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 "include/effects/SkPerlinNoiseShader.h"
9
10 #include "include/core/SkBitmap.h"
11 #include "include/core/SkColorFilter.h"
12 #include "include/core/SkShader.h"
13 #include "include/core/SkString.h"
14 #include "include/core/SkUnPreMultiply.h"
15 #include "include/private/base/SkTPin.h"
16 #include "src/base/SkArenaAlloc.h"
17 #include "src/core/SkMatrixProvider.h"
18 #include "src/core/SkReadBuffer.h"
19 #include "src/core/SkVM.h"
20 #include "src/core/SkWriteBuffer.h"
21
22 #if defined(SK_GANESH)
23 #include "include/gpu/GrRecordingContext.h"
24 #include "src/gpu/KeyBuilder.h"
25 #include "src/gpu/ganesh/GrFPArgs.h"
26 #include "src/gpu/ganesh/GrFragmentProcessor.h"
27 #include "src/gpu/ganesh/GrProcessorUnitTest.h"
28 #include "src/gpu/ganesh/GrRecordingContextPriv.h"
29 #include "src/gpu/ganesh/SkGr.h"
30 #include "src/gpu/ganesh/effects/GrMatrixEffect.h"
31 #include "src/gpu/ganesh/effects/GrTextureEffect.h"
32 #include "src/gpu/ganesh/glsl/GrGLSLFragmentShaderBuilder.h"
33 #include "src/gpu/ganesh/glsl/GrGLSLProgramDataManager.h"
34 #include "src/gpu/ganesh/glsl/GrGLSLUniformHandler.h"
35 #endif
36
37 static const int kBlockSize = 256;
38 static const int kBlockMask = kBlockSize - 1;
39 static const int kPerlinNoise = 4096;
40 static const int kRandMaximum = SK_MaxS32; // 2**31 - 1
41
42 class SkPerlinNoiseShaderImpl : public SkShaderBase {
43 public:
44 struct StitchData {
StitchDataSkPerlinNoiseShaderImpl::StitchData45 StitchData()
46 : fWidth(0)
47 , fWrapX(0)
48 , fHeight(0)
49 , fWrapY(0)
50 {}
51
StitchDataSkPerlinNoiseShaderImpl::StitchData52 StitchData(SkScalar w, SkScalar h)
53 : fWidth(std::min(SkScalarRoundToInt(w), SK_MaxS32 - kPerlinNoise))
54 , fWrapX(kPerlinNoise + fWidth)
55 , fHeight(std::min(SkScalarRoundToInt(h), SK_MaxS32 - kPerlinNoise))
56 , fWrapY(kPerlinNoise + fHeight) {}
57
operator ==SkPerlinNoiseShaderImpl::StitchData58 bool operator==(const StitchData& other) const {
59 return fWidth == other.fWidth &&
60 fWrapX == other.fWrapX &&
61 fHeight == other.fHeight &&
62 fWrapY == other.fWrapY;
63 }
64
65 int fWidth; // How much to subtract to wrap for stitching.
66 int fWrapX; // Minimum value to wrap.
67 int fHeight;
68 int fWrapY;
69 };
70
71 struct PaintingData {
PaintingDataSkPerlinNoiseShaderImpl::PaintingData72 PaintingData(const SkISize& tileSize, SkScalar seed,
73 SkScalar baseFrequencyX, SkScalar baseFrequencyY,
74 const SkMatrix& matrix)
75 {
76 SkVector tileVec;
77 matrix.mapVector(SkIntToScalar(tileSize.fWidth), SkIntToScalar(tileSize.fHeight),
78 &tileVec);
79
80 SkSize scale;
81 if (!matrix.decomposeScale(&scale, nullptr)) {
82 scale.set(SK_ScalarNearlyZero, SK_ScalarNearlyZero);
83 }
84 fBaseFrequency.set(baseFrequencyX * SkScalarInvert(scale.width()),
85 baseFrequencyY * SkScalarInvert(scale.height()));
86 fTileSize.set(SkScalarRoundToInt(tileVec.fX), SkScalarRoundToInt(tileVec.fY));
87 this->init(seed);
88 if (!fTileSize.isEmpty()) {
89 this->stitch();
90 }
91
92 #if defined(SK_GANESH)
93 SkImageInfo info = SkImageInfo::MakeA8(kBlockSize, 1);
94 fPermutationsBitmap.installPixels(info, fLatticeSelector, info.minRowBytes());
95 fPermutationsBitmap.setImmutable();
96
97 info = SkImageInfo::Make(kBlockSize, 4, kRGBA_8888_SkColorType, kPremul_SkAlphaType);
98 fNoiseBitmap.installPixels(info, fNoise[0][0], info.minRowBytes());
99 fNoiseBitmap.setImmutable();
100 #endif
101 }
102
103 #if defined(SK_GANESH)
PaintingDataSkPerlinNoiseShaderImpl::PaintingData104 PaintingData(const PaintingData& that)
105 : fSeed(that.fSeed)
106 , fTileSize(that.fTileSize)
107 , fBaseFrequency(that.fBaseFrequency)
108 , fStitchDataInit(that.fStitchDataInit)
109 , fPermutationsBitmap(that.fPermutationsBitmap)
110 , fNoiseBitmap(that.fNoiseBitmap) {
111 memcpy(fLatticeSelector, that.fLatticeSelector, sizeof(fLatticeSelector));
112 memcpy(fNoise, that.fNoise, sizeof(fNoise));
113 memcpy(fGradient, that.fGradient, sizeof(fGradient));
114 }
115 #endif
116
117 int fSeed;
118 uint8_t fLatticeSelector[kBlockSize];
119 uint16_t fNoise[4][kBlockSize][2];
120 SkPoint fGradient[4][kBlockSize];
121 SkISize fTileSize;
122 SkVector fBaseFrequency;
123 StitchData fStitchDataInit;
124
125 private:
126
127 #if defined(SK_GANESH)
128 SkBitmap fPermutationsBitmap;
129 SkBitmap fNoiseBitmap;
130 #endif
131
randomSkPerlinNoiseShaderImpl::PaintingData132 inline int random() {
133 // See https://www.w3.org/TR/SVG11/filters.html#feTurbulenceElement
134 // m = kRandMaximum, 2**31 - 1 (2147483647)
135 static constexpr int kRandAmplitude = 16807; // 7**5; primitive root of m
136 static constexpr int kRandQ = 127773; // m / a
137 static constexpr int kRandR = 2836; // m % a
138
139 int result = kRandAmplitude * (fSeed % kRandQ) - kRandR * (fSeed / kRandQ);
140 if (result <= 0) {
141 result += kRandMaximum;
142 }
143 fSeed = result;
144 return result;
145 }
146
147 // Only called once. Could be part of the constructor.
initSkPerlinNoiseShaderImpl::PaintingData148 void init(SkScalar seed)
149 {
150 // According to the SVG spec, we must truncate (not round) the seed value.
151 fSeed = SkScalarTruncToInt(seed);
152 // The seed value clamp to the range [1, kRandMaximum - 1].
153 if (fSeed <= 0) {
154 fSeed = -(fSeed % (kRandMaximum - 1)) + 1;
155 }
156 if (fSeed > kRandMaximum - 1) {
157 fSeed = kRandMaximum - 1;
158 }
159 for (int channel = 0; channel < 4; ++channel) {
160 for (int i = 0; i < kBlockSize; ++i) {
161 fLatticeSelector[i] = i;
162 fNoise[channel][i][0] = (random() % (2 * kBlockSize));
163 fNoise[channel][i][1] = (random() % (2 * kBlockSize));
164 }
165 }
166 for (int i = kBlockSize - 1; i > 0; --i) {
167 int k = fLatticeSelector[i];
168 int j = random() % kBlockSize;
169 SkASSERT(j >= 0);
170 SkASSERT(j < kBlockSize);
171 fLatticeSelector[i] = fLatticeSelector[j];
172 fLatticeSelector[j] = k;
173 }
174
175 // Perform the permutations now
176 {
177 // Copy noise data
178 uint16_t noise[4][kBlockSize][2];
179 for (int i = 0; i < kBlockSize; ++i) {
180 for (int channel = 0; channel < 4; ++channel) {
181 for (int j = 0; j < 2; ++j) {
182 noise[channel][i][j] = fNoise[channel][i][j];
183 }
184 }
185 }
186 // Do permutations on noise data
187 for (int i = 0; i < kBlockSize; ++i) {
188 for (int channel = 0; channel < 4; ++channel) {
189 for (int j = 0; j < 2; ++j) {
190 fNoise[channel][i][j] = noise[channel][fLatticeSelector[i]][j];
191 }
192 }
193 }
194 }
195
196 // Half of the largest possible value for 16 bit unsigned int
197 static constexpr SkScalar kHalfMax16bits = 32767.5f;
198
199 // Compute gradients from permutated noise data
200 static constexpr SkScalar kInvBlockSizef = 1.0 / SkIntToScalar(kBlockSize);
201 for (int channel = 0; channel < 4; ++channel) {
202 for (int i = 0; i < kBlockSize; ++i) {
203 fGradient[channel][i] = SkPoint::Make(
204 (fNoise[channel][i][0] - kBlockSize) * kInvBlockSizef,
205 (fNoise[channel][i][1] - kBlockSize) * kInvBlockSizef);
206 fGradient[channel][i].normalize();
207 // Put the normalized gradient back into the noise data
208 fNoise[channel][i][0] =
209 SkScalarRoundToInt((fGradient[channel][i].fX + 1) * kHalfMax16bits);
210 fNoise[channel][i][1] =
211 SkScalarRoundToInt((fGradient[channel][i].fY + 1) * kHalfMax16bits);
212 }
213 }
214 }
215
216 // Only called once. Could be part of the constructor.
stitchSkPerlinNoiseShaderImpl::PaintingData217 void stitch() {
218 SkScalar tileWidth = SkIntToScalar(fTileSize.width());
219 SkScalar tileHeight = SkIntToScalar(fTileSize.height());
220 SkASSERT(tileWidth > 0 && tileHeight > 0);
221 // When stitching tiled turbulence, the frequencies must be adjusted
222 // so that the tile borders will be continuous.
223 if (fBaseFrequency.fX) {
224 SkScalar lowFrequencx =
225 SkScalarFloorToScalar(tileWidth * fBaseFrequency.fX) / tileWidth;
226 SkScalar highFrequencx =
227 SkScalarCeilToScalar(tileWidth * fBaseFrequency.fX) / tileWidth;
228 // BaseFrequency should be non-negative according to the standard.
229 // lowFrequencx can be 0 if fBaseFrequency.fX is very small.
230 if (sk_ieee_float_divide(fBaseFrequency.fX, lowFrequencx) < highFrequencx / fBaseFrequency.fX) {
231 fBaseFrequency.fX = lowFrequencx;
232 } else {
233 fBaseFrequency.fX = highFrequencx;
234 }
235 }
236 if (fBaseFrequency.fY) {
237 SkScalar lowFrequency =
238 SkScalarFloorToScalar(tileHeight * fBaseFrequency.fY) / tileHeight;
239 SkScalar highFrequency =
240 SkScalarCeilToScalar(tileHeight * fBaseFrequency.fY) / tileHeight;
241 // lowFrequency can be 0 if fBaseFrequency.fY is very small.
242 if (sk_ieee_float_divide(fBaseFrequency.fY, lowFrequency) < highFrequency / fBaseFrequency.fY) {
243 fBaseFrequency.fY = lowFrequency;
244 } else {
245 fBaseFrequency.fY = highFrequency;
246 }
247 }
248 // Set up TurbulenceInitial stitch values.
249 fStitchDataInit = StitchData(tileWidth * fBaseFrequency.fX,
250 tileHeight * fBaseFrequency.fY);
251 }
252
253 public:
254
255 #if defined(SK_GANESH)
getPermutationsBitmapSkPerlinNoiseShaderImpl::PaintingData256 const SkBitmap& getPermutationsBitmap() const { return fPermutationsBitmap; }
257
getNoiseBitmapSkPerlinNoiseShaderImpl::PaintingData258 const SkBitmap& getNoiseBitmap() const { return fNoiseBitmap; }
259 #endif
260 };
261
262 /**
263 * About the noise types : the difference between the first 2 is just minor tweaks to the
264 * algorithm, they're not 2 entirely different noises. The output looks different, but once the
265 * noise is generated in the [1, -1] range, the output is brought back in the [0, 1] range by
266 * doing :
267 * kFractalNoise_Type : noise * 0.5 + 0.5
268 * kTurbulence_Type : abs(noise)
269 * Very little differences between the 2 types, although you can tell the difference visually.
270 */
271 enum Type {
272 kFractalNoise_Type,
273 kTurbulence_Type,
274 kLast_Type = kTurbulence_Type
275 };
276
277 static const int kMaxOctaves = 255; // numOctaves must be <= 0 and <= kMaxOctaves
278
279 SkPerlinNoiseShaderImpl(SkPerlinNoiseShaderImpl::Type type, SkScalar baseFrequencyX,
280 SkScalar baseFrequencyY, int numOctaves, SkScalar seed,
281 const SkISize* tileSize);
282
283 class PerlinNoiseShaderContext : public Context {
284 public:
285 PerlinNoiseShaderContext(const SkPerlinNoiseShaderImpl& shader, const ContextRec&);
286
287 void shadeSpan(int x, int y, SkPMColor[], int count) override;
288
289 private:
290 SkPMColor shade(const SkPoint& point, StitchData& stitchData) const;
291 SkScalar calculateTurbulenceValueForPoint(
292 int channel,
293 StitchData& stitchData, const SkPoint& point) const;
294 SkScalar noise2D(int channel,
295 const StitchData& stitchData, const SkPoint& noiseVector) const;
296
297 SkMatrix fMatrix;
298 PaintingData fPaintingData;
299
300 using INHERITED = Context;
301 };
302
303 #if defined(SK_GANESH)
304 std::unique_ptr<GrFragmentProcessor> asFragmentProcessor(const GrFPArgs&,
305 const MatrixRec&) const override;
306 #endif
307
program(skvm::Builder *,skvm::Coord,skvm::Coord,skvm::Color,const MatrixRec &,const SkColorInfo &,skvm::Uniforms *,SkArenaAlloc *) const308 skvm::Color program(skvm::Builder*,
309 skvm::Coord,
310 skvm::Coord,
311 skvm::Color,
312 const MatrixRec&,
313 const SkColorInfo&,
314 skvm::Uniforms*,
315 SkArenaAlloc*) const override {
316 // TODO?
317 return {};
318 }
319
320 protected:
321 void flatten(SkWriteBuffer&) const override;
322 #ifdef SK_ENABLE_LEGACY_SHADERCONTEXT
323 Context* onMakeContext(const ContextRec&, SkArenaAlloc*) const override;
324 #endif
325
326 private:
327 SK_FLATTENABLE_HOOKS(SkPerlinNoiseShaderImpl)
328
329 const SkPerlinNoiseShaderImpl::Type fType;
330 const SkScalar fBaseFrequencyX;
331 const SkScalar fBaseFrequencyY;
332 const int fNumOctaves;
333 const SkScalar fSeed;
334 const SkISize fTileSize;
335 const bool fStitchTiles;
336
337 friend class ::SkPerlinNoiseShader;
338
339 using INHERITED = SkShaderBase;
340 };
341
342 namespace {
343
344 // noiseValue is the color component's value (or color)
345 // limitValue is the maximum perlin noise array index value allowed
346 // newValue is the current noise dimension (either width or height)
checkNoise(int noiseValue,int limitValue,int newValue)347 inline int checkNoise(int noiseValue, int limitValue, int newValue) {
348 // If the noise value would bring us out of bounds of the current noise array while we are
349 // stiching noise tiles together, wrap the noise around the current dimension of the noise to
350 // stay within the array bounds in a continuous fashion (so that tiling lines are not visible)
351 if (noiseValue >= limitValue) {
352 noiseValue -= newValue;
353 }
354 return noiseValue;
355 }
356
smoothCurve(SkScalar t)357 inline SkScalar smoothCurve(SkScalar t) {
358 return t * t * (3 - 2 * t);
359 }
360
361 } // end namespace
362
SkPerlinNoiseShaderImpl(SkPerlinNoiseShaderImpl::Type type,SkScalar baseFrequencyX,SkScalar baseFrequencyY,int numOctaves,SkScalar seed,const SkISize * tileSize)363 SkPerlinNoiseShaderImpl::SkPerlinNoiseShaderImpl(SkPerlinNoiseShaderImpl::Type type,
364 SkScalar baseFrequencyX,
365 SkScalar baseFrequencyY,
366 int numOctaves,
367 SkScalar seed,
368 const SkISize* tileSize)
369 : fType(type)
370 , fBaseFrequencyX(baseFrequencyX)
371 , fBaseFrequencyY(baseFrequencyY)
372 , fNumOctaves(numOctaves > kMaxOctaves ? kMaxOctaves : numOctaves/*[0,255] octaves allowed*/)
373 , fSeed(seed)
374 , fTileSize(nullptr == tileSize ? SkISize::Make(0, 0) : *tileSize)
375 , fStitchTiles(!fTileSize.isEmpty())
376 {
377 SkASSERT(numOctaves >= 0 && numOctaves <= kMaxOctaves);
378 SkASSERT(fBaseFrequencyX >= 0);
379 SkASSERT(fBaseFrequencyY >= 0);
380 }
381
CreateProc(SkReadBuffer & buffer)382 sk_sp<SkFlattenable> SkPerlinNoiseShaderImpl::CreateProc(SkReadBuffer& buffer) {
383 Type type = buffer.read32LE(kLast_Type);
384
385 SkScalar freqX = buffer.readScalar();
386 SkScalar freqY = buffer.readScalar();
387 int octaves = buffer.read32LE<int>(kMaxOctaves);
388
389 SkScalar seed = buffer.readScalar();
390 SkISize tileSize;
391 tileSize.fWidth = buffer.readInt();
392 tileSize.fHeight = buffer.readInt();
393
394 switch (type) {
395 case kFractalNoise_Type:
396 return SkPerlinNoiseShader::MakeFractalNoise(freqX, freqY, octaves, seed, &tileSize);
397 case kTurbulence_Type:
398 return SkPerlinNoiseShader::MakeTurbulence(freqX, freqY, octaves, seed, &tileSize);
399 default:
400 // Really shouldn't get here b.c. of earlier check on type
401 buffer.validate(false);
402 return nullptr;
403 }
404 }
405
flatten(SkWriteBuffer & buffer) const406 void SkPerlinNoiseShaderImpl::flatten(SkWriteBuffer& buffer) const {
407 buffer.writeInt((int) fType);
408 buffer.writeScalar(fBaseFrequencyX);
409 buffer.writeScalar(fBaseFrequencyY);
410 buffer.writeInt(fNumOctaves);
411 buffer.writeScalar(fSeed);
412 buffer.writeInt(fTileSize.fWidth);
413 buffer.writeInt(fTileSize.fHeight);
414 }
415
noise2D(int channel,const StitchData & stitchData,const SkPoint & noiseVector) const416 SkScalar SkPerlinNoiseShaderImpl::PerlinNoiseShaderContext::noise2D(
417 int channel, const StitchData& stitchData, const SkPoint& noiseVector) const {
418 struct Noise {
419 int noisePositionIntegerValue;
420 int nextNoisePositionIntegerValue;
421 SkScalar noisePositionFractionValue;
422 Noise(SkScalar component)
423 {
424 SkScalar position = component + kPerlinNoise;
425 noisePositionIntegerValue = SkScalarFloorToInt(position);
426 noisePositionFractionValue = position - SkIntToScalar(noisePositionIntegerValue);
427 nextNoisePositionIntegerValue = noisePositionIntegerValue + 1;
428 }
429 };
430 Noise noiseX(noiseVector.x());
431 Noise noiseY(noiseVector.y());
432 SkScalar u, v;
433 const SkPerlinNoiseShaderImpl& perlinNoiseShader = static_cast<const SkPerlinNoiseShaderImpl&>(fShader);
434 // If stitching, adjust lattice points accordingly.
435 if (perlinNoiseShader.fStitchTiles) {
436 noiseX.noisePositionIntegerValue =
437 checkNoise(noiseX.noisePositionIntegerValue, stitchData.fWrapX, stitchData.fWidth);
438 noiseY.noisePositionIntegerValue =
439 checkNoise(noiseY.noisePositionIntegerValue, stitchData.fWrapY, stitchData.fHeight);
440 noiseX.nextNoisePositionIntegerValue =
441 checkNoise(noiseX.nextNoisePositionIntegerValue, stitchData.fWrapX, stitchData.fWidth);
442 noiseY.nextNoisePositionIntegerValue =
443 checkNoise(noiseY.nextNoisePositionIntegerValue, stitchData.fWrapY, stitchData.fHeight);
444 }
445 noiseX.noisePositionIntegerValue &= kBlockMask;
446 noiseY.noisePositionIntegerValue &= kBlockMask;
447 noiseX.nextNoisePositionIntegerValue &= kBlockMask;
448 noiseY.nextNoisePositionIntegerValue &= kBlockMask;
449 int i = fPaintingData.fLatticeSelector[noiseX.noisePositionIntegerValue];
450 int j = fPaintingData.fLatticeSelector[noiseX.nextNoisePositionIntegerValue];
451 int b00 = (i + noiseY.noisePositionIntegerValue) & kBlockMask;
452 int b10 = (j + noiseY.noisePositionIntegerValue) & kBlockMask;
453 int b01 = (i + noiseY.nextNoisePositionIntegerValue) & kBlockMask;
454 int b11 = (j + noiseY.nextNoisePositionIntegerValue) & kBlockMask;
455 SkScalar sx = smoothCurve(noiseX.noisePositionFractionValue);
456 SkScalar sy = smoothCurve(noiseY.noisePositionFractionValue);
457
458 if (sx < 0 || sy < 0 || sx > 1 || sy > 1) {
459 return 0; // Check for pathological inputs.
460 }
461
462 // This is taken 1:1 from SVG spec: http://www.w3.org/TR/SVG11/filters.html#feTurbulenceElement
463 SkPoint fractionValue = SkPoint::Make(noiseX.noisePositionFractionValue,
464 noiseY.noisePositionFractionValue); // Offset (0,0)
465 u = fPaintingData.fGradient[channel][b00].dot(fractionValue);
466 fractionValue.fX -= SK_Scalar1; // Offset (-1,0)
467 v = fPaintingData.fGradient[channel][b10].dot(fractionValue);
468 SkScalar a = SkScalarInterp(u, v, sx);
469 fractionValue.fY -= SK_Scalar1; // Offset (-1,-1)
470 v = fPaintingData.fGradient[channel][b11].dot(fractionValue);
471 fractionValue.fX = noiseX.noisePositionFractionValue; // Offset (0,-1)
472 u = fPaintingData.fGradient[channel][b01].dot(fractionValue);
473 SkScalar b = SkScalarInterp(u, v, sx);
474 return SkScalarInterp(a, b, sy);
475 }
476
calculateTurbulenceValueForPoint(int channel,StitchData & stitchData,const SkPoint & point) const477 SkScalar SkPerlinNoiseShaderImpl::PerlinNoiseShaderContext::calculateTurbulenceValueForPoint(
478 int channel, StitchData& stitchData, const SkPoint& point) const {
479 const SkPerlinNoiseShaderImpl& perlinNoiseShader = static_cast<const SkPerlinNoiseShaderImpl&>(fShader);
480 if (perlinNoiseShader.fStitchTiles) {
481 // Set up TurbulenceInitial stitch values.
482 stitchData = fPaintingData.fStitchDataInit;
483 }
484 SkScalar turbulenceFunctionResult = 0;
485 SkPoint noiseVector(SkPoint::Make(point.x() * fPaintingData.fBaseFrequency.fX,
486 point.y() * fPaintingData.fBaseFrequency.fY));
487 SkScalar ratio = SK_Scalar1;
488 for (int octave = 0; octave < perlinNoiseShader.fNumOctaves; ++octave) {
489 SkScalar noise = noise2D(channel, stitchData, noiseVector);
490 SkScalar numer = (perlinNoiseShader.fType == kFractalNoise_Type) ?
491 noise : SkScalarAbs(noise);
492 turbulenceFunctionResult += numer / ratio;
493 noiseVector.fX *= 2;
494 noiseVector.fY *= 2;
495 ratio *= 2;
496 if (perlinNoiseShader.fStitchTiles) {
497 // Update stitch values
498 stitchData = StitchData(SkIntToScalar(stitchData.fWidth) * 2,
499 SkIntToScalar(stitchData.fHeight) * 2);
500 }
501 }
502
503 // The value of turbulenceFunctionResult comes from ((turbulenceFunctionResult) + 1) / 2
504 // by fractalNoise and (turbulenceFunctionResult) by turbulence.
505 if (perlinNoiseShader.fType == kFractalNoise_Type) {
506 turbulenceFunctionResult = SkScalarHalf(turbulenceFunctionResult + 1);
507 }
508
509 if (channel == 3) { // Scale alpha by paint value
510 turbulenceFunctionResult *= SkIntToScalar(getPaintAlpha()) / 255;
511 }
512
513 // Clamp result
514 return SkTPin(turbulenceFunctionResult, 0.0f, SK_Scalar1);
515 }
516
517 ////////////////////////////////////////////////////////////////////////////////////////////////////
518
shade(const SkPoint & point,StitchData & stitchData) const519 SkPMColor SkPerlinNoiseShaderImpl::PerlinNoiseShaderContext::shade(
520 const SkPoint& point, StitchData& stitchData) const {
521 SkPoint newPoint;
522 fMatrix.mapPoints(&newPoint, &point, 1);
523 newPoint.fX = SkScalarRoundToScalar(newPoint.fX);
524 newPoint.fY = SkScalarRoundToScalar(newPoint.fY);
525
526 U8CPU rgba[4];
527 for (int channel = 3; channel >= 0; --channel) {
528 SkScalar value;
529 value = calculateTurbulenceValueForPoint(channel, stitchData, newPoint);
530 rgba[channel] = SkScalarFloorToInt(255 * value);
531 }
532 return SkPreMultiplyARGB(rgba[3], rgba[0], rgba[1], rgba[2]);
533 }
534
535 #ifdef SK_ENABLE_LEGACY_SHADERCONTEXT
onMakeContext(const ContextRec & rec,SkArenaAlloc * alloc) const536 SkShaderBase::Context* SkPerlinNoiseShaderImpl::onMakeContext(const ContextRec& rec,
537 SkArenaAlloc* alloc) const {
538 // should we pay attention to rec's device-colorspace?
539 return alloc->make<PerlinNoiseShaderContext>(*this, rec);
540 }
541 #endif
542
total_matrix(const SkShaderBase::ContextRec & rec,const SkShaderBase & shader)543 static inline SkMatrix total_matrix(const SkShaderBase::ContextRec& rec,
544 const SkShaderBase& shader) {
545 if (rec.fLocalMatrix) {
546 return SkMatrix::Concat(*rec.fMatrix, *rec.fLocalMatrix);
547 }
548 return *rec.fMatrix;
549 }
550
PerlinNoiseShaderContext(const SkPerlinNoiseShaderImpl & shader,const ContextRec & rec)551 SkPerlinNoiseShaderImpl::PerlinNoiseShaderContext::PerlinNoiseShaderContext(
552 const SkPerlinNoiseShaderImpl& shader, const ContextRec& rec)
553 : INHERITED(shader, rec)
554 , fMatrix(total_matrix(rec, shader)) // used for temp storage, adjusted below
555 , fPaintingData(shader.fTileSize, shader.fSeed, shader.fBaseFrequencyX,
556 shader.fBaseFrequencyY, fMatrix)
557 {
558 // This (1,1) translation is due to WebKit's 1 based coordinates for the noise
559 // (as opposed to 0 based, usually). The same adjustment is in the setData() function.
560 fMatrix.setTranslate(-fMatrix.getTranslateX() + SK_Scalar1,
561 -fMatrix.getTranslateY() + SK_Scalar1);
562 }
563
shadeSpan(int x,int y,SkPMColor result[],int count)564 void SkPerlinNoiseShaderImpl::PerlinNoiseShaderContext::shadeSpan(
565 int x, int y, SkPMColor result[], int count) {
566 SkPoint point = SkPoint::Make(SkIntToScalar(x), SkIntToScalar(y));
567 StitchData stitchData;
568 for (int i = 0; i < count; ++i) {
569 result[i] = shade(point, stitchData);
570 point.fX += SK_Scalar1;
571 }
572 }
573
574 /////////////////////////////////////////////////////////////////////
575
576 #if defined(SK_GANESH)
577
578 class GrPerlinNoise2Effect : public GrFragmentProcessor {
579 public:
Make(SkPerlinNoiseShaderImpl::Type type,int numOctaves,bool stitchTiles,std::unique_ptr<SkPerlinNoiseShaderImpl::PaintingData> paintingData,GrSurfaceProxyView permutationsView,GrSurfaceProxyView noiseView,const GrCaps & caps)580 static std::unique_ptr<GrFragmentProcessor> Make(
581 SkPerlinNoiseShaderImpl::Type type,
582 int numOctaves,
583 bool stitchTiles,
584 std::unique_ptr<SkPerlinNoiseShaderImpl::PaintingData> paintingData,
585 GrSurfaceProxyView permutationsView,
586 GrSurfaceProxyView noiseView,
587 const GrCaps& caps) {
588 static constexpr GrSamplerState kRepeatXSampler = {GrSamplerState::WrapMode::kRepeat,
589 GrSamplerState::WrapMode::kClamp,
590 GrSamplerState::Filter::kNearest};
591 auto permutationsFP =
592 GrTextureEffect::Make(std::move(permutationsView), kPremul_SkAlphaType,
593 SkMatrix::I(), kRepeatXSampler, caps);
594 auto noiseFP = GrTextureEffect::Make(std::move(noiseView), kPremul_SkAlphaType,
595 SkMatrix::I(), kRepeatXSampler, caps);
596
597 return std::unique_ptr<GrFragmentProcessor>(
598 new GrPerlinNoise2Effect(type,
599 numOctaves,
600 stitchTiles,
601 std::move(paintingData),
602 std::move(permutationsFP),
603 std::move(noiseFP)));
604 }
605
name() const606 const char* name() const override { return "PerlinNoise"; }
607
clone() const608 std::unique_ptr<GrFragmentProcessor> clone() const override {
609 return std::unique_ptr<GrFragmentProcessor>(new GrPerlinNoise2Effect(*this));
610 }
611
stitchData() const612 const SkPerlinNoiseShaderImpl::StitchData& stitchData() const { return fPaintingData->fStitchDataInit; }
613
type() const614 SkPerlinNoiseShaderImpl::Type type() const { return fType; }
stitchTiles() const615 bool stitchTiles() const { return fStitchTiles; }
baseFrequency() const616 const SkVector& baseFrequency() const { return fPaintingData->fBaseFrequency; }
numOctaves() const617 int numOctaves() const { return fNumOctaves; }
618
619 private:
620 class Impl : public ProgramImpl {
621 public:
622 void emitCode(EmitArgs&) override;
623
624 private:
625 void onSetData(const GrGLSLProgramDataManager&, const GrFragmentProcessor&) override;
626
627 GrGLSLProgramDataManager::UniformHandle fStitchDataUni;
628 GrGLSLProgramDataManager::UniformHandle fBaseFrequencyUni;
629 };
630
onMakeProgramImpl() const631 std::unique_ptr<ProgramImpl> onMakeProgramImpl() const override {
632 return std::make_unique<Impl>();
633 }
634
635 void onAddToKey(const GrShaderCaps& caps, skgpu::KeyBuilder* b) const override;
636
onIsEqual(const GrFragmentProcessor & sBase) const637 bool onIsEqual(const GrFragmentProcessor& sBase) const override {
638 const GrPerlinNoise2Effect& s = sBase.cast<GrPerlinNoise2Effect>();
639 return fType == s.fType &&
640 fPaintingData->fBaseFrequency == s.fPaintingData->fBaseFrequency &&
641 fNumOctaves == s.fNumOctaves &&
642 fStitchTiles == s.fStitchTiles &&
643 fPaintingData->fStitchDataInit == s.fPaintingData->fStitchDataInit;
644 }
645
GrPerlinNoise2Effect(SkPerlinNoiseShaderImpl::Type type,int numOctaves,bool stitchTiles,std::unique_ptr<SkPerlinNoiseShaderImpl::PaintingData> paintingData,std::unique_ptr<GrFragmentProcessor> permutationsFP,std::unique_ptr<GrFragmentProcessor> noiseFP)646 GrPerlinNoise2Effect(SkPerlinNoiseShaderImpl::Type type,
647 int numOctaves,
648 bool stitchTiles,
649 std::unique_ptr<SkPerlinNoiseShaderImpl::PaintingData> paintingData,
650 std::unique_ptr<GrFragmentProcessor> permutationsFP,
651 std::unique_ptr<GrFragmentProcessor> noiseFP)
652 : INHERITED(kGrPerlinNoise2Effect_ClassID, kNone_OptimizationFlags)
653 , fType(type)
654 , fNumOctaves(numOctaves)
655 , fStitchTiles(stitchTiles)
656 , fPaintingData(std::move(paintingData)) {
657 this->registerChild(std::move(permutationsFP), SkSL::SampleUsage::Explicit());
658 this->registerChild(std::move(noiseFP), SkSL::SampleUsage::Explicit());
659 this->setUsesSampleCoordsDirectly();
660 }
661
GrPerlinNoise2Effect(const GrPerlinNoise2Effect & that)662 GrPerlinNoise2Effect(const GrPerlinNoise2Effect& that)
663 : INHERITED(that)
664 , fType(that.fType)
665 , fNumOctaves(that.fNumOctaves)
666 , fStitchTiles(that.fStitchTiles)
667 , fPaintingData(new SkPerlinNoiseShaderImpl::PaintingData(*that.fPaintingData)) {}
668
669 GR_DECLARE_FRAGMENT_PROCESSOR_TEST
670
671 SkPerlinNoiseShaderImpl::Type fType;
672 int fNumOctaves;
673 bool fStitchTiles;
674
675 std::unique_ptr<SkPerlinNoiseShaderImpl::PaintingData> fPaintingData;
676
677 using INHERITED = GrFragmentProcessor;
678 };
679
680 /////////////////////////////////////////////////////////////////////
GR_DEFINE_FRAGMENT_PROCESSOR_TEST(GrPerlinNoise2Effect)681 GR_DEFINE_FRAGMENT_PROCESSOR_TEST(GrPerlinNoise2Effect)
682
683 #if GR_TEST_UTILS
684 std::unique_ptr<GrFragmentProcessor> GrPerlinNoise2Effect::TestCreate(GrProcessorTestData* d) {
685 int numOctaves = d->fRandom->nextRangeU(2, 10);
686 bool stitchTiles = d->fRandom->nextBool();
687 SkScalar seed = SkIntToScalar(d->fRandom->nextU());
688 SkISize tileSize;
689 tileSize.fWidth = d->fRandom->nextRangeU(4, 4096);
690 tileSize.fHeight = d->fRandom->nextRangeU(4, 4096);
691 SkScalar baseFrequencyX = d->fRandom->nextRangeScalar(0.01f, 0.99f);
692 SkScalar baseFrequencyY = d->fRandom->nextRangeScalar(0.01f, 0.99f);
693
694 sk_sp<SkShader> shader(d->fRandom->nextBool() ?
695 SkPerlinNoiseShader::MakeFractalNoise(baseFrequencyX, baseFrequencyY, numOctaves, seed,
696 stitchTiles ? &tileSize : nullptr) :
697 SkPerlinNoiseShader::MakeTurbulence(baseFrequencyX, baseFrequencyY, numOctaves, seed,
698 stitchTiles ? &tileSize : nullptr));
699
700 GrTest::TestAsFPArgs asFPArgs(d);
701 return as_SB(shader)->asRootFragmentProcessor(asFPArgs.args(), GrTest::TestMatrix(d->fRandom));
702 }
703 #endif
704
emitCode(EmitArgs & args)705 void GrPerlinNoise2Effect::Impl::emitCode(EmitArgs& args) {
706 const GrPerlinNoise2Effect& pne = args.fFp.cast<GrPerlinNoise2Effect>();
707
708 GrGLSLFPFragmentBuilder* fragBuilder = args.fFragBuilder;
709 GrGLSLUniformHandler* uniformHandler = args.fUniformHandler;
710
711 fBaseFrequencyUni = uniformHandler->addUniform(&pne, kFragment_GrShaderFlag, SkSLType::kHalf2,
712 "baseFrequency");
713 const char* baseFrequencyUni = uniformHandler->getUniformCStr(fBaseFrequencyUni);
714
715 const char* stitchDataUni = nullptr;
716 if (pne.stitchTiles()) {
717 fStitchDataUni = uniformHandler->addUniform(&pne, kFragment_GrShaderFlag, SkSLType::kHalf2,
718 "stitchData");
719 stitchDataUni = uniformHandler->getUniformCStr(fStitchDataUni);
720 }
721
722 // Add noise function
723 const GrShaderVar gPerlinNoiseArgs[] = {{"chanCoord", SkSLType::kHalf },
724 {"noiseVec ", SkSLType::kHalf2}};
725
726 const GrShaderVar gPerlinNoiseStitchArgs[] = {{"chanCoord" , SkSLType::kHalf },
727 {"noiseVec" , SkSLType::kHalf2},
728 {"stitchData", SkSLType::kHalf2}};
729
730 SkString noiseCode;
731
732 noiseCode.append(
733 "half4 floorVal;"
734 "floorVal.xy = floor(noiseVec);"
735 "floorVal.zw = floorVal.xy + half2(1);"
736 "half2 fractVal = fract(noiseVec);"
737 // smooth curve : t^2*(3 - 2*t)
738 "half2 noiseSmooth = fractVal*fractVal*(half2(3) - 2*fractVal);"
739 );
740
741 // Adjust frequencies if we're stitching tiles
742 if (pne.stitchTiles()) {
743 noiseCode.append(
744 "if (floorVal.x >= stitchData.x) { floorVal.x -= stitchData.x; };"
745 "if (floorVal.y >= stitchData.y) { floorVal.y -= stitchData.y; };"
746 "if (floorVal.z >= stitchData.x) { floorVal.z -= stitchData.x; };"
747 "if (floorVal.w >= stitchData.y) { floorVal.w -= stitchData.y; };"
748 );
749 }
750
751 // NOTE: We need to explicitly pass half4(1) as input color here, because the helper function
752 // can't see fInputColor (which is "_input" in the FP's outer function). skbug.com/10506
753 SkString sampleX = this->invokeChild(0, "half4(1)", args, "half2(floorVal.x, 0.5)");
754 SkString sampleY = this->invokeChild(0, "half4(1)", args, "half2(floorVal.z, 0.5)");
755 noiseCode.appendf("half2 latticeIdx = half2(%s.a, %s.a);", sampleX.c_str(), sampleY.c_str());
756
757 #if defined(SK_BUILD_FOR_ANDROID)
758 // Android rounding for Tegra devices, like, for example: Xoom (Tegra 2), Nexus 7 (Tegra 3).
759 // The issue is that colors aren't accurate enough on Tegra devices. For example, if an 8 bit
760 // value of 124 (or 0.486275 here) is entered, we can get a texture value of 123.513725
761 // (or 0.484368 here). The following rounding operation prevents these precision issues from
762 // affecting the result of the noise by making sure that we only have multiples of 1/255.
763 // (Note that 1/255 is about 0.003921569, which is the value used here).
764 noiseCode.append(
765 "latticeIdx = floor(latticeIdx * half2(255.0) + half2(0.5)) * half2(0.003921569);");
766 #endif
767
768 // Get (x,y) coordinates with the permutated x
769 noiseCode.append("half4 bcoords = 256*latticeIdx.xyxy + floorVal.yyww;");
770
771 noiseCode.append("half2 uv;");
772
773 // This is the math to convert the two 16bit integer packed into rgba 8 bit input into a
774 // [-1,1] vector and perform a dot product between that vector and the provided vector.
775 // Save it as a string because we will repeat it 4x.
776 static constexpr const char* inc8bit = "0.00390625"; // 1.0 / 256.0
777 SkString dotLattice =
778 SkStringPrintf("dot((lattice.ga + lattice.rb*%s)*2 - half2(1), fractVal)", inc8bit);
779
780 SkString sampleA = this->invokeChild(1, "half4(1)", args, "half2(bcoords.x, chanCoord)");
781 SkString sampleB = this->invokeChild(1, "half4(1)", args, "half2(bcoords.y, chanCoord)");
782 SkString sampleC = this->invokeChild(1, "half4(1)", args, "half2(bcoords.w, chanCoord)");
783 SkString sampleD = this->invokeChild(1, "half4(1)", args, "half2(bcoords.z, chanCoord)");
784
785 // Compute u, at offset (0,0)
786 noiseCode.appendf("half4 lattice = %s;", sampleA.c_str());
787 noiseCode.appendf("uv.x = %s;", dotLattice.c_str());
788
789 // Compute v, at offset (-1,0)
790 noiseCode.append("fractVal.x -= 1.0;");
791 noiseCode.appendf("lattice = %s;", sampleB.c_str());
792 noiseCode.appendf("uv.y = %s;", dotLattice.c_str());
793
794 // Compute 'a' as a linear interpolation of 'u' and 'v'
795 noiseCode.append("half2 ab;");
796 noiseCode.append("ab.x = mix(uv.x, uv.y, noiseSmooth.x);");
797
798 // Compute v, at offset (-1,-1)
799 noiseCode.append("fractVal.y -= 1.0;");
800 noiseCode.appendf("lattice = %s;", sampleC.c_str());
801 noiseCode.appendf("uv.y = %s;", dotLattice.c_str());
802
803 // Compute u, at offset (0,-1)
804 noiseCode.append("fractVal.x += 1.0;");
805 noiseCode.appendf("lattice = %s;", sampleD.c_str());
806 noiseCode.appendf("uv.x = %s;", dotLattice.c_str());
807
808 // Compute 'b' as a linear interpolation of 'u' and 'v'
809 noiseCode.append("ab.y = mix(uv.x, uv.y, noiseSmooth.x);");
810 // Compute the noise as a linear interpolation of 'a' and 'b'
811 noiseCode.append("return mix(ab.x, ab.y, noiseSmooth.y);");
812
813 SkString noiseFuncName = fragBuilder->getMangledFunctionName("noiseFuncName");
814 if (pne.stitchTiles()) {
815 fragBuilder->emitFunction(SkSLType::kHalf, noiseFuncName.c_str(),
816 {gPerlinNoiseStitchArgs, std::size(gPerlinNoiseStitchArgs)},
817 noiseCode.c_str());
818 } else {
819 fragBuilder->emitFunction(SkSLType::kHalf, noiseFuncName.c_str(),
820 {gPerlinNoiseArgs, std::size(gPerlinNoiseArgs)},
821 noiseCode.c_str());
822 }
823
824 // There are rounding errors if the floor operation is not performed here
825 fragBuilder->codeAppendf("half2 noiseVec = half2(floor(%s.xy) * %s);",
826 args.fSampleCoord, baseFrequencyUni);
827
828 // Clear the color accumulator
829 fragBuilder->codeAppendf("half4 color = half4(0);");
830
831 if (pne.stitchTiles()) {
832 // Set up TurbulenceInitial stitch values.
833 fragBuilder->codeAppendf("half2 stitchData = %s;", stitchDataUni);
834 }
835
836 fragBuilder->codeAppendf("half ratio = 1.0;");
837
838 // Loop over all octaves
839 fragBuilder->codeAppendf("for (int octave = 0; octave < %d; ++octave) {", pne.numOctaves());
840 fragBuilder->codeAppendf( "color += ");
841 if (pne.type() != SkPerlinNoiseShaderImpl::kFractalNoise_Type) {
842 fragBuilder->codeAppend("abs(");
843 }
844
845 // There are 4 lines, put y coords at center of each.
846 static constexpr const char* chanCoordR = "0.5";
847 static constexpr const char* chanCoordG = "1.5";
848 static constexpr const char* chanCoordB = "2.5";
849 static constexpr const char* chanCoordA = "3.5";
850 if (pne.stitchTiles()) {
851 fragBuilder->codeAppendf(
852 "half4(%s(%s, noiseVec, stitchData), %s(%s, noiseVec, stitchData),"
853 "%s(%s, noiseVec, stitchData), %s(%s, noiseVec, stitchData))",
854 noiseFuncName.c_str(), chanCoordR,
855 noiseFuncName.c_str(), chanCoordG,
856 noiseFuncName.c_str(), chanCoordB,
857 noiseFuncName.c_str(), chanCoordA);
858 } else {
859 fragBuilder->codeAppendf(
860 "half4(%s(%s, noiseVec), %s(%s, noiseVec),"
861 "%s(%s, noiseVec), %s(%s, noiseVec))",
862 noiseFuncName.c_str(), chanCoordR,
863 noiseFuncName.c_str(), chanCoordG,
864 noiseFuncName.c_str(), chanCoordB,
865 noiseFuncName.c_str(), chanCoordA);
866 }
867 if (pne.type() != SkPerlinNoiseShaderImpl::kFractalNoise_Type) {
868 fragBuilder->codeAppend(")"); // end of "abs("
869 }
870 fragBuilder->codeAppend(" * ratio;");
871
872 fragBuilder->codeAppend("noiseVec *= half2(2.0);"
873 "ratio *= 0.5;");
874
875 if (pne.stitchTiles()) {
876 fragBuilder->codeAppend("stitchData *= half2(2.0);");
877 }
878 fragBuilder->codeAppend("}"); // end of the for loop on octaves
879
880 if (pne.type() == SkPerlinNoiseShaderImpl::kFractalNoise_Type) {
881 // The value of turbulenceFunctionResult comes from ((turbulenceFunctionResult) + 1) / 2
882 // by fractalNoise and (turbulenceFunctionResult) by turbulence.
883 fragBuilder->codeAppendf("color = color * half4(0.5) + half4(0.5);");
884 }
885
886 // Clamp values
887 fragBuilder->codeAppendf("color = saturate(color);");
888
889 // Pre-multiply the result
890 fragBuilder->codeAppendf("return half4(color.rgb * color.aaa, color.a);");
891 }
892
onSetData(const GrGLSLProgramDataManager & pdman,const GrFragmentProcessor & processor)893 void GrPerlinNoise2Effect::Impl::onSetData(const GrGLSLProgramDataManager& pdman,
894 const GrFragmentProcessor& processor) {
895 const GrPerlinNoise2Effect& turbulence = processor.cast<GrPerlinNoise2Effect>();
896
897 const SkVector& baseFrequency = turbulence.baseFrequency();
898 pdman.set2f(fBaseFrequencyUni, baseFrequency.fX, baseFrequency.fY);
899
900 if (turbulence.stitchTiles()) {
901 const SkPerlinNoiseShaderImpl::StitchData& stitchData = turbulence.stitchData();
902 pdman.set2f(fStitchDataUni,
903 SkIntToScalar(stitchData.fWidth),
904 SkIntToScalar(stitchData.fHeight));
905 }
906 }
907
onAddToKey(const GrShaderCaps & caps,skgpu::KeyBuilder * b) const908 void GrPerlinNoise2Effect::onAddToKey(const GrShaderCaps& caps, skgpu::KeyBuilder* b) const {
909 uint32_t key = fNumOctaves;
910 key = key << 3; // Make room for next 3 bits
911 switch (fType) {
912 case SkPerlinNoiseShaderImpl::kFractalNoise_Type:
913 key |= 0x1;
914 break;
915 case SkPerlinNoiseShaderImpl::kTurbulence_Type:
916 key |= 0x2;
917 break;
918 default:
919 // leave key at 0
920 break;
921 }
922 if (fStitchTiles) {
923 key |= 0x4; // Flip the 3rd bit if tile stitching is on
924 }
925 b->add32(key);
926 }
927
928 /////////////////////////////////////////////////////////////////////
929
asFragmentProcessor(const GrFPArgs & args,const MatrixRec & mRec) const930 std::unique_ptr<GrFragmentProcessor> SkPerlinNoiseShaderImpl::asFragmentProcessor(
931 const GrFPArgs& args, const MatrixRec& mRec) const {
932 SkASSERT(args.fContext);
933
934 const SkMatrix& totalMatrix = mRec.totalMatrix();
935
936 // Either we don't stitch tiles, either we have a valid tile size
937 SkASSERT(!fStitchTiles || !fTileSize.isEmpty());
938
939 auto paintingData = std::make_unique<SkPerlinNoiseShaderImpl::PaintingData>(fTileSize,
940 fSeed,
941 fBaseFrequencyX,
942 fBaseFrequencyY,
943 totalMatrix);
944
945 // Like shadeSpan, we start from device space. We will account for that below with a device
946 // space effect.
947
948 auto context = args.fContext;
949
950 if (0 == fNumOctaves) {
951 if (kFractalNoise_Type == fType) {
952 // Incoming alpha is assumed to be 1. So emit rgba = (1/4, 1/4, 1/4, 1/2)
953 // TODO: Either treat the output of this shader as sRGB or allow client to specify a
954 // color space of the noise. Either way, this case (and the GLSL) need to convert to
955 // the destination.
956 return GrFragmentProcessor::MakeColor(SkPMColor4f::FromBytes_RGBA(0x80404040));
957 }
958 // Emit zero.
959 return GrFragmentProcessor::MakeColor(SK_PMColor4fTRANSPARENT);
960 }
961
962 const SkBitmap& permutationsBitmap = paintingData->getPermutationsBitmap();
963 const SkBitmap& noiseBitmap = paintingData->getNoiseBitmap();
964
965 auto permutationsView = std::get<0>(GrMakeCachedBitmapProxyView(
966 context,
967 permutationsBitmap,
968 /*label=*/"PerlinNoiseShader_FragmentProcessor_PermutationsView"));
969 auto noiseView = std::get<0>(GrMakeCachedBitmapProxyView(
970 context, noiseBitmap, /*label=*/"PerlinNoiseShader_FragmentProcessor_NoiseView"));
971
972 if (permutationsView && noiseView) {
973 return GrFragmentProcessor::DeviceSpace(
974 GrMatrixEffect::Make(SkMatrix::Translate(1 - totalMatrix.getTranslateX(),
975 1 - totalMatrix.getTranslateY()),
976 GrPerlinNoise2Effect::Make(fType,
977 fNumOctaves,
978 fStitchTiles,
979 std::move(paintingData),
980 std::move(permutationsView),
981 std::move(noiseView),
982 *context->priv().caps())));
983 }
984 return nullptr;
985 }
986
987 #endif
988
989 ///////////////////////////////////////////////////////////////////////////////////////////////////
990
valid_input(SkScalar baseX,SkScalar baseY,int numOctaves,const SkISize * tileSize,SkScalar seed)991 static bool valid_input(SkScalar baseX, SkScalar baseY, int numOctaves, const SkISize* tileSize,
992 SkScalar seed) {
993 if (!(baseX >= 0 && baseY >= 0)) {
994 return false;
995 }
996 if (!(numOctaves >= 0 && numOctaves <= SkPerlinNoiseShaderImpl::kMaxOctaves)) {
997 return false;
998 }
999 if (tileSize && !(tileSize->width() >= 0 && tileSize->height() >= 0)) {
1000 return false;
1001 }
1002 if (!SkScalarIsFinite(seed)) {
1003 return false;
1004 }
1005 return true;
1006 }
1007
MakeFractalNoise(SkScalar baseFrequencyX,SkScalar baseFrequencyY,int numOctaves,SkScalar seed,const SkISize * tileSize)1008 sk_sp<SkShader> SkPerlinNoiseShader::MakeFractalNoise(SkScalar baseFrequencyX,
1009 SkScalar baseFrequencyY,
1010 int numOctaves, SkScalar seed,
1011 const SkISize* tileSize) {
1012 if (!valid_input(baseFrequencyX, baseFrequencyY, numOctaves, tileSize, seed)) {
1013 return nullptr;
1014 }
1015 return sk_sp<SkShader>(new SkPerlinNoiseShaderImpl(SkPerlinNoiseShaderImpl::kFractalNoise_Type,
1016 baseFrequencyX, baseFrequencyY, numOctaves, seed,
1017 tileSize));
1018 }
1019
MakeTurbulence(SkScalar baseFrequencyX,SkScalar baseFrequencyY,int numOctaves,SkScalar seed,const SkISize * tileSize)1020 sk_sp<SkShader> SkPerlinNoiseShader::MakeTurbulence(SkScalar baseFrequencyX,
1021 SkScalar baseFrequencyY,
1022 int numOctaves, SkScalar seed,
1023 const SkISize* tileSize) {
1024 if (!valid_input(baseFrequencyX, baseFrequencyY, numOctaves, tileSize, seed)) {
1025 return nullptr;
1026 }
1027 return sk_sp<SkShader>(new SkPerlinNoiseShaderImpl(SkPerlinNoiseShaderImpl::kTurbulence_Type,
1028 baseFrequencyX, baseFrequencyY, numOctaves, seed,
1029 tileSize));
1030 }
1031
RegisterFlattenables()1032 void SkPerlinNoiseShader::RegisterFlattenables() {
1033 SK_REGISTER_FLATTENABLE(SkPerlinNoiseShaderImpl);
1034 }
1035