src/effects/SkArithmeticMode_gpu.cpp

   1 /*
   2  * Copyright 2015 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 "SkArithmeticMode_gpu.h"
   9
  10 #if SK_SUPPORT_GPU
  11 #include "GrContext.h"
  12 #include "GrFragmentProcessor.h"
  13 #include "GrInvariantOutput.h"
  14 #include "GrProcessor.h"
  15 #include "GrTexture.h"
  16 #include "gl/GrGLCaps.h"
  17 #include "gl/GrGLProcessor.h"
  18 #include "gl/GrGLProgramDataManager.h"
  19 #include "gl/builders/GrGLProgramBuilder.h"
  20
  21 static const bool gUseUnpremul = false;
  22
  23 static void add_arithmetic_code(GrGLFPFragmentBuilder* fsBuilder,
  24                                 const char* inputColor,
  25                                 const char* dstColor,
  26                                 const char* outputColor,
  27                                 const char* kUni,
  28                                 bool enforcePMColor) {
  29     // We don't try to optimize for this case at all
  30     if (NULL == inputColor) {
  31         fsBuilder->codeAppend("const vec4 src = vec4(1);");
  32     } else {
  33         fsBuilder->codeAppendf("vec4 src = %s;", inputColor);
  34         if (gUseUnpremul) {
  35             fsBuilder->codeAppend("src.rgb = clamp(src.rgb / src.a, 0.0, 1.0);");
  36         }
  37     }
  38
  39     fsBuilder->codeAppendf("vec4 dst = %s;", dstColor);
  40     if (gUseUnpremul) {
  41         fsBuilder->codeAppend("dst.rgb = clamp(dst.rgb / dst.a, 0.0, 1.0);");
  42     }
  43
  44     fsBuilder->codeAppendf("%s = %s.x * src * dst + %s.y * src + %s.z * dst + %s.w;",
  45                            outputColor, kUni, kUni, kUni, kUni);
  46     fsBuilder->codeAppendf("%s = clamp(%s, 0.0, 1.0);\n", outputColor, outputColor);
  47     if (gUseUnpremul) {
  48         fsBuilder->codeAppendf("%s.rgb *= %s.a;", outputColor, outputColor);
  49     } else if (enforcePMColor) {
  50         fsBuilder->codeAppendf("%s.rgb = min(%s.rgb, %s.a);",
  51                                outputColor, outputColor, outputColor);
  52     }
  53 }
  54
  55 class GLArithmeticFP : public GrGLFragmentProcessor {
  56 public:
  57     GLArithmeticFP(const GrProcessor&)
  58         : fEnforcePMColor(true) {
  59     }
  60
  61     ~GLArithmeticFP() override {}
  62
  63     void emitCode(GrGLFPBuilder* builder,
  64                   const GrFragmentProcessor& fp,
  65                   const char* outputColor,
  66                   const char* inputColor,
  67                   const TransformedCoordsArray& coords,
  68                   const TextureSamplerArray& samplers) override {
  69         GrGLFPFragmentBuilder* fsBuilder = builder->getFragmentShaderBuilder();
  70         fsBuilder->codeAppend("vec4 bgColor = ");
  71         fsBuilder->appendTextureLookup(samplers[0], coords[0].c_str(), coords[0].getType());
  72         fsBuilder->codeAppendf(";");
  73         const char* dstColor = "bgColor";
  74
  75         fKUni = builder->addUniform(GrGLProgramBuilder::kFragment_Visibility,
  76                                     kVec4f_GrSLType, kDefault_GrSLPrecision,
  77                                     "k");
  78         const char* kUni = builder->getUniformCStr(fKUni);
  79
  80         add_arithmetic_code(fsBuilder, inputColor, dstColor, outputColor, kUni, fEnforcePMColor);
  81     }
  82
  83     void setData(const GrGLProgramDataManager& pdman, const GrProcessor& proc) override {
  84         const GrArithmeticFP& arith = proc.cast<GrArithmeticFP>();
  85         pdman.set4f(fKUni, arith.k1(), arith.k2(), arith.k3(), arith.k4());
  86         fEnforcePMColor = arith.enforcePMColor();
  87     }
  88
  89     static void GenKey(const GrProcessor& proc, const GrGLCaps& caps, GrProcessorKeyBuilder* b) {
  90         const GrArithmeticFP& arith = proc.cast<GrArithmeticFP>();
  91         uint32_t key = arith.enforcePMColor() ? 1 : 0;
  92         b->add32(key);
  93     }
  94
  95 private:
  96     GrGLProgramDataManager::UniformHandle fKUni;
  97     bool fEnforcePMColor;
  98
  99     typedef GrGLFragmentProcessor INHERITED;
 100 };
 101
 102 ///////////////////////////////////////////////////////////////////////////////
 103
 104 GrArithmeticFP::GrArithmeticFP(float k1, float k2, float k3, float k4,
 105                                bool enforcePMColor, GrTexture* background)
 106   : fK1(k1), fK2(k2), fK3(k3), fK4(k4), fEnforcePMColor(enforcePMColor) {
 107     this->initClassID<GrArithmeticFP>();
 108
 109     SkASSERT(background);
 110
 111     fBackgroundTransform.reset(kLocal_GrCoordSet, background,
 112                                GrTextureParams::kNone_FilterMode);
 113     this->addCoordTransform(&fBackgroundTransform);
 114     fBackgroundAccess.reset(background);
 115     this->addTextureAccess(&fBackgroundAccess);
 116 }
 117
 118 void GrArithmeticFP::getGLProcessorKey(const GrGLCaps& caps, GrProcessorKeyBuilder* b) const {
 119     GLArithmeticFP::GenKey(*this, caps, b);
 120 }
 121
 122 GrGLFragmentProcessor* GrArithmeticFP::createGLInstance() const {
 123     return SkNEW_ARGS(GLArithmeticFP, (*this));
 124 }
 125
 126 bool GrArithmeticFP::onIsEqual(const GrFragmentProcessor& fpBase) const {
 127     const GrArithmeticFP& fp = fpBase.cast<GrArithmeticFP>();
 128     return fK1 == fp.fK1 &&
 129            fK2 == fp.fK2 &&
 130            fK3 == fp.fK3 &&
 131            fK4 == fp.fK4 &&
 132            fEnforcePMColor == fp.fEnforcePMColor;
 133 }
 134
 135 void GrArithmeticFP::onComputeInvariantOutput(GrInvariantOutput* inout) const {
 136     // TODO: optimize this
 137     inout->setToUnknown(GrInvariantOutput::kWill_ReadInput);
 138 }
 139
 140 ///////////////////////////////////////////////////////////////////////////////
 141
 142 GrFragmentProcessor* GrArithmeticFP::TestCreate(SkRandom* rand,
 143                                                 GrContext*,
 144                                                 const GrDrawTargetCaps&,
 145                                                 GrTexture* textures[]) {
 146     float k1 = rand->nextF();
 147     float k2 = rand->nextF();
 148     float k3 = rand->nextF();
 149     float k4 = rand->nextF();
 150     bool enforcePMColor = rand->nextBool();
 151
 152     return SkNEW_ARGS(GrArithmeticFP, (k1, k2, k3, k4, enforcePMColor, textures[0]));
 153 }
 154
 155 GR_DEFINE_FRAGMENT_PROCESSOR_TEST(GrArithmeticFP);
 156
 157 ///////////////////////////////////////////////////////////////////////////////
 158 // Xfer Processor
 159 ///////////////////////////////////////////////////////////////////////////////
 160
 161 class ArithmeticXP : public GrXferProcessor {
 162 public:
 163     static GrXferProcessor* Create(float k1, float k2, float k3, float k4, bool enforcePMColor,
 164                                    const GrDeviceCoordTexture* dstCopy,
 165                                    bool willReadDstColor) {
 166         return SkNEW_ARGS(ArithmeticXP, (k1, k2, k3, k4, enforcePMColor, dstCopy,
 167                                          willReadDstColor));
 168     }
 169
 170     ~ArithmeticXP() override {};
 171
 172     const char* name() const override { return "Arithmetic"; }
 173
 174     GrGLXferProcessor* createGLInstance() const override;
 175
 176     bool hasSecondaryOutput() const override { return false; }
 177
 178     GrXferProcessor::OptFlags getOptimizations(const GrProcOptInfo& colorPOI,
 179                                                const GrProcOptInfo& coveragePOI,
 180                                                bool doesStencilWrite,
 181                                                GrColor* overrideColor,
 182                                                const GrDrawTargetCaps& caps) override;
 183
 184     void getBlendInfo(GrXferProcessor::BlendInfo* blendInfo) const override {
 185         blendInfo->fSrcBlend = kOne_GrBlendCoeff;
 186         blendInfo->fDstBlend = kZero_GrBlendCoeff;
 187         blendInfo->fBlendConstant = 0;
 188     }
 189
 190     float k1() const { return fK1; }
 191     float k2() const { return fK2; }
 192     float k3() const { return fK3; }
 193     float k4() const { return fK4; }
 194     bool enforcePMColor() const { return fEnforcePMColor; }
 195
 196 private:
 197     ArithmeticXP(float k1, float k2, float k3, float k4, bool enforcePMColor,
 198                    const GrDeviceCoordTexture* dstCopy, bool willReadDstColor);
 199
 200     void onGetGLProcessorKey(const GrGLCaps& caps, GrProcessorKeyBuilder* b) const override;
 201
 202     bool onIsEqual(const GrXferProcessor& xpBase) const override {
 203         const ArithmeticXP& xp = xpBase.cast<ArithmeticXP>();
 204         if (fK1 != xp.fK1 ||
 205             fK2 != xp.fK2 ||
 206             fK3 != xp.fK3 ||
 207             fK4 != xp.fK4 ||
 208             fEnforcePMColor != xp.fEnforcePMColor) {
 209             return false;
 210         }
 211         return true;
 212     }
 213
 214     float                       fK1, fK2, fK3, fK4;
 215     bool                        fEnforcePMColor;
 216
 217     typedef GrXferProcessor INHERITED;
 218 };
 219
 220 ///////////////////////////////////////////////////////////////////////////////
 221
 222 class GLArithmeticXP : public GrGLXferProcessor {
 223 public:
 224     GLArithmeticXP(const GrProcessor&)
 225         : fEnforcePMColor(true) {
 226     }
 227
 228     ~GLArithmeticXP() override {}
 229
 230     static void GenKey(const GrProcessor& processor, const GrGLCaps& caps,
 231                        GrProcessorKeyBuilder* b) {
 232         const ArithmeticXP& arith = processor.cast<ArithmeticXP>();
 233         uint32_t key = arith.enforcePMColor() ? 1 : 0;
 234         b->add32(key);
 235     }
 236
 237 private:
 238     void onEmitCode(const EmitArgs& args) override {
 239         GrGLFPFragmentBuilder* fsBuilder = args.fPB->getFragmentShaderBuilder();
 240
 241         const char* dstColor = fsBuilder->dstColor();
 242
 243         fKUni = args.fPB->addUniform(GrGLProgramBuilder::kFragment_Visibility,
 244                                      kVec4f_GrSLType, kDefault_GrSLPrecision,
 245                                      "k");
 246         const char* kUni = args.fPB->getUniformCStr(fKUni);
 247
 248         add_arithmetic_code(fsBuilder, args.fInputColor, dstColor, args.fOutputPrimary, kUni,
 249                             fEnforcePMColor);
 250
 251         fsBuilder->codeAppendf("%s = %s * %s + (vec4(1.0) - %s) * %s;",
 252                                args.fOutputPrimary, args.fOutputPrimary, args.fInputCoverage,
 253                                args.fInputCoverage, dstColor);
 254     }
 255
 256     void onSetData(const GrGLProgramDataManager& pdman,
 257                    const GrXferProcessor& processor) override {
 258         const ArithmeticXP& arith = processor.cast<ArithmeticXP>();
 259         pdman.set4f(fKUni, arith.k1(), arith.k2(), arith.k3(), arith.k4());
 260         fEnforcePMColor = arith.enforcePMColor();
 261     };
 262
 263     GrGLProgramDataManager::UniformHandle fKUni;
 264     bool fEnforcePMColor;
 265
 266     typedef GrGLXferProcessor INHERITED;
 267 };
 268
 269 ///////////////////////////////////////////////////////////////////////////////
 270
 271 ArithmeticXP::ArithmeticXP(float k1, float k2, float k3, float k4, bool enforcePMColor,
 272                            const GrDeviceCoordTexture* dstCopy, bool willReadDstColor)
 273     : INHERITED(dstCopy, willReadDstColor)
 274     , fK1(k1)
 275     , fK2(k2)
 276     , fK3(k3)
 277     , fK4(k4)
 278     , fEnforcePMColor(enforcePMColor) {
 279     this->initClassID<ArithmeticXP>();
 280 }
 281
 282 void ArithmeticXP::onGetGLProcessorKey(const GrGLCaps& caps, GrProcessorKeyBuilder* b) const {
 283     GLArithmeticXP::GenKey(*this, caps, b);
 284 }
 285
 286 GrGLXferProcessor* ArithmeticXP::createGLInstance() const {
 287     return SkNEW_ARGS(GLArithmeticXP, (*this));
 288 }
 289
 290 GrXferProcessor::OptFlags ArithmeticXP::getOptimizations(const GrProcOptInfo& colorPOI,
 291                                                          const GrProcOptInfo& coveragePOI,
 292                                                          bool doesStencilWrite,
 293                                                          GrColor* overrideColor,
 294                                                          const GrDrawTargetCaps& caps) {
 295    return GrXferProcessor::kNone_Opt;
 296 }
 297
 298 ///////////////////////////////////////////////////////////////////////////////
 299
 300 GrArithmeticXPFactory::GrArithmeticXPFactory(float k1, float k2, float k3, float k4,
 301                                              bool enforcePMColor)
 302     : fK1(k1), fK2(k2), fK3(k3), fK4(k4), fEnforcePMColor(enforcePMColor) {
 303     this->initClassID<GrArithmeticXPFactory>();
 304 }
 305
 306 GrXferProcessor*
 307 GrArithmeticXPFactory::onCreateXferProcessor(const GrDrawTargetCaps& caps,
 308                                              const GrProcOptInfo& colorPOI,
 309                                              const GrProcOptInfo& coveragePOI,
 310                                              const GrDeviceCoordTexture* dstCopy) const {
 311     return ArithmeticXP::Create(fK1, fK2, fK3, fK4, fEnforcePMColor, dstCopy,
 312                                 this->willReadDstColor(caps, colorPOI, coveragePOI));
 313 }
 314
 315
 316 void GrArithmeticXPFactory::getInvariantOutput(const GrProcOptInfo& colorPOI,
 317                                                const GrProcOptInfo& coveragePOI,
 318                                                GrXPFactory::InvariantOutput* output) const {
 319     output->fWillBlendWithDst = true;
 320
 321     // TODO: We could try to optimize this more. For example if we have solid coverage and fK1 and
 322     // fK3 are zero, then we won't be blending the color with dst at all so we can know what the
 323     // output color is (up to the valid color components passed in).
 324     output->fBlendedColorFlags = 0;
 325 }
 326
 327 GR_DEFINE_XP_FACTORY_TEST(GrArithmeticXPFactory);
 328
 329 GrXPFactory* GrArithmeticXPFactory::TestCreate(SkRandom* random,
 330                                                GrContext*,
 331                                                const GrDrawTargetCaps&,
 332                                                GrTexture*[]) {
 333     float k1 = random->nextF();
 334     float k2 = random->nextF();
 335     float k3 = random->nextF();
 336     float k4 = random->nextF();
 337     bool enforcePMColor = random->nextBool();
 338
 339     return GrArithmeticXPFactory::Create(k1, k2, k3, k4, enforcePMColor);
 340 }
 341
 342 #endif