summaryrefslogtreecommitdiffstats
path: root/src/mesa/state_tracker/st_extensions.c
blob: f9b7a445f1fdabb7cf91426f7952e43b61f94065 (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
/**************************************************************************
 * 
 * Copyright 2007 VMware, Inc.
 * Copyright (c) 2008 VMware, Inc.
 * 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, sub license, 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 (including the
 * next paragraph) 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 NON-INFRINGEMENT.
 * IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS 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 "main/imports.h"
#include "main/context.h"
#include "main/macros.h"
#include "main/version.h"

#include "pipe/p_context.h"
#include "pipe/p_defines.h"
#include "pipe/p_screen.h"

#include "st_context.h"
#include "st_extensions.h"
#include "st_format.h"

static unsigned _min(unsigned a, unsigned b)
{
   return (a < b) ? a : b;
}

static float _maxf(float a, float b)
{
   return (a > b) ? a : b;
}

static int _clamp(int a, int min, int max)
{
   if (a < min)
      return min;
   else if (a > max)
      return max;
   else
      return a;
}


/**
 * Query driver to get implementation limits.
 * Note that we have to limit/clamp against Mesa's internal limits too.
 */
void st_init_limits(struct st_context *st)
{
   struct pipe_screen *screen = st->pipe->screen;
   struct gl_constants *c = &st->ctx->Const;
   unsigned sh;
   boolean can_ubo = TRUE;

   c->MaxTextureLevels
      = _min(screen->get_param(screen, PIPE_CAP_MAX_TEXTURE_2D_LEVELS),
            MAX_TEXTURE_LEVELS);

   c->Max3DTextureLevels
      = _min(screen->get_param(screen, PIPE_CAP_MAX_TEXTURE_3D_LEVELS),
            MAX_3D_TEXTURE_LEVELS);

   c->MaxCubeTextureLevels
      = _min(screen->get_param(screen, PIPE_CAP_MAX_TEXTURE_CUBE_LEVELS),
            MAX_CUBE_TEXTURE_LEVELS);

   c->MaxTextureRectSize
      = _min(1 << (c->MaxTextureLevels - 1), MAX_TEXTURE_RECT_SIZE);

   c->MaxArrayTextureLayers
      = screen->get_param(screen, PIPE_CAP_MAX_TEXTURE_ARRAY_LAYERS);

   /* Define max viewport size and max renderbuffer size in terms of
    * max texture size (note: max tex RECT size = max tex 2D size).
    * If this isn't true for some hardware we'll need new PIPE_CAP_ queries.
    */
   c->MaxViewportWidth =
   c->MaxViewportHeight =
   c->MaxRenderbufferSize = c->MaxTextureRectSize;

   c->MaxDrawBuffers = c->MaxColorAttachments =
      _clamp(screen->get_param(screen, PIPE_CAP_MAX_RENDER_TARGETS),
             1, MAX_DRAW_BUFFERS);

   c->MaxDualSourceDrawBuffers
      = _clamp(screen->get_param(screen, PIPE_CAP_MAX_DUAL_SOURCE_RENDER_TARGETS),
              0, MAX_DRAW_BUFFERS);

   c->MaxLineWidth
      = _maxf(1.0f, screen->get_paramf(screen,
                                       PIPE_CAPF_MAX_LINE_WIDTH));
   c->MaxLineWidthAA
      = _maxf(1.0f, screen->get_paramf(screen,
                                       PIPE_CAPF_MAX_LINE_WIDTH_AA));

   c->MaxPointSize
      = _maxf(1.0f, screen->get_paramf(screen,
                                       PIPE_CAPF_MAX_POINT_WIDTH));
   c->MaxPointSizeAA
      = _maxf(1.0f, screen->get_paramf(screen,
                                       PIPE_CAPF_MAX_POINT_WIDTH_AA));
   /* called after _mesa_create_context/_mesa_init_point, fix default user
    * settable max point size up
    */
   st->ctx->Point.MaxSize = MAX2(c->MaxPointSize, c->MaxPointSizeAA);
   /* these are not queryable. Note that GL basically mandates a 1.0 minimum
    * for non-aa sizes, but we can go down to 0.0 for aa points.
    */
   c->MinPointSize = 1.0f;
   c->MinPointSizeAA = 0.0f;

   c->MaxTextureMaxAnisotropy
      = _maxf(2.0f, screen->get_paramf(screen,
                                 PIPE_CAPF_MAX_TEXTURE_ANISOTROPY));

   c->MaxTextureLodBias
      = screen->get_paramf(screen, PIPE_CAPF_MAX_TEXTURE_LOD_BIAS);

   c->QuadsFollowProvokingVertexConvention = screen->get_param(
      screen, PIPE_CAP_QUADS_FOLLOW_PROVOKING_VERTEX_CONVENTION);

   c->MaxUniformBlockSize =
      screen->get_shader_param(screen, PIPE_SHADER_FRAGMENT,
                               PIPE_SHADER_CAP_MAX_CONSTS) * 16;
   if (c->MaxUniformBlockSize < 16384) {
      can_ubo = FALSE;
   }

   for (sh = 0; sh < PIPE_SHADER_TYPES; ++sh) {
      struct gl_shader_compiler_options *options;
      struct gl_program_constants *pc;

      switch (sh) {
      case PIPE_SHADER_FRAGMENT:
         pc = &c->Program[MESA_SHADER_FRAGMENT];
         options = &st->ctx->ShaderCompilerOptions[MESA_SHADER_FRAGMENT];
         break;
      case PIPE_SHADER_VERTEX:
         pc = &c->Program[MESA_SHADER_VERTEX];
         options = &st->ctx->ShaderCompilerOptions[MESA_SHADER_VERTEX];
         break;
      case PIPE_SHADER_GEOMETRY:
         pc = &c->Program[MESA_SHADER_GEOMETRY];
         options = &st->ctx->ShaderCompilerOptions[MESA_SHADER_GEOMETRY];
         break;
      default:
         /* compute shader, etc. */
         continue;
      }

      pc->MaxTextureImageUnits =
         _min(screen->get_shader_param(screen, sh,
                                       PIPE_SHADER_CAP_MAX_TEXTURE_SAMPLERS),
              MAX_TEXTURE_IMAGE_UNITS);

      pc->MaxInstructions    = pc->MaxNativeInstructions    =
         screen->get_shader_param(screen, sh, PIPE_SHADER_CAP_MAX_INSTRUCTIONS);
      pc->MaxAluInstructions = pc->MaxNativeAluInstructions =
         screen->get_shader_param(screen, sh, PIPE_SHADER_CAP_MAX_ALU_INSTRUCTIONS);
      pc->MaxTexInstructions = pc->MaxNativeTexInstructions =
         screen->get_shader_param(screen, sh, PIPE_SHADER_CAP_MAX_TEX_INSTRUCTIONS);
      pc->MaxTexIndirections = pc->MaxNativeTexIndirections =
         screen->get_shader_param(screen, sh, PIPE_SHADER_CAP_MAX_TEX_INDIRECTIONS);
      pc->MaxAttribs         = pc->MaxNativeAttribs         =
         screen->get_shader_param(screen, sh, PIPE_SHADER_CAP_MAX_INPUTS);
      pc->MaxTemps           = pc->MaxNativeTemps           =
         screen->get_shader_param(screen, sh, PIPE_SHADER_CAP_MAX_TEMPS);
      pc->MaxAddressRegs     = pc->MaxNativeAddressRegs     =
         _min(screen->get_shader_param(screen, sh, PIPE_SHADER_CAP_MAX_ADDRS),
              MAX_PROGRAM_ADDRESS_REGS);
      pc->MaxParameters      = pc->MaxNativeParameters      =
         screen->get_shader_param(screen, sh, PIPE_SHADER_CAP_MAX_CONSTS);

      pc->MaxUniformComponents = 4 * MIN2(pc->MaxNativeParameters, MAX_UNIFORMS);

      pc->MaxUniformBlocks =
         screen->get_shader_param(screen, sh, PIPE_SHADER_CAP_MAX_CONST_BUFFERS);
      if (pc->MaxUniformBlocks)
         pc->MaxUniformBlocks -= 1; /* The first one is for ordinary uniforms. */
      pc->MaxUniformBlocks = _min(pc->MaxUniformBlocks, MAX_UNIFORM_BUFFERS);

      pc->MaxCombinedUniformComponents = (pc->MaxUniformComponents +
                                          c->MaxUniformBlockSize / 4 *
                                          pc->MaxUniformBlocks);

      /* Gallium doesn't really care about local vs. env parameters so use the
       * same limits.
       */
      pc->MaxLocalParams = MIN2(pc->MaxParameters, MAX_PROGRAM_LOCAL_PARAMS);
      pc->MaxEnvParams = MIN2(pc->MaxParameters, MAX_PROGRAM_ENV_PARAMS);

      options->EmitNoNoise = TRUE;

      /* TODO: make these more fine-grained if anyone needs it */
      options->MaxIfDepth = screen->get_shader_param(screen, sh, PIPE_SHADER_CAP_MAX_CONTROL_FLOW_DEPTH);
      options->EmitNoLoops = !screen->get_shader_param(screen, sh, PIPE_SHADER_CAP_MAX_CONTROL_FLOW_DEPTH);
      options->EmitNoFunctions = !screen->get_shader_param(screen, sh, PIPE_SHADER_CAP_SUBROUTINES);
      options->EmitNoMainReturn = !screen->get_shader_param(screen, sh, PIPE_SHADER_CAP_SUBROUTINES);

      options->EmitNoCont = !screen->get_shader_param(screen, sh, PIPE_SHADER_CAP_TGSI_CONT_SUPPORTED);

      options->EmitNoIndirectInput = !screen->get_shader_param(screen, sh,
                                        PIPE_SHADER_CAP_INDIRECT_INPUT_ADDR);
      options->EmitNoIndirectOutput = !screen->get_shader_param(screen, sh,
                                        PIPE_SHADER_CAP_INDIRECT_OUTPUT_ADDR);
      options->EmitNoIndirectTemp = !screen->get_shader_param(screen, sh,
                                        PIPE_SHADER_CAP_INDIRECT_TEMP_ADDR);
      options->EmitNoIndirectUniform = !screen->get_shader_param(screen, sh,
                                        PIPE_SHADER_CAP_INDIRECT_CONST_ADDR);

      if (pc->MaxNativeInstructions &&
          (options->EmitNoIndirectUniform || pc->MaxUniformBlocks < 12)) {
         can_ubo = FALSE;
      }

      if (options->EmitNoLoops)
         options->MaxUnrollIterations = MIN2(screen->get_shader_param(screen, sh, PIPE_SHADER_CAP_MAX_INSTRUCTIONS), 65536);
      else
         options->MaxUnrollIterations = 255; /* SM3 limit */
      options->LowerClipDistance = true;
   }

   c->MaxCombinedTextureImageUnits =
         _min(c->Program[MESA_SHADER_VERTEX].MaxTextureImageUnits +
              c->Program[MESA_SHADER_GEOMETRY].MaxTextureImageUnits +
              c->Program[MESA_SHADER_FRAGMENT].MaxTextureImageUnits,
              MAX_COMBINED_TEXTURE_IMAGE_UNITS);

   /* This depends on program constants. */
   c->MaxTextureCoordUnits
      = _min(c->Program[MESA_SHADER_FRAGMENT].MaxTextureImageUnits, MAX_TEXTURE_COORD_UNITS);

   c->MaxTextureUnits = _min(c->Program[MESA_SHADER_FRAGMENT].MaxTextureImageUnits, c->MaxTextureCoordUnits);

   c->Program[MESA_SHADER_VERTEX].MaxAttribs = MIN2(c->Program[MESA_SHADER_VERTEX].MaxAttribs, 16);

   /* PIPE_SHADER_CAP_MAX_INPUTS for the FS specifies the maximum number
    * of inputs. It's always 2 colors + N generic inputs. */
   c->MaxVarying = screen->get_shader_param(screen, PIPE_SHADER_FRAGMENT,
                                            PIPE_SHADER_CAP_MAX_INPUTS);
   c->MaxVarying = MIN2(c->MaxVarying, MAX_VARYING);
   c->Program[MESA_SHADER_FRAGMENT].MaxInputComponents = c->MaxVarying * 4;
   c->Program[MESA_SHADER_VERTEX].MaxOutputComponents = c->MaxVarying * 4;
   c->Program[MESA_SHADER_GEOMETRY].MaxInputComponents = c->MaxVarying * 4;
   c->Program[MESA_SHADER_GEOMETRY].MaxOutputComponents = c->MaxVarying * 4;
   c->MaxGeometryOutputVertices = screen->get_param(screen, PIPE_CAP_MAX_GEOMETRY_OUTPUT_VERTICES);
   c->MaxGeometryTotalOutputComponents = screen->get_param(screen, PIPE_CAP_MAX_GEOMETRY_TOTAL_OUTPUT_COMPONENTS);

   c->MinProgramTexelOffset = screen->get_param(screen, PIPE_CAP_MIN_TEXEL_OFFSET);
   c->MaxProgramTexelOffset = screen->get_param(screen, PIPE_CAP_MAX_TEXEL_OFFSET);

   c->UniformBooleanTrue = ~0;

   c->MaxTransformFeedbackBuffers =
      screen->get_param(screen, PIPE_CAP_MAX_STREAM_OUTPUT_BUFFERS);
   c->MaxTransformFeedbackBuffers = MIN2(c->MaxTransformFeedbackBuffers, MAX_FEEDBACK_BUFFERS);
   c->MaxTransformFeedbackSeparateComponents =
      screen->get_param(screen, PIPE_CAP_MAX_STREAM_OUTPUT_SEPARATE_COMPONENTS);
   c->MaxTransformFeedbackInterleavedComponents =
      screen->get_param(screen, PIPE_CAP_MAX_STREAM_OUTPUT_INTERLEAVED_COMPONENTS);

   c->StripTextureBorder = GL_TRUE;

   c->GLSLSkipStrictMaxUniformLimitCheck =
      screen->get_param(screen, PIPE_CAP_TGSI_CAN_COMPACT_CONSTANTS);

   if (can_ubo) {
      st->ctx->Extensions.ARB_uniform_buffer_object = GL_TRUE;
      c->UniformBufferOffsetAlignment =
         screen->get_param(screen, PIPE_CAP_CONSTANT_BUFFER_OFFSET_ALIGNMENT);
      c->MaxCombinedUniformBlocks = c->MaxUniformBufferBindings =
         c->Program[MESA_SHADER_VERTEX].MaxUniformBlocks +
         c->Program[MESA_SHADER_GEOMETRY].MaxUniformBlocks +
         c->Program[MESA_SHADER_FRAGMENT].MaxUniformBlocks;
      assert(c->MaxCombinedUniformBlocks <= MAX_COMBINED_UNIFORM_BUFFERS);
   }
}


/**
 * Given a member \c x of struct gl_extensions, return offset of
 * \c x in bytes.
 */
#define o(x) offsetof(struct gl_extensions, x)


struct st_extension_cap_mapping {
   int extension_offset;
   int cap;
};

struct st_extension_format_mapping {
   int extension_offset[2];
   enum pipe_format format[8];

   /* If TRUE, at least one format must be supported for the extensions to be
    * advertised. If FALSE, all the formats must be supported. */
   GLboolean need_at_least_one;
};

/**
 * Enable extensions if certain pipe formats are supported by the driver.
 * What extensions will be enabled and what formats must be supported is
 * described by the array of st_extension_format_mapping.
 *
 * target and bind_flags are passed to is_format_supported.
 */
static void init_format_extensions(struct st_context *st,
                           const struct st_extension_format_mapping *mapping,
                           unsigned num_mappings,
                           enum pipe_texture_target target,
                           unsigned bind_flags)
{
   struct pipe_screen *screen = st->pipe->screen;
   GLboolean *extensions = (GLboolean *) &st->ctx->Extensions;
   unsigned i;
   int j;
   int num_formats = Elements(mapping->format);
   int num_ext = Elements(mapping->extension_offset);

   for (i = 0; i < num_mappings; i++) {
      int num_supported = 0;

      /* Examine each format in the list. */
      for (j = 0; j < num_formats && mapping[i].format[j]; j++) {
         if (screen->is_format_supported(screen, mapping[i].format[j],
                                         target, 0, bind_flags)) {
            num_supported++;
         }
      }

      if (!num_supported ||
          (!mapping[i].need_at_least_one && num_supported != j)) {
         continue;
      }

      /* Enable all extensions in the list. */
      for (j = 0; j < num_ext && mapping[i].extension_offset[j]; j++)
         extensions[mapping[i].extension_offset[j]] = GL_TRUE;
   }
}

/**
 * Use pipe_screen::get_param() to query PIPE_CAP_ values to determine
 * which GL extensions are supported.
 * Quite a few extensions are always supported because they are standard
 * features or can be built on top of other gallium features.
 * Some fine tuning may still be needed.
 */
void st_init_extensions(struct st_context *st)
{
   struct pipe_screen *screen = st->pipe->screen;
   struct gl_context *ctx = st->ctx;
   int i, glsl_feature_level;
   GLboolean *extensions = (GLboolean *) &ctx->Extensions;

   static const struct st_extension_cap_mapping cap_mapping[] = {
      { o(ARB_base_instance),                PIPE_CAP_START_INSTANCE                   },
      { o(ARB_depth_clamp),                  PIPE_CAP_DEPTH_CLIP_DISABLE               },
      { o(ARB_depth_texture),                PIPE_CAP_TEXTURE_SHADOW_MAP               },
      { o(ARB_draw_buffers_blend),           PIPE_CAP_INDEP_BLEND_FUNC                 },
      { o(ARB_draw_instanced),               PIPE_CAP_TGSI_INSTANCEID                  },
      { o(ARB_fragment_program_shadow),      PIPE_CAP_TEXTURE_SHADOW_MAP               },
      { o(ARB_instanced_arrays),             PIPE_CAP_VERTEX_ELEMENT_INSTANCE_DIVISOR  },
      { o(ARB_occlusion_query),              PIPE_CAP_OCCLUSION_QUERY                  },
      { o(ARB_occlusion_query2),             PIPE_CAP_OCCLUSION_QUERY                  },
      { o(ARB_point_sprite),                 PIPE_CAP_POINT_SPRITE                     },
      { o(ARB_seamless_cube_map),            PIPE_CAP_SEAMLESS_CUBE_MAP                },
      { o(ARB_shader_stencil_export),        PIPE_CAP_SHADER_STENCIL_EXPORT            },
      { o(ARB_shader_texture_lod),           PIPE_CAP_SM3                              },
      { o(ARB_shadow),                       PIPE_CAP_TEXTURE_SHADOW_MAP               },
      { o(ARB_texture_mirror_clamp_to_edge), PIPE_CAP_TEXTURE_MIRROR_CLAMP             },
      { o(ARB_texture_non_power_of_two),     PIPE_CAP_NPOT_TEXTURES                    },
      { o(ARB_timer_query),                  PIPE_CAP_QUERY_TIMESTAMP                  },
      { o(ARB_transform_feedback2),          PIPE_CAP_STREAM_OUTPUT_PAUSE_RESUME       },
      { o(ARB_transform_feedback3),          PIPE_CAP_STREAM_OUTPUT_PAUSE_RESUME       },

      { o(EXT_blend_equation_separate),      PIPE_CAP_BLEND_EQUATION_SEPARATE          },
      { o(EXT_draw_buffers2),                PIPE_CAP_INDEP_BLEND_ENABLE               },
      { o(EXT_stencil_two_side),             PIPE_CAP_TWO_SIDED_STENCIL                },
      { o(EXT_texture_array),                PIPE_CAP_MAX_TEXTURE_ARRAY_LAYERS         },
      { o(EXT_texture_filter_anisotropic),   PIPE_CAP_ANISOTROPIC_FILTER               },
      { o(EXT_texture_mirror_clamp),         PIPE_CAP_TEXTURE_MIRROR_CLAMP             },
      { o(EXT_texture_swizzle),              PIPE_CAP_TEXTURE_SWIZZLE                  },
      { o(EXT_transform_feedback),           PIPE_CAP_MAX_STREAM_OUTPUT_BUFFERS        },

      { o(AMD_seamless_cubemap_per_texture), PIPE_CAP_SEAMLESS_CUBE_MAP_PER_TEXTURE    },
      { o(ATI_separate_stencil),             PIPE_CAP_TWO_SIDED_STENCIL                },
      { o(ATI_texture_mirror_once),          PIPE_CAP_TEXTURE_MIRROR_CLAMP             },
      { o(NV_conditional_render),            PIPE_CAP_CONDITIONAL_RENDER               },
      { o(NV_texture_barrier),               PIPE_CAP_TEXTURE_BARRIER                  },
      /* GL_NV_point_sprite is not supported by gallium because we don't
       * support the GL_POINT_SPRITE_R_MODE_NV option. */

      { o(OES_standard_derivatives),         PIPE_CAP_SM3                              },
      { o(ARB_texture_cube_map_array),       PIPE_CAP_CUBE_MAP_ARRAY                   },
      { o(ARB_texture_multisample),          PIPE_CAP_TEXTURE_MULTISAMPLE              }
   };

   /* Required: render target and sampler support */
   static const struct st_extension_format_mapping rendertarget_mapping[] = {
      { { o(ARB_texture_float) },
        { PIPE_FORMAT_R32G32B32A32_FLOAT,
          PIPE_FORMAT_R16G16B16A16_FLOAT } },

      { { o(ARB_texture_rgb10_a2ui) },
        { PIPE_FORMAT_R10G10B10A2_UINT,
          PIPE_FORMAT_B10G10R10A2_UINT },
         GL_TRUE }, /* at least one format must be supported */

      { { o(EXT_framebuffer_sRGB) },
        { PIPE_FORMAT_A8B8G8R8_SRGB,
          PIPE_FORMAT_B8G8R8A8_SRGB },
         GL_TRUE }, /* at least one format must be supported */

      { { o(EXT_packed_float) },
        { PIPE_FORMAT_R11G11B10_FLOAT } },

      { { o(EXT_texture_integer) },
        { PIPE_FORMAT_R32G32B32A32_UINT,
          PIPE_FORMAT_R32G32B32A32_SINT } },

      { { o(ARB_texture_rg) },
        { PIPE_FORMAT_R8_UNORM,
          PIPE_FORMAT_R8G8_UNORM } },
   };

   /* Required: depth stencil and sampler support */
   static const struct st_extension_format_mapping depthstencil_mapping[] = {
      { { o(ARB_depth_buffer_float) },
        { PIPE_FORMAT_Z32_FLOAT,
          PIPE_FORMAT_Z32_FLOAT_S8X24_UINT } },
   };

   /* Required: sampler support */
   static const struct st_extension_format_mapping texture_mapping[] = {
      { { o(ARB_texture_compression_rgtc) },
        { PIPE_FORMAT_RGTC1_UNORM,
          PIPE_FORMAT_RGTC1_SNORM,
          PIPE_FORMAT_RGTC2_UNORM,
          PIPE_FORMAT_RGTC2_SNORM } },

      { { o(EXT_texture_compression_latc) },
        { PIPE_FORMAT_LATC1_UNORM,
          PIPE_FORMAT_LATC1_SNORM,
          PIPE_FORMAT_LATC2_UNORM,
          PIPE_FORMAT_LATC2_SNORM } },

      { { o(EXT_texture_compression_s3tc),
          o(ANGLE_texture_compression_dxt) },
        { PIPE_FORMAT_DXT1_RGB,
          PIPE_FORMAT_DXT1_RGBA,
          PIPE_FORMAT_DXT3_RGBA,
          PIPE_FORMAT_DXT5_RGBA } },

      { { o(EXT_texture_shared_exponent) },
        { PIPE_FORMAT_R9G9B9E5_FLOAT } },

      { { o(EXT_texture_snorm) },
        { PIPE_FORMAT_R8G8B8A8_SNORM } },

      { { o(EXT_texture_sRGB),
          o(EXT_texture_sRGB_decode) },
        { PIPE_FORMAT_A8B8G8R8_SRGB,
          PIPE_FORMAT_B8G8R8A8_SRGB },
        GL_TRUE }, /* at least one format must be supported */

      { { o(ATI_texture_compression_3dc) },
        { PIPE_FORMAT_LATC2_UNORM } },

      { { o(MESA_ycbcr_texture) },
        { PIPE_FORMAT_UYVY,
          PIPE_FORMAT_YUYV },
        GL_TRUE }, /* at least one format must be supported */

      { { o(OES_compressed_ETC1_RGB8_texture) },
        { PIPE_FORMAT_ETC1_RGB8 } },
   };

   /* Required: vertex fetch support. */
   static const struct st_extension_format_mapping vertex_mapping[] = {
      { { o(ARB_vertex_type_2_10_10_10_rev) },
        { PIPE_FORMAT_R10G10B10A2_UNORM,
          PIPE_FORMAT_B10G10R10A2_UNORM,
          PIPE_FORMAT_R10G10B10A2_SNORM,
          PIPE_FORMAT_B10G10R10A2_SNORM,
          PIPE_FORMAT_R10G10B10A2_USCALED,
          PIPE_FORMAT_B10G10R10A2_USCALED,
          PIPE_FORMAT_R10G10B10A2_SSCALED,
          PIPE_FORMAT_B10G10R10A2_SSCALED } },
      { { o(ARB_vertex_type_10f_11f_11f_rev) },
        { PIPE_FORMAT_R11G11B10_FLOAT } },
   };

   static const struct st_extension_format_mapping tbo_rgb32[] = {
      { {o(ARB_texture_buffer_object_rgb32) },
        { PIPE_FORMAT_R32G32B32_FLOAT,
          PIPE_FORMAT_R32G32B32_UINT,
          PIPE_FORMAT_R32G32B32_SINT,
        } },
   };

   /*
    * Extensions that are supported by all Gallium drivers:
    */
   ctx->Extensions.ARB_ES2_compatibility = GL_TRUE;
   ctx->Extensions.ARB_draw_elements_base_vertex = GL_TRUE;
   ctx->Extensions.ARB_explicit_attrib_location = GL_TRUE;
   ctx->Extensions.ARB_fragment_coord_conventions = GL_TRUE;
   ctx->Extensions.ARB_fragment_program = GL_TRUE;
   ctx->Extensions.ARB_fragment_shader = GL_TRUE;
   ctx->Extensions.ARB_half_float_pixel = GL_TRUE;
   ctx->Extensions.ARB_half_float_vertex = GL_TRUE;
   ctx->Extensions.ARB_internalformat_query = GL_TRUE;
   ctx->Extensions.ARB_map_buffer_range = GL_TRUE;
   ctx->Extensions.ARB_texture_border_clamp = GL_TRUE; /* XXX temp */
   ctx->Extensions.ARB_texture_cube_map = GL_TRUE;
   ctx->Extensions.ARB_texture_env_combine = GL_TRUE;
   ctx->Extensions.ARB_texture_env_crossbar = GL_TRUE;
   ctx->Extensions.ARB_texture_env_dot3 = GL_TRUE;
   ctx->Extensions.ARB_vertex_program = GL_TRUE;
   ctx->Extensions.ARB_vertex_shader = GL_TRUE;

   ctx->Extensions.EXT_blend_color = GL_TRUE;
   ctx->Extensions.EXT_blend_func_separate = GL_TRUE;
   ctx->Extensions.EXT_blend_minmax = GL_TRUE;
   ctx->Extensions.EXT_gpu_program_parameters = GL_TRUE;
   ctx->Extensions.EXT_pixel_buffer_object = GL_TRUE;
   ctx->Extensions.EXT_point_parameters = GL_TRUE;
   ctx->Extensions.EXT_provoking_vertex = GL_TRUE;

   /* IMPORTANT:
    *    Don't enable EXT_separate_shader_objects. It disallows a certain
    *    optimization in the GLSL compiler and therefore is considered
    *    harmful.
    */
   ctx->Extensions.EXT_separate_shader_objects = GL_FALSE;

   ctx->Extensions.EXT_texture_env_dot3 = GL_TRUE;
   ctx->Extensions.EXT_vertex_array_bgra = GL_TRUE;

   ctx->Extensions.ATI_texture_env_combine3 = GL_TRUE;

   ctx->Extensions.MESA_pack_invert = GL_TRUE;

   ctx->Extensions.NV_fog_distance = GL_TRUE;
   ctx->Extensions.NV_texture_env_combine4 = GL_TRUE;
   ctx->Extensions.NV_texture_rectangle = GL_TRUE;
   ctx->Extensions.NV_vdpau_interop = GL_TRUE;

   ctx->Extensions.OES_EGL_image = GL_TRUE;
   ctx->Extensions.OES_EGL_image_external = GL_TRUE;
   ctx->Extensions.OES_draw_texture = GL_TRUE;

   /* Expose the extensions which directly correspond to gallium caps. */
   for (i = 0; i < Elements(cap_mapping); i++) {
      if (screen->get_param(screen, cap_mapping[i].cap)) {
         extensions[cap_mapping[i].extension_offset] = GL_TRUE;
      }
   }

   /* Expose the extensions which directly correspond to gallium formats. */
   init_format_extensions(st, rendertarget_mapping,
                          Elements(rendertarget_mapping), PIPE_TEXTURE_2D,
                          PIPE_BIND_RENDER_TARGET | PIPE_BIND_SAMPLER_VIEW);
   init_format_extensions(st, depthstencil_mapping,
                          Elements(depthstencil_mapping), PIPE_TEXTURE_2D,
                          PIPE_BIND_DEPTH_STENCIL | PIPE_BIND_SAMPLER_VIEW);
   init_format_extensions(st, texture_mapping, Elements(texture_mapping),
                          PIPE_TEXTURE_2D, PIPE_BIND_SAMPLER_VIEW);
   init_format_extensions(st, vertex_mapping, Elements(vertex_mapping),
                          PIPE_BUFFER, PIPE_BIND_VERTEX_BUFFER);

   /* Figure out GLSL support. */
   glsl_feature_level = screen->get_param(screen, PIPE_CAP_GLSL_FEATURE_LEVEL);

   ctx->Const.GLSLVersion = glsl_feature_level;
   if (glsl_feature_level >= 330)
      ctx->Const.GLSLVersion = 330;

   _mesa_override_glsl_version(st->ctx);

   if (st->options.force_glsl_version > 0 &&
       st->options.force_glsl_version <= ctx->Const.GLSLVersion) {
      ctx->Const.ForceGLSLVersion = st->options.force_glsl_version;
   }

   /* This extension needs full OpenGL 3.2, but we don't know if that's
    * supported at this point. Only check the GLSL version. */
   if (ctx->Const.GLSLVersion >= 150 &&
       screen->get_param(screen, PIPE_CAP_TGSI_VS_LAYER)) {
      ctx->Extensions.AMD_vertex_shader_layer = GL_TRUE;
   }

   if (ctx->Const.GLSLVersion >= 130) {
      ctx->Const.NativeIntegers = GL_TRUE;
      ctx->Const.MaxClipPlanes = 8;

      /* Extensions that either depend on GLSL 1.30 or are a subset thereof. */
      ctx->Extensions.ARB_conservative_depth = GL_TRUE;
      ctx->Extensions.ARB_shading_language_packing = GL_TRUE;
      ctx->Extensions.OES_depth_texture_cube_map = GL_TRUE;
      ctx->Extensions.ARB_shading_language_420pack = GL_TRUE;

      if (!st->options.disable_shader_bit_encoding) {
         ctx->Extensions.ARB_shader_bit_encoding = GL_TRUE;
      }
   } else {
      /* Optional integer support for GLSL 1.2. */
      if (screen->get_shader_param(screen, PIPE_SHADER_VERTEX,
                                   PIPE_SHADER_CAP_INTEGERS) &&
          screen->get_shader_param(screen, PIPE_SHADER_FRAGMENT,
                                   PIPE_SHADER_CAP_INTEGERS)) {
         ctx->Const.NativeIntegers = GL_TRUE;
      }
   }

   /* Below are the cases which cannot be moved into tables easily. */

   if (!ctx->Mesa_DXTn && !st->options.force_s3tc_enable) {
      ctx->Extensions.EXT_texture_compression_s3tc = GL_FALSE;
      ctx->Extensions.ANGLE_texture_compression_dxt = GL_FALSE;
   }

   if (screen->get_shader_param(screen, PIPE_SHADER_GEOMETRY,
                                PIPE_SHADER_CAP_MAX_INSTRUCTIONS) > 0) {
#if 0 /* XXX re-enable when GLSL compiler again supports geometry shaders */
      ctx->Extensions.ARB_geometry_shader4 = GL_TRUE;
#endif
   }

   ctx->Extensions.NV_primitive_restart = GL_TRUE;
   if (!screen->get_param(screen, PIPE_CAP_PRIMITIVE_RESTART)) {
      ctx->Const.PrimitiveRestartInSoftware = GL_TRUE;
   }

   /* ARB_color_buffer_float. */
   if (screen->get_param(screen, PIPE_CAP_VERTEX_COLOR_UNCLAMPED)) {
      ctx->Extensions.ARB_color_buffer_float = GL_TRUE;

      if (!screen->get_param(screen, PIPE_CAP_VERTEX_COLOR_CLAMPED)) {
         st->clamp_vert_color_in_shader = TRUE;
      }

      if (!screen->get_param(screen, PIPE_CAP_FRAGMENT_COLOR_CLAMPED)) {
         st->clamp_frag_color_in_shader = TRUE;
      }

      /* For drivers which cannot do color clamping, it's better to just
       * disable ARB_color_buffer_float in the core profile, because
       * the clamping is deprecated there anyway. */
      if (ctx->API == API_OPENGL_CORE &&
          (st->clamp_frag_color_in_shader || st->clamp_vert_color_in_shader)) {
         st->clamp_vert_color_in_shader = GL_FALSE;
         st->clamp_frag_color_in_shader = GL_FALSE;
         ctx->Extensions.ARB_color_buffer_float = GL_FALSE;
      }
   }

   if (screen->fence_finish) {
      ctx->Extensions.ARB_sync = GL_TRUE;
   }

   /* Maximum sample count. */
   for (i = 16; i > 0; --i) {
      enum pipe_format pformat = st_choose_format(st, GL_RGBA,
                                                  GL_NONE, GL_NONE,
                                                  PIPE_TEXTURE_2D, i,
                                                  PIPE_BIND_RENDER_TARGET, FALSE);
      if (pformat != PIPE_FORMAT_NONE) {
         ctx->Const.MaxSamples = i;
         ctx->Const.MaxColorTextureSamples = i;
         break;
      }
   }
   for (i = ctx->Const.MaxSamples; i > 0; --i) {
      enum pipe_format pformat = st_choose_format(st, GL_DEPTH_STENCIL,
                                                  GL_NONE, GL_NONE,
                                                  PIPE_TEXTURE_2D, i,
                                                  PIPE_BIND_DEPTH_STENCIL, FALSE);
      if (pformat != PIPE_FORMAT_NONE) {
         ctx->Const.MaxDepthTextureSamples = i;
         break;
      }
   }
   for (i = ctx->Const.MaxSamples; i > 0; --i) {
      enum pipe_format pformat = st_choose_format(st, GL_RGBA_INTEGER,
                                                  GL_NONE, GL_NONE,
                                                  PIPE_TEXTURE_2D, i,
                                                  PIPE_BIND_RENDER_TARGET, FALSE);
      if (pformat != PIPE_FORMAT_NONE) {
         ctx->Const.MaxIntegerSamples = i;
         break;
      }
   }
   if (ctx->Const.MaxSamples == 1) {
      /* one sample doesn't really make sense */
      ctx->Const.MaxSamples = 0;
   }
   else if (ctx->Const.MaxSamples >= 2) {
      ctx->Extensions.EXT_framebuffer_multisample = GL_TRUE;
      ctx->Extensions.EXT_framebuffer_multisample_blit_scaled = GL_TRUE;
   }

   if (ctx->Const.MaxDualSourceDrawBuffers > 0 &&
       !st->options.disable_blend_func_extended)
      ctx->Extensions.ARB_blend_func_extended = GL_TRUE;

   st->has_time_elapsed =
      screen->get_param(screen, PIPE_CAP_QUERY_TIME_ELAPSED);

   if (st->has_time_elapsed ||
       ctx->Extensions.ARB_timer_query) {
      ctx->Extensions.EXT_timer_query = GL_TRUE;
   }

   if (ctx->Extensions.ARB_transform_feedback2 &&
       ctx->Extensions.ARB_draw_instanced) {
      ctx->Extensions.ARB_transform_feedback_instanced = GL_TRUE;
   }
   if (st->options.force_glsl_extensions_warn)
      ctx->Const.ForceGLSLExtensionsWarn = 1;

   if (st->options.disable_glsl_line_continuations)
      ctx->Const.DisableGLSLLineContinuations = 1;

   ctx->Const.MinMapBufferAlignment =
      screen->get_param(screen, PIPE_CAP_MIN_MAP_BUFFER_ALIGNMENT);

   if (screen->get_param(screen, PIPE_CAP_TEXTURE_BUFFER_OBJECTS)) {
      ctx->Extensions.ARB_texture_buffer_object = GL_TRUE;

      ctx->Const.MaxTextureBufferSize =
         _min(screen->get_param(screen, PIPE_CAP_MAX_TEXTURE_BUFFER_SIZE),
              (1u << 31) - 1);
      ctx->Const.TextureBufferOffsetAlignment =
         screen->get_param(screen, PIPE_CAP_TEXTURE_BUFFER_OFFSET_ALIGNMENT);

      if (ctx->Const.TextureBufferOffsetAlignment)
         ctx->Extensions.ARB_texture_buffer_range = GL_TRUE;

      init_format_extensions(st, tbo_rgb32, Elements(tbo_rgb32),
                             PIPE_BUFFER, PIPE_BIND_SAMPLER_VIEW);
   }

   if (screen->get_param(screen, PIPE_CAP_MIXED_FRAMEBUFFER_SIZES)) {
      ctx->Extensions.ARB_framebuffer_object = GL_TRUE;
   }

   /* Unpacking a varying in the fragment shader costs 1 texture indirection.
    * If the number of available texture indirections is very limited, then we
    * prefer to disable varying packing rather than run the risk of varying
    * packing preventing a shader from running.
    */
   if (screen->get_shader_param(screen, PIPE_SHADER_FRAGMENT,
                                PIPE_SHADER_CAP_MAX_TEX_INDIRECTIONS) <= 8) {
      /* We can't disable varying packing if transform feedback is available,
       * because transform feedback code assumes a packed varying layout.
       */
      if (!ctx->Extensions.EXT_transform_feedback)
         ctx->Const.DisableVaryingPacking = GL_TRUE;
   }
}