SkGradientShader.cpp revision dd9ea9262cb61b545fcf414fbde677eb2b62fee4
1/* 2 * Copyright 2006 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 "SkGradientShaderPriv.h" 9#include "SkLinearGradient.h" 10#include "SkRadialGradient.h" 11#include "SkTwoPointRadialGradient.h" 12#include "SkTwoPointConicalGradient.h" 13#include "SkSweepGradient.h" 14 15SkGradientShaderBase::SkGradientShaderBase(const Descriptor& desc) { 16 SkASSERT(desc.fCount > 1); 17 18 fCacheAlpha = 256; // init to a value that paint.getAlpha() can't return 19 20 fMapper = desc.fMapper; 21 SkSafeRef(fMapper); 22 fGradFlags = SkToU8(desc.fFlags); 23 24 SkASSERT((unsigned)desc.fTileMode < SkShader::kTileModeCount); 25 SkASSERT(SkShader::kTileModeCount == SK_ARRAY_COUNT(gTileProcs)); 26 fTileMode = desc.fTileMode; 27 fTileProc = gTileProcs[desc.fTileMode]; 28 29 fCache16 = fCache16Storage = NULL; 30 fCache32 = NULL; 31 fCache32PixelRef = NULL; 32 33 /* Note: we let the caller skip the first and/or last position. 34 i.e. pos[0] = 0.3, pos[1] = 0.7 35 In these cases, we insert dummy entries to ensure that the final data 36 will be bracketed by [0, 1]. 37 i.e. our_pos[0] = 0, our_pos[1] = 0.3, our_pos[2] = 0.7, our_pos[3] = 1 38 39 Thus colorCount (the caller's value, and fColorCount (our value) may 40 differ by up to 2. In the above example: 41 colorCount = 2 42 fColorCount = 4 43 */ 44 fColorCount = desc.fCount; 45 // check if we need to add in dummy start and/or end position/colors 46 bool dummyFirst = false; 47 bool dummyLast = false; 48 if (desc.fPos) { 49 dummyFirst = desc.fPos[0] != 0; 50 dummyLast = desc.fPos[desc.fCount - 1] != SK_Scalar1; 51 fColorCount += dummyFirst + dummyLast; 52 } 53 54 if (fColorCount > kColorStorageCount) { 55 size_t size = sizeof(SkColor) + sizeof(Rec); 56 fOrigColors = reinterpret_cast<SkColor*>( 57 sk_malloc_throw(size * fColorCount)); 58 } 59 else { 60 fOrigColors = fStorage; 61 } 62 63 // Now copy over the colors, adding the dummies as needed 64 { 65 SkColor* origColors = fOrigColors; 66 if (dummyFirst) { 67 *origColors++ = desc.fColors[0]; 68 } 69 memcpy(origColors, desc.fColors, desc.fCount * sizeof(SkColor)); 70 if (dummyLast) { 71 origColors += desc.fCount; 72 *origColors = desc.fColors[desc.fCount - 1]; 73 } 74 } 75 76 fRecs = (Rec*)(fOrigColors + fColorCount); 77 if (fColorCount > 2) { 78 Rec* recs = fRecs; 79 recs->fPos = 0; 80 // recs->fScale = 0; // unused; 81 recs += 1; 82 if (desc.fPos) { 83 /* We need to convert the user's array of relative positions into 84 fixed-point positions and scale factors. We need these results 85 to be strictly monotonic (no two values equal or out of order). 86 Hence this complex loop that just jams a zero for the scale 87 value if it sees a segment out of order, and it assures that 88 we start at 0 and end at 1.0 89 */ 90 SkFixed prev = 0; 91 int startIndex = dummyFirst ? 0 : 1; 92 int count = desc.fCount + dummyLast; 93 for (int i = startIndex; i < count; i++) { 94 // force the last value to be 1.0 95 SkFixed curr; 96 if (i == desc.fCount) { // we're really at the dummyLast 97 curr = SK_Fixed1; 98 } else { 99 curr = SkScalarToFixed(desc.fPos[i]); 100 } 101 // pin curr withing range 102 if (curr < 0) { 103 curr = 0; 104 } else if (curr > SK_Fixed1) { 105 curr = SK_Fixed1; 106 } 107 recs->fPos = curr; 108 if (curr > prev) { 109 recs->fScale = (1 << 24) / (curr - prev); 110 } else { 111 recs->fScale = 0; // ignore this segment 112 } 113 // get ready for the next value 114 prev = curr; 115 recs += 1; 116 } 117 } else { // assume even distribution 118 SkFixed dp = SK_Fixed1 / (desc.fCount - 1); 119 SkFixed p = dp; 120 SkFixed scale = (desc.fCount - 1) << 8; // (1 << 24) / dp 121 for (int i = 1; i < desc.fCount; i++) { 122 recs->fPos = p; 123 recs->fScale = scale; 124 recs += 1; 125 p += dp; 126 } 127 } 128 } 129 this->initCommon(); 130} 131 132static uint32_t pack_mode_flags(SkShader::TileMode mode, uint32_t flags) { 133 SkASSERT(0 == (flags >> 28)); 134 SkASSERT(0 == ((uint32_t)mode >> 4)); 135 return (flags << 4) | mode; 136} 137 138static SkShader::TileMode unpack_mode(uint32_t packed) { 139 return (SkShader::TileMode)(packed & 0xF); 140} 141 142static uint32_t unpack_flags(uint32_t packed) { 143 return packed >> 4; 144} 145 146SkGradientShaderBase::SkGradientShaderBase(SkFlattenableReadBuffer& buffer) : INHERITED(buffer) { 147 fCacheAlpha = 256; 148 149 fMapper = buffer.readUnitMapper(); 150 151 fCache16 = fCache16Storage = NULL; 152 fCache32 = NULL; 153 fCache32PixelRef = NULL; 154 155 int colorCount = fColorCount = buffer.getArrayCount(); 156 if (colorCount > kColorStorageCount) { 157 size_t allocSize = (sizeof(SkColor) + sizeof(SkPMColor) + sizeof(Rec)) * colorCount; 158 if (buffer.validateAvailable(allocSize)) { 159 fOrigColors = reinterpret_cast<SkColor*>(sk_malloc_throw(allocSize)); 160 } else { 161 fOrigColors = NULL; 162 colorCount = fColorCount = 0; 163 } 164 } else { 165 fOrigColors = fStorage; 166 } 167 buffer.readColorArray(fOrigColors, colorCount); 168 169 { 170 uint32_t packed = buffer.readUInt(); 171 fGradFlags = SkToU8(unpack_flags(packed)); 172 fTileMode = unpack_mode(packed); 173 } 174 fTileProc = gTileProcs[fTileMode]; 175 fRecs = (Rec*)(fOrigColors + colorCount); 176 if (colorCount > 2) { 177 Rec* recs = fRecs; 178 recs[0].fPos = 0; 179 for (int i = 1; i < colorCount; i++) { 180 recs[i].fPos = buffer.readInt(); 181 recs[i].fScale = buffer.readUInt(); 182 } 183 } 184 buffer.readMatrix(&fPtsToUnit); 185 this->initCommon(); 186} 187 188SkGradientShaderBase::~SkGradientShaderBase() { 189 if (fCache16Storage) { 190 sk_free(fCache16Storage); 191 } 192 SkSafeUnref(fCache32PixelRef); 193 if (fOrigColors != fStorage) { 194 sk_free(fOrigColors); 195 } 196 SkSafeUnref(fMapper); 197} 198 199void SkGradientShaderBase::initCommon() { 200 fFlags = 0; 201 unsigned colorAlpha = 0xFF; 202 for (int i = 0; i < fColorCount; i++) { 203 colorAlpha &= SkColorGetA(fOrigColors[i]); 204 } 205 fColorsAreOpaque = colorAlpha == 0xFF; 206} 207 208void SkGradientShaderBase::flatten(SkFlattenableWriteBuffer& buffer) const { 209 this->INHERITED::flatten(buffer); 210 buffer.writeFlattenable(fMapper); 211 buffer.writeColorArray(fOrigColors, fColorCount); 212 buffer.writeUInt(pack_mode_flags(fTileMode, fGradFlags)); 213 if (fColorCount > 2) { 214 Rec* recs = fRecs; 215 for (int i = 1; i < fColorCount; i++) { 216 buffer.writeInt(recs[i].fPos); 217 buffer.writeUInt(recs[i].fScale); 218 } 219 } 220 buffer.writeMatrix(fPtsToUnit); 221} 222 223bool SkGradientShaderBase::isOpaque() const { 224 return fColorsAreOpaque; 225} 226 227bool SkGradientShaderBase::setContext(const SkBitmap& device, 228 const SkPaint& paint, 229 const SkMatrix& matrix) { 230 if (!this->INHERITED::setContext(device, paint, matrix)) { 231 return false; 232 } 233 234 const SkMatrix& inverse = this->getTotalInverse(); 235 236 if (!fDstToIndex.setConcat(fPtsToUnit, inverse)) { 237 // need to keep our set/end context calls balanced. 238 this->INHERITED::endContext(); 239 return false; 240 } 241 242 fDstToIndexProc = fDstToIndex.getMapXYProc(); 243 fDstToIndexClass = (uint8_t)SkShader::ComputeMatrixClass(fDstToIndex); 244 245 // now convert our colors in to PMColors 246 unsigned paintAlpha = this->getPaintAlpha(); 247 248 fFlags = this->INHERITED::getFlags(); 249 if (fColorsAreOpaque && paintAlpha == 0xFF) { 250 fFlags |= kOpaqueAlpha_Flag; 251 } 252 // we can do span16 as long as our individual colors are opaque, 253 // regardless of the paint's alpha 254 if (fColorsAreOpaque) { 255 fFlags |= kHasSpan16_Flag; 256 } 257 258 this->setCacheAlpha(paintAlpha); 259 return true; 260} 261 262void SkGradientShaderBase::setCacheAlpha(U8CPU alpha) const { 263 // if the new alpha differs from the previous time we were called, inval our cache 264 // this will trigger the cache to be rebuilt. 265 // we don't care about the first time, since the cache ptrs will already be NULL 266 if (fCacheAlpha != alpha) { 267 fCache16 = NULL; // inval the cache 268 fCache32 = NULL; // inval the cache 269 fCacheAlpha = alpha; // record the new alpha 270 // inform our subclasses 271 if (fCache32PixelRef) { 272 fCache32PixelRef->notifyPixelsChanged(); 273 } 274 } 275} 276 277#define Fixed_To_Dot8(x) (((x) + 0x80) >> 8) 278 279/** We take the original colors, not our premultiplied PMColors, since we can 280 build a 16bit table as long as the original colors are opaque, even if the 281 paint specifies a non-opaque alpha. 282*/ 283void SkGradientShaderBase::Build16bitCache(uint16_t cache[], SkColor c0, SkColor c1, 284 int count) { 285 SkASSERT(count > 1); 286 SkASSERT(SkColorGetA(c0) == 0xFF); 287 SkASSERT(SkColorGetA(c1) == 0xFF); 288 289 SkFixed r = SkColorGetR(c0); 290 SkFixed g = SkColorGetG(c0); 291 SkFixed b = SkColorGetB(c0); 292 293 SkFixed dr = SkIntToFixed(SkColorGetR(c1) - r) / (count - 1); 294 SkFixed dg = SkIntToFixed(SkColorGetG(c1) - g) / (count - 1); 295 SkFixed db = SkIntToFixed(SkColorGetB(c1) - b) / (count - 1); 296 297 r = SkIntToFixed(r) + 0x8000; 298 g = SkIntToFixed(g) + 0x8000; 299 b = SkIntToFixed(b) + 0x8000; 300 301 do { 302 unsigned rr = r >> 16; 303 unsigned gg = g >> 16; 304 unsigned bb = b >> 16; 305 cache[0] = SkPackRGB16(SkR32ToR16(rr), SkG32ToG16(gg), SkB32ToB16(bb)); 306 cache[kCache16Count] = SkDitherPack888ToRGB16(rr, gg, bb); 307 cache += 1; 308 r += dr; 309 g += dg; 310 b += db; 311 } while (--count != 0); 312} 313 314/* 315 * r,g,b used to be SkFixed, but on gcc (4.2.1 mac and 4.6.3 goobuntu) in 316 * release builds, we saw a compiler error where the 0xFF parameter in 317 * SkPackARGB32() was being totally ignored whenever it was called with 318 * a non-zero add (e.g. 0x8000). 319 * 320 * We found two work-arounds: 321 * 1. change r,g,b to unsigned (or just one of them) 322 * 2. change SkPackARGB32 to + its (a << SK_A32_SHIFT) value instead 323 * of using | 324 * 325 * We chose #1 just because it was more localized. 326 * See http://code.google.com/p/skia/issues/detail?id=1113 327 * 328 * The type SkUFixed encapsulate this need for unsigned, but logically Fixed. 329 */ 330typedef uint32_t SkUFixed; 331 332void SkGradientShaderBase::Build32bitCache(SkPMColor cache[], SkColor c0, SkColor c1, 333 int count, U8CPU paintAlpha, uint32_t gradFlags) { 334 SkASSERT(count > 1); 335 336 // need to apply paintAlpha to our two endpoints 337 uint32_t a0 = SkMulDiv255Round(SkColorGetA(c0), paintAlpha); 338 uint32_t a1 = SkMulDiv255Round(SkColorGetA(c1), paintAlpha); 339 340 341 const bool interpInPremul = SkToBool(gradFlags & 342 SkGradientShader::kInterpolateColorsInPremul_Flag); 343 344 uint32_t r0 = SkColorGetR(c0); 345 uint32_t g0 = SkColorGetG(c0); 346 uint32_t b0 = SkColorGetB(c0); 347 348 uint32_t r1 = SkColorGetR(c1); 349 uint32_t g1 = SkColorGetG(c1); 350 uint32_t b1 = SkColorGetB(c1); 351 352 if (interpInPremul) { 353 r0 = SkMulDiv255Round(r0, a0); 354 g0 = SkMulDiv255Round(g0, a0); 355 b0 = SkMulDiv255Round(b0, a0); 356 357 r1 = SkMulDiv255Round(r1, a1); 358 g1 = SkMulDiv255Round(g1, a1); 359 b1 = SkMulDiv255Round(b1, a1); 360 } 361 362 SkFixed da = SkIntToFixed(a1 - a0) / (count - 1); 363 SkFixed dr = SkIntToFixed(r1 - r0) / (count - 1); 364 SkFixed dg = SkIntToFixed(g1 - g0) / (count - 1); 365 SkFixed db = SkIntToFixed(b1 - b0) / (count - 1); 366 367 /* We pre-add 1/8 to avoid having to add this to our [0] value each time 368 in the loop. Without this, the bias for each would be 369 0x2000 0xA000 0xE000 0x6000 370 With this trick, we can add 0 for the first (no-op) and just adjust the 371 others. 372 */ 373 SkUFixed a = SkIntToFixed(a0) + 0x2000; 374 SkUFixed r = SkIntToFixed(r0) + 0x2000; 375 SkUFixed g = SkIntToFixed(g0) + 0x2000; 376 SkUFixed b = SkIntToFixed(b0) + 0x2000; 377 378 /* 379 * Our dither-cell (spatially) is 380 * 0 2 381 * 3 1 382 * Where 383 * [0] -> [-1/8 ... 1/8 ) values near 0 384 * [1] -> [ 1/8 ... 3/8 ) values near 1/4 385 * [2] -> [ 3/8 ... 5/8 ) values near 1/2 386 * [3] -> [ 5/8 ... 7/8 ) values near 3/4 387 */ 388 389 if (0xFF == a0 && 0 == da) { 390 do { 391 cache[kCache32Count*0] = SkPackARGB32(0xFF, (r + 0 ) >> 16, 392 (g + 0 ) >> 16, 393 (b + 0 ) >> 16); 394 cache[kCache32Count*1] = SkPackARGB32(0xFF, (r + 0x8000) >> 16, 395 (g + 0x8000) >> 16, 396 (b + 0x8000) >> 16); 397 cache[kCache32Count*2] = SkPackARGB32(0xFF, (r + 0xC000) >> 16, 398 (g + 0xC000) >> 16, 399 (b + 0xC000) >> 16); 400 cache[kCache32Count*3] = SkPackARGB32(0xFF, (r + 0x4000) >> 16, 401 (g + 0x4000) >> 16, 402 (b + 0x4000) >> 16); 403 cache += 1; 404 r += dr; 405 g += dg; 406 b += db; 407 } while (--count != 0); 408 } else if (interpInPremul) { 409 do { 410 cache[kCache32Count*0] = SkPackARGB32((a + 0 ) >> 16, 411 (r + 0 ) >> 16, 412 (g + 0 ) >> 16, 413 (b + 0 ) >> 16); 414 cache[kCache32Count*1] = SkPackARGB32((a + 0x8000) >> 16, 415 (r + 0x8000) >> 16, 416 (g + 0x8000) >> 16, 417 (b + 0x8000) >> 16); 418 cache[kCache32Count*2] = SkPackARGB32((a + 0xC000) >> 16, 419 (r + 0xC000) >> 16, 420 (g + 0xC000) >> 16, 421 (b + 0xC000) >> 16); 422 cache[kCache32Count*3] = SkPackARGB32((a + 0x4000) >> 16, 423 (r + 0x4000) >> 16, 424 (g + 0x4000) >> 16, 425 (b + 0x4000) >> 16); 426 cache += 1; 427 a += da; 428 r += dr; 429 g += dg; 430 b += db; 431 } while (--count != 0); 432 } else { // interpolate in unpreml space 433 do { 434 cache[kCache32Count*0] = SkPremultiplyARGBInline((a + 0 ) >> 16, 435 (r + 0 ) >> 16, 436 (g + 0 ) >> 16, 437 (b + 0 ) >> 16); 438 cache[kCache32Count*1] = SkPremultiplyARGBInline((a + 0x8000) >> 16, 439 (r + 0x8000) >> 16, 440 (g + 0x8000) >> 16, 441 (b + 0x8000) >> 16); 442 cache[kCache32Count*2] = SkPremultiplyARGBInline((a + 0xC000) >> 16, 443 (r + 0xC000) >> 16, 444 (g + 0xC000) >> 16, 445 (b + 0xC000) >> 16); 446 cache[kCache32Count*3] = SkPremultiplyARGBInline((a + 0x4000) >> 16, 447 (r + 0x4000) >> 16, 448 (g + 0x4000) >> 16, 449 (b + 0x4000) >> 16); 450 cache += 1; 451 a += da; 452 r += dr; 453 g += dg; 454 b += db; 455 } while (--count != 0); 456 } 457} 458 459static inline int SkFixedToFFFF(SkFixed x) { 460 SkASSERT((unsigned)x <= SK_Fixed1); 461 return x - (x >> 16); 462} 463 464static inline U16CPU bitsTo16(unsigned x, const unsigned bits) { 465 SkASSERT(x < (1U << bits)); 466 if (6 == bits) { 467 return (x << 10) | (x << 4) | (x >> 2); 468 } 469 if (8 == bits) { 470 return (x << 8) | x; 471 } 472 sk_throw(); 473 return 0; 474} 475 476const uint16_t* SkGradientShaderBase::getCache16() const { 477 if (fCache16 == NULL) { 478 // double the count for dither entries 479 const int entryCount = kCache16Count * 2; 480 const size_t allocSize = sizeof(uint16_t) * entryCount; 481 482 if (fCache16Storage == NULL) { // set the storage and our working ptr 483 fCache16Storage = (uint16_t*)sk_malloc_throw(allocSize); 484 } 485 fCache16 = fCache16Storage; 486 if (fColorCount == 2) { 487 Build16bitCache(fCache16, fOrigColors[0], fOrigColors[1], 488 kCache16Count); 489 } else { 490 Rec* rec = fRecs; 491 int prevIndex = 0; 492 for (int i = 1; i < fColorCount; i++) { 493 int nextIndex = SkFixedToFFFF(rec[i].fPos) >> kCache16Shift; 494 SkASSERT(nextIndex < kCache16Count); 495 496 if (nextIndex > prevIndex) 497 Build16bitCache(fCache16 + prevIndex, fOrigColors[i-1], fOrigColors[i], nextIndex - prevIndex + 1); 498 prevIndex = nextIndex; 499 } 500 } 501 502 if (fMapper) { 503 fCache16Storage = (uint16_t*)sk_malloc_throw(allocSize); 504 uint16_t* linear = fCache16; // just computed linear data 505 uint16_t* mapped = fCache16Storage; // storage for mapped data 506 SkUnitMapper* map = fMapper; 507 for (int i = 0; i < kCache16Count; i++) { 508 int index = map->mapUnit16(bitsTo16(i, kCache16Bits)) >> kCache16Shift; 509 mapped[i] = linear[index]; 510 mapped[i + kCache16Count] = linear[index + kCache16Count]; 511 } 512 sk_free(fCache16); 513 fCache16 = fCache16Storage; 514 } 515 } 516 return fCache16; 517} 518 519const SkPMColor* SkGradientShaderBase::getCache32() const { 520 if (fCache32 == NULL) { 521 SkImageInfo info; 522 info.fWidth = kCache32Count; 523 info.fHeight = 4; // for our 4 dither rows 524 info.fAlphaType = kPremul_SkAlphaType; 525 info.fColorType = kPMColor_SkColorType; 526 527 if (NULL == fCache32PixelRef) { 528 fCache32PixelRef = SkMallocPixelRef::NewAllocate(info, 0, NULL); 529 } 530 fCache32 = (SkPMColor*)fCache32PixelRef->getAddr(); 531 if (fColorCount == 2) { 532 Build32bitCache(fCache32, fOrigColors[0], fOrigColors[1], 533 kCache32Count, fCacheAlpha, fGradFlags); 534 } else { 535 Rec* rec = fRecs; 536 int prevIndex = 0; 537 for (int i = 1; i < fColorCount; i++) { 538 int nextIndex = SkFixedToFFFF(rec[i].fPos) >> kCache32Shift; 539 SkASSERT(nextIndex < kCache32Count); 540 541 if (nextIndex > prevIndex) 542 Build32bitCache(fCache32 + prevIndex, fOrigColors[i-1], 543 fOrigColors[i], nextIndex - prevIndex + 1, 544 fCacheAlpha, fGradFlags); 545 prevIndex = nextIndex; 546 } 547 } 548 549 if (fMapper) { 550 SkMallocPixelRef* newPR = SkMallocPixelRef::NewAllocate(info, 0, NULL); 551 SkPMColor* linear = fCache32; // just computed linear data 552 SkPMColor* mapped = (SkPMColor*)newPR->getAddr(); // storage for mapped data 553 SkUnitMapper* map = fMapper; 554 for (int i = 0; i < kCache32Count; i++) { 555 int index = map->mapUnit16((i << 8) | i) >> 8; 556 mapped[i + kCache32Count*0] = linear[index + kCache32Count*0]; 557 mapped[i + kCache32Count*1] = linear[index + kCache32Count*1]; 558 mapped[i + kCache32Count*2] = linear[index + kCache32Count*2]; 559 mapped[i + kCache32Count*3] = linear[index + kCache32Count*3]; 560 } 561 fCache32PixelRef->unref(); 562 fCache32PixelRef = newPR; 563 fCache32 = (SkPMColor*)newPR->getAddr(); 564 } 565 } 566 return fCache32; 567} 568 569/* 570 * Because our caller might rebuild the same (logically the same) gradient 571 * over and over, we'd like to return exactly the same "bitmap" if possible, 572 * allowing the client to utilize a cache of our bitmap (e.g. with a GPU). 573 * To do that, we maintain a private cache of built-bitmaps, based on our 574 * colors and positions. Note: we don't try to flatten the fMapper, so if one 575 * is present, we skip the cache for now. 576 */ 577void SkGradientShaderBase::getGradientTableBitmap(SkBitmap* bitmap) const { 578 // our caller assumes no external alpha, so we ensure that our cache is 579 // built with 0xFF 580 this->setCacheAlpha(0xFF); 581 582 // don't have a way to put the mapper into our cache-key yet 583 if (fMapper) { 584 // force our cahce32pixelref to be built 585 (void)this->getCache32(); 586 bitmap->installPixelRef(fCache32PixelRef); 587 return; 588 } 589 590 // build our key: [numColors + colors[] + {positions[]} + flags ] 591 int count = 1 + fColorCount + 1; 592 if (fColorCount > 2) { 593 count += fColorCount - 1; // fRecs[].fPos 594 } 595 596 SkAutoSTMalloc<16, int32_t> storage(count); 597 int32_t* buffer = storage.get(); 598 599 *buffer++ = fColorCount; 600 memcpy(buffer, fOrigColors, fColorCount * sizeof(SkColor)); 601 buffer += fColorCount; 602 if (fColorCount > 2) { 603 for (int i = 1; i < fColorCount; i++) { 604 *buffer++ = fRecs[i].fPos; 605 } 606 } 607 *buffer++ = fGradFlags; 608 SkASSERT(buffer - storage.get() == count); 609 610 /////////////////////////////////// 611 612 SK_DECLARE_STATIC_MUTEX(gMutex); 613 static SkBitmapCache* gCache; 614 // each cache cost 1K of RAM, since each bitmap will be 1x256 at 32bpp 615 static const int MAX_NUM_CACHED_GRADIENT_BITMAPS = 32; 616 SkAutoMutexAcquire ama(gMutex); 617 618 if (NULL == gCache) { 619 gCache = SkNEW_ARGS(SkBitmapCache, (MAX_NUM_CACHED_GRADIENT_BITMAPS)); 620 } 621 size_t size = count * sizeof(int32_t); 622 623 if (!gCache->find(storage.get(), size, bitmap)) { 624 // force our cahce32pixelref to be built 625 (void)this->getCache32(); 626 bitmap->installPixelRef(fCache32PixelRef); 627 628 gCache->add(storage.get(), size, *bitmap); 629 } 630} 631 632void SkGradientShaderBase::commonAsAGradient(GradientInfo* info) const { 633 if (info) { 634 if (info->fColorCount >= fColorCount) { 635 if (info->fColors) { 636 memcpy(info->fColors, fOrigColors, fColorCount * sizeof(SkColor)); 637 } 638 if (info->fColorOffsets) { 639 if (fColorCount == 2) { 640 info->fColorOffsets[0] = 0; 641 info->fColorOffsets[1] = SK_Scalar1; 642 } else if (fColorCount > 2) { 643 for (int i = 0; i < fColorCount; ++i) { 644 info->fColorOffsets[i] = SkFixedToScalar(fRecs[i].fPos); 645 } 646 } 647 } 648 } 649 info->fColorCount = fColorCount; 650 info->fTileMode = fTileMode; 651 info->fGradientFlags = fGradFlags; 652 } 653} 654 655#ifdef SK_DEVELOPER 656void SkGradientShaderBase::toString(SkString* str) const { 657 658 str->appendf("%d colors: ", fColorCount); 659 660 for (int i = 0; i < fColorCount; ++i) { 661 str->appendHex(fOrigColors[i]); 662 if (i < fColorCount-1) { 663 str->append(", "); 664 } 665 } 666 667 if (fColorCount > 2) { 668 str->append(" points: ("); 669 for (int i = 0; i < fColorCount; ++i) { 670 str->appendScalar(SkFixedToScalar(fRecs[i].fPos)); 671 if (i < fColorCount-1) { 672 str->append(", "); 673 } 674 } 675 str->append(")"); 676 } 677 678 static const char* gTileModeName[SkShader::kTileModeCount] = { 679 "clamp", "repeat", "mirror" 680 }; 681 682 str->append(" "); 683 str->append(gTileModeName[fTileMode]); 684 685 // TODO: add "fMapper->toString(str);" when SkUnitMapper::toString is added 686 687 this->INHERITED::toString(str); 688} 689#endif 690 691/////////////////////////////////////////////////////////////////////////////// 692/////////////////////////////////////////////////////////////////////////////// 693 694#include "SkEmptyShader.h" 695 696// assumes colors is SkColor* and pos is SkScalar* 697#define EXPAND_1_COLOR(count) \ 698 SkColor tmp[2]; \ 699 do { \ 700 if (1 == count) { \ 701 tmp[0] = tmp[1] = colors[0]; \ 702 colors = tmp; \ 703 pos = NULL; \ 704 count = 2; \ 705 } \ 706 } while (0) 707 708static void desc_init(SkGradientShaderBase::Descriptor* desc, 709 const SkColor colors[], 710 const SkScalar pos[], int colorCount, 711 SkShader::TileMode mode, 712 SkUnitMapper* mapper, uint32_t flags) { 713 desc->fColors = colors; 714 desc->fPos = pos; 715 desc->fCount = colorCount; 716 desc->fTileMode = mode; 717 desc->fMapper = mapper; 718 desc->fFlags = flags; 719} 720 721SkShader* SkGradientShader::CreateLinear(const SkPoint pts[2], 722 const SkColor colors[], 723 const SkScalar pos[], int colorCount, 724 SkShader::TileMode mode, 725 SkUnitMapper* mapper, 726 uint32_t flags) { 727 if (NULL == pts || NULL == colors || colorCount < 1) { 728 return NULL; 729 } 730 EXPAND_1_COLOR(colorCount); 731 732 SkGradientShaderBase::Descriptor desc; 733 desc_init(&desc, colors, pos, colorCount, mode, mapper, flags); 734 return SkNEW_ARGS(SkLinearGradient, (pts, desc)); 735} 736 737SkShader* SkGradientShader::CreateRadial(const SkPoint& center, SkScalar radius, 738 const SkColor colors[], 739 const SkScalar pos[], int colorCount, 740 SkShader::TileMode mode, 741 SkUnitMapper* mapper, 742 uint32_t flags) { 743 if (radius <= 0 || NULL == colors || colorCount < 1) { 744 return NULL; 745 } 746 EXPAND_1_COLOR(colorCount); 747 748 SkGradientShaderBase::Descriptor desc; 749 desc_init(&desc, colors, pos, colorCount, mode, mapper, flags); 750 return SkNEW_ARGS(SkRadialGradient, (center, radius, desc)); 751} 752 753SkShader* SkGradientShader::CreateTwoPointRadial(const SkPoint& start, 754 SkScalar startRadius, 755 const SkPoint& end, 756 SkScalar endRadius, 757 const SkColor colors[], 758 const SkScalar pos[], 759 int colorCount, 760 SkShader::TileMode mode, 761 SkUnitMapper* mapper, 762 uint32_t flags) { 763 if (startRadius < 0 || endRadius < 0 || NULL == colors || colorCount < 1) { 764 return NULL; 765 } 766 EXPAND_1_COLOR(colorCount); 767 768 SkGradientShaderBase::Descriptor desc; 769 desc_init(&desc, colors, pos, colorCount, mode, mapper, flags); 770 return SkNEW_ARGS(SkTwoPointRadialGradient, 771 (start, startRadius, end, endRadius, desc)); 772} 773 774SkShader* SkGradientShader::CreateTwoPointConical(const SkPoint& start, 775 SkScalar startRadius, 776 const SkPoint& end, 777 SkScalar endRadius, 778 const SkColor colors[], 779 const SkScalar pos[], 780 int colorCount, 781 SkShader::TileMode mode, 782 SkUnitMapper* mapper, 783 uint32_t flags) { 784 if (startRadius < 0 || endRadius < 0 || NULL == colors || colorCount < 1) { 785 return NULL; 786 } 787 if (start == end && startRadius == endRadius) { 788 return SkNEW(SkEmptyShader); 789 } 790 EXPAND_1_COLOR(colorCount); 791 792 SkGradientShaderBase::Descriptor desc; 793 desc_init(&desc, colors, pos, colorCount, mode, mapper, flags); 794 return SkNEW_ARGS(SkTwoPointConicalGradient, 795 (start, startRadius, end, endRadius, desc)); 796} 797 798SkShader* SkGradientShader::CreateSweep(SkScalar cx, SkScalar cy, 799 const SkColor colors[], 800 const SkScalar pos[], 801 int colorCount, SkUnitMapper* mapper, 802 uint32_t flags) { 803 if (NULL == colors || colorCount < 1) { 804 return NULL; 805 } 806 EXPAND_1_COLOR(colorCount); 807 808 SkGradientShaderBase::Descriptor desc; 809 desc_init(&desc, colors, pos, colorCount, SkShader::kClamp_TileMode, mapper, flags); 810 return SkNEW_ARGS(SkSweepGradient, (cx, cy, desc)); 811} 812 813SK_DEFINE_FLATTENABLE_REGISTRAR_GROUP_START(SkGradientShader) 814 SK_DEFINE_FLATTENABLE_REGISTRAR_ENTRY(SkLinearGradient) 815 SK_DEFINE_FLATTENABLE_REGISTRAR_ENTRY(SkRadialGradient) 816 SK_DEFINE_FLATTENABLE_REGISTRAR_ENTRY(SkSweepGradient) 817 SK_DEFINE_FLATTENABLE_REGISTRAR_ENTRY(SkTwoPointRadialGradient) 818 SK_DEFINE_FLATTENABLE_REGISTRAR_ENTRY(SkTwoPointConicalGradient) 819SK_DEFINE_FLATTENABLE_REGISTRAR_GROUP_END 820 821/////////////////////////////////////////////////////////////////////////////// 822 823#if SK_SUPPORT_GPU 824 825#include "effects/GrTextureStripAtlas.h" 826#include "GrTBackendEffectFactory.h" 827#include "SkGr.h" 828 829GrGLGradientEffect::GrGLGradientEffect(const GrBackendEffectFactory& factory) 830 : INHERITED(factory) 831 , fCachedYCoord(SK_ScalarMax) { 832} 833 834GrGLGradientEffect::~GrGLGradientEffect() { } 835 836void GrGLGradientEffect::emitUniforms(GrGLShaderBuilder* builder, EffectKey key) { 837 838 if (GrGradientEffect::kTwo_ColorType == ColorTypeFromKey(key)) { // 2 Color case 839 fColorStartUni = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility, 840 kVec4f_GrSLType, "GradientStartColor"); 841 fColorEndUni = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility, 842 kVec4f_GrSLType, "GradientEndColor"); 843 844 } else if (GrGradientEffect::kThree_ColorType == ColorTypeFromKey(key)){ // 3 Color Case 845 fColorStartUni = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility, 846 kVec4f_GrSLType, "GradientStartColor"); 847 fColorMidUni = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility, 848 kVec4f_GrSLType, "GradientMidColor"); 849 fColorEndUni = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility, 850 kVec4f_GrSLType, "GradientEndColor"); 851 852 } else { // if not a fast case 853 fFSYUni = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility, 854 kFloat_GrSLType, "GradientYCoordFS"); 855 } 856} 857 858static inline void set_color_uni(const GrGLUniformManager& uman, 859 const GrGLUniformManager::UniformHandle uni, 860 const SkColor* color) { 861 uman.set4f(uni, 862 SkColorGetR(*color) / 255.f, 863 SkColorGetG(*color) / 255.f, 864 SkColorGetB(*color) / 255.f, 865 SkColorGetA(*color) / 255.f); 866} 867 868static inline void set_mul_color_uni(const GrGLUniformManager& uman, 869 const GrGLUniformManager::UniformHandle uni, 870 const SkColor* color){ 871 float a = SkColorGetA(*color) / 255.f; 872 float aDiv255 = a / 255.f; 873 uman.set4f(uni, 874 SkColorGetR(*color) * aDiv255, 875 SkColorGetG(*color) * aDiv255, 876 SkColorGetB(*color) * aDiv255, 877 a); 878} 879 880void GrGLGradientEffect::setData(const GrGLUniformManager& uman, 881 const GrDrawEffect& drawEffect) { 882 883 const GrGradientEffect& e = drawEffect.castEffect<GrGradientEffect>(); 884 885 886 if (GrGradientEffect::kTwo_ColorType == e.getColorType()){ 887 888 if (GrGradientEffect::kBeforeInterp_PremulType == e.getPremulType()) { 889 set_mul_color_uni(uman, fColorStartUni, e.getColors(0)); 890 set_mul_color_uni(uman, fColorEndUni, e.getColors(1)); 891 } else { 892 set_color_uni(uman, fColorStartUni, e.getColors(0)); 893 set_color_uni(uman, fColorEndUni, e.getColors(1)); 894 } 895 896 } else if (GrGradientEffect::kThree_ColorType == e.getColorType()){ 897 898 if (GrGradientEffect::kBeforeInterp_PremulType == e.getPremulType()) { 899 set_mul_color_uni(uman, fColorStartUni, e.getColors(0)); 900 set_mul_color_uni(uman, fColorMidUni, e.getColors(1)); 901 set_mul_color_uni(uman, fColorEndUni, e.getColors(2)); 902 } else { 903 set_color_uni(uman, fColorStartUni, e.getColors(0)); 904 set_color_uni(uman, fColorMidUni, e.getColors(1)); 905 set_color_uni(uman, fColorEndUni, e.getColors(2)); 906 } 907 } else { 908 909 SkScalar yCoord = e.getYCoord(); 910 if (yCoord != fCachedYCoord) { 911 uman.set1f(fFSYUni, yCoord); 912 fCachedYCoord = yCoord; 913 } 914 } 915} 916 917 918GrGLEffect::EffectKey GrGLGradientEffect::GenBaseGradientKey(const GrDrawEffect& drawEffect) { 919 const GrGradientEffect& e = drawEffect.castEffect<GrGradientEffect>(); 920 921 EffectKey key = 0; 922 923 if (GrGradientEffect::kTwo_ColorType == e.getColorType()) { 924 key |= kTwoColorKey; 925 } else if (GrGradientEffect::kThree_ColorType == e.getColorType()){ 926 key |= kThreeColorKey; 927 } 928 929 if (GrGradientEffect::kBeforeInterp_PremulType == e.getPremulType()) { 930 key |= kPremulBeforeInterpKey; 931 } 932 933 return key; 934} 935 936void GrGLGradientEffect::emitColor(GrGLShaderBuilder* builder, 937 const char* gradientTValue, 938 EffectKey key, 939 const char* outputColor, 940 const char* inputColor, 941 const TextureSamplerArray& samplers) { 942 if (GrGradientEffect::kTwo_ColorType == ColorTypeFromKey(key)){ 943 builder->fsCodeAppendf("\tvec4 colorTemp = mix(%s, %s, clamp(%s, 0.0, 1.0));\n", 944 builder->getUniformVariable(fColorStartUni).c_str(), 945 builder->getUniformVariable(fColorEndUni).c_str(), 946 gradientTValue); 947 // Note that we could skip this step if both colors are known to be opaque. Two 948 // considerations: 949 // The gradient SkShader reporting opaque is more restrictive than necessary in the two pt 950 // case. Make sure the key reflects this optimization (and note that it can use the same 951 // shader as thekBeforeIterp case). This same optimization applies to the 3 color case below. 952 if (GrGradientEffect::kAfterInterp_PremulType == PremulTypeFromKey(key)) { 953 builder->fsCodeAppend("\tcolorTemp.rgb *= colorTemp.a;\n"); 954 } 955 956 builder->fsCodeAppendf("\t%s = %s;\n", outputColor, 957 (GrGLSLExpr4(inputColor) * GrGLSLExpr4("colorTemp")).c_str()); 958 } else if (GrGradientEffect::kThree_ColorType == ColorTypeFromKey(key)){ 959 builder->fsCodeAppendf("\tfloat oneMinus2t = 1.0 - (2.0 * (%s));\n", 960 gradientTValue); 961 builder->fsCodeAppendf("\tvec4 colorTemp = clamp(oneMinus2t, 0.0, 1.0) * %s;\n", 962 builder->getUniformVariable(fColorStartUni).c_str()); 963 if (kTegra3_GrGLRenderer == builder->ctxInfo().renderer()) { 964 // The Tegra3 compiler will sometimes never return if we have 965 // min(abs(oneMinus2t), 1.0), or do the abs first in a separate expression. 966 builder->fsCodeAppend("\tfloat minAbs = abs(oneMinus2t);\n"); 967 builder->fsCodeAppend("\tminAbs = minAbs > 1.0 ? 1.0 : minAbs;\n"); 968 builder->fsCodeAppendf("\tcolorTemp += (1.0 - minAbs) * %s;\n", 969 builder->getUniformVariable(fColorMidUni).c_str()); 970 } else { 971 builder->fsCodeAppendf("\tcolorTemp += (1.0 - min(abs(oneMinus2t), 1.0)) * %s;\n", 972 builder->getUniformVariable(fColorMidUni).c_str()); 973 } 974 builder->fsCodeAppendf("\tcolorTemp += clamp(-oneMinus2t, 0.0, 1.0) * %s;\n", 975 builder->getUniformVariable(fColorEndUni).c_str()); 976 if (GrGradientEffect::kAfterInterp_PremulType == PremulTypeFromKey(key)) { 977 builder->fsCodeAppend("\tcolorTemp.rgb *= colorTemp.a;\n"); 978 } 979 980 builder->fsCodeAppendf("\t%s = %s;\n", outputColor, 981 (GrGLSLExpr4(inputColor) * GrGLSLExpr4("colorTemp")).c_str()); 982 } else { 983 builder->fsCodeAppendf("\tvec2 coord = vec2(%s, %s);\n", 984 gradientTValue, 985 builder->getUniformVariable(fFSYUni).c_str()); 986 builder->fsCodeAppendf("\t%s = ", outputColor); 987 builder->fsAppendTextureLookupAndModulate(inputColor, 988 samplers[0], 989 "coord"); 990 builder->fsCodeAppend(";\n"); 991 } 992} 993 994///////////////////////////////////////////////////////////////////// 995 996GrGradientEffect::GrGradientEffect(GrContext* ctx, 997 const SkGradientShaderBase& shader, 998 const SkMatrix& matrix, 999 SkShader::TileMode tileMode) { 1000 1001 fIsOpaque = shader.isOpaque(); 1002 1003 SkShader::GradientInfo info; 1004 SkScalar pos[3] = {0}; 1005 1006 info.fColorCount = 3; 1007 info.fColors = &fColors[0]; 1008 info.fColorOffsets = &pos[0]; 1009 shader.asAGradient(&info); 1010 1011 // The two and three color specializations do not currently support tiling. 1012 bool foundSpecialCase = false; 1013 if (SkShader::kClamp_TileMode == info.fTileMode) { 1014 if (2 == info.fColorCount) { 1015 fRow = -1; // flag for no atlas 1016 fColorType = kTwo_ColorType; 1017 foundSpecialCase = true; 1018 } else if (3 == info.fColorCount && 1019 (SkScalarAbs(pos[1] - SK_ScalarHalf) < SK_Scalar1 / 1000)) { // 3 color symmetric 1020 fRow = -1; // flag for no atlas 1021 fColorType = kThree_ColorType; 1022 foundSpecialCase = true; 1023 } 1024 } 1025 if (foundSpecialCase) { 1026 if (SkGradientShader::kInterpolateColorsInPremul_Flag & info.fGradientFlags) { 1027 fPremulType = kBeforeInterp_PremulType; 1028 } else { 1029 fPremulType = kAfterInterp_PremulType; 1030 } 1031 fCoordTransform.reset(kCoordSet, matrix); 1032 } else { 1033 // doesn't matter how this is set, just be consistent because it is part of the effect key. 1034 fPremulType = kBeforeInterp_PremulType; 1035 SkBitmap bitmap; 1036 shader.getGradientTableBitmap(&bitmap); 1037 fColorType = kTexture_ColorType; 1038 1039 GrTextureStripAtlas::Desc desc; 1040 desc.fWidth = bitmap.width(); 1041 desc.fHeight = 32; 1042 desc.fRowHeight = bitmap.height(); 1043 desc.fContext = ctx; 1044 desc.fConfig = SkBitmapConfig2GrPixelConfig(bitmap.config()); 1045 fAtlas = GrTextureStripAtlas::GetAtlas(desc); 1046 SkASSERT(NULL != fAtlas); 1047 1048 // We always filter the gradient table. Each table is one row of a texture, always y-clamp. 1049 GrTextureParams params; 1050 params.setFilterMode(GrTextureParams::kBilerp_FilterMode); 1051 params.setTileModeX(tileMode); 1052 1053 fRow = fAtlas->lockRow(bitmap); 1054 if (-1 != fRow) { 1055 fYCoord = fAtlas->getYOffset(fRow) + SK_ScalarHalf * 1056 fAtlas->getVerticalScaleFactor(); 1057 fCoordTransform.reset(kCoordSet, matrix, fAtlas->getTexture()); 1058 fTextureAccess.reset(fAtlas->getTexture(), params); 1059 } else { 1060 GrTexture* texture = GrLockAndRefCachedBitmapTexture(ctx, bitmap, ¶ms); 1061 fCoordTransform.reset(kCoordSet, matrix, texture); 1062 fTextureAccess.reset(texture, params); 1063 fYCoord = SK_ScalarHalf; 1064 1065 // Unlock immediately, this is not great, but we don't have a way of 1066 // knowing when else to unlock it currently, so it may get purged from 1067 // the cache, but it'll still be ref'd until it's no longer being used. 1068 GrUnlockAndUnrefCachedBitmapTexture(texture); 1069 } 1070 this->addTextureAccess(&fTextureAccess); 1071 } 1072 this->addCoordTransform(&fCoordTransform); 1073} 1074 1075GrGradientEffect::~GrGradientEffect() { 1076 if (this->useAtlas()) { 1077 fAtlas->unlockRow(fRow); 1078 } 1079} 1080 1081bool GrGradientEffect::onIsEqual(const GrEffect& effect) const { 1082 const GrGradientEffect& s = CastEffect<GrGradientEffect>(effect); 1083 1084 if (this->fColorType == s.getColorType()){ 1085 1086 if (kTwo_ColorType == fColorType) { 1087 if (*this->getColors(0) != *s.getColors(0) || 1088 *this->getColors(1) != *s.getColors(1)) { 1089 return false; 1090 } 1091 } else if (kThree_ColorType == fColorType) { 1092 if (*this->getColors(0) != *s.getColors(0) || 1093 *this->getColors(1) != *s.getColors(1) || 1094 *this->getColors(2) != *s.getColors(2)) { 1095 return false; 1096 } 1097 } else { 1098 if (fYCoord != s.getYCoord()) { 1099 return false; 1100 } 1101 } 1102 1103 return fTextureAccess.getTexture() == s.fTextureAccess.getTexture() && 1104 fTextureAccess.getParams().getTileModeX() == 1105 s.fTextureAccess.getParams().getTileModeX() && 1106 this->useAtlas() == s.useAtlas() && 1107 fCoordTransform.getMatrix().cheapEqualTo(s.fCoordTransform.getMatrix()); 1108 } 1109 1110 return false; 1111} 1112 1113void GrGradientEffect::getConstantColorComponents(GrColor* color, uint32_t* validFlags) const { 1114 if (fIsOpaque && (kA_GrColorComponentFlag & *validFlags) && 0xff == GrColorUnpackA(*color)) { 1115 *validFlags = kA_GrColorComponentFlag; 1116 } else { 1117 *validFlags = 0; 1118 } 1119} 1120 1121int GrGradientEffect::RandomGradientParams(SkRandom* random, 1122 SkColor colors[], 1123 SkScalar** stops, 1124 SkShader::TileMode* tm) { 1125 int outColors = random->nextRangeU(1, kMaxRandomGradientColors); 1126 1127 // if one color, omit stops, otherwise randomly decide whether or not to 1128 if (outColors == 1 || (outColors >= 2 && random->nextBool())) { 1129 *stops = NULL; 1130 } 1131 1132 SkScalar stop = 0.f; 1133 for (int i = 0; i < outColors; ++i) { 1134 colors[i] = random->nextU(); 1135 if (NULL != *stops) { 1136 (*stops)[i] = stop; 1137 stop = i < outColors - 1 ? stop + random->nextUScalar1() * (1.f - stop) : 1.f; 1138 } 1139 } 1140 *tm = static_cast<SkShader::TileMode>(random->nextULessThan(SkShader::kTileModeCount)); 1141 1142 return outColors; 1143} 1144 1145#endif 1146