
| code->appendf(" * %s;\n", kernelIndex.c_str()); |
| code->appendf("\t\tcoord += %s;\n", |
| fImageIncrementVar->getName().c_str()); |
| } |
| |
| if (state->fModulate.size()) { |
| code->appendf("\t\t%s = %s%s;\n", outputColor, outputColor, |
| state->fModulate.c_str()); |
| } |
| } |
| |
| void GrGLConvolutionEffect::initUniforms(const GrGLInterface* gl, |
| int programID) { |
| GR_GL_CALL_RET(gl, fImageIncrementLocation, |
| GetUniformLocation(programID, |
| fImageIncrementVar->getName().c_str())); |
| GR_GL_CALL_RET(gl, fKernelLocation, |
| GetUniformLocation(programID, fKernelVar->getName().c_str())); |
| } |
| |
| void GrGLConvolutionEffect::setData(const GrGLInterface* gl, |
| const GrCustomStage& data, |
| const GrRenderTarget*, |
| int stageNum) { |
| const GrConvolutionEffect& conv = |
| static_cast<const GrConvolutionEffect&>(data); |
| GrTexture& texture = *data.texture(0); |
| // the code we generated was for a specific kernel radius |
| GrAssert(conv.radius() == fRadius); |
| float imageIncrement[2] = { 0 }; |
| switch (conv.direction()) { |
| case Gr1DKernelEffect::kX_Direction: |
| imageIncrement[0] = 1.0f / texture.width(); |
| break; |
| case Gr1DKernelEffect::kY_Direction: |
| imageIncrement[1] = 1.0f / texture.height(); |
| break; |
| default: |
| GrCrash("Unknown filter direction."); |
| } |
| GR_GL_CALL(gl, Uniform2fv(fImageIncrementLocation, 1, imageIncrement)); |
| |
| GR_GL_CALL(gl, Uniform1fv(fKernelLocation, this->width(), conv.kernel())); |
| } |
| |
| GrGLProgramStage::StageKey GrGLConvolutionEffect::GenKey( |
| const GrCustomStage& s) { |
| return static_cast<const GrConvolutionEffect&>(s).radius(); |
| } |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| GrConvolutionEffect::GrConvolutionEffect(GrTexture* texture, |
| Direction direction, |
| int radius, |
| const float* kernel) |
| : Gr1DKernelEffect(texture, direction, radius) { |
| GrAssert(radius <= kMaxKernelRadius); |
| int width = this->width(); |
| if (NULL != kernel) { |
| for (int i = 0; i < width; i++) { |
| fKernel[i] = kernel[i]; |
| } |
| } |
| } |
| |
| GrConvolutionEffect::GrConvolutionEffect(GrTexture* texture, |
| Direction direction, |
| int radius, |
| float gaussianSigma) |
| : Gr1DKernelEffect(texture, direction, radius) { |
| GrAssert(radius <= kMaxKernelRadius); |
| int width = this->width(); |
| |
| float sum = 0.0f; |
| float denom = 1.0f / (2.0f * gaussianSigma * gaussianSigma); |
| for (int i = 0; i < width; ++i) { |
| float x = static_cast<float>(i - this->radius()); |
| // Note that the constant term (1/(sqrt(2*pi*sigma^2)) of the Gaussian |
| // is dropped here, since we renormalize the kernel below. |
| fKernel[i] = sk_float_exp(- x * x * denom); |
| sum += fKernel[i]; |
| } |
| // Normalize the kernel |
| float scale = 1.0f / sum; |
| for (int i = 0; i < width; ++i) { |
| fKernel[i] *= scale; |
| } |
| } |
| |
| GrConvolutionEffect::~GrConvolutionEffect() { |
| } |
| |
| const GrProgramStageFactory& GrConvolutionEffect::getFactory() const { |
| return GrTProgramStageFactory<GrConvolutionEffect>::getInstance(); |
| } |
| |
| bool GrConvolutionEffect::isEqual(const GrCustomStage& sBase) const { |
| const GrConvolutionEffect& s = |
| static_cast<const GrConvolutionEffect&>(sBase); |
| return (INHERITED::isEqual(sBase) && |
| this->radius() == s.radius() && |
| this->direction() == s.direction() && |
| 0 == memcmp(fKernel, s.fKernel, this->width() * sizeof(float))); |
| } |
| |