SkShader.cpp revision ec3ed6a5ebf6f2c406d7bcf94b6bc34fcaeb976e
1 2/* 3 * Copyright 2006 The Android Open Source Project 4 * 5 * Use of this source code is governed by a BSD-style license that can be 6 * found in the LICENSE file. 7 */ 8 9 10#include "SkScalar.h" 11#include "SkShader.h" 12#include "SkPaint.h" 13#include "SkMallocPixelRef.h" 14 15SkShader::SkShader() : fLocalMatrix(NULL) { 16 SkDEBUGCODE(fInSession = false;) 17} 18 19SkShader::SkShader(SkFlattenableReadBuffer& buffer) 20 : INHERITED(buffer), fLocalMatrix(NULL) { 21 if (buffer.readBool()) { 22 SkMatrix matrix; 23 SkReadMatrix(&buffer, &matrix); 24 setLocalMatrix(matrix); 25 } 26 SkDEBUGCODE(fInSession = false;) 27} 28 29SkShader::~SkShader() { 30 SkASSERT(!fInSession); 31 sk_free(fLocalMatrix); 32} 33 34void SkShader::beginSession() { 35 SkASSERT(!fInSession); 36 SkDEBUGCODE(fInSession = true;) 37} 38 39void SkShader::endSession() { 40 SkASSERT(fInSession); 41 SkDEBUGCODE(fInSession = false;) 42} 43 44void SkShader::flatten(SkFlattenableWriteBuffer& buffer) { 45 this->INHERITED::flatten(buffer); 46 buffer.writeBool(fLocalMatrix != NULL); 47 if (fLocalMatrix) { 48 SkWriteMatrix(&buffer, *fLocalMatrix); 49 } 50} 51 52bool SkShader::getLocalMatrix(SkMatrix* localM) const { 53 if (fLocalMatrix) { 54 if (localM) { 55 *localM = *fLocalMatrix; 56 } 57 return true; 58 } else { 59 if (localM) { 60 localM->reset(); 61 } 62 return false; 63 } 64} 65 66void SkShader::setLocalMatrix(const SkMatrix& localM) { 67 if (localM.isIdentity()) { 68 this->resetLocalMatrix(); 69 } else { 70 if (fLocalMatrix == NULL) { 71 fLocalMatrix = (SkMatrix*)sk_malloc_throw(sizeof(SkMatrix)); 72 } 73 *fLocalMatrix = localM; 74 } 75} 76 77void SkShader::resetLocalMatrix() { 78 if (fLocalMatrix) { 79 sk_free(fLocalMatrix); 80 fLocalMatrix = NULL; 81 } 82} 83 84bool SkShader::setContext(const SkBitmap& device, 85 const SkPaint& paint, 86 const SkMatrix& matrix) { 87 const SkMatrix* m = &matrix; 88 SkMatrix total; 89 90 fDeviceConfig = SkToU8(device.getConfig()); 91 fPaintAlpha = paint.getAlpha(); 92 if (fLocalMatrix) { 93 total.setConcat(matrix, *fLocalMatrix); 94 m = &total; 95 } 96 if (m->invert(&fTotalInverse)) { 97 fTotalInverseClass = (uint8_t)ComputeMatrixClass(fTotalInverse); 98 return true; 99 } 100 return false; 101} 102 103#include "SkColorPriv.h" 104 105void SkShader::shadeSpan16(int x, int y, uint16_t span16[], int count) { 106 SkASSERT(span16); 107 SkASSERT(count > 0); 108 SkASSERT(this->canCallShadeSpan16()); 109 110 // basically, if we get here, the subclass screwed up 111 SkASSERT(!"kHasSpan16 flag is set, but shadeSpan16() not implemented"); 112} 113 114#define kTempColorQuadCount 6 // balance between speed (larger) and saving stack-space 115#define kTempColorCount (kTempColorQuadCount << 2) 116 117#ifdef SK_CPU_BENDIAN 118 #define SkU32BitShiftToByteOffset(shift) (3 - ((shift) >> 3)) 119#else 120 #define SkU32BitShiftToByteOffset(shift) ((shift) >> 3) 121#endif 122 123void SkShader::shadeSpanAlpha(int x, int y, uint8_t alpha[], int count) { 124 SkASSERT(count > 0); 125 126 SkPMColor colors[kTempColorCount]; 127 128 while ((count -= kTempColorCount) >= 0) { 129 this->shadeSpan(x, y, colors, kTempColorCount); 130 x += kTempColorCount; 131 132 const uint8_t* srcA = (const uint8_t*)colors + SkU32BitShiftToByteOffset(SK_A32_SHIFT); 133 int quads = kTempColorQuadCount; 134 do { 135 U8CPU a0 = srcA[0]; 136 U8CPU a1 = srcA[4]; 137 U8CPU a2 = srcA[8]; 138 U8CPU a3 = srcA[12]; 139 srcA += 4*4; 140 *alpha++ = SkToU8(a0); 141 *alpha++ = SkToU8(a1); 142 *alpha++ = SkToU8(a2); 143 *alpha++ = SkToU8(a3); 144 } while (--quads != 0); 145 } 146 SkASSERT(count < 0); 147 SkASSERT(count + kTempColorCount >= 0); 148 if (count += kTempColorCount) { 149 this->shadeSpan(x, y, colors, count); 150 151 const uint8_t* srcA = (const uint8_t*)colors + SkU32BitShiftToByteOffset(SK_A32_SHIFT); 152 do { 153 *alpha++ = *srcA; 154 srcA += 4; 155 } while (--count != 0); 156 } 157#if 0 158 do { 159 int n = count; 160 if (n > kTempColorCount) 161 n = kTempColorCount; 162 SkASSERT(n > 0); 163 164 this->shadeSpan(x, y, colors, n); 165 x += n; 166 count -= n; 167 168 const uint8_t* srcA = (const uint8_t*)colors + SkU32BitShiftToByteOffset(SK_A32_SHIFT); 169 do { 170 *alpha++ = *srcA; 171 srcA += 4; 172 } while (--n != 0); 173 } while (count > 0); 174#endif 175} 176 177SkShader::MatrixClass SkShader::ComputeMatrixClass(const SkMatrix& mat) { 178 MatrixClass mc = kLinear_MatrixClass; 179 180 if (mat.hasPerspective()) { 181 if (mat.fixedStepInX(0, NULL, NULL)) { 182 mc = kFixedStepInX_MatrixClass; 183 } else { 184 mc = kPerspective_MatrixClass; 185 } 186 } 187 return mc; 188} 189 190////////////////////////////////////////////////////////////////////////////// 191 192SkShader::BitmapType SkShader::asABitmap(SkBitmap*, SkMatrix*, 193 TileMode*, SkScalar*) const { 194 return kNone_BitmapType; 195} 196 197SkShader::GradientType SkShader::asAGradient(GradientInfo* info) const { 198 return kNone_GradientType; 199} 200 201SkShader* SkShader::CreateBitmapShader(const SkBitmap& src, 202 TileMode tmx, TileMode tmy) { 203 return SkShader::CreateBitmapShader(src, tmx, tmy, NULL, 0); 204} 205 206////////////////////////////////////////////////////////////////////////////// 207 208#include "SkColorShader.h" 209#include "SkUtils.h" 210 211SkColorShader::SkColorShader() { 212 fFlags = 0; 213 fInheritColor = true; 214} 215 216SkColorShader::SkColorShader(SkColor c) { 217 fFlags = 0; 218 fColor = c; 219 fInheritColor = false; 220} 221 222SkColorShader::~SkColorShader() {} 223 224SkColorShader::SkColorShader(SkFlattenableReadBuffer& b) : INHERITED(b) { 225 fFlags = 0; // computed in setContext 226 227 fInheritColor = b.readU8(); 228 if (fInheritColor) { 229 return; 230 } 231 fColor = b.readU32(); 232} 233 234void SkColorShader::flatten(SkFlattenableWriteBuffer& buffer) { 235 this->INHERITED::flatten(buffer); 236 buffer.write8(fInheritColor); 237 if (fInheritColor) { 238 return; 239 } 240 buffer.write32(fColor); 241} 242 243uint8_t SkColorShader::getSpan16Alpha() const { 244 return SkGetPackedA32(fPMColor); 245} 246 247bool SkColorShader::setContext(const SkBitmap& device, const SkPaint& paint, 248 const SkMatrix& matrix) { 249 if (!this->INHERITED::setContext(device, paint, matrix)) { 250 return false; 251 } 252 253 unsigned a; 254 255 if (fInheritColor) { 256 fColor = paint.getColor(); 257 a = SkColorGetA(fColor); 258 } else { 259 a = SkAlphaMul(SkColorGetA(fColor), SkAlpha255To256(paint.getAlpha())); 260 } 261 262 unsigned r = SkColorGetR(fColor); 263 unsigned g = SkColorGetG(fColor); 264 unsigned b = SkColorGetB(fColor); 265 266 // we want this before we apply any alpha 267 fColor16 = SkPack888ToRGB16(r, g, b); 268 269 if (a != 255) { 270 r = SkMulDiv255Round(r, a); 271 g = SkMulDiv255Round(g, a); 272 b = SkMulDiv255Round(b, a); 273 } 274 fPMColor = SkPackARGB32(a, r, g, b); 275 276 fFlags = kConstInY32_Flag; 277 if (255 == a) { 278 fFlags |= kOpaqueAlpha_Flag; 279 if (paint.isDither() == false) { 280 fFlags |= kHasSpan16_Flag; 281 } 282 } 283 284 return true; 285} 286 287void SkColorShader::shadeSpan(int x, int y, SkPMColor span[], int count) { 288 sk_memset32(span, fPMColor, count); 289} 290 291void SkColorShader::shadeSpan16(int x, int y, uint16_t span[], int count) { 292 sk_memset16(span, fColor16, count); 293} 294 295void SkColorShader::shadeSpanAlpha(int x, int y, uint8_t alpha[], int count) { 296 memset(alpha, SkGetPackedA32(fPMColor), count); 297} 298 299// if we had a asAColor method, that would be more efficient... 300SkShader::BitmapType SkColorShader::asABitmap(SkBitmap* bitmap, SkMatrix* matrix, 301 TileMode modes[], 302 SkScalar* twoPointRadialParams) const { 303 return kNone_BitmapType; 304} 305 306SkShader::GradientType SkColorShader::asAGradient(GradientInfo* info) const { 307 if (info) { 308 if (info->fColors && info->fColorCount >= 1) { 309 info->fColors[0] = fColor; 310 } 311 info->fColorCount = 1; 312 info->fTileMode = SkShader::kRepeat_TileMode; 313 } 314 return kColor_GradientType; 315} 316 317/////////////////////////////////////////////////////////////////////////////// 318 319#include "SkEmptyShader.h" 320 321SkEmptyShader::SkEmptyShader() {} 322SkEmptyShader::SkEmptyShader(SkFlattenableReadBuffer& b) : INHERITED(b) {} 323 324uint32_t SkEmptyShader::getFlags() { return 0; } 325uint8_t SkEmptyShader::getSpan16Alpha() const { return 0; } 326bool SkEmptyShader::setContext(const SkBitmap& device, const SkPaint& paint, 327 const SkMatrix& matrix) { 328 return false; 329} 330void SkEmptyShader::shadeSpan(int x, int y, SkPMColor span[], int count) {} 331void SkEmptyShader::shadeSpan16(int x, int y, uint16_t span[], int count) {} 332void SkEmptyShader::shadeSpanAlpha(int x, int y, uint8_t alpha[], int count) {} 333 334SkFlattenable::Factory SkEmptyShader::getFactory() { return NULL; } 335void SkEmptyShader::flatten(SkFlattenableWriteBuffer& buffer) { 336 this->INHERITED::flatten(buffer); 337} 338 339