SkiaShader.cpp revision 6183c97e5f317ad52ad16fe50e40129e2c7b2150
1/* 2 * Copyright (C) 2010 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17#include "SkiaShader.h" 18 19#include "Caches.h" 20#include "Extensions.h" 21#include "Matrix.h" 22#include "Texture.h" 23#include "hwui/Bitmap.h" 24 25#include <SkMatrix.h> 26#include <utils/Log.h> 27 28namespace android { 29namespace uirenderer { 30 31/////////////////////////////////////////////////////////////////////////////// 32// Support 33/////////////////////////////////////////////////////////////////////////////// 34 35static constexpr GLenum gTileModes[] = { 36 GL_CLAMP_TO_EDGE, // == SkShader::kClamp_TileMode 37 GL_REPEAT, // == SkShader::kRepeat_Mode 38 GL_MIRRORED_REPEAT // == SkShader::kMirror_TileMode 39}; 40 41static_assert(gTileModes[SkShader::kClamp_TileMode] == GL_CLAMP_TO_EDGE, 42 "SkShader TileModes have changed"); 43static_assert(gTileModes[SkShader::kRepeat_TileMode] == GL_REPEAT, 44 "SkShader TileModes have changed"); 45static_assert(gTileModes[SkShader::kMirror_TileMode] == GL_MIRRORED_REPEAT, 46 "SkShader TileModes have changed"); 47 48/** 49 * This function does not work for n == 0. 50 */ 51static inline bool isPowerOfTwo(unsigned int n) { 52 return !(n & (n - 1)); 53} 54 55static inline void bindUniformColor(int slot, FloatColor color) { 56 glUniform4fv(slot, 1, reinterpret_cast<const float*>(&color)); 57} 58 59static inline void bindTexture(Caches* caches, Texture* texture, GLenum wrapS, GLenum wrapT) { 60 caches->textureState().bindTexture(texture->target(), texture->id()); 61 texture->setWrapST(wrapS, wrapT); 62} 63 64/** 65 * Compute the matrix to transform to screen space. 66 * @param screenSpace Output param for the computed matrix. 67 * @param unitMatrix The unit matrix for gradient shaders, as returned by SkShader::asAGradient, 68 * or identity. 69 * @param localMatrix Local matrix, as returned by SkShader::getLocalMatrix(). 70 * @param modelViewMatrix Model view matrix, as supplied by the OpenGLRenderer. 71 */ 72static void computeScreenSpaceMatrix(mat4& screenSpace, const SkMatrix& unitMatrix, 73 const SkMatrix& localMatrix, const mat4& modelViewMatrix) { 74 mat4 shaderMatrix; 75 // uses implicit construction 76 shaderMatrix.loadInverse(localMatrix); 77 // again, uses implicit construction 78 screenSpace.loadMultiply(unitMatrix, shaderMatrix); 79 screenSpace.multiply(modelViewMatrix); 80} 81 82/////////////////////////////////////////////////////////////////////////////// 83// Gradient shader matrix helpers 84/////////////////////////////////////////////////////////////////////////////// 85 86static void toLinearUnitMatrix(const SkPoint pts[2], SkMatrix* matrix) { 87 SkVector vec = pts[1] - pts[0]; 88 const float mag = vec.length(); 89 const float inv = mag ? 1.0f / mag : 0; 90 91 vec.scale(inv); 92 matrix->setSinCos(-vec.fY, vec.fX, pts[0].fX, pts[0].fY); 93 matrix->postTranslate(-pts[0].fX, -pts[0].fY); 94 matrix->postScale(inv, inv); 95} 96 97static void toCircularUnitMatrix(const float x, const float y, const float radius, 98 SkMatrix* matrix) { 99 const float inv = 1.0f / radius; 100 matrix->setTranslate(-x, -y); 101 matrix->postScale(inv, inv); 102} 103 104static void toSweepUnitMatrix(const float x, const float y, SkMatrix* matrix) { 105 matrix->setTranslate(-x, -y); 106} 107 108/////////////////////////////////////////////////////////////////////////////// 109// Common gradient code 110/////////////////////////////////////////////////////////////////////////////// 111 112static bool isSimpleGradient(const SkShader::GradientInfo& gradInfo) { 113 return gradInfo.fColorCount == 2 && gradInfo.fTileMode == SkShader::kClamp_TileMode; 114} 115 116/////////////////////////////////////////////////////////////////////////////// 117// Store / apply 118/////////////////////////////////////////////////////////////////////////////// 119 120bool tryStoreGradient(Caches& caches, const SkShader& shader, const Matrix4 modelViewMatrix, 121 GLuint* textureUnit, ProgramDescription* description, 122 SkiaShaderData::GradientShaderData* outData) { 123 SkShader::GradientInfo gradInfo; 124 gradInfo.fColorCount = 0; 125 gradInfo.fColors = nullptr; 126 gradInfo.fColorOffsets = nullptr; 127 128 SkMatrix unitMatrix; 129 switch (shader.asAGradient(&gradInfo)) { 130 case SkShader::kLinear_GradientType: 131 description->gradientType = ProgramDescription::kGradientLinear; 132 133 toLinearUnitMatrix(gradInfo.fPoint, &unitMatrix); 134 break; 135 case SkShader::kRadial_GradientType: 136 description->gradientType = ProgramDescription::kGradientCircular; 137 138 toCircularUnitMatrix(gradInfo.fPoint[0].fX, gradInfo.fPoint[0].fY, 139 gradInfo.fRadius[0], &unitMatrix); 140 break; 141 case SkShader::kSweep_GradientType: 142 description->gradientType = ProgramDescription::kGradientSweep; 143 144 toSweepUnitMatrix(gradInfo.fPoint[0].fX, gradInfo.fPoint[0].fY, &unitMatrix); 145 break; 146 default: 147 // Do nothing. This shader is unsupported. 148 return false; 149 } 150 description->hasGradient = true; 151 description->isSimpleGradient = isSimpleGradient(gradInfo); 152 153 computeScreenSpaceMatrix(outData->screenSpace, unitMatrix, 154 shader.getLocalMatrix(), modelViewMatrix); 155 156 // re-query shader to get full color / offset data 157 std::unique_ptr<SkColor[]> colorStorage(new SkColor[gradInfo.fColorCount]); 158 std::unique_ptr<SkScalar[]> colorOffsets(new SkScalar[gradInfo.fColorCount]); 159 gradInfo.fColors = &colorStorage[0]; 160 gradInfo.fColorOffsets = &colorOffsets[0]; 161 shader.asAGradient(&gradInfo); 162 163 if (CC_UNLIKELY(!description->isSimpleGradient)) { 164 outData->gradientSampler = (*textureUnit)++; 165 166#ifndef SK_SCALAR_IS_FLOAT 167 #error Need to convert gradInfo.fColorOffsets to float! 168#endif 169 outData->gradientTexture = caches.gradientCache.get( 170 gradInfo.fColors, gradInfo.fColorOffsets, gradInfo.fColorCount); 171 outData->wrapST = gTileModes[gradInfo.fTileMode]; 172 } else { 173 outData->gradientSampler = 0; 174 outData->gradientTexture = nullptr; 175 176 outData->startColor.setUnPreMultiplied(gradInfo.fColors[0]); 177 outData->endColor.setUnPreMultiplied(gradInfo.fColors[1]); 178 } 179 180 return true; 181} 182 183void applyGradient(Caches& caches, const SkiaShaderData::GradientShaderData& data, 184 const GLsizei width, const GLsizei height) { 185 186 if (CC_UNLIKELY(data.gradientTexture)) { 187 caches.textureState().activateTexture(data.gradientSampler); 188 bindTexture(&caches, data.gradientTexture, data.wrapST, data.wrapST); 189 glUniform1i(caches.program().getUniform("gradientSampler"), data.gradientSampler); 190 } else { 191 bindUniformColor(caches.program().getUniform("startColor"), data.startColor); 192 bindUniformColor(caches.program().getUniform("endColor"), data.endColor); 193 } 194 195 glUniform2f(caches.program().getUniform("screenSize"), 1.0f / width, 1.0f / height); 196 glUniformMatrix4fv(caches.program().getUniform("screenSpace"), 1, 197 GL_FALSE, &data.screenSpace.data[0]); 198} 199 200bool tryStoreBitmap(Caches& caches, const SkShader& shader, const Matrix4& modelViewMatrix, 201 GLuint* textureUnit, ProgramDescription* description, 202 SkiaShaderData::BitmapShaderData* outData) { 203 SkBitmap bitmap; 204 SkShader::TileMode xy[2]; 205 if (!shader.isABitmap(&bitmap, nullptr, xy)) { 206 return false; 207 } 208 209 // TODO: create hwui-owned BitmapShader. 210 Bitmap* hwuiBitmap = static_cast<Bitmap*>(bitmap.pixelRef()); 211 outData->bitmapTexture = caches.textureCache.get(hwuiBitmap); 212 if (!outData->bitmapTexture) return false; 213 214 outData->bitmapSampler = (*textureUnit)++; 215 216 const float width = outData->bitmapTexture->width(); 217 const float height = outData->bitmapTexture->height(); 218 219 description->hasBitmap = true; 220 description->hasLinearTexture = outData->bitmapTexture->isLinear(); 221 description->isShaderBitmapExternal = hwuiBitmap->isHardware(); 222 // gralloc doesn't support non-clamp modes 223 if (hwuiBitmap->isHardware() || (!caches.extensions().hasNPot() 224 && (!isPowerOfTwo(width) || !isPowerOfTwo(height)) 225 && (xy[0] != SkShader::kClamp_TileMode || xy[1] != SkShader::kClamp_TileMode))) { 226 // need non-clamp mode, but it's not supported for this draw, 227 // so enable custom shader logic to mimic 228 description->useShaderBasedWrap = true; 229 description->bitmapWrapS = gTileModes[xy[0]]; 230 description->bitmapWrapT = gTileModes[xy[1]]; 231 232 outData->wrapS = GL_CLAMP_TO_EDGE; 233 outData->wrapT = GL_CLAMP_TO_EDGE; 234 } else { 235 outData->wrapS = gTileModes[xy[0]]; 236 outData->wrapT = gTileModes[xy[1]]; 237 } 238 239 computeScreenSpaceMatrix(outData->textureTransform, SkMatrix::I(), shader.getLocalMatrix(), 240 modelViewMatrix); 241 outData->textureDimension[0] = 1.0f / width; 242 outData->textureDimension[1] = 1.0f / height; 243 244 return true; 245} 246 247void applyBitmap(Caches& caches, const SkiaShaderData::BitmapShaderData& data) { 248 caches.textureState().activateTexture(data.bitmapSampler); 249 bindTexture(&caches, data.bitmapTexture, data.wrapS, data.wrapT); 250 data.bitmapTexture->setFilter(GL_LINEAR); 251 252 glUniform1i(caches.program().getUniform("bitmapSampler"), data.bitmapSampler); 253 glUniformMatrix4fv(caches.program().getUniform("textureTransform"), 1, GL_FALSE, 254 &data.textureTransform.data[0]); 255 glUniform2fv(caches.program().getUniform("textureDimension"), 1, &data.textureDimension[0]); 256} 257 258SkiaShaderType getComposeSubType(const SkShader& shader) { 259 // First check for a gradient shader. 260 switch (shader.asAGradient(nullptr)) { 261 case SkShader::kNone_GradientType: 262 // Not a gradient shader. Fall through to check for other types. 263 break; 264 case SkShader::kLinear_GradientType: 265 case SkShader::kRadial_GradientType: 266 case SkShader::kSweep_GradientType: 267 return kGradient_SkiaShaderType; 268 default: 269 // This is a Skia gradient that has no SkiaShader equivalent. Return None to skip. 270 return kNone_SkiaShaderType; 271 } 272 273 // The shader is not a gradient. Check for a bitmap shader. 274 if (shader.isABitmap()) { 275 return kBitmap_SkiaShaderType; 276 } 277 return kNone_SkiaShaderType; 278} 279 280void storeCompose(Caches& caches, const SkShader& bitmapShader, const SkShader& gradientShader, 281 const Matrix4& modelViewMatrix, GLuint* textureUnit, 282 ProgramDescription* description, SkiaShaderData* outData) { 283 LOG_ALWAYS_FATAL_IF(!tryStoreBitmap(caches, bitmapShader, modelViewMatrix, 284 textureUnit, description, &outData->bitmapData), 285 "failed storing bitmap shader data"); 286 LOG_ALWAYS_FATAL_IF(!tryStoreGradient(caches, gradientShader, modelViewMatrix, 287 textureUnit, description, &outData->gradientData), 288 "failing storing gradient shader data"); 289} 290 291bool tryStoreCompose(Caches& caches, const SkShader& shader, const Matrix4& modelViewMatrix, 292 GLuint* textureUnit, ProgramDescription* description, 293 SkiaShaderData* outData) { 294 295 SkShader::ComposeRec rec; 296 if (!shader.asACompose(&rec)) return false; 297 298 const SkiaShaderType shaderAType = getComposeSubType(*rec.fShaderA); 299 const SkiaShaderType shaderBType = getComposeSubType(*rec.fShaderB); 300 301 // check that type enum values are the 2 flags that compose the kCompose value 302 if ((shaderAType & shaderBType) != 0) return false; 303 if ((shaderAType | shaderBType) != kCompose_SkiaShaderType) return false; 304 305 mat4 transform; 306 computeScreenSpaceMatrix(transform, SkMatrix::I(), shader.getLocalMatrix(), modelViewMatrix); 307 if (shaderAType == kBitmap_SkiaShaderType) { 308 description->isBitmapFirst = true; 309 storeCompose(caches, *rec.fShaderA, *rec.fShaderB, 310 transform, textureUnit, description, outData); 311 } else { 312 description->isBitmapFirst = false; 313 storeCompose(caches, *rec.fShaderB, *rec.fShaderA, 314 transform, textureUnit, description, outData); 315 } 316 description->shadersMode = rec.fBlendMode; 317 return true; 318} 319 320void SkiaShader::store(Caches& caches, const SkShader& shader, const Matrix4& modelViewMatrix, 321 GLuint* textureUnit, ProgramDescription* description, 322 SkiaShaderData* outData) { 323 if (tryStoreGradient(caches, shader, modelViewMatrix, 324 textureUnit, description, &outData->gradientData)) { 325 outData->skiaShaderType = kGradient_SkiaShaderType; 326 return; 327 } 328 329 if (tryStoreBitmap(caches, shader, modelViewMatrix, 330 textureUnit, description, &outData->bitmapData)) { 331 outData->skiaShaderType = kBitmap_SkiaShaderType; 332 return; 333 } 334 335 if (tryStoreCompose(caches, shader, modelViewMatrix, 336 textureUnit, description, outData)) { 337 outData->skiaShaderType = kCompose_SkiaShaderType; 338 return; 339 } 340 341 // Unknown/unsupported type, so explicitly ignore shader 342 outData->skiaShaderType = kNone_SkiaShaderType; 343} 344 345void SkiaShader::apply(Caches& caches, const SkiaShaderData& data, 346 const GLsizei width, const GLsizei height) { 347 if (!data.skiaShaderType) return; 348 349 if (data.skiaShaderType & kGradient_SkiaShaderType) { 350 applyGradient(caches, data.gradientData, width, height); 351 } 352 if (data.skiaShaderType & kBitmap_SkiaShaderType) { 353 applyBitmap(caches, data.bitmapData); 354 } 355} 356 357}; // namespace uirenderer 358}; // namespace android 359