GrCircleBlurFragmentProcessor.cpp revision ceb4d48ef4839aab9d99d0200dcfe403ccd0cdf3
1/* 2 * Copyright 2017 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/* 9 * This file was autogenerated from GrCircleBlurFragmentProcessor.fp; do not modify. 10 */ 11#include "GrCircleBlurFragmentProcessor.h" 12#if SK_SUPPORT_GPU 13 14 #include "GrResourceProvider.h" 15 16 17 18 static float make_unnormalized_half_kernel(float* halfKernel, int halfKernelSize, float sigma) { 19 const float invSigma = 1.f / sigma; 20 const float b = -0.5f * invSigma * invSigma; 21 float tot = 0.0f; 22 23 float t = 0.5f; 24 for (int i = 0; i < halfKernelSize; ++i) { 25 float value = expf(t * t * b); 26 tot += value; 27 halfKernel[i] = value; 28 t += 1.f; 29 } 30 return tot; 31 } 32 33 34 35 static void make_half_kernel_and_summed_table(float* halfKernel, float* summedHalfKernel, 36 int halfKernelSize, float sigma) { 37 38 const float tot = 2.f * make_unnormalized_half_kernel(halfKernel, halfKernelSize, sigma); 39 float sum = 0.f; 40 for (int i = 0; i < halfKernelSize; ++i) { 41 halfKernel[i] /= tot; 42 sum += halfKernel[i]; 43 summedHalfKernel[i] = sum; 44 } 45 } 46 47 48 49 void apply_kernel_in_y(float* results, int numSteps, float firstX, float circleR, 50 int halfKernelSize, const float* summedHalfKernelTable) { 51 float x = firstX; 52 for (int i = 0; i < numSteps; ++i, x += 1.f) { 53 if (x < -circleR || x > circleR) { 54 results[i] = 0; 55 continue; 56 } 57 float y = sqrtf(circleR * circleR - x * x); 58 59 60 y -= 0.5f; 61 int yInt = SkScalarFloorToInt(y); 62 SkASSERT(yInt >= -1); 63 if (y < 0) { 64 results[i] = (y + 0.5f) * summedHalfKernelTable[0]; 65 } else if (yInt >= halfKernelSize - 1) { 66 results[i] = 0.5f; 67 } else { 68 float yFrac = y - yInt; 69 results[i] = (1.f - yFrac) * summedHalfKernelTable[yInt] + 70 yFrac * summedHalfKernelTable[yInt + 1]; 71 } 72 } 73 } 74 75 76 77 78 79 static uint8_t eval_at(float evalX, float circleR, const float* halfKernel, int halfKernelSize, 80 const float* yKernelEvaluations) { 81 float acc = 0; 82 83 float x = evalX - halfKernelSize; 84 for (int i = 0; i < halfKernelSize; ++i, x += 1.f) { 85 if (x < -circleR || x > circleR) { 86 continue; 87 } 88 float verticalEval = yKernelEvaluations[i]; 89 acc += verticalEval * halfKernel[halfKernelSize - i - 1]; 90 } 91 for (int i = 0; i < halfKernelSize; ++i, x += 1.f) { 92 if (x < -circleR || x > circleR) { 93 continue; 94 } 95 float verticalEval = yKernelEvaluations[i + halfKernelSize]; 96 acc += verticalEval * halfKernel[i]; 97 } 98 99 100 return SkUnitScalarClampToByte(2.f * acc); 101 } 102 103 104 105 106 107 108 109 110 static uint8_t* create_circle_profile(float sigma, float circleR, int profileTextureWidth) { 111 const int numSteps = profileTextureWidth; 112 uint8_t* weights = new uint8_t[numSteps]; 113 114 115 int halfKernelSize = SkScalarCeilToInt(6.0f*sigma); 116 117 halfKernelSize = ((halfKernelSize + 1) & ~1) >> 1; 118 119 120 int numYSteps = numSteps + 2 * halfKernelSize; 121 122 SkAutoTArray<float> bulkAlloc(halfKernelSize + halfKernelSize + numYSteps); 123 float* halfKernel = bulkAlloc.get(); 124 float* summedKernel = bulkAlloc.get() + halfKernelSize; 125 float* yEvals = bulkAlloc.get() + 2 * halfKernelSize; 126 make_half_kernel_and_summed_table(halfKernel, summedKernel, halfKernelSize, sigma); 127 128 float firstX = -halfKernelSize + 0.5f; 129 apply_kernel_in_y(yEvals, numYSteps, firstX, circleR, halfKernelSize, summedKernel); 130 131 for (int i = 0; i < numSteps - 1; ++i) { 132 float evalX = i + 0.5f; 133 weights[i] = eval_at(evalX, circleR, halfKernel, halfKernelSize, yEvals + i); 134 } 135 136 weights[numSteps - 1] = 0; 137 return weights; 138 } 139 140 static uint8_t* create_half_plane_profile(int profileWidth) { 141 SkASSERT(!(profileWidth & 0x1)); 142 143 float sigma = profileWidth / 6.f; 144 int halfKernelSize = profileWidth / 2; 145 146 SkAutoTArray<float> halfKernel(halfKernelSize); 147 uint8_t* profile = new uint8_t[profileWidth]; 148 149 150 const float tot = 2.f * make_unnormalized_half_kernel(halfKernel.get(), halfKernelSize, 151 sigma); 152 float sum = 0.f; 153 154 for (int i = 0; i < halfKernelSize; ++i) { 155 halfKernel[halfKernelSize - i - 1] /= tot; 156 sum += halfKernel[halfKernelSize - i - 1]; 157 profile[profileWidth - i - 1] = SkUnitScalarClampToByte(sum); 158 } 159 160 161 for (int i = 0; i < halfKernelSize; ++i) { 162 sum += halfKernel[i]; 163 profile[halfKernelSize - i - 1] = SkUnitScalarClampToByte(sum); 164 } 165 166 profile[profileWidth - 1] = 0; 167 return profile; 168 } 169 170 static sk_sp<GrTextureProxy> create_profile_texture(GrResourceProvider* resourceProvider, 171 const SkRect& circle, 172 float sigma, 173 float* solidRadius, float* textureRadius) { 174 float circleR = circle.width() / 2.0f; 175 176 177 SkScalar sigmaToCircleRRatio = sigma / circleR; 178 179 180 181 182 sigmaToCircleRRatio = SkTMin(sigmaToCircleRRatio, 8.f); 183 SkFixed sigmaToCircleRRatioFixed; 184 static const SkScalar kHalfPlaneThreshold = 0.1f; 185 bool useHalfPlaneApprox = false; 186 if (sigmaToCircleRRatio <= kHalfPlaneThreshold) { 187 useHalfPlaneApprox = true; 188 sigmaToCircleRRatioFixed = 0; 189 *solidRadius = circleR - 3 * sigma; 190 *textureRadius = 6 * sigma; 191 } else { 192 193 sigmaToCircleRRatioFixed = SkScalarToFixed(sigmaToCircleRRatio); 194 195 196 sigmaToCircleRRatioFixed &= ~0xff; 197 sigmaToCircleRRatio = SkFixedToScalar(sigmaToCircleRRatioFixed); 198 sigma = circleR * sigmaToCircleRRatio; 199 *solidRadius = 0; 200 *textureRadius = circleR + 3 * sigma; 201 } 202 203 static const GrUniqueKey::Domain kDomain = GrUniqueKey::GenerateDomain(); 204 GrUniqueKey key; 205 GrUniqueKey::Builder builder(&key, kDomain, 1); 206 builder[0] = sigmaToCircleRRatioFixed; 207 builder.finish(); 208 209 sk_sp<GrTextureProxy> blurProfile = resourceProvider->findProxyByUniqueKey(key); 210 if (!blurProfile) { 211 static constexpr int kProfileTextureWidth = 512; 212 GrSurfaceDesc texDesc; 213 texDesc.fWidth = kProfileTextureWidth; 214 texDesc.fHeight = 1; 215 texDesc.fConfig = kAlpha_8_GrPixelConfig; 216 217 std::unique_ptr<uint8_t[]> profile(nullptr); 218 if (useHalfPlaneApprox) { 219 profile.reset(create_half_plane_profile(kProfileTextureWidth)); 220 } else { 221 222 SkScalar scale = kProfileTextureWidth / *textureRadius; 223 profile.reset(create_circle_profile(sigma * scale, circleR * scale, 224 kProfileTextureWidth)); 225 } 226 227 blurProfile = GrSurfaceProxy::MakeDeferred(resourceProvider, 228 texDesc, SkBudgeted::kYes, profile.get(), 0); 229 if (!blurProfile) { 230 return nullptr; 231 } 232 233 resourceProvider->assignUniqueKeyToProxy(key, blurProfile.get()); 234 } 235 236 return blurProfile; 237 } 238 239 sk_sp<GrFragmentProcessor> GrCircleBlurFragmentProcessor::Make( 240 GrResourceProvider* resourceProvider, 241 const SkRect& circle, 242 float sigma) { 243 float solidRadius; 244 float textureRadius; 245 sk_sp<GrTextureProxy> profile(create_profile_texture(resourceProvider, circle, sigma, 246 &solidRadius, &textureRadius)); 247 if (!profile) { 248 return nullptr; 249 } 250 return sk_sp<GrFragmentProcessor>(new GrCircleBlurFragmentProcessor(circle, 251 textureRadius, 252 solidRadius, 253 std::move(profile), 254 resourceProvider)); 255 } 256#include "glsl/GrGLSLColorSpaceXformHelper.h" 257#include "glsl/GrGLSLFragmentProcessor.h" 258#include "glsl/GrGLSLFragmentShaderBuilder.h" 259#include "glsl/GrGLSLProgramBuilder.h" 260#include "SkSLCPP.h" 261#include "SkSLUtil.h" 262class GrGLSLCircleBlurFragmentProcessor : public GrGLSLFragmentProcessor { 263public: 264 GrGLSLCircleBlurFragmentProcessor() {} 265 void emitCode(EmitArgs& args) override { 266 GrGLSLFPFragmentBuilder* fragBuilder = args.fFragBuilder; 267 const GrCircleBlurFragmentProcessor& _outer = args.fFp.cast<GrCircleBlurFragmentProcessor>(); 268 (void) _outer; 269 fCircleDataVar = args.fUniformHandler->addUniform(kFragment_GrShaderFlag, kVec4f_GrSLType, kDefault_GrSLPrecision, "circleData"); 270 fragBuilder->codeAppendf("vec2 vec = vec2((sk_FragCoord.x - %s.x) * %s.w, (sk_FragCoord.y - %s.y) * %s.w);\nfloat dist = length(vec) + (0.5 - %s.z) * %s.w;\n%s = %s * texture(%s, vec2(dist, 0.5)).%s.w;\n", args.fUniformHandler->getUniformCStr(fCircleDataVar), args.fUniformHandler->getUniformCStr(fCircleDataVar), args.fUniformHandler->getUniformCStr(fCircleDataVar), args.fUniformHandler->getUniformCStr(fCircleDataVar), args.fUniformHandler->getUniformCStr(fCircleDataVar), args.fUniformHandler->getUniformCStr(fCircleDataVar), args.fOutputColor, args.fInputColor ? args.fInputColor : "vec4(1)", fragBuilder->getProgramBuilder()->samplerVariable(args.fTexSamplers[0]).c_str(), fragBuilder->getProgramBuilder()->samplerSwizzle(args.fTexSamplers[0]).c_str()); 271 } 272private: 273 void onSetData(const GrGLSLProgramDataManager& data, const GrFragmentProcessor& _proc) override { 274 const GrCircleBlurFragmentProcessor& _outer = _proc.cast<GrCircleBlurFragmentProcessor>(); 275 auto circleRect = _outer.circleRect(); 276 (void) circleRect; 277 auto textureRadius = _outer.textureRadius(); 278 (void) textureRadius; 279 auto solidRadius = _outer.solidRadius(); 280 (void) solidRadius; 281 UniformHandle& blurProfileSampler = fBlurProfileSamplerVar; 282 (void) blurProfileSampler; 283 UniformHandle& circleData = fCircleDataVar; 284 (void) circleData; 285 286 data.set4f(circleData, circleRect.centerX(), circleRect.centerY(), solidRadius, 287 1.f / textureRadius); 288 } 289 UniformHandle fCircleDataVar; 290 UniformHandle fBlurProfileSamplerVar; 291}; 292GrGLSLFragmentProcessor* GrCircleBlurFragmentProcessor::onCreateGLSLInstance() const { 293 return new GrGLSLCircleBlurFragmentProcessor(); 294} 295void GrCircleBlurFragmentProcessor::onGetGLSLProcessorKey(const GrShaderCaps& caps, GrProcessorKeyBuilder* b) const { 296} 297bool GrCircleBlurFragmentProcessor::onIsEqual(const GrFragmentProcessor& other) const { 298 const GrCircleBlurFragmentProcessor& that = other.cast<GrCircleBlurFragmentProcessor>(); 299 (void) that; 300 if (fCircleRect != that.fCircleRect) return false; 301 if (fTextureRadius != that.fTextureRadius) return false; 302 if (fSolidRadius != that.fSolidRadius) return false; 303 if (fBlurProfileSampler != that.fBlurProfileSampler) return false; 304 return true; 305} 306GR_DEFINE_FRAGMENT_PROCESSOR_TEST(GrCircleBlurFragmentProcessor); 307#if GR_TEST_UTILS 308sk_sp<GrFragmentProcessor> GrCircleBlurFragmentProcessor::TestCreate(GrProcessorTestData* testData) { 309 310 SkScalar wh = testData->fRandom->nextRangeScalar(100.f, 1000.f); 311 SkScalar sigma = testData->fRandom->nextRangeF(1.f,10.f); 312 SkRect circle = SkRect::MakeWH(wh, wh); 313 return GrCircleBlurFragmentProcessor::Make(testData->resourceProvider(), circle, sigma); 314} 315#endif 316#endif 317