2 * Copyright 2013 Google Inc.
4 * Use of this source code is governed by a BSD-style license that can be
5 * found in the LICENSE file.
9 #include "SkPerlinNoiseShader.h"
10 #include "SkColorFilter.h"
11 #include "SkReadBuffer.h"
12 #include "SkWriteBuffer.h"
14 #include "SkUnPreMultiply.h"
18 #include "GrContext.h"
19 #include "GrCoordTransform.h"
20 #include "GrInvariantOutput.h"
22 #include "effects/GrConstColorProcessor.h"
23 #include "glsl/GrGLSLFragmentProcessor.h"
24 #include "glsl/GrGLSLFragmentShaderBuilder.h"
25 #include "glsl/GrGLSLProgramBuilder.h"
26 #include "glsl/GrGLSLProgramDataManager.h"
29 static const int kBlockSize = 256;
30 static const int kBlockMask = kBlockSize - 1;
31 static const int kPerlinNoise = 4096;
32 static const int kRandMaximum = SK_MaxS32; // 2**31 - 1
36 // noiseValue is the color component's value (or color)
37 // limitValue is the maximum perlin noise array index value allowed
38 // newValue is the current noise dimension (either width or height)
39 inline int checkNoise(int noiseValue, int limitValue, int newValue) {
40 // If the noise value would bring us out of bounds of the current noise array while we are
41 // stiching noise tiles together, wrap the noise around the current dimension of the noise to
42 // stay within the array bounds in a continuous fashion (so that tiling lines are not visible)
43 if (noiseValue >= limitValue) {
44 noiseValue -= newValue;
49 inline SkScalar smoothCurve(SkScalar t) {
50 static const SkScalar SK_Scalar3 = 3.0f;
52 // returns t * t * (3 - 2 * t)
53 return SkScalarMul(SkScalarSquare(t), SK_Scalar3 - 2 * t);
58 struct SkPerlinNoiseShader::StitchData {
66 bool operator==(const StitchData& other) const {
67 return fWidth == other.fWidth &&
68 fWrapX == other.fWrapX &&
69 fHeight == other.fHeight &&
70 fWrapY == other.fWrapY;
73 int fWidth; // How much to subtract to wrap for stitching.
74 int fWrapX; // Minimum value to wrap.
79 struct SkPerlinNoiseShader::PaintingData {
80 PaintingData(const SkISize& tileSize, SkScalar seed,
81 SkScalar baseFrequencyX, SkScalar baseFrequencyY,
82 const SkMatrix& matrix)
85 { SkScalarInvert(baseFrequencyX), SkScalarInvert(baseFrequencyY) },
86 { SkIntToScalar(tileSize.fWidth), SkIntToScalar(tileSize.fHeight) },
88 matrix.mapVectors(vec, 2);
90 fBaseFrequency.set(SkScalarInvert(vec[0].fX), SkScalarInvert(vec[0].fY));
91 fTileSize.set(SkScalarRoundToInt(vec[1].fX), SkScalarRoundToInt(vec[1].fY));
93 if (!fTileSize.isEmpty()) {
98 fPermutationsBitmap.setInfo(SkImageInfo::MakeA8(kBlockSize, 1));
99 fPermutationsBitmap.setPixels(fLatticeSelector);
101 fNoiseBitmap.setInfo(SkImageInfo::MakeN32Premul(kBlockSize, 4));
102 fNoiseBitmap.setPixels(fNoise[0][0]);
107 uint8_t fLatticeSelector[kBlockSize];
108 uint16_t fNoise[4][kBlockSize][2];
109 SkPoint fGradient[4][kBlockSize];
111 SkVector fBaseFrequency;
112 StitchData fStitchDataInit;
117 SkBitmap fPermutationsBitmap;
118 SkBitmap fNoiseBitmap;
121 inline int random() {
122 static const int gRandAmplitude = 16807; // 7**5; primitive root of m
123 static const int gRandQ = 127773; // m / a
124 static const int gRandR = 2836; // m % a
126 int result = gRandAmplitude * (fSeed % gRandQ) - gRandR * (fSeed / gRandQ);
128 result += kRandMaximum;
133 // Only called once. Could be part of the constructor.
134 void init(SkScalar seed)
136 static const SkScalar gInvBlockSizef = SkScalarInvert(SkIntToScalar(kBlockSize));
138 // According to the SVG spec, we must truncate (not round) the seed value.
139 fSeed = SkScalarTruncToInt(seed);
140 // The seed value clamp to the range [1, kRandMaximum - 1].
142 fSeed = -(fSeed % (kRandMaximum - 1)) + 1;
144 if (fSeed > kRandMaximum - 1) {
145 fSeed = kRandMaximum - 1;
147 for (int channel = 0; channel < 4; ++channel) {
148 for (int i = 0; i < kBlockSize; ++i) {
149 fLatticeSelector[i] = i;
150 fNoise[channel][i][0] = (random() % (2 * kBlockSize));
151 fNoise[channel][i][1] = (random() % (2 * kBlockSize));
154 for (int i = kBlockSize - 1; i > 0; --i) {
155 int k = fLatticeSelector[i];
156 int j = random() % kBlockSize;
158 SkASSERT(j < kBlockSize);
159 fLatticeSelector[i] = fLatticeSelector[j];
160 fLatticeSelector[j] = k;
163 // Perform the permutations now
166 uint16_t noise[4][kBlockSize][2];
167 for (int i = 0; i < kBlockSize; ++i) {
168 for (int channel = 0; channel < 4; ++channel) {
169 for (int j = 0; j < 2; ++j) {
170 noise[channel][i][j] = fNoise[channel][i][j];
174 // Do permutations on noise data
175 for (int i = 0; i < kBlockSize; ++i) {
176 for (int channel = 0; channel < 4; ++channel) {
177 for (int j = 0; j < 2; ++j) {
178 fNoise[channel][i][j] = noise[channel][fLatticeSelector[i]][j];
184 // Half of the largest possible value for 16 bit unsigned int
185 static const SkScalar gHalfMax16bits = 32767.5f;
187 // Compute gradients from permutated noise data
188 for (int channel = 0; channel < 4; ++channel) {
189 for (int i = 0; i < kBlockSize; ++i) {
190 fGradient[channel][i] = SkPoint::Make(
191 SkScalarMul(SkIntToScalar(fNoise[channel][i][0] - kBlockSize),
193 SkScalarMul(SkIntToScalar(fNoise[channel][i][1] - kBlockSize),
195 fGradient[channel][i].normalize();
196 // Put the normalized gradient back into the noise data
197 fNoise[channel][i][0] = SkScalarRoundToInt(SkScalarMul(
198 fGradient[channel][i].fX + SK_Scalar1, gHalfMax16bits));
199 fNoise[channel][i][1] = SkScalarRoundToInt(SkScalarMul(
200 fGradient[channel][i].fY + SK_Scalar1, gHalfMax16bits));
205 // Only called once. Could be part of the constructor.
207 SkScalar tileWidth = SkIntToScalar(fTileSize.width());
208 SkScalar tileHeight = SkIntToScalar(fTileSize.height());
209 SkASSERT(tileWidth > 0 && tileHeight > 0);
210 // When stitching tiled turbulence, the frequencies must be adjusted
211 // so that the tile borders will be continuous.
212 if (fBaseFrequency.fX) {
213 SkScalar lowFrequencx =
214 SkScalarFloorToScalar(tileWidth * fBaseFrequency.fX) / tileWidth;
215 SkScalar highFrequencx =
216 SkScalarCeilToScalar(tileWidth * fBaseFrequency.fX) / tileWidth;
217 // BaseFrequency should be non-negative according to the standard.
218 if (fBaseFrequency.fX / lowFrequencx < highFrequencx / fBaseFrequency.fX) {
219 fBaseFrequency.fX = lowFrequencx;
221 fBaseFrequency.fX = highFrequencx;
224 if (fBaseFrequency.fY) {
225 SkScalar lowFrequency =
226 SkScalarFloorToScalar(tileHeight * fBaseFrequency.fY) / tileHeight;
227 SkScalar highFrequency =
228 SkScalarCeilToScalar(tileHeight * fBaseFrequency.fY) / tileHeight;
229 if (fBaseFrequency.fY / lowFrequency < highFrequency / fBaseFrequency.fY) {
230 fBaseFrequency.fY = lowFrequency;
232 fBaseFrequency.fY = highFrequency;
235 // Set up TurbulenceInitial stitch values.
236 fStitchDataInit.fWidth =
237 SkScalarRoundToInt(tileWidth * fBaseFrequency.fX);
238 fStitchDataInit.fWrapX = kPerlinNoise + fStitchDataInit.fWidth;
239 fStitchDataInit.fHeight =
240 SkScalarRoundToInt(tileHeight * fBaseFrequency.fY);
241 fStitchDataInit.fWrapY = kPerlinNoise + fStitchDataInit.fHeight;
247 const SkBitmap& getPermutationsBitmap() const { return fPermutationsBitmap; }
249 const SkBitmap& getNoiseBitmap() const { return fNoiseBitmap; }
253 SkShader* SkPerlinNoiseShader::CreateFractalNoise(SkScalar baseFrequencyX, SkScalar baseFrequencyY,
254 int numOctaves, SkScalar seed,
255 const SkISize* tileSize) {
256 return new SkPerlinNoiseShader(kFractalNoise_Type, baseFrequencyX, baseFrequencyY, numOctaves,
260 SkShader* SkPerlinNoiseShader::CreateTurbulence(SkScalar baseFrequencyX, SkScalar baseFrequencyY,
261 int numOctaves, SkScalar seed,
262 const SkISize* tileSize) {
263 return new SkPerlinNoiseShader(kTurbulence_Type, baseFrequencyX, baseFrequencyY, numOctaves,
267 SkPerlinNoiseShader::SkPerlinNoiseShader(SkPerlinNoiseShader::Type type,
268 SkScalar baseFrequencyX,
269 SkScalar baseFrequencyY,
272 const SkISize* tileSize)
274 , fBaseFrequencyX(baseFrequencyX)
275 , fBaseFrequencyY(baseFrequencyY)
276 , fNumOctaves(numOctaves > 255 ? 255 : numOctaves/*[0,255] octaves allowed*/)
278 , fTileSize(nullptr == tileSize ? SkISize::Make(0, 0) : *tileSize)
279 , fStitchTiles(!fTileSize.isEmpty())
281 SkASSERT(numOctaves >= 0 && numOctaves < 256);
284 SkPerlinNoiseShader::~SkPerlinNoiseShader() {
287 SkFlattenable* SkPerlinNoiseShader::CreateProc(SkReadBuffer& buffer) {
288 Type type = (Type)buffer.readInt();
289 SkScalar freqX = buffer.readScalar();
290 SkScalar freqY = buffer.readScalar();
291 int octaves = buffer.readInt();
292 SkScalar seed = buffer.readScalar();
294 tileSize.fWidth = buffer.readInt();
295 tileSize.fHeight = buffer.readInt();
298 case kFractalNoise_Type:
299 return SkPerlinNoiseShader::CreateFractalNoise(freqX, freqY, octaves, seed, &tileSize);
300 case kTurbulence_Type:
301 return SkPerlinNoiseShader::CreateTubulence(freqX, freqY, octaves, seed, &tileSize);
307 void SkPerlinNoiseShader::flatten(SkWriteBuffer& buffer) const {
308 buffer.writeInt((int) fType);
309 buffer.writeScalar(fBaseFrequencyX);
310 buffer.writeScalar(fBaseFrequencyY);
311 buffer.writeInt(fNumOctaves);
312 buffer.writeScalar(fSeed);
313 buffer.writeInt(fTileSize.fWidth);
314 buffer.writeInt(fTileSize.fHeight);
317 SkScalar SkPerlinNoiseShader::PerlinNoiseShaderContext::noise2D(
318 int channel, const StitchData& stitchData, const SkPoint& noiseVector) const {
320 int noisePositionIntegerValue;
321 int nextNoisePositionIntegerValue;
322 SkScalar noisePositionFractionValue;
323 Noise(SkScalar component)
325 SkScalar position = component + kPerlinNoise;
326 noisePositionIntegerValue = SkScalarFloorToInt(position);
327 noisePositionFractionValue = position - SkIntToScalar(noisePositionIntegerValue);
328 nextNoisePositionIntegerValue = noisePositionIntegerValue + 1;
331 Noise noiseX(noiseVector.x());
332 Noise noiseY(noiseVector.y());
334 const SkPerlinNoiseShader& perlinNoiseShader = static_cast<const SkPerlinNoiseShader&>(fShader);
335 // If stitching, adjust lattice points accordingly.
336 if (perlinNoiseShader.fStitchTiles) {
337 noiseX.noisePositionIntegerValue =
338 checkNoise(noiseX.noisePositionIntegerValue, stitchData.fWrapX, stitchData.fWidth);
339 noiseY.noisePositionIntegerValue =
340 checkNoise(noiseY.noisePositionIntegerValue, stitchData.fWrapY, stitchData.fHeight);
341 noiseX.nextNoisePositionIntegerValue =
342 checkNoise(noiseX.nextNoisePositionIntegerValue, stitchData.fWrapX, stitchData.fWidth);
343 noiseY.nextNoisePositionIntegerValue =
344 checkNoise(noiseY.nextNoisePositionIntegerValue, stitchData.fWrapY, stitchData.fHeight);
346 noiseX.noisePositionIntegerValue &= kBlockMask;
347 noiseY.noisePositionIntegerValue &= kBlockMask;
348 noiseX.nextNoisePositionIntegerValue &= kBlockMask;
349 noiseY.nextNoisePositionIntegerValue &= kBlockMask;
351 fPaintingData->fLatticeSelector[noiseX.noisePositionIntegerValue];
353 fPaintingData->fLatticeSelector[noiseX.nextNoisePositionIntegerValue];
354 int b00 = (i + noiseY.noisePositionIntegerValue) & kBlockMask;
355 int b10 = (j + noiseY.noisePositionIntegerValue) & kBlockMask;
356 int b01 = (i + noiseY.nextNoisePositionIntegerValue) & kBlockMask;
357 int b11 = (j + noiseY.nextNoisePositionIntegerValue) & kBlockMask;
358 SkScalar sx = smoothCurve(noiseX.noisePositionFractionValue);
359 SkScalar sy = smoothCurve(noiseY.noisePositionFractionValue);
360 // This is taken 1:1 from SVG spec: http://www.w3.org/TR/SVG11/filters.html#feTurbulenceElement
361 SkPoint fractionValue = SkPoint::Make(noiseX.noisePositionFractionValue,
362 noiseY.noisePositionFractionValue); // Offset (0,0)
363 u = fPaintingData->fGradient[channel][b00].dot(fractionValue);
364 fractionValue.fX -= SK_Scalar1; // Offset (-1,0)
365 v = fPaintingData->fGradient[channel][b10].dot(fractionValue);
366 SkScalar a = SkScalarInterp(u, v, sx);
367 fractionValue.fY -= SK_Scalar1; // Offset (-1,-1)
368 v = fPaintingData->fGradient[channel][b11].dot(fractionValue);
369 fractionValue.fX = noiseX.noisePositionFractionValue; // Offset (0,-1)
370 u = fPaintingData->fGradient[channel][b01].dot(fractionValue);
371 SkScalar b = SkScalarInterp(u, v, sx);
372 return SkScalarInterp(a, b, sy);
375 SkScalar SkPerlinNoiseShader::PerlinNoiseShaderContext::calculateTurbulenceValueForPoint(
376 int channel, StitchData& stitchData, const SkPoint& point) const {
377 const SkPerlinNoiseShader& perlinNoiseShader = static_cast<const SkPerlinNoiseShader&>(fShader);
378 if (perlinNoiseShader.fStitchTiles) {
379 // Set up TurbulenceInitial stitch values.
380 stitchData = fPaintingData->fStitchDataInit;
382 SkScalar turbulenceFunctionResult = 0;
383 SkPoint noiseVector(SkPoint::Make(SkScalarMul(point.x(), fPaintingData->fBaseFrequency.fX),
384 SkScalarMul(point.y(), fPaintingData->fBaseFrequency.fY)));
385 SkScalar ratio = SK_Scalar1;
386 for (int octave = 0; octave < perlinNoiseShader.fNumOctaves; ++octave) {
387 SkScalar noise = noise2D(channel, stitchData, noiseVector);
388 SkScalar numer = (perlinNoiseShader.fType == kFractalNoise_Type) ?
389 noise : SkScalarAbs(noise);
390 turbulenceFunctionResult += numer / ratio;
394 if (perlinNoiseShader.fStitchTiles) {
395 // Update stitch values
396 stitchData.fWidth *= 2;
397 stitchData.fWrapX = stitchData.fWidth + kPerlinNoise;
398 stitchData.fHeight *= 2;
399 stitchData.fWrapY = stitchData.fHeight + kPerlinNoise;
403 // The value of turbulenceFunctionResult comes from ((turbulenceFunctionResult) + 1) / 2
404 // by fractalNoise and (turbulenceFunctionResult) by turbulence.
405 if (perlinNoiseShader.fType == kFractalNoise_Type) {
406 turbulenceFunctionResult =
407 SkScalarMul(turbulenceFunctionResult, SK_ScalarHalf) + SK_ScalarHalf;
410 if (channel == 3) { // Scale alpha by paint value
411 turbulenceFunctionResult *= SkIntToScalar(getPaintAlpha()) / 255;
415 return SkScalarPin(turbulenceFunctionResult, 0, SK_Scalar1);
418 SkPMColor SkPerlinNoiseShader::PerlinNoiseShaderContext::shade(
419 const SkPoint& point, StitchData& stitchData) const {
421 fMatrix.mapPoints(&newPoint, &point, 1);
422 newPoint.fX = SkScalarRoundToScalar(newPoint.fX);
423 newPoint.fY = SkScalarRoundToScalar(newPoint.fY);
426 for (int channel = 3; channel >= 0; --channel) {
427 rgba[channel] = SkScalarFloorToInt(255 *
428 calculateTurbulenceValueForPoint(channel, stitchData, newPoint));
430 return SkPreMultiplyARGB(rgba[3], rgba[0], rgba[1], rgba[2]);
433 SkShader::Context* SkPerlinNoiseShader::onCreateContext(const ContextRec& rec,
434 void* storage) const {
435 return new (storage) PerlinNoiseShaderContext(*this, rec);
438 size_t SkPerlinNoiseShader::contextSize() const {
439 return sizeof(PerlinNoiseShaderContext);
442 SkPerlinNoiseShader::PerlinNoiseShaderContext::PerlinNoiseShaderContext(
443 const SkPerlinNoiseShader& shader, const ContextRec& rec)
444 : INHERITED(shader, rec)
446 SkMatrix newMatrix = *rec.fMatrix;
447 newMatrix.preConcat(shader.getLocalMatrix());
448 if (rec.fLocalMatrix) {
449 newMatrix.preConcat(*rec.fLocalMatrix);
451 // This (1,1) translation is due to WebKit's 1 based coordinates for the noise
452 // (as opposed to 0 based, usually). The same adjustment is in the setData() function.
453 fMatrix.setTranslate(-newMatrix.getTranslateX() + SK_Scalar1, -newMatrix.getTranslateY() + SK_Scalar1);
454 fPaintingData = new PaintingData(shader.fTileSize, shader.fSeed, shader.fBaseFrequencyX,
455 shader.fBaseFrequencyY, newMatrix);
458 SkPerlinNoiseShader::PerlinNoiseShaderContext::~PerlinNoiseShaderContext() { delete fPaintingData; }
460 void SkPerlinNoiseShader::PerlinNoiseShaderContext::shadeSpan(
461 int x, int y, SkPMColor result[], int count) {
462 SkPoint point = SkPoint::Make(SkIntToScalar(x), SkIntToScalar(y));
463 StitchData stitchData;
464 for (int i = 0; i < count; ++i) {
465 result[i] = shade(point, stitchData);
466 point.fX += SK_Scalar1;
470 void SkPerlinNoiseShader::PerlinNoiseShaderContext::shadeSpan16(
471 int x, int y, uint16_t result[], int count) {
472 SkPoint point = SkPoint::Make(SkIntToScalar(x), SkIntToScalar(y));
473 StitchData stitchData;
475 for (int i = 0; i < count; ++i) {
476 unsigned dither = DITHER_VALUE(x);
477 result[i] = SkDitherRGB32To565(shade(point, stitchData), dither);
479 point.fX += SK_Scalar1;
483 /////////////////////////////////////////////////////////////////////
487 class GrGLPerlinNoise : public GrGLSLFragmentProcessor {
489 GrGLPerlinNoise(const GrProcessor&);
490 virtual ~GrGLPerlinNoise() {}
492 virtual void emitCode(EmitArgs&) override;
494 static inline void GenKey(const GrProcessor&, const GrGLSLCaps&, GrProcessorKeyBuilder* b);
497 void onSetData(const GrGLSLProgramDataManager&, const GrProcessor&) override;
501 GrGLSLProgramDataManager::UniformHandle fStitchDataUni;
502 SkPerlinNoiseShader::Type fType;
505 GrGLSLProgramDataManager::UniformHandle fBaseFrequencyUni;
508 typedef GrGLSLFragmentProcessor INHERITED;
511 /////////////////////////////////////////////////////////////////////
513 class GrPerlinNoiseEffect : public GrFragmentProcessor {
515 static GrFragmentProcessor* Create(SkPerlinNoiseShader::Type type,
516 int numOctaves, bool stitchTiles,
517 SkPerlinNoiseShader::PaintingData* paintingData,
518 GrTexture* permutationsTexture, GrTexture* noiseTexture,
519 const SkMatrix& matrix) {
520 return new GrPerlinNoiseEffect(type, numOctaves, stitchTiles, paintingData,
521 permutationsTexture, noiseTexture, matrix);
524 virtual ~GrPerlinNoiseEffect() { delete fPaintingData; }
526 const char* name() const override { return "PerlinNoise"; }
528 const SkPerlinNoiseShader::StitchData& stitchData() const { return fPaintingData->fStitchDataInit; }
530 SkPerlinNoiseShader::Type type() const { return fType; }
531 bool stitchTiles() const { return fStitchTiles; }
532 const SkVector& baseFrequency() const { return fPaintingData->fBaseFrequency; }
533 int numOctaves() const { return fNumOctaves; }
534 const SkMatrix& matrix() const { return fCoordTransform.getMatrix(); }
537 GrGLSLFragmentProcessor* onCreateGLInstance() const override {
538 return new GrGLPerlinNoise(*this);
541 virtual void onGetGLProcessorKey(const GrGLSLCaps& caps,
542 GrProcessorKeyBuilder* b) const override {
543 GrGLPerlinNoise::GenKey(*this, caps, b);
546 bool onIsEqual(const GrFragmentProcessor& sBase) const override {
547 const GrPerlinNoiseEffect& s = sBase.cast<GrPerlinNoiseEffect>();
548 return fType == s.fType &&
549 fPaintingData->fBaseFrequency == s.fPaintingData->fBaseFrequency &&
550 fNumOctaves == s.fNumOctaves &&
551 fStitchTiles == s.fStitchTiles &&
552 fPaintingData->fStitchDataInit == s.fPaintingData->fStitchDataInit;
555 void onComputeInvariantOutput(GrInvariantOutput* inout) const override {
556 inout->setToUnknown(GrInvariantOutput::kWillNot_ReadInput);
559 GrPerlinNoiseEffect(SkPerlinNoiseShader::Type type,
560 int numOctaves, bool stitchTiles,
561 SkPerlinNoiseShader::PaintingData* paintingData,
562 GrTexture* permutationsTexture, GrTexture* noiseTexture,
563 const SkMatrix& matrix)
565 , fNumOctaves(numOctaves)
566 , fStitchTiles(stitchTiles)
567 , fPermutationsAccess(permutationsTexture)
568 , fNoiseAccess(noiseTexture)
569 , fPaintingData(paintingData) {
570 this->initClassID<GrPerlinNoiseEffect>();
571 this->addTextureAccess(&fPermutationsAccess);
572 this->addTextureAccess(&fNoiseAccess);
573 fCoordTransform.reset(kLocal_GrCoordSet, matrix);
574 this->addCoordTransform(&fCoordTransform);
577 GR_DECLARE_FRAGMENT_PROCESSOR_TEST;
579 SkPerlinNoiseShader::Type fType;
580 GrCoordTransform fCoordTransform;
583 GrTextureAccess fPermutationsAccess;
584 GrTextureAccess fNoiseAccess;
585 SkPerlinNoiseShader::PaintingData *fPaintingData;
588 typedef GrFragmentProcessor INHERITED;
591 /////////////////////////////////////////////////////////////////////
592 GR_DEFINE_FRAGMENT_PROCESSOR_TEST(GrPerlinNoiseEffect);
594 const GrFragmentProcessor* GrPerlinNoiseEffect::TestCreate(GrProcessorTestData* d) {
595 int numOctaves = d->fRandom->nextRangeU(2, 10);
596 bool stitchTiles = d->fRandom->nextBool();
597 SkScalar seed = SkIntToScalar(d->fRandom->nextU());
598 SkISize tileSize = SkISize::Make(d->fRandom->nextRangeU(4, 4096),
599 d->fRandom->nextRangeU(4, 4096));
600 SkScalar baseFrequencyX = d->fRandom->nextRangeScalar(0.01f,
602 SkScalar baseFrequencyY = d->fRandom->nextRangeScalar(0.01f,
605 SkAutoTUnref<SkShader> shader(d->fRandom->nextBool() ?
606 SkPerlinNoiseShader::CreateFractalNoise(baseFrequencyX, baseFrequencyY, numOctaves, seed,
607 stitchTiles ? &tileSize : nullptr) :
608 SkPerlinNoiseShader::CreateTurbulence(baseFrequencyX, baseFrequencyY, numOctaves, seed,
609 stitchTiles ? &tileSize : nullptr));
612 return shader->asFragmentProcessor(d->fContext,
613 GrTest::TestMatrix(d->fRandom), nullptr,
614 kNone_SkFilterQuality);
617 GrGLPerlinNoise::GrGLPerlinNoise(const GrProcessor& processor)
618 : fType(processor.cast<GrPerlinNoiseEffect>().type())
619 , fStitchTiles(processor.cast<GrPerlinNoiseEffect>().stitchTiles())
620 , fNumOctaves(processor.cast<GrPerlinNoiseEffect>().numOctaves()) {
623 void GrGLPerlinNoise::emitCode(EmitArgs& args) {
624 GrGLSLFragmentBuilder* fsBuilder = args.fBuilder->getFragmentShaderBuilder();
625 SkString vCoords = fsBuilder->ensureFSCoords2D(args.fCoords, 0);
627 fBaseFrequencyUni = args.fBuilder->addUniform(GrGLSLProgramBuilder::kFragment_Visibility,
628 kVec2f_GrSLType, kDefault_GrSLPrecision,
630 const char* baseFrequencyUni = args.fBuilder->getUniformCStr(fBaseFrequencyUni);
632 const char* stitchDataUni = nullptr;
634 fStitchDataUni = args.fBuilder->addUniform(GrGLSLProgramBuilder::kFragment_Visibility,
635 kVec2f_GrSLType, kDefault_GrSLPrecision,
637 stitchDataUni = args.fBuilder->getUniformCStr(fStitchDataUni);
640 // There are 4 lines, so the center of each line is 1/8, 3/8, 5/8 and 7/8
641 const char* chanCoordR = "0.125";
642 const char* chanCoordG = "0.375";
643 const char* chanCoordB = "0.625";
644 const char* chanCoordA = "0.875";
645 const char* chanCoord = "chanCoord";
646 const char* stitchData = "stitchData";
647 const char* ratio = "ratio";
648 const char* noiseVec = "noiseVec";
649 const char* noiseSmooth = "noiseSmooth";
650 const char* floorVal = "floorVal";
651 const char* fractVal = "fractVal";
652 const char* uv = "uv";
653 const char* ab = "ab";
654 const char* latticeIdx = "latticeIdx";
655 const char* bcoords = "bcoords";
656 const char* lattice = "lattice";
657 const char* inc8bit = "0.00390625"; // 1.0 / 256.0
658 // This is the math to convert the two 16bit integer packed into rgba 8 bit input into a
659 // [-1,1] vector and perform a dot product between that vector and the provided vector.
660 const char* dotLattice = "dot(((%s.ga + %s.rb * vec2(%s)) * vec2(2.0) - vec2(1.0)), %s);";
662 // Add noise function
663 static const GrGLSLShaderVar gPerlinNoiseArgs[] = {
664 GrGLSLShaderVar(chanCoord, kFloat_GrSLType),
665 GrGLSLShaderVar(noiseVec, kVec2f_GrSLType)
668 static const GrGLSLShaderVar gPerlinNoiseStitchArgs[] = {
669 GrGLSLShaderVar(chanCoord, kFloat_GrSLType),
670 GrGLSLShaderVar(noiseVec, kVec2f_GrSLType),
671 GrGLSLShaderVar(stitchData, kVec2f_GrSLType)
676 noiseCode.appendf("\tvec4 %s;\n", floorVal);
677 noiseCode.appendf("\t%s.xy = floor(%s);\n", floorVal, noiseVec);
678 noiseCode.appendf("\t%s.zw = %s.xy + vec2(1.0);\n", floorVal, floorVal);
679 noiseCode.appendf("\tvec2 %s = fract(%s);\n", fractVal, noiseVec);
681 // smooth curve : t * t * (3 - 2 * t)
682 noiseCode.appendf("\n\tvec2 %s = %s * %s * (vec2(3.0) - vec2(2.0) * %s);",
683 noiseSmooth, fractVal, fractVal, fractVal);
685 // Adjust frequencies if we're stitching tiles
687 noiseCode.appendf("\n\tif(%s.x >= %s.x) { %s.x -= %s.x; }",
688 floorVal, stitchData, floorVal, stitchData);
689 noiseCode.appendf("\n\tif(%s.y >= %s.y) { %s.y -= %s.y; }",
690 floorVal, stitchData, floorVal, stitchData);
691 noiseCode.appendf("\n\tif(%s.z >= %s.x) { %s.z -= %s.x; }",
692 floorVal, stitchData, floorVal, stitchData);
693 noiseCode.appendf("\n\tif(%s.w >= %s.y) { %s.w -= %s.y; }",
694 floorVal, stitchData, floorVal, stitchData);
697 // Get texture coordinates and normalize
698 noiseCode.appendf("\n\t%s = fract(floor(mod(%s, 256.0)) / vec4(256.0));\n",
701 // Get permutation for x
703 SkString xCoords("");
704 xCoords.appendf("vec2(%s.x, 0.5)", floorVal);
706 noiseCode.appendf("\n\tvec2 %s;\n\t%s.x = ", latticeIdx, latticeIdx);
707 fsBuilder->appendTextureLookup(&noiseCode, args.fSamplers[0], xCoords.c_str(),
709 noiseCode.append(".r;");
712 // Get permutation for x + 1
714 SkString xCoords("");
715 xCoords.appendf("vec2(%s.z, 0.5)", floorVal);
717 noiseCode.appendf("\n\t%s.y = ", latticeIdx);
718 fsBuilder->appendTextureLookup(&noiseCode, args.fSamplers[0], xCoords.c_str(),
720 noiseCode.append(".r;");
723 #if defined(SK_BUILD_FOR_ANDROID)
724 // Android rounding for Tegra devices, like, for example: Xoom (Tegra 2), Nexus 7 (Tegra 3).
725 // The issue is that colors aren't accurate enough on Tegra devices. For example, if an 8 bit
726 // value of 124 (or 0.486275 here) is entered, we can get a texture value of 123.513725
727 // (or 0.484368 here). The following rounding operation prevents these precision issues from
728 // affecting the result of the noise by making sure that we only have multiples of 1/255.
729 // (Note that 1/255 is about 0.003921569, which is the value used here).
730 noiseCode.appendf("\n\t%s = floor(%s * vec2(255.0) + vec2(0.5)) * vec2(0.003921569);",
731 latticeIdx, latticeIdx);
734 // Get (x,y) coordinates with the permutated x
735 noiseCode.appendf("\n\tvec4 %s = fract(%s.xyxy + %s.yyww);", bcoords, latticeIdx, floorVal);
737 noiseCode.appendf("\n\n\tvec2 %s;", uv);
738 // Compute u, at offset (0,0)
740 SkString latticeCoords("");
741 latticeCoords.appendf("vec2(%s.x, %s)", bcoords, chanCoord);
742 noiseCode.appendf("\n\tvec4 %s = ", lattice);
743 fsBuilder->appendTextureLookup(&noiseCode, args.fSamplers[1], latticeCoords.c_str(),
745 noiseCode.appendf(".bgra;\n\t%s.x = ", uv);
746 noiseCode.appendf(dotLattice, lattice, lattice, inc8bit, fractVal);
749 noiseCode.appendf("\n\t%s.x -= 1.0;", fractVal);
750 // Compute v, at offset (-1,0)
752 SkString latticeCoords("");
753 latticeCoords.appendf("vec2(%s.y, %s)", bcoords, chanCoord);
754 noiseCode.append("\n\tlattice = ");
755 fsBuilder->appendTextureLookup(&noiseCode, args.fSamplers[1], latticeCoords.c_str(),
757 noiseCode.appendf(".bgra;\n\t%s.y = ", uv);
758 noiseCode.appendf(dotLattice, lattice, lattice, inc8bit, fractVal);
761 // Compute 'a' as a linear interpolation of 'u' and 'v'
762 noiseCode.appendf("\n\tvec2 %s;", ab);
763 noiseCode.appendf("\n\t%s.x = mix(%s.x, %s.y, %s.x);", ab, uv, uv, noiseSmooth);
765 noiseCode.appendf("\n\t%s.y -= 1.0;", fractVal);
766 // Compute v, at offset (-1,-1)
768 SkString latticeCoords("");
769 latticeCoords.appendf("vec2(%s.w, %s)", bcoords, chanCoord);
770 noiseCode.append("\n\tlattice = ");
771 fsBuilder->appendTextureLookup(&noiseCode, args.fSamplers[1], latticeCoords.c_str(),
773 noiseCode.appendf(".bgra;\n\t%s.y = ", uv);
774 noiseCode.appendf(dotLattice, lattice, lattice, inc8bit, fractVal);
777 noiseCode.appendf("\n\t%s.x += 1.0;", fractVal);
778 // Compute u, at offset (0,-1)
780 SkString latticeCoords("");
781 latticeCoords.appendf("vec2(%s.z, %s)", bcoords, chanCoord);
782 noiseCode.append("\n\tlattice = ");
783 fsBuilder->appendTextureLookup(&noiseCode, args.fSamplers[1], latticeCoords.c_str(),
785 noiseCode.appendf(".bgra;\n\t%s.x = ", uv);
786 noiseCode.appendf(dotLattice, lattice, lattice, inc8bit, fractVal);
789 // Compute 'b' as a linear interpolation of 'u' and 'v'
790 noiseCode.appendf("\n\t%s.y = mix(%s.x, %s.y, %s.x);", ab, uv, uv, noiseSmooth);
791 // Compute the noise as a linear interpolation of 'a' and 'b'
792 noiseCode.appendf("\n\treturn mix(%s.x, %s.y, %s.y);\n", ab, ab, noiseSmooth);
794 SkString noiseFuncName;
796 fsBuilder->emitFunction(kFloat_GrSLType,
797 "perlinnoise", SK_ARRAY_COUNT(gPerlinNoiseStitchArgs),
798 gPerlinNoiseStitchArgs, noiseCode.c_str(), &noiseFuncName);
800 fsBuilder->emitFunction(kFloat_GrSLType,
801 "perlinnoise", SK_ARRAY_COUNT(gPerlinNoiseArgs),
802 gPerlinNoiseArgs, noiseCode.c_str(), &noiseFuncName);
805 // There are rounding errors if the floor operation is not performed here
806 fsBuilder->codeAppendf("\n\t\tvec2 %s = floor(%s.xy) * %s;",
807 noiseVec, vCoords.c_str(), baseFrequencyUni);
809 // Clear the color accumulator
810 fsBuilder->codeAppendf("\n\t\t%s = vec4(0.0);", args.fOutputColor);
813 // Set up TurbulenceInitial stitch values.
814 fsBuilder->codeAppendf("\n\t\tvec2 %s = %s;", stitchData, stitchDataUni);
817 fsBuilder->codeAppendf("\n\t\tfloat %s = 1.0;", ratio);
819 // Loop over all octaves
820 fsBuilder->codeAppendf("\n\t\tfor (int octave = 0; octave < %d; ++octave) {", fNumOctaves);
822 fsBuilder->codeAppendf("\n\t\t\t%s += ", args.fOutputColor);
823 if (fType != SkPerlinNoiseShader::kFractalNoise_Type) {
824 fsBuilder->codeAppend("abs(");
827 fsBuilder->codeAppendf(
828 "vec4(\n\t\t\t\t%s(%s, %s, %s),\n\t\t\t\t%s(%s, %s, %s),"
829 "\n\t\t\t\t%s(%s, %s, %s),\n\t\t\t\t%s(%s, %s, %s))",
830 noiseFuncName.c_str(), chanCoordR, noiseVec, stitchData,
831 noiseFuncName.c_str(), chanCoordG, noiseVec, stitchData,
832 noiseFuncName.c_str(), chanCoordB, noiseVec, stitchData,
833 noiseFuncName.c_str(), chanCoordA, noiseVec, stitchData);
835 fsBuilder->codeAppendf(
836 "vec4(\n\t\t\t\t%s(%s, %s),\n\t\t\t\t%s(%s, %s),"
837 "\n\t\t\t\t%s(%s, %s),\n\t\t\t\t%s(%s, %s))",
838 noiseFuncName.c_str(), chanCoordR, noiseVec,
839 noiseFuncName.c_str(), chanCoordG, noiseVec,
840 noiseFuncName.c_str(), chanCoordB, noiseVec,
841 noiseFuncName.c_str(), chanCoordA, noiseVec);
843 if (fType != SkPerlinNoiseShader::kFractalNoise_Type) {
844 fsBuilder->codeAppendf(")"); // end of "abs("
846 fsBuilder->codeAppendf(" * %s;", ratio);
848 fsBuilder->codeAppendf("\n\t\t\t%s *= vec2(2.0);", noiseVec);
849 fsBuilder->codeAppendf("\n\t\t\t%s *= 0.5;", ratio);
852 fsBuilder->codeAppendf("\n\t\t\t%s *= vec2(2.0);", stitchData);
854 fsBuilder->codeAppend("\n\t\t}"); // end of the for loop on octaves
856 if (fType == SkPerlinNoiseShader::kFractalNoise_Type) {
857 // The value of turbulenceFunctionResult comes from ((turbulenceFunctionResult) + 1) / 2
858 // by fractalNoise and (turbulenceFunctionResult) by turbulence.
859 fsBuilder->codeAppendf("\n\t\t%s = %s * vec4(0.5) + vec4(0.5);",
860 args.fOutputColor,args.fOutputColor);
864 fsBuilder->codeAppendf("\n\t\t%s = clamp(%s, 0.0, 1.0);", args.fOutputColor, args.fOutputColor);
866 // Pre-multiply the result
867 fsBuilder->codeAppendf("\n\t\t%s = vec4(%s.rgb * %s.aaa, %s.a);\n",
868 args.fOutputColor, args.fOutputColor,
869 args.fOutputColor, args.fOutputColor);
872 void GrGLPerlinNoise::GenKey(const GrProcessor& processor, const GrGLSLCaps&,
873 GrProcessorKeyBuilder* b) {
874 const GrPerlinNoiseEffect& turbulence = processor.cast<GrPerlinNoiseEffect>();
876 uint32_t key = turbulence.numOctaves();
878 key = key << 3; // Make room for next 3 bits
880 switch (turbulence.type()) {
881 case SkPerlinNoiseShader::kFractalNoise_Type:
884 case SkPerlinNoiseShader::kTurbulence_Type:
892 if (turbulence.stitchTiles()) {
893 key |= 0x4; // Flip the 3rd bit if tile stitching is on
899 void GrGLPerlinNoise::onSetData(const GrGLSLProgramDataManager& pdman,
900 const GrProcessor& processor) {
901 INHERITED::onSetData(pdman, processor);
903 const GrPerlinNoiseEffect& turbulence = processor.cast<GrPerlinNoiseEffect>();
905 const SkVector& baseFrequency = turbulence.baseFrequency();
906 pdman.set2f(fBaseFrequencyUni, baseFrequency.fX, baseFrequency.fY);
908 if (turbulence.stitchTiles()) {
909 const SkPerlinNoiseShader::StitchData& stitchData = turbulence.stitchData();
910 pdman.set2f(fStitchDataUni, SkIntToScalar(stitchData.fWidth),
911 SkIntToScalar(stitchData.fHeight));
915 /////////////////////////////////////////////////////////////////////
916 const GrFragmentProcessor* SkPerlinNoiseShader::asFragmentProcessor(
918 const SkMatrix& viewM,
919 const SkMatrix* externalLocalMatrix,
920 SkFilterQuality) const {
923 SkMatrix localMatrix = this->getLocalMatrix();
924 if (externalLocalMatrix) {
925 localMatrix.preConcat(*externalLocalMatrix);
928 SkMatrix matrix = viewM;
929 matrix.preConcat(localMatrix);
931 if (0 == fNumOctaves) {
932 if (kFractalNoise_Type == fType) {
933 // Extract the incoming alpha and emit rgba = (a/4, a/4, a/4, a/2)
934 SkAutoTUnref<const GrFragmentProcessor> inner(
935 GrConstColorProcessor::Create(0x80404040,
936 GrConstColorProcessor::kModulateRGBA_InputMode));
937 return GrFragmentProcessor::MulOutputByInputAlpha(inner);
940 return GrConstColorProcessor::Create(0x0, GrConstColorProcessor::kIgnore_InputMode);
943 // Either we don't stitch tiles, either we have a valid tile size
944 SkASSERT(!fStitchTiles || !fTileSize.isEmpty());
946 SkPerlinNoiseShader::PaintingData* paintingData =
947 new PaintingData(fTileSize, fSeed, fBaseFrequencyX, fBaseFrequencyY, matrix);
948 SkAutoTUnref<GrTexture> permutationsTexture(
949 GrRefCachedBitmapTexture(context, paintingData->getPermutationsBitmap(),
950 GrTextureParams::ClampNoFilter()));
951 SkAutoTUnref<GrTexture> noiseTexture(
952 GrRefCachedBitmapTexture(context, paintingData->getNoiseBitmap(),
953 GrTextureParams::ClampNoFilter()));
956 m.setTranslateX(-localMatrix.getTranslateX() + SK_Scalar1);
957 m.setTranslateY(-localMatrix.getTranslateY() + SK_Scalar1);
958 if ((permutationsTexture) && (noiseTexture)) {
959 SkAutoTUnref<GrFragmentProcessor> inner(
960 GrPerlinNoiseEffect::Create(fType,
964 permutationsTexture, noiseTexture,
966 return GrFragmentProcessor::MulOutputByInputAlpha(inner);
974 #ifndef SK_IGNORE_TO_STRING
975 void SkPerlinNoiseShader::toString(SkString* str) const {
976 str->append("SkPerlinNoiseShader: (");
978 str->append("type: ");
980 case kFractalNoise_Type:
981 str->append("\"fractal noise\"");
983 case kTurbulence_Type:
984 str->append("\"turbulence\"");
987 str->append("\"unknown\"");
990 str->append(" base frequency: (");
991 str->appendScalar(fBaseFrequencyX);
993 str->appendScalar(fBaseFrequencyY);
994 str->append(") number of octaves: ");
995 str->appendS32(fNumOctaves);
996 str->append(" seed: ");
997 str->appendScalar(fSeed);
998 str->append(" stitch tiles: ");
999 str->append(fStitchTiles ? "true " : "false ");
1001 this->INHERITED::toString(str);