src/gpu/effects/GrConvolutionEffect.cpp

   1 /*
   2  * Copyright 2012 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 "GrConvolutionEffect.h"
   9 #include "glsl/GrGLSLFragmentProcessor.h"
  10 #include "glsl/GrGLSLFragmentShaderBuilder.h"
  11 #include "glsl/GrGLSLProgramBuilder.h"
  12 #include "glsl/GrGLSLProgramDataManager.h"
  13
  14 // For brevity
  15 typedef GrGLSLProgramDataManager::UniformHandle UniformHandle;
  16
  17 class GrGLConvolutionEffect : public GrGLSLFragmentProcessor {
  18 public:
  19     GrGLConvolutionEffect(const GrProcessor&);
  20
  21     virtual void emitCode(EmitArgs&) override;
  22
  23     static inline void GenKey(const GrProcessor&, const GrGLSLCaps&, GrProcessorKeyBuilder*);
  24
  25 protected:
  26     void onSetData(const GrGLSLProgramDataManager& pdman, const GrProcessor&) override;
  27
  28 private:
  29     int width() const { return Gr1DKernelEffect::WidthFromRadius(fRadius); }
  30     bool useBounds() const { return fUseBounds; }
  31     Gr1DKernelEffect::Direction direction() const { return fDirection; }
  32
  33     int                 fRadius;
  34     bool                fUseBounds;
  35     Gr1DKernelEffect::Direction    fDirection;
  36     UniformHandle       fKernelUni;
  37     UniformHandle       fImageIncrementUni;
  38     UniformHandle       fBoundsUni;
  39
  40     typedef GrGLSLFragmentProcessor INHERITED;
  41 };
  42
  43 GrGLConvolutionEffect::GrGLConvolutionEffect(const GrProcessor& processor) {
  44     const GrConvolutionEffect& c = processor.cast<GrConvolutionEffect>();
  45     fRadius = c.radius();
  46     fUseBounds = c.useBounds();
  47     fDirection = c.direction();
  48 }
  49
  50 void GrGLConvolutionEffect::emitCode(EmitArgs& args) {
  51     fImageIncrementUni = args.fBuilder->addUniform(GrGLSLProgramBuilder::kFragment_Visibility,
  52                                              kVec2f_GrSLType, kDefault_GrSLPrecision,
  53                                              "ImageIncrement");
  54     if (this->useBounds()) {
  55         fBoundsUni = args.fBuilder->addUniform(GrGLSLProgramBuilder::kFragment_Visibility,
  56                                          kVec2f_GrSLType, kDefault_GrSLPrecision,
  57                                          "Bounds");
  58     }
  59     fKernelUni = args.fBuilder->addUniformArray(GrGLSLProgramBuilder::kFragment_Visibility,
  60                                           kFloat_GrSLType, kDefault_GrSLPrecision,
  61                                           "Kernel", this->width());
  62
  63     GrGLSLFragmentBuilder* fragBuilder = args.fFragBuilder;
  64     SkString coords2D = fragBuilder->ensureFSCoords2D(args.fCoords, 0);
  65
  66     fragBuilder->codeAppendf("\t\t%s = vec4(0, 0, 0, 0);\n", args.fOutputColor);
  67
  68     int width = this->width();
  69     const GrGLSLShaderVar& kernel = args.fBuilder->getUniformVariable(fKernelUni);
  70     const char* imgInc = args.fBuilder->getUniformCStr(fImageIncrementUni);
  71
  72     fragBuilder->codeAppendf("\t\tvec2 coord = %s - %d.0 * %s;\n", coords2D.c_str(), fRadius, imgInc);
  73
  74     // Manually unroll loop because some drivers don't; yields 20-30% speedup.
  75     for (int i = 0; i < width; i++) {
  76         SkString index;
  77         SkString kernelIndex;
  78         index.appendS32(i);
  79         kernel.appendArrayAccess(index.c_str(), &kernelIndex);
  80
  81         if (this->useBounds()) {
  82             // We used to compute a bool indicating whether we're in bounds or not, cast it to a
  83             // float, and then mul weight*texture_sample by the float. However, the Adreno 430 seems
  84             // to have a bug that caused corruption.
  85             const char* bounds = args.fBuilder->getUniformCStr(fBoundsUni);
  86             const char* component = this->direction() == Gr1DKernelEffect::kY_Direction ? "y" : "x";
  87             fragBuilder->codeAppendf("if (coord.%s >= %s.x && coord.%s <= %s.y) {",
  88                                      component, bounds, component, bounds);
  89         }
  90         fragBuilder->codeAppendf("\t\t%s += ", args.fOutputColor);
  91         fragBuilder->appendTextureLookup(args.fSamplers[0], "coord");
  92         fragBuilder->codeAppendf(" * %s;\n", kernelIndex.c_str());
  93         if (this->useBounds()) {
  94             fragBuilder->codeAppend("}");
  95         }
  96         fragBuilder->codeAppendf("\t\tcoord += %s;\n", imgInc);
  97     }
  98
  99     SkString modulate;
 100     GrGLSLMulVarBy4f(&modulate, args.fOutputColor, args.fInputColor);
 101     fragBuilder->codeAppend(modulate.c_str());
 102 }
 103
 104 void GrGLConvolutionEffect::onSetData(const GrGLSLProgramDataManager& pdman,
 105                                       const GrProcessor& processor) {
 106     const GrConvolutionEffect& conv = processor.cast<GrConvolutionEffect>();
 107     GrTexture& texture = *conv.texture(0);
 108     // the code we generated was for a specific kernel radius
 109     SkASSERT(conv.radius() == fRadius);
 110     float imageIncrement[2] = { 0 };
 111     float ySign = texture.origin() != kTopLeft_GrSurfaceOrigin ? 1.0f : -1.0f;
 112     switch (conv.direction()) {
 113         case Gr1DKernelEffect::kX_Direction:
 114             imageIncrement[0] = 1.0f / texture.width();
 115             break;
 116         case Gr1DKernelEffect::kY_Direction:
 117             imageIncrement[1] = ySign / texture.height();
 118             break;
 119         default:
 120             SkFAIL("Unknown filter direction.");
 121     }
 122     pdman.set2fv(fImageIncrementUni, 1, imageIncrement);
 123     if (conv.useBounds()) {
 124         const float* bounds = conv.bounds();
 125         if (Gr1DKernelEffect::kY_Direction == conv.direction() &&
 126             texture.origin() != kTopLeft_GrSurfaceOrigin) {
 127             pdman.set2f(fBoundsUni, 1.0f - bounds[1], 1.0f - bounds[0]);
 128         } else {
 129             pdman.set2f(fBoundsUni, bounds[0], bounds[1]);
 130         }
 131     }
 132     pdman.set1fv(fKernelUni, this->width(), conv.kernel());
 133 }
 134
 135 void GrGLConvolutionEffect::GenKey(const GrProcessor& processor, const GrGLSLCaps&,
 136                                    GrProcessorKeyBuilder* b) {
 137     const GrConvolutionEffect& conv = processor.cast<GrConvolutionEffect>();
 138     uint32_t key = conv.radius();
 139     key <<= 2;
 140     if (conv.useBounds()) {
 141         key |= 0x2;
 142         key |= GrConvolutionEffect::kY_Direction == conv.direction() ? 0x1 : 0x0;
 143     }
 144     b->add32(key);
 145 }
 146
 147 ///////////////////////////////////////////////////////////////////////////////
 148
 149 GrConvolutionEffect::GrConvolutionEffect(GrTexture* texture,
 150                                          Direction direction,
 151                                          int radius,
 152                                          const float* kernel,
 153                                          bool useBounds,
 154                                          float bounds[2])
 155     : INHERITED(texture, direction, radius), fUseBounds(useBounds) {
 156     this->initClassID<GrConvolutionEffect>();
 157     SkASSERT(radius <= kMaxKernelRadius);
 158     SkASSERT(kernel);
 159     int width = this->width();
 160     for (int i = 0; i < width; i++) {
 161         fKernel[i] = kernel[i];
 162     }
 163     memcpy(fBounds, bounds, sizeof(fBounds));
 164 }
 165
 166 GrConvolutionEffect::GrConvolutionEffect(GrTexture* texture,
 167                                          Direction direction,
 168                                          int radius,
 169                                          float gaussianSigma,
 170                                          bool useBounds,
 171                                          float bounds[2])
 172     : INHERITED(texture, direction, radius), fUseBounds(useBounds) {
 173     this->initClassID<GrConvolutionEffect>();
 174     SkASSERT(radius <= kMaxKernelRadius);
 175     int width = this->width();
 176
 177     float sum = 0.0f;
 178     float denom = 1.0f / (2.0f * gaussianSigma * gaussianSigma);
 179     for (int i = 0; i < width; ++i) {
 180         float x = static_cast<float>(i - this->radius());
 181         // Note that the constant term (1/(sqrt(2*pi*sigma^2)) of the Gaussian
 182         // is dropped here, since we renormalize the kernel below.
 183         fKernel[i] = sk_float_exp(- x * x * denom);
 184         sum += fKernel[i];
 185     }
 186     // Normalize the kernel
 187     float scale = 1.0f / sum;
 188     for (int i = 0; i < width; ++i) {
 189         fKernel[i] *= scale;
 190     }
 191     memcpy(fBounds, bounds, sizeof(fBounds));
 192 }
 193
 194 GrConvolutionEffect::~GrConvolutionEffect() {
 195 }
 196
 197 void GrConvolutionEffect::onGetGLSLProcessorKey(const GrGLSLCaps& caps,
 198                                                 GrProcessorKeyBuilder* b) const {
 199     GrGLConvolutionEffect::GenKey(*this, caps, b);
 200 }
 201
 202 GrGLSLFragmentProcessor* GrConvolutionEffect::onCreateGLSLInstance() const  {
 203     return new GrGLConvolutionEffect(*this);
 204 }
 205
 206 bool GrConvolutionEffect::onIsEqual(const GrFragmentProcessor& sBase) const {
 207     const GrConvolutionEffect& s = sBase.cast<GrConvolutionEffect>();
 208     return (this->radius() == s.radius() &&
 209             this->direction() == s.direction() &&
 210             this->useBounds() == s.useBounds() &&
 211             0 == memcmp(fBounds, s.fBounds, sizeof(fBounds)) &&
 212             0 == memcmp(fKernel, s.fKernel, this->width() * sizeof(float)));
 213 }
 214
 215 ///////////////////////////////////////////////////////////////////////////////
 216
 217 GR_DEFINE_FRAGMENT_PROCESSOR_TEST(GrConvolutionEffect);
 218
 219 const GrFragmentProcessor* GrConvolutionEffect::TestCreate(GrProcessorTestData* d) {
 220     int texIdx = d->fRandom->nextBool() ? GrProcessorUnitTest::kSkiaPMTextureIdx :
 221                                           GrProcessorUnitTest::kAlphaTextureIdx;
 222     Direction dir = d->fRandom->nextBool() ? kX_Direction : kY_Direction;
 223     int radius = d->fRandom->nextRangeU(1, kMaxKernelRadius);
 224     float kernel[kMaxKernelWidth];
 225     for (size_t i = 0; i < SK_ARRAY_COUNT(kernel); ++i) {
 226         kernel[i] = d->fRandom->nextSScalar1();
 227     }
 228     float bounds[2];
 229     for (size_t i = 0; i < SK_ARRAY_COUNT(bounds); ++i) {
 230         bounds[i] = d->fRandom->nextF();
 231     }
 232
 233     bool useBounds = d->fRandom->nextBool();
 234     return GrConvolutionEffect::Create(d->fTextures[texIdx],
 235                                        dir,
 236                                        radius,
 237                                        kernel,
 238                                        useBounds,
 239                                        bounds);
 240 }