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 "SkDisplacementMapEffect.h" 9 #include "SkFlattenableBuffers.h" 10 #include "SkUnPreMultiply.h" 11 #include "SkColorPriv.h" 12 #if SK_SUPPORT_GPU 13 #include "GrContext.h" 14 #include "gl/GrGLEffect.h" 15 #include "gl/GrGLEffectMatrix.h" 16 #include "GrTBackendEffectFactory.h" 17 #include "SkImageFilterUtils.h" 18 #endif 19 20 namespace { 21 22 template<SkDisplacementMapEffect::ChannelSelectorType type> 23 uint32_t getValue(SkColor, const SkUnPreMultiply::Scale*) { 24 SkASSERT(!"Unknown channel selector"); 25 return 0; 26 } 27 28 template<> uint32_t getValue<SkDisplacementMapEffect::kR_ChannelSelectorType>( 29 SkColor l, const SkUnPreMultiply::Scale* table) { 30 return SkUnPreMultiply::ApplyScale(table[SkGetPackedA32(l)], SkGetPackedR32(l)); 31 } 32 33 template<> uint32_t getValue<SkDisplacementMapEffect::kG_ChannelSelectorType>( 34 SkColor l, const SkUnPreMultiply::Scale* table) { 35 return SkUnPreMultiply::ApplyScale(table[SkGetPackedA32(l)], SkGetPackedG32(l)); 36 } 37 38 template<> uint32_t getValue<SkDisplacementMapEffect::kB_ChannelSelectorType>( 39 SkColor l, const SkUnPreMultiply::Scale* table) { 40 return SkUnPreMultiply::ApplyScale(table[SkGetPackedA32(l)], SkGetPackedB32(l)); 41 } 42 43 template<> uint32_t getValue<SkDisplacementMapEffect::kA_ChannelSelectorType>( 44 SkColor l, const SkUnPreMultiply::Scale*) { 45 return SkGetPackedA32(l); 46 } 47 48 template<SkDisplacementMapEffect::ChannelSelectorType typeX, 49 SkDisplacementMapEffect::ChannelSelectorType typeY> 50 void computeDisplacement(SkScalar scale, SkBitmap* dst, SkBitmap* displ, SkBitmap* src) 51 { 52 static const SkScalar Inv8bit = SkScalarDiv(SK_Scalar1, SkFloatToScalar(255.0f)); 53 static const SkScalar Half8bit = SkFloatToScalar(255.0f * 0.5f); 54 const int dstW = displ->width(); 55 const int dstH = displ->height(); 56 const int srcW = src->width(); 57 const int srcH = src->height(); 58 const SkScalar scaleX = SkScalarMul(SkScalarMul(scale, SkIntToScalar(dstW)), Inv8bit); 59 const SkScalar scaleY = SkScalarMul(SkScalarMul(scale, SkIntToScalar(dstH)), Inv8bit); 60 const SkUnPreMultiply::Scale* table = SkUnPreMultiply::GetScaleTable(); 61 for (int y = 0; y < dstH; ++y) { 62 const SkPMColor* displPtr = displ->getAddr32(0, y); 63 SkPMColor* dstPtr = dst->getAddr32(0, y); 64 for (int x = 0; x < dstW; ++x, ++displPtr, ++dstPtr) { 65 const SkScalar displX = 66 SkScalarMul(scaleX, SkIntToScalar(getValue<typeX>(*displPtr, table))-Half8bit); 67 const SkScalar displY = 68 SkScalarMul(scaleY, SkIntToScalar(getValue<typeY>(*displPtr, table))-Half8bit); 69 const int coordX = x + SkScalarRoundToInt(displX); 70 const int coordY = y + SkScalarRoundToInt(displY); 71 *dstPtr = ((coordX < 0) || (coordX >= srcW) || (coordY < 0) || (coordY >= srcH)) ? 72 0 : *(src->getAddr32(coordX, coordY)); 73 } 74 } 75 } 76 77 template<SkDisplacementMapEffect::ChannelSelectorType typeX> 78 void computeDisplacement(SkDisplacementMapEffect::ChannelSelectorType yChannelSelector, 79 SkScalar scale, SkBitmap* dst, SkBitmap* displ, SkBitmap* src) 80 { 81 switch (yChannelSelector) { 82 case SkDisplacementMapEffect::kR_ChannelSelectorType: 83 computeDisplacement<typeX, SkDisplacementMapEffect::kR_ChannelSelectorType>( 84 scale, dst, displ, src); 85 break; 86 case SkDisplacementMapEffect::kG_ChannelSelectorType: 87 computeDisplacement<typeX, SkDisplacementMapEffect::kG_ChannelSelectorType>( 88 scale, dst, displ, src); 89 break; 90 case SkDisplacementMapEffect::kB_ChannelSelectorType: 91 computeDisplacement<typeX, SkDisplacementMapEffect::kB_ChannelSelectorType>( 92 scale, dst, displ, src); 93 break; 94 case SkDisplacementMapEffect::kA_ChannelSelectorType: 95 computeDisplacement<typeX, SkDisplacementMapEffect::kA_ChannelSelectorType>( 96 scale, dst, displ, src); 97 break; 98 case SkDisplacementMapEffect::kUnknown_ChannelSelectorType: 99 default: 100 SkASSERT(!"Unknown Y channel selector"); 101 } 102 } 103 104 void computeDisplacement(SkDisplacementMapEffect::ChannelSelectorType xChannelSelector, 105 SkDisplacementMapEffect::ChannelSelectorType yChannelSelector, 106 SkScalar scale, SkBitmap* dst, SkBitmap* displ, SkBitmap* src) 107 { 108 switch (xChannelSelector) { 109 case SkDisplacementMapEffect::kR_ChannelSelectorType: 110 computeDisplacement<SkDisplacementMapEffect::kR_ChannelSelectorType>( 111 yChannelSelector, scale, dst, displ, src); 112 break; 113 case SkDisplacementMapEffect::kG_ChannelSelectorType: 114 computeDisplacement<SkDisplacementMapEffect::kG_ChannelSelectorType>( 115 yChannelSelector, scale, dst, displ, src); 116 break; 117 case SkDisplacementMapEffect::kB_ChannelSelectorType: 118 computeDisplacement<SkDisplacementMapEffect::kB_ChannelSelectorType>( 119 yChannelSelector, scale, dst, displ, src); 120 break; 121 case SkDisplacementMapEffect::kA_ChannelSelectorType: 122 computeDisplacement<SkDisplacementMapEffect::kA_ChannelSelectorType>( 123 yChannelSelector, scale, dst, displ, src); 124 break; 125 case SkDisplacementMapEffect::kUnknown_ChannelSelectorType: 126 default: 127 SkASSERT(!"Unknown X channel selector"); 128 } 129 } 130 131 } // end namespace 132 133 /////////////////////////////////////////////////////////////////////////////// 134 135 SkDisplacementMapEffect::SkDisplacementMapEffect(ChannelSelectorType xChannelSelector, 136 ChannelSelectorType yChannelSelector, 137 SkScalar scale, 138 SkImageFilter* displacement, 139 SkImageFilter* color) 140 : INHERITED(displacement, color) 141 , fXChannelSelector(xChannelSelector) 142 , fYChannelSelector(yChannelSelector) 143 , fScale(scale) 144 { 145 } 146 147 SkDisplacementMapEffect::~SkDisplacementMapEffect() { 148 } 149 150 SkDisplacementMapEffect::SkDisplacementMapEffect(SkFlattenableReadBuffer& buffer) 151 : INHERITED(buffer) 152 { 153 fXChannelSelector = (SkDisplacementMapEffect::ChannelSelectorType) buffer.readInt(); 154 fYChannelSelector = (SkDisplacementMapEffect::ChannelSelectorType) buffer.readInt(); 155 fScale = buffer.readScalar(); 156 } 157 158 void SkDisplacementMapEffect::flatten(SkFlattenableWriteBuffer& buffer) const { 159 this->INHERITED::flatten(buffer); 160 buffer.writeInt((int) fXChannelSelector); 161 buffer.writeInt((int) fYChannelSelector); 162 buffer.writeScalar(fScale); 163 } 164 165 bool SkDisplacementMapEffect::onFilterImage(Proxy* proxy, 166 const SkBitmap& src, 167 const SkMatrix& ctm, 168 SkBitmap* dst, 169 SkIPoint* offset) { 170 SkBitmap displ, color = src; 171 SkImageFilter* colorInput = getColorInput(); 172 SkImageFilter* displacementInput = getDisplacementInput(); 173 SkASSERT(NULL != displacementInput); 174 if ((colorInput && !colorInput->filterImage(proxy, src, ctm, &color, offset)) || 175 !displacementInput->filterImage(proxy, src, ctm, &displ, offset)) { 176 return false; 177 } 178 if ((displ.config() != SkBitmap::kARGB_8888_Config) || 179 (color.config() != SkBitmap::kARGB_8888_Config)) { 180 return false; 181 } 182 183 SkAutoLockPixels alp_displacement(displ), alp_color(color); 184 if (!displ.getPixels() || !color.getPixels()) { 185 return false; 186 } 187 dst->setConfig(displ.config(), displ.width(), displ.height()); 188 dst->allocPixels(); 189 if (!dst->getPixels()) { 190 return false; 191 } 192 193 computeDisplacement(fXChannelSelector, fYChannelSelector, fScale, dst, &displ, &color); 194 195 return true; 196 } 197 198 /////////////////////////////////////////////////////////////////////////////// 199 200 #if SK_SUPPORT_GPU 201 class GrGLDisplacementMapEffect : public GrGLEffect { 202 public: 203 GrGLDisplacementMapEffect(const GrBackendEffectFactory& factory, 204 const GrEffectRef& effect); 205 virtual ~GrGLDisplacementMapEffect(); 206 207 virtual void emitCode(GrGLShaderBuilder*, 208 const GrEffectStage&, 209 EffectKey, 210 const char* vertexCoords, 211 const char* outputColor, 212 const char* inputColor, 213 const TextureSamplerArray&) SK_OVERRIDE; 214 215 static inline EffectKey GenKey(const GrEffectStage&, const GrGLCaps&); 216 217 virtual void setData(const GrGLUniformManager&, const GrEffectStage&); 218 219 private: 220 SkDisplacementMapEffect::ChannelSelectorType fXChannelSelector; 221 SkDisplacementMapEffect::ChannelSelectorType fYChannelSelector; 222 GrGLEffectMatrix fDisplacementEffectMatrix; 223 GrGLEffectMatrix fColorEffectMatrix; 224 GrGLUniformManager::UniformHandle fScaleUni; 225 GrGLUniformManager::UniformHandle fYSignColor; 226 GrGLUniformManager::UniformHandle fYSignDispl; 227 228 typedef GrGLEffect INHERITED; 229 }; 230 231 /////////////////////////////////////////////////////////////////////////////// 232 233 class GrDisplacementMapEffect : public GrEffect { 234 public: 235 static GrEffectRef* Create(SkDisplacementMapEffect::ChannelSelectorType xChannelSelector, 236 SkDisplacementMapEffect::ChannelSelectorType yChannelSelector, 237 SkScalar scale, GrTexture* displacement, GrTexture* color) { 238 AutoEffectUnref effect(SkNEW_ARGS(GrDisplacementMapEffect, (xChannelSelector, 239 yChannelSelector, 240 scale, 241 displacement, 242 color))); 243 return CreateEffectRef(effect); 244 } 245 246 virtual ~GrDisplacementMapEffect(); 247 248 const GrBackendEffectFactory& getFactory() const; 249 SkDisplacementMapEffect::ChannelSelectorType xChannelSelector() const 250 { return fXChannelSelector; } 251 SkDisplacementMapEffect::ChannelSelectorType yChannelSelector() const 252 { return fYChannelSelector; } 253 SkScalar scale() const { return fScale; } 254 255 typedef GrGLDisplacementMapEffect GLEffect; 256 static const char* Name() { return "DisplacementMap"; } 257 258 void getConstantColorComponents(GrColor* color, uint32_t* validFlags) const SK_OVERRIDE; 259 260 private: 261 virtual bool onIsEqual(const GrEffect&) const SK_OVERRIDE; 262 263 GrDisplacementMapEffect(SkDisplacementMapEffect::ChannelSelectorType xChannelSelector, 264 SkDisplacementMapEffect::ChannelSelectorType yChannelSelector, 265 SkScalar scale, GrTexture* displacement, GrTexture* color); 266 267 GR_DECLARE_EFFECT_TEST; 268 269 GrTextureAccess fDisplacementAccess; 270 GrTextureAccess fColorAccess; 271 SkDisplacementMapEffect::ChannelSelectorType fXChannelSelector; 272 SkDisplacementMapEffect::ChannelSelectorType fYChannelSelector; 273 SkScalar fScale; 274 275 typedef GrEffect INHERITED; 276 }; 277 278 bool SkDisplacementMapEffect::filterImageGPU(Proxy* proxy, const SkBitmap& src, SkBitmap* result) { 279 SkBitmap colorBM; 280 if (!SkImageFilterUtils::GetInputResultGPU(getColorInput(), proxy, src, &colorBM)) { 281 return false; 282 } 283 GrTexture* color = (GrTexture*) colorBM.getTexture(); 284 SkBitmap displacementBM; 285 if (!SkImageFilterUtils::GetInputResultGPU(getDisplacementInput(), proxy, src, &displacementBM)) { 286 return false; 287 } 288 GrTexture* displacement = (GrTexture*) displacementBM.getTexture(); 289 GrContext* context = color->getContext(); 290 291 GrTextureDesc desc; 292 desc.fFlags = kRenderTarget_GrTextureFlagBit | kNoStencil_GrTextureFlagBit; 293 desc.fWidth = src.width(); 294 desc.fHeight = src.height(); 295 desc.fConfig = kSkia8888_GrPixelConfig; 296 297 GrAutoScratchTexture ast(context, desc); 298 SkAutoTUnref<GrTexture> dst(ast.detach()); 299 300 GrContext::AutoRenderTarget art(context, dst->asRenderTarget()); 301 302 GrPaint paint; 303 paint.colorStage(0)->setEffect( 304 GrDisplacementMapEffect::Create(fXChannelSelector, 305 fYChannelSelector, 306 fScale, 307 displacement, 308 color))->unref(); 309 SkRect srcRect; 310 src.getBounds(&srcRect); 311 context->drawRect(paint, srcRect); 312 return SkImageFilterUtils::WrapTexture(dst, src.width(), src.height(), result); 313 } 314 315 /////////////////////////////////////////////////////////////////////////////// 316 317 GrDisplacementMapEffect::GrDisplacementMapEffect( 318 SkDisplacementMapEffect::ChannelSelectorType xChannelSelector, 319 SkDisplacementMapEffect::ChannelSelectorType yChannelSelector, 320 SkScalar scale, 321 GrTexture* displacement, 322 GrTexture* color) 323 : fDisplacementAccess(displacement) 324 , fColorAccess(color) 325 , fXChannelSelector(xChannelSelector) 326 , fYChannelSelector(yChannelSelector) 327 , fScale(scale) { 328 this->addTextureAccess(&fDisplacementAccess); 329 this->addTextureAccess(&fColorAccess); 330 } 331 332 GrDisplacementMapEffect::~GrDisplacementMapEffect() { 333 } 334 335 bool GrDisplacementMapEffect::onIsEqual(const GrEffect& sBase) const { 336 const GrDisplacementMapEffect& s = CastEffect<GrDisplacementMapEffect>(sBase); 337 return fDisplacementAccess.getTexture() == s.fDisplacementAccess.getTexture() && 338 fColorAccess.getTexture() == s.fColorAccess.getTexture() && 339 fXChannelSelector == s.fXChannelSelector && 340 fYChannelSelector == s.fYChannelSelector && 341 fScale == s.fScale; 342 } 343 344 const GrBackendEffectFactory& GrDisplacementMapEffect::getFactory() const { 345 return GrTBackendEffectFactory<GrDisplacementMapEffect>::getInstance(); 346 } 347 348 void GrDisplacementMapEffect::getConstantColorComponents(GrColor* color, 349 uint32_t* validFlags) const { 350 // Any displacement offset bringing a pixel out of bounds will output a color of (0,0,0,0), 351 // so the only way we'd get a constant alpha is if the input color image has a constant alpha 352 // and no displacement offset push any texture coordinates out of bounds OR if the constant 353 // alpha is 0. Since this isn't trivial to compute at this point, let's assume the output is 354 // not of constant color when a displacement effect is applied. 355 *validFlags = 0; 356 } 357 358 /////////////////////////////////////////////////////////////////////////////// 359 360 GR_DEFINE_EFFECT_TEST(GrDisplacementMapEffect); 361 362 GrEffectRef* GrDisplacementMapEffect::TestCreate(SkRandom* random, 363 GrContext* context, 364 GrTexture* textures[]) { 365 int texIdxDispl = random->nextBool() ? GrEffectUnitTest::kSkiaPMTextureIdx : 366 GrEffectUnitTest::kAlphaTextureIdx; 367 int texIdxColor = random->nextBool() ? GrEffectUnitTest::kSkiaPMTextureIdx : 368 GrEffectUnitTest::kAlphaTextureIdx; 369 static const int kMaxComponent = 4; 370 SkDisplacementMapEffect::ChannelSelectorType xChannelSelector = 371 static_cast<SkDisplacementMapEffect::ChannelSelectorType>( 372 random->nextRangeU(1, kMaxComponent)); 373 SkDisplacementMapEffect::ChannelSelectorType yChannelSelector = 374 static_cast<SkDisplacementMapEffect::ChannelSelectorType>( 375 random->nextRangeU(1, kMaxComponent)); 376 SkScalar scale = random->nextUScalar1(); 377 378 return GrDisplacementMapEffect::Create(xChannelSelector, yChannelSelector, scale, 379 textures[texIdxDispl], textures[texIdxColor]); 380 } 381 382 /////////////////////////////////////////////////////////////////////////////// 383 384 GrGLDisplacementMapEffect::GrGLDisplacementMapEffect(const GrBackendEffectFactory& factory, 385 const GrEffectRef& effect) 386 : INHERITED(factory) 387 , fXChannelSelector(CastEffect<GrDisplacementMapEffect>(effect).xChannelSelector()) 388 , fYChannelSelector(CastEffect<GrDisplacementMapEffect>(effect).yChannelSelector()) { 389 } 390 391 GrGLDisplacementMapEffect::~GrGLDisplacementMapEffect() { 392 } 393 394 void GrGLDisplacementMapEffect::emitCode(GrGLShaderBuilder* builder, 395 const GrEffectStage&, 396 EffectKey key, 397 const char* vertexCoords, 398 const char* outputColor, 399 const char* inputColor, 400 const TextureSamplerArray& samplers) { 401 fScaleUni = builder->addUniform(GrGLShaderBuilder::kFragment_ShaderType, 402 kVec2f_GrSLType, "Scale"); 403 const char* scaleUni = builder->getUniformCStr(fScaleUni); 404 405 const char* dCoordsIn; 406 GrSLType dCoordsType = fDisplacementEffectMatrix.emitCode( 407 builder, key, vertexCoords, &dCoordsIn, NULL, "DISPL"); 408 const char* cCoordsIn; 409 GrSLType cCoordsType = fColorEffectMatrix.emitCode( 410 builder, key, vertexCoords, &cCoordsIn, NULL, "COLOR"); 411 412 SkString* code = &builder->fFSCode; 413 const char* dColor = "dColor"; 414 const char* cCoords = "cCoords"; 415 const char* nearZero = "1e-6"; // Since 6.10352e5 is the smallest half float, use 416 // a number smaller than that to approximate 0, but 417 // leave room for 32-bit float GPU rounding errors. 418 419 code->appendf("\t\tvec4 %s = ", dColor); 420 builder->appendTextureLookup(code, samplers[0], dCoordsIn, dCoordsType); 421 code->append(";\n"); 422 423 // Unpremultiply the displacement 424 code->appendf("\t\t%s.rgb = (%s.a < %s) ? vec3(0.0) : clamp(%s.rgb / %s.a, 0.0, 1.0);", 425 dColor, dColor, nearZero, dColor, dColor); 426 427 code->appendf("\t\tvec2 %s = %s + %s*(%s.", 428 cCoords, cCoordsIn, scaleUni, dColor); 429 430 switch (fXChannelSelector) { 431 case SkDisplacementMapEffect::kR_ChannelSelectorType: 432 code->append("r"); 433 break; 434 case SkDisplacementMapEffect::kG_ChannelSelectorType: 435 code->append("g"); 436 break; 437 case SkDisplacementMapEffect::kB_ChannelSelectorType: 438 code->append("b"); 439 break; 440 case SkDisplacementMapEffect::kA_ChannelSelectorType: 441 code->append("a"); 442 break; 443 case SkDisplacementMapEffect::kUnknown_ChannelSelectorType: 444 default: 445 SkASSERT(!"Unknown X channel selector"); 446 } 447 448 switch (fYChannelSelector) { 449 case SkDisplacementMapEffect::kR_ChannelSelectorType: 450 code->append("r"); 451 break; 452 case SkDisplacementMapEffect::kG_ChannelSelectorType: 453 code->append("g"); 454 break; 455 case SkDisplacementMapEffect::kB_ChannelSelectorType: 456 code->append("b"); 457 break; 458 case SkDisplacementMapEffect::kA_ChannelSelectorType: 459 code->append("a"); 460 break; 461 case SkDisplacementMapEffect::kUnknown_ChannelSelectorType: 462 default: 463 SkASSERT(!"Unknown Y channel selector"); 464 } 465 code->append("-vec2(0.5));\t\t"); 466 467 // FIXME : This can be achieved with a "clamp to border" texture repeat mode and 468 // a 0 border color instead of computing if cCoords is out of bounds here. 469 code->appendf( 470 "%s = any(greaterThan(vec4(vec2(0.0), %s), vec4(%s, vec2(1.0)))) ? vec4(0.0) : ", 471 outputColor, cCoords, cCoords); 472 builder->appendTextureLookup(code, samplers[1], cCoords, cCoordsType); 473 code->append(";\n"); 474 } 475 476 void GrGLDisplacementMapEffect::setData(const GrGLUniformManager& uman, const GrEffectStage& stage) { 477 const GrDisplacementMapEffect& displacementMap = GetEffectFromStage<GrDisplacementMapEffect>(stage); 478 GrTexture* displTex = displacementMap.texture(0); 479 GrTexture* colorTex = displacementMap.texture(1); 480 fDisplacementEffectMatrix.setData(uman, 481 GrEffect::MakeDivByTextureWHMatrix(displTex), 482 stage.getCoordChangeMatrix(), 483 displTex); 484 fColorEffectMatrix.setData(uman, 485 GrEffect::MakeDivByTextureWHMatrix(colorTex), 486 stage.getCoordChangeMatrix(), 487 colorTex); 488 489 uman.set2f(fScaleUni, SkScalarToFloat(displacementMap.scale()), 490 colorTex->origin() == kTopLeft_GrSurfaceOrigin ? 491 SkScalarToFloat(displacementMap.scale()) : 492 SkScalarToFloat(-displacementMap.scale())); 493 } 494 495 GrGLEffect::EffectKey GrGLDisplacementMapEffect::GenKey(const GrEffectStage& stage, 496 const GrGLCaps&) { 497 const GrDisplacementMapEffect& displacementMap = 498 GetEffectFromStage<GrDisplacementMapEffect>(stage); 499 500 GrTexture* displTex = displacementMap.texture(0); 501 GrTexture* colorTex = displacementMap.texture(1); 502 503 EffectKey displKey = GrGLEffectMatrix::GenKey(GrEffect::MakeDivByTextureWHMatrix(displTex), 504 stage.getCoordChangeMatrix(), 505 displTex); 506 507 EffectKey colorKey = GrGLEffectMatrix::GenKey(GrEffect::MakeDivByTextureWHMatrix(colorTex), 508 stage.getCoordChangeMatrix(), 509 colorTex); 510 511 colorKey <<= GrGLEffectMatrix::kKeyBits; 512 EffectKey xKey = displacementMap.xChannelSelector() << (2 * GrGLEffectMatrix::kKeyBits); 513 EffectKey yKey = displacementMap.yChannelSelector() << (2 * GrGLEffectMatrix::kKeyBits + 514 SkDisplacementMapEffect::kKeyBits); 515 516 return xKey | yKey | displKey | colorKey; 517 } 518 #endif 519