1 /* 2 * Copyright 2013 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 "SkPerlinNoiseShader.h" 9 #include "SkColorFilter.h" 10 #include "SkReadBuffer.h" 11 #include "SkWriteBuffer.h" 12 #include "SkShader.h" 13 #include "SkUnPreMultiply.h" 14 #include "SkString.h" 15 16 #if SK_SUPPORT_GPU 17 #include "GrContext.h" 18 #include "GrCoordTransform.h" 19 #include "GrInvariantOutput.h" 20 #include "SkGr.h" 21 #include "effects/GrConstColorProcessor.h" 22 #include "glsl/GrGLSLFragmentProcessor.h" 23 #include "glsl/GrGLSLFragmentShaderBuilder.h" 24 #include "glsl/GrGLSLProgramDataManager.h" 25 #include "glsl/GrGLSLUniformHandler.h" 26 #endif 27 28 static const int kBlockSize = 256; 29 static const int kBlockMask = kBlockSize - 1; 30 static const int kPerlinNoise = 4096; 31 static const int kRandMaximum = SK_MaxS32; // 2**31 - 1 32 33 namespace { 34 35 // noiseValue is the color component's value (or color) 36 // limitValue is the maximum perlin noise array index value allowed 37 // newValue is the current noise dimension (either width or height) 38 inline int checkNoise(int noiseValue, int limitValue, int newValue) { 39 // If the noise value would bring us out of bounds of the current noise array while we are 40 // stiching noise tiles together, wrap the noise around the current dimension of the noise to 41 // stay within the array bounds in a continuous fashion (so that tiling lines are not visible) 42 if (noiseValue >= limitValue) { 43 noiseValue -= newValue; 44 } 45 return noiseValue; 46 } 47 48 inline SkScalar smoothCurve(SkScalar t) { 49 static const SkScalar SK_Scalar3 = 3.0f; 50 51 // returns t * t * (3 - 2 * t) 52 return SkScalarMul(SkScalarSquare(t), SK_Scalar3 - 2 * t); 53 } 54 55 } // end namespace 56 57 struct SkPerlinNoiseShader::StitchData { 58 StitchData() 59 : fWidth(0) 60 , fWrapX(0) 61 , fHeight(0) 62 , fWrapY(0) 63 {} 64 65 bool operator==(const StitchData& other) const { 66 return fWidth == other.fWidth && 67 fWrapX == other.fWrapX && 68 fHeight == other.fHeight && 69 fWrapY == other.fWrapY; 70 } 71 72 int fWidth; // How much to subtract to wrap for stitching. 73 int fWrapX; // Minimum value to wrap. 74 int fHeight; 75 int fWrapY; 76 }; 77 78 struct SkPerlinNoiseShader::PaintingData { 79 PaintingData(const SkISize& tileSize, SkScalar seed, 80 SkScalar baseFrequencyX, SkScalar baseFrequencyY, 81 const SkMatrix& matrix) 82 { 83 SkVector vec[2] = { 84 { SkScalarInvert(baseFrequencyX), SkScalarInvert(baseFrequencyY) }, 85 { SkIntToScalar(tileSize.fWidth), SkIntToScalar(tileSize.fHeight) }, 86 }; 87 matrix.mapVectors(vec, 2); 88 89 fBaseFrequency.set(SkScalarInvert(vec[0].fX), SkScalarInvert(vec[0].fY)); 90 fTileSize.set(SkScalarRoundToInt(vec[1].fX), SkScalarRoundToInt(vec[1].fY)); 91 this->init(seed); 92 if (!fTileSize.isEmpty()) { 93 this->stitch(); 94 } 95 96 #if SK_SUPPORT_GPU 97 fPermutationsBitmap.setInfo(SkImageInfo::MakeA8(kBlockSize, 1)); 98 fPermutationsBitmap.setPixels(fLatticeSelector); 99 100 fNoiseBitmap.setInfo(SkImageInfo::MakeN32Premul(kBlockSize, 4)); 101 fNoiseBitmap.setPixels(fNoise[0][0]); 102 #endif 103 } 104 105 int fSeed; 106 uint8_t fLatticeSelector[kBlockSize]; 107 uint16_t fNoise[4][kBlockSize][2]; 108 SkPoint fGradient[4][kBlockSize]; 109 SkISize fTileSize; 110 SkVector fBaseFrequency; 111 StitchData fStitchDataInit; 112 113 private: 114 115 #if SK_SUPPORT_GPU 116 SkBitmap fPermutationsBitmap; 117 SkBitmap fNoiseBitmap; 118 #endif 119 120 inline int random() { 121 static const int gRandAmplitude = 16807; // 7**5; primitive root of m 122 static const int gRandQ = 127773; // m / a 123 static const int gRandR = 2836; // m % a 124 125 int result = gRandAmplitude * (fSeed % gRandQ) - gRandR * (fSeed / gRandQ); 126 if (result <= 0) 127 result += kRandMaximum; 128 fSeed = result; 129 return result; 130 } 131 132 // Only called once. Could be part of the constructor. 133 void init(SkScalar seed) 134 { 135 static const SkScalar gInvBlockSizef = SkScalarInvert(SkIntToScalar(kBlockSize)); 136 137 // According to the SVG spec, we must truncate (not round) the seed value. 138 fSeed = SkScalarTruncToInt(seed); 139 // The seed value clamp to the range [1, kRandMaximum - 1]. 140 if (fSeed <= 0) { 141 fSeed = -(fSeed % (kRandMaximum - 1)) + 1; 142 } 143 if (fSeed > kRandMaximum - 1) { 144 fSeed = kRandMaximum - 1; 145 } 146 for (int channel = 0; channel < 4; ++channel) { 147 for (int i = 0; i < kBlockSize; ++i) { 148 fLatticeSelector[i] = i; 149 fNoise[channel][i][0] = (random() % (2 * kBlockSize)); 150 fNoise[channel][i][1] = (random() % (2 * kBlockSize)); 151 } 152 } 153 for (int i = kBlockSize - 1; i > 0; --i) { 154 int k = fLatticeSelector[i]; 155 int j = random() % kBlockSize; 156 SkASSERT(j >= 0); 157 SkASSERT(j < kBlockSize); 158 fLatticeSelector[i] = fLatticeSelector[j]; 159 fLatticeSelector[j] = k; 160 } 161 162 // Perform the permutations now 163 { 164 // Copy noise data 165 uint16_t noise[4][kBlockSize][2]; 166 for (int i = 0; i < kBlockSize; ++i) { 167 for (int channel = 0; channel < 4; ++channel) { 168 for (int j = 0; j < 2; ++j) { 169 noise[channel][i][j] = fNoise[channel][i][j]; 170 } 171 } 172 } 173 // Do permutations on noise data 174 for (int i = 0; i < kBlockSize; ++i) { 175 for (int channel = 0; channel < 4; ++channel) { 176 for (int j = 0; j < 2; ++j) { 177 fNoise[channel][i][j] = noise[channel][fLatticeSelector[i]][j]; 178 } 179 } 180 } 181 } 182 183 // Half of the largest possible value for 16 bit unsigned int 184 static const SkScalar gHalfMax16bits = 32767.5f; 185 186 // Compute gradients from permutated noise data 187 for (int channel = 0; channel < 4; ++channel) { 188 for (int i = 0; i < kBlockSize; ++i) { 189 fGradient[channel][i] = SkPoint::Make( 190 SkScalarMul(SkIntToScalar(fNoise[channel][i][0] - kBlockSize), 191 gInvBlockSizef), 192 SkScalarMul(SkIntToScalar(fNoise[channel][i][1] - kBlockSize), 193 gInvBlockSizef)); 194 fGradient[channel][i].normalize(); 195 // Put the normalized gradient back into the noise data 196 fNoise[channel][i][0] = SkScalarRoundToInt(SkScalarMul( 197 fGradient[channel][i].fX + SK_Scalar1, gHalfMax16bits)); 198 fNoise[channel][i][1] = SkScalarRoundToInt(SkScalarMul( 199 fGradient[channel][i].fY + SK_Scalar1, gHalfMax16bits)); 200 } 201 } 202 } 203 204 // Only called once. Could be part of the constructor. 205 void stitch() { 206 SkScalar tileWidth = SkIntToScalar(fTileSize.width()); 207 SkScalar tileHeight = SkIntToScalar(fTileSize.height()); 208 SkASSERT(tileWidth > 0 && tileHeight > 0); 209 // When stitching tiled turbulence, the frequencies must be adjusted 210 // so that the tile borders will be continuous. 211 if (fBaseFrequency.fX) { 212 SkScalar lowFrequencx = 213 SkScalarFloorToScalar(tileWidth * fBaseFrequency.fX) / tileWidth; 214 SkScalar highFrequencx = 215 SkScalarCeilToScalar(tileWidth * fBaseFrequency.fX) / tileWidth; 216 // BaseFrequency should be non-negative according to the standard. 217 if (fBaseFrequency.fX / lowFrequencx < highFrequencx / fBaseFrequency.fX) { 218 fBaseFrequency.fX = lowFrequencx; 219 } else { 220 fBaseFrequency.fX = highFrequencx; 221 } 222 } 223 if (fBaseFrequency.fY) { 224 SkScalar lowFrequency = 225 SkScalarFloorToScalar(tileHeight * fBaseFrequency.fY) / tileHeight; 226 SkScalar highFrequency = 227 SkScalarCeilToScalar(tileHeight * fBaseFrequency.fY) / tileHeight; 228 if (fBaseFrequency.fY / lowFrequency < highFrequency / fBaseFrequency.fY) { 229 fBaseFrequency.fY = lowFrequency; 230 } else { 231 fBaseFrequency.fY = highFrequency; 232 } 233 } 234 // Set up TurbulenceInitial stitch values. 235 fStitchDataInit.fWidth = 236 SkScalarRoundToInt(tileWidth * fBaseFrequency.fX); 237 fStitchDataInit.fWrapX = kPerlinNoise + fStitchDataInit.fWidth; 238 fStitchDataInit.fHeight = 239 SkScalarRoundToInt(tileHeight * fBaseFrequency.fY); 240 fStitchDataInit.fWrapY = kPerlinNoise + fStitchDataInit.fHeight; 241 } 242 243 public: 244 245 #if SK_SUPPORT_GPU 246 const SkBitmap& getPermutationsBitmap() const { return fPermutationsBitmap; } 247 248 const SkBitmap& getNoiseBitmap() const { return fNoiseBitmap; } 249 #endif 250 }; 251 252 SkShader* SkPerlinNoiseShader::CreateFractalNoise(SkScalar baseFrequencyX, SkScalar baseFrequencyY, 253 int numOctaves, SkScalar seed, 254 const SkISize* tileSize) { 255 return new SkPerlinNoiseShader(kFractalNoise_Type, baseFrequencyX, baseFrequencyY, numOctaves, 256 seed, tileSize); 257 } 258 259 SkShader* SkPerlinNoiseShader::CreateTurbulence(SkScalar baseFrequencyX, SkScalar baseFrequencyY, 260 int numOctaves, SkScalar seed, 261 const SkISize* tileSize) { 262 return new SkPerlinNoiseShader(kTurbulence_Type, baseFrequencyX, baseFrequencyY, numOctaves, 263 seed, tileSize); 264 } 265 266 SkPerlinNoiseShader::SkPerlinNoiseShader(SkPerlinNoiseShader::Type type, 267 SkScalar baseFrequencyX, 268 SkScalar baseFrequencyY, 269 int numOctaves, 270 SkScalar seed, 271 const SkISize* tileSize) 272 : fType(type) 273 , fBaseFrequencyX(baseFrequencyX) 274 , fBaseFrequencyY(baseFrequencyY) 275 , fNumOctaves(numOctaves > 255 ? 255 : numOctaves/*[0,255] octaves allowed*/) 276 , fSeed(seed) 277 , fTileSize(nullptr == tileSize ? SkISize::Make(0, 0) : *tileSize) 278 , fStitchTiles(!fTileSize.isEmpty()) 279 { 280 SkASSERT(numOctaves >= 0 && numOctaves < 256); 281 } 282 283 SkPerlinNoiseShader::~SkPerlinNoiseShader() { 284 } 285 286 SkFlattenable* SkPerlinNoiseShader::CreateProc(SkReadBuffer& buffer) { 287 Type type = (Type)buffer.readInt(); 288 SkScalar freqX = buffer.readScalar(); 289 SkScalar freqY = buffer.readScalar(); 290 int octaves = buffer.readInt(); 291 SkScalar seed = buffer.readScalar(); 292 SkISize tileSize; 293 tileSize.fWidth = buffer.readInt(); 294 tileSize.fHeight = buffer.readInt(); 295 296 switch (type) { 297 case kFractalNoise_Type: 298 return SkPerlinNoiseShader::CreateFractalNoise(freqX, freqY, octaves, seed, &tileSize); 299 case kTurbulence_Type: 300 return SkPerlinNoiseShader::CreateTubulence(freqX, freqY, octaves, seed, &tileSize); 301 default: 302 return nullptr; 303 } 304 } 305 306 void SkPerlinNoiseShader::flatten(SkWriteBuffer& buffer) const { 307 buffer.writeInt((int) fType); 308 buffer.writeScalar(fBaseFrequencyX); 309 buffer.writeScalar(fBaseFrequencyY); 310 buffer.writeInt(fNumOctaves); 311 buffer.writeScalar(fSeed); 312 buffer.writeInt(fTileSize.fWidth); 313 buffer.writeInt(fTileSize.fHeight); 314 } 315 316 SkScalar SkPerlinNoiseShader::PerlinNoiseShaderContext::noise2D( 317 int channel, const StitchData& stitchData, const SkPoint& noiseVector) const { 318 struct Noise { 319 int noisePositionIntegerValue; 320 int nextNoisePositionIntegerValue; 321 SkScalar noisePositionFractionValue; 322 Noise(SkScalar component) 323 { 324 SkScalar position = component + kPerlinNoise; 325 noisePositionIntegerValue = SkScalarFloorToInt(position); 326 noisePositionFractionValue = position - SkIntToScalar(noisePositionIntegerValue); 327 nextNoisePositionIntegerValue = noisePositionIntegerValue + 1; 328 } 329 }; 330 Noise noiseX(noiseVector.x()); 331 Noise noiseY(noiseVector.y()); 332 SkScalar u, v; 333 const SkPerlinNoiseShader& perlinNoiseShader = static_cast<const SkPerlinNoiseShader&>(fShader); 334 // If stitching, adjust lattice points accordingly. 335 if (perlinNoiseShader.fStitchTiles) { 336 noiseX.noisePositionIntegerValue = 337 checkNoise(noiseX.noisePositionIntegerValue, stitchData.fWrapX, stitchData.fWidth); 338 noiseY.noisePositionIntegerValue = 339 checkNoise(noiseY.noisePositionIntegerValue, stitchData.fWrapY, stitchData.fHeight); 340 noiseX.nextNoisePositionIntegerValue = 341 checkNoise(noiseX.nextNoisePositionIntegerValue, stitchData.fWrapX, stitchData.fWidth); 342 noiseY.nextNoisePositionIntegerValue = 343 checkNoise(noiseY.nextNoisePositionIntegerValue, stitchData.fWrapY, stitchData.fHeight); 344 } 345 noiseX.noisePositionIntegerValue &= kBlockMask; 346 noiseY.noisePositionIntegerValue &= kBlockMask; 347 noiseX.nextNoisePositionIntegerValue &= kBlockMask; 348 noiseY.nextNoisePositionIntegerValue &= kBlockMask; 349 int i = 350 fPaintingData->fLatticeSelector[noiseX.noisePositionIntegerValue]; 351 int j = 352 fPaintingData->fLatticeSelector[noiseX.nextNoisePositionIntegerValue]; 353 int b00 = (i + noiseY.noisePositionIntegerValue) & kBlockMask; 354 int b10 = (j + noiseY.noisePositionIntegerValue) & kBlockMask; 355 int b01 = (i + noiseY.nextNoisePositionIntegerValue) & kBlockMask; 356 int b11 = (j + noiseY.nextNoisePositionIntegerValue) & kBlockMask; 357 SkScalar sx = smoothCurve(noiseX.noisePositionFractionValue); 358 SkScalar sy = smoothCurve(noiseY.noisePositionFractionValue); 359 // This is taken 1:1 from SVG spec: http://www.w3.org/TR/SVG11/filters.html#feTurbulenceElement 360 SkPoint fractionValue = SkPoint::Make(noiseX.noisePositionFractionValue, 361 noiseY.noisePositionFractionValue); // Offset (0,0) 362 u = fPaintingData->fGradient[channel][b00].dot(fractionValue); 363 fractionValue.fX -= SK_Scalar1; // Offset (-1,0) 364 v = fPaintingData->fGradient[channel][b10].dot(fractionValue); 365 SkScalar a = SkScalarInterp(u, v, sx); 366 fractionValue.fY -= SK_Scalar1; // Offset (-1,-1) 367 v = fPaintingData->fGradient[channel][b11].dot(fractionValue); 368 fractionValue.fX = noiseX.noisePositionFractionValue; // Offset (0,-1) 369 u = fPaintingData->fGradient[channel][b01].dot(fractionValue); 370 SkScalar b = SkScalarInterp(u, v, sx); 371 return SkScalarInterp(a, b, sy); 372 } 373 374 SkScalar SkPerlinNoiseShader::PerlinNoiseShaderContext::calculateTurbulenceValueForPoint( 375 int channel, StitchData& stitchData, const SkPoint& point) const { 376 const SkPerlinNoiseShader& perlinNoiseShader = static_cast<const SkPerlinNoiseShader&>(fShader); 377 if (perlinNoiseShader.fStitchTiles) { 378 // Set up TurbulenceInitial stitch values. 379 stitchData = fPaintingData->fStitchDataInit; 380 } 381 SkScalar turbulenceFunctionResult = 0; 382 SkPoint noiseVector(SkPoint::Make(SkScalarMul(point.x(), fPaintingData->fBaseFrequency.fX), 383 SkScalarMul(point.y(), fPaintingData->fBaseFrequency.fY))); 384 SkScalar ratio = SK_Scalar1; 385 for (int octave = 0; octave < perlinNoiseShader.fNumOctaves; ++octave) { 386 SkScalar noise = noise2D(channel, stitchData, noiseVector); 387 SkScalar numer = (perlinNoiseShader.fType == kFractalNoise_Type) ? 388 noise : SkScalarAbs(noise); 389 turbulenceFunctionResult += numer / ratio; 390 noiseVector.fX *= 2; 391 noiseVector.fY *= 2; 392 ratio *= 2; 393 if (perlinNoiseShader.fStitchTiles) { 394 // Update stitch values 395 stitchData.fWidth *= 2; 396 stitchData.fWrapX = stitchData.fWidth + kPerlinNoise; 397 stitchData.fHeight *= 2; 398 stitchData.fWrapY = stitchData.fHeight + kPerlinNoise; 399 } 400 } 401 402 // The value of turbulenceFunctionResult comes from ((turbulenceFunctionResult) + 1) / 2 403 // by fractalNoise and (turbulenceFunctionResult) by turbulence. 404 if (perlinNoiseShader.fType == kFractalNoise_Type) { 405 turbulenceFunctionResult = 406 SkScalarMul(turbulenceFunctionResult, SK_ScalarHalf) + SK_ScalarHalf; 407 } 408 409 if (channel == 3) { // Scale alpha by paint value 410 turbulenceFunctionResult *= SkIntToScalar(getPaintAlpha()) / 255; 411 } 412 413 // Clamp result 414 return SkScalarPin(turbulenceFunctionResult, 0, SK_Scalar1); 415 } 416 417 SkPMColor SkPerlinNoiseShader::PerlinNoiseShaderContext::shade( 418 const SkPoint& point, StitchData& stitchData) const { 419 SkPoint newPoint; 420 fMatrix.mapPoints(&newPoint, &point, 1); 421 newPoint.fX = SkScalarRoundToScalar(newPoint.fX); 422 newPoint.fY = SkScalarRoundToScalar(newPoint.fY); 423 424 U8CPU rgba[4]; 425 for (int channel = 3; channel >= 0; --channel) { 426 rgba[channel] = SkScalarFloorToInt(255 * 427 calculateTurbulenceValueForPoint(channel, stitchData, newPoint)); 428 } 429 return SkPreMultiplyARGB(rgba[3], rgba[0], rgba[1], rgba[2]); 430 } 431 432 SkShader::Context* SkPerlinNoiseShader::onCreateContext(const ContextRec& rec, 433 void* storage) const { 434 return new (storage) PerlinNoiseShaderContext(*this, rec); 435 } 436 437 size_t SkPerlinNoiseShader::contextSize(const ContextRec&) const { 438 return sizeof(PerlinNoiseShaderContext); 439 } 440 441 SkPerlinNoiseShader::PerlinNoiseShaderContext::PerlinNoiseShaderContext( 442 const SkPerlinNoiseShader& shader, const ContextRec& rec) 443 : INHERITED(shader, rec) 444 { 445 SkMatrix newMatrix = *rec.fMatrix; 446 newMatrix.preConcat(shader.getLocalMatrix()); 447 if (rec.fLocalMatrix) { 448 newMatrix.preConcat(*rec.fLocalMatrix); 449 } 450 // This (1,1) translation is due to WebKit's 1 based coordinates for the noise 451 // (as opposed to 0 based, usually). The same adjustment is in the setData() function. 452 fMatrix.setTranslate(-newMatrix.getTranslateX() + SK_Scalar1, -newMatrix.getTranslateY() + SK_Scalar1); 453 fPaintingData = new PaintingData(shader.fTileSize, shader.fSeed, shader.fBaseFrequencyX, 454 shader.fBaseFrequencyY, newMatrix); 455 } 456 457 SkPerlinNoiseShader::PerlinNoiseShaderContext::~PerlinNoiseShaderContext() { delete fPaintingData; } 458 459 void SkPerlinNoiseShader::PerlinNoiseShaderContext::shadeSpan( 460 int x, int y, SkPMColor result[], int count) { 461 SkPoint point = SkPoint::Make(SkIntToScalar(x), SkIntToScalar(y)); 462 StitchData stitchData; 463 for (int i = 0; i < count; ++i) { 464 result[i] = shade(point, stitchData); 465 point.fX += SK_Scalar1; 466 } 467 } 468 469 ///////////////////////////////////////////////////////////////////// 470 471 #if SK_SUPPORT_GPU 472 473 class GrGLPerlinNoise : public GrGLSLFragmentProcessor { 474 public: 475 void emitCode(EmitArgs&) override; 476 477 static inline void GenKey(const GrProcessor&, const GrGLSLCaps&, GrProcessorKeyBuilder*); 478 479 protected: 480 void onSetData(const GrGLSLProgramDataManager&, const GrProcessor&) override; 481 482 private: 483 GrGLSLProgramDataManager::UniformHandle fStitchDataUni; 484 GrGLSLProgramDataManager::UniformHandle fBaseFrequencyUni; 485 486 typedef GrGLSLFragmentProcessor INHERITED; 487 }; 488 489 ///////////////////////////////////////////////////////////////////// 490 491 class GrPerlinNoiseEffect : public GrFragmentProcessor { 492 public: 493 static GrFragmentProcessor* Create(SkPerlinNoiseShader::Type type, 494 int numOctaves, bool stitchTiles, 495 SkPerlinNoiseShader::PaintingData* paintingData, 496 GrTexture* permutationsTexture, GrTexture* noiseTexture, 497 const SkMatrix& matrix) { 498 return new GrPerlinNoiseEffect(type, numOctaves, stitchTiles, paintingData, 499 permutationsTexture, noiseTexture, matrix); 500 } 501 502 virtual ~GrPerlinNoiseEffect() { delete fPaintingData; } 503 504 const char* name() const override { return "PerlinNoise"; } 505 506 const SkPerlinNoiseShader::StitchData& stitchData() const { return fPaintingData->fStitchDataInit; } 507 508 SkPerlinNoiseShader::Type type() const { return fType; } 509 bool stitchTiles() const { return fStitchTiles; } 510 const SkVector& baseFrequency() const { return fPaintingData->fBaseFrequency; } 511 int numOctaves() const { return fNumOctaves; } 512 const SkMatrix& matrix() const { return fCoordTransform.getMatrix(); } 513 514 private: 515 GrGLSLFragmentProcessor* onCreateGLSLInstance() const override { 516 return new GrGLPerlinNoise; 517 } 518 519 virtual void onGetGLSLProcessorKey(const GrGLSLCaps& caps, 520 GrProcessorKeyBuilder* b) const override { 521 GrGLPerlinNoise::GenKey(*this, caps, b); 522 } 523 524 bool onIsEqual(const GrFragmentProcessor& sBase) const override { 525 const GrPerlinNoiseEffect& s = sBase.cast<GrPerlinNoiseEffect>(); 526 return fType == s.fType && 527 fPaintingData->fBaseFrequency == s.fPaintingData->fBaseFrequency && 528 fNumOctaves == s.fNumOctaves && 529 fStitchTiles == s.fStitchTiles && 530 fPaintingData->fStitchDataInit == s.fPaintingData->fStitchDataInit; 531 } 532 533 void onComputeInvariantOutput(GrInvariantOutput* inout) const override { 534 inout->setToUnknown(GrInvariantOutput::kWillNot_ReadInput); 535 } 536 537 GrPerlinNoiseEffect(SkPerlinNoiseShader::Type type, 538 int numOctaves, bool stitchTiles, 539 SkPerlinNoiseShader::PaintingData* paintingData, 540 GrTexture* permutationsTexture, GrTexture* noiseTexture, 541 const SkMatrix& matrix) 542 : fType(type) 543 , fNumOctaves(numOctaves) 544 , fStitchTiles(stitchTiles) 545 , fPermutationsAccess(permutationsTexture) 546 , fNoiseAccess(noiseTexture) 547 , fPaintingData(paintingData) { 548 this->initClassID<GrPerlinNoiseEffect>(); 549 this->addTextureAccess(&fPermutationsAccess); 550 this->addTextureAccess(&fNoiseAccess); 551 fCoordTransform.reset(kLocal_GrCoordSet, matrix); 552 this->addCoordTransform(&fCoordTransform); 553 } 554 555 GR_DECLARE_FRAGMENT_PROCESSOR_TEST; 556 557 SkPerlinNoiseShader::Type fType; 558 GrCoordTransform fCoordTransform; 559 int fNumOctaves; 560 bool fStitchTiles; 561 GrTextureAccess fPermutationsAccess; 562 GrTextureAccess fNoiseAccess; 563 SkPerlinNoiseShader::PaintingData *fPaintingData; 564 565 private: 566 typedef GrFragmentProcessor INHERITED; 567 }; 568 569 ///////////////////////////////////////////////////////////////////// 570 GR_DEFINE_FRAGMENT_PROCESSOR_TEST(GrPerlinNoiseEffect); 571 572 const GrFragmentProcessor* GrPerlinNoiseEffect::TestCreate(GrProcessorTestData* d) { 573 int numOctaves = d->fRandom->nextRangeU(2, 10); 574 bool stitchTiles = d->fRandom->nextBool(); 575 SkScalar seed = SkIntToScalar(d->fRandom->nextU()); 576 SkISize tileSize = SkISize::Make(d->fRandom->nextRangeU(4, 4096), 577 d->fRandom->nextRangeU(4, 4096)); 578 SkScalar baseFrequencyX = d->fRandom->nextRangeScalar(0.01f, 579 0.99f); 580 SkScalar baseFrequencyY = d->fRandom->nextRangeScalar(0.01f, 581 0.99f); 582 583 SkAutoTUnref<SkShader> shader(d->fRandom->nextBool() ? 584 SkPerlinNoiseShader::CreateFractalNoise(baseFrequencyX, baseFrequencyY, numOctaves, seed, 585 stitchTiles ? &tileSize : nullptr) : 586 SkPerlinNoiseShader::CreateTurbulence(baseFrequencyX, baseFrequencyY, numOctaves, seed, 587 stitchTiles ? &tileSize : nullptr)); 588 589 return shader->asFragmentProcessor(d->fContext, 590 GrTest::TestMatrix(d->fRandom), nullptr, 591 kNone_SkFilterQuality); 592 } 593 594 void GrGLPerlinNoise::emitCode(EmitArgs& args) { 595 const GrPerlinNoiseEffect& pne = args.fFp.cast<GrPerlinNoiseEffect>(); 596 597 GrGLSLFPFragmentBuilder* fragBuilder = args.fFragBuilder; 598 GrGLSLUniformHandler* uniformHandler = args.fUniformHandler; 599 SkString vCoords = fragBuilder->ensureFSCoords2D(args.fCoords, 0); 600 601 fBaseFrequencyUni = uniformHandler->addUniform(kFragment_GrShaderFlag, 602 kVec2f_GrSLType, kDefault_GrSLPrecision, 603 "baseFrequency"); 604 const char* baseFrequencyUni = uniformHandler->getUniformCStr(fBaseFrequencyUni); 605 606 const char* stitchDataUni = nullptr; 607 if (pne.stitchTiles()) { 608 fStitchDataUni = uniformHandler->addUniform(kFragment_GrShaderFlag, 609 kVec2f_GrSLType, kDefault_GrSLPrecision, 610 "stitchData"); 611 stitchDataUni = uniformHandler->getUniformCStr(fStitchDataUni); 612 } 613 614 // There are 4 lines, so the center of each line is 1/8, 3/8, 5/8 and 7/8 615 const char* chanCoordR = "0.125"; 616 const char* chanCoordG = "0.375"; 617 const char* chanCoordB = "0.625"; 618 const char* chanCoordA = "0.875"; 619 const char* chanCoord = "chanCoord"; 620 const char* stitchData = "stitchData"; 621 const char* ratio = "ratio"; 622 const char* noiseVec = "noiseVec"; 623 const char* noiseSmooth = "noiseSmooth"; 624 const char* floorVal = "floorVal"; 625 const char* fractVal = "fractVal"; 626 const char* uv = "uv"; 627 const char* ab = "ab"; 628 const char* latticeIdx = "latticeIdx"; 629 const char* bcoords = "bcoords"; 630 const char* lattice = "lattice"; 631 const char* inc8bit = "0.00390625"; // 1.0 / 256.0 632 // This is the math to convert the two 16bit integer packed into rgba 8 bit input into a 633 // [-1,1] vector and perform a dot product between that vector and the provided vector. 634 const char* dotLattice = "dot(((%s.ga + %s.rb * vec2(%s)) * vec2(2.0) - vec2(1.0)), %s);"; 635 636 // Add noise function 637 static const GrGLSLShaderVar gPerlinNoiseArgs[] = { 638 GrGLSLShaderVar(chanCoord, kFloat_GrSLType), 639 GrGLSLShaderVar(noiseVec, kVec2f_GrSLType) 640 }; 641 642 static const GrGLSLShaderVar gPerlinNoiseStitchArgs[] = { 643 GrGLSLShaderVar(chanCoord, kFloat_GrSLType), 644 GrGLSLShaderVar(noiseVec, kVec2f_GrSLType), 645 GrGLSLShaderVar(stitchData, kVec2f_GrSLType) 646 }; 647 648 SkString noiseCode; 649 650 noiseCode.appendf("\tvec4 %s;\n", floorVal); 651 noiseCode.appendf("\t%s.xy = floor(%s);\n", floorVal, noiseVec); 652 noiseCode.appendf("\t%s.zw = %s.xy + vec2(1.0);\n", floorVal, floorVal); 653 noiseCode.appendf("\tvec2 %s = fract(%s);\n", fractVal, noiseVec); 654 655 // smooth curve : t * t * (3 - 2 * t) 656 noiseCode.appendf("\n\tvec2 %s = %s * %s * (vec2(3.0) - vec2(2.0) * %s);", 657 noiseSmooth, fractVal, fractVal, fractVal); 658 659 // Adjust frequencies if we're stitching tiles 660 if (pne.stitchTiles()) { 661 noiseCode.appendf("\n\tif(%s.x >= %s.x) { %s.x -= %s.x; }", 662 floorVal, stitchData, floorVal, stitchData); 663 noiseCode.appendf("\n\tif(%s.y >= %s.y) { %s.y -= %s.y; }", 664 floorVal, stitchData, floorVal, stitchData); 665 noiseCode.appendf("\n\tif(%s.z >= %s.x) { %s.z -= %s.x; }", 666 floorVal, stitchData, floorVal, stitchData); 667 noiseCode.appendf("\n\tif(%s.w >= %s.y) { %s.w -= %s.y; }", 668 floorVal, stitchData, floorVal, stitchData); 669 } 670 671 // Get texture coordinates and normalize 672 noiseCode.appendf("\n\t%s = fract(floor(mod(%s, 256.0)) / vec4(256.0));\n", 673 floorVal, floorVal); 674 675 // Get permutation for x 676 { 677 SkString xCoords(""); 678 xCoords.appendf("vec2(%s.x, 0.5)", floorVal); 679 680 noiseCode.appendf("\n\tvec2 %s;\n\t%s.x = ", latticeIdx, latticeIdx); 681 fragBuilder->appendTextureLookup(&noiseCode, args.fSamplers[0], xCoords.c_str(), 682 kVec2f_GrSLType); 683 noiseCode.append(".r;"); 684 } 685 686 // Get permutation for x + 1 687 { 688 SkString xCoords(""); 689 xCoords.appendf("vec2(%s.z, 0.5)", floorVal); 690 691 noiseCode.appendf("\n\t%s.y = ", latticeIdx); 692 fragBuilder->appendTextureLookup(&noiseCode, args.fSamplers[0], xCoords.c_str(), 693 kVec2f_GrSLType); 694 noiseCode.append(".r;"); 695 } 696 697 #if defined(SK_BUILD_FOR_ANDROID) 698 // Android rounding for Tegra devices, like, for example: Xoom (Tegra 2), Nexus 7 (Tegra 3). 699 // The issue is that colors aren't accurate enough on Tegra devices. For example, if an 8 bit 700 // value of 124 (or 0.486275 here) is entered, we can get a texture value of 123.513725 701 // (or 0.484368 here). The following rounding operation prevents these precision issues from 702 // affecting the result of the noise by making sure that we only have multiples of 1/255. 703 // (Note that 1/255 is about 0.003921569, which is the value used here). 704 noiseCode.appendf("\n\t%s = floor(%s * vec2(255.0) + vec2(0.5)) * vec2(0.003921569);", 705 latticeIdx, latticeIdx); 706 #endif 707 708 // Get (x,y) coordinates with the permutated x 709 noiseCode.appendf("\n\tvec4 %s = fract(%s.xyxy + %s.yyww);", bcoords, latticeIdx, floorVal); 710 711 noiseCode.appendf("\n\n\tvec2 %s;", uv); 712 // Compute u, at offset (0,0) 713 { 714 SkString latticeCoords(""); 715 latticeCoords.appendf("vec2(%s.x, %s)", bcoords, chanCoord); 716 noiseCode.appendf("\n\tvec4 %s = ", lattice); 717 fragBuilder->appendTextureLookup(&noiseCode, args.fSamplers[1], latticeCoords.c_str(), 718 kVec2f_GrSLType); 719 noiseCode.appendf(".bgra;\n\t%s.x = ", uv); 720 noiseCode.appendf(dotLattice, lattice, lattice, inc8bit, fractVal); 721 } 722 723 noiseCode.appendf("\n\t%s.x -= 1.0;", fractVal); 724 // Compute v, at offset (-1,0) 725 { 726 SkString latticeCoords(""); 727 latticeCoords.appendf("vec2(%s.y, %s)", bcoords, chanCoord); 728 noiseCode.append("\n\tlattice = "); 729 fragBuilder->appendTextureLookup(&noiseCode, args.fSamplers[1], latticeCoords.c_str(), 730 kVec2f_GrSLType); 731 noiseCode.appendf(".bgra;\n\t%s.y = ", uv); 732 noiseCode.appendf(dotLattice, lattice, lattice, inc8bit, fractVal); 733 } 734 735 // Compute 'a' as a linear interpolation of 'u' and 'v' 736 noiseCode.appendf("\n\tvec2 %s;", ab); 737 noiseCode.appendf("\n\t%s.x = mix(%s.x, %s.y, %s.x);", ab, uv, uv, noiseSmooth); 738 739 noiseCode.appendf("\n\t%s.y -= 1.0;", fractVal); 740 // Compute v, at offset (-1,-1) 741 { 742 SkString latticeCoords(""); 743 latticeCoords.appendf("vec2(%s.w, %s)", bcoords, chanCoord); 744 noiseCode.append("\n\tlattice = "); 745 fragBuilder->appendTextureLookup(&noiseCode, args.fSamplers[1], latticeCoords.c_str(), 746 kVec2f_GrSLType); 747 noiseCode.appendf(".bgra;\n\t%s.y = ", uv); 748 noiseCode.appendf(dotLattice, lattice, lattice, inc8bit, fractVal); 749 } 750 751 noiseCode.appendf("\n\t%s.x += 1.0;", fractVal); 752 // Compute u, at offset (0,-1) 753 { 754 SkString latticeCoords(""); 755 latticeCoords.appendf("vec2(%s.z, %s)", bcoords, chanCoord); 756 noiseCode.append("\n\tlattice = "); 757 fragBuilder->appendTextureLookup(&noiseCode, args.fSamplers[1], latticeCoords.c_str(), 758 kVec2f_GrSLType); 759 noiseCode.appendf(".bgra;\n\t%s.x = ", uv); 760 noiseCode.appendf(dotLattice, lattice, lattice, inc8bit, fractVal); 761 } 762 763 // Compute 'b' as a linear interpolation of 'u' and 'v' 764 noiseCode.appendf("\n\t%s.y = mix(%s.x, %s.y, %s.x);", ab, uv, uv, noiseSmooth); 765 // Compute the noise as a linear interpolation of 'a' and 'b' 766 noiseCode.appendf("\n\treturn mix(%s.x, %s.y, %s.y);\n", ab, ab, noiseSmooth); 767 768 SkString noiseFuncName; 769 if (pne.stitchTiles()) { 770 fragBuilder->emitFunction(kFloat_GrSLType, 771 "perlinnoise", SK_ARRAY_COUNT(gPerlinNoiseStitchArgs), 772 gPerlinNoiseStitchArgs, noiseCode.c_str(), &noiseFuncName); 773 } else { 774 fragBuilder->emitFunction(kFloat_GrSLType, 775 "perlinnoise", SK_ARRAY_COUNT(gPerlinNoiseArgs), 776 gPerlinNoiseArgs, noiseCode.c_str(), &noiseFuncName); 777 } 778 779 // There are rounding errors if the floor operation is not performed here 780 fragBuilder->codeAppendf("\n\t\tvec2 %s = floor(%s.xy) * %s;", 781 noiseVec, vCoords.c_str(), baseFrequencyUni); 782 783 // Clear the color accumulator 784 fragBuilder->codeAppendf("\n\t\t%s = vec4(0.0);", args.fOutputColor); 785 786 if (pne.stitchTiles()) { 787 // Set up TurbulenceInitial stitch values. 788 fragBuilder->codeAppendf("vec2 %s = %s;", stitchData, stitchDataUni); 789 } 790 791 fragBuilder->codeAppendf("float %s = 1.0;", ratio); 792 793 // Loop over all octaves 794 fragBuilder->codeAppendf("for (int octave = 0; octave < %d; ++octave) {", pne.numOctaves()); 795 796 fragBuilder->codeAppendf("%s += ", args.fOutputColor); 797 if (pne.type() != SkPerlinNoiseShader::kFractalNoise_Type) { 798 fragBuilder->codeAppend("abs("); 799 } 800 if (pne.stitchTiles()) { 801 fragBuilder->codeAppendf( 802 "vec4(\n\t\t\t\t%s(%s, %s, %s),\n\t\t\t\t%s(%s, %s, %s)," 803 "\n\t\t\t\t%s(%s, %s, %s),\n\t\t\t\t%s(%s, %s, %s))", 804 noiseFuncName.c_str(), chanCoordR, noiseVec, stitchData, 805 noiseFuncName.c_str(), chanCoordG, noiseVec, stitchData, 806 noiseFuncName.c_str(), chanCoordB, noiseVec, stitchData, 807 noiseFuncName.c_str(), chanCoordA, noiseVec, stitchData); 808 } else { 809 fragBuilder->codeAppendf( 810 "vec4(\n\t\t\t\t%s(%s, %s),\n\t\t\t\t%s(%s, %s)," 811 "\n\t\t\t\t%s(%s, %s),\n\t\t\t\t%s(%s, %s))", 812 noiseFuncName.c_str(), chanCoordR, noiseVec, 813 noiseFuncName.c_str(), chanCoordG, noiseVec, 814 noiseFuncName.c_str(), chanCoordB, noiseVec, 815 noiseFuncName.c_str(), chanCoordA, noiseVec); 816 } 817 if (pne.type() != SkPerlinNoiseShader::kFractalNoise_Type) { 818 fragBuilder->codeAppendf(")"); // end of "abs(" 819 } 820 fragBuilder->codeAppendf(" * %s;", ratio); 821 822 fragBuilder->codeAppendf("\n\t\t\t%s *= vec2(2.0);", noiseVec); 823 fragBuilder->codeAppendf("\n\t\t\t%s *= 0.5;", ratio); 824 825 if (pne.stitchTiles()) { 826 fragBuilder->codeAppendf("\n\t\t\t%s *= vec2(2.0);", stitchData); 827 } 828 fragBuilder->codeAppend("\n\t\t}"); // end of the for loop on octaves 829 830 if (pne.type() == SkPerlinNoiseShader::kFractalNoise_Type) { 831 // The value of turbulenceFunctionResult comes from ((turbulenceFunctionResult) + 1) / 2 832 // by fractalNoise and (turbulenceFunctionResult) by turbulence. 833 fragBuilder->codeAppendf("\n\t\t%s = %s * vec4(0.5) + vec4(0.5);", 834 args.fOutputColor,args.fOutputColor); 835 } 836 837 // Clamp values 838 fragBuilder->codeAppendf("\n\t\t%s = clamp(%s, 0.0, 1.0);", args.fOutputColor, args.fOutputColor); 839 840 // Pre-multiply the result 841 fragBuilder->codeAppendf("\n\t\t%s = vec4(%s.rgb * %s.aaa, %s.a);\n", 842 args.fOutputColor, args.fOutputColor, 843 args.fOutputColor, args.fOutputColor); 844 } 845 846 void GrGLPerlinNoise::GenKey(const GrProcessor& processor, const GrGLSLCaps&, 847 GrProcessorKeyBuilder* b) { 848 const GrPerlinNoiseEffect& turbulence = processor.cast<GrPerlinNoiseEffect>(); 849 850 uint32_t key = turbulence.numOctaves(); 851 852 key = key << 3; // Make room for next 3 bits 853 854 switch (turbulence.type()) { 855 case SkPerlinNoiseShader::kFractalNoise_Type: 856 key |= 0x1; 857 break; 858 case SkPerlinNoiseShader::kTurbulence_Type: 859 key |= 0x2; 860 break; 861 default: 862 // leave key at 0 863 break; 864 } 865 866 if (turbulence.stitchTiles()) { 867 key |= 0x4; // Flip the 3rd bit if tile stitching is on 868 } 869 870 b->add32(key); 871 } 872 873 void GrGLPerlinNoise::onSetData(const GrGLSLProgramDataManager& pdman, 874 const GrProcessor& processor) { 875 INHERITED::onSetData(pdman, processor); 876 877 const GrPerlinNoiseEffect& turbulence = processor.cast<GrPerlinNoiseEffect>(); 878 879 const SkVector& baseFrequency = turbulence.baseFrequency(); 880 pdman.set2f(fBaseFrequencyUni, baseFrequency.fX, baseFrequency.fY); 881 882 if (turbulence.stitchTiles()) { 883 const SkPerlinNoiseShader::StitchData& stitchData = turbulence.stitchData(); 884 pdman.set2f(fStitchDataUni, SkIntToScalar(stitchData.fWidth), 885 SkIntToScalar(stitchData.fHeight)); 886 } 887 } 888 889 ///////////////////////////////////////////////////////////////////// 890 const GrFragmentProcessor* SkPerlinNoiseShader::asFragmentProcessor( 891 GrContext* context, 892 const SkMatrix& viewM, 893 const SkMatrix* externalLocalMatrix, 894 SkFilterQuality) const { 895 SkASSERT(context); 896 897 SkMatrix localMatrix = this->getLocalMatrix(); 898 if (externalLocalMatrix) { 899 localMatrix.preConcat(*externalLocalMatrix); 900 } 901 902 SkMatrix matrix = viewM; 903 matrix.preConcat(localMatrix); 904 905 if (0 == fNumOctaves) { 906 if (kFractalNoise_Type == fType) { 907 // Extract the incoming alpha and emit rgba = (a/4, a/4, a/4, a/2) 908 SkAutoTUnref<const GrFragmentProcessor> inner( 909 GrConstColorProcessor::Create(0x80404040, 910 GrConstColorProcessor::kModulateRGBA_InputMode)); 911 return GrFragmentProcessor::MulOutputByInputAlpha(inner); 912 } 913 // Emit zero. 914 return GrConstColorProcessor::Create(0x0, GrConstColorProcessor::kIgnore_InputMode); 915 } 916 917 // Either we don't stitch tiles, either we have a valid tile size 918 SkASSERT(!fStitchTiles || !fTileSize.isEmpty()); 919 920 SkPerlinNoiseShader::PaintingData* paintingData = 921 new PaintingData(fTileSize, fSeed, fBaseFrequencyX, fBaseFrequencyY, matrix); 922 SkAutoTUnref<GrTexture> permutationsTexture( 923 GrRefCachedBitmapTexture(context, paintingData->getPermutationsBitmap(), 924 GrTextureParams::ClampNoFilter())); 925 SkAutoTUnref<GrTexture> noiseTexture( 926 GrRefCachedBitmapTexture(context, paintingData->getNoiseBitmap(), 927 GrTextureParams::ClampNoFilter())); 928 929 SkMatrix m = viewM; 930 m.setTranslateX(-localMatrix.getTranslateX() + SK_Scalar1); 931 m.setTranslateY(-localMatrix.getTranslateY() + SK_Scalar1); 932 if ((permutationsTexture) && (noiseTexture)) { 933 SkAutoTUnref<GrFragmentProcessor> inner( 934 GrPerlinNoiseEffect::Create(fType, 935 fNumOctaves, 936 fStitchTiles, 937 paintingData, 938 permutationsTexture, noiseTexture, 939 m)); 940 return GrFragmentProcessor::MulOutputByInputAlpha(inner); 941 } 942 delete paintingData; 943 return nullptr; 944 } 945 946 #endif 947 948 #ifndef SK_IGNORE_TO_STRING 949 void SkPerlinNoiseShader::toString(SkString* str) const { 950 str->append("SkPerlinNoiseShader: ("); 951 952 str->append("type: "); 953 switch (fType) { 954 case kFractalNoise_Type: 955 str->append("\"fractal noise\""); 956 break; 957 case kTurbulence_Type: 958 str->append("\"turbulence\""); 959 break; 960 default: 961 str->append("\"unknown\""); 962 break; 963 } 964 str->append(" base frequency: ("); 965 str->appendScalar(fBaseFrequencyX); 966 str->append(", "); 967 str->appendScalar(fBaseFrequencyY); 968 str->append(") number of octaves: "); 969 str->appendS32(fNumOctaves); 970 str->append(" seed: "); 971 str->appendScalar(fSeed); 972 str->append(" stitch tiles: "); 973 str->append(fStitchTiles ? "true " : "false "); 974 975 this->INHERITED::toString(str); 976 977 str->append(")"); 978 } 979 #endif 980
