summaryrefslogtreecommitdiffstats
path: root/gfx/layers/opengl/CompositorOGL.cpp
blob: 4cafbea88a5e2f71853a5d2fe00ab38c093532f9 (plain)
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
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "CompositorOGL.h"
#include <stddef.h>             // for size_t
#include <stdint.h>             // for uint32_t, uint8_t
#include <stdlib.h>             // for free, malloc
#include "GLContextProvider.h"  // for GLContextProvider
#include "GLContext.h"          // for GLContext
#include "GLUploadHelpers.h"
#include "gfxCrashReporterUtils.h"  // for ScopedGfxFeatureReporter
#include "gfxEnv.h"                 // for gfxEnv
#include "gfxPlatform.h"            // for gfxPlatform
#include "gfxRect.h"                // for gfxRect
#include "gfxUtils.h"               // for gfxUtils, etc
#include "mozilla/ArrayUtils.h"     // for ArrayLength
#include "mozilla/Preferences.h"    // for Preferences
#include "mozilla/ProfilerLabels.h"
#include "mozilla/StaticPrefs_gfx.h"
#include "mozilla/StaticPrefs_layers.h"
#include "mozilla/StaticPrefs_nglayout.h"
#include "mozilla/gfx/BasePoint.h"  // for BasePoint
#include "mozilla/gfx/Matrix.h"     // for Matrix4x4, Matrix
#include "mozilla/gfx/Triangle.h"   // for Triangle
#include "mozilla/gfx/gfxVars.h"    // for gfxVars
#include "mozilla/layers/ImageDataSerializer.h"
#include "mozilla/layers/NativeLayer.h"
#include "mozilla/layers/CompositingRenderTargetOGL.h"
#include "mozilla/layers/Effects.h"      // for EffectChain, TexturedEffect, etc
#include "mozilla/layers/TextureHost.h"  // for TextureSource, etc
#include "mozilla/layers/TextureHostOGL.h"  // for TextureSourceOGL, etc
#include "mozilla/layers/PTextureParent.h"  // for OtherPid() on PTextureParent
#include "mozilla/mozalloc.h"               // for operator delete, etc
#include "nsAppRunner.h"
#include "nsAString.h"
#include "nsClassHashtable.h"
#include "nsIConsoleService.h"      // for nsIConsoleService, etc
#include "nsIWidget.h"              // for nsIWidget
#include "nsLiteralString.h"        // for NS_LITERAL_STRING
#include "nsMathUtils.h"            // for NS_roundf
#include "nsRect.h"                 // for mozilla::gfx::IntRect
#include "nsServiceManagerUtils.h"  // for do_GetService
#include "nsString.h"               // for nsString, nsAutoCString, etc
#include "OGLShaderProgram.h"       // for ShaderProgramOGL, etc
#include "ScopedGLHelpers.h"
#include "GLReadTexImageHelper.h"
#include "HeapCopyOfStackArray.h"
#include "GLBlitHelper.h"
#include "mozilla/gfx/Swizzle.h"
#ifdef MOZ_WAYLAND
#  include "mozilla/widget/GtkCompositorWidget.h"
#endif
#if MOZ_WIDGET_ANDROID
#  include "GLContextEGL.h"
#  include "GLLibraryEGL.h"
#  include "mozilla/java/GeckoSurfaceTextureWrappers.h"
#  include "mozilla/layers/AndroidHardwareBuffer.h"
#endif

namespace mozilla {

using namespace gfx;

namespace layers {

using namespace mozilla::gl;

static const GLuint kCoordinateAttributeIndex = 0;
static const GLuint kTexCoordinateAttributeIndex = 1;

class AsyncReadbackBufferOGL final : public AsyncReadbackBuffer {
 public:
  AsyncReadbackBufferOGL(GLContext* aGL, const IntSize& aSize);

  bool MapAndCopyInto(DataSourceSurface* aSurface,
                      const IntSize& aReadSize) const override;

  void Bind() const {
    mGL->fBindBuffer(LOCAL_GL_PIXEL_PACK_BUFFER, mBufferHandle);
    mGL->fPixelStorei(LOCAL_GL_PACK_ALIGNMENT, 1);
  }

 protected:
  virtual ~AsyncReadbackBufferOGL();

 private:
  GLContext* mGL;
  GLuint mBufferHandle;
};

AsyncReadbackBufferOGL::AsyncReadbackBufferOGL(GLContext* aGL,
                                               const IntSize& aSize)
    : AsyncReadbackBuffer(aSize), mGL(aGL), mBufferHandle(0) {
  size_t bufferByteCount = mSize.width * mSize.height * 4;
  mGL->fGenBuffers(1, &mBufferHandle);

  ScopedPackState scopedPackState(mGL);
  Bind();
  mGL->fBufferData(LOCAL_GL_PIXEL_PACK_BUFFER, bufferByteCount, nullptr,
                   LOCAL_GL_STREAM_READ);
}

AsyncReadbackBufferOGL::~AsyncReadbackBufferOGL() {
  if (mGL && mGL->MakeCurrent()) {
    mGL->fDeleteBuffers(1, &mBufferHandle);
  }
}

bool AsyncReadbackBufferOGL::MapAndCopyInto(DataSourceSurface* aSurface,
                                            const IntSize& aReadSize) const {
  MOZ_RELEASE_ASSERT(aReadSize <= aSurface->GetSize());

  if (!mGL || !mGL->MakeCurrent()) {
    return false;
  }

  ScopedPackState scopedPackState(mGL);
  Bind();

  const uint8_t* srcData = nullptr;
  if (mGL->IsSupported(GLFeature::map_buffer_range)) {
    srcData = static_cast<uint8_t*>(mGL->fMapBufferRange(
        LOCAL_GL_PIXEL_PACK_BUFFER, 0, aReadSize.height * aReadSize.width * 4,
        LOCAL_GL_MAP_READ_BIT));
  } else {
    srcData = static_cast<uint8_t*>(
        mGL->fMapBuffer(LOCAL_GL_PIXEL_PACK_BUFFER, LOCAL_GL_READ_ONLY));
  }

  if (!srcData) {
    return false;
  }

  int32_t srcStride = mSize.width * 4;  // Bind() sets an alignment of 1
  DataSourceSurface::ScopedMap map(aSurface, DataSourceSurface::WRITE);
  uint8_t* destData = map.GetData();
  int32_t destStride = map.GetStride();
  SurfaceFormat destFormat = aSurface->GetFormat();
  for (int32_t destRow = 0; destRow < aReadSize.height; destRow++) {
    // Turn srcData upside down during the copy.
    int32_t srcRow = aReadSize.height - 1 - destRow;
    const uint8_t* src = &srcData[srcRow * srcStride];
    uint8_t* dest = &destData[destRow * destStride];
    SwizzleData(src, srcStride, SurfaceFormat::R8G8B8A8, dest, destStride,
                destFormat, IntSize(aReadSize.width, 1));
  }

  mGL->fUnmapBuffer(LOCAL_GL_PIXEL_PACK_BUFFER);

  return true;
}

PerUnitTexturePoolOGL::PerUnitTexturePoolOGL(gl::GLContext* aGL)
    : mTextureTarget(0),  // zero is never a valid texture target
      mGL(aGL) {}

PerUnitTexturePoolOGL::~PerUnitTexturePoolOGL() { DestroyTextures(); }

CompositorOGL::CompositorOGL(widget::CompositorWidget* aWidget,
                             int aSurfaceWidth, int aSurfaceHeight,
                             bool aUseExternalSurfaceSize)
    : Compositor(aWidget),
      mWidgetSize(-1, -1),
      mSurfaceSize(aSurfaceWidth, aSurfaceHeight),
      mFBOTextureTarget(0),
      mWindowRenderTarget(nullptr),
      mQuadVBO(0),
      mTriangleVBO(0),
      mPreviousFrameDoneSync(nullptr),
      mThisFrameDoneSync(nullptr),
      mHasBGRA(0),
      mUseExternalSurfaceSize(aUseExternalSurfaceSize),
      mFrameInProgress(false),
      mDestroyed(false),
      mViewportSize(0, 0) {
  if (aWidget->GetNativeLayerRoot()) {
    // We can only render into native layers, our GLContext won't have a usable
    // default framebuffer.
    mCanRenderToDefaultFramebuffer = false;
  }
  MOZ_COUNT_CTOR(CompositorOGL);
}

CompositorOGL::~CompositorOGL() { MOZ_COUNT_DTOR(CompositorOGL); }

already_AddRefed<mozilla::gl::GLContext> CompositorOGL::CreateContext() {
  RefPtr<GLContext> context;

  // Used by mock widget to create an offscreen context
  nsIWidget* widget = mWidget->RealWidget();
  void* widgetOpenGLContext =
      widget ? widget->GetNativeData(NS_NATIVE_OPENGL_CONTEXT) : nullptr;
  if (widgetOpenGLContext) {
    GLContext* alreadyRefed = reinterpret_cast<GLContext*>(widgetOpenGLContext);
    return already_AddRefed<GLContext>(alreadyRefed);
  }

#ifdef XP_WIN
  if (gfxEnv::MOZ_LAYERS_PREFER_EGL()) {
    printf_stderr("Trying GL layers...\n");
    context = gl::GLContextProviderEGL::CreateForCompositorWidget(
        mWidget, /* aHardwareWebRender */ false, /* aForceAccelerated */ false);
  }
#endif

  // Allow to create offscreen GL context for main Layer Manager
  if (!context && gfxEnv::MOZ_LAYERS_PREFER_OFFSCREEN()) {
    nsCString discardFailureId;
    context = GLContextProvider::CreateHeadless(
        {CreateContextFlags::REQUIRE_COMPAT_PROFILE}, &discardFailureId);
    if (!context->CreateOffscreenDefaultFb(mSurfaceSize)) {
      context = nullptr;
    }
  }

  if (!context) {
    context = gl::GLContextProvider::CreateForCompositorWidget(
        mWidget,
        /* aHardwareWebRender */ false,
        gfxVars::RequiresAcceleratedGLContextForCompositorOGL());
  }

  if (!context) {
    NS_WARNING("Failed to create CompositorOGL context");
  }

  return context.forget();
}

void CompositorOGL::Destroy() {
  Compositor::Destroy();

  if (mTexturePool) {
    mTexturePool->Clear();
    mTexturePool = nullptr;
  }

  if (!mDestroyed) {
    mDestroyed = true;
    CleanupResources();
  }
}

void CompositorOGL::CleanupResources() {
  if (!mGLContext) return;

  if (mSurfacePoolHandle) {
    mSurfacePoolHandle->Pool()->DestroyGLResourcesForContext(mGLContext);
    mSurfacePoolHandle = nullptr;
  }

  RefPtr<GLContext> ctx = mGLContext->GetSharedContext();
  if (!ctx) {
    ctx = mGLContext;
  }

  if (!ctx->MakeCurrent()) {
    // Leak resources!
    mQuadVBO = 0;
    mTriangleVBO = 0;
    mPreviousFrameDoneSync = nullptr;
    mThisFrameDoneSync = nullptr;
    mProgramsHolder = nullptr;
    mGLContext = nullptr;
    mNativeLayersReferenceRT = nullptr;
    mFullWindowRenderTarget = nullptr;
    return;
  }

  mProgramsHolder = nullptr;
  mNativeLayersReferenceRT = nullptr;
  mFullWindowRenderTarget = nullptr;

#ifdef MOZ_WIDGET_GTK
  // TextureSources might hold RefPtr<gl::GLContext>.
  // All of them needs to be released to destroy GLContext.
  // GLContextGLX has to be destroyed before related gtk window is destroyed.
  for (auto textureSource : mRegisteredTextureSources) {
    textureSource->DeallocateDeviceData();
  }
  mRegisteredTextureSources.clear();
#endif

  ctx->fBindFramebuffer(LOCAL_GL_FRAMEBUFFER, 0);

  if (mQuadVBO) {
    ctx->fDeleteBuffers(1, &mQuadVBO);
    mQuadVBO = 0;
  }

  if (mTriangleVBO) {
    ctx->fDeleteBuffers(1, &mTriangleVBO);
    mTriangleVBO = 0;
  }

  mGLContext->MakeCurrent();

  if (mPreviousFrameDoneSync) {
    mGLContext->fDeleteSync(mPreviousFrameDoneSync);
    mPreviousFrameDoneSync = nullptr;
  }

  if (mThisFrameDoneSync) {
    mGLContext->fDeleteSync(mThisFrameDoneSync);
    mThisFrameDoneSync = nullptr;
  }

  if (mOwnsGLContext) {
    // On the main thread the Widget will be destroyed soon and calling
    // MakeCurrent after that could cause a crash (at least with GLX, see bug
    // 1059793), unless context is marked as destroyed. There may be some
    // textures still alive that will try to call MakeCurrent on the context so
    // let's make sure it is marked destroyed now.
    mGLContext->MarkDestroyed();
  }

  mGLContext = nullptr;
}

bool CompositorOGL::Initialize(GLContext* aGLContext,
                               RefPtr<ShaderProgramOGLsHolder> aProgramsHolder,
                               nsCString* const out_failureReason) {
  MOZ_ASSERT(!mDestroyed);
  MOZ_ASSERT(!mGLContext);

  mGLContext = aGLContext;
  mProgramsHolder = aProgramsHolder;
  mOwnsGLContext = false;

  return Initialize(out_failureReason);
}

bool CompositorOGL::Initialize(nsCString* const out_failureReason) {
  ScopedGfxFeatureReporter reporter("GL Layers");

  // Do not allow double initialization
  MOZ_ASSERT(mGLContext == nullptr || !mOwnsGLContext,
             "Don't reinitialize CompositorOGL");

  if (!mGLContext) {
    MOZ_ASSERT(mOwnsGLContext);
    mGLContext = CreateContext();
  }

#ifdef MOZ_WIDGET_ANDROID
  if (!mGLContext) {
    *out_failureReason = "FEATURE_FAILURE_OPENGL_NO_ANDROID_CONTEXT";
    MOZ_CRASH("We need a context on Android");
  }
#endif

  if (!mGLContext) {
    *out_failureReason = "FEATURE_FAILURE_OPENGL_CREATE_CONTEXT";
    return false;
  }

  if (!mProgramsHolder) {
    mProgramsHolder = new ShaderProgramOGLsHolder(mGLContext);
  }

  MakeCurrent();

  mHasBGRA = mGLContext->IsExtensionSupported(
                 gl::GLContext::EXT_texture_format_BGRA8888) ||
             mGLContext->IsExtensionSupported(gl::GLContext::EXT_bgra);

  mGLContext->fBlendFuncSeparate(LOCAL_GL_ONE, LOCAL_GL_ONE_MINUS_SRC_ALPHA,
                                 LOCAL_GL_ONE, LOCAL_GL_ONE_MINUS_SRC_ALPHA);
  mGLContext->fEnable(LOCAL_GL_BLEND);

  // initialise a common shader to check that we can actually compile a shader
  RefPtr<EffectNV12> effect =
      new EffectNV12(nullptr, YUVColorSpace::BT601, ColorRange::LIMITED,
                     ColorDepth::COLOR_8, SamplingFilter::GOOD);
  ShaderConfigOGL config = GetShaderConfigFor(effect);
  if (!GetShaderProgramFor(config)) {
    *out_failureReason = "FEATURE_FAILURE_OPENGL_COMPILE_SHADER";
    return false;
  }

  if (mGLContext->WorkAroundDriverBugs()) {
    /**
     * We'll test the ability here to bind NPOT textures to a framebuffer, if
     * this fails we'll try ARB_texture_rectangle.
     */

    GLenum textureTargets[] = {LOCAL_GL_TEXTURE_2D, LOCAL_GL_NONE};

    if (!mGLContext->IsGLES()) {
      // No TEXTURE_RECTANGLE_ARB available on ES2
      textureTargets[1] = LOCAL_GL_TEXTURE_RECTANGLE_ARB;
    }

    mFBOTextureTarget = LOCAL_GL_NONE;

    GLuint testFBO = 0;
    mGLContext->fGenFramebuffers(1, &testFBO);
    GLuint testTexture = 0;

    for (uint32_t i = 0; i < ArrayLength(textureTargets); i++) {
      GLenum target = textureTargets[i];
      if (!target) continue;

      mGLContext->fGenTextures(1, &testTexture);
      mGLContext->fBindTexture(target, testTexture);
      mGLContext->fTexParameteri(target, LOCAL_GL_TEXTURE_MIN_FILTER,
                                 LOCAL_GL_NEAREST);
      mGLContext->fTexParameteri(target, LOCAL_GL_TEXTURE_MAG_FILTER,
                                 LOCAL_GL_NEAREST);
      mGLContext->fTexImage2D(
          target, 0, LOCAL_GL_RGBA, 5, 3, /* sufficiently NPOT */
          0, LOCAL_GL_RGBA, LOCAL_GL_UNSIGNED_BYTE, nullptr);

      // unbind this texture, in preparation for binding it to the FBO
      mGLContext->fBindTexture(target, 0);

      mGLContext->fBindFramebuffer(LOCAL_GL_FRAMEBUFFER, testFBO);
      mGLContext->fFramebufferTexture2D(LOCAL_GL_FRAMEBUFFER,
                                        LOCAL_GL_COLOR_ATTACHMENT0, target,
                                        testTexture, 0);

      if (mGLContext->fCheckFramebufferStatus(LOCAL_GL_FRAMEBUFFER) ==
          LOCAL_GL_FRAMEBUFFER_COMPLETE) {
        mFBOTextureTarget = target;
        mGLContext->fDeleteTextures(1, &testTexture);
        break;
      }

      mGLContext->fDeleteTextures(1, &testTexture);
    }

    if (testFBO) {
      mGLContext->fDeleteFramebuffers(1, &testFBO);
    }

    if (mFBOTextureTarget == LOCAL_GL_NONE) {
      /* Unable to find a texture target that works with FBOs and NPOT textures
       */
      *out_failureReason = "FEATURE_FAILURE_OPENGL_NO_TEXTURE_TARGET";
      return false;
    }
  } else {
    // not trying to work around driver bugs, so TEXTURE_2D should just work
    mFBOTextureTarget = LOCAL_GL_TEXTURE_2D;
  }

  // back to default framebuffer, to avoid confusion
  mGLContext->fBindFramebuffer(LOCAL_GL_FRAMEBUFFER, 0);

  if (mFBOTextureTarget == LOCAL_GL_TEXTURE_RECTANGLE_ARB) {
    /* If we're using TEXTURE_RECTANGLE, then we must have the ARB
     * extension -- the EXT variant does not provide support for
     * texture rectangle access inside GLSL (sampler2DRect,
     * texture2DRect).
     */
    if (!mGLContext->IsExtensionSupported(
            gl::GLContext::ARB_texture_rectangle)) {
      *out_failureReason = "FEATURE_FAILURE_OPENGL_ARB_EXT";
      return false;
    }
  }

  // Create a VBO for triangle vertices.
  mGLContext->fGenBuffers(1, &mTriangleVBO);

  /* Create a simple quad VBO */
  mGLContext->fGenBuffers(1, &mQuadVBO);

  // 4 quads, with the number of the quad (vertexID) encoded in w.
  GLfloat vertices[] = {
      0.0f, 0.0f, 0.0f, 0.0f, 1.0f, 0.0f, 0.0f, 0.0f, 0.0f, 1.0f, 0.0f, 0.0f,
      1.0f, 0.0f, 0.0f, 0.0f, 0.0f, 1.0f, 0.0f, 0.0f, 1.0f, 1.0f, 0.0f, 0.0f,

      0.0f, 0.0f, 0.0f, 1.0f, 1.0f, 0.0f, 0.0f, 1.0f, 0.0f, 1.0f, 0.0f, 1.0f,
      1.0f, 0.0f, 0.0f, 1.0f, 0.0f, 1.0f, 0.0f, 1.0f, 1.0f, 1.0f, 0.0f, 1.0f,

      0.0f, 0.0f, 0.0f, 2.0f, 1.0f, 0.0f, 0.0f, 2.0f, 0.0f, 1.0f, 0.0f, 2.0f,
      1.0f, 0.0f, 0.0f, 2.0f, 0.0f, 1.0f, 0.0f, 2.0f, 1.0f, 1.0f, 0.0f, 2.0f,

      0.0f, 0.0f, 0.0f, 3.0f, 1.0f, 0.0f, 0.0f, 3.0f, 0.0f, 1.0f, 0.0f, 3.0f,
      1.0f, 0.0f, 0.0f, 3.0f, 0.0f, 1.0f, 0.0f, 3.0f, 1.0f, 1.0f, 0.0f, 3.0f,
  };
  HeapCopyOfStackArray<GLfloat> verticesOnHeap(vertices);

  mGLContext->fBindBuffer(LOCAL_GL_ARRAY_BUFFER, mQuadVBO);
  mGLContext->fBufferData(LOCAL_GL_ARRAY_BUFFER, verticesOnHeap.ByteLength(),
                          verticesOnHeap.Data(), LOCAL_GL_STATIC_DRAW);
  mGLContext->fBindBuffer(LOCAL_GL_ARRAY_BUFFER, 0);

  nsCOMPtr<nsIConsoleService> console(
      do_GetService(NS_CONSOLESERVICE_CONTRACTID));

  if (console) {
    nsString msg;
    msg += nsLiteralString(
        u"OpenGL compositor Initialized Succesfully.\nVersion: ");
    msg += NS_ConvertUTF8toUTF16(nsDependentCString(
        (const char*)mGLContext->fGetString(LOCAL_GL_VERSION)));
    msg += u"\nVendor: "_ns;
    msg += NS_ConvertUTF8toUTF16(nsDependentCString(
        (const char*)mGLContext->fGetString(LOCAL_GL_VENDOR)));
    msg += u"\nRenderer: "_ns;
    msg += NS_ConvertUTF8toUTF16(nsDependentCString(
        (const char*)mGLContext->fGetString(LOCAL_GL_RENDERER)));
    msg += u"\nFBO Texture Target: "_ns;
    if (mFBOTextureTarget == LOCAL_GL_TEXTURE_2D)
      msg += u"TEXTURE_2D"_ns;
    else
      msg += u"TEXTURE_RECTANGLE"_ns;
    console->LogStringMessage(msg.get());
  }

  reporter.SetSuccessful();

  return true;
}

/*
 * Returns a size that is equal to, or larger than and closest to,
 * aSize where both width and height are powers of two.
 * If the OpenGL setup is capable of using non-POT textures,
 * then it will just return aSize.
 */
static IntSize CalculatePOTSize(const IntSize& aSize, GLContext* gl) {
  if (CanUploadNonPowerOfTwo(gl)) return aSize;

  return IntSize(RoundUpPow2(aSize.width), RoundUpPow2(aSize.height));
}

gfx::Rect CompositorOGL::GetTextureCoordinates(gfx::Rect textureRect,
                                               TextureSource* aTexture) {
  // If the OpenGL setup does not support non-power-of-two textures then the
  // texture's width and height will have been increased to the next
  // power-of-two (unless already a power of two). In that case we must scale
  // the texture coordinates to account for that.
  if (!CanUploadNonPowerOfTwo(mGLContext)) {
    const IntSize& textureSize = aTexture->GetSize();
    const IntSize potSize = CalculatePOTSize(textureSize, mGLContext);
    if (potSize != textureSize) {
      const float xScale = (float)textureSize.width / (float)potSize.width;
      const float yScale = (float)textureSize.height / (float)potSize.height;
      textureRect.Scale(xScale, yScale);
    }
  }

  return textureRect;
}

void CompositorOGL::PrepareViewport(CompositingRenderTargetOGL* aRenderTarget) {
  MOZ_ASSERT(aRenderTarget);
  // Logical surface size.
  const gfx::IntSize& size = aRenderTarget->GetSize();
  // Physical surface size.
  const gfx::IntSize& phySize = aRenderTarget->GetPhysicalSize();

  // Set the viewport correctly.
  mGLContext->fViewport(mSurfaceOrigin.x, mSurfaceOrigin.y, phySize.width,
                        phySize.height);

  mViewportSize = size;

  if (!aRenderTarget->HasComplexProjection()) {
    // We flip the view matrix around so that everything is right-side up; we're
    // drawing directly into the window's back buffer, so this keeps things
    // looking correct.
    // XXX: We keep track of whether the window size changed, so we could skip
    // this update if it hadn't changed since the last call.

    // Matrix to transform (0, 0, aWidth, aHeight) to viewport space (-1.0, 1.0,
    // 2, 2) and flip the contents.
    Matrix viewMatrix;
    viewMatrix.PreTranslate(-1.0, 1.0);
    viewMatrix.PreScale(2.0f / float(size.width), 2.0f / float(size.height));
    viewMatrix.PreScale(1.0f, -1.0f);

    MOZ_ASSERT(mCurrentRenderTarget, "No destination");

    Matrix4x4 matrix3d = Matrix4x4::From2D(viewMatrix);
    matrix3d._33 = 0.0f;
    mProjMatrix = matrix3d;
    mGLContext->fDepthRange(0.0f, 1.0f);
  } else {
    bool depthEnable;
    float zNear, zFar;
    aRenderTarget->GetProjection(mProjMatrix, depthEnable, zNear, zFar);
    mGLContext->fDepthRange(zNear, zFar);
  }
}

already_AddRefed<CompositingRenderTarget> CompositorOGL::CreateRenderTarget(
    const IntRect& aRect, SurfaceInitMode aInit) {
  MOZ_ASSERT(!aRect.IsZeroArea(),
             "Trying to create a render target of invalid size");

  if (aRect.IsZeroArea()) {
    return nullptr;
  }

  if (!gl()) {
    // CompositingRenderTargetOGL does not work without a gl context.
    return nullptr;
  }

  GLuint tex = 0;
  GLuint fbo = 0;
  IntRect rect = aRect;
  IntSize fboSize;
  CreateFBOWithTexture(rect, false, 0, &fbo, &tex, &fboSize);
  return CompositingRenderTargetOGL::CreateForNewFBOAndTakeOwnership(
      this, tex, fbo, aRect, aRect.TopLeft(), aRect.Size(), mFBOTextureTarget,
      aInit);
}

void CompositorOGL::SetRenderTarget(CompositingRenderTarget* aSurface) {
  MOZ_ASSERT(aSurface);
  CompositingRenderTargetOGL* surface =
      static_cast<CompositingRenderTargetOGL*>(aSurface);
  if (mCurrentRenderTarget != surface) {
    mCurrentRenderTarget = surface;
    surface->BindRenderTarget();
  }

  PrepareViewport(mCurrentRenderTarget);
}

already_AddRefed<CompositingRenderTarget>
CompositorOGL::GetCurrentRenderTarget() const {
  return do_AddRef(mCurrentRenderTarget);
}

already_AddRefed<CompositingRenderTarget> CompositorOGL::GetWindowRenderTarget()
    const {
  return do_AddRef(mWindowRenderTarget);
}

already_AddRefed<AsyncReadbackBuffer> CompositorOGL::CreateAsyncReadbackBuffer(
    const IntSize& aSize) {
  return MakeAndAddRef<AsyncReadbackBufferOGL>(mGLContext, aSize);
}

bool CompositorOGL::ReadbackRenderTarget(CompositingRenderTarget* aSource,
                                         AsyncReadbackBuffer* aDest) {
  IntSize size = aSource->GetSize();
  MOZ_RELEASE_ASSERT(aDest->GetSize() == size);

  RefPtr<CompositingRenderTarget> previousTarget = GetCurrentRenderTarget();
  if (previousTarget != aSource) {
    SetRenderTarget(aSource);
  }

  ScopedPackState scopedPackState(mGLContext);
  static_cast<AsyncReadbackBufferOGL*>(aDest)->Bind();

  mGLContext->fReadPixels(0, 0, size.width, size.height, LOCAL_GL_RGBA,
                          LOCAL_GL_UNSIGNED_BYTE, 0);

  if (previousTarget != aSource) {
    SetRenderTarget(previousTarget);
  }
  return true;
}

bool CompositorOGL::BlitRenderTarget(CompositingRenderTarget* aSource,
                                     const gfx::IntSize& aSourceSize,
                                     const gfx::IntSize& aDestSize) {
  if (!mGLContext->IsSupported(GLFeature::framebuffer_blit)) {
    return false;
  }
  CompositingRenderTargetOGL* source =
      static_cast<CompositingRenderTargetOGL*>(aSource);
  GLuint srcFBO = source->GetFBO();
  GLuint destFBO = mCurrentRenderTarget->GetFBO();
  mGLContext->BlitHelper()->BlitFramebufferToFramebuffer(
      srcFBO, destFBO, IntRect(IntPoint(), aSourceSize),
      IntRect(IntPoint(), aDestSize), LOCAL_GL_LINEAR);
  return true;
}

static GLenum GetFrameBufferInternalFormat(
    GLContext* gl, GLuint aFrameBuffer,
    mozilla::widget::CompositorWidget* aWidget) {
  if (aFrameBuffer == 0) {  // default framebuffer
    return aWidget->GetGLFrameBufferFormat();
  }
  return LOCAL_GL_RGBA;
}

Maybe<IntRect> CompositorOGL::BeginFrameForWindow(
    const nsIntRegion& aInvalidRegion, const Maybe<IntRect>& aClipRect,
    const IntRect& aRenderBounds, const nsIntRegion& aOpaqueRegion) {
  MOZ_RELEASE_ASSERT(!mTarget, "mTarget not cleared properly");
  return BeginFrame(aInvalidRegion, aClipRect, aRenderBounds, aOpaqueRegion);
}

Maybe<IntRect> CompositorOGL::BeginFrame(const nsIntRegion& aInvalidRegion,
                                         const Maybe<IntRect>& aClipRect,
                                         const IntRect& aRenderBounds,
                                         const nsIntRegion& aOpaqueRegion) {
  AUTO_PROFILER_LABEL("CompositorOGL::BeginFrame", GRAPHICS);

  MOZ_ASSERT(!mFrameInProgress,
             "frame still in progress (should have called EndFrame");

  IntRect rect;
  if (mUseExternalSurfaceSize) {
    rect = IntRect(IntPoint(), mSurfaceSize);
  } else {
    rect = aRenderBounds;
  }

  // We can't draw anything to something with no area
  // so just return
  if (rect.IsZeroArea()) {
    return Nothing();
  }

  // If the widget size changed, we have to force a MakeCurrent
  // to make sure that GL sees the updated widget size.
  if (mWidgetSize.ToUnknownSize() != rect.Size()) {
    MakeCurrent(ForceMakeCurrent);

    mWidgetSize = LayoutDeviceIntSize::FromUnknownSize(rect.Size());
#ifdef MOZ_WAYLAND
    if (mWidget && mWidget->AsGTK()) {
      mWidget->AsGTK()->SetEGLNativeWindowSize(mWidgetSize);
    }
#endif
  } else {
    MakeCurrent();
  }

#ifdef MOZ_WIDGET_ANDROID
  java::GeckoSurfaceTexture::DestroyUnused((int64_t)mGLContext.get());
  mGLContext->MakeCurrent();  // DestroyUnused can change the current context!
#endif

  // Default blend function implements "OVER"
  mGLContext->fBlendFuncSeparate(LOCAL_GL_ONE, LOCAL_GL_ONE_MINUS_SRC_ALPHA,
                                 LOCAL_GL_ONE, LOCAL_GL_ONE_MINUS_SRC_ALPHA);
  mGLContext->fEnable(LOCAL_GL_BLEND);

  RefPtr<CompositingRenderTarget> rt;
  if (mCanRenderToDefaultFramebuffer) {
    rt = CompositingRenderTargetOGL::CreateForWindow(this, rect.Size());
  } else if (mTarget) {
    rt = CreateRenderTarget(rect, INIT_MODE_CLEAR);
  } else {
    MOZ_CRASH("Unexpected call");
  }

  if (!rt) {
    return Nothing();
  }

  // We're about to actually draw a frame.
  mFrameInProgress = true;

  SetRenderTarget(rt);
  mWindowRenderTarget = mCurrentRenderTarget;

  for (auto iter = aInvalidRegion.RectIter(); !iter.Done(); iter.Next()) {
    const IntRect& r = iter.Get();
    mCurrentFrameInvalidRegion.OrWith(
        IntRect(r.X(), FlipY(r.YMost()), r.Width(), r.Height()));
  }
  // Check to see if there is any transparent dirty region that would require
  // clearing. If not, just invalidate the framebuffer if supported.
  // TODO: Currently we initialize the clear region to the widget bounds as
  // SwapBuffers will update the entire framebuffer. On platforms that support
  // damage regions, we could initialize this to mCurrentFrameInvalidRegion.
  IntRegion regionToClear(rect);
  regionToClear.SubOut(aOpaqueRegion);
  GLbitfield clearBits = LOCAL_GL_DEPTH_BUFFER_BIT;
  if (regionToClear.IsEmpty() &&
      mGLContext->IsSupported(GLFeature::invalidate_framebuffer)) {
    GLenum attachments[] = {LOCAL_GL_COLOR};
    mGLContext->fInvalidateFramebuffer(
        LOCAL_GL_FRAMEBUFFER, MOZ_ARRAY_LENGTH(attachments), attachments);
  } else {
    clearBits |= LOCAL_GL_COLOR_BUFFER_BIT;
  }

#if defined(MOZ_WIDGET_ANDROID)
  if ((mSurfaceOrigin.x > 0) || (mSurfaceOrigin.y > 0)) {
    mGLContext->fClearColor(
        StaticPrefs::gfx_compositor_override_clear_color_r(),
        StaticPrefs::gfx_compositor_override_clear_color_g(),
        StaticPrefs::gfx_compositor_override_clear_color_b(),
        StaticPrefs::gfx_compositor_override_clear_color_a());
  } else {
    mGLContext->fClearColor(mClearColor.r, mClearColor.g, mClearColor.b,
                            mClearColor.a);
  }
#else
  mGLContext->fClearColor(mClearColor.r, mClearColor.g, mClearColor.b,
                          mClearColor.a);
#endif  // defined(MOZ_WIDGET_ANDROID)
  mGLContext->fClear(clearBits);

  return Some(rect);
}

void CompositorOGL::CreateFBOWithTexture(const gfx::IntRect& aRect,
                                         bool aCopyFromSource,
                                         GLuint aSourceFrameBuffer,
                                         GLuint* aFBO, GLuint* aTexture,
                                         gfx::IntSize* aAllocSize) {
  *aTexture =
      CreateTexture(aRect, aCopyFromSource, aSourceFrameBuffer, aAllocSize);
  mGLContext->fGenFramebuffers(1, aFBO);
}

// Should be called after calls to fReadPixels or fCopyTexImage2D, and other
// GL read calls.
static void WorkAroundAppleIntelHD3000GraphicsGLDriverBug(GLContext* aGL) {
#ifdef XP_MACOSX
  if (aGL->WorkAroundDriverBugs() &&
      aGL->Renderer() == GLRenderer::IntelHD3000) {
    // Work around a bug in the Apple Intel HD Graphics 3000 driver (bug
    // 1586627, filed with Apple as FB7379358). This bug has been found present
    // on 10.9.3 and on 10.13.6, so it likely affects all shipped versions of
    // this driver. (macOS 10.14 does not support this GPU.)
    // The bug manifests as follows: Reading from a framebuffer puts that
    // framebuffer into a state such that deleting that framebuffer can break
    // other framebuffers in certain cases. More specifically, if you have two
    // framebuffers A and B, the following sequence of events breaks subsequent
    // drawing to B:
    //  1. A becomes "most recently read-from framebuffer".
    //  2. B is drawn to.
    //  3. A is deleted, and other GL state (such as GL_SCISSOR enabled state)
    //     is touched.
    //  4. B is drawn to again.
    // Now all draws to framebuffer B, including the draw from step 4, will
    // render at the wrong position and upside down.
    //
    // When AfterGLReadCall() is called, the currently bound framebuffer is the
    // framebuffer that has been read from most recently. So in the presence of
    // this bug, deleting this framebuffer has now become dangerous. We work
    // around the bug by creating a new short-lived framebuffer, making that new
    // framebuffer the most recently read-from framebuffer (using
    // glCopyTexImage2D), and then deleting it under controlled circumstances.
    // This deletion is not affected by the bug because our deletion call is not
    // interleaved with draw calls to another framebuffer and a touching of the
    // GL scissor enabled state.

    ScopedTexture texForReading(aGL);
    {
      // Initialize a 1x1 texture.
      ScopedBindTexture autoBindTexForReading(aGL, texForReading);
      aGL->fTexImage2D(LOCAL_GL_TEXTURE_2D, 0, LOCAL_GL_RGBA, 1, 1, 0,
                       LOCAL_GL_RGBA, LOCAL_GL_UNSIGNED_BYTE, nullptr);
      aGL->fTexParameteri(LOCAL_GL_TEXTURE_2D, LOCAL_GL_TEXTURE_MIN_FILTER,
                          LOCAL_GL_LINEAR);
      aGL->fTexParameteri(LOCAL_GL_TEXTURE_2D, LOCAL_GL_TEXTURE_MAG_FILTER,
                          LOCAL_GL_LINEAR);
    }
    // Make a framebuffer around the texture.
    ScopedFramebufferForTexture autoFBForReading(aGL, texForReading);
    if (autoFBForReading.IsComplete()) {
      // "Read" from the framebuffer, by initializing a new texture using
      // glCopyTexImage2D. This flips the bad bit on autoFBForReading.FB().
      ScopedBindFramebuffer autoFB(aGL, autoFBForReading.FB());
      ScopedTexture texReadingDest(aGL);
      ScopedBindTexture autoBindTexReadingDest(aGL, texReadingDest);
      aGL->fCopyTexImage2D(LOCAL_GL_TEXTURE_2D, 0, LOCAL_GL_RGBA, 0, 0, 1, 1,
                           0);
    }
    // When autoFBForReading goes out of scope, the "poisoned" framebuffer is
    // deleted, and the bad state seems to go away along with it.
  }
#endif
}

GLuint CompositorOGL::CreateTexture(const IntRect& aRect, bool aCopyFromSource,
                                    GLuint aSourceFrameBuffer,
                                    IntSize* aAllocSize) {
  // we're about to create a framebuffer backed by textures to use as an
  // intermediate surface. What to do if its size (as given by aRect) would
  // exceed the maximum texture size supported by the GL? The present code
  // chooses the compromise of just clamping the framebuffer's size to the max
  // supported size. This gives us a lower resolution rendering of the
  // intermediate surface (children layers). See bug 827170 for a discussion.
  IntRect clampedRect = aRect;
  int32_t maxTexSize = GetMaxTextureSize();
  clampedRect.SetWidth(std::min(clampedRect.Width(), maxTexSize));
  clampedRect.SetHeight(std::min(clampedRect.Height(), maxTexSize));

  auto clampedRectWidth = clampedRect.Width();
  auto clampedRectHeight = clampedRect.Height();

  GLuint tex;

  mGLContext->fActiveTexture(LOCAL_GL_TEXTURE0);
  mGLContext->fGenTextures(1, &tex);
  mGLContext->fBindTexture(mFBOTextureTarget, tex);

  if (aCopyFromSource) {
    GLuint curFBO = mCurrentRenderTarget->GetFBO();
    if (curFBO != aSourceFrameBuffer) {
      mGLContext->fBindFramebuffer(LOCAL_GL_FRAMEBUFFER, aSourceFrameBuffer);
    }

    // We're going to create an RGBA temporary fbo.  But to
    // CopyTexImage() from the current framebuffer, the framebuffer's
    // format has to be compatible with the new texture's.  So we
    // check the format of the framebuffer here and take a slow path
    // if it's incompatible.
    GLenum format =
        GetFrameBufferInternalFormat(gl(), aSourceFrameBuffer, mWidget);

    bool isFormatCompatibleWithRGBA =
        gl()->IsGLES() ? (format == LOCAL_GL_RGBA) : true;

    if (isFormatCompatibleWithRGBA) {
      mGLContext->fCopyTexImage2D(mFBOTextureTarget, 0, LOCAL_GL_RGBA,
                                  clampedRect.X(), FlipY(clampedRect.YMost()),
                                  clampedRectWidth, clampedRectHeight, 0);
      WorkAroundAppleIntelHD3000GraphicsGLDriverBug(mGLContext);
    } else {
      // Curses, incompatible formats.  Take a slow path.

      // RGBA
      size_t bufferSize = clampedRectWidth * clampedRectHeight * 4;
      auto buf = MakeUnique<uint8_t[]>(bufferSize);

      mGLContext->fReadPixels(clampedRect.X(), clampedRect.Y(),
                              clampedRectWidth, clampedRectHeight,
                              LOCAL_GL_RGBA, LOCAL_GL_UNSIGNED_BYTE, buf.get());
      WorkAroundAppleIntelHD3000GraphicsGLDriverBug(mGLContext);
      mGLContext->fTexImage2D(mFBOTextureTarget, 0, LOCAL_GL_RGBA,
                              clampedRectWidth, clampedRectHeight, 0,
                              LOCAL_GL_RGBA, LOCAL_GL_UNSIGNED_BYTE, buf.get());
    }

    GLenum error = mGLContext->fGetError();
    if (error != LOCAL_GL_NO_ERROR) {
      nsAutoCString msg;
      msg.AppendPrintf(
          "Texture initialization failed! -- error 0x%x, Source %d, Source "
          "format %d,  RGBA Compat %d",
          error, aSourceFrameBuffer, format, isFormatCompatibleWithRGBA);
      NS_ERROR(msg.get());
    }
  } else {
    mGLContext->fTexImage2D(mFBOTextureTarget, 0, LOCAL_GL_RGBA,
                            clampedRectWidth, clampedRectHeight, 0,
                            LOCAL_GL_RGBA, LOCAL_GL_UNSIGNED_BYTE, nullptr);
  }
  mGLContext->fTexParameteri(mFBOTextureTarget, LOCAL_GL_TEXTURE_MIN_FILTER,
                             LOCAL_GL_LINEAR);
  mGLContext->fTexParameteri(mFBOTextureTarget, LOCAL_GL_TEXTURE_MAG_FILTER,
                             LOCAL_GL_LINEAR);
  mGLContext->fTexParameteri(mFBOTextureTarget, LOCAL_GL_TEXTURE_WRAP_S,
                             LOCAL_GL_CLAMP_TO_EDGE);
  mGLContext->fTexParameteri(mFBOTextureTarget, LOCAL_GL_TEXTURE_WRAP_T,
                             LOCAL_GL_CLAMP_TO_EDGE);
  mGLContext->fBindTexture(mFBOTextureTarget, 0);

  if (aAllocSize) {
    aAllocSize->width = clampedRectWidth;
    aAllocSize->height = clampedRectHeight;
  }

  return tex;
}

ShaderConfigOGL CompositorOGL::GetShaderConfigFor(Effect* aEffect,
                                                  bool aDEAAEnabled) const {
  ShaderConfigOGL config;

  switch (aEffect->mType) {
    case EffectTypes::YCBCR: {
      config.SetYCbCr(true);
      EffectYCbCr* effectYCbCr = static_cast<EffectYCbCr*>(aEffect);
      config.SetColorMultiplier(
          RescalingFactorForColorDepth(effectYCbCr->mColorDepth));
      config.SetTextureTarget(
          effectYCbCr->mTexture->AsSourceOGL()->GetTextureTarget());
      break;
    }
    case EffectTypes::NV12:
      config.SetNV12(true);
      if (gl()->IsExtensionSupported(gl::GLContext::ARB_texture_rectangle)) {
        config.SetTextureTarget(LOCAL_GL_TEXTURE_RECTANGLE_ARB);
      } else {
        config.SetTextureTarget(LOCAL_GL_TEXTURE_2D);
      }
      break;
    default: {
      MOZ_ASSERT(aEffect->mType == EffectTypes::RGB);
      TexturedEffect* texturedEffect = static_cast<TexturedEffect*>(aEffect);
      TextureSourceOGL* source = texturedEffect->mTexture->AsSourceOGL();
      MOZ_ASSERT_IF(
          source->GetTextureTarget() == LOCAL_GL_TEXTURE_EXTERNAL,
          source->GetFormat() == gfx::SurfaceFormat::R8G8B8A8 ||
              source->GetFormat() == gfx::SurfaceFormat::R8G8B8X8 ||
              source->GetFormat() == gfx::SurfaceFormat::B8G8R8A8 ||
              source->GetFormat() == gfx::SurfaceFormat::B8G8R8X8 ||
              source->GetFormat() == gfx::SurfaceFormat::R5G6B5_UINT16);
      MOZ_ASSERT_IF(
          source->GetTextureTarget() == LOCAL_GL_TEXTURE_RECTANGLE_ARB,
          source->GetFormat() == gfx::SurfaceFormat::R8G8B8A8 ||
              source->GetFormat() == gfx::SurfaceFormat::R8G8B8X8 ||
              source->GetFormat() == gfx::SurfaceFormat::R5G6B5_UINT16 ||
              source->GetFormat() == gfx::SurfaceFormat::YUV422);
      config = ShaderConfigFromTargetAndFormat(source->GetTextureTarget(),
                                               source->GetFormat());
      if (!texturedEffect->mPremultiplied) {
        config.SetNoPremultipliedAlpha();
      }
      break;
    }
  }
  config.SetDEAA(aDEAAEnabled);
  return config;
}

ShaderProgramOGL* CompositorOGL::GetShaderProgramFor(
    const ShaderConfigOGL& aConfig) {
  ShaderProgramOGL* shader = mProgramsHolder->GetShaderProgramFor(aConfig);
  return shader;
}

void CompositorOGL::ResetProgram() { mProgramsHolder->ResetCurrentProgram(); }

static bool SetBlendMode(GLContext* aGL, gfx::CompositionOp aBlendMode,
                         bool aIsPremultiplied = true) {
  if (BlendOpIsMixBlendMode(aBlendMode)) {
    // Mix-blend modes require an extra step (or more) that cannot be expressed
    // in the fixed-function blending capabilities of opengl. We handle them
    // separately in shaders, and the shaders assume we will use our default
    // blend function for compositing (premultiplied OP_OVER).
    return false;
  }
  if (aBlendMode == gfx::CompositionOp::OP_OVER && aIsPremultiplied) {
    return false;
  }

  GLenum srcBlend;
  GLenum dstBlend;
  GLenum srcAlphaBlend = LOCAL_GL_ONE;
  GLenum dstAlphaBlend = LOCAL_GL_ONE_MINUS_SRC_ALPHA;

  switch (aBlendMode) {
    case gfx::CompositionOp::OP_OVER:
      MOZ_ASSERT(!aIsPremultiplied);
      srcBlend = LOCAL_GL_SRC_ALPHA;
      dstBlend = LOCAL_GL_ONE_MINUS_SRC_ALPHA;
      break;
    case gfx::CompositionOp::OP_SOURCE:
      srcBlend = aIsPremultiplied ? LOCAL_GL_ONE : LOCAL_GL_SRC_ALPHA;
      dstBlend = LOCAL_GL_ZERO;
      srcAlphaBlend = LOCAL_GL_ONE;
      dstAlphaBlend = LOCAL_GL_ZERO;
      break;
    default:
      MOZ_ASSERT_UNREACHABLE("Unsupported blend mode!");
      return false;
  }

  aGL->fBlendFuncSeparate(srcBlend, dstBlend, srcAlphaBlend, dstAlphaBlend);
  return true;
}

gfx::Point3D CompositorOGL::GetLineCoefficients(const gfx::Point& aPoint1,
                                                const gfx::Point& aPoint2) {
  // Return standard coefficients for a line between aPoint1 and aPoint2
  // for standard line equation:
  //
  // Ax + By + C = 0
  //
  // A = (p1.y – p2.y)
  // B = (p2.x – p1.x)
  // C = (p1.x * p2.y) – (p2.x * p1.y)

  gfx::Point3D coeffecients;
  coeffecients.x = aPoint1.y - aPoint2.y;
  coeffecients.y = aPoint2.x - aPoint1.x;
  coeffecients.z =
      aPoint1.x.value * aPoint2.y.value - aPoint2.x.value * aPoint1.y.value;

  coeffecients *= 1.0f / sqrtf(coeffecients.x * coeffecients.x +
                               coeffecients.y * coeffecients.y);

  // Offset outwards by 0.5 pixel as the edge is considered to be 1 pixel
  // wide and included within the interior of the polygon
  coeffecients.z += 0.5f;

  return coeffecients;
}

void CompositorOGL::DrawQuad(const Rect& aRect, const IntRect& aClipRect,
                             const EffectChain& aEffectChain, Float aOpacity,
                             const gfx::Matrix4x4& aTransform,
                             const gfx::Rect& aVisibleRect) {
  AUTO_PROFILER_LABEL("CompositorOGL::DrawQuad", GRAPHICS);

  DrawGeometry(aRect, aRect, aClipRect, aEffectChain, aOpacity, aTransform,
               aVisibleRect);
}

template <typename Geometry>
void CompositorOGL::DrawGeometry(const Geometry& aGeometry,
                                 const gfx::Rect& aRect,
                                 const gfx::IntRect& aClipRect,
                                 const EffectChain& aEffectChain,
                                 gfx::Float aOpacity,
                                 const gfx::Matrix4x4& aTransform,
                                 const gfx::Rect& aVisibleRect) {
  MOZ_ASSERT(mFrameInProgress, "frame not started");
  MOZ_ASSERT(mCurrentRenderTarget, "No destination");

  MakeCurrent();

  // Convert aClipRect into render target space, and intersect it with the
  // render target's clip.
  IntRect clipRect = aClipRect + mCurrentRenderTarget->GetClipSpaceOrigin();
  if (Maybe<IntRect> rtClip = mCurrentRenderTarget->GetClipRect()) {
    clipRect = clipRect.Intersect(*rtClip);
  }

  Rect destRect = aTransform.TransformAndClipBounds(
      aRect, Rect(mCurrentRenderTarget->GetRect().Intersect(clipRect)));
  if (destRect.IsEmpty()) {
    return;
  }

  // Move clipRect into device space.
  IntPoint offset = mCurrentRenderTarget->GetOrigin();
  clipRect -= offset;

  if (!mTarget && mCurrentRenderTarget->IsWindow()) {
    clipRect.MoveBy(mSurfaceOrigin.x, -mSurfaceOrigin.y);
  }

  ScopedGLState scopedScissorTestState(mGLContext, LOCAL_GL_SCISSOR_TEST, true);
  ScopedScissorRect autoScissorRect(mGLContext, clipRect.X(),
                                    FlipY(clipRect.Y() + clipRect.Height()),
                                    clipRect.Width(), clipRect.Height());

  // Only apply DEAA to quads that have been transformed such that aliasing
  // could be visible
  bool bEnableAA = StaticPrefs::layers_deaa_enabled() &&
                   !aTransform.Is2DIntegerTranslation();

  ShaderConfigOGL config =
      GetShaderConfigFor(aEffectChain.mPrimaryEffect, bEnableAA);

  config.SetOpacity(aOpacity != 1.f);
  ApplyPrimitiveConfig(config, aGeometry);

  ShaderProgramOGL* program = mProgramsHolder->ActivateProgram(config);
  if (!program) {
    return;
  }
  program->SetProjectionMatrix(mProjMatrix);
  program->SetLayerTransform(aTransform);
  program->SetRenderOffset(offset.x, offset.y);

  if (aOpacity != 1.f) program->SetLayerOpacity(aOpacity);

  if (config.mFeatures & ENABLE_TEXTURE_RECT) {
    TextureSourceOGL* source = nullptr;
    TexturedEffect* texturedEffect =
        static_cast<TexturedEffect*>(aEffectChain.mPrimaryEffect.get());
    source = texturedEffect->mTexture->AsSourceOGL();
    // This is used by IOSurface that use 0,0...w,h coordinate rather then
    // 0,0..1,1.
    program->SetTexCoordMultiplier(source->GetSize().width,
                                   source->GetSize().height);
  }

  // XXX kip - These calculations could be performed once per layer rather than
  //           for every tile.  This might belong in Compositor.cpp once DEAA
  //           is implemented for DirectX.
  if (bEnableAA) {
    // Calculate the transformed vertices of aVisibleRect in screen space
    // pixels, mirroring the calculations in the vertex shader
    Matrix4x4 flatTransform = aTransform;
    flatTransform.PostTranslate(-offset.x, -offset.y, 0.0f);
    flatTransform *= mProjMatrix;

    Rect viewportClip = Rect(-1.0f, -1.0f, 2.0f, 2.0f);
    size_t edgeCount = 0;
    Point3D coefficients[4];

    Point points[Matrix4x4::kTransformAndClipRectMaxVerts];
    size_t pointCount =
        flatTransform.TransformAndClipRect(aVisibleRect, viewportClip, points);
    for (size_t i = 0; i < pointCount; i++) {
      points[i] = Point((points[i].x * 0.5f + 0.5f) * mViewportSize.width,
                        (points[i].y * 0.5f + 0.5f) * mViewportSize.height);
    }
    if (pointCount > 2) {
      // Use shoelace formula on a triangle in the clipped quad to determine if
      // winding order is reversed.  Iterate through the triangles until one is
      // found with a non-zero area.
      float winding = 0.0f;
      size_t wp = 0;
      while (winding == 0.0f && wp < pointCount) {
        int wp1 = (wp + 1) % pointCount;
        int wp2 = (wp + 2) % pointCount;
        winding = (points[wp1].x - points[wp].x).value *
                      (points[wp1].y + points[wp].y).value +
                  (points[wp2].x - points[wp1].x).value *
                      (points[wp2].y + points[wp1].y).value +
                  (points[wp].x - points[wp2].x).value *
                      (points[wp].y + points[wp2].y).value;
        wp++;
      }
      bool frontFacing = winding >= 0.0f;

      // Calculate the line coefficients used by the DEAA shader to determine
      // the sub-pixel coverage of the edge pixels
      for (size_t i = 0; i < pointCount; i++) {
        const Point& p1 = points[i];
        const Point& p2 = points[(i + 1) % pointCount];
        // Create a DEAA edge for any non-straight lines, to a maximum of 4
        if (p1.x != p2.x && p1.y != p2.y && edgeCount < 4) {
          if (frontFacing) {
            coefficients[edgeCount++] = GetLineCoefficients(p2, p1);
          } else {
            coefficients[edgeCount++] = GetLineCoefficients(p1, p2);
          }
        }
      }
    }

    // The coefficients that are not needed must not cull any fragments.
    // We fill these unused coefficients with a clipping plane that has no
    // effect.
    for (size_t i = edgeCount; i < 4; i++) {
      coefficients[i] = Point3D(0.0f, 1.0f, mViewportSize.height);
    }

    // Set uniforms required by DEAA shader
    Matrix4x4 transformInverted = aTransform;
    transformInverted.Invert();
    program->SetLayerTransformInverse(transformInverted);
    program->SetDEAAEdges(coefficients);
    program->SetVisibleCenter(aVisibleRect.Center());
    program->SetViewportSize(mViewportSize);
  }

  bool didSetBlendMode = false;

  switch (aEffectChain.mPrimaryEffect->mType) {
    case EffectTypes::RGB: {
      TexturedEffect* texturedEffect =
          static_cast<TexturedEffect*>(aEffectChain.mPrimaryEffect.get());
      TextureSource* source = texturedEffect->mTexture;

      didSetBlendMode = SetBlendMode(gl(), gfx::CompositionOp::OP_OVER,
                                     texturedEffect->mPremultiplied);

      gfx::SamplingFilter samplingFilter = texturedEffect->mSamplingFilter;

      source->AsSourceOGL()->BindTexture(LOCAL_GL_TEXTURE0, samplingFilter);

      program->SetTextureUnit(0);

      Matrix4x4 textureTransform = source->AsSourceOGL()->GetTextureTransform();
      program->SetTextureTransform(textureTransform);

      BindAndDrawGeometryWithTextureRect(
          program, aGeometry, texturedEffect->mTextureCoords, source);
      source->AsSourceOGL()->MaybeFenceTexture();
    } break;
    case EffectTypes::YCBCR: {
      EffectYCbCr* effectYCbCr =
          static_cast<EffectYCbCr*>(aEffectChain.mPrimaryEffect.get());
      TextureSource* sourceYCbCr = effectYCbCr->mTexture;
      const int Y = 0, Cb = 1, Cr = 2;
      TextureSourceOGL* sourceY = sourceYCbCr->GetSubSource(Y)->AsSourceOGL();
      TextureSourceOGL* sourceCb = sourceYCbCr->GetSubSource(Cb)->AsSourceOGL();
      TextureSourceOGL* sourceCr = sourceYCbCr->GetSubSource(Cr)->AsSourceOGL();

      if (!sourceY || !sourceCb || !sourceCr) {
        NS_WARNING("Invalid layer texture.");
        return;
      }

      sourceY->BindTexture(LOCAL_GL_TEXTURE0, effectYCbCr->mSamplingFilter);
      sourceCb->BindTexture(LOCAL_GL_TEXTURE1, effectYCbCr->mSamplingFilter);
      sourceCr->BindTexture(LOCAL_GL_TEXTURE2, effectYCbCr->mSamplingFilter);

      if (config.mFeatures & ENABLE_TEXTURE_RECT) {
        // This is used by IOSurface that use 0,0...w,h coordinate rather then
        // 0,0..1,1.
        program->SetCbCrTexCoordMultiplier(sourceCb->GetSize().width,
                                           sourceCb->GetSize().height);
      }

      program->SetYCbCrTextureUnits(Y, Cb, Cr);
      program->SetTextureTransform(Matrix4x4());
      program->SetYUVColorSpace(effectYCbCr->mYUVColorSpace);

      BindAndDrawGeometryWithTextureRect(program, aGeometry,
                                         effectYCbCr->mTextureCoords,
                                         sourceYCbCr->GetSubSource(Y));
      sourceY->MaybeFenceTexture();
      sourceCb->MaybeFenceTexture();
      sourceCr->MaybeFenceTexture();
    } break;
    case EffectTypes::NV12: {
      EffectNV12* effectNV12 =
          static_cast<EffectNV12*>(aEffectChain.mPrimaryEffect.get());
      TextureSource* sourceNV12 = effectNV12->mTexture;
      const int Y = 0, CbCr = 1;
      TextureSourceOGL* sourceY = sourceNV12->GetSubSource(Y)->AsSourceOGL();
      TextureSourceOGL* sourceCbCr =
          sourceNV12->GetSubSource(CbCr)->AsSourceOGL();

      if (!sourceY || !sourceCbCr) {
        NS_WARNING("Invalid layer texture.");
        return;
      }

      sourceY->BindTexture(LOCAL_GL_TEXTURE0, effectNV12->mSamplingFilter);
      sourceCbCr->BindTexture(LOCAL_GL_TEXTURE1, effectNV12->mSamplingFilter);

      if (config.mFeatures & ENABLE_TEXTURE_RECT) {
        // This is used by IOSurface that use 0,0...w,h coordinate rather then
        // 0,0..1,1.
        program->SetCbCrTexCoordMultiplier(sourceCbCr->GetSize().width,
                                           sourceCbCr->GetSize().height);
      }

      program->SetNV12TextureUnits(Y, CbCr);
      program->SetTextureTransform(Matrix4x4());
      program->SetYUVColorSpace(effectNV12->mYUVColorSpace);

      BindAndDrawGeometryWithTextureRect(program, aGeometry,
                                         effectNV12->mTextureCoords,
                                         sourceNV12->GetSubSource(Y));
      sourceY->MaybeFenceTexture();
      sourceCbCr->MaybeFenceTexture();
    } break;
    default:
      MOZ_ASSERT(false, "Unhandled effect type");
      break;
  }

  if (didSetBlendMode) {
    gl()->fBlendFuncSeparate(LOCAL_GL_ONE, LOCAL_GL_ONE_MINUS_SRC_ALPHA,
                             LOCAL_GL_ONE, LOCAL_GL_ONE_MINUS_SRC_ALPHA);
  }

  // in case rendering has used some other GL context
  MakeCurrent();
}

void CompositorOGL::BindAndDrawGeometry(ShaderProgramOGL* aProgram,
                                        const gfx::Rect& aRect) {
  BindAndDrawQuad(aProgram, aRect);
}

void CompositorOGL::BindAndDrawGeometry(
    ShaderProgramOGL* aProgram,
    const nsTArray<gfx::TexturedTriangle>& aTriangles) {
  NS_ASSERTION(aProgram->HasInitialized(),
               "Shader program not correctly initialized");

  const nsTArray<TexturedVertex> vertices =
      TexturedTrianglesToVertexArray(aTriangles);

  mGLContext->fBindBuffer(LOCAL_GL_ARRAY_BUFFER, mTriangleVBO);
  mGLContext->fBufferData(LOCAL_GL_ARRAY_BUFFER,
                          vertices.Length() * sizeof(TexturedVertex),
                          vertices.Elements(), LOCAL_GL_STREAM_DRAW);

  const GLsizei stride = 4 * sizeof(GLfloat);
  InitializeVAO(kCoordinateAttributeIndex, 2, stride, 0);
  InitializeVAO(kTexCoordinateAttributeIndex, 2, stride, 2 * sizeof(GLfloat));

  mGLContext->fDrawArrays(LOCAL_GL_TRIANGLES, 0, vertices.Length());

  mGLContext->fDisableVertexAttribArray(kCoordinateAttributeIndex);
  mGLContext->fDisableVertexAttribArray(kTexCoordinateAttributeIndex);
  mGLContext->fBindBuffer(LOCAL_GL_ARRAY_BUFFER, 0);
}

// |aRect| is the rectangle we want to draw to. We will draw it with
// up to 4 draw commands if necessary to avoid wrapping.
// |aTexCoordRect| is the rectangle from the texture that we want to
// draw using the given program.
// |aTexture| is the texture we are drawing. Its actual size can be
// larger than the rectangle given by |texCoordRect|.
void CompositorOGL::BindAndDrawGeometryWithTextureRect(
    ShaderProgramOGL* aProg, const Rect& aRect, const Rect& aTexCoordRect,
    TextureSource* aTexture) {
  Rect scaledTexCoordRect = GetTextureCoordinates(aTexCoordRect, aTexture);
  Rect layerRects[4];
  Rect textureRects[4];
  size_t rects = DecomposeIntoNoRepeatRects(aRect, scaledTexCoordRect,
                                            &layerRects, &textureRects);

  BindAndDrawQuads(aProg, rects, layerRects, textureRects);
}

void CompositorOGL::BindAndDrawGeometryWithTextureRect(
    ShaderProgramOGL* aProg, const nsTArray<gfx::TexturedTriangle>& aTriangles,
    const gfx::Rect& aTexCoordRect, TextureSource* aTexture) {
  BindAndDrawGeometry(aProg, aTriangles);
}

void CompositorOGL::BindAndDrawQuads(ShaderProgramOGL* aProg, int aQuads,
                                     const Rect* aLayerRects,
                                     const Rect* aTextureRects) {
  NS_ASSERTION(aProg->HasInitialized(),
               "Shader program not correctly initialized");

  mGLContext->fBindBuffer(LOCAL_GL_ARRAY_BUFFER, mQuadVBO);
  InitializeVAO(kCoordinateAttributeIndex, 4, 0, 0);

  aProg->SetLayerRects(aLayerRects);
  if (aProg->GetTextureCount() > 0) {
    aProg->SetTextureRects(aTextureRects);
  }

  // We are using GL_TRIANGLES here because the Mac Intel drivers fail to
  // properly process uniform arrays with GL_TRIANGLE_STRIP. Go figure.
  mGLContext->fDrawArrays(LOCAL_GL_TRIANGLES, 0, 6 * aQuads);
  mGLContext->fDisableVertexAttribArray(kCoordinateAttributeIndex);
  mGLContext->fBindBuffer(LOCAL_GL_ARRAY_BUFFER, 0);
}

void CompositorOGL::InitializeVAO(const GLuint aAttrib, const GLint aComponents,
                                  const GLsizei aStride, const size_t aOffset) {
  mGLContext->fVertexAttribPointer(aAttrib, aComponents, LOCAL_GL_FLOAT,
                                   LOCAL_GL_FALSE, aStride,
                                   reinterpret_cast<GLvoid*>(aOffset));
  mGLContext->fEnableVertexAttribArray(aAttrib);
}

#ifdef MOZ_DUMP_PAINTING
template <typename T>
void WriteSnapshotToDumpFile_internal(T* aObj, DataSourceSurface* aSurf) {
  nsCString string(aObj->Name());
  string.Append('-');
  string.AppendInt((uint64_t)aObj);
  if (gfxUtils::sDumpPaintFile != stderr) {
    fprintf_stderr(gfxUtils::sDumpPaintFile, R"(array["%s"]=")",
                   string.BeginReading());
  }
  gfxUtils::DumpAsDataURI(aSurf, gfxUtils::sDumpPaintFile);
  if (gfxUtils::sDumpPaintFile != stderr) {
    fprintf_stderr(gfxUtils::sDumpPaintFile, R"(";)");
  }
}

void WriteSnapshotToDumpFile(Compositor* aCompositor, DrawTarget* aTarget) {
  RefPtr<SourceSurface> surf = aTarget->Snapshot();
  RefPtr<DataSourceSurface> dSurf = surf->GetDataSurface();
  WriteSnapshotToDumpFile_internal(aCompositor, dSurf);
}
#endif

void CompositorOGL::EndFrame() {
  AUTO_PROFILER_LABEL("CompositorOGL::EndFrame", GRAPHICS);

#ifdef MOZ_DUMP_PAINTING
  if (gfxEnv::MOZ_DISABLE_FORCE_PRESENT()) {
    LayoutDeviceIntSize size;
    if (mUseExternalSurfaceSize) {
      size = LayoutDeviceIntSize(mSurfaceSize.width, mSurfaceSize.height);
    } else {
      size = mWidget->GetClientSize();
    }
    RefPtr<DrawTarget> target =
        gfxPlatform::GetPlatform()->CreateOffscreenContentDrawTarget(
            IntSize(size.width, size.height), SurfaceFormat::B8G8R8A8);
    if (target) {
      CopyToTarget(target, nsIntPoint(), Matrix());
      WriteSnapshotToDumpFile(this, target);
    }
  }
#endif

  mFrameInProgress = false;
  mShouldInvalidateWindow = false;

  if (mTarget) {
    CopyToTarget(mTarget, mTargetBounds.TopLeft(), Matrix());
    mGLContext->fBindBuffer(LOCAL_GL_ARRAY_BUFFER, 0);
    mTarget = nullptr;
    mWindowRenderTarget = nullptr;
    mCurrentRenderTarget = nullptr;
    Compositor::EndFrame();
    return;
  }

  mWindowRenderTarget = nullptr;
  mCurrentRenderTarget = nullptr;

  if (mTexturePool) {
    mTexturePool->EndFrame();
  }

  InsertFrameDoneSync();

  mGLContext->SetDamage(mCurrentFrameInvalidRegion);
  mGLContext->SwapBuffers();
  mGLContext->fBindBuffer(LOCAL_GL_ARRAY_BUFFER, 0);

  // Unbind all textures
  for (GLuint i = 0; i <= 4; i++) {
    mGLContext->fActiveTexture(LOCAL_GL_TEXTURE0 + i);
    mGLContext->fBindTexture(LOCAL_GL_TEXTURE_2D, 0);
    if (!mGLContext->IsGLES()) {
      mGLContext->fBindTexture(LOCAL_GL_TEXTURE_RECTANGLE_ARB, 0);
    }
  }

  mCurrentFrameInvalidRegion.SetEmpty();

  Compositor::EndFrame();
}

void CompositorOGL::InsertFrameDoneSync() {
#ifdef XP_MACOSX
  // Only do this on macOS.
  // On other platforms, SwapBuffers automatically applies back-pressure.
  if (mThisFrameDoneSync) {
    mGLContext->fDeleteSync(mThisFrameDoneSync);
  }
  mThisFrameDoneSync =
      mGLContext->fFenceSync(LOCAL_GL_SYNC_GPU_COMMANDS_COMPLETE, 0);
#elif defined(MOZ_WIDGET_ANDROID)
  const auto& gle = gl::GLContextEGL::Cast(mGLContext);
  const auto& egl = gle->mEgl;

  EGLSync sync = nullptr;
  if (AndroidHardwareBufferApi::Get()) {
    sync = egl->fCreateSync(LOCAL_EGL_SYNC_NATIVE_FENCE_ANDROID, nullptr);
  }
  if (sync) {
    int fenceFd = egl->fDupNativeFenceFDANDROID(sync);
    if (fenceFd >= 0) {
      mReleaseFenceFd = ipc::FileDescriptor(UniqueFileHandle(fenceFd));
    }
    egl->fDestroySync(sync);
    sync = nullptr;
  }
#endif
}

ipc::FileDescriptor CompositorOGL::GetReleaseFence() { return mReleaseFenceFd; }

bool CompositorOGL::NeedToRecreateFullWindowRenderTarget() const {
  if (!ShouldRecordFrames()) {
    return false;
  }
  if (!mFullWindowRenderTarget) {
    return true;
  }
  IntSize windowSize = mWidget->GetClientSize().ToUnknownSize();
  return mFullWindowRenderTarget->GetSize() != windowSize;
}

void CompositorOGL::SetDestinationSurfaceSize(const IntSize& aSize) {
  mSurfaceSize.width = aSize.width;
  mSurfaceSize.height = aSize.height;
}

void CompositorOGL::CopyToTarget(DrawTarget* aTarget,
                                 const nsIntPoint& aTopLeft,
                                 const gfx::Matrix& aTransform) {
  MOZ_ASSERT(aTarget);
  IntRect rect;
  if (mUseExternalSurfaceSize) {
    rect = IntRect(0, 0, mSurfaceSize.width, mSurfaceSize.height);
  } else {
    rect = IntRect(0, 0, mWidgetSize.width, mWidgetSize.height);
  }
  GLint width = rect.Width();
  GLint height = rect.Height();

  if ((int64_t(width) * int64_t(height) * int64_t(4)) > INT32_MAX) {
    NS_ERROR("Widget size too big - integer overflow!");
    return;
  }

  RefPtr<DataSourceSurface> source = Factory::CreateDataSourceSurface(
      rect.Size(), gfx::SurfaceFormat::B8G8R8A8);
  if (NS_WARN_IF(!source)) {
    return;
  }

  ReadPixelsIntoDataSurface(mGLContext, source);

  // Map from GL space to Cairo space and reverse the world transform.
  Matrix glToCairoTransform = aTransform;
  glToCairoTransform.Invert();
  glToCairoTransform.PreScale(1.0, -1.0);
  glToCairoTransform.PreTranslate(0.0, -height);

  glToCairoTransform.PostTranslate(-aTopLeft.x, -aTopLeft.y);

  Matrix oldMatrix = aTarget->GetTransform();
  aTarget->SetTransform(glToCairoTransform);
  Rect floatRect = Rect(rect.X(), rect.Y(), width, height);
  aTarget->DrawSurface(source, floatRect, floatRect, DrawSurfaceOptions(),
                       DrawOptions(1.0f, CompositionOp::OP_SOURCE));
  aTarget->SetTransform(oldMatrix);
  aTarget->Flush();
}

void CompositorOGL::Pause() {
#ifdef MOZ_WIDGET_ANDROID
  if (!gl() || gl()->IsDestroyed()) return;
  // ReleaseSurface internally calls MakeCurrent
  gl()->ReleaseSurface();
#elif defined(MOZ_WAYLAND)
  // ReleaseSurface internally calls MakeCurrent
  gl()->ReleaseSurface();
#endif
}

bool CompositorOGL::Resume() {
#if defined(MOZ_WIDGET_ANDROID) || defined(MOZ_WIDGET_UIKIT) || \
    defined(MOZ_WAYLAND)
  if (!gl() || gl()->IsDestroyed()) return false;

  // RenewSurface internally calls MakeCurrent.
  return gl()->RenewSurface(GetWidget());
#else
  return true;
#endif
}

already_AddRefed<DataTextureSource> CompositorOGL::CreateDataTextureSource(
    TextureFlags aFlags) {
  if (!gl()) {
    return nullptr;
  }

  return MakeAndAddRef<TextureImageTextureSourceOGL>(this, aFlags);
}

int32_t CompositorOGL::GetMaxTextureSize() const {
  MOZ_ASSERT(mGLContext);
  GLint texSize = 0;
  mGLContext->fGetIntegerv(LOCAL_GL_MAX_TEXTURE_SIZE, &texSize);
  MOZ_ASSERT(texSize != 0);
  return texSize;
}

void CompositorOGL::MakeCurrent(MakeCurrentFlags aFlags) {
  if (mDestroyed) {
    NS_WARNING("Call on destroyed layer manager");
    return;
  }
  mGLContext->MakeCurrent(aFlags & ForceMakeCurrent);
}

GLuint CompositorOGL::GetTemporaryTexture(GLenum aTarget, GLenum aUnit) {
  if (!mTexturePool) {
    mTexturePool = new PerUnitTexturePoolOGL(gl());
  }
  return mTexturePool->GetTexture(aTarget, aUnit);
}

GLuint PerUnitTexturePoolOGL::GetTexture(GLenum aTarget, GLenum aTextureUnit) {
  if (mTextureTarget == 0) {
    mTextureTarget = aTarget;
  }
  MOZ_ASSERT(mTextureTarget == aTarget);

  size_t index = aTextureUnit - LOCAL_GL_TEXTURE0;
  // lazily grow the array of temporary textures
  if (mTextures.Length() <= index) {
    size_t prevLength = mTextures.Length();
    mTextures.SetLength(index + 1);
    for (unsigned int i = prevLength; i <= index; ++i) {
      mTextures[i] = 0;
    }
  }
  // lazily initialize the temporary textures
  if (!mTextures[index]) {
    if (!mGL->MakeCurrent()) {
      return 0;
    }
    mGL->fGenTextures(1, &mTextures[index]);
    mGL->fBindTexture(aTarget, mTextures[index]);
    mGL->fTexParameteri(aTarget, LOCAL_GL_TEXTURE_WRAP_S,
                        LOCAL_GL_CLAMP_TO_EDGE);
    mGL->fTexParameteri(aTarget, LOCAL_GL_TEXTURE_WRAP_T,
                        LOCAL_GL_CLAMP_TO_EDGE);
  }
  return mTextures[index];
}

void PerUnitTexturePoolOGL::DestroyTextures() {
  if (mGL && mGL->MakeCurrent()) {
    if (mTextures.Length() > 0) {
      mGL->fDeleteTextures(mTextures.Length(), &mTextures[0]);
    }
  }
  mTextures.SetLength(0);
}

void CompositorOGL::RegisterTextureSource(TextureSource* aTextureSource) {
#ifdef MOZ_WIDGET_GTK
  if (mDestroyed) {
    return;
  }
  mRegisteredTextureSources.insert(aTextureSource);
#endif
}

void CompositorOGL::UnregisterTextureSource(TextureSource* aTextureSource) {
#ifdef MOZ_WIDGET_GTK
  if (mDestroyed) {
    return;
  }
  mRegisteredTextureSources.erase(aTextureSource);
#endif
}

}  // namespace layers
}  // namespace mozilla