summaryrefslogtreecommitdiffstats
path: root/src/mesa/drivers/glide/fxapi.c
blob: 2465ce37bc9fce095afae3824afda4cebca4d193 (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
/* -*- mode: C; tab-width:8;  -*- */

/*
 * Mesa 3-D graphics library
 * Version:  3.3
 *
 * Copyright (C) 1999-2000  Brian Paul   All Rights Reserved.
 *
 * 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.
 *
 *
 * Original Mesa / 3Dfx device driver (C) 1999 David Bucciarelli, by the
 * terms stated above.
 *
 * Thank you for your contribution, David!
 *
 * Please make note of the above copyright/license statement.  If you
 * contributed code or bug fixes to this code under the previous (GNU
 * Library) license and object to the new license, your code will be
 * removed at your request.  Please see the Mesa docs/COPYRIGHT file
 * for more information.
 *
 * Additional Mesa/3Dfx driver developers:
 *   Daryll Strauss <daryll@precisioninsight.com>
 *   Keith Whitwell <keith@precisioninsight.com>
 *
 * See fxapi.h for more revision/author details.
 */


/* fxapi.c - 3Dfx VooDoo/Mesa interface */


/********************************************************************
 *
 * Function names:
 *  fxMesa....     (The driver API)
 *  fxDD....       (Mesa device driver functions)
 *  fxTM....       (Texture manager functions)
 *  fxSetup....    (Voodoo units setup functions)
 *  fx....         (Internal driver functions)
 *
 * Data type names:
 *  fxMesa....     (Public driver data types)
 *  tfx....        (Private driver data types)
 *
 ********************************************************************
 *
 * V0.30 - David Bucciarelli (davibu@tin.it) Humanware s.r.l.
 *         - introduced a new MESA_GLX_FX related behavior
 *         - the Glide fog table was built in a wrong way (using
 *           gu* Glide function). Added the code for building the
 *           table following the OpenGL specs. Thanks to Steve Baker
 *           for highlighting the problem.
 *         - fixed few problems in my and Keith's fxDDClear code
 *         - merged my code with the Keith's one
 *         - used the new BlendFunc Mesa device driver function 
 *         - used the new AlphaFunc Mesa device driver function 
 *         - used the new Enable Mesa device driver function 
 *         - fixed a bug related to fog in the Mesa core. Fog
 *           were applied two times: at vertex level and at fragment
 *           level (thanks to Steve Baker for reporting the problem)
 *         - glColorMask(GL_FALSE,GL_FALSE,GL_FALSE,GL_FALSE) now works
 *           (thanks to Jiri Pop for reporting the problem)
 *         - the driver works fine with OpenGL Unreal
 *         - fixed a bug in the Mesa core clipping code (related
 *           to the q texture coordinate)
 *         - introduced the support for the q texture coordinate
 *
 *         Keith Whitwell (keithw@cableinet.co.uk)
 *         - optimized the driver and written all the new code
 *           required by the new Mesa-3.1 device driver API
 *           and by the new Mesa-3.1 core changes
 *         - written the cva support and many other stuff
 *
 *         Brian Paul (brian_paul@avid.com) Avid Technology
 *         - fixed display list share bug for MESA_GLX_FX = window/fullscreen
 *         - fixed glClear/gl...Mask related problem
 *
 *         Bert Schoenwaelder (bert@prinz-atm.CS.Uni-Magdeburg.De)
 *         - the driver is now able to sleep when waiting for the completation
 *           of multiple swapbuffer operations instead of wasting
 *           CPU time (NOTE: you must uncomment the lines in the
 *           fxMesaSwapBuffers function in order to enable this option)
 *
 *         Eero Pajarre (epajarre@koti.tpo.fi)
 *         - enabled the macro FLOAT_COLOR_TO_UBYTE_COLOR under
 *           windows
 *         - written an asm x86 optimized float->integer conversions
 *           for windows
 *
 *         Theodore Jump (tjump@cais.com)
 *         - fixed a small problem in the __wglMonitor function of the
 *           wgl emulator
 *         - written the in-window-rendering hack support for windows
 *           and Vooodoo1/2 cards
 *
 * V0.29 - David Bucciarelli (tech.hmw@plus.it) Humanware s.r.l.
 *         - included in Mesa-3.0
 *         - now glGetString(GL_RENDERER) returns more information
 *           about the hardware configuration: "Mesa Glide <version>
 *           <Voodoo_Graphics|Voodoo_Rush|UNKNOWN> <num> CARD/<num> FB/
 *           <num> TM/<num> TMU/<NOSLI|SLI>"
 *           where: <num> CARD is the card used for the current context,
 *           <num> FB is the number of MB for the framebuffer,
 *           <num> TM is the number of MB for the texture memory,
 *           <num> TMU is the number of TMU. You can try to run
 *           Mesa/demos/glinfo in order to have an example of the
 *           output
 *         - fixed a problem of the WGL emulator with the
 *           OpenGL Optimizer 1.1 (thanks to Erwin Coumans for
 *           the bug report)
 *         - fixed some bug in the fxwgl.c code (thanks to  
 *           Peter Pettersson for a patch and a bug report)
 *
 *         Theodore Jump (tjump@cais.com)
 *         - written the SST_DUALHEAD support in the WGL emulator
 *
 *         Daryll Strauss (daryll@harlot.rb.ca.us)
 *         - fixed the Voodoo Rush support for the in window rendering
 *
 * V0.28 - David Bucciarelli (tech.hmw@plus.it) Humanware s.r.l.
 *         - the only supported multitexture functions are GL_MODULATE
 *           for texture set 0 and GL_MODULATE for texture set 1. In
 *           all other cases, the driver falls back to pure software
 *           rendering
 *         - written the support for the new  GL_EXT_multitexture
 *         - written the DD_MAX_TEXTURE_COORD_SETS support in the
 *           fxDDGetParameteri() function
 *         - the driver falls back to pure software rendering when
 *           texture mapping function is GL_BLEND
 *
 * V0.27 - David Bucciarelli (tech.hmw@plus.it) Humanware s.r.l.
 *         - inluded in the Mesa-3.0beta5
 *         - written a smal extension (GL_FXMESA_global_texture_lod_bias) in
 *           order to expose the LOD bias related Glide function
 *         - fixed a bug fxDDWriteMonoRGBAPixels()
 *         - the driver is now able to fallback to software rendering in
 *           any case not directly supported by the hardware
 *         - written the support for enabling/disabling dithering
 *         - the in-window-rendering hack now works with any X11 screen
 *           depth
 *         - fixed a problem related to color/depth/alpha buffer clears
 *         - fixed a problem when clearing buffer for a context with the
 *           alpha buffer
 *         - fixed a problem in the fxTMReloadSubMipMapLevel() function,
 *           I have forget a "break;" (thanks to Joe Waters for the bug report)
 *         - fixed a problem in the color format for the in window
 *           rendering hack
 *         - written the fxDDReadRGBAPixels function
 *         - written the fxDDDepthTestPixelsGeneric function
 *         - written the fxDDDepthTestSpanGeneric function
 *         - written the fxDDWriteMonoRGBAPixels function
 *         - written the fxDDWriteRGBAPixels function
 *         - removed the multitexture emulation code for Voodoo board
 *         with only one TMU
 *
 *         Chris Prince <cprince@cs.washington.edu>
 *         - fixed a new bug in the wglUseFontBitmaps code
 *
 *         Ralf Knoesel (rknoesel@Stormfront.com)
 *         - fixed a bug in the wglUseFontBitmaps code
 *
 *         Rune Hasvold (runeh@ifi.uio.no)
 *         - fixed a problem related to the aux usage in the fxBestResolution
 *           function
 *         - fixed the order of pixel formats in the WGL emulator
 *
 *         Fredrik Hubinette (hubbe@hubbe.net)
 *         - the driver shutdown the Glide for most common signals
 *
 * V0.26 - David Bucciarelli (tech.hmw@plus.it) Humanware s.r.l.
 *         - included in the Mesa-3.0beta4
 *         - fixed a problem related to a my optimization for the Rune's
 *           pixel-span optimization
 *         - fixed a problem related to fxDDSetNearFar() and ctx->ProjectionMatrixType
 *           (thanks to Ben "Ctrl-Alt-Delete" and the Raul Alonso's ssystem)
 *         - fixed a small bug in the Rune's pixel-span optimization
 *         - fixed a problem with GL_CCW (thanks to Curt Olson for and example
 *           of the problem)
 *         - grVertex setup code is now ready for the internal thread support
 *         - fixed a no used optimization with clipped vertices in
 *           grVertex setup code
 *         - fixed a problem in the GL_LIGHT_MODEL_TWO_SIDE support (thanks
 *           to Patrick H. Madden for a complete example of the bug)
 *
 *         Rune Hasvold (runeh@ifi.uio.no)
 *         - highly optimized the driver functions for writing pixel
 *           span (2-3 times faster !)
 *
 *         Axel W. Volley (volley@acm.org) Krauss-Maffei Wehrtechnik
 *         - written the fxDDReadDepthSpanFloat() and fxDDReadDepthSpanInt()
 *           functions
 *
 * V0.25 - David Bucciarelli (tech.hmw@plus.it) Humanware s.r.l.
 *         - fixed a problem with Voodoo boards with only one TMU
 *         - fixed a bug in the fxMesaCreateContext()
 *         - now the GL_FRONT_AND_BACK works fine also with
 *           the alpha buffer and/or antialiasing
 *         - written the support for GL_FRONT_AND_BACK drawing but
 *           it doesn't works with the alpha buffer and/or antialiasing
 *         - fixed some bug in the Mesa core for glCopyTexSubImage
 *           and glCopyTexImage functions (thanks to Mike Connell
 *           for an example of the problem)
 *         - make some small optimizations in the Mesa core in order
 *           to save same driver call and state change for not very
 *           well written applications
 *         - introduced the NEW_DRVSTATE and make other optimizations
 *           for minimizing state changes
 *         - made a lot of optimizations in order to minimize state
 *           changes
 *         - it isn't more possible to create a context with the
 *           depth buffer and the stancil buffer (it isn't yet supported)
 *         - now the partial support for the Multitexture extension
 *           works with Quake2 for windows
 *         - vertex snap is not longer used for the Voodoo2 (FX_V2
 *           must be defined)
 *         - done a lot of cleanup in the fxsetup.c file
 *         - now the partial support for the Multitexture extension
 *           works with GLQuake for windows
 *
 *         Dieter Nuetzel (nuetzel@kogs.informatik.uni-hamburg.de) University of Hamburg
 *         - fixed a problem in the asm code for Linux of the fxvsetup.c file
 *           highlighted by the binutils-2.8.1.0.29. 'fildw' asm instruction
 *           changed in 'fild'
 *
 *         Kevin Hester (kevinh@glassworks.net)
 *         - written the wglUseFontBitmaps() function in the WGL emulator
 *
 * V0.24 - David Bucciarelli (tech.hmw@plus.it) Humanware s.r.l.
 *         - now the drive always uses per fragment fog
 *         - written a small optimization in the points drawing function
 *         - written the support for trilinear filtering with 2 TMUs
 *         - written the first partial support for the Multitexture extension.
 *           This task is quite hard because the color combine units work after
 *           the two texture combine units and not before as required by the 
 *           Multitexture extension
 *         - written a workaround in fxBestResolution() in order to solve a
 *           problem with bzflag (it asks for 1x1 window !)
 *         - changed the fxBestResolution() behavior. It now returns the larger
 *           screen resolution supported by the hardware (instead of 640x480)
 *           when it is unable to find an appropriate resolution that is large
 *           enough for the requested size 
 *         - the driver is now able to use also the texture memory attached to
 *           second TMU
 *         - the texture memory manager is now able to work with two TMUs and
 *           store texture maps in the memory attached to TMU0, TMU1 or to split
 *           the mimpmap levels across TMUs in order to support trilinear filtering
 *         - I have bought a Voodoo2 board !
 *         - the amount of frambuffer ram is now doubled when an SLI configuration
 *           is detected
 *         - solved a problem related to the fxDDTexParam() and fxTexInvalidate()
 *           functions (thanks to Rune Hasvold for highlighting the problem)
 *         - done some cleanup in the fxvsetup.c file, written
 *           the FXVSETUP_FUNC macro
 *         - done a lot of cleanup in data types and field names
 *
 *         Rune Hasvold (runeh@ifi.uio.no)
 *         - written the support for a right management of the auxiliary buffer.
 *           You can now use an 800x600 screen without the depth and alpha
 *           buffer
 *         - written the support for a new pixel format (without the depth
 *           and alpha buffer) in the WGL emulator
 *         - fixed a bug in the window version of the GLUT (it was ever asking
 *           for depth buffer)
 *
 * V0.23 - David Bucciarelli (tech.hmw@plus.it) Humanware s.r.l.
 *         - included in the Mesa-3.0beta2 release
 *         - written the support for the OpenGL 1.2 GL_TEXTURE_BASE_LEVEL
 *           and GL_TEXTURE_MAX_LEVEL
 *         - rewritten several functions for a more clean support of texture
 *           mapping and in order to solve some bug
 *         - the accumulation buffer works (it is  bit slow beacuase it requires
 *           to read/write from/to the Voodoo frame buffer but it works)
 *         - fixed a bug in the fxDDReadRGBASpan driver function (the R and
 *           B channels were read in the wrong order). Thanks to Jason Heym
 *           for highlighting the problem
 *         - written the support for multiple contexts on multiple boards.
 *           you can now use the Mesa/Voodoo with multiple Voodoo Graphics
 *           boards (for example with multiple screens or an HMD)
 *         - the fxBestResolution() now check all available resolutions
 *           and it is able to check the amount of framebuffer memory
 *           before return a resolution
 *         - modified the GLX/X11 driver in order to support all the
 *           resolution available
 *         - changed all function names. They should be now a bit more
 *           readable
 *         - written the Glide grVertex setup code for two TMU or
 *           for Multitexture support with emulationa dn one TMU
 *         - written the support for the new Mesa driver
 *           function GetParametri
 *         - small optimization/clean up in the texbind() function
 *         - fixed a FPU precision problem for glOrtho and texture
 *           mapping (thanks to Antti Juhani Huovilainen for an example
 *           of the problem)
 *         - written some small SGI OpenGL emulation code for the wgl,
 *           the OpenGL Optimizer and Cosmo3D work fine under windows !
 *         - moved the point/line/triangle/quad support in the fxmesa7.c
 *         - fixed a bug in the clear_color_depth() (thanks to Henk Kok
 *           for an example of the problem)
 *         - written a small workaround for Linux GLQuake, it asks
 *           for the alpha buffer and the depth buffer at the some time
 *           (but it never uses the alpha buffer)
 *         - checked the antialiasing points, lines and polygons support.
 *           It works fine
 *         - written the support for standard OpenGL antialiasing using
 *           blending. Lines support works fine (tested with BZflag)
 *           while I have still to check the polygons and points support
 *         - written the support for the alpha buffer. The driver is now
 *           able to use the Voodoo auxiliary buffer as an alpha buffer
 *           instead of a depth buffer. Also all the OpenGL blending
 *           modes are now supported. But you can't request a context
 *           with an alpha buffer AND a depth buffer at the some time
 *           (this is an hardware limitation)
 *         - written the support for switching between the fullscreen
 *           rendering and the in-window-rendering hack on the fly
 *
 *         Rune Hasvold (runeh@ifi.uio.no)
 *         - fixed a bug in the texparam() function
 *
 *         Brian Paul (brianp@elastic.avid.com) Avid Technology
 *         - sources accomodated for the new Mesa 3.0beta1
 *
 * V0.22 - David Bucciarelli (tech.hmw@plus.it) Humanware s.r.l.
 *         - included with some v0.23 bug fix in the final release
 *           of the Mesa-2.6
 *         - written the support for the MESA_WGL_FX env. var. but
 *           not tested because I have only Voodoo Graphics boards
 *         - fixed a bug in the backface culling code
 *           (thanks to David Farrell for an example of the problem)
 *         - fixed the "Quake2 elevator" bug
 *         - GL_POLYGONS with 3/4 vertices are now drawn as
 *           GL_TRIANLGES/GL_QUADS (a small optimization for GLQuake)
 *         - fixed a bug in fxmesa6.h for GL_LINE_LOOP
 *         - fixed a NearFarStack bug in the Mesa when applications
 *           directly call glLoadMatrix to load a projection matrix 
 *         - done some cleanup in the fxmesa2.c file
 *         - the driver no longer translates the texture maps
 *           when the Mesa internal format and the Voodoo
 *           format are the some (usefull for 1 byte texture maps
 *           where the driver can directly use the Mesa texture
 *           map). Also the amount of used memory is halfed
 *         - fixed a bug for GL_DECAL and GL_RGBA
 *         - fixed a bug in the clear_color_depth()
 *         - tested the v0.22 with the Mesa-2.6beta2. Impressive
 *           performances improvement thanks to the new Josh's
 *           asm code (+10fps in the isosurf demo, +5fps in GLQuake
 *           TIMEREFRESH)
 *         - written a optimized version of the RenderVB Mesa driver
 *           function. The Voodoo driver is now able to upload polygons
 *           in the most common cases at a very good speed. Good
 *           performance improvement for large set of small polygons
 *         - optimized the asm code for setting up the color information
 *           in the Glide grVertex structure
 *         - fixed a bug in the fxmesa2.c asm code (the ClipMask[]
 *           wasn't working)
 *
 *         Josh Vanderhoof (joshv@planet.net)
 *         - removed the flush() function because it isn't required
 *         - limited the maximum number of swapbuffers in the Voodoo
 *           commands FIFO (controlled by the env. var. MESA_FX_SWAP_PENDING)
 *
 *         Holger Kleemiss (holger.kleemiss@metronet.de) STN Atlas Elektronik GmbH
 *         - applied some patch for the Voodoo Rush
 *
 * V0.21 - David Bucciarelli (tech.hmw@plus.it) Humanware s.r.l.
 *         - the driver is now able to take advantage of the ClipMask[],
 *           ClipOrMask and ClipAndMask information also under Windows
 *         - introduced a new function in the Mesa driver interface
 *           ClearColorAndDepth(). Now the glClear() function is
 *           2 times faster (!) when you have to clear the color buffer
 *           and the depth buffer at some time
 *         - written the first version of the fxRenderVB() driver
 *           function
 *         - optimized the glTexImage() path
 *         - removed the fxMesaTextureUsePalette() support
 *         - fixed a bug in the points support (thanks to David Farrell
 *           for an example of the problem)
 *         - written the optimized path for glSubTexImage(),
 *           introduced a new function in the Mesa driver interface
 *           TexSubImage(...)
 *         - fixed a bug for glColorMask and glDepthMask
 *         - the wbuffer is not more used. The Voodoo driver uses
 *           a standard 16bit zbuffer in all cases. It is more consistent
 *           and now GLQuake and GLQuake2test work also with a GL_ZTRICK 0
 *         - the driver is now able to take advantage of the ClipMask[],
 *           ClipOrMask and ClipAndMask information (under Linux);
 *         - rewritten the setup_fx_units() function, now the texture
 *           mapping support is compliant to the OpenGL specs (GL_BLEND
 *           support is still missing). The LinuxGLQuake console correctly
 *           fade in/out and transparent water of GLQuake2test works fine
 *         - written the support for the env. var. FX_GLIDE_SWAPINTERVAL
 *         - found a bug in the Mesa core. There is a roundup problem for
 *           color values out of the [0.0,1.0] range
 *
 *         Wonko <matt@khm.de>
 *         - fixed a Voodoo Rush related problem in the fxwgl.c
 *
 *         Daryll Strauss <daryll@harlot.rb.ca.us>
 *         - written the scissor test support
 *
 * V0.20 - David Bucciarelli (tech.hmw@plus.it) Humanware s.r.l.
 *         - written the closetmmanger() function in order to free all the memory
 *           allocated by the Texture Memory Manager (it will be useful
 *           when the support for multiple contexts/boards will be ready)
 *         - now the Voodoo driver runs without printing any information,
 *           define the env. var. MESA_FX_INFO if you want to read some
 *           information about the hardware and some statistic
 *         - written a small workaround for the "GLQuake multiplayer white box bug"
 *           in the setup_fx_units() funxtions. I'm already rewriting
 *           this function because it is the source of nearly all the current
 *           Voodoo driver problems
 *         - fixed the GLQuake texture misalignment problem (the texture
 *           coordinates must be scaled between 0.0 and 256.0 and not
 *           between 0.0 and 255.0)
 *         - written the support for the GL_EXT_shared_texture_palette
 *         - some small change for supporting the automatic building of the
 *           OpenGL32.dll under the Windows platform
 *         - the redefinition of a mipmap level is now a LOT faster. This path
 *           is used by GLQuake for dynamic lighting with some call to glTexSubImage2D()
 *         - the texture memory is now managed a set of 2MB blocks so
 *           texture maps can't be allocated on a 2MB boundary. The new Pure3D
 *           needs this kind of support (and probably any other Voodoo Graphics
 *           board with more than 2MB of texture memory)
 *
 *         Brian Paul (brianp@elastic.avid.com) Avid Technology
 *         - added write_monocolor_span(), fixed bug in write_color_span()
 *         - added test for stenciling in choosepoint/line/triangle functions
 *
 *         Joe Waters (falc@attila.aegistech.com) Aegis
 *         - written the support for the env. var. SST_SCREENREFRESH
 *
 * V0.19 - David Bucciarelli (tech.hmw@plus.it) Humanware s.r.l.
 *         - written the 3Dfx Global Palette extension for GLQuake
 *         - written the support for the GL_EXT_paletted_texture (it works only with GL_RGBA
 *           palettes and the alpha value is ignored ... this is a limitation of the
 *           the current Glide version and Voodoo hardware)
 *         - fixed the amount of memory allocated for 8bit textures
 *         - merged the under construction v0.19 driver with the Mesa 2.5
 *         - finally written the support for deleting textures
 *         - introduced a new powerful texture memory manager: the texture memory
 *           is used as a cache of the set of all defined texture maps. You can
 *           now define several MB of texture maps also with a 2MB of texture memory
 *           (the texture memory manager will do automatically all the swap out/swap in
 *           work). The new texture memory manager has also
 *           solved a lot of other bugs/no specs compliance/problems
 *           related to the texture memory usage. The texture
 *           manager code is inside the new fxmesa3.c file
 *         - broken the fxmesa.c file in two files (fxmesa1.c and fxmesa2.c)
 *           and done some code cleanup
 *         - now is possible to redefine texture mipmap levels already defined
 *         - fixed a problem with the amount of texture memory allocated for textures
 *           with not all mipmap levels defined
 *         - fixed a small problem with single buffer rendering
 *
 *         Brian Paul (brianp@elastic.avid.com) Avid Technology
 *         - read/write_color_span() now use front/back buffer correctly
 *         - create GLvisual with 5,6,5 bits per pixel, not 8,8,8
 *         - removed a few ^M characters from fxmesa2.c file
 *
 * V0.18 - David Bucciarelli (tech.hmw@plus.it) Humanware s.r.l.
 *         - the Mesa-2.4beta3 is finally using the driver quads support (the
 *           previous Mesa versions have never taken any advantage from the quads support !)
 *         - tested with the Glide 2.4 for Win
 *         - ported all asm code to Linux
 *         - ported the v0.18 to Linux (without asm code)
 *         - back to Linux !!!
 *         - optimized the SETUP macro (no more vertex snap for points and lines)
 *         - optimized the SETUP macro (added one argument)
 *         - the Mesa/Voodoo is now 20/30% for points, lines and small triangles !
 *         - performance improvement setting VBSIZE to 72 
 *         - the GrVertex texture code is now written in asm
 *         - the GrVertex zbuffer code is now written in asm
 *         - the GrVertex wbuffer code is now written in asm
 *         - the GrVertex gouraud code is now written in asm
 *         - the GrVertex snap code is now written in asm
 *         - changed the 8bit compressed texture maps in 8bit palette texture maps
 *           support (it has the some advantage of compressed texture maps without the
 *           problem of a fixed NCC table for all mipmap levels)
 *         - written the support for 8bit compressed texture maps (but texture maps with
 *           more than one mipmap level aren't working fine)
 *         - finnaly everthing is working fine in MesaQuake !
 *         - fixed a bug in the computation of texture mapping coordinates (I have found
 *           the bug thanks to MesaQuake !)
 *         - written the GL_REPLACE support (mainly for MesaQuake)
 *         - written the support for textures with not all mipmap levels defined
 *         - rewritten all the Texture memory stuff
 *         - written the MesaQuake support (define MESAQUAKE)
 *         - working with a ZBuffer if glOrtho or not int the default glDepthRange,
 *           otherwise working with the WBuffer
 *         written the glDepthRange support
 *
 *         Diego Picciani (d.picciani@novacomp.it) Nova Computer s.r.l.
 *         - written the fxCloseHardware() and the fxQuaryHardware() (mainly
 *           for the VoodooWGL emulator)
 *
 *         Brian Paul (brianp@elastic.avid.com) Avid Technology
 *         - implemented read/write_color_span() so glRead/DrawPixels() works
 *         - now needs Glide 2.3 or later.  Removed GLIDE_FULL_SCREEN and call to grSstOpen()
 *
 * V0.17 - David Bucciarelli (tech.hmw@plus.it) Humanware s.r.l.
 *         - optimized the bitmap support (66% faster)
 *         - tested with the Mesa 2.3beta2
 *
 *         Diego Picciani (d.picciani@novacomp.it) Nova Computer s.r.l.
 *         - solved a problem with the drawbitmap() and the Voodoo Rush
 *           (GR_ORIGIN_LOWER_LEFT did not work with the Stingray)
 *
 *         Brian Paul (brianp@elastic.avid.com) Avid Technology
 *         - linux stuff
 *         - general code clean-up
 *         - added attribList parameter to fxMesaCreateContext()
 *         - single buffering works now
 *         - VB colors are now GLubytes, removed ColorShift stuff
 *
 *         Paul Metzger
 *         - linux stuff
 *
 * V0.16 - David Bucciarelli (tech.hmw@plus.it) Humanware s.r.l.
 *         - written the quadfunc support (no performance improvement)
 *         - written the support for the new Mesa 2.3beta1 driver interface (Wow ! It is faaaster)
 *         - rewritten the glBitmap support for the Glide 2.3 (~35% slower !)
 *         - written the glBitmap support for the most common case (fonts)
 *
 *         Jack Palevich
 *         - Glide 2.3 porting
 *
 *         Diego Picciani (d.picciani@novacomp.it) Nova Computer s.r.l.
 *         - extended the fxMesaCreateContext() and fxMesaCreateBestContext()
 *           functions in order to support also the Voodoo Rush
 *         - tested with the Hercules Stingray 128/3D (The rendering in a window works !)
 *
 * V0.15 - David Bucciarelli (tech.hmw@plus.it) Humanware s.r.l.
 *         - written the GL_LUMINANCE_ALPHA support
 *         - written the GL_ALPHA support
 *         - written the GL_LUMINANCE support
 *         - now SETUP correctly set color for mono color sequences
 *         - written the 9x1,10x1,...,1x9,1x10,... texture map ratio support
 *         - written the no square texture map support
 *         - the fog table is no more rebuilt inside setup_fx_units() each time
 *
 *         Henri Fousse (arnaud@pobox.oleane.com) Thomson Training & Simulation
 *         - written (not yet finished: no texture mapping) support for glOrtho
 *         - some change to setup functions
 *         - the fog support is now fully compatible with the standard OpenGL
 *         - rewritten several parts of the driver in order to take
 *           advantage of meshes (40% faster !!!)
 *
 * V0.14 - David Bucciarelli (tech.hmw@plus.it) Humanware s.r.l.
 *         - now glAlphaFunc() works
 *         - now glDepthMask() works
 *         - solved a mipmap problem when using more than one texture
 *         - moved ti, texid and wscale inside the fxMesaContext (now we can
 *           easy support more ctx and more boards)
 *         - the management of the fxMesaContext was completly broken !
 *         - solved several problems about Alpha and texture Alpha
 *         - 4 (RGBA) texture channels supported
 *         - setting the default color to white
 *
 *         Henri Fousse (arnaud@pobox.oleane.com) Thomson Training & Simulation
 *         - small change to fxMesaCreateContext() and fxMesaMakeCurrent()
 *         - written the fog support
 *         - setting the default clear color to black
 *         - written cleangraphics() for the onexit() function
 *         - written fxMesaCreateBestContext()
 *
 * V0.13 - David Bucciarelli (tech.hmw@plus.it) Humanware s.r.l.
 *         - now glBlendFunc() works for all glBlendFunc without DST_ALPHA
 *           (because the alpha buffer is not yet implemented) 
 *         - now fxMesaCreateContext() accept resolution and refresh rate
 *         - fixed a bug for texture mapping: the w (alias z) must be set
 *           also without depth buffer
 *         - fixed a bug for texture image with width!=256
 *         - written texparam()
 *         - written all point, line and triangle functions for all possible supported
 *           contexts and the driver is slight faster with points, lines and small triangles
 *         - fixed a small bug in fx/fxmesa.h (glOrtho)
 *
 * V0.12 - David Bucciarelli (tech.hmw@plus.it) Humanware s.r.l.
 *         - glDepthFunc supported
 *         - introduced a trick to discover the far plane distance
 *           (see fxMesaSetFar and fx/fxmesa.h)
 *         - now the wbuffer works with homogeneous coordinate (and it
 *           doesn't work with a glOrtho projection :)
 *         - solved several problems with homogeneous coordinate and texture mapping
 *         - fixed a bug in all line functions
 *         - fixed a clear framebuffer bug
 *         - solved a display list/teximg problem (but use
 *           glBindTexture: it is several times faster)
 *
 * V0.11 - David Bucciarelli (tech.hmw@plus.it) Humanware s.r.l.
 *         - introduced texture mapping support (not yet finished !)
 *         - tested with Mesa2.2b6
 *         - the driver is faster 
 *         - written glFlush/glFinish
 *         - the driver print a lot of info about the Glide lib
 *
 * v0.1  - David Bucciarelli (tech.hmw@plus.it) Humanware s.r.l.
 *         - Initial revision
 *
 */


#ifdef HAVE_CONFIG_H
#include "conf.h"
#endif

#if defined(FX)
#include "fxdrv.h"

fxMesaContext fxMesaCurrentCtx=NULL;

/*
 * Status of 3Dfx hardware initialization
 */

static int glbGlideInitialized=0;
static int glb3DfxPresent=0;
static int glbTotNumCtx=0;

GrHwConfiguration glbHWConfig;
int glbCurrentBoard=0;


#if defined(__WIN32__)
static int cleangraphics(void)
{
  glbTotNumCtx=1;
  fxMesaDestroyContext(fxMesaCurrentCtx);

  return 0;
}
#elif defined(__linux__)
static void cleangraphics(void)
{
  glbTotNumCtx=1;
  fxMesaDestroyContext(fxMesaCurrentCtx);
}

static void cleangraphics_handler(int s)
{
  fprintf(stderr,"fxmesa: Received a not handled signal %d\n",s);

  cleangraphics();
/*    abort(); */
  exit(1);
}
#endif


/*
 * Select the Voodoo board to use when creating
 * a new context.
 */
GLboolean GLAPIENTRY fxMesaSelectCurrentBoard(int n)
{
  fxQueryHardware();

  if((n<0) || (n>=glbHWConfig.num_sst))
    return GL_FALSE;

  glbCurrentBoard=n;

  return GL_TRUE;
}


fxMesaContext GLAPIENTRY fxMesaGetCurrentContext(void)
{
  return fxMesaCurrentCtx;
}


void GLAPIENTRY fxMesaSetNearFar(GLfloat n, GLfloat f)
{
  if(fxMesaCurrentCtx)
    fxDDSetNearFar(fxMesaCurrentCtx->glCtx,n,f);
}


/*
 * The extension GL_FXMESA_global_texture_lod_bias
 */
/* XXX this function may soon go away in favor of GL_EXT_texture_lod_bias */
extern void GLAPIENTRY glGlobalTextureLODBiasFXMESA(GLfloat biasVal);
void GLAPIENTRY glGlobalTextureLODBiasFXMESA(GLfloat biasVal)
{
  grTexLodBiasValue(GR_TMU0,biasVal);

  if(fxMesaCurrentCtx->haveTwoTMUs)
    grTexLodBiasValue(GR_TMU1,biasVal);
}


/*
 * The 3Dfx Global Palette extension for GLQuake.
 * More a trick than a real extesion, use the shared global
 * palette extension. 
 */
extern void GLAPIENTRY gl3DfxSetPaletteEXT(GLuint *pal); /* silence warning */
void GLAPIENTRY gl3DfxSetPaletteEXT(GLuint *pal)
{
  fxMesaContext fxMesa =fxMesaCurrentCtx;
  
  if (MESA_VERBOSE&VERBOSE_DRIVER) {
    int i;

    fprintf(stderr,"fxmesa: gl3DfxSetPaletteEXT()\n");

    for(i=0;i<256;i++)
      fprintf(stderr,"%x\n",pal[i]);
  }
  
  if(fxMesa) {
    fxMesa->haveGlobalPaletteTexture=1;
    
    FX_grTexDownloadTable(GR_TMU0,GR_TEXTABLE_PALETTE,(GuTexPalette *)pal);
    if (fxMesa->haveTwoTMUs)
    	 FX_grTexDownloadTable(GR_TMU1,GR_TEXTABLE_PALETTE,(GuTexPalette *)pal);
  }
}


static GrScreenResolution_t fxBestResolution(int width, int height, int aux)
{
  static int resolutions[][5]={ 
    { 512, 384, GR_RESOLUTION_512x384, 2, 2 },
    { 640, 400, GR_RESOLUTION_640x400, 2, 2 },
    { 640, 480, GR_RESOLUTION_640x480, 2, 2 },
    { 800, 600, GR_RESOLUTION_800x600, 4, 2 },
    { 960, 720, GR_RESOLUTION_960x720, 6, 4 }
#ifdef GR_RESOLUTION_1024x768
    ,{ 1024, 768, GR_RESOLUTION_1024x768, 8, 4 }
#endif
#ifdef GR_RESOLUTION_1280x1024
    ,{ 1024, 768, GR_RESOLUTION_1280x1024, 8, 8 }
#endif
#ifdef GR_RESOLUTION_1600x1200
    ,{ 1024, 768, GR_RESOLUTION_1600x1200, 16, 8 }
#endif
  };
  int NUM_RESOLUTIONS = sizeof(resolutions) / (sizeof(int)*5);
  int i,fbmem;
  GrScreenResolution_t lastvalidres=resolutions[1][2];

  fxQueryHardware();

  if(glbHWConfig.SSTs[glbCurrentBoard].type==GR_SSTTYPE_VOODOO) {
    fbmem=glbHWConfig.SSTs[glbCurrentBoard].sstBoard.VoodooConfig.fbRam;

    if(glbHWConfig.SSTs[glbCurrentBoard].sstBoard.VoodooConfig.sliDetect)
      fbmem*=2;
  } else if(glbHWConfig.SSTs[glbCurrentBoard].type==GR_SSTTYPE_SST96)
    fbmem=glbHWConfig.SSTs[glbCurrentBoard].sstBoard.SST96Config.fbRam;
  else
    fbmem=2;

  /* A work around for BZFlag */

  if((width==1) && (height==1)) {
    width=640;
    height=480;
  }

  for(i=0;i<NUM_RESOLUTIONS;i++)
    if(resolutions[i][4-aux]<=fbmem) {
      if((width<=resolutions[i][0]) && (height<=resolutions[i][1]))
        return resolutions[i][2];

      lastvalidres=resolutions[i][2];
    }

  return lastvalidres;
}


fxMesaContext GLAPIENTRY fxMesaCreateBestContext(GLuint win,GLint width, GLint height,
					       const GLint attribList[])
{
  GrScreenRefresh_t refresh;
  int i;
  int res,aux;
  refresh=GR_REFRESH_75Hz;

  if(getenv("SST_SCREENREFRESH")) {
    if(!strcmp(getenv("SST_SCREENREFRESH"),"60"))
      refresh=GR_REFRESH_60Hz;
    if(!strcmp(getenv("SST_SCREENREFRESH"),"70"))
      refresh=GR_REFRESH_70Hz;
    if(!strcmp(getenv("SST_SCREENREFRESH"),"72"))
      refresh=GR_REFRESH_72Hz;
    if(!strcmp(getenv("SST_SCREENREFRESH"),"75"))
      refresh=GR_REFRESH_75Hz;
    if(!strcmp(getenv("SST_SCREENREFRESH"),"80"))
      refresh=GR_REFRESH_80Hz;
    if(!strcmp(getenv("SST_SCREENREFRESH"),"85"))
      refresh=GR_REFRESH_85Hz;
    if(!strcmp(getenv("SST_SCREENREFRESH"),"90"))
      refresh=GR_REFRESH_90Hz;
    if(!strcmp(getenv("SST_SCREENREFRESH"),"100"))
      refresh=GR_REFRESH_100Hz;
    if(!strcmp(getenv("SST_SCREENREFRESH"),"120"))
      refresh=GR_REFRESH_120Hz;
  }

  aux=0;
  for(i=0;attribList[i]!=FXMESA_NONE;i++)
    if((attribList[i]==FXMESA_ALPHA_SIZE) ||
       (attribList[i]==FXMESA_DEPTH_SIZE)) {
      if(attribList[++i]>0) {
        aux=1;
        break;
      }
    }

  res=fxBestResolution(width,height,aux);

  return fxMesaCreateContext(win,res,refresh,attribList);
}


#if 0
void fxsignals()
{
   signal(SIGINT,SIG_IGN);
   signal(SIGHUP,SIG_IGN);
   signal(SIGPIPE,SIG_IGN);
   signal(SIGFPE,SIG_IGN);
   signal(SIGBUS,SIG_IGN);
   signal(SIGILL,SIG_IGN);
   signal(SIGSEGV,SIG_IGN);
   signal(SIGTERM,SIG_IGN);
}
#endif

/*
 * Create a new FX/Mesa context and return a handle to it.
 */
fxMesaContext GLAPIENTRY fxMesaCreateContext(GLuint win,
                                             GrScreenResolution_t res,
                                             GrScreenRefresh_t ref,
                                             const GLint attribList[])
{
   fxMesaContext fxMesa = NULL;
   int i,type;
   int aux;
   GLboolean doubleBuffer=GL_FALSE;
   GLboolean alphaBuffer=GL_FALSE;
   GLboolean verbose=GL_FALSE;
   GLint depthSize=0;
   GLint stencilSize=0;
   GLint accumSize=0;
   GLcontext *shareCtx = NULL;
   GLcontext *ctx = 0;
   /*FX_GrContext_t glideContext = 0;*/
   char *errorstr;

   if (MESA_VERBOSE&VERBOSE_DRIVER) {
      fprintf(stderr,"fxmesa: fxMesaCreateContext() Start\n");
   }

   if(getenv("MESA_FX_INFO"))
      verbose=GL_TRUE;

   aux=0;
   i=0;
   while(attribList[i]!=FXMESA_NONE) {
      switch (attribList[i]) {
      case FXMESA_DOUBLEBUFFER:
	 doubleBuffer=GL_TRUE;
	 break;
      case FXMESA_ALPHA_SIZE:
	 i++;
	 alphaBuffer=attribList[i]>0;
	 if(alphaBuffer)
	    aux=1;
	 break;
      case FXMESA_DEPTH_SIZE:
	 i++;
	 depthSize=attribList[i];
	 if(depthSize) {
	    aux=1;
            depthSize = 16;
         }
	 break;
      case FXMESA_STENCIL_SIZE:
	 i++;
	 stencilSize=attribList[i];
	 break;
      case FXMESA_ACCUM_SIZE:
	 i++;
	 accumSize=attribList[i];
	 break;
	 /* XXX ugly hack here for sharing display lists */
#define FXMESA_SHARE_CONTEXT 990099  /* keep in sync with xmesa1.c! */
      case FXMESA_SHARE_CONTEXT:
	 i++;
	 {
	    const void *vPtr = &attribList[i];
	    GLcontext **ctx = (GLcontext **) vPtr;
	    shareCtx = *ctx;
	 }
	 break;
      default:
	 if (MESA_VERBOSE&VERBOSE_DRIVER) {
	    fprintf(stderr,"fxmesa: fxMesaCreateContext() End (defualt)\n");
	 }
	 return NULL;
      }
      i++;
   }

   /* A workaround for Linux GLQuake */
   if(depthSize && alphaBuffer)
      alphaBuffer=0;

   if(verbose)
      fprintf(stderr,"Mesa fx Voodoo Device Driver v0.30\nWritten by David Bucciarelli (davibu@tin.it.it)\n");

   if((type=fxQueryHardware()) < 0) {
      fprintf(stderr,"fx Driver: ERROR no Voodoo1/2 Graphics or Voodoo Rush !\n");
      return NULL;
   }

   if(type==GR_SSTTYPE_VOODOO)
      win=0;

   grSstSelect(glbCurrentBoard);

   fxMesa=(fxMesaContext)calloc(1,sizeof(struct tfxMesaContext));
   if(!fxMesa) {
      errorstr = "malloc";
      goto errorhandler;
   }

   if(glbHWConfig.SSTs[glbCurrentBoard].type==GR_SSTTYPE_VOODOO)
      fxMesa->haveTwoTMUs=(glbHWConfig.SSTs[glbCurrentBoard].sstBoard.VoodooConfig.nTexelfx > 1);
   else if(glbHWConfig.SSTs[glbCurrentBoard].type==GR_SSTTYPE_SST96)
      fxMesa->haveTwoTMUs=(glbHWConfig.SSTs[glbCurrentBoard].sstBoard.SST96Config.nTexelfx > 1);
   else
      fxMesa->haveTwoTMUs=GL_FALSE;

   fxMesa->haveDoubleBuffer=doubleBuffer;
   fxMesa->haveAlphaBuffer=alphaBuffer;
   fxMesa->haveGlobalPaletteTexture=GL_FALSE;
   fxMesa->haveZBuffer=depthSize ? 1 : 0;
   fxMesa->verbose=verbose;
   fxMesa->board=glbCurrentBoard;


   fxMesa->glideContext = FX_grSstWinOpen((FxU32)win,res,ref,
#if  FXMESA_USE_ARGB
					  GR_COLORFORMAT_ARGB,
#else
					  GR_COLORFORMAT_ABGR,
#endif
					  GR_ORIGIN_LOWER_LEFT,
					  2,aux);
   if (!fxMesa->glideContext){
      errorstr = "grSstWinOpen"; 
      goto errorhandler;
   }

   /* Pixel tables are use during pixel read-back */
#if FXMESA_USE_ARGB 
   fxInitPixelTables(fxMesa, GL_FALSE); /* Force RGB pixel order */	
#else
   if (glbHWConfig.SSTs[glbCurrentBoard].type == GR_SSTTYPE_VOODOO) {
      /* jk991130 - GROSS HACK!!! - Voodoo 3s don't use BGR!!
       * the only way to tell if it's a Voodoo 3 at this stage of the
       * ballgame (no Glide 3.x for linux *yet*) is to query the # of TMUs
       * as Voodoo3s have 2 TMUs on board, Banshee has only 1
       * Thanks to Joseph Kain for that one
       */
      GrVoodooConfig_t *voodoo;
      voodoo = &glbHWConfig.SSTs[glbCurrentBoard].sstBoard.VoodooConfig;

      printf("nTexelfx  %d\n", voodoo->nTexelfx);
      printf("fbRam %d\n", voodoo->fbRam);
      printf("fbiRev %d\n", voodoo->fbiRev);

      if (voodoo->nTexelfx == 2 && voodoo->fbiRev != 260) {
         /* RGB pixel order (Voodoo3, but some Quantum3D models) */
         fxInitPixelTables(fxMesa, GL_FALSE);
      }
      else {
         /* BGR pixel order on Voodoo1/2, or certain Quantum3D models  */
         fxInitPixelTables(fxMesa, GL_TRUE);
      }
   }
   else {
      fxInitPixelTables(fxMesa, GL_FALSE); /* use RGB pixel order otherwise */
   }
#endif

   fxMesa->width=FX_grSstScreenWidth();
   fxMesa->height=FX_grSstScreenHeight();

   fxMesa->clipMinX = 0;
   fxMesa->clipMaxX = fxMesa->width;
   fxMesa->clipMinY = 0;
   fxMesa->clipMaxY = fxMesa->height;

   fxMesa->screen_width = fxMesa->width;
   fxMesa->screen_height = fxMesa->height;
   fxMesa->x_offset = 0;
   fxMesa->y_offset = 0;
   fxMesa->y_delta = 0;
   
   fxMesa->needClip = 0;

   if(verbose)
      fprintf(stderr,"Glide screen size: %dx%d\n",
              (int)FX_grSstScreenWidth(),(int)FX_grSstScreenHeight());

   fxMesa->glVis=gl_create_visual(GL_TRUE,     /* RGB mode */
				  alphaBuffer,
				  doubleBuffer,
				  GL_FALSE,    /* stereo */
				  depthSize,   /* depth_size */
				  stencilSize, /* stencil_size */
				  accumSize,   /* accum_size */
				  0,           /* index bits */
				  5,6,5,0);    /* RGBA bits */
   if (!fxMesa->glVis) {
      errorstr = "gl_create_visual";
      goto errorhandler;
   }

   ctx = fxMesa->glCtx=gl_create_context(fxMesa->glVis,
					 shareCtx,  /* share list context */
					 (void *) fxMesa, GL_TRUE);
   if (!ctx) {
      errorstr = "gl_create_context";
      goto errorhandler;
   }


   if (!fxDDInitFxMesaContext( fxMesa )) {
      errorstr = "fxDDInitFxMesaContext failed"; 
      goto errorhandler;
   }


   fxMesa->glBuffer=gl_create_framebuffer(fxMesa->glVis,
                                          GL_FALSE,  /* no software depth */
                                          fxMesa->glVis->StencilBits > 0,
                                          fxMesa->glVis->AccumBits > 0,
                                          fxMesa->glVis->AlphaBits > 0 );
   if (!fxMesa->glBuffer) {
      errorstr = "gl_create_framebuffer";
      goto errorhandler;
   }
  
   glbTotNumCtx++;

   /* install signal handlers */
#if defined(__linux__)
   /* Only install if environment var. is not set. */
   if (fxMesa->glCtx->CatchSignals && !getenv("MESA_FX_NO_SIGNALS")) {
      signal(SIGINT,cleangraphics_handler);
      signal(SIGHUP,cleangraphics_handler);
      signal(SIGPIPE,cleangraphics_handler);
      signal(SIGFPE,cleangraphics_handler);
      signal(SIGBUS,cleangraphics_handler);
      signal(SIGILL,cleangraphics_handler);
      signal(SIGSEGV,cleangraphics_handler);
      signal(SIGTERM,cleangraphics_handler);
   }
#endif

   if (MESA_VERBOSE&VERBOSE_DRIVER) {
      fprintf(stderr,"fxmesa: fxMesaCreateContext() End\n");
   }

   return fxMesa;

 errorhandler:
   if (fxMesa) {
      if (fxMesa->glideContext)
	 FX_grSstWinClose(fxMesa->glideContext);
      fxMesa->glideContext = 0;
      
      if (fxMesa->state)  
	 free(fxMesa->state);
      if (fxMesa->fogTable)
	 free(fxMesa->fogTable);
      if (fxMesa->glBuffer)
	 gl_destroy_framebuffer(fxMesa->glBuffer);
      if (fxMesa->glVis)
	 gl_destroy_visual(fxMesa->glVis);
      if (fxMesa->glCtx)
	 gl_destroy_context(fxMesa->glCtx);
      free(fxMesa);
   }
   
   if (MESA_VERBOSE&VERBOSE_DRIVER) {
      fprintf(stderr,"fxmesa: fxMesaCreateContext() End (%s)\n",errorstr);
   }
   return NULL;
}


/*
 * Function to set the new window size in the context (mainly for the Voodoo Rush)
 */
void GLAPIENTRY fxMesaUpdateScreenSize(fxMesaContext fxMesa)
{
  fxMesa->width=FX_grSstScreenWidth();
  fxMesa->height=FX_grSstScreenHeight();
}


/*
 * Destroy the given FX/Mesa context.
 */
void GLAPIENTRY fxMesaDestroyContext(fxMesaContext fxMesa)
{
  if (MESA_VERBOSE&VERBOSE_DRIVER) {
    fprintf(stderr,"fxmesa: fxMesaDestroyContext()\n");
  }

  if(fxMesa) {
    gl_destroy_visual(fxMesa->glVis);
    gl_destroy_context(fxMesa->glCtx);
    gl_destroy_framebuffer(fxMesa->glBuffer);

    glbTotNumCtx--;

    fxCloseHardware();
    FX_grSstWinClose(fxMesa->glideContext);

    if(fxMesa->verbose) {
      fprintf(stderr,"Misc Stats:\n");
      fprintf(stderr,"  # swap buffer: %u\n",fxMesa->stats.swapBuffer);

      if(!fxMesa->stats.swapBuffer)
        fxMesa->stats.swapBuffer=1;

      fprintf(stderr,"Textures Stats:\n");
      fprintf(stderr,"  Free texture memory on TMU0: %d:\n",fxMesa->freeTexMem[FX_TMU0]);
      if(fxMesa->haveTwoTMUs)
        fprintf(stderr,"  Free texture memory on TMU1: %d:\n",fxMesa->freeTexMem[FX_TMU1]);
      fprintf(stderr,"  # request to TMM to upload a texture objects: %u\n",
              fxMesa->stats.reqTexUpload);
      fprintf(stderr,"  # request to TMM to upload a texture objects per swapbuffer: %.2f\n",
              fxMesa->stats.reqTexUpload/(float)fxMesa->stats.swapBuffer);
      fprintf(stderr,"  # texture objects uploaded: %u\n",
              fxMesa->stats.texUpload);
      fprintf(stderr,"  # texture objects uploaded per swapbuffer: %.2f\n",
              fxMesa->stats.texUpload/(float)fxMesa->stats.swapBuffer);
      fprintf(stderr,"  # MBs uploaded to texture memory: %.2f\n",
              fxMesa->stats.memTexUpload/(float)(1<<20));
      fprintf(stderr,"  # MBs uploaded to texture memory per swapbuffer: %.2f\n",
              (fxMesa->stats.memTexUpload/(float)fxMesa->stats.swapBuffer)/(float)(1<<20));
    }
    if (fxMesa->state)  
       free(fxMesa->state);
    if (fxMesa->fogTable)
       free(fxMesa->fogTable);
    fxTMClose(fxMesa);
    
    free(fxMesa);
  }

  if(fxMesa==fxMesaCurrentCtx)
    fxMesaCurrentCtx=NULL;
}


/*
 * Make the specified FX/Mesa context the current one.
 */
void GLAPIENTRY fxMesaMakeCurrent(fxMesaContext fxMesa)
{
  if (MESA_VERBOSE&VERBOSE_DRIVER) {
    fprintf(stderr,"fxmesa: fxMesaMakeCurrent(...) Start\n");
  }

  if(!fxMesa) {
    gl_make_current(NULL,NULL);
    fxMesaCurrentCtx=NULL;

    if (MESA_VERBOSE&VERBOSE_DRIVER) {
      fprintf(stderr,"fxmesa: fxMesaMakeCurrent(NULL) End\n");
    }

    return;
  }

  /* if this context is already the current one, we can return early */
  if (fxMesaCurrentCtx == fxMesa
      && fxMesaCurrentCtx->glCtx == gl_get_current_context()) {
     if (MESA_VERBOSE&VERBOSE_DRIVER) {
        fprintf(stderr,"fxmesa: fxMesaMakeCurrent(fxMesaCurrentCtx==fxMesa) End\n");
    }

    return;
  }

  if(fxMesaCurrentCtx)
    grGlideGetState((GrState*)fxMesaCurrentCtx->state);

  fxMesaCurrentCtx=fxMesa;

  grSstSelect(fxMesa->board);
  grGlideSetState((GrState*)fxMesa->state);

  gl_make_current(fxMesa->glCtx,fxMesa->glBuffer);

  fxSetupDDPointers(fxMesa->glCtx);

  /* The first time we call MakeCurrent we set the initial viewport size */
  if(fxMesa->glCtx->Viewport.Width==0)
    gl_Viewport(fxMesa->glCtx,0,0,fxMesa->width,fxMesa->height);

  if (MESA_VERBOSE&VERBOSE_DRIVER) {
    fprintf(stderr,"fxmesa: fxMesaMakeCurrent(...) End\n");
  }
}


/*
 * Swap front/back buffers for current context if double buffered.
 */
void GLAPIENTRY fxMesaSwapBuffers(void)
{
  if (MESA_VERBOSE&VERBOSE_DRIVER) {
    fprintf(stderr,"fxmesa: ------------------------------- fxMesaSwapBuffers() -------------------------------\n");
  }

  if(fxMesaCurrentCtx) {
   FLUSH_VB( fxMesaCurrentCtx->glCtx, "swap buffers" );

    if(fxMesaCurrentCtx->haveDoubleBuffer) {

      grBufferSwap(fxMesaCurrentCtx->swapInterval);

      /*
       * Don't allow swap buffer commands to build up!
       */
      while(FX_grGetInteger(FX_PENDING_BUFFERSWAPS)>fxMesaCurrentCtx->maxPendingSwapBuffers)
        /* The driver is able to sleep when waiting for the completation
           of multiple swapbuffer operations instead of wasting
           CPU time (NOTE: you must uncomment the following line in the
           in order to enable this option) */
        /* usleep(10000); */
        ;

      fxMesaCurrentCtx->stats.swapBuffer++;
    }
  }
}


/*
 * Query 3Dfx hardware presence/kind
 */
int GLAPIENTRY fxQueryHardware(void)
{
  if (MESA_VERBOSE&VERBOSE_DRIVER) {
    fprintf(stderr,"fxmesa: fxQueryHardware() Start\n");
  }

  if(!glbGlideInitialized) {
    grGlideInit();
    if(FX_grSstQueryHardware(&glbHWConfig)) {
      grSstSelect(glbCurrentBoard);
      glb3DfxPresent=1;

      if(getenv("MESA_FX_INFO")) {
        char buf[80];
                        
        FX_grGlideGetVersion(buf);
        fprintf(stderr,"Using Glide V%s\n","");
        fprintf(stderr,"Number of boards: %d\n",glbHWConfig.num_sst);

        if(glbHWConfig.SSTs[glbCurrentBoard].type==GR_SSTTYPE_VOODOO) {
          fprintf(stderr,"Framebuffer RAM: %d\n",
                  glbHWConfig.SSTs[glbCurrentBoard].sstBoard.VoodooConfig.sliDetect ?
                  (glbHWConfig.SSTs[glbCurrentBoard].sstBoard.VoodooConfig.fbRam*2) :
                  glbHWConfig.SSTs[glbCurrentBoard].sstBoard.VoodooConfig.fbRam);
          fprintf(stderr,"Number of TMUs: %d\n",
                  glbHWConfig.SSTs[glbCurrentBoard].sstBoard.VoodooConfig.nTexelfx);
          fprintf(stderr,"SLI detected: %d\n",
                  glbHWConfig.SSTs[glbCurrentBoard].sstBoard.VoodooConfig.sliDetect);
        } else if(glbHWConfig.SSTs[glbCurrentBoard].type==GR_SSTTYPE_SST96) {
          fprintf(stderr,"Framebuffer RAM: %d\n",
                  glbHWConfig.SSTs[glbCurrentBoard].sstBoard.SST96Config.fbRam);
          fprintf(stderr,"Number of TMUs: %d\n",
                  glbHWConfig.SSTs[glbCurrentBoard].sstBoard.SST96Config.nTexelfx);
        }

      }
    } else
      glb3DfxPresent=0;

    glbGlideInitialized=1;

#if defined(__WIN32__)
    onexit((_onexit_t)cleangraphics);
#elif defined(__linux__)
    /* Only register handler if environment variable is not defined. */
    if (!getenv("MESA_FX_NO_SIGNALS")) {
	atexit(cleangraphics);
    }
#endif
  }

  if(!glb3DfxPresent) {
    if (MESA_VERBOSE&VERBOSE_DRIVER) {
      fprintf(stderr,"fxmesa: fxQueryHardware() End (-1)\n");
    }
    return(-1);
  }

  if (MESA_VERBOSE&VERBOSE_DRIVER) {
    fprintf(stderr,"fxmesa: fxQueryHardware() End (voodooo)\n");
  }
  return(glbHWConfig.SSTs[glbCurrentBoard].type);
}


/*
 * Shutdown Glide library
 */
void GLAPIENTRY fxCloseHardware(void)
{
  if(glbGlideInitialized) {
    if(getenv("MESA_FX_INFO")) {
      GrSstPerfStats_t          st;

      FX_grSstPerfStats(&st);
      fprintf(stderr,"Pixels Stats:\n");
      fprintf(stderr,"  # pixels processed (minus buffer clears): %u\n",(unsigned)st.pixelsIn);
      fprintf(stderr,"  # pixels not drawn due to chroma key test failure: %u\n",(unsigned)st.chromaFail);
      fprintf(stderr,"  # pixels not drawn due to depth test failure: %u\n",(unsigned)st.zFuncFail);
      fprintf(stderr,"  # pixels not drawn due to alpha test failure: %u\n",(unsigned)st.aFuncFail);
      fprintf(stderr,"  # pixels drawn (including buffer clears and LFB writes): %u\n",(unsigned)st.pixelsOut);
    }

    if(glbTotNumCtx==0) {
      grGlideShutdown();
      glbGlideInitialized=0;
    }
  }
}


#else


/*
 * Need this to provide at least one external definition.
 */

int gl_fx_dummy_function_api(void)
{
  return 0;
}

#endif  /* FX */