1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
|
/*
* Copyright 2006 The Android Open Source Project
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include <algorithm>
#include "Sk4fLinearGradient.h"
#include "SkColorSpace_XYZ.h"
#include "SkColorSpaceXformer.h"
#include "SkFloatBits.h"
#include "SkGradientBitmapCache.h"
#include "SkGradientShaderPriv.h"
#include "SkHalf.h"
#include "SkLinearGradient.h"
#include "SkMallocPixelRef.h"
#include "SkRadialGradient.h"
#include "SkReadBuffer.h"
#include "SkSweepGradient.h"
#include "SkTwoPointConicalGradient.h"
#include "SkWriteBuffer.h"
#include "../../jumper/SkJumper.h"
enum GradientSerializationFlags {
// Bits 29:31 used for various boolean flags
kHasPosition_GSF = 0x80000000,
kHasLocalMatrix_GSF = 0x40000000,
kHasColorSpace_GSF = 0x20000000,
// Bits 12:28 unused
// Bits 8:11 for fTileMode
kTileModeShift_GSF = 8,
kTileModeMask_GSF = 0xF,
// Bits 0:7 for fGradFlags (note that kForce4fContext_PrivateFlag is 0x80)
kGradFlagsShift_GSF = 0,
kGradFlagsMask_GSF = 0xFF,
};
void SkGradientShaderBase::Descriptor::flatten(SkWriteBuffer& buffer) const {
uint32_t flags = 0;
if (fPos) {
flags |= kHasPosition_GSF;
}
if (fLocalMatrix) {
flags |= kHasLocalMatrix_GSF;
}
sk_sp<SkData> colorSpaceData = fColorSpace ? fColorSpace->serialize() : nullptr;
if (colorSpaceData) {
flags |= kHasColorSpace_GSF;
}
SkASSERT(static_cast<uint32_t>(fTileMode) <= kTileModeMask_GSF);
flags |= (fTileMode << kTileModeShift_GSF);
SkASSERT(fGradFlags <= kGradFlagsMask_GSF);
flags |= (fGradFlags << kGradFlagsShift_GSF);
buffer.writeUInt(flags);
buffer.writeColor4fArray(fColors, fCount);
if (colorSpaceData) {
buffer.writeDataAsByteArray(colorSpaceData.get());
}
if (fPos) {
buffer.writeScalarArray(fPos, fCount);
}
if (fLocalMatrix) {
buffer.writeMatrix(*fLocalMatrix);
}
}
bool SkGradientShaderBase::DescriptorScope::unflatten(SkReadBuffer& buffer) {
// New gradient format. Includes floating point color, color space, densely packed flags
uint32_t flags = buffer.readUInt();
fTileMode = (SkShader::TileMode)((flags >> kTileModeShift_GSF) & kTileModeMask_GSF);
fGradFlags = (flags >> kGradFlagsShift_GSF) & kGradFlagsMask_GSF;
fCount = buffer.getArrayCount();
if (fCount > kStorageCount) {
size_t allocSize = (sizeof(SkColor4f) + sizeof(SkScalar)) * fCount;
fDynamicStorage.reset(allocSize);
fColors = (SkColor4f*)fDynamicStorage.get();
fPos = (SkScalar*)(fColors + fCount);
} else {
fColors = fColorStorage;
fPos = fPosStorage;
}
if (!buffer.readColor4fArray(mutableColors(), fCount)) {
return false;
}
if (SkToBool(flags & kHasColorSpace_GSF)) {
sk_sp<SkData> data = buffer.readByteArrayAsData();
fColorSpace = SkColorSpace::Deserialize(data->data(), data->size());
} else {
fColorSpace = nullptr;
}
if (SkToBool(flags & kHasPosition_GSF)) {
if (!buffer.readScalarArray(mutablePos(), fCount)) {
return false;
}
} else {
fPos = nullptr;
}
if (SkToBool(flags & kHasLocalMatrix_GSF)) {
fLocalMatrix = &fLocalMatrixStorage;
buffer.readMatrix(&fLocalMatrixStorage);
} else {
fLocalMatrix = nullptr;
}
return buffer.isValid();
}
////////////////////////////////////////////////////////////////////////////////////////////
SkGradientShaderBase::SkGradientShaderBase(const Descriptor& desc, const SkMatrix& ptsToUnit)
: INHERITED(desc.fLocalMatrix)
, fPtsToUnit(ptsToUnit)
, fColorsAreOpaque(true)
{
fPtsToUnit.getType(); // Precache so reads are threadsafe.
SkASSERT(desc.fCount > 1);
fGradFlags = static_cast<uint8_t>(desc.fGradFlags);
SkASSERT((unsigned)desc.fTileMode < SkShader::kTileModeCount);
fTileMode = desc.fTileMode;
/* Note: we let the caller skip the first and/or last position.
i.e. pos[0] = 0.3, pos[1] = 0.7
In these cases, we insert dummy entries to ensure that the final data
will be bracketed by [0, 1].
i.e. our_pos[0] = 0, our_pos[1] = 0.3, our_pos[2] = 0.7, our_pos[3] = 1
Thus colorCount (the caller's value, and fColorCount (our value) may
differ by up to 2. In the above example:
colorCount = 2
fColorCount = 4
*/
fColorCount = desc.fCount;
// check if we need to add in dummy start and/or end position/colors
bool dummyFirst = false;
bool dummyLast = false;
if (desc.fPos) {
dummyFirst = desc.fPos[0] != 0;
dummyLast = desc.fPos[desc.fCount - 1] != SK_Scalar1;
fColorCount += dummyFirst + dummyLast;
}
size_t storageSize = fColorCount * (sizeof(SkColor4f) + (desc.fPos ? sizeof(SkScalar) : 0));
fOrigColors4f = reinterpret_cast<SkColor4f*>(fStorage.reset(storageSize));
fOrigPos = desc.fPos ? reinterpret_cast<SkScalar*>(fOrigColors4f + fColorCount)
: nullptr;
// Now copy over the colors, adding the dummies as needed
SkColor4f* origColors = fOrigColors4f;
if (dummyFirst) {
*origColors++ = desc.fColors[0];
}
for (int i = 0; i < desc.fCount; ++i) {
origColors[i] = desc.fColors[i];
fColorsAreOpaque = fColorsAreOpaque && (desc.fColors[i].fA == 1);
}
if (dummyLast) {
origColors += desc.fCount;
*origColors = desc.fColors[desc.fCount - 1];
}
if (!desc.fColorSpace) {
// This happens if we were constructed from SkColors, so our colors are really sRGB
fColorSpace = SkColorSpace::MakeSRGBLinear();
} else {
// The color space refers to the float colors, so it must be linear gamma
// TODO: GPU code no longer requires this (see GrGradientEffect). Remove this restriction?
SkASSERT(desc.fColorSpace->gammaIsLinear());
fColorSpace = desc.fColorSpace;
}
if (desc.fPos) {
SkScalar prev = 0;
SkScalar* origPosPtr = fOrigPos;
*origPosPtr++ = prev; // force the first pos to 0
int startIndex = dummyFirst ? 0 : 1;
int count = desc.fCount + dummyLast;
bool uniformStops = true;
const SkScalar uniformStep = desc.fPos[startIndex] - prev;
for (int i = startIndex; i < count; i++) {
// Pin the last value to 1.0, and make sure pos is monotonic.
auto curr = (i == desc.fCount) ? 1 : SkScalarPin(desc.fPos[i], prev, 1);
uniformStops &= SkScalarNearlyEqual(uniformStep, curr - prev);
*origPosPtr++ = prev = curr;
}
// If the stops are uniform, treat them as implicit.
if (uniformStops) {
fOrigPos = nullptr;
}
}
}
SkGradientShaderBase::~SkGradientShaderBase() {}
void SkGradientShaderBase::flatten(SkWriteBuffer& buffer) const {
Descriptor desc;
desc.fColors = fOrigColors4f;
desc.fColorSpace = fColorSpace;
desc.fPos = fOrigPos;
desc.fCount = fColorCount;
desc.fTileMode = fTileMode;
desc.fGradFlags = fGradFlags;
const SkMatrix& m = this->getLocalMatrix();
desc.fLocalMatrix = m.isIdentity() ? nullptr : &m;
desc.flatten(buffer);
}
static void add_stop_color(SkJumper_GradientCtx* ctx, size_t stop, SkPM4f Fs, SkPM4f Bs) {
(ctx->fs[0])[stop] = Fs.r();
(ctx->fs[1])[stop] = Fs.g();
(ctx->fs[2])[stop] = Fs.b();
(ctx->fs[3])[stop] = Fs.a();
(ctx->bs[0])[stop] = Bs.r();
(ctx->bs[1])[stop] = Bs.g();
(ctx->bs[2])[stop] = Bs.b();
(ctx->bs[3])[stop] = Bs.a();
}
static void add_const_color(SkJumper_GradientCtx* ctx, size_t stop, SkPM4f color) {
add_stop_color(ctx, stop, SkPM4f::FromPremulRGBA(0,0,0,0), color);
}
// Calculate a factor F and a bias B so that color = F*t + B when t is in range of
// the stop. Assume that the distance between stops is 1/gapCount.
static void init_stop_evenly(
SkJumper_GradientCtx* ctx, float gapCount, size_t stop, SkPM4f c_l, SkPM4f c_r) {
// Clankium's GCC 4.9 targeting ARMv7 is barfing when we use Sk4f math here, so go scalar...
SkPM4f Fs = {{
(c_r.r() - c_l.r()) * gapCount,
(c_r.g() - c_l.g()) * gapCount,
(c_r.b() - c_l.b()) * gapCount,
(c_r.a() - c_l.a()) * gapCount,
}};
SkPM4f Bs = {{
c_l.r() - Fs.r()*(stop/gapCount),
c_l.g() - Fs.g()*(stop/gapCount),
c_l.b() - Fs.b()*(stop/gapCount),
c_l.a() - Fs.a()*(stop/gapCount),
}};
add_stop_color(ctx, stop, Fs, Bs);
}
// For each stop we calculate a bias B and a scale factor F, such that
// for any t between stops n and n+1, the color we want is B[n] + F[n]*t.
static void init_stop_pos(
SkJumper_GradientCtx* ctx, size_t stop, float t_l, float t_r, SkPM4f c_l, SkPM4f c_r) {
// See note about Clankium's old compiler in init_stop_evenly().
SkPM4f Fs = {{
(c_r.r() - c_l.r()) / (t_r - t_l),
(c_r.g() - c_l.g()) / (t_r - t_l),
(c_r.b() - c_l.b()) / (t_r - t_l),
(c_r.a() - c_l.a()) / (t_r - t_l),
}};
SkPM4f Bs = {{
c_l.r() - Fs.r()*t_l,
c_l.g() - Fs.g()*t_l,
c_l.b() - Fs.b()*t_l,
c_l.a() - Fs.a()*t_l,
}};
ctx->ts[stop] = t_l;
add_stop_color(ctx, stop, Fs, Bs);
}
bool SkGradientShaderBase::onAppendStages(const StageRec& rec) const {
SkRasterPipeline* p = rec.fPipeline;
SkArenaAlloc* alloc = rec.fAlloc;
SkColorSpace* dstCS = rec.fDstCS;
SkJumper_DecalTileCtx* decal_ctx = nullptr;
SkMatrix matrix;
if (!this->computeTotalInverse(rec.fCTM, rec.fLocalM, &matrix)) {
return false;
}
matrix.postConcat(fPtsToUnit);
SkRasterPipeline_<256> postPipeline;
p->append_seed_shader();
p->append_matrix(alloc, matrix);
this->appendGradientStages(alloc, p, &postPipeline);
switch(fTileMode) {
case kMirror_TileMode: p->append(SkRasterPipeline::mirror_x_1); break;
case kRepeat_TileMode: p->append(SkRasterPipeline::repeat_x_1); break;
case kDecal_TileMode:
decal_ctx = alloc->make<SkJumper_DecalTileCtx>();
decal_ctx->limit_x = SkBits2Float(SkFloat2Bits(1.0f) + 1);
// reuse mask + limit_x stage, or create a custom decal_1 that just stores the mask
p->append(SkRasterPipeline::decal_x, decal_ctx);
// fall-through to clamp
case kClamp_TileMode:
if (!fOrigPos) {
// We clamp only when the stops are evenly spaced.
// If not, there may be hard stops, and clamping ruins hard stops at 0 and/or 1.
// In that case, we must make sure we're using the general "gradient" stage,
// which is the only stage that will correctly handle unclamped t.
p->append(SkRasterPipeline::clamp_x_1);
}
break;
}
const bool premulGrad = fGradFlags & SkGradientShader::kInterpolateColorsInPremul_Flag;
auto prepareColor = [premulGrad, dstCS, this](int i) {
SkColor4f c = this->getXformedColor(i, dstCS);
return premulGrad ? c.premul()
: SkPM4f::From4f(Sk4f::Load(&c));
};
// The two-stop case with stops at 0 and 1.
if (fColorCount == 2 && fOrigPos == nullptr) {
const SkPM4f c_l = prepareColor(0),
c_r = prepareColor(1);
// See F and B below.
auto* f_and_b = alloc->makeArrayDefault<SkPM4f>(2);
f_and_b[0] = SkPM4f::From4f(c_r.to4f() - c_l.to4f());
f_and_b[1] = c_l;
p->append(SkRasterPipeline::evenly_spaced_2_stop_gradient, f_and_b);
} else {
auto* ctx = alloc->make<SkJumper_GradientCtx>();
// Note: In order to handle clamps in search, the search assumes a stop conceptully placed
// at -inf. Therefore, the max number of stops is fColorCount+1.
for (int i = 0; i < 4; i++) {
// Allocate at least at for the AVX2 gather from a YMM register.
ctx->fs[i] = alloc->makeArray<float>(std::max(fColorCount+1, 8));
ctx->bs[i] = alloc->makeArray<float>(std::max(fColorCount+1, 8));
}
if (fOrigPos == nullptr) {
// Handle evenly distributed stops.
size_t stopCount = fColorCount;
float gapCount = stopCount - 1;
SkPM4f c_l = prepareColor(0);
for (size_t i = 0; i < stopCount - 1; i++) {
SkPM4f c_r = prepareColor(i + 1);
init_stop_evenly(ctx, gapCount, i, c_l, c_r);
c_l = c_r;
}
add_const_color(ctx, stopCount - 1, c_l);
ctx->stopCount = stopCount;
p->append(SkRasterPipeline::evenly_spaced_gradient, ctx);
} else {
// Handle arbitrary stops.
ctx->ts = alloc->makeArray<float>(fColorCount+1);
// Remove the dummy stops inserted by SkGradientShaderBase::SkGradientShaderBase
// because they are naturally handled by the search method.
int firstStop;
int lastStop;
if (fColorCount > 2) {
firstStop = fOrigColors4f[0] != fOrigColors4f[1] ? 0 : 1;
lastStop = fOrigColors4f[fColorCount - 2] != fOrigColors4f[fColorCount - 1]
? fColorCount - 1 : fColorCount - 2;
} else {
firstStop = 0;
lastStop = 1;
}
size_t stopCount = 0;
float t_l = fOrigPos[firstStop];
SkPM4f c_l = prepareColor(firstStop);
add_const_color(ctx, stopCount++, c_l);
// N.B. lastStop is the index of the last stop, not one after.
for (int i = firstStop; i < lastStop; i++) {
float t_r = fOrigPos[i + 1];
SkPM4f c_r = prepareColor(i + 1);
SkASSERT(t_l <= t_r);
if (t_l < t_r) {
init_stop_pos(ctx, stopCount, t_l, t_r, c_l, c_r);
stopCount += 1;
}
t_l = t_r;
c_l = c_r;
}
ctx->ts[stopCount] = t_l;
add_const_color(ctx, stopCount++, c_l);
ctx->stopCount = stopCount;
p->append(SkRasterPipeline::gradient, ctx);
}
}
if (decal_ctx) {
p->append(SkRasterPipeline::check_decal_mask, decal_ctx);
}
if (!premulGrad && !this->colorsAreOpaque()) {
p->append(SkRasterPipeline::premul);
}
p->extend(postPipeline);
return true;
}
bool SkGradientShaderBase::isOpaque() const {
return fColorsAreOpaque && (this->getTileMode() != SkShader::kDecal_TileMode);
}
bool SkGradientShaderBase::onIsRasterPipelineOnly(const SkMatrix& ctm) const {
if (this->getTileMode() == SkShader::kDecal_TileMode) {
return true;
}
return this->INHERITED::onIsRasterPipelineOnly(ctm);
}
static unsigned rounded_divide(unsigned numer, unsigned denom) {
return (numer + (denom >> 1)) / denom;
}
bool SkGradientShaderBase::onAsLuminanceColor(SkColor* lum) const {
// we just compute an average color.
// possibly we could weight this based on the proportional width for each color
// assuming they are not evenly distributed in the fPos array.
int r = 0;
int g = 0;
int b = 0;
const int n = fColorCount;
// TODO: use linear colors?
for (int i = 0; i < n; ++i) {
SkColor c = this->getLegacyColor(i);
r += SkColorGetR(c);
g += SkColorGetG(c);
b += SkColorGetB(c);
}
*lum = SkColorSetRGB(rounded_divide(r, n), rounded_divide(g, n), rounded_divide(b, n));
return true;
}
SkGradientShaderBase::AutoXformColors::AutoXformColors(const SkGradientShaderBase& grad,
SkColorSpaceXformer* xformer)
: fColors(grad.fColorCount) {
// TODO: stay in 4f to preserve precision?
SkAutoSTMalloc<8, SkColor> origColors(grad.fColorCount);
for (int i = 0; i < grad.fColorCount; ++i) {
origColors[i] = grad.getLegacyColor(i);
}
xformer->apply(fColors.get(), origColors.get(), grad.fColorCount);
}
static constexpr int kGradientTextureSize = 256;
void SkGradientShaderBase::initLinearBitmap(SkBitmap* bitmap, GradientBitmapType bitmapType) const {
const bool interpInPremul = SkToBool(fGradFlags &
SkGradientShader::kInterpolateColorsInPremul_Flag);
SkHalf* pixelsF16 = reinterpret_cast<SkHalf*>(bitmap->getPixels());
uint32_t* pixels32 = reinterpret_cast<uint32_t*>(bitmap->getPixels());
typedef std::function<void(const Sk4f&, int)> pixelWriteFn_t;
pixelWriteFn_t writeF16Pixel = [&](const Sk4f& x, int index) {
Sk4h c = SkFloatToHalf_finite_ftz(x);
pixelsF16[4*index+0] = c[0];
pixelsF16[4*index+1] = c[1];
pixelsF16[4*index+2] = c[2];
pixelsF16[4*index+3] = c[3];
};
pixelWriteFn_t writeS32Pixel = [&](const Sk4f& c, int index) {
pixels32[index] = Sk4f_toS32(c);
};
pixelWriteFn_t writeL32Pixel = [&](const Sk4f& c, int index) {
pixels32[index] = Sk4f_toL32(c);
};
pixelWriteFn_t writeSizedPixel =
(bitmapType == GradientBitmapType::kHalfFloat) ? writeF16Pixel :
(bitmapType == GradientBitmapType::kSRGB ) ? writeS32Pixel : writeL32Pixel;
pixelWriteFn_t writeUnpremulPixel = [&](const Sk4f& c, int index) {
writeSizedPixel(c * Sk4f(c[3], c[3], c[3], 1.0f), index);
};
pixelWriteFn_t writePixel = interpInPremul ? writeSizedPixel : writeUnpremulPixel;
// When not in legacy mode, we just want the original 4f colors - so we pass in
// our own CS for identity/no transform.
auto* cs = bitmapType != GradientBitmapType::kLegacy ? fColorSpace.get() : nullptr;
int prevIndex = 0;
for (int i = 1; i < fColorCount; i++) {
// Historically, stops have been mapped to [0, 256], with 256 then nudged to the
// next smaller value, then truncate for the texture index. This seems to produce
// the best results for some common distributions, so we preserve the behavior.
int nextIndex = SkTMin(this->getPos(i) * kGradientTextureSize,
SkIntToScalar(kGradientTextureSize - 1));
if (nextIndex > prevIndex) {
SkColor4f color0 = this->getXformedColor(i - 1, cs),
color1 = this->getXformedColor(i , cs);
Sk4f c0 = Sk4f::Load(color0.vec()),
c1 = Sk4f::Load(color1.vec());
if (interpInPremul) {
c0 = c0 * Sk4f(c0[3], c0[3], c0[3], 1.0f);
c1 = c1 * Sk4f(c1[3], c1[3], c1[3], 1.0f);
}
Sk4f step = Sk4f(1.0f / static_cast<float>(nextIndex - prevIndex));
Sk4f delta = (c1 - c0) * step;
for (int curIndex = prevIndex; curIndex <= nextIndex; ++curIndex) {
writePixel(c0, curIndex);
c0 += delta;
}
}
prevIndex = nextIndex;
}
SkASSERT(prevIndex == kGradientTextureSize - 1);
}
SkColor4f SkGradientShaderBase::getXformedColor(size_t i, SkColorSpace* dstCS) const {
if (dstCS) {
return to_colorspace(fOrigColors4f[i], fColorSpace.get(), dstCS);
}
// Legacy/srgb color.
// We quantize upfront to ensure stable SkColor round-trips.
auto rgb255 = sk_linear_to_srgb(Sk4f::Load(fOrigColors4f[i].vec()));
auto rgb = SkNx_cast<float>(rgb255) * (1/255.0f);
return { rgb[0], rgb[1], rgb[2], fOrigColors4f[i].fA };
}
SK_DECLARE_STATIC_MUTEX(gGradientCacheMutex);
/*
* Because our caller might rebuild the same (logically the same) gradient
* over and over, we'd like to return exactly the same "bitmap" if possible,
* allowing the client to utilize a cache of our bitmap (e.g. with a GPU).
* To do that, we maintain a private cache of built-bitmaps, based on our
* colors and positions.
*/
void SkGradientShaderBase::getGradientTableBitmap(SkBitmap* bitmap,
GradientBitmapType bitmapType) const {
// build our key: [numColors + colors[] + {positions[]} + flags + colorType ]
static_assert(sizeof(SkColor4f) % sizeof(int32_t) == 0, "");
const int colorsAsIntCount = fColorCount * sizeof(SkColor4f) / sizeof(int32_t);
int count = 1 + colorsAsIntCount + 1 + 1;
if (fColorCount > 2) {
count += fColorCount - 1;
}
SkAutoSTMalloc<64, int32_t> storage(count);
int32_t* buffer = storage.get();
*buffer++ = fColorCount;
memcpy(buffer, fOrigColors4f, fColorCount * sizeof(SkColor4f));
buffer += colorsAsIntCount;
if (fColorCount > 2) {
for (int i = 1; i < fColorCount; i++) {
*buffer++ = SkFloat2Bits(this->getPos(i));
}
}
*buffer++ = fGradFlags;
*buffer++ = static_cast<int32_t>(bitmapType);
SkASSERT(buffer - storage.get() == count);
///////////////////////////////////
static SkGradientBitmapCache* gCache;
// each cache cost 1K or 2K of RAM, since each bitmap will be 1x256 at either 32bpp or 64bpp
static const int MAX_NUM_CACHED_GRADIENT_BITMAPS = 32;
SkAutoMutexAcquire ama(gGradientCacheMutex);
if (nullptr == gCache) {
gCache = new SkGradientBitmapCache(MAX_NUM_CACHED_GRADIENT_BITMAPS);
}
size_t size = count * sizeof(int32_t);
if (!gCache->find(storage.get(), size, bitmap)) {
// For these cases we use the bitmap cache, but not the GradientShaderCache. So just
// allocate and populate the bitmap's data directly.
SkImageInfo info;
switch (bitmapType) {
case GradientBitmapType::kLegacy:
info = SkImageInfo::Make(kGradientTextureSize, 1, kRGBA_8888_SkColorType,
kPremul_SkAlphaType);
break;
case GradientBitmapType::kSRGB:
info = SkImageInfo::Make(kGradientTextureSize, 1, kRGBA_8888_SkColorType,
kPremul_SkAlphaType, SkColorSpace::MakeSRGB());
break;
case GradientBitmapType::kHalfFloat:
info = SkImageInfo::Make(kGradientTextureSize, 1, kRGBA_F16_SkColorType,
kPremul_SkAlphaType, SkColorSpace::MakeSRGBLinear());
break;
}
bitmap->allocPixels(info);
this->initLinearBitmap(bitmap, bitmapType);
bitmap->setImmutable();
gCache->add(storage.get(), size, *bitmap);
}
}
void SkGradientShaderBase::commonAsAGradient(GradientInfo* info) const {
if (info) {
if (info->fColorCount >= fColorCount) {
if (info->fColors) {
for (int i = 0; i < fColorCount; ++i) {
info->fColors[i] = this->getLegacyColor(i);
}
}
if (info->fColorOffsets) {
for (int i = 0; i < fColorCount; ++i) {
info->fColorOffsets[i] = this->getPos(i);
}
}
}
info->fColorCount = fColorCount;
info->fTileMode = fTileMode;
info->fGradientFlags = fGradFlags;
}
}
#ifndef SK_IGNORE_TO_STRING
void SkGradientShaderBase::toString(SkString* str) const {
str->appendf("%d colors: ", fColorCount);
for (int i = 0; i < fColorCount; ++i) {
str->appendHex(this->getLegacyColor(i), 8);
if (i < fColorCount-1) {
str->append(", ");
}
}
if (fColorCount > 2) {
str->append(" points: (");
for (int i = 0; i < fColorCount; ++i) {
str->appendScalar(this->getPos(i));
if (i < fColorCount-1) {
str->append(", ");
}
}
str->append(")");
}
static const char* gTileModeName[SkShader::kTileModeCount] = {
"clamp", "repeat", "mirror", "decal",
};
str->append(" ");
str->append(gTileModeName[fTileMode]);
this->INHERITED::toString(str);
}
#endif
///////////////////////////////////////////////////////////////////////////////
///////////////////////////////////////////////////////////////////////////////
// Return true if these parameters are valid/legal/safe to construct a gradient
//
static bool valid_grad(const SkColor4f colors[], const SkScalar pos[], int count,
unsigned tileMode) {
return nullptr != colors && count >= 1 && tileMode < (unsigned)SkShader::kTileModeCount;
}
static void desc_init(SkGradientShaderBase::Descriptor* desc,
const SkColor4f colors[], sk_sp<SkColorSpace> colorSpace,
const SkScalar pos[], int colorCount,
SkShader::TileMode mode, uint32_t flags, const SkMatrix* localMatrix) {
SkASSERT(colorCount > 1);
desc->fColors = colors;
desc->fColorSpace = std::move(colorSpace);
desc->fPos = pos;
desc->fCount = colorCount;
desc->fTileMode = mode;
desc->fGradFlags = flags;
desc->fLocalMatrix = localMatrix;
}
// assumes colors is SkColor4f* and pos is SkScalar*
#define EXPAND_1_COLOR(count) \
SkColor4f tmp[2]; \
do { \
if (1 == count) { \
tmp[0] = tmp[1] = colors[0]; \
colors = tmp; \
pos = nullptr; \
count = 2; \
} \
} while (0)
struct ColorStopOptimizer {
ColorStopOptimizer(const SkColor4f* colors, const SkScalar* pos,
int count, SkShader::TileMode mode)
: fColors(colors)
, fPos(pos)
, fCount(count) {
if (!pos || count != 3) {
return;
}
if (SkScalarNearlyEqual(pos[0], 0.0f) &&
SkScalarNearlyEqual(pos[1], 0.0f) &&
SkScalarNearlyEqual(pos[2], 1.0f)) {
if (SkShader::kRepeat_TileMode == mode ||
SkShader::kMirror_TileMode == mode ||
colors[0] == colors[1]) {
// Ignore the leftmost color/pos.
fColors += 1;
fPos += 1;
fCount = 2;
}
} else if (SkScalarNearlyEqual(pos[0], 0.0f) &&
SkScalarNearlyEqual(pos[1], 1.0f) &&
SkScalarNearlyEqual(pos[2], 1.0f)) {
if (SkShader::kRepeat_TileMode == mode ||
SkShader::kMirror_TileMode == mode ||
colors[1] == colors[2]) {
// Ignore the rightmost color/pos.
fCount = 2;
}
}
}
const SkColor4f* fColors;
const SkScalar* fPos;
int fCount;
};
struct ColorConverter {
ColorConverter(const SkColor* colors, int count) {
for (int i = 0; i < count; ++i) {
fColors4f.push_back(SkColor4f::FromColor(colors[i]));
}
}
SkSTArray<2, SkColor4f, true> fColors4f;
};
sk_sp<SkShader> SkGradientShader::MakeLinear(const SkPoint pts[2],
const SkColor colors[],
const SkScalar pos[], int colorCount,
SkShader::TileMode mode,
uint32_t flags,
const SkMatrix* localMatrix) {
ColorConverter converter(colors, colorCount);
return MakeLinear(pts, converter.fColors4f.begin(), nullptr, pos, colorCount, mode, flags,
localMatrix);
}
sk_sp<SkShader> SkGradientShader::MakeLinear(const SkPoint pts[2],
const SkColor4f colors[],
sk_sp<SkColorSpace> colorSpace,
const SkScalar pos[], int colorCount,
SkShader::TileMode mode,
uint32_t flags,
const SkMatrix* localMatrix) {
if (!pts || !SkScalarIsFinite((pts[1] - pts[0]).length())) {
return nullptr;
}
if (!valid_grad(colors, pos, colorCount, mode)) {
return nullptr;
}
if (1 == colorCount) {
return SkShader::MakeColorShader(colors[0], std::move(colorSpace));
}
if (localMatrix && !localMatrix->invert(nullptr)) {
return nullptr;
}
ColorStopOptimizer opt(colors, pos, colorCount, mode);
SkGradientShaderBase::Descriptor desc;
desc_init(&desc, opt.fColors, std::move(colorSpace), opt.fPos, opt.fCount, mode, flags,
localMatrix);
return sk_make_sp<SkLinearGradient>(pts, desc);
}
sk_sp<SkShader> SkGradientShader::MakeRadial(const SkPoint& center, SkScalar radius,
const SkColor colors[],
const SkScalar pos[], int colorCount,
SkShader::TileMode mode,
uint32_t flags,
const SkMatrix* localMatrix) {
ColorConverter converter(colors, colorCount);
return MakeRadial(center, radius, converter.fColors4f.begin(), nullptr, pos, colorCount, mode,
flags, localMatrix);
}
sk_sp<SkShader> SkGradientShader::MakeRadial(const SkPoint& center, SkScalar radius,
const SkColor4f colors[],
sk_sp<SkColorSpace> colorSpace,
const SkScalar pos[], int colorCount,
SkShader::TileMode mode,
uint32_t flags,
const SkMatrix* localMatrix) {
if (radius <= 0) {
return nullptr;
}
if (!valid_grad(colors, pos, colorCount, mode)) {
return nullptr;
}
if (1 == colorCount) {
return SkShader::MakeColorShader(colors[0], std::move(colorSpace));
}
if (localMatrix && !localMatrix->invert(nullptr)) {
return nullptr;
}
ColorStopOptimizer opt(colors, pos, colorCount, mode);
SkGradientShaderBase::Descriptor desc;
desc_init(&desc, opt.fColors, std::move(colorSpace), opt.fPos, opt.fCount, mode, flags,
localMatrix);
return sk_make_sp<SkRadialGradient>(center, radius, desc);
}
sk_sp<SkShader> SkGradientShader::MakeTwoPointConical(const SkPoint& start,
SkScalar startRadius,
const SkPoint& end,
SkScalar endRadius,
const SkColor colors[],
const SkScalar pos[],
int colorCount,
SkShader::TileMode mode,
uint32_t flags,
const SkMatrix* localMatrix) {
ColorConverter converter(colors, colorCount);
return MakeTwoPointConical(start, startRadius, end, endRadius, converter.fColors4f.begin(),
nullptr, pos, colorCount, mode, flags, localMatrix);
}
sk_sp<SkShader> SkGradientShader::MakeTwoPointConical(const SkPoint& start,
SkScalar startRadius,
const SkPoint& end,
SkScalar endRadius,
const SkColor4f colors[],
sk_sp<SkColorSpace> colorSpace,
const SkScalar pos[],
int colorCount,
SkShader::TileMode mode,
uint32_t flags,
const SkMatrix* localMatrix) {
if (startRadius < 0 || endRadius < 0) {
return nullptr;
}
if (SkScalarNearlyZero((start - end).length()) && SkScalarNearlyZero(startRadius)) {
// We can treat this gradient as radial, which is faster.
return MakeRadial(start, endRadius, colors, std::move(colorSpace), pos, colorCount,
mode, flags, localMatrix);
}
if (!valid_grad(colors, pos, colorCount, mode)) {
return nullptr;
}
if (startRadius == endRadius) {
if (start == end || startRadius == 0) {
return SkShader::MakeEmptyShader();
}
}
if (localMatrix && !localMatrix->invert(nullptr)) {
return nullptr;
}
EXPAND_1_COLOR(colorCount);
ColorStopOptimizer opt(colors, pos, colorCount, mode);
SkGradientShaderBase::Descriptor desc;
desc_init(&desc, opt.fColors, std::move(colorSpace), opt.fPos, opt.fCount, mode, flags,
localMatrix);
return SkTwoPointConicalGradient::Create(start, startRadius, end, endRadius, desc);
}
sk_sp<SkShader> SkGradientShader::MakeSweep(SkScalar cx, SkScalar cy,
const SkColor colors[],
const SkScalar pos[],
int colorCount,
SkShader::TileMode mode,
SkScalar startAngle,
SkScalar endAngle,
uint32_t flags,
const SkMatrix* localMatrix) {
ColorConverter converter(colors, colorCount);
return MakeSweep(cx, cy, converter.fColors4f.begin(), nullptr, pos, colorCount,
mode, startAngle, endAngle, flags, localMatrix);
}
sk_sp<SkShader> SkGradientShader::MakeSweep(SkScalar cx, SkScalar cy,
const SkColor4f colors[],
sk_sp<SkColorSpace> colorSpace,
const SkScalar pos[],
int colorCount,
SkShader::TileMode mode,
SkScalar startAngle,
SkScalar endAngle,
uint32_t flags,
const SkMatrix* localMatrix) {
if (!valid_grad(colors, pos, colorCount, mode)) {
return nullptr;
}
if (1 == colorCount) {
return SkShader::MakeColorShader(colors[0], std::move(colorSpace));
}
if (startAngle >= endAngle) {
return nullptr;
}
if (localMatrix && !localMatrix->invert(nullptr)) {
return nullptr;
}
if (startAngle <= 0 && endAngle >= 360) {
// If the t-range includes [0,1], then we can always use clamping (presumably faster).
mode = SkShader::kClamp_TileMode;
}
ColorStopOptimizer opt(colors, pos, colorCount, mode);
SkGradientShaderBase::Descriptor desc;
desc_init(&desc, opt.fColors, std::move(colorSpace), opt.fPos, opt.fCount, mode, flags,
localMatrix);
const SkScalar t0 = startAngle / 360,
t1 = endAngle / 360;
return sk_make_sp<SkSweepGradient>(SkPoint::Make(cx, cy), t0, t1, desc);
}
SK_DEFINE_FLATTENABLE_REGISTRAR_GROUP_START(SkGradientShader)
SK_DEFINE_FLATTENABLE_REGISTRAR_ENTRY(SkLinearGradient)
SK_DEFINE_FLATTENABLE_REGISTRAR_ENTRY(SkRadialGradient)
SK_DEFINE_FLATTENABLE_REGISTRAR_ENTRY(SkSweepGradient)
SK_DEFINE_FLATTENABLE_REGISTRAR_ENTRY(SkTwoPointConicalGradient)
SK_DEFINE_FLATTENABLE_REGISTRAR_GROUP_END
///////////////////////////////////////////////////////////////////////////////
#if SK_SUPPORT_GPU
#include "GrColorSpaceXform.h"
#include "GrContext.h"
#include "GrContextPriv.h"
#include "GrShaderCaps.h"
#include "GrTextureStripAtlas.h"
#include "gl/GrGLContext.h"
#include "glsl/GrGLSLFragmentShaderBuilder.h"
#include "glsl/GrGLSLProgramDataManager.h"
#include "glsl/GrGLSLUniformHandler.h"
#include "SkGr.h"
void GrGradientEffect::GLSLProcessor::emitUniforms(GrGLSLUniformHandler* uniformHandler,
const GrGradientEffect& ge) {
switch (ge.fStrategy) {
case GrGradientEffect::InterpolationStrategy::kThreshold:
case GrGradientEffect::InterpolationStrategy::kThresholdClamp0:
case GrGradientEffect::InterpolationStrategy::kThresholdClamp1:
fThresholdUni = uniformHandler->addUniform(kFragment_GrShaderFlag,
kFloat_GrSLType,
kHigh_GrSLPrecision,
"Threshold");
// fall through
case GrGradientEffect::InterpolationStrategy::kSingle:
fIntervalsUni = uniformHandler->addUniformArray(kFragment_GrShaderFlag,
kHalf4_GrSLType,
"Intervals",
ge.fIntervals.count());
break;
case GrGradientEffect::InterpolationStrategy::kTexture:
fFSYUni = uniformHandler->addUniform(kFragment_GrShaderFlag, kHalf_GrSLType,
"GradientYCoordFS");
break;
}
}
void GrGradientEffect::GLSLProcessor::onSetData(const GrGLSLProgramDataManager& pdman,
const GrFragmentProcessor& processor) {
const GrGradientEffect& e = processor.cast<GrGradientEffect>();
switch (e.fStrategy) {
case GrGradientEffect::InterpolationStrategy::kThreshold:
case GrGradientEffect::InterpolationStrategy::kThresholdClamp0:
case GrGradientEffect::InterpolationStrategy::kThresholdClamp1:
pdman.set1f(fThresholdUni, e.fThreshold);
// fall through
case GrGradientEffect::InterpolationStrategy::kSingle:
pdman.set4fv(fIntervalsUni, e.fIntervals.count(),
reinterpret_cast<const float*>(e.fIntervals.begin()));
break;
case GrGradientEffect::InterpolationStrategy::kTexture:
if (e.fYCoord != fCachedYCoord) {
pdman.set1f(fFSYUni, e.fYCoord);
fCachedYCoord = e.fYCoord;
}
break;
}
}
void GrGradientEffect::onGetGLSLProcessorKey(const GrShaderCaps&, GrProcessorKeyBuilder* b) const {
b->add32(GLSLProcessor::GenBaseGradientKey(*this));
}
uint32_t GrGradientEffect::GLSLProcessor::GenBaseGradientKey(const GrProcessor& processor) {
const GrGradientEffect& e = processor.cast<GrGradientEffect>();
// Build a key using the following bit allocation:
static constexpr uint32_t kStrategyBits = 3;
static constexpr uint32_t kPremulBits = 1;
SkDEBUGCODE(static constexpr uint32_t kWrapModeBits = 2;)
uint32_t key = static_cast<uint32_t>(e.fStrategy);
SkASSERT(key < (1 << kStrategyBits));
// This is already baked into the table for texture gradients,
// and only changes behavior for analytical gradients.
if (e.fStrategy != InterpolationStrategy::kTexture &&
e.fPremulType == GrGradientEffect::kBeforeInterp_PremulType) {
key |= 1 << kStrategyBits;
SkASSERT(key < (1 << (kStrategyBits + kPremulBits)));
}
key |= static_cast<uint32_t>(e.fWrapMode) << (kStrategyBits + kPremulBits);
SkASSERT(key < (1 << (kStrategyBits + kPremulBits + kWrapModeBits)));
return key;
}
void GrGradientEffect::GLSLProcessor::emitAnalyticalColor(GrGLSLFPFragmentBuilder* fragBuilder,
GrGLSLUniformHandler* uniformHandler,
const GrShaderCaps* shaderCaps,
const GrGradientEffect& ge,
const char* t,
const char* outputColor,
const char* inputColor) {
// First, apply tiling rules.
switch (ge.fWrapMode) {
case GrSamplerState::WrapMode::kClamp:
switch (ge.fStrategy) {
case GrGradientEffect::InterpolationStrategy::kThresholdClamp0:
// allow t > 1, in order to hit the clamp interval (1, inf)
fragBuilder->codeAppendf("half tiled_t = max(%s, 0.0);", t);
break;
case GrGradientEffect::InterpolationStrategy::kThresholdClamp1:
// allow t < 0, in order to hit the clamp interval (-inf, 0)
fragBuilder->codeAppendf("half tiled_t = min(%s, 1.0);", t);
break;
default:
// regular [0, 1] clamping
fragBuilder->codeAppendf("half tiled_t = clamp(%s, 0.0, 1.0);", t);
}
break;
case GrSamplerState::WrapMode::kRepeat:
fragBuilder->codeAppendf("half tiled_t = fract(%s);", t);
break;
case GrSamplerState::WrapMode::kMirrorRepeat:
fragBuilder->codeAppendf("half t_1 = %s - 1.0;", t);
fragBuilder->codeAppendf("half tiled_t = t_1 - 2.0 * floor(t_1 * 0.5) - 1.0;");
if (shaderCaps->mustDoOpBetweenFloorAndAbs()) {
// At this point the expected value of tiled_t should between -1 and 1, so this
// clamp has no effect other than to break up the floor and abs calls and make sure
// the compiler doesn't merge them back together.
fragBuilder->codeAppendf("tiled_t = clamp(tiled_t, -1.0, 1.0);");
}
fragBuilder->codeAppendf("tiled_t = abs(tiled_t);");
break;
}
// Calculate the color.
const char* intervals = uniformHandler->getUniformCStr(fIntervalsUni);
switch (ge.fStrategy) {
case GrGradientEffect::InterpolationStrategy::kSingle:
SkASSERT(ge.fIntervals.count() == 2);
fragBuilder->codeAppendf(
"half4 color_scale = %s[0],"
" color_bias = %s[1];"
, intervals, intervals
);
break;
case GrGradientEffect::InterpolationStrategy::kThreshold:
case GrGradientEffect::InterpolationStrategy::kThresholdClamp0:
case GrGradientEffect::InterpolationStrategy::kThresholdClamp1:
{
SkASSERT(ge.fIntervals.count() == 4);
const char* threshold = uniformHandler->getUniformCStr(fThresholdUni);
fragBuilder->codeAppendf(
"half4 color_scale, color_bias;"
"if (tiled_t < %s) {"
" color_scale = %s[0];"
" color_bias = %s[1];"
"} else {"
" color_scale = %s[2];"
" color_bias = %s[3];"
"}"
, threshold, intervals, intervals, intervals, intervals
);
} break;
default:
SkASSERT(false);
break;
}
fragBuilder->codeAppend("half4 colorTemp = tiled_t * color_scale + color_bias;");
// We could skip this step if all colors are known to be opaque. Two considerations:
// The gradient SkShader reporting opaque is more restrictive than necessary in the two
// pt case. Make sure the key reflects this optimization (and note that it can use the
// same shader as the kBeforeInterp case).
if (ge.fPremulType == GrGradientEffect::kAfterInterp_PremulType) {
fragBuilder->codeAppend("colorTemp.rgb *= colorTemp.a;");
}
// If the input colors were floats, or there was a color space xform, we may end up out of
// range. The simplest solution is to always clamp our (premul) value here. We only need to
// clamp RGB, but that causes hangs on the Tegra3 Nexus7. Clamping RGBA avoids the problem.
fragBuilder->codeAppend("colorTemp = clamp(colorTemp, 0, colorTemp.a);");
fragBuilder->codeAppendf("%s = %s * colorTemp;", outputColor, inputColor);
}
void GrGradientEffect::GLSLProcessor::emitColor(GrGLSLFPFragmentBuilder* fragBuilder,
GrGLSLUniformHandler* uniformHandler,
const GrShaderCaps* shaderCaps,
const GrGradientEffect& ge,
const char* gradientTValue,
const char* outputColor,
const char* inputColor,
const TextureSamplers& texSamplers) {
if (ge.fStrategy != InterpolationStrategy::kTexture) {
this->emitAnalyticalColor(fragBuilder, uniformHandler, shaderCaps, ge, gradientTValue,
outputColor, inputColor);
return;
}
const char* fsyuni = uniformHandler->getUniformCStr(fFSYUni);
fragBuilder->codeAppendf("half2 coord = half2(%s, %s);", gradientTValue, fsyuni);
fragBuilder->codeAppendf("%s = ", outputColor);
fragBuilder->appendTextureLookupAndModulate(inputColor, texSamplers[0], "coord",
kFloat2_GrSLType);
fragBuilder->codeAppend(";");
}
/////////////////////////////////////////////////////////////////////
inline GrFragmentProcessor::OptimizationFlags GrGradientEffect::OptFlags(bool isOpaque) {
return isOpaque
? kPreservesOpaqueInput_OptimizationFlag |
kCompatibleWithCoverageAsAlpha_OptimizationFlag
: kCompatibleWithCoverageAsAlpha_OptimizationFlag;
}
void GrGradientEffect::addInterval(const SkGradientShaderBase& shader, size_t idx0, size_t idx1,
SkColorSpace* dstCS) {
SkASSERT(idx0 <= idx1);
const auto c4f0 = shader.getXformedColor(idx0, dstCS),
c4f1 = shader.getXformedColor(idx1, dstCS);
const auto c0 = (fPremulType == kBeforeInterp_PremulType)
? c4f0.premul().to4f() : Sk4f::Load(c4f0.vec()),
c1 = (fPremulType == kBeforeInterp_PremulType)
? c4f1.premul().to4f() : Sk4f::Load(c4f1.vec());
const auto t0 = shader.getPos(idx0),
t1 = shader.getPos(idx1),
dt = t1 - t0;
SkASSERT(dt >= 0);
// dt can be 0 for clamp intervals => in this case we want a scale == 0
const auto scale = SkScalarNearlyZero(dt) ? 0 : (c1 - c0) / dt,
bias = c0 - t0 * scale;
// Intervals are stored as (scale, bias) tuples.
SkASSERT(!(fIntervals.count() & 1));
fIntervals.emplace_back(scale[0], scale[1], scale[2], scale[3]);
fIntervals.emplace_back( bias[0], bias[1], bias[2], bias[3]);
}
GrGradientEffect::GrGradientEffect(ClassID classID, const CreateArgs& args, bool isOpaque)
: INHERITED(classID, OptFlags(isOpaque))
, fWrapMode(args.fWrapMode)
, fRow(-1)
, fIsOpaque(args.fShader->isOpaque())
, fStrategy(InterpolationStrategy::kTexture)
, fThreshold(0) {
const SkGradientShaderBase& shader(*args.fShader);
fPremulType = (args.fShader->getGradFlags() & SkGradientShader::kInterpolateColorsInPremul_Flag)
? kBeforeInterp_PremulType : kAfterInterp_PremulType;
// First, determine the interpolation strategy and params.
switch (shader.fColorCount) {
case 2:
SkASSERT(!shader.fOrigPos);
fStrategy = InterpolationStrategy::kSingle;
this->addInterval(shader, 0, 1, args.fDstColorSpace);
break;
case 3:
fThreshold = shader.getPos(1);
if (shader.fOrigPos) {
SkASSERT(SkScalarNearlyEqual(shader.fOrigPos[0], 0));
SkASSERT(SkScalarNearlyEqual(shader.fOrigPos[2], 1));
if (SkScalarNearlyEqual(shader.fOrigPos[1], 0)) {
// hard stop on the left edge.
if (fWrapMode == GrSamplerState::WrapMode::kClamp) {
fStrategy = InterpolationStrategy::kThresholdClamp1;
// Clamp interval (scale == 0, bias == colors[0]).
this->addInterval(shader, 0, 0, args.fDstColorSpace);
} else {
// We can ignore the hard stop when not clamping.
fStrategy = InterpolationStrategy::kSingle;
}
this->addInterval(shader, 1, 2, args.fDstColorSpace);
break;
}
if (SkScalarNearlyEqual(shader.fOrigPos[1], 1)) {
// hard stop on the right edge.
this->addInterval(shader, 0, 1, args.fDstColorSpace);
if (fWrapMode == GrSamplerState::WrapMode::kClamp) {
fStrategy = InterpolationStrategy::kThresholdClamp0;
// Clamp interval (scale == 0, bias == colors[2]).
this->addInterval(shader, 2, 2, args.fDstColorSpace);
} else {
// We can ignore the hard stop when not clamping.
fStrategy = InterpolationStrategy::kSingle;
}
break;
}
}
// Two arbitrary interpolation intervals.
fStrategy = InterpolationStrategy::kThreshold;
this->addInterval(shader, 0, 1, args.fDstColorSpace);
this->addInterval(shader, 1, 2, args.fDstColorSpace);
break;
case 4:
if (shader.fOrigPos && SkScalarNearlyEqual(shader.fOrigPos[1], shader.fOrigPos[2])) {
SkASSERT(SkScalarNearlyEqual(shader.fOrigPos[0], 0));
SkASSERT(SkScalarNearlyEqual(shader.fOrigPos[3], 1));
// Single hard stop => two arbitrary interpolation intervals.
fStrategy = InterpolationStrategy::kThreshold;
fThreshold = shader.getPos(1);
this->addInterval(shader, 0, 1, args.fDstColorSpace);
this->addInterval(shader, 2, 3, args.fDstColorSpace);
}
break;
default:
break;
}
// Now that we've locked down a strategy, adjust any dependent params.
if (fStrategy != InterpolationStrategy::kTexture) {
// Analytical cases.
fCoordTransform.reset(*args.fMatrix);
} else {
SkGradientShaderBase::GradientBitmapType bitmapType =
SkGradientShaderBase::GradientBitmapType::kLegacy;
if (args.fDstColorSpace) {
// Try to use F16 if we can
if (args.fContext->caps()->isConfigTexturable(kRGBA_half_GrPixelConfig)) {
bitmapType = SkGradientShaderBase::GradientBitmapType::kHalfFloat;
} else if (args.fContext->caps()->isConfigTexturable(kSRGBA_8888_GrPixelConfig)) {
bitmapType = SkGradientShaderBase::GradientBitmapType::kSRGB;
} else {
// This can happen, but only if someone explicitly creates an unsupported
// (eg sRGB) surface. Just fall back to legacy behavior.
}
}
SkBitmap bitmap;
shader.getGradientTableBitmap(&bitmap, bitmapType);
SkASSERT(1 == bitmap.height() && SkIsPow2(bitmap.width()));
auto atlasManager = args.fContext->contextPriv().textureStripAtlasManager();
GrTextureStripAtlas::Desc desc;
desc.fWidth = bitmap.width();
desc.fHeight = 32;
desc.fRowHeight = bitmap.height(); // always 1 here
desc.fConfig = SkImageInfo2GrPixelConfig(bitmap.info(), *args.fContext->caps());
fAtlas = atlasManager->getAtlas(desc);
SkASSERT(fAtlas);
// We always filter the gradient table. Each table is one row of a texture, always
// y-clamp.
GrSamplerState samplerState(args.fWrapMode, GrSamplerState::Filter::kBilerp);
fRow = fAtlas->lockRow(args.fContext, bitmap);
if (-1 != fRow) {
fYCoord = fAtlas->getYOffset(fRow)+SK_ScalarHalf*fAtlas->getNormalizedTexelHeight();
// This is 1/2 places where auto-normalization is disabled
fCoordTransform.reset(*args.fMatrix, fAtlas->asTextureProxyRef().get(), false);
fTextureSampler.reset(fAtlas->asTextureProxyRef(), samplerState);
} else {
// In this instance we know the samplerState state is:
// clampY, bilerp
// and the proxy is:
// exact fit, power of two in both dimensions
// Only the x-tileMode is unknown. However, given all the other knowns we know
// that GrMakeCachedImageProxy is sufficient (i.e., it won't need to be
// extracted to a subset or mipmapped).
SkASSERT(bitmap.isImmutable());
sk_sp<SkImage> srcImage = SkImage::MakeFromBitmap(bitmap);
if (!srcImage) {
return;
}
sk_sp<GrTextureProxy> proxy = GrMakeCachedImageProxy(
args.fContext->contextPriv().proxyProvider(),
std::move(srcImage));
if (!proxy) {
SkDebugf("Gradient won't draw. Could not create texture.");
return;
}
// This is 2/2 places where auto-normalization is disabled
fCoordTransform.reset(*args.fMatrix, proxy.get(), false);
fTextureSampler.reset(std::move(proxy), samplerState);
fYCoord = SK_ScalarHalf;
}
this->addTextureSampler(&fTextureSampler);
}
this->addCoordTransform(&fCoordTransform);
}
GrGradientEffect::GrGradientEffect(const GrGradientEffect& that)
: INHERITED(that.classID(), OptFlags(that.fIsOpaque))
, fIntervals(that.fIntervals)
, fWrapMode(that.fWrapMode)
, fCoordTransform(that.fCoordTransform)
, fTextureSampler(that.fTextureSampler)
, fYCoord(that.fYCoord)
, fAtlas(that.fAtlas)
, fRow(that.fRow)
, fIsOpaque(that.fIsOpaque)
, fStrategy(that.fStrategy)
, fThreshold(that.fThreshold)
, fPremulType(that.fPremulType) {
this->addCoordTransform(&fCoordTransform);
if (fStrategy == InterpolationStrategy::kTexture) {
this->addTextureSampler(&fTextureSampler);
}
if (this->useAtlas()) {
fAtlas->lockRow(fRow);
}
}
GrGradientEffect::~GrGradientEffect() {
if (this->useAtlas()) {
fAtlas->unlockRow(fRow);
}
}
bool GrGradientEffect::onIsEqual(const GrFragmentProcessor& processor) const {
const GrGradientEffect& ge = processor.cast<GrGradientEffect>();
if (fWrapMode != ge.fWrapMode || fStrategy != ge.fStrategy) {
return false;
}
SkASSERT(this->useAtlas() == ge.useAtlas());
if (fStrategy == InterpolationStrategy::kTexture) {
if (fYCoord != ge.fYCoord) {
return false;
}
} else {
if (fThreshold != ge.fThreshold ||
fIntervals != ge.fIntervals ||
fPremulType != ge.fPremulType) {
return false;
}
}
return true;
}
#if GR_TEST_UTILS
GrGradientEffect::RandomGradientParams::RandomGradientParams(SkRandom* random) {
// Set color count to min of 2 so that we don't trigger the const color optimization and make
// a non-gradient processor.
fColorCount = random->nextRangeU(2, kMaxRandomGradientColors);
fUseColors4f = random->nextBool();
// if one color, omit stops, otherwise randomly decide whether or not to
if (fColorCount == 1 || (fColorCount >= 2 && random->nextBool())) {
fStops = nullptr;
} else {
fStops = fStopStorage;
}
// if using SkColor4f, attach a random (possibly null) color space (with linear gamma)
if (fUseColors4f) {
fColorSpace = GrTest::TestColorSpace(random);
if (fColorSpace) {
fColorSpace = fColorSpace->makeLinearGamma();
}
}
SkScalar stop = 0.f;
for (int i = 0; i < fColorCount; ++i) {
if (fUseColors4f) {
fColors4f[i].fR = random->nextUScalar1();
fColors4f[i].fG = random->nextUScalar1();
fColors4f[i].fB = random->nextUScalar1();
fColors4f[i].fA = random->nextUScalar1();
} else {
fColors[i] = random->nextU();
}
if (fStops) {
fStops[i] = stop;
stop = i < fColorCount - 1 ? stop + random->nextUScalar1() * (1.f - stop) : 1.f;
}
}
fTileMode = static_cast<SkShader::TileMode>(random->nextULessThan(SkShader::kTileModeCount));
}
#endif
#endif
|