gfx/skia/trunk/src/effects/gradients/SkGradientShader.cpp@b8a032363ba2
gfx/skia/trunk/src/effects/gradients/SkGradientShader.cpp
Thu, 22 Jan 2015 13:21:57 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Thu, 22 Jan 2015 13:21:57 +0100
- branch
- TOR_BUG_9701
- changeset 15
- b8a032363ba2
- permissions
- -rw-r--r--
Incorporate requested changes from Mozilla in review:
https://bugzilla.mozilla.org/show_bug.cgi?id=1123480#c6
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 */
8 #include "SkGradientShaderPriv.h"
9 #include "SkLinearGradient.h"
10 #include "SkRadialGradient.h"
11 #include "SkTwoPointRadialGradient.h"
12 #include "SkTwoPointConicalGradient.h"
13 #include "SkSweepGradient.h"
15 SkGradientShaderBase::SkGradientShaderBase(const Descriptor& desc) {
16 SkASSERT(desc.fCount > 1);
18 fCacheAlpha = 256; // init to a value that paint.getAlpha() can't return
20 fMapper = desc.fMapper;
21 SkSafeRef(fMapper);
22 fGradFlags = SkToU8(desc.fFlags);
24 SkASSERT((unsigned)desc.fTileMode < SkShader::kTileModeCount);
25 SkASSERT(SkShader::kTileModeCount == SK_ARRAY_COUNT(gTileProcs));
26 fTileMode = desc.fTileMode;
27 fTileProc = gTileProcs[desc.fTileMode];
29 fCache16 = fCache16Storage = NULL;
30 fCache32 = NULL;
31 fCache32PixelRef = NULL;
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
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 }
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 }
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 }
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 }
132 static 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 }
138 static SkShader::TileMode unpack_mode(uint32_t packed) {
139 return (SkShader::TileMode)(packed & 0xF);
140 }
142 static uint32_t unpack_flags(uint32_t packed) {
143 return packed >> 4;
144 }
146 SkGradientShaderBase::SkGradientShaderBase(SkReadBuffer& buffer) : INHERITED(buffer) {
147 fCacheAlpha = 256;
149 fMapper = buffer.readUnitMapper();
151 fCache16 = fCache16Storage = NULL;
152 fCache32 = NULL;
153 fCache32PixelRef = NULL;
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);
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 }
188 SkGradientShaderBase::~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 }
199 void 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 }
208 void SkGradientShaderBase::flatten(SkWriteBuffer& 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 }
223 bool SkGradientShaderBase::isOpaque() const {
224 return fColorsAreOpaque;
225 }
227 bool 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 }
234 const SkMatrix& inverse = this->getTotalInverse();
236 if (!fDstToIndex.setConcat(fPtsToUnit, inverse)) {
237 // need to keep our set/end context calls balanced.
238 this->INHERITED::endContext();
239 return false;
240 }
242 fDstToIndexProc = fDstToIndex.getMapXYProc();
243 fDstToIndexClass = (uint8_t)SkShader::ComputeMatrixClass(fDstToIndex);
245 // now convert our colors in to PMColors
246 unsigned paintAlpha = this->getPaintAlpha();
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 }
258 this->setCacheAlpha(paintAlpha);
259 return true;
260 }
262 void 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 }
277 #define Fixed_To_Dot8(x) (((x) + 0x80) >> 8)
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 */
283 void 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);
289 SkFixed r = SkColorGetR(c0);
290 SkFixed g = SkColorGetG(c0);
291 SkFixed b = SkColorGetB(c0);
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);
297 r = SkIntToFixed(r) + 0x8000;
298 g = SkIntToFixed(g) + 0x8000;
299 b = SkIntToFixed(b) + 0x8000;
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 }
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 */
330 typedef uint32_t SkUFixed;
332 void SkGradientShaderBase::Build32bitCache(SkPMColor cache[], SkColor c0, SkColor c1,
333 int count, U8CPU paintAlpha, uint32_t gradFlags) {
334 SkASSERT(count > 1);
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);
341 const bool interpInPremul = SkToBool(gradFlags &
342 SkGradientShader::kInterpolateColorsInPremul_Flag);
344 uint32_t r0 = SkColorGetR(c0);
345 uint32_t g0 = SkColorGetG(c0);
346 uint32_t b0 = SkColorGetB(c0);
348 uint32_t r1 = SkColorGetR(c1);
349 uint32_t g1 = SkColorGetG(c1);
350 uint32_t b1 = SkColorGetB(c1);
352 if (interpInPremul) {
353 r0 = SkMulDiv255Round(r0, a0);
354 g0 = SkMulDiv255Round(g0, a0);
355 b0 = SkMulDiv255Round(b0, a0);
357 r1 = SkMulDiv255Round(r1, a1);
358 g1 = SkMulDiv255Round(g1, a1);
359 b1 = SkMulDiv255Round(b1, a1);
360 }
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);
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;
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 */
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 }
459 static inline int SkFixedToFFFF(SkFixed x) {
460 SkASSERT((unsigned)x <= SK_Fixed1);
461 return x - (x >> 16);
462 }
464 static 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 }
476 const 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;
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);
496 if (nextIndex > prevIndex)
497 Build16bitCache(fCache16 + prevIndex, fOrigColors[i-1], fOrigColors[i], nextIndex - prevIndex + 1);
498 prevIndex = nextIndex;
499 }
500 }
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 }
519 const 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;
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);
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 }
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 }
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 */
577 void 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);
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->setConfig(SkImageInfo::MakeN32Premul(kCache32Count, 1));
587 bitmap->setPixelRef(fCache32PixelRef);
588 return;
589 }
591 // build our key: [numColors + colors[] + {positions[]} + flags ]
592 int count = 1 + fColorCount + 1;
593 if (fColorCount > 2) {
594 count += fColorCount - 1; // fRecs[].fPos
595 }
597 SkAutoSTMalloc<16, int32_t> storage(count);
598 int32_t* buffer = storage.get();
600 *buffer++ = fColorCount;
601 memcpy(buffer, fOrigColors, fColorCount * sizeof(SkColor));
602 buffer += fColorCount;
603 if (fColorCount > 2) {
604 for (int i = 1; i < fColorCount; i++) {
605 *buffer++ = fRecs[i].fPos;
606 }
607 }
608 *buffer++ = fGradFlags;
609 SkASSERT(buffer - storage.get() == count);
611 ///////////////////////////////////
613 SK_DECLARE_STATIC_MUTEX(gMutex);
614 static SkBitmapCache* gCache;
615 // each cache cost 1K of RAM, since each bitmap will be 1x256 at 32bpp
616 static const int MAX_NUM_CACHED_GRADIENT_BITMAPS = 32;
617 SkAutoMutexAcquire ama(gMutex);
619 if (NULL == gCache) {
620 gCache = SkNEW_ARGS(SkBitmapCache, (MAX_NUM_CACHED_GRADIENT_BITMAPS));
621 }
622 size_t size = count * sizeof(int32_t);
624 if (!gCache->find(storage.get(), size, bitmap)) {
625 // force our cahce32pixelref to be built
626 (void)this->getCache32();
627 bitmap->setConfig(SkImageInfo::MakeN32Premul(kCache32Count, 1));
628 bitmap->setPixelRef(fCache32PixelRef);
630 gCache->add(storage.get(), size, *bitmap);
631 }
632 }
634 void SkGradientShaderBase::commonAsAGradient(GradientInfo* info) const {
635 if (info) {
636 if (info->fColorCount >= fColorCount) {
637 if (info->fColors) {
638 memcpy(info->fColors, fOrigColors, fColorCount * sizeof(SkColor));
639 }
640 if (info->fColorOffsets) {
641 if (fColorCount == 2) {
642 info->fColorOffsets[0] = 0;
643 info->fColorOffsets[1] = SK_Scalar1;
644 } else if (fColorCount > 2) {
645 for (int i = 0; i < fColorCount; ++i) {
646 info->fColorOffsets[i] = SkFixedToScalar(fRecs[i].fPos);
647 }
648 }
649 }
650 }
651 info->fColorCount = fColorCount;
652 info->fTileMode = fTileMode;
653 info->fGradientFlags = fGradFlags;
654 }
655 }
657 #ifndef SK_IGNORE_TO_STRING
658 void SkGradientShaderBase::toString(SkString* str) const {
660 str->appendf("%d colors: ", fColorCount);
662 for (int i = 0; i < fColorCount; ++i) {
663 str->appendHex(fOrigColors[i]);
664 if (i < fColorCount-1) {
665 str->append(", ");
666 }
667 }
669 if (fColorCount > 2) {
670 str->append(" points: (");
671 for (int i = 0; i < fColorCount; ++i) {
672 str->appendScalar(SkFixedToScalar(fRecs[i].fPos));
673 if (i < fColorCount-1) {
674 str->append(", ");
675 }
676 }
677 str->append(")");
678 }
680 static const char* gTileModeName[SkShader::kTileModeCount] = {
681 "clamp", "repeat", "mirror"
682 };
684 str->append(" ");
685 str->append(gTileModeName[fTileMode]);
687 // TODO: add "fMapper->toString(str);" when SkUnitMapper::toString is added
689 this->INHERITED::toString(str);
690 }
691 #endif
693 ///////////////////////////////////////////////////////////////////////////////
694 ///////////////////////////////////////////////////////////////////////////////
696 #include "SkEmptyShader.h"
698 // assumes colors is SkColor* and pos is SkScalar*
699 #define EXPAND_1_COLOR(count) \
700 SkColor tmp[2]; \
701 do { \
702 if (1 == count) { \
703 tmp[0] = tmp[1] = colors[0]; \
704 colors = tmp; \
705 pos = NULL; \
706 count = 2; \
707 } \
708 } while (0)
710 static void desc_init(SkGradientShaderBase::Descriptor* desc,
711 const SkColor colors[],
712 const SkScalar pos[], int colorCount,
713 SkShader::TileMode mode,
714 SkUnitMapper* mapper, uint32_t flags) {
715 desc->fColors = colors;
716 desc->fPos = pos;
717 desc->fCount = colorCount;
718 desc->fTileMode = mode;
719 desc->fMapper = mapper;
720 desc->fFlags = flags;
721 }
723 SkShader* SkGradientShader::CreateLinear(const SkPoint pts[2],
724 const SkColor colors[],
725 const SkScalar pos[], int colorCount,
726 SkShader::TileMode mode,
727 SkUnitMapper* mapper,
728 uint32_t flags) {
729 if (NULL == pts || NULL == colors || colorCount < 1) {
730 return NULL;
731 }
732 EXPAND_1_COLOR(colorCount);
734 SkGradientShaderBase::Descriptor desc;
735 desc_init(&desc, colors, pos, colorCount, mode, mapper, flags);
736 return SkNEW_ARGS(SkLinearGradient, (pts, desc));
737 }
739 SkShader* SkGradientShader::CreateRadial(const SkPoint& center, SkScalar radius,
740 const SkColor colors[],
741 const SkScalar pos[], int colorCount,
742 SkShader::TileMode mode,
743 SkUnitMapper* mapper,
744 uint32_t flags) {
745 if (radius <= 0 || NULL == colors || colorCount < 1) {
746 return NULL;
747 }
748 EXPAND_1_COLOR(colorCount);
750 SkGradientShaderBase::Descriptor desc;
751 desc_init(&desc, colors, pos, colorCount, mode, mapper, flags);
752 return SkNEW_ARGS(SkRadialGradient, (center, radius, desc));
753 }
755 SkShader* SkGradientShader::CreateTwoPointRadial(const SkPoint& start,
756 SkScalar startRadius,
757 const SkPoint& end,
758 SkScalar endRadius,
759 const SkColor colors[],
760 const SkScalar pos[],
761 int colorCount,
762 SkShader::TileMode mode,
763 SkUnitMapper* mapper,
764 uint32_t flags) {
765 if (startRadius < 0 || endRadius < 0 || NULL == colors || colorCount < 1) {
766 return NULL;
767 }
768 EXPAND_1_COLOR(colorCount);
770 SkGradientShaderBase::Descriptor desc;
771 desc_init(&desc, colors, pos, colorCount, mode, mapper, flags);
772 return SkNEW_ARGS(SkTwoPointRadialGradient,
773 (start, startRadius, end, endRadius, desc));
774 }
776 SkShader* SkGradientShader::CreateTwoPointConical(const SkPoint& start,
777 SkScalar startRadius,
778 const SkPoint& end,
779 SkScalar endRadius,
780 const SkColor colors[],
781 const SkScalar pos[],
782 int colorCount,
783 SkShader::TileMode mode,
784 SkUnitMapper* mapper,
785 uint32_t flags) {
786 if (startRadius < 0 || endRadius < 0 || NULL == colors || colorCount < 1) {
787 return NULL;
788 }
789 if (start == end && startRadius == endRadius) {
790 return SkNEW(SkEmptyShader);
791 }
792 EXPAND_1_COLOR(colorCount);
794 SkGradientShaderBase::Descriptor desc;
795 desc_init(&desc, colors, pos, colorCount, mode, mapper, flags);
796 return SkNEW_ARGS(SkTwoPointConicalGradient,
797 (start, startRadius, end, endRadius, desc));
798 }
800 SkShader* SkGradientShader::CreateSweep(SkScalar cx, SkScalar cy,
801 const SkColor colors[],
802 const SkScalar pos[],
803 int colorCount, SkUnitMapper* mapper,
804 uint32_t flags) {
805 if (NULL == colors || colorCount < 1) {
806 return NULL;
807 }
808 EXPAND_1_COLOR(colorCount);
810 SkGradientShaderBase::Descriptor desc;
811 desc_init(&desc, colors, pos, colorCount, SkShader::kClamp_TileMode, mapper, flags);
812 return SkNEW_ARGS(SkSweepGradient, (cx, cy, desc));
813 }
815 SK_DEFINE_FLATTENABLE_REGISTRAR_GROUP_START(SkGradientShader)
816 SK_DEFINE_FLATTENABLE_REGISTRAR_ENTRY(SkLinearGradient)
817 SK_DEFINE_FLATTENABLE_REGISTRAR_ENTRY(SkRadialGradient)
818 SK_DEFINE_FLATTENABLE_REGISTRAR_ENTRY(SkSweepGradient)
819 SK_DEFINE_FLATTENABLE_REGISTRAR_ENTRY(SkTwoPointRadialGradient)
820 SK_DEFINE_FLATTENABLE_REGISTRAR_ENTRY(SkTwoPointConicalGradient)
821 SK_DEFINE_FLATTENABLE_REGISTRAR_GROUP_END
823 ///////////////////////////////////////////////////////////////////////////////
825 #if SK_SUPPORT_GPU
827 #include "effects/GrTextureStripAtlas.h"
828 #include "GrTBackendEffectFactory.h"
829 #include "SkGr.h"
831 GrGLGradientEffect::GrGLGradientEffect(const GrBackendEffectFactory& factory)
832 : INHERITED(factory)
833 , fCachedYCoord(SK_ScalarMax) {
834 }
836 GrGLGradientEffect::~GrGLGradientEffect() { }
838 void GrGLGradientEffect::emitUniforms(GrGLShaderBuilder* builder, EffectKey key) {
840 if (GrGradientEffect::kTwo_ColorType == ColorTypeFromKey(key)) { // 2 Color case
841 fColorStartUni = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility,
842 kVec4f_GrSLType, "GradientStartColor");
843 fColorEndUni = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility,
844 kVec4f_GrSLType, "GradientEndColor");
846 } else if (GrGradientEffect::kThree_ColorType == ColorTypeFromKey(key)){ // 3 Color Case
847 fColorStartUni = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility,
848 kVec4f_GrSLType, "GradientStartColor");
849 fColorMidUni = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility,
850 kVec4f_GrSLType, "GradientMidColor");
851 fColorEndUni = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility,
852 kVec4f_GrSLType, "GradientEndColor");
854 } else { // if not a fast case
855 fFSYUni = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility,
856 kFloat_GrSLType, "GradientYCoordFS");
857 }
858 }
860 static inline void set_color_uni(const GrGLUniformManager& uman,
861 const GrGLUniformManager::UniformHandle uni,
862 const SkColor* color) {
863 uman.set4f(uni,
864 SkColorGetR(*color) / 255.f,
865 SkColorGetG(*color) / 255.f,
866 SkColorGetB(*color) / 255.f,
867 SkColorGetA(*color) / 255.f);
868 }
870 static inline void set_mul_color_uni(const GrGLUniformManager& uman,
871 const GrGLUniformManager::UniformHandle uni,
872 const SkColor* color){
873 float a = SkColorGetA(*color) / 255.f;
874 float aDiv255 = a / 255.f;
875 uman.set4f(uni,
876 SkColorGetR(*color) * aDiv255,
877 SkColorGetG(*color) * aDiv255,
878 SkColorGetB(*color) * aDiv255,
879 a);
880 }
882 void GrGLGradientEffect::setData(const GrGLUniformManager& uman,
883 const GrDrawEffect& drawEffect) {
885 const GrGradientEffect& e = drawEffect.castEffect<GrGradientEffect>();
888 if (GrGradientEffect::kTwo_ColorType == e.getColorType()){
890 if (GrGradientEffect::kBeforeInterp_PremulType == e.getPremulType()) {
891 set_mul_color_uni(uman, fColorStartUni, e.getColors(0));
892 set_mul_color_uni(uman, fColorEndUni, e.getColors(1));
893 } else {
894 set_color_uni(uman, fColorStartUni, e.getColors(0));
895 set_color_uni(uman, fColorEndUni, e.getColors(1));
896 }
898 } else if (GrGradientEffect::kThree_ColorType == e.getColorType()){
900 if (GrGradientEffect::kBeforeInterp_PremulType == e.getPremulType()) {
901 set_mul_color_uni(uman, fColorStartUni, e.getColors(0));
902 set_mul_color_uni(uman, fColorMidUni, e.getColors(1));
903 set_mul_color_uni(uman, fColorEndUni, e.getColors(2));
904 } else {
905 set_color_uni(uman, fColorStartUni, e.getColors(0));
906 set_color_uni(uman, fColorMidUni, e.getColors(1));
907 set_color_uni(uman, fColorEndUni, e.getColors(2));
908 }
909 } else {
911 SkScalar yCoord = e.getYCoord();
912 if (yCoord != fCachedYCoord) {
913 uman.set1f(fFSYUni, yCoord);
914 fCachedYCoord = yCoord;
915 }
916 }
917 }
920 GrGLEffect::EffectKey GrGLGradientEffect::GenBaseGradientKey(const GrDrawEffect& drawEffect) {
921 const GrGradientEffect& e = drawEffect.castEffect<GrGradientEffect>();
923 EffectKey key = 0;
925 if (GrGradientEffect::kTwo_ColorType == e.getColorType()) {
926 key |= kTwoColorKey;
927 } else if (GrGradientEffect::kThree_ColorType == e.getColorType()){
928 key |= kThreeColorKey;
929 }
931 if (GrGradientEffect::kBeforeInterp_PremulType == e.getPremulType()) {
932 key |= kPremulBeforeInterpKey;
933 }
935 return key;
936 }
938 void GrGLGradientEffect::emitColor(GrGLShaderBuilder* builder,
939 const char* gradientTValue,
940 EffectKey key,
941 const char* outputColor,
942 const char* inputColor,
943 const TextureSamplerArray& samplers) {
944 if (GrGradientEffect::kTwo_ColorType == ColorTypeFromKey(key)){
945 builder->fsCodeAppendf("\tvec4 colorTemp = mix(%s, %s, clamp(%s, 0.0, 1.0));\n",
946 builder->getUniformVariable(fColorStartUni).c_str(),
947 builder->getUniformVariable(fColorEndUni).c_str(),
948 gradientTValue);
949 // Note that we could skip this step if both colors are known to be opaque. Two
950 // considerations:
951 // The gradient SkShader reporting opaque is more restrictive than necessary in the two pt
952 // case. Make sure the key reflects this optimization (and note that it can use the same
953 // shader as thekBeforeIterp case). This same optimization applies to the 3 color case below.
954 if (GrGradientEffect::kAfterInterp_PremulType == PremulTypeFromKey(key)) {
955 builder->fsCodeAppend("\tcolorTemp.rgb *= colorTemp.a;\n");
956 }
958 builder->fsCodeAppendf("\t%s = %s;\n", outputColor,
959 (GrGLSLExpr4(inputColor) * GrGLSLExpr4("colorTemp")).c_str());
960 } else if (GrGradientEffect::kThree_ColorType == ColorTypeFromKey(key)){
961 builder->fsCodeAppendf("\tfloat oneMinus2t = 1.0 - (2.0 * (%s));\n",
962 gradientTValue);
963 builder->fsCodeAppendf("\tvec4 colorTemp = clamp(oneMinus2t, 0.0, 1.0) * %s;\n",
964 builder->getUniformVariable(fColorStartUni).c_str());
965 if (kTegra3_GrGLRenderer == builder->ctxInfo().renderer()) {
966 // The Tegra3 compiler will sometimes never return if we have
967 // min(abs(oneMinus2t), 1.0), or do the abs first in a separate expression.
968 builder->fsCodeAppend("\tfloat minAbs = abs(oneMinus2t);\n");
969 builder->fsCodeAppend("\tminAbs = minAbs > 1.0 ? 1.0 : minAbs;\n");
970 builder->fsCodeAppendf("\tcolorTemp += (1.0 - minAbs) * %s;\n",
971 builder->getUniformVariable(fColorMidUni).c_str());
972 } else {
973 builder->fsCodeAppendf("\tcolorTemp += (1.0 - min(abs(oneMinus2t), 1.0)) * %s;\n",
974 builder->getUniformVariable(fColorMidUni).c_str());
975 }
976 builder->fsCodeAppendf("\tcolorTemp += clamp(-oneMinus2t, 0.0, 1.0) * %s;\n",
977 builder->getUniformVariable(fColorEndUni).c_str());
978 if (GrGradientEffect::kAfterInterp_PremulType == PremulTypeFromKey(key)) {
979 builder->fsCodeAppend("\tcolorTemp.rgb *= colorTemp.a;\n");
980 }
982 builder->fsCodeAppendf("\t%s = %s;\n", outputColor,
983 (GrGLSLExpr4(inputColor) * GrGLSLExpr4("colorTemp")).c_str());
984 } else {
985 builder->fsCodeAppendf("\tvec2 coord = vec2(%s, %s);\n",
986 gradientTValue,
987 builder->getUniformVariable(fFSYUni).c_str());
988 builder->fsCodeAppendf("\t%s = ", outputColor);
989 builder->fsAppendTextureLookupAndModulate(inputColor,
990 samplers[0],
991 "coord");
992 builder->fsCodeAppend(";\n");
993 }
994 }
996 /////////////////////////////////////////////////////////////////////
998 GrGradientEffect::GrGradientEffect(GrContext* ctx,
999 const SkGradientShaderBase& shader,
1000 const SkMatrix& matrix,
1001 SkShader::TileMode tileMode) {
1003 fIsOpaque = shader.isOpaque();
1005 SkShader::GradientInfo info;
1006 SkScalar pos[3] = {0};
1008 info.fColorCount = 3;
1009 info.fColors = &fColors[0];
1010 info.fColorOffsets = &pos[0];
1011 shader.asAGradient(&info);
1013 // The two and three color specializations do not currently support tiling.
1014 bool foundSpecialCase = false;
1015 if (SkShader::kClamp_TileMode == info.fTileMode) {
1016 if (2 == info.fColorCount) {
1017 fRow = -1; // flag for no atlas
1018 fColorType = kTwo_ColorType;
1019 foundSpecialCase = true;
1020 } else if (3 == info.fColorCount &&
1021 (SkScalarAbs(pos[1] - SK_ScalarHalf) < SK_Scalar1 / 1000)) { // 3 color symmetric
1022 fRow = -1; // flag for no atlas
1023 fColorType = kThree_ColorType;
1024 foundSpecialCase = true;
1025 }
1026 }
1027 if (foundSpecialCase) {
1028 if (SkGradientShader::kInterpolateColorsInPremul_Flag & info.fGradientFlags) {
1029 fPremulType = kBeforeInterp_PremulType;
1030 } else {
1031 fPremulType = kAfterInterp_PremulType;
1032 }
1033 fCoordTransform.reset(kCoordSet, matrix);
1034 } else {
1035 // doesn't matter how this is set, just be consistent because it is part of the effect key.
1036 fPremulType = kBeforeInterp_PremulType;
1037 SkBitmap bitmap;
1038 shader.getGradientTableBitmap(&bitmap);
1039 fColorType = kTexture_ColorType;
1041 GrTextureStripAtlas::Desc desc;
1042 desc.fWidth = bitmap.width();
1043 desc.fHeight = 32;
1044 desc.fRowHeight = bitmap.height();
1045 desc.fContext = ctx;
1046 desc.fConfig = SkImageInfo2GrPixelConfig(bitmap.colorType(), bitmap.alphaType());
1047 fAtlas = GrTextureStripAtlas::GetAtlas(desc);
1048 SkASSERT(NULL != fAtlas);
1050 // We always filter the gradient table. Each table is one row of a texture, always y-clamp.
1051 GrTextureParams params;
1052 params.setFilterMode(GrTextureParams::kBilerp_FilterMode);
1053 params.setTileModeX(tileMode);
1055 fRow = fAtlas->lockRow(bitmap);
1056 if (-1 != fRow) {
1057 fYCoord = fAtlas->getYOffset(fRow) + SK_ScalarHalf *
1058 fAtlas->getVerticalScaleFactor();
1059 fCoordTransform.reset(kCoordSet, matrix, fAtlas->getTexture());
1060 fTextureAccess.reset(fAtlas->getTexture(), params);
1061 } else {
1062 GrTexture* texture = GrLockAndRefCachedBitmapTexture(ctx, bitmap, ¶ms);
1063 fCoordTransform.reset(kCoordSet, matrix, texture);
1064 fTextureAccess.reset(texture, params);
1065 fYCoord = SK_ScalarHalf;
1067 // Unlock immediately, this is not great, but we don't have a way of
1068 // knowing when else to unlock it currently, so it may get purged from
1069 // the cache, but it'll still be ref'd until it's no longer being used.
1070 GrUnlockAndUnrefCachedBitmapTexture(texture);
1071 }
1072 this->addTextureAccess(&fTextureAccess);
1073 }
1074 this->addCoordTransform(&fCoordTransform);
1075 }
1077 GrGradientEffect::~GrGradientEffect() {
1078 if (this->useAtlas()) {
1079 fAtlas->unlockRow(fRow);
1080 }
1081 }
1083 bool GrGradientEffect::onIsEqual(const GrEffect& effect) const {
1084 const GrGradientEffect& s = CastEffect<GrGradientEffect>(effect);
1086 if (this->fColorType == s.getColorType()){
1088 if (kTwo_ColorType == fColorType) {
1089 if (*this->getColors(0) != *s.getColors(0) ||
1090 *this->getColors(1) != *s.getColors(1)) {
1091 return false;
1092 }
1093 } else if (kThree_ColorType == fColorType) {
1094 if (*this->getColors(0) != *s.getColors(0) ||
1095 *this->getColors(1) != *s.getColors(1) ||
1096 *this->getColors(2) != *s.getColors(2)) {
1097 return false;
1098 }
1099 } else {
1100 if (fYCoord != s.getYCoord()) {
1101 return false;
1102 }
1103 }
1105 return fTextureAccess.getTexture() == s.fTextureAccess.getTexture() &&
1106 fTextureAccess.getParams().getTileModeX() ==
1107 s.fTextureAccess.getParams().getTileModeX() &&
1108 this->useAtlas() == s.useAtlas() &&
1109 fCoordTransform.getMatrix().cheapEqualTo(s.fCoordTransform.getMatrix());
1110 }
1112 return false;
1113 }
1115 void GrGradientEffect::getConstantColorComponents(GrColor* color, uint32_t* validFlags) const {
1116 if (fIsOpaque && (kA_GrColorComponentFlag & *validFlags) && 0xff == GrColorUnpackA(*color)) {
1117 *validFlags = kA_GrColorComponentFlag;
1118 } else {
1119 *validFlags = 0;
1120 }
1121 }
1123 int GrGradientEffect::RandomGradientParams(SkRandom* random,
1124 SkColor colors[],
1125 SkScalar** stops,
1126 SkShader::TileMode* tm) {
1127 int outColors = random->nextRangeU(1, kMaxRandomGradientColors);
1129 // if one color, omit stops, otherwise randomly decide whether or not to
1130 if (outColors == 1 || (outColors >= 2 && random->nextBool())) {
1131 *stops = NULL;
1132 }
1134 SkScalar stop = 0.f;
1135 for (int i = 0; i < outColors; ++i) {
1136 colors[i] = random->nextU();
1137 if (NULL != *stops) {
1138 (*stops)[i] = stop;
1139 stop = i < outColors - 1 ? stop + random->nextUScalar1() * (1.f - stop) : 1.f;
1140 }
1141 }
1142 *tm = static_cast<SkShader::TileMode>(random->nextULessThan(SkShader::kTileModeCount));
1144 return outColors;
1145 }
1147 #endif
