summaryrefslogtreecommitdiffstats
path: root/src/mesa/main/formats.c
blob: d0c9c0028b2cea90d3bc0bedbe2410523f092c1d (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
/*
 * Mesa 3-D graphics library
 * Version:  7.7
 *
 * Copyright (C) 1999-2008  Brian Paul   All Rights Reserved.
 * Copyright (c) 2008-2009  VMware, Inc.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included
 * in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
 * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */


#include "imports.h"
#include "formats.h"
#include "config.h"


/**
 * Information about texture formats.
 */
struct gl_format_info
{
   gl_format Name;

   /** text name for debugging */
   const char *StrName;

   /**
    * Base format is one of GL_RGB, GL_RGBA, GL_ALPHA, GL_LUMINANCE,
    * GL_LUMINANCE_ALPHA, GL_INTENSITY, GL_YCBCR_MESA, GL_COLOR_INDEX,
    * GL_DEPTH_COMPONENT, GL_STENCIL_INDEX, GL_DEPTH_STENCIL.
    */
   GLenum BaseFormat;

   /**
    * Logical data type: one of  GL_UNSIGNED_NORMALIZED, GL_SIGNED_NORMALED,
    * GL_UNSIGNED_INT, GL_SIGNED_INT, GL_FLOAT.
    */
   GLenum DataType;

   GLubyte RedBits;
   GLubyte GreenBits;
   GLubyte BlueBits;
   GLubyte AlphaBits;
   GLubyte LuminanceBits;
   GLubyte IntensityBits;
   GLubyte IndexBits;
   GLubyte DepthBits;
   GLubyte StencilBits;

   /**
    * To describe compressed formats.  If not compressed, Width=Height=1.
    */
   GLubyte BlockWidth, BlockHeight;
   GLubyte BytesPerBlock;
};


/**
 * Info about each format.
 * These must be in the same order as the MESA_FORMAT_* enums so that
 * we can do lookups without searching.
 */
static struct gl_format_info format_info[MESA_FORMAT_COUNT] =
{
   {
      MESA_FORMAT_NONE,            /* Name */
      "MESA_FORMAT_NONE",          /* StrName */
      GL_NONE,                     /* BaseFormat */
      GL_NONE,                     /* DataType */
      0, 0, 0, 0,                  /* Red/Green/Blue/AlphaBits */
      0, 0, 0, 0, 0,               /* Lum/Int/Index/Depth/StencilBits */
      0, 0, 0                      /* BlockWidth/Height,Bytes */
   },
   {
      MESA_FORMAT_RGBA8888,        /* Name */
      "MESA_FORMAT_RGBA8888",      /* StrName */
      GL_RGBA,                     /* BaseFormat */
      GL_UNSIGNED_NORMALIZED,      /* DataType */
      8, 8, 8, 8,                  /* Red/Green/Blue/AlphaBits */
      0, 0, 0, 0, 0,               /* Lum/Int/Index/Depth/StencilBits */
      1, 1, 4                      /* BlockWidth/Height,Bytes */
   },
   {
      MESA_FORMAT_RGBA8888_REV,    /* Name */
      "MESA_FORMAT_RGBA8888_REV",  /* StrName */
      GL_RGBA,                     /* BaseFormat */
      GL_UNSIGNED_NORMALIZED,      /* DataType */
      8, 8, 8, 8,                  /* Red/Green/Blue/AlphaBits */
      0, 0, 0, 0, 0,               /* Lum/Int/Index/Depth/StencilBits */
      1, 1, 4                      /* BlockWidth/Height,Bytes */
   },
   {
      MESA_FORMAT_ARGB8888,        /* Name */
      "MESA_FORMAT_ARGB8888",      /* StrName */
      GL_RGBA,                     /* BaseFormat */
      GL_UNSIGNED_NORMALIZED,      /* DataType */
      8, 8, 8, 8,                  /* Red/Green/Blue/AlphaBits */
      0, 0, 0, 0, 0,               /* Lum/Int/Index/Depth/StencilBits */
      1, 1, 4                      /* BlockWidth/Height,Bytes */
   },
   {
      MESA_FORMAT_ARGB8888_REV,    /* Name */
      "MESA_FORMAT_ARGB8888_REV",  /* StrName */
      GL_RGBA,                     /* BaseFormat */
      GL_UNSIGNED_NORMALIZED,      /* DataType */
      8, 8, 8, 8,                  /* Red/Green/Blue/AlphaBits */
      0, 0, 0, 0, 0,               /* Lum/Int/Index/Depth/StencilBits */
      1, 1, 4                      /* BlockWidth/Height,Bytes */
   },
   {
      MESA_FORMAT_XRGB8888,        /* Name */
      "MESA_FORMAT_XRGB8888",      /* StrName */
      GL_RGB,                      /* BaseFormat */
      GL_UNSIGNED_NORMALIZED,      /* DataType */
      8, 8, 8, 0,                  /* Red/Green/Blue/AlphaBits */
      0, 0, 0, 0, 0,               /* Lum/Int/Index/Depth/StencilBits */
      1, 1, 4                      /* BlockWidth/Height,Bytes */
   },
   {
      MESA_FORMAT_XRGB8888_REV,    /* Name */
      "MESA_FORMAT_XRGB8888_REV",  /* StrName */
      GL_RGB,                      /* BaseFormat */
      GL_UNSIGNED_NORMALIZED,      /* DataType */
      8, 8, 8, 0,                  /* Red/Green/Blue/AlphaBits */
      0, 0, 0, 0, 0,               /* Lum/Int/Index/Depth/StencilBits */
      1, 1, 4                      /* BlockWidth/Height,Bytes */
   },
   {
      MESA_FORMAT_RGB888,          /* Name */
      "MESA_FORMAT_RGB888",        /* StrName */
      GL_RGB,                      /* BaseFormat */
      GL_UNSIGNED_NORMALIZED,      /* DataType */
      8, 8, 8, 0,                  /* Red/Green/Blue/AlphaBits */
      0, 0, 0, 0, 0,               /* Lum/Int/Index/Depth/StencilBits */
      1, 1, 3                      /* BlockWidth/Height,Bytes */
   },
   {
      MESA_FORMAT_BGR888,          /* Name */
      "MESA_FORMAT_BGR888",        /* StrName */
      GL_RGB,                      /* BaseFormat */
      GL_UNSIGNED_NORMALIZED,      /* DataType */
      8, 8, 8, 0,                  /* Red/Green/Blue/AlphaBits */
      0, 0, 0, 0, 0,               /* Lum/Int/Index/Depth/StencilBits */
      1, 1, 3                      /* BlockWidth/Height,Bytes */
   },
   {
      MESA_FORMAT_RGB565,          /* Name */
      "MESA_FORMAT_RGB565",        /* StrName */
      GL_RGB,                      /* BaseFormat */
      GL_UNSIGNED_NORMALIZED,      /* DataType */
      5, 6, 5, 0,                  /* Red/Green/Blue/AlphaBits */
      0, 0, 0, 0, 0,               /* Lum/Int/Index/Depth/StencilBits */
      1, 1, 2                      /* BlockWidth/Height,Bytes */
   },
   {
      MESA_FORMAT_RGB565_REV,      /* Name */
      "MESA_FORMAT_RGB565_REV",    /* StrName */
      GL_RGB,                      /* BaseFormat */
      GL_UNSIGNED_NORMALIZED,      /* DataType */
      5, 6, 5, 0,                  /* Red/Green/Blue/AlphaBits */
      0, 0, 0, 0, 0,               /* Lum/Int/Index/Depth/StencilBits */
      1, 1, 2                      /* BlockWidth/Height,Bytes */
   },
   {
      MESA_FORMAT_ARGB4444,        /* Name */
      "MESA_FORMAT_ARGB4444",      /* StrName */
      GL_RGBA,                     /* BaseFormat */
      GL_UNSIGNED_NORMALIZED,      /* DataType */
      4, 4, 4, 4,                  /* Red/Green/Blue/AlphaBits */
      0, 0, 0, 0, 0,               /* Lum/Int/Index/Depth/StencilBits */
      1, 1, 2                      /* BlockWidth/Height,Bytes */
   },
   {
      MESA_FORMAT_ARGB4444_REV,    /* Name */
      "MESA_FORMAT_ARGB4444_REV",  /* StrName */
      GL_RGBA,                     /* BaseFormat */
      GL_UNSIGNED_NORMALIZED,      /* DataType */
      4, 4, 4, 4,                  /* Red/Green/Blue/AlphaBits */
      0, 0, 0, 0, 0,               /* Lum/Int/Index/Depth/StencilBits */
      1, 1, 2                      /* BlockWidth/Height,Bytes */
   },
   {
      MESA_FORMAT_RGBA5551,        /* Name */
      "MESA_FORMAT_RGBA5551",      /* StrName */
      GL_RGBA,                     /* BaseFormat */
      GL_UNSIGNED_NORMALIZED,      /* DataType */
      5, 5, 5, 1,                  /* Red/Green/Blue/AlphaBits */
      0, 0, 0, 0, 0,               /* Lum/Int/Index/Depth/StencilBits */
      1, 1, 2                      /* BlockWidth/Height,Bytes */
   },
   {
      MESA_FORMAT_ARGB1555,        /* Name */
      "MESA_FORMAT_ARGB1555",      /* StrName */
      GL_RGBA,                     /* BaseFormat */
      GL_UNSIGNED_NORMALIZED,      /* DataType */
      5, 5, 5, 1,                  /* Red/Green/Blue/AlphaBits */
      0, 0, 0, 0, 0,               /* Lum/Int/Index/Depth/StencilBits */
      1, 1, 2                      /* BlockWidth/Height,Bytes */
   },
   {
      MESA_FORMAT_ARGB1555_REV,    /* Name */
      "MESA_FORMAT_ARGB1555_REV",  /* StrName */
      GL_RGBA,                     /* BaseFormat */
      GL_UNSIGNED_NORMALIZED,      /* DataType */
      5, 5, 5, 1,                  /* Red/Green/Blue/AlphaBits */
      0, 0, 0, 0, 0,               /* Lum/Int/Index/Depth/StencilBits */
      1, 1, 2                      /* BlockWidth/Height,Bytes */
   },
   {
      MESA_FORMAT_AL88,            /* Name */
      "MESA_FORMAT_AL88",          /* StrName */
      GL_LUMINANCE_ALPHA,          /* BaseFormat */
      GL_UNSIGNED_NORMALIZED,      /* DataType */
      0, 0, 0, 8,                  /* Red/Green/Blue/AlphaBits */
      8, 0, 0, 0, 0,               /* Lum/Int/Index/Depth/StencilBits */
      1, 1, 2                      /* BlockWidth/Height,Bytes */
   },
   {
      MESA_FORMAT_AL88_REV,        /* Name */
      "MESA_FORMAT_AL88_REV",      /* StrName */
      GL_LUMINANCE_ALPHA,          /* BaseFormat */
      GL_UNSIGNED_NORMALIZED,      /* DataType */
      0, 0, 0, 8,                  /* Red/Green/Blue/AlphaBits */
      8, 0, 0, 0, 0,               /* Lum/Int/Index/Depth/StencilBits */
      1, 1, 2                      /* BlockWidth/Height,Bytes */
   },
   {
      MESA_FORMAT_AL1616,          /* Name */
      "MESA_FORMAT_AL1616",        /* StrName */
      GL_LUMINANCE_ALPHA,          /* BaseFormat */
      GL_UNSIGNED_NORMALIZED,      /* DataType */
      0, 0, 0, 16,                 /* Red/Green/Blue/AlphaBits */
      16, 0, 0, 0, 0,              /* Lum/Int/Index/Depth/StencilBits */
      1, 1, 4                      /* BlockWidth/Height,Bytes */
   },
   {
      MESA_FORMAT_AL1616_REV,      /* Name */
      "MESA_FORMAT_AL1616_REV",    /* StrName */
      GL_LUMINANCE_ALPHA,          /* BaseFormat */
      GL_UNSIGNED_NORMALIZED,      /* DataType */
      0, 0, 0, 16,                 /* Red/Green/Blue/AlphaBits */
      16, 0, 0, 0, 0,              /* Lum/Int/Index/Depth/StencilBits */
      1, 1, 4                      /* BlockWidth/Height,Bytes */
   },
   {
      MESA_FORMAT_RGB332,          /* Name */
      "MESA_FORMAT_RGB332",        /* StrName */
      GL_RGB,                      /* BaseFormat */
      GL_UNSIGNED_NORMALIZED,      /* DataType */
      3, 3, 2, 0,                  /* Red/Green/Blue/AlphaBits */
      0, 0, 0, 0, 0,               /* Lum/Int/Index/Depth/StencilBits */
      1, 1, 1                      /* BlockWidth/Height,Bytes */
   },
   {
      MESA_FORMAT_A8,              /* Name */
      "MESA_FORMAT_A8",            /* StrName */
      GL_ALPHA,                    /* BaseFormat */
      GL_UNSIGNED_NORMALIZED,      /* DataType */
      0, 0, 0, 8,                  /* Red/Green/Blue/AlphaBits */
      0, 0, 0, 0, 0,               /* Lum/Int/Index/Depth/StencilBits */
      1, 1, 1                      /* BlockWidth/Height,Bytes */
   },
   {
      MESA_FORMAT_L8,              /* Name */
      "MESA_FORMAT_L8",            /* StrName */
      GL_LUMINANCE,                /* BaseFormat */
      GL_UNSIGNED_NORMALIZED,      /* DataType */
      0, 0, 0, 0,                  /* Red/Green/Blue/AlphaBits */
      8, 0, 0, 0, 0,               /* Lum/Int/Index/Depth/StencilBits */
      1, 1, 1                      /* BlockWidth/Height,Bytes */
   },
   {
      MESA_FORMAT_I8,              /* Name */
      "MESA_FORMAT_I8",            /* StrName */
      GL_INTENSITY,                /* BaseFormat */
      GL_UNSIGNED_NORMALIZED,      /* DataType */
      0, 0, 0, 0,                  /* Red/Green/Blue/AlphaBits */
      0, 8, 0, 0, 0,               /* Lum/Int/Index/Depth/StencilBits */
      1, 1, 1                      /* BlockWidth/Height,Bytes */
   },
   {
      MESA_FORMAT_CI8,             /* Name */
      "MESA_FORMAT_CI8",           /* StrName */
      GL_COLOR_INDEX,              /* BaseFormat */
      GL_UNSIGNED_INT,             /* DataType */
      0, 0, 0, 0,                  /* Red/Green/Blue/AlphaBits */
      0, 0, 8, 0, 0,               /* Lum/Int/Index/Depth/StencilBits */
      1, 1, 1                      /* BlockWidth/Height,Bytes */
   },
   {
      MESA_FORMAT_YCBCR,           /* Name */
      "MESA_FORMAT_YCBCR",         /* StrName */
      GL_YCBCR_MESA,               /* BaseFormat */
      GL_UNSIGNED_NORMALIZED,      /* DataType */
      0, 0, 0, 0,                  /* Red/Green/Blue/AlphaBits */
      0, 0, 0, 0, 0,               /* Lum/Int/Index/Depth/StencilBits */
      1, 1, 2                      /* BlockWidth/Height,Bytes */
   },
   {
      MESA_FORMAT_YCBCR_REV,       /* Name */
      "MESA_FORMAT_YCBCR_REV",     /* StrName */
      GL_YCBCR_MESA,               /* BaseFormat */
      GL_UNSIGNED_NORMALIZED,      /* DataType */
      0, 0, 0, 0,                  /* Red/Green/Blue/AlphaBits */
      0, 0, 0, 0, 0,               /* Lum/Int/Index/Depth/StencilBits */
      1, 1, 2                      /* BlockWidth/Height,Bytes */
   },
   {
      MESA_FORMAT_Z24_S8,          /* Name */
      "MESA_FORMAT_Z24_S8",        /* StrName */
      GL_DEPTH_STENCIL,            /* BaseFormat */
      GL_UNSIGNED_INT,             /* DataType */
      0, 0, 0, 0,                  /* Red/Green/Blue/AlphaBits */
      0, 0, 0, 24, 8,              /* Lum/Int/Index/Depth/StencilBits */
      1, 1, 4                      /* BlockWidth/Height,Bytes */
   },
   {
      MESA_FORMAT_S8_Z24,          /* Name */
      "MESA_FORMAT_S8_Z24",        /* StrName */
      GL_DEPTH_STENCIL,            /* BaseFormat */
      GL_UNSIGNED_INT,             /* DataType */
      0, 0, 0, 0,                  /* Red/Green/Blue/AlphaBits */
      0, 0, 0, 24, 8,              /* Lum/Int/Index/Depth/StencilBits */
      1, 1, 4                      /* BlockWidth/Height,Bytes */
   },
   {
      MESA_FORMAT_Z16,             /* Name */
      "MESA_FORMAT_Z16",           /* StrName */
      GL_DEPTH_COMPONENT,          /* BaseFormat */
      GL_UNSIGNED_INT,             /* DataType */
      0, 0, 0, 0,                  /* Red/Green/Blue/AlphaBits */
      0, 0, 0, 16, 0,              /* Lum/Int/Index/Depth/StencilBits */
      1, 1, 2                      /* BlockWidth/Height,Bytes */
   },
   {
      MESA_FORMAT_X8_Z24,          /* Name */
      "MESA_FORMAT_X8_Z24",        /* StrName */
      GL_DEPTH_COMPONENT,          /* BaseFormat */
      GL_UNSIGNED_INT,             /* DataType */
      0, 0, 0, 0,                  /* Red/Green/Blue/AlphaBits */
      0, 0, 0, 24, 0,              /* Lum/Int/Index/Depth/StencilBits */
      1, 1, 4                      /* BlockWidth/Height,Bytes */
   },
   {
      MESA_FORMAT_Z24_X8,          /* Name */
      "MESA_FORMAT_Z24_X8",        /* StrName */
      GL_DEPTH_COMPONENT,          /* BaseFormat */
      GL_UNSIGNED_INT,             /* DataType */
      0, 0, 0, 0,                  /* Red/Green/Blue/AlphaBits */
      0, 0, 0, 24, 0,              /* Lum/Int/Index/Depth/StencilBits */
      1, 1, 4                      /* BlockWidth/Height,Bytes */
   },
   {
      MESA_FORMAT_Z32,             /* Name */
      "MESA_FORMAT_Z32",           /* StrName */
      GL_DEPTH_COMPONENT,          /* BaseFormat */
      GL_UNSIGNED_INT,             /* DataType */
      0, 0, 0, 0,                  /* Red/Green/Blue/AlphaBits */
      0, 0, 0, 32, 0,              /* Lum/Int/Index/Depth/StencilBits */
      1, 1, 4                      /* BlockWidth/Height,Bytes */
   },
   {
      MESA_FORMAT_S8,              /* Name */
      "MESA_FORMAT_S8",            /* StrName */
      GL_STENCIL_INDEX,            /* BaseFormat */
      GL_UNSIGNED_INT,             /* DataType */
      0, 0, 0, 0,                  /* Red/Green/Blue/AlphaBits */
      0, 0, 0, 0, 8,               /* Lum/Int/Index/Depth/StencilBits */
      1, 1, 1                      /* BlockWidth/Height,Bytes */
   },
   {
      MESA_FORMAT_SRGB8,
      "MESA_FORMAT_SRGB8",
      GL_RGB,
      GL_UNSIGNED_NORMALIZED,
      8, 8, 8, 0,
      0, 0, 0, 0, 0,
      1, 1, 3
   },
   {
      MESA_FORMAT_SRGBA8,
      "MESA_FORMAT_SRGBA8",
      GL_RGBA,
      GL_UNSIGNED_NORMALIZED,    
      8, 8, 8, 8,
      0, 0, 0, 0, 0,
      1, 1, 4
   },
   {
      MESA_FORMAT_SARGB8,
      "MESA_FORMAT_SARGB8",
      GL_RGBA,
      GL_UNSIGNED_NORMALIZED,    
      8, 8, 8, 8,
      0, 0, 0, 0, 0,
      1, 1, 4
   },
   {
      MESA_FORMAT_SL8,
      "MESA_FORMAT_SL8",
      GL_LUMINANCE,
      GL_UNSIGNED_NORMALIZED,    
      0, 0, 0, 0,
      8, 0, 0, 0, 0,
      1, 1, 1
   },
   {
      MESA_FORMAT_SLA8,
      "MESA_FORMAT_SLA8",
      GL_LUMINANCE_ALPHA,
      GL_UNSIGNED_NORMALIZED,    
      0, 0, 0, 8,
      8, 0, 0, 0, 0,
      1, 1, 2
   },
   {
      MESA_FORMAT_SRGB_DXT1,       /* Name */
      "MESA_FORMAT_SRGB_DXT1",     /* StrName */
      GL_RGB,                      /* BaseFormat */
      GL_UNSIGNED_NORMALIZED,      /* DataType */
      4, 4, 4, 0,                  /* approx Red/Green/Blue/AlphaBits */
      0, 0, 0, 0, 0,               /* Lum/Int/Index/Depth/StencilBits */
      4, 4, 8                      /* 8 bytes per 4x4 block */
   },
   {
      MESA_FORMAT_SRGBA_DXT1,
      "MESA_FORMAT_SRGBA_DXT1",
      GL_RGBA,
      GL_UNSIGNED_NORMALIZED,
      4, 4, 4, 4,
      0, 0, 0, 0, 0,
      4, 4, 8                      /* 8 bytes per 4x4 block */
   },
   {
      MESA_FORMAT_SRGBA_DXT3,
      "MESA_FORMAT_SRGBA_DXT3",
      GL_RGBA,
      GL_UNSIGNED_NORMALIZED,
      4, 4, 4, 4,
      0, 0, 0, 0, 0,
      4, 4, 16                     /* 16 bytes per 4x4 block */
   },
   {
      MESA_FORMAT_SRGBA_DXT5,
      "MESA_FORMAT_SRGBA_DXT5",
      GL_RGBA,
      GL_UNSIGNED_NORMALIZED,
      4, 4, 4, 4,
      0, 0, 0, 0, 0,
      4, 4, 16                     /* 16 bytes per 4x4 block */
   },

   {
      MESA_FORMAT_RGB_FXT1,
      "MESA_FORMAT_RGB_FXT1",
      GL_RGB,
      GL_UNSIGNED_NORMALIZED,
      4, 4, 4, 0,                  /* approx Red/Green/BlueBits */
      0, 0, 0, 0, 0,
      8, 4, 16                     /* 16 bytes per 8x4 block */
   },
   {
      MESA_FORMAT_RGBA_FXT1,
      "MESA_FORMAT_RGBA_FXT1",
      GL_RGBA,
      GL_UNSIGNED_NORMALIZED,
      4, 4, 4, 1,                  /* approx Red/Green/Blue/AlphaBits */
      0, 0, 0, 0, 0,
      8, 4, 16                     /* 16 bytes per 8x4 block */
   },

   {
      MESA_FORMAT_RGB_DXT1,        /* Name */
      "MESA_FORMAT_RGB_DXT1",      /* StrName */
      GL_RGB,                      /* BaseFormat */
      GL_UNSIGNED_NORMALIZED,      /* DataType */
      4, 4, 4, 0,                  /* approx Red/Green/Blue/AlphaBits */
      0, 0, 0, 0, 0,               /* Lum/Int/Index/Depth/StencilBits */
      4, 4, 8                      /* 8 bytes per 4x4 block */
   },
   {
      MESA_FORMAT_RGBA_DXT1,
      "MESA_FORMAT_RGBA_DXT1",
      GL_RGBA,
      GL_UNSIGNED_NORMALIZED,    
      4, 4, 4, 4,
      0, 0, 0, 0, 0,
      4, 4, 8                      /* 8 bytes per 4x4 block */
   },
   {
      MESA_FORMAT_RGBA_DXT3,
      "MESA_FORMAT_RGBA_DXT3",
      GL_RGBA,
      GL_UNSIGNED_NORMALIZED,    
      4, 4, 4, 4,
      0, 0, 0, 0, 0,
      4, 4, 16                     /* 16 bytes per 4x4 block */
   },
   {
      MESA_FORMAT_RGBA_DXT5,
      "MESA_FORMAT_RGBA_DXT5",
      GL_RGBA,
      GL_UNSIGNED_NORMALIZED,    
      4, 4, 4, 4,
      0, 0, 0, 0, 0,
      4, 4, 16                     /* 16 bytes per 4x4 block */
   },
   {
      MESA_FORMAT_RGBA_FLOAT32,
      "MESA_FORMAT_RGBA_FLOAT32",
      GL_RGBA,
      GL_FLOAT,
      32, 32, 32, 32,
      0, 0, 0, 0, 0,
      1, 1, 16
   },
   {
      MESA_FORMAT_RGBA_FLOAT16,
      "MESA_FORMAT_RGBA_FLOAT16",
      GL_RGBA,
      GL_FLOAT,
      16, 16, 16, 16,
      0, 0, 0, 0, 0,
      1, 1, 8
   },
   {
      MESA_FORMAT_RGB_FLOAT32,
      "MESA_FORMAT_RGB_FLOAT32",
      GL_RGB,
      GL_FLOAT,
      32, 32, 32, 0,
      0, 0, 0, 0, 0,
      1, 1, 12
   },
   {
      MESA_FORMAT_RGB_FLOAT16,
      "MESA_FORMAT_RGB_FLOAT16",
      GL_RGB,
      GL_FLOAT,
      16, 16, 16, 0,
      0, 0, 0, 0, 0,
      1, 1, 6
   },
   {
      MESA_FORMAT_ALPHA_FLOAT32,
      "MESA_FORMAT_ALPHA_FLOAT32",
      GL_ALPHA,
      GL_FLOAT,
      0, 0, 0, 32,
      0, 0, 0, 0, 0,
      1, 1, 4
   },
   {
      MESA_FORMAT_ALPHA_FLOAT16,
      "MESA_FORMAT_ALPHA_FLOAT16",
      GL_ALPHA,
      GL_FLOAT,
      0, 0, 0, 16,
      0, 0, 0, 0, 0,
      1, 1, 2
   },
   {
      MESA_FORMAT_LUMINANCE_FLOAT32,
      "MESA_FORMAT_LUMINANCE_FLOAT32",
      GL_ALPHA,
      GL_FLOAT,
      0, 0, 0, 0,
      32, 0, 0, 0, 0,
      1, 1, 4
   },
   {
      MESA_FORMAT_LUMINANCE_FLOAT16,
      "MESA_FORMAT_LUMINANCE_FLOAT16",
      GL_ALPHA,
      GL_FLOAT,
      0, 0, 0, 0,
      16, 0, 0, 0, 0,
      1, 1, 2
   },
   {
      MESA_FORMAT_LUMINANCE_ALPHA_FLOAT32,
      "MESA_FORMAT_LUMINANCE_ALPHA_FLOAT32",
      GL_LUMINANCE_ALPHA,
      GL_FLOAT,
      0, 0, 0, 32,
      32, 0, 0, 0, 0,
      1, 1, 8
   },
   {
      MESA_FORMAT_LUMINANCE_ALPHA_FLOAT16,
      "MESA_FORMAT_LUMINANCE_ALPHA_FLOAT16",
      GL_LUMINANCE_ALPHA,
      GL_FLOAT,
      0, 0, 0, 16,
      16, 0, 0, 0, 0,
      1, 1, 4
   },
   {
      MESA_FORMAT_INTENSITY_FLOAT32,
      "MESA_FORMAT_INTENSITY_FLOAT32",
      GL_INTENSITY,
      GL_FLOAT,
      0, 0, 0, 0,
      0, 32, 0, 0, 0,
      1, 1, 4
   },
   {
      MESA_FORMAT_INTENSITY_FLOAT16,
      "MESA_FORMAT_INTENSITY_FLOAT16",
      GL_INTENSITY,
      GL_FLOAT,
      0, 0, 0, 0,
      0, 16, 0, 0, 0,
      1, 1, 2
   },
   {
      MESA_FORMAT_DUDV8,
      "MESA_FORMAT_DUDV8",
      GL_DUDV_ATI,
      GL_SIGNED_NORMALIZED,
      0, 0, 0, 0,
      0, 0, 0, 0, 0,
      1, 1, 2
   },
   {
      MESA_FORMAT_SIGNED_RGBA8888,
      "MESA_FORMAT_SIGNED_RGBA8888",
      GL_RGBA,
      GL_SIGNED_NORMALIZED,
      8, 8, 8, 8,
      0, 0, 0, 0, 0,
      1, 1, 4
   },
   {
      MESA_FORMAT_SIGNED_RGBA8888_REV,
      "MESA_FORMAT_SIGNED_RGBA8888_REV",
      GL_RGBA,
      GL_SIGNED_NORMALIZED,
      8, 8, 8, 8,
      0, 0, 0, 0, 0,
      1, 1, 4
   },
   {
      MESA_FORMAT_SIGNED_RGBA_16,
      "MESA_FORMAT_SIGNED_RGBA_16",
      GL_RGBA,
      GL_SIGNED_NORMALIZED,
      16, 16, 16, 16,
      0, 0, 0, 0, 0,
      1, 1, 8
   }
};



static const struct gl_format_info *
_mesa_get_format_info(gl_format format)
{
   const struct gl_format_info *info = &format_info[format];
   assert(info->Name == format);
   return info;
}


/** Return string name of format (for debugging) */
const char *
_mesa_get_format_name(gl_format format)
{
   const struct gl_format_info *info = _mesa_get_format_info(format);
   ASSERT(info->BytesPerBlock);
   return info->StrName;
}



/**
 * Return bytes needed to store a block of pixels in the given format.
 * Normally, a block is 1x1 (a single pixel).  But for compressed formats
 * a block may be 4x4 or 8x4, etc.
 */
GLuint
_mesa_get_format_bytes(gl_format format)
{
   const struct gl_format_info *info = _mesa_get_format_info(format);
   ASSERT(info->BytesPerBlock);
   return info->BytesPerBlock;
}


/**
 * Return bits per component for the given format.
 * \param format  one of MESA_FORMAT_x
 * \param pname  the component, such as GL_RED_BITS, GL_TEXTURE_BLUE_BITS, etc.
 */
GLint
_mesa_get_format_bits(gl_format format, GLenum pname)
{
   const struct gl_format_info *info = _mesa_get_format_info(format);

   switch (pname) {
   case GL_RED_BITS:
   case GL_TEXTURE_RED_SIZE:
   case GL_RENDERBUFFER_RED_SIZE_EXT:
   case GL_FRAMEBUFFER_ATTACHMENT_RED_SIZE:
      return info->RedBits;
   case GL_GREEN_BITS:
   case GL_TEXTURE_GREEN_SIZE:
   case GL_RENDERBUFFER_GREEN_SIZE_EXT:
   case GL_FRAMEBUFFER_ATTACHMENT_GREEN_SIZE:
      return info->GreenBits;
   case GL_BLUE_BITS:
   case GL_TEXTURE_BLUE_SIZE:
   case GL_RENDERBUFFER_BLUE_SIZE_EXT:
   case GL_FRAMEBUFFER_ATTACHMENT_BLUE_SIZE:
      return info->BlueBits;
   case GL_ALPHA_BITS:
   case GL_TEXTURE_ALPHA_SIZE:
   case GL_RENDERBUFFER_ALPHA_SIZE_EXT:
   case GL_FRAMEBUFFER_ATTACHMENT_ALPHA_SIZE:
      return info->AlphaBits;
   case GL_TEXTURE_INTENSITY_SIZE:
      return info->IntensityBits;
   case GL_TEXTURE_LUMINANCE_SIZE:
      return info->LuminanceBits;
   case GL_INDEX_BITS:
   case GL_TEXTURE_INDEX_SIZE_EXT:
      return info->IndexBits;
   case GL_DEPTH_BITS:
   case GL_TEXTURE_DEPTH_SIZE_ARB:
   case GL_RENDERBUFFER_DEPTH_SIZE_EXT:
   case GL_FRAMEBUFFER_ATTACHMENT_DEPTH_SIZE:
      return info->DepthBits;
   case GL_STENCIL_BITS:
   case GL_TEXTURE_STENCIL_SIZE_EXT:
   case GL_RENDERBUFFER_STENCIL_SIZE_EXT:
   case GL_FRAMEBUFFER_ATTACHMENT_STENCIL_SIZE:
      return info->StencilBits;
   default:
      _mesa_problem(NULL, "bad pname in _mesa_get_format_bits()");
      return 0;
   }
}


/**
 * Return the data type (or more specifically, the data representation)
 * for the given format.
 * The return value will be one of:
 *    GL_UNSIGNED_NORMALIZED = unsigned int representing [0,1]
 *    GL_SIGNED_NORMALIZED = signed int representing [-1, 1]
 *    GL_UNSIGNED_INT = an ordinary unsigned integer
 *    GL_FLOAT = an ordinary float
 */
GLenum
_mesa_get_format_datatype(gl_format format)
{
   const struct gl_format_info *info = _mesa_get_format_info(format);
   return info->DataType;
}


/**
 * Return the basic format for the given type.  The result will be
 * one of GL_RGB, GL_RGBA, GL_ALPHA, GL_LUMINANCE, GL_LUMINANCE_ALPHA,
 * GL_INTENSITY, GL_YCBCR_MESA, GL_COLOR_INDEX, GL_DEPTH_COMPONENT,
 * GL_STENCIL_INDEX, GL_DEPTH_STENCIL.
 */
GLenum
_mesa_get_format_base_format(gl_format format)
{
   const struct gl_format_info *info = _mesa_get_format_info(format);
   return info->BaseFormat;
}


/**
 * Return the block size (in pixels) for the given format.  Normally
 * the block size is 1x1.  But compressed formats will have block sizes
 * of 4x4 or 8x4 pixels, etc.
 * \param bw  returns block width in pixels
 * \param bh  returns block height in pixels
 */
void
_mesa_get_format_block_size(gl_format format, GLuint *bw, GLuint *bh)
{
   const struct gl_format_info *info = _mesa_get_format_info(format);
   *bw = info->BlockWidth;
   *bh = info->BlockHeight;
}


/** Is the given format a compressed format? */
GLboolean
_mesa_is_format_compressed(gl_format format)
{
   const struct gl_format_info *info = _mesa_get_format_info(format);
   return info->BlockWidth > 1 || info->BlockHeight > 1;
}


/**
 * Return color encoding for given format.
 * \return GL_LINEAR or GL_SRGB
 */
GLenum
_mesa_get_format_color_encoding(gl_format format)
{
   /* XXX this info should be encoded in gl_format_info */
   switch (format) {
   case MESA_FORMAT_SRGB8:
   case MESA_FORMAT_SRGBA8:
   case MESA_FORMAT_SARGB8:
   case MESA_FORMAT_SL8:
   case MESA_FORMAT_SLA8:
   case MESA_FORMAT_SRGB_DXT1:
   case MESA_FORMAT_SRGBA_DXT1:
   case MESA_FORMAT_SRGBA_DXT3:
   case MESA_FORMAT_SRGBA_DXT5:
      return GL_SRGB;
   default:
      return GL_LINEAR;
   }
}


/**
 * Return number of bytes needed to store an image of the given size
 * in the given format.
 */
GLuint
_mesa_format_image_size(gl_format format, GLsizei width,
                        GLsizei height, GLsizei depth)
{
   const struct gl_format_info *info = _mesa_get_format_info(format);
   /* Strictly speaking, a conditional isn't needed here */
   if (info->BlockWidth > 1 || info->BlockHeight > 1) {
      /* compressed format */
      const GLuint bw = info->BlockWidth, bh = info->BlockHeight;
      const GLuint wblocks = (width + bw - 1) / bw;
      const GLuint hblocks = (height + bh - 1) / bh;
      const GLuint sz = wblocks * hblocks * info->BytesPerBlock;
      return sz;
   }
   else {
      /* non-compressed */
      const GLuint sz = width * height * depth * info->BytesPerBlock;
      return sz;
   }
}



GLint
_mesa_format_row_stride(gl_format format, GLsizei width)
{
   const struct gl_format_info *info = _mesa_get_format_info(format);
   /* Strictly speaking, a conditional isn't needed here */
   if (info->BlockWidth > 1 || info->BlockHeight > 1) {
      /* compressed format */
      const GLuint bw = info->BlockWidth;
      const GLuint wblocks = (width + bw - 1) / bw;
      const GLint stride = wblocks * info->BytesPerBlock;
      return stride;
   }
   else {
      const GLint stride = width * info->BytesPerBlock;
      return stride;
   }
}



/**
 * Do sanity checking of the format info table.
 */
void
_mesa_test_formats(void)
{
   GLuint i;

   assert(Elements(format_info) == MESA_FORMAT_COUNT);

   for (i = 0; i < MESA_FORMAT_COUNT; i++) {
      const struct gl_format_info *info = _mesa_get_format_info(i);
      assert(info);

      assert(info->Name == i);

      if (info->Name == MESA_FORMAT_NONE)
         continue;

      if (info->BlockWidth == 1 && info->BlockHeight == 1) {
         if (info->RedBits > 0) {
            GLuint t = info->RedBits + info->GreenBits
               + info->BlueBits + info->AlphaBits;
            assert(t / 8 == info->BytesPerBlock);
            (void) t;
         }
      }

      assert(info->DataType == GL_UNSIGNED_NORMALIZED ||
             info->DataType == GL_SIGNED_NORMALIZED ||
             info->DataType == GL_UNSIGNED_INT ||
             info->DataType == GL_FLOAT);

      if (info->BaseFormat == GL_RGB) {
         assert(info->RedBits > 0);
         assert(info->GreenBits > 0);
         assert(info->BlueBits > 0);
         assert(info->AlphaBits == 0);
         assert(info->LuminanceBits == 0);
         assert(info->IntensityBits == 0);
      }
      else if (info->BaseFormat == GL_RGBA) {
         assert(info->RedBits > 0);
         assert(info->GreenBits > 0);
         assert(info->BlueBits > 0);
         assert(info->AlphaBits > 0);
         assert(info->LuminanceBits == 0);
         assert(info->IntensityBits == 0);
      }
      else if (info->BaseFormat == GL_LUMINANCE) {
         assert(info->RedBits == 0);
         assert(info->GreenBits == 0);
         assert(info->BlueBits == 0);
         assert(info->AlphaBits == 0);
         assert(info->LuminanceBits > 0);
         assert(info->IntensityBits == 0);
      }
      else if (info->BaseFormat == GL_INTENSITY) {
         assert(info->RedBits == 0);
         assert(info->GreenBits == 0);
         assert(info->BlueBits == 0);
         assert(info->AlphaBits == 0);
         assert(info->LuminanceBits == 0);
         assert(info->IntensityBits > 0);
      }

   }
}



/**
 * Return datatype and number of components per texel for the given gl_format.
 * Only used for mipmap generation code.
 */
void
_mesa_format_to_type_and_comps(gl_format format,
                               GLenum *datatype, GLuint *comps)
{
   switch (format) {
   case MESA_FORMAT_RGBA8888:
   case MESA_FORMAT_RGBA8888_REV:
   case MESA_FORMAT_ARGB8888:
   case MESA_FORMAT_ARGB8888_REV:
   case MESA_FORMAT_XRGB8888:
      *datatype = GL_UNSIGNED_BYTE;
      *comps = 4;
      return;
   case MESA_FORMAT_RGB888:
   case MESA_FORMAT_BGR888:
      *datatype = GL_UNSIGNED_BYTE;
      *comps = 3;
      return;
   case MESA_FORMAT_RGB565:
   case MESA_FORMAT_RGB565_REV:
      *datatype = GL_UNSIGNED_SHORT_5_6_5;
      *comps = 3;
      return;

   case MESA_FORMAT_ARGB4444:
   case MESA_FORMAT_ARGB4444_REV:
      *datatype = GL_UNSIGNED_SHORT_4_4_4_4;
      *comps = 4;
      return;

   case MESA_FORMAT_ARGB1555:
   case MESA_FORMAT_ARGB1555_REV:
      *datatype = GL_UNSIGNED_SHORT_1_5_5_5_REV;
      *comps = 4;
      return;

   case MESA_FORMAT_AL88:
   case MESA_FORMAT_AL88_REV:
      *datatype = GL_UNSIGNED_BYTE;
      *comps = 2;
      return;

   case MESA_FORMAT_AL1616:
   case MESA_FORMAT_AL1616_REV:
      *datatype = GL_UNSIGNED_SHORT;
      *comps = 2;
      return;

   case MESA_FORMAT_RGB332:
      *datatype = GL_UNSIGNED_BYTE_3_3_2;
      *comps = 3;
      return;

   case MESA_FORMAT_A8:
   case MESA_FORMAT_L8:
   case MESA_FORMAT_I8:
   case MESA_FORMAT_CI8:
      *datatype = GL_UNSIGNED_BYTE;
      *comps = 1;
      return;

   case MESA_FORMAT_YCBCR:
   case MESA_FORMAT_YCBCR_REV:
      *datatype = GL_UNSIGNED_SHORT;
      *comps = 2;
      return;

   case MESA_FORMAT_Z24_S8:
      *datatype = GL_UNSIGNED_INT;
      *comps = 1; /* XXX OK? */
      return;

   case MESA_FORMAT_S8_Z24:
      *datatype = GL_UNSIGNED_INT;
      *comps = 1; /* XXX OK? */
      return;

   case MESA_FORMAT_Z16:
      *datatype = GL_UNSIGNED_SHORT;
      *comps = 1;
      return;

   case MESA_FORMAT_X8_Z24:
      *datatype = GL_UNSIGNED_INT;
      *comps = 1;
      return;

   case MESA_FORMAT_Z24_X8:
      *datatype = GL_UNSIGNED_INT;
      *comps = 1;
      return;

   case MESA_FORMAT_Z32:
      *datatype = GL_UNSIGNED_INT;
      *comps = 1;
      return;

   case MESA_FORMAT_DUDV8:
      *datatype = GL_BYTE;
      *comps = 2;
      return;

   case MESA_FORMAT_SIGNED_RGBA8888:
   case MESA_FORMAT_SIGNED_RGBA8888_REV:
      *datatype = GL_BYTE;
      *comps = 4;
      return;
   case MESA_FORMAT_SIGNED_RGBA_16:
      *datatype = GL_SHORT;
      *comps = 4;
      return;

#if FEATURE_EXT_texture_sRGB
   case MESA_FORMAT_SRGB8:
      *datatype = GL_UNSIGNED_BYTE;
      *comps = 3;
      return;
   case MESA_FORMAT_SRGBA8:
   case MESA_FORMAT_SARGB8:
      *datatype = GL_UNSIGNED_BYTE;
      *comps = 4;
      return;
   case MESA_FORMAT_SL8:
      *datatype = GL_UNSIGNED_BYTE;
      *comps = 1;
      return;
   case MESA_FORMAT_SLA8:
      *datatype = GL_UNSIGNED_BYTE;
      *comps = 2;
      return;
#endif

#if FEATURE_texture_fxt1
   case MESA_FORMAT_RGB_FXT1:
   case MESA_FORMAT_RGBA_FXT1:
#endif
#if FEATURE_texture_s3tc
   case MESA_FORMAT_RGB_DXT1:
   case MESA_FORMAT_RGBA_DXT1:
   case MESA_FORMAT_RGBA_DXT3:
   case MESA_FORMAT_RGBA_DXT5:
#if FEATURE_EXT_texture_sRGB
   case MESA_FORMAT_SRGB_DXT1:
   case MESA_FORMAT_SRGBA_DXT1:
   case MESA_FORMAT_SRGBA_DXT3:
   case MESA_FORMAT_SRGBA_DXT5:
#endif
      /* XXX generate error instead? */
      *datatype = GL_UNSIGNED_BYTE;
      *comps = 0;
      return;
#endif

   case MESA_FORMAT_RGBA_FLOAT32:
      *datatype = GL_FLOAT;
      *comps = 4;
      return;
   case MESA_FORMAT_RGBA_FLOAT16:
      *datatype = GL_HALF_FLOAT_ARB;
      *comps = 4;
      return;
   case MESA_FORMAT_RGB_FLOAT32:
      *datatype = GL_FLOAT;
      *comps = 3;
      return;
   case MESA_FORMAT_RGB_FLOAT16:
      *datatype = GL_HALF_FLOAT_ARB;
      *comps = 3;
      return;
   case MESA_FORMAT_LUMINANCE_ALPHA_FLOAT32:
      *datatype = GL_FLOAT;
      *comps = 2;
      return;
   case MESA_FORMAT_LUMINANCE_ALPHA_FLOAT16:
      *datatype = GL_HALF_FLOAT_ARB;
      *comps = 2;
      return;
   case MESA_FORMAT_ALPHA_FLOAT32:
   case MESA_FORMAT_LUMINANCE_FLOAT32:
   case MESA_FORMAT_INTENSITY_FLOAT32:
      *datatype = GL_FLOAT;
      *comps = 1;
      return;
   case MESA_FORMAT_ALPHA_FLOAT16:
   case MESA_FORMAT_LUMINANCE_FLOAT16:
   case MESA_FORMAT_INTENSITY_FLOAT16:
      *datatype = GL_HALF_FLOAT_ARB;
      *comps = 1;
      return;

   default:
      _mesa_problem(NULL, "bad format in _mesa_format_to_type_and_comps");
      *datatype = 0;
      *comps = 1;
   }
}