1/*
2 * Copyright 2014 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#include "src/gpu/effects/GrMatrixConvolutionEffect.h"
8
9#include "src/gpu/GrTexture.h"
10#include "src/gpu/GrTextureProxy.h"
11#include "src/gpu/glsl/GrGLSLFragmentProcessor.h"
12#include "src/gpu/glsl/GrGLSLFragmentShaderBuilder.h"
13#include "src/gpu/glsl/GrGLSLProgramDataManager.h"
14#include "src/gpu/glsl/GrGLSLUniformHandler.h"
15
16class GrGLMatrixConvolutionEffect : public GrGLSLFragmentProcessor {
17public:
18 void emitCode(EmitArgs&) override;
19
20 static inline void GenKey(const GrProcessor&, const GrShaderCaps&, GrProcessorKeyBuilder*);
21
22protected:
23 void onSetData(const GrGLSLProgramDataManager&, const GrFragmentProcessor&) override;
24
25private:
26 typedef GrGLSLProgramDataManager::UniformHandle UniformHandle;
27
28 UniformHandle fKernelUni;
29 UniformHandle fImageIncrementUni;
30 UniformHandle fKernelOffsetUni;
31 UniformHandle fGainUni;
32 UniformHandle fBiasUni;
33 GrTextureDomain::GLDomain fDomain;
34
35 typedef GrGLSLFragmentProcessor INHERITED;
36};
37
38void GrGLMatrixConvolutionEffect::emitCode(EmitArgs& args) {
39 const GrMatrixConvolutionEffect& mce = args.fFp.cast<GrMatrixConvolutionEffect>();
40 const GrTextureDomain& domain = mce.domain();
41
42 int kWidth = mce.kernelSize().width();
43 int kHeight = mce.kernelSize().height();
44
45 int arrayCount = (kWidth * kHeight + 3) / 4;
46 SkASSERT(4 * arrayCount >= kWidth * kHeight);
47
48 GrGLSLUniformHandler* uniformHandler = args.fUniformHandler;
49 fImageIncrementUni = uniformHandler->addUniform(&mce, kFragment_GrShaderFlag, kHalf2_GrSLType,
50 "ImageIncrement");
51 fKernelUni = uniformHandler->addUniformArray(&mce, kFragment_GrShaderFlag, kHalf4_GrSLType,
52 "Kernel",
53 arrayCount);
54 fKernelOffsetUni = uniformHandler->addUniform(&mce, kFragment_GrShaderFlag, kHalf2_GrSLType,
55 "KernelOffset");
56 fGainUni = uniformHandler->addUniform(&mce, kFragment_GrShaderFlag, kHalf_GrSLType, "Gain");
57 fBiasUni = uniformHandler->addUniform(&mce, kFragment_GrShaderFlag, kHalf_GrSLType, "Bias");
58
59 const char* kernelOffset = uniformHandler->getUniformCStr(fKernelOffsetUni);
60 const char* imgInc = uniformHandler->getUniformCStr(fImageIncrementUni);
61 const char* kernel = uniformHandler->getUniformCStr(fKernelUni);
62 const char* gain = uniformHandler->getUniformCStr(fGainUni);
63 const char* bias = uniformHandler->getUniformCStr(fBiasUni);
64
65 GrGLSLFPFragmentBuilder* fragBuilder = args.fFragBuilder;
66 SkString coords2D = fragBuilder->ensureCoords2D(args.fTransformedCoords[0].fVaryingPoint);
67 fragBuilder->codeAppend("half4 sum = half4(0, 0, 0, 0);");
68 fragBuilder->codeAppendf("float2 coord = %s - %s * %s;", coords2D.c_str(), kernelOffset, imgInc);
69 fragBuilder->codeAppend("half4 c;");
70
71 const char* kVecSuffix[4] = { ".x", ".y", ".z", ".w" };
72 for (int y = 0; y < kHeight; y++) {
73 for (int x = 0; x < kWidth; x++) {
74 GrGLSLShaderBuilder::ShaderBlock block(fragBuilder);
75 int offset = y*kWidth + x;
76
77 fragBuilder->codeAppendf("half k = %s[%d]%s;", kernel, offset / 4,
78 kVecSuffix[offset & 0x3]);
79 SkString coord;
80 coord.printf("coord + half2(%d, %d) * %s", x, y, imgInc);
81 fDomain.sampleTexture(&mce,
82 fragBuilder,
83 uniformHandler,
84 args.fShaderCaps,
85 domain,
86 "c",
87 coord,
88 args.fTexSamplers[0]);
89 if (!mce.convolveAlpha()) {
90 fragBuilder->codeAppend("c.rgb /= c.a;");
91 fragBuilder->codeAppend("c.rgb = saturate(c.rgb);");
92 }
93 fragBuilder->codeAppend("sum += c * k;");
94 }
95 }
96 if (mce.convolveAlpha()) {
97 fragBuilder->codeAppendf("%s = sum * %s + %s;", args.fOutputColor, gain, bias);
98 fragBuilder->codeAppendf("%s.a = saturate(%s.a);", args.fOutputColor, args.fOutputColor);
99 fragBuilder->codeAppendf("%s.rgb = clamp(%s.rgb, 0.0, %s.a);",
100 args.fOutputColor, args.fOutputColor, args.fOutputColor);
101 } else {
102 fDomain.sampleTexture(&mce,
103 fragBuilder,
104 uniformHandler,
105 args.fShaderCaps,
106 domain,
107 "c",
108 coords2D,
109 args.fTexSamplers[0]);
110 fragBuilder->codeAppendf("%s.a = c.a;", args.fOutputColor);
111 fragBuilder->codeAppendf("%s.rgb = saturate(sum.rgb * %s + %s);", args.fOutputColor, gain, bias);
112 fragBuilder->codeAppendf("%s.rgb *= %s.a;", args.fOutputColor, args.fOutputColor);
113 }
114 fragBuilder->codeAppendf("%s *= %s;\n", args.fOutputColor, args.fInputColor);
115}
116
117void GrGLMatrixConvolutionEffect::GenKey(const GrProcessor& processor,
118 const GrShaderCaps&, GrProcessorKeyBuilder* b) {
119 const GrMatrixConvolutionEffect& m = processor.cast<GrMatrixConvolutionEffect>();
120 SkASSERT(m.kernelSize().width() <= 0x7FFF && m.kernelSize().height() <= 0xFFFF);
121 uint32_t key = m.kernelSize().width() << 16 | m.kernelSize().height();
122 key |= m.convolveAlpha() ? 1U << 31 : 0;
123 b->add32(key);
124 b->add32(GrTextureDomain::GLDomain::DomainKey(m.domain()));
125}
126
127void GrGLMatrixConvolutionEffect::onSetData(const GrGLSLProgramDataManager& pdman,
128 const GrFragmentProcessor& processor) {
129 const GrMatrixConvolutionEffect& conv = processor.cast<GrMatrixConvolutionEffect>();
130 const auto& view = conv.textureSampler(0).view();
131 SkISize textureDims = view.proxy()->backingStoreDimensions();
132
133 float imageIncrement[2];
134 float ySign = view.origin() == kTopLeft_GrSurfaceOrigin ? 1.0f : -1.0f;
135 imageIncrement[0] = 1.0f / textureDims.width();
136 imageIncrement[1] = ySign / textureDims.height();
137 pdman.set2fv(fImageIncrementUni, 1, imageIncrement);
138 pdman.set2fv(fKernelOffsetUni, 1, conv.kernelOffset());
139 int kernelCount = conv.kernelSize().width() * conv.kernelSize().height();
140 int arrayCount = (kernelCount + 3) / 4;
141 SkASSERT(4 * arrayCount >= kernelCount);
142 pdman.set4fv(fKernelUni, arrayCount, conv.kernel());
143 pdman.set1f(fGainUni, conv.gain());
144 pdman.set1f(fBiasUni, conv.bias());
145 fDomain.setData(pdman, conv.domain(), view, conv.textureSampler(0).samplerState());
146}
147
148GrMatrixConvolutionEffect::GrMatrixConvolutionEffect(GrSurfaceProxyView srcView,
149 const SkIRect& srcBounds,
150 const SkISize& kernelSize,
151 const SkScalar* kernel,
152 SkScalar gain,
153 SkScalar bias,
154 const SkIPoint& kernelOffset,
155 GrTextureDomain::Mode tileMode,
156 bool convolveAlpha)
157 // To advertise either the modulation or opaqueness optimizations we'd have to examine the
158 // parameters.
159 : INHERITED(kGrMatrixConvolutionEffect_ClassID, kNone_OptimizationFlags)
160 , fCoordTransform(srcView.proxy(), srcView.origin())
161 , fDomain(srcView.proxy(), GrTextureDomain::MakeTexelDomain(srcBounds, tileMode),
162 tileMode, tileMode)
163 , fTextureSampler(std::move(srcView))
164 , fKernelSize(kernelSize)
165 , fGain(SkScalarToFloat(gain))
166 , fBias(SkScalarToFloat(bias) / 255.0f)
167 , fConvolveAlpha(convolveAlpha) {
168 this->addCoordTransform(&fCoordTransform);
169 this->setTextureSamplerCnt(1);
170 for (int i = 0; i < kernelSize.width() * kernelSize.height(); i++) {
171 fKernel[i] = SkScalarToFloat(kernel[i]);
172 }
173 fKernelOffset[0] = static_cast<float>(kernelOffset.x());
174 fKernelOffset[1] = static_cast<float>(kernelOffset.y());
175}
176
177GrMatrixConvolutionEffect::GrMatrixConvolutionEffect(const GrMatrixConvolutionEffect& that)
178 : INHERITED(kGrMatrixConvolutionEffect_ClassID, kNone_OptimizationFlags)
179 , fCoordTransform(that.fCoordTransform)
180 , fDomain(that.fDomain)
181 , fTextureSampler(that.fTextureSampler)
182 , fKernelSize(that.fKernelSize)
183 , fGain(that.fGain)
184 , fBias(that.fBias)
185 , fConvolveAlpha(that.fConvolveAlpha) {
186 this->addCoordTransform(&fCoordTransform);
187 this->setTextureSamplerCnt(1);
188 memcpy(fKernel, that.fKernel, sizeof(float) * fKernelSize.width() * fKernelSize.height());
189 memcpy(fKernelOffset, that.fKernelOffset, sizeof(fKernelOffset));
190}
191
192std::unique_ptr<GrFragmentProcessor> GrMatrixConvolutionEffect::clone() const {
193 return std::unique_ptr<GrFragmentProcessor>(new GrMatrixConvolutionEffect(*this));
194}
195
196void GrMatrixConvolutionEffect::onGetGLSLProcessorKey(const GrShaderCaps& caps,
197 GrProcessorKeyBuilder* b) const {
198 GrGLMatrixConvolutionEffect::GenKey(*this, caps, b);
199}
200
201GrGLSLFragmentProcessor* GrMatrixConvolutionEffect::onCreateGLSLInstance() const {
202 return new GrGLMatrixConvolutionEffect;
203}
204
205bool GrMatrixConvolutionEffect::onIsEqual(const GrFragmentProcessor& sBase) const {
206 const GrMatrixConvolutionEffect& s = sBase.cast<GrMatrixConvolutionEffect>();
207 return fKernelSize == s.kernelSize() &&
208 !memcmp(fKernel, s.kernel(),
209 fKernelSize.width() * fKernelSize.height() * sizeof(float)) &&
210 fGain == s.gain() &&
211 fBias == s.bias() &&
212 !memcmp(fKernelOffset, s.kernelOffset(), sizeof(fKernelOffset)) &&
213 fConvolveAlpha == s.convolveAlpha() &&
214 fDomain == s.domain();
215}
216
217static void fill_in_1D_gaussian_kernel_with_stride(float* kernel, int size, int stride,
218 float twoSigmaSqrd) {
219 SkASSERT(!SkScalarNearlyZero(twoSigmaSqrd, SK_ScalarNearlyZero));
220
221 const float sigmaDenom = 1.0f / twoSigmaSqrd;
222 const int radius = size / 2;
223
224 float sum = 0.0f;
225 for (int i = 0; i < size; ++i) {
226 float term = static_cast<float>(i - radius);
227 // Note that the constant term (1/(sqrt(2*pi*sigma^2)) of the Gaussian
228 // is dropped here, since we renormalize the kernel below.
229 kernel[i * stride] = sk_float_exp(-term * term * sigmaDenom);
230 sum += kernel[i * stride];
231 }
232 // Normalize the kernel
233 float scale = 1.0f / sum;
234 for (int i = 0; i < size; ++i) {
235 kernel[i * stride] *= scale;
236 }
237}
238
239static void fill_in_2D_gaussian_kernel(float* kernel, int width, int height,
240 SkScalar sigmaX, SkScalar sigmaY) {
241 SkASSERT(width * height <= MAX_KERNEL_SIZE);
242 const float twoSigmaSqrdX = 2.0f * SkScalarToFloat(SkScalarSquare(sigmaX));
243 const float twoSigmaSqrdY = 2.0f * SkScalarToFloat(SkScalarSquare(sigmaY));
244
245 // TODO: in all of these degenerate cases we're uploading (and using) a whole lot of zeros.
246 if (SkScalarNearlyZero(twoSigmaSqrdX, SK_ScalarNearlyZero) ||
247 SkScalarNearlyZero(twoSigmaSqrdY, SK_ScalarNearlyZero)) {
248 // In this case the 2D Gaussian degenerates to a 1D Gaussian (in X or Y) or a point
249 SkASSERT(3 == width || 3 == height);
250 memset(kernel, 0, width*height*sizeof(float));
251
252 if (SkScalarNearlyZero(twoSigmaSqrdX, SK_ScalarNearlyZero) &&
253 SkScalarNearlyZero(twoSigmaSqrdY, SK_ScalarNearlyZero)) {
254 // A point
255 SkASSERT(3 == width && 3 == height);
256 kernel[4] = 1.0f;
257 } else if (SkScalarNearlyZero(twoSigmaSqrdX, SK_ScalarNearlyZero)) {
258 // A 1D Gaussian in Y
259 SkASSERT(3 == width);
260 // Down the middle column of the kernel with a stride of width
261 fill_in_1D_gaussian_kernel_with_stride(&kernel[1], height, width, twoSigmaSqrdY);
262 } else {
263 // A 1D Gaussian in X
264 SkASSERT(SkScalarNearlyZero(twoSigmaSqrdY, SK_ScalarNearlyZero));
265 SkASSERT(3 == height);
266 // Down the middle row of the kernel with a stride of 1
267 fill_in_1D_gaussian_kernel_with_stride(&kernel[width], width, 1, twoSigmaSqrdX);
268 }
269 return;
270 }
271
272 const float sigmaXDenom = 1.0f / twoSigmaSqrdX;
273 const float sigmaYDenom = 1.0f / twoSigmaSqrdY;
274 const int xRadius = width / 2;
275 const int yRadius = height / 2;
276
277 float sum = 0.0f;
278 for (int x = 0; x < width; x++) {
279 float xTerm = static_cast<float>(x - xRadius);
280 xTerm = xTerm * xTerm * sigmaXDenom;
281 for (int y = 0; y < height; y++) {
282 float yTerm = static_cast<float>(y - yRadius);
283 float xyTerm = sk_float_exp(-(xTerm + yTerm * yTerm * sigmaYDenom));
284 // Note that the constant term (1/(sqrt(2*pi*sigma^2)) of the Gaussian
285 // is dropped here, since we renormalize the kernel below.
286 kernel[y * width + x] = xyTerm;
287 sum += xyTerm;
288 }
289 }
290 // Normalize the kernel
291 float scale = 1.0f / sum;
292 for (int i = 0; i < width * height; ++i) {
293 kernel[i] *= scale;
294 }
295}
296
297// Static function to create a 2D convolution
298std::unique_ptr<GrFragmentProcessor> GrMatrixConvolutionEffect::MakeGaussian(
299 GrSurfaceProxyView srcView,
300 const SkIRect& srcBounds,
301 const SkISize& kernelSize,
302 SkScalar gain,
303 SkScalar bias,
304 const SkIPoint& kernelOffset,
305 GrTextureDomain::Mode tileMode,
306 bool convolveAlpha,
307 SkScalar sigmaX,
308 SkScalar sigmaY) {
309 // SkGpuBlurUtils is not as aggressive as it once was about avoiding texture domains.
310 // Check for a trivial case here where the domain can be avoided. TODO: Use GrTextureEffect
311 // here which includes this and more.
312 if (tileMode == GrTextureDomain::kClamp_Mode && !srcView.proxy()->isFullyLazy() &&
313 srcBounds.contains(SkIRect::MakeSize(srcView.proxy()->backingStoreDimensions()))) {
314 tileMode = GrTextureDomain::kIgnore_Mode;
315 }
316 float kernel[MAX_KERNEL_SIZE];
317
318 fill_in_2D_gaussian_kernel(kernel, kernelSize.width(), kernelSize.height(), sigmaX, sigmaY);
319
320 return std::unique_ptr<GrFragmentProcessor>(
321 new GrMatrixConvolutionEffect(std::move(srcView), srcBounds, kernelSize, kernel,
322 gain, bias, kernelOffset, tileMode, convolveAlpha));
323}
324
325GR_DEFINE_FRAGMENT_PROCESSOR_TEST(GrMatrixConvolutionEffect);
326
327#if GR_TEST_UTILS
328std::unique_ptr<GrFragmentProcessor> GrMatrixConvolutionEffect::TestCreate(GrProcessorTestData* d) {
329 auto [view, ct, at] = d->randomView();
330
331 int width = d->fRandom->nextRangeU(1, MAX_KERNEL_SIZE);
332 int height = d->fRandom->nextRangeU(1, MAX_KERNEL_SIZE / width);
333 SkISize kernelSize = SkISize::Make(width, height);
334 std::unique_ptr<SkScalar[]> kernel(new SkScalar[width * height]);
335 for (int i = 0; i < width * height; i++) {
336 kernel.get()[i] = d->fRandom->nextSScalar1();
337 }
338 SkScalar gain = d->fRandom->nextSScalar1();
339 SkScalar bias = d->fRandom->nextSScalar1();
340
341 uint32_t kernalOffsetX = d->fRandom->nextRangeU(0, kernelSize.width());
342 uint32_t kernalOffsetY = d->fRandom->nextRangeU(0, kernelSize.height());
343 SkIPoint kernelOffset = SkIPoint::Make(kernalOffsetX, kernalOffsetY);
344
345 uint32_t boundsX = d->fRandom->nextRangeU(0, view.width());
346 uint32_t boundsY = d->fRandom->nextRangeU(0, view.height());
347 uint32_t boundsW = d->fRandom->nextRangeU(0, view.width());
348 uint32_t boundsH = d->fRandom->nextRangeU(0, view.height());
349 SkIRect bounds = SkIRect::MakeXYWH(boundsX, boundsY, boundsW, boundsH);
350
351 GrTextureDomain::Mode tileMode =
352 static_cast<GrTextureDomain::Mode>(d->fRandom->nextRangeU(0, 2));
353 bool convolveAlpha = d->fRandom->nextBool();
354
355 return GrMatrixConvolutionEffect::Make(std::move(view),
356 bounds,
357 kernelSize,
358 kernel.get(),
359 gain,
360 bias,
361 kernelOffset,
362 tileMode,
363 convolveAlpha);
364}
365#endif
366