1 /* 2 * Copyright 2012 The Android Open Source Project 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 "SkBitmap.h" 9 #include "SkMagnifierImageFilter.h" 10 #include "SkColorPriv.h" 11 #include "SkFlattenableBuffers.h" 12 13 //////////////////////////////////////////////////////////////////////////////// 14 #if SK_SUPPORT_GPU 15 #include "effects/GrSingleTextureEffect.h" 16 #include "gl/GrGLEffect.h" 17 #include "gl/GrGLEffectMatrix.h" 18 #include "gl/GrGLSL.h" 19 #include "gl/GrGLTexture.h" 20 #include "GrTBackendEffectFactory.h" 21 22 class GrGLMagnifierEffect; 23 24 class GrMagnifierEffect : public GrSingleTextureEffect { 25 26 public: 27 static GrEffectRef* Create(GrTexture* texture, 28 float xOffset, 29 float yOffset, 30 float xZoom, 31 float yZoom, 32 float xInset, 33 float yInset) { 34 AutoEffectUnref effect(SkNEW_ARGS(GrMagnifierEffect, (texture, 35 xOffset, 36 yOffset, 37 xZoom, 38 yZoom, 39 xInset, 40 yInset))); 41 return CreateEffectRef(effect); 42 } 43 44 virtual ~GrMagnifierEffect() {}; 45 46 static const char* Name() { return "Magnifier"; } 47 48 virtual const GrBackendEffectFactory& getFactory() const SK_OVERRIDE; 49 virtual void getConstantColorComponents(GrColor* color, uint32_t* validFlags) const SK_OVERRIDE; 50 51 float x_offset() const { return fXOffset; } 52 float y_offset() const { return fYOffset; } 53 float x_zoom() const { return fXZoom; } 54 float y_zoom() const { return fYZoom; } 55 float x_inset() const { return fXInset; } 56 float y_inset() const { return fYInset; } 57 58 typedef GrGLMagnifierEffect GLEffect; 59 60 private: 61 GrMagnifierEffect(GrTexture* texture, 62 float xOffset, 63 float yOffset, 64 float xZoom, 65 float yZoom, 66 float xInset, 67 float yInset) 68 : GrSingleTextureEffect(texture, MakeDivByTextureWHMatrix(texture)) 69 , fXOffset(xOffset) 70 , fYOffset(yOffset) 71 , fXZoom(xZoom) 72 , fYZoom(yZoom) 73 , fXInset(xInset) 74 , fYInset(yInset) {} 75 76 virtual bool onIsEqual(const GrEffect&) const SK_OVERRIDE; 77 78 GR_DECLARE_EFFECT_TEST; 79 80 float fXOffset; 81 float fYOffset; 82 float fXZoom; 83 float fYZoom; 84 float fXInset; 85 float fYInset; 86 87 typedef GrSingleTextureEffect INHERITED; 88 }; 89 90 // For brevity 91 typedef GrGLUniformManager::UniformHandle UniformHandle; 92 93 class GrGLMagnifierEffect : public GrGLEffect { 94 public: 95 GrGLMagnifierEffect(const GrBackendEffectFactory& factory, const GrEffectRef& effect); 96 97 virtual void emitCode(GrGLShaderBuilder*, 98 const GrEffectStage&, 99 EffectKey, 100 const char* vertexCoords, 101 const char* outputColor, 102 const char* inputColor, 103 const TextureSamplerArray&) SK_OVERRIDE; 104 105 virtual void setData(const GrGLUniformManager& uman, const GrEffectStage& stage) SK_OVERRIDE; 106 107 static inline EffectKey GenKey(const GrEffectStage&, const GrGLCaps&); 108 109 private: 110 111 UniformHandle fOffsetVar; 112 UniformHandle fZoomVar; 113 UniformHandle fInsetVar; 114 115 GrGLEffectMatrix fEffectMatrix; 116 117 typedef GrGLEffect INHERITED; 118 }; 119 120 GrGLMagnifierEffect::GrGLMagnifierEffect(const GrBackendEffectFactory& factory, const GrEffectRef&) 121 : INHERITED(factory) 122 , fOffsetVar(GrGLUniformManager::kInvalidUniformHandle) 123 , fZoomVar(GrGLUniformManager::kInvalidUniformHandle) 124 , fInsetVar(GrGLUniformManager::kInvalidUniformHandle) { 125 } 126 127 void GrGLMagnifierEffect::emitCode(GrGLShaderBuilder* builder, 128 const GrEffectStage&, 129 EffectKey key, 130 const char* vertexCoords, 131 const char* outputColor, 132 const char* inputColor, 133 const TextureSamplerArray& samplers) { 134 const char* coords; 135 fEffectMatrix.emitCodeMakeFSCoords2D(builder, key, vertexCoords, &coords); 136 fOffsetVar = builder->addUniform( 137 GrGLShaderBuilder::kFragment_ShaderType | 138 GrGLShaderBuilder::kVertex_ShaderType, 139 kVec2f_GrSLType, "uOffset"); 140 fZoomVar = builder->addUniform( 141 GrGLShaderBuilder::kFragment_ShaderType | 142 GrGLShaderBuilder::kVertex_ShaderType, 143 kVec2f_GrSLType, "uZoom"); 144 fInsetVar = builder->addUniform( 145 GrGLShaderBuilder::kFragment_ShaderType | 146 GrGLShaderBuilder::kVertex_ShaderType, 147 kVec2f_GrSLType, "uInset"); 148 149 SkString* code = &builder->fFSCode; 150 151 code->appendf("\t\tvec2 coord = %s;\n", coords); 152 code->appendf("\t\tvec2 zoom_coord = %s + %s / %s;\n", 153 builder->getUniformCStr(fOffsetVar), 154 coords, 155 builder->getUniformCStr(fZoomVar)); 156 157 code->appendf("\t\tvec2 delta = min(coord, vec2(1.0, 1.0) - coord);\n"); 158 159 code->appendf("\t\tdelta = delta / %s;\n", builder->getUniformCStr(fInsetVar)); 160 161 code->appendf("\t\tfloat weight = 0.0;\n"); 162 code->appendf("\t\tif (delta.s < 2.0 && delta.t < 2.0) {\n"); 163 code->appendf("\t\t\tdelta = vec2(2.0, 2.0) - delta;\n"); 164 code->appendf("\t\t\tfloat dist = length(delta);\n"); 165 code->appendf("\t\t\tdist = max(2.0 - dist, 0.0);\n"); 166 code->appendf("\t\t\tweight = min(dist * dist, 1.0);\n"); 167 code->appendf("\t\t} else {\n"); 168 code->appendf("\t\t\tvec2 delta_squared = delta * delta;\n"); 169 code->appendf("\t\t\tweight = min(min(delta_squared.s, delta_squared.y), 1.0);\n"); 170 code->appendf("\t\t}\n"); 171 172 code->appendf("\t\tvec2 mix_coord = mix(coord, zoom_coord, weight);\n"); 173 code->appendf("\t\tvec4 output_color = "); 174 builder->appendTextureLookup(code, samplers[0], "mix_coord"); 175 code->append(";\n"); 176 177 code->appendf("\t\t%s = output_color;", outputColor); 178 GrGLSLMulVarBy4f(code, 2, outputColor, inputColor); 179 } 180 181 void GrGLMagnifierEffect::setData(const GrGLUniformManager& uman, 182 const GrEffectStage& stage) { 183 const GrMagnifierEffect& zoom = GetEffectFromStage<GrMagnifierEffect>(stage); 184 uman.set2f(fOffsetVar, zoom.x_offset(), zoom.y_offset()); 185 uman.set2f(fZoomVar, zoom.x_zoom(), zoom.y_zoom()); 186 uman.set2f(fInsetVar, zoom.x_inset(), zoom.y_inset()); 187 fEffectMatrix.setData(uman, zoom.getMatrix(), stage.getCoordChangeMatrix(), zoom.texture(0)); 188 } 189 190 GrGLEffect::EffectKey GrGLMagnifierEffect::GenKey(const GrEffectStage& stage, const GrGLCaps&) { 191 const GrMagnifierEffect& zoom = GetEffectFromStage<GrMagnifierEffect>(stage); 192 return GrGLEffectMatrix::GenKey(zoom.getMatrix(), 193 stage.getCoordChangeMatrix(), 194 zoom.texture(0)); 195 } 196 197 ///////////////////////////////////////////////////////////////////// 198 199 GR_DEFINE_EFFECT_TEST(GrMagnifierEffect); 200 201 GrEffectRef* GrMagnifierEffect::TestCreate(SkRandom* random, 202 GrContext* context, 203 GrTexture** textures) { 204 const int kMaxWidth = 200; 205 const int kMaxHeight = 200; 206 const int kMaxInset = 20; 207 uint32_t width = random->nextULessThan(kMaxWidth); 208 uint32_t height = random->nextULessThan(kMaxHeight); 209 uint32_t x = random->nextULessThan(kMaxWidth - width); 210 uint32_t y = random->nextULessThan(kMaxHeight - height); 211 SkScalar inset = SkIntToScalar(random->nextULessThan(kMaxInset)); 212 213 SkAutoTUnref<SkImageFilter> filter( 214 new SkMagnifierImageFilter( 215 SkRect::MakeXYWH(SkIntToScalar(x), SkIntToScalar(y), 216 SkIntToScalar(width), SkIntToScalar(height)), 217 inset)); 218 GrEffectRef* effect; 219 filter->asNewEffect(&effect, textures[0]); 220 GrAssert(NULL != effect); 221 return effect; 222 } 223 224 /////////////////////////////////////////////////////////////////////////////// 225 226 const GrBackendEffectFactory& GrMagnifierEffect::getFactory() const { 227 return GrTBackendEffectFactory<GrMagnifierEffect>::getInstance(); 228 } 229 230 bool GrMagnifierEffect::onIsEqual(const GrEffect& sBase) const { 231 const GrMagnifierEffect& s = CastEffect<GrMagnifierEffect>(sBase); 232 return (this->texture(0) == s.texture(0) && 233 this->fXOffset == s.fXOffset && 234 this->fYOffset == s.fYOffset && 235 this->fXZoom == s.fXZoom && 236 this->fYZoom == s.fYZoom && 237 this->fXInset == s.fXInset && 238 this->fYInset == s.fYInset); 239 } 240 241 void GrMagnifierEffect::getConstantColorComponents(GrColor* color, uint32_t* validFlags) const { 242 this->updateConstantColorComponentsForModulation(color, validFlags); 243 } 244 245 #endif 246 247 //////////////////////////////////////////////////////////////////////////////// 248 SkMagnifierImageFilter::SkMagnifierImageFilter(SkFlattenableReadBuffer& buffer) 249 : INHERITED(buffer) { 250 float x = buffer.readScalar(); 251 float y = buffer.readScalar(); 252 float width = buffer.readScalar(); 253 float height = buffer.readScalar(); 254 fSrcRect = SkRect::MakeXYWH(x, y, width, height); 255 fInset = buffer.readScalar(); 256 } 257 258 // FIXME: implement single-input semantics 259 SkMagnifierImageFilter::SkMagnifierImageFilter(SkRect srcRect, SkScalar inset) 260 : INHERITED(0), fSrcRect(srcRect), fInset(inset) { 261 SkASSERT(srcRect.x() >= 0 && srcRect.y() >= 0 && inset >= 0); 262 } 263 264 bool SkMagnifierImageFilter::asNewEffect(GrEffectRef** effect, GrTexture* texture) const { 265 #if SK_SUPPORT_GPU 266 if (effect) { 267 *effect = GrMagnifierEffect::Create(texture, 268 fSrcRect.x() / texture->width(), 269 fSrcRect.y() / texture->height(), 270 texture->width() / fSrcRect.width(), 271 texture->height() / fSrcRect.height(), 272 fInset / texture->width(), 273 fInset / texture->height()); 274 } 275 return true; 276 #else 277 return false; 278 #endif 279 } 280 281 void SkMagnifierImageFilter::flatten(SkFlattenableWriteBuffer& buffer) const { 282 this->INHERITED::flatten(buffer); 283 buffer.writeScalar(fSrcRect.x()); 284 buffer.writeScalar(fSrcRect.y()); 285 buffer.writeScalar(fSrcRect.width()); 286 buffer.writeScalar(fSrcRect.height()); 287 buffer.writeScalar(fInset); 288 } 289 290 bool SkMagnifierImageFilter::onFilterImage(Proxy*, const SkBitmap& src, 291 const SkMatrix&, SkBitmap* dst, 292 SkIPoint* offset) { 293 SkASSERT(src.config() == SkBitmap::kARGB_8888_Config); 294 SkASSERT(fSrcRect.width() < src.width()); 295 SkASSERT(fSrcRect.height() < src.height()); 296 297 if (src.config() != SkBitmap::kARGB_8888_Config) { 298 return false; 299 } 300 301 SkAutoLockPixels alp(src); 302 SkASSERT(src.getPixels()); 303 if (!src.getPixels() || src.width() <= 0 || src.height() <= 0) { 304 return false; 305 } 306 307 SkScalar inv_inset = fInset > 0 ? SkScalarInvert(fInset) : SK_Scalar1; 308 309 SkScalar inv_x_zoom = fSrcRect.width() / src.width(); 310 SkScalar inv_y_zoom = fSrcRect.height() / src.height(); 311 312 dst->setConfig(src.config(), src.width(), src.height()); 313 dst->allocPixels(); 314 SkColor* sptr = src.getAddr32(0, 0); 315 SkColor* dptr = dst->getAddr32(0, 0); 316 int width = src.width(), height = src.height(); 317 for (int y = 0; y < height; ++y) { 318 for (int x = 0; x < width; ++x) { 319 SkScalar x_dist = SkMin32(x, width - x - 1) * inv_inset; 320 SkScalar y_dist = SkMin32(y, height - y - 1) * inv_inset; 321 SkScalar weight = 0; 322 323 static const SkScalar kScalar2 = SkScalar(2); 324 325 // To create a smooth curve at the corners, we need to work on 326 // a square twice the size of the inset. 327 if (x_dist < kScalar2 && y_dist < kScalar2) { 328 x_dist = kScalar2 - x_dist; 329 y_dist = kScalar2 - y_dist; 330 331 SkScalar dist = SkScalarSqrt(SkScalarSquare(x_dist) + 332 SkScalarSquare(y_dist)); 333 dist = SkMaxScalar(kScalar2 - dist, 0); 334 weight = SkMinScalar(SkScalarSquare(dist), SK_Scalar1); 335 } else { 336 SkScalar sqDist = SkMinScalar(SkScalarSquare(x_dist), 337 SkScalarSquare(y_dist)); 338 weight = SkMinScalar(sqDist, SK_Scalar1); 339 } 340 341 SkScalar x_interp = SkScalarMul(weight, (fSrcRect.x() + x * inv_x_zoom)) + 342 (SK_Scalar1 - weight) * x; 343 SkScalar y_interp = SkScalarMul(weight, (fSrcRect.y() + y * inv_y_zoom)) + 344 (SK_Scalar1 - weight) * y; 345 346 int x_val = SkMin32(SkScalarFloorToInt(x_interp), width - 1); 347 int y_val = SkMin32(SkScalarFloorToInt(y_interp), height - 1); 348 349 *dptr = sptr[y_val * width + x_val]; 350 dptr++; 351 } 352 } 353 return true; 354 } 355