1 /* 2 * Copyright 2012 Google Inc. 3 * 4 * Use of this source code is governed by a BSD-style license that can be 5 * found in the LICENSE file. 6 */ 7 8 #include "GrConvolutionEffect.h" 9 #include "gl/GrGLEffect.h" 10 #include "gl/GrGLEffectMatrix.h" 11 #include "gl/GrGLSL.h" 12 #include "gl/GrGLTexture.h" 13 #include "GrTBackendEffectFactory.h" 14 15 // For brevity 16 typedef GrGLUniformManager::UniformHandle UniformHandle; 17 static const UniformHandle kInvalidUniformHandle = GrGLUniformManager::kInvalidUniformHandle; 18 19 class GrGLConvolutionEffect : public GrGLEffect { 20 public: 21 GrGLConvolutionEffect(const GrBackendEffectFactory&, const GrEffectRef&); 22 23 virtual void emitCode(GrGLShaderBuilder*, 24 const GrEffectStage&, 25 EffectKey, 26 const char* vertexCoords, 27 const char* outputColor, 28 const char* inputColor, 29 const TextureSamplerArray&) SK_OVERRIDE; 30 31 virtual void setData(const GrGLUniformManager& uman, const GrEffectStage&) SK_OVERRIDE; 32 33 static inline EffectKey GenKey(const GrEffectStage&, const GrGLCaps&); 34 35 private: 36 int width() const { return Gr1DKernelEffect::WidthFromRadius(fRadius); } 37 38 int fRadius; 39 UniformHandle fKernelUni; 40 UniformHandle fImageIncrementUni; 41 GrGLEffectMatrix fEffectMatrix; 42 43 typedef GrGLEffect INHERITED; 44 }; 45 46 GrGLConvolutionEffect::GrGLConvolutionEffect(const GrBackendEffectFactory& factory, 47 const GrEffectRef& effect) 48 : INHERITED(factory) 49 , fKernelUni(kInvalidUniformHandle) 50 , fImageIncrementUni(kInvalidUniformHandle) { 51 const GrConvolutionEffect& c = CastEffect<GrConvolutionEffect>(effect); 52 fRadius = c.radius(); 53 } 54 55 void GrGLConvolutionEffect::emitCode(GrGLShaderBuilder* builder, 56 const GrEffectStage&, 57 EffectKey key, 58 const char* vertexCoords, 59 const char* outputColor, 60 const char* inputColor, 61 const TextureSamplerArray& samplers) { 62 const char* coords; 63 fEffectMatrix.emitCodeMakeFSCoords2D(builder, key, vertexCoords, &coords); 64 fImageIncrementUni = builder->addUniform(GrGLShaderBuilder::kFragment_ShaderType, 65 kVec2f_GrSLType, "ImageIncrement"); 66 fKernelUni = builder->addUniformArray(GrGLShaderBuilder::kFragment_ShaderType, 67 kFloat_GrSLType, "Kernel", this->width()); 68 SkString* code = &builder->fFSCode; 69 70 code->appendf("\t\t%s = vec4(0, 0, 0, 0);\n", outputColor); 71 72 int width = this ->width(); 73 const GrGLShaderVar& kernel = builder->getUniformVariable(fKernelUni); 74 const char* imgInc = builder->getUniformCStr(fImageIncrementUni); 75 76 code->appendf("\t\tvec2 coord = %s - %d.0 * %s;\n", coords, fRadius, imgInc); 77 78 // Manually unroll loop because some drivers don't; yields 20-30% speedup. 79 for (int i = 0; i < width; i++) { 80 SkString index; 81 SkString kernelIndex; 82 index.appendS32(i); 83 kernel.appendArrayAccess(index.c_str(), &kernelIndex); 84 code->appendf("\t\t%s += ", outputColor); 85 builder->appendTextureLookup(&builder->fFSCode, samplers[0], "coord"); 86 code->appendf(" * %s;\n", kernelIndex.c_str()); 87 code->appendf("\t\tcoord += %s;\n", imgInc); 88 } 89 GrGLSLMulVarBy4f(&builder->fFSCode, 2, outputColor, inputColor); 90 } 91 92 void GrGLConvolutionEffect::setData(const GrGLUniformManager& uman, const GrEffectStage& stage) { 93 const GrConvolutionEffect& conv = GetEffectFromStage<GrConvolutionEffect>(stage); 94 GrTexture& texture = *conv.texture(0); 95 // the code we generated was for a specific kernel radius 96 GrAssert(conv.radius() == fRadius); 97 float imageIncrement[2] = { 0 }; 98 switch (conv.direction()) { 99 case Gr1DKernelEffect::kX_Direction: 100 imageIncrement[0] = 1.0f / texture.width(); 101 break; 102 case Gr1DKernelEffect::kY_Direction: 103 imageIncrement[1] = 1.0f / texture.height(); 104 break; 105 default: 106 GrCrash("Unknown filter direction."); 107 } 108 uman.set2fv(fImageIncrementUni, 0, 1, imageIncrement); 109 uman.set1fv(fKernelUni, 0, this->width(), conv.kernel()); 110 fEffectMatrix.setData(uman, conv.getMatrix(), stage.getCoordChangeMatrix(), conv.texture(0)); 111 } 112 113 GrGLEffect::EffectKey GrGLConvolutionEffect::GenKey(const GrEffectStage& s, const GrGLCaps&) { 114 const GrConvolutionEffect& conv = GetEffectFromStage<GrConvolutionEffect>(s); 115 EffectKey key = conv.radius(); 116 key <<= GrGLEffectMatrix::kKeyBits; 117 EffectKey matrixKey = GrGLEffectMatrix::GenKey(conv.getMatrix(), 118 s.getCoordChangeMatrix(), 119 conv.texture(0)); 120 return key | matrixKey; 121 } 122 123 /////////////////////////////////////////////////////////////////////////////// 124 125 GrConvolutionEffect::GrConvolutionEffect(GrTexture* texture, 126 Direction direction, 127 int radius, 128 const float* kernel) 129 : Gr1DKernelEffect(texture, direction, radius) { 130 GrAssert(radius <= kMaxKernelRadius); 131 GrAssert(NULL != kernel); 132 int width = this->width(); 133 for (int i = 0; i < width; i++) { 134 fKernel[i] = kernel[i]; 135 } 136 } 137 138 GrConvolutionEffect::GrConvolutionEffect(GrTexture* texture, 139 Direction direction, 140 int radius, 141 float gaussianSigma) 142 : Gr1DKernelEffect(texture, direction, radius) { 143 GrAssert(radius <= kMaxKernelRadius); 144 int width = this->width(); 145 146 float sum = 0.0f; 147 float denom = 1.0f / (2.0f * gaussianSigma * gaussianSigma); 148 for (int i = 0; i < width; ++i) { 149 float x = static_cast<float>(i - this->radius()); 150 // Note that the constant term (1/(sqrt(2*pi*sigma^2)) of the Gaussian 151 // is dropped here, since we renormalize the kernel below. 152 fKernel[i] = sk_float_exp(- x * x * denom); 153 sum += fKernel[i]; 154 } 155 // Normalize the kernel 156 float scale = 1.0f / sum; 157 for (int i = 0; i < width; ++i) { 158 fKernel[i] *= scale; 159 } 160 } 161 162 GrConvolutionEffect::~GrConvolutionEffect() { 163 } 164 165 const GrBackendEffectFactory& GrConvolutionEffect::getFactory() const { 166 return GrTBackendEffectFactory<GrConvolutionEffect>::getInstance(); 167 } 168 169 bool GrConvolutionEffect::onIsEqual(const GrEffect& sBase) const { 170 const GrConvolutionEffect& s = CastEffect<GrConvolutionEffect>(sBase); 171 return (this->texture(0) == s.texture(0) && 172 this->radius() == s.radius() && 173 this->direction() == s.direction() && 174 0 == memcmp(fKernel, s.fKernel, this->width() * sizeof(float))); 175 } 176 177 /////////////////////////////////////////////////////////////////////////////// 178 179 GR_DEFINE_EFFECT_TEST(GrConvolutionEffect); 180 181 GrEffectRef* GrConvolutionEffect::TestCreate(SkRandom* random, 182 GrContext* context, 183 GrTexture* textures[]) { 184 int texIdx = random->nextBool() ? GrEffectUnitTest::kSkiaPMTextureIdx : 185 GrEffectUnitTest::kAlphaTextureIdx; 186 Direction dir = random->nextBool() ? kX_Direction : kY_Direction; 187 int radius = random->nextRangeU(1, kMaxKernelRadius); 188 float kernel[kMaxKernelRadius]; 189 for (int i = 0; i < kMaxKernelRadius; ++i) { 190 kernel[i] = random->nextSScalar1(); 191 } 192 193 return GrConvolutionEffect::Create(textures[texIdx], dir, radius,kernel); 194 } 195
