aboutsummaryrefslogtreecommitdiff
path: root/mesalib/src/mesa/swrast/s_context.c
blob: 53497bc9c40826a3046489c9db70c4a3a26f091a (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
/*
 * Mesa 3-D graphics library
 * Version:  7.1
 *
 * Copyright (C) 1999-2008  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.
 *
 * Authors:
 *    Keith Whitwell <keith@tungstengraphics.com>
 *    Brian Paul
 */

#include "main/imports.h"
#include "main/bufferobj.h"
#include "main/colormac.h"
#include "main/mtypes.h"
#include "main/samplerobj.h"
#include "main/teximage.h"
#include "program/prog_parameter.h"
#include "program/prog_statevars.h"
#include "swrast.h"
#include "s_blend.h"
#include "s_context.h"
#include "s_lines.h"
#include "s_points.h"
#include "s_span.h"
#include "s_texfetch.h"
#include "s_triangle.h"
#include "s_texfilter.h"


/**
 * Recompute the value of swrast->_RasterMask, etc. according to
 * the current context.  The _RasterMask field can be easily tested by
 * drivers to determine certain basic GL state (does the primitive need
 * stenciling, logic-op, fog, etc?).
 */
static void
_swrast_update_rasterflags( struct gl_context *ctx )
{
   SWcontext *swrast = SWRAST_CONTEXT(ctx);
   GLbitfield rasterMask = 0;
   GLuint i;

   if (ctx->Color.AlphaEnabled)           rasterMask |= ALPHATEST_BIT;
   if (ctx->Color.BlendEnabled)           rasterMask |= BLEND_BIT;
   if (ctx->Depth.Test)                   rasterMask |= DEPTH_BIT;
   if (swrast->_FogEnabled)               rasterMask |= FOG_BIT;
   if (ctx->Scissor.Enabled)              rasterMask |= CLIP_BIT;
   if (ctx->Stencil._Enabled)             rasterMask |= STENCIL_BIT;
   for (i = 0; i < ctx->Const.MaxDrawBuffers; i++) {
      if (!ctx->Color.ColorMask[i][0] ||
          !ctx->Color.ColorMask[i][1] ||
          !ctx->Color.ColorMask[i][2] ||
          !ctx->Color.ColorMask[i][3]) {
         rasterMask |= MASKING_BIT;
         break;
      }
   }
   if (ctx->Color.ColorLogicOpEnabled) rasterMask |= LOGIC_OP_BIT;
   if (ctx->Texture._EnabledUnits)     rasterMask |= TEXTURE_BIT;
   if (   ctx->Viewport.X < 0
       || ctx->Viewport.X + ctx->Viewport.Width > (GLint) ctx->DrawBuffer->Width
       || ctx->Viewport.Y < 0
       || ctx->Viewport.Y + ctx->Viewport.Height > (GLint) ctx->DrawBuffer->Height) {
      rasterMask |= CLIP_BIT;
   }

   if (ctx->Query.CurrentOcclusionObject)
      rasterMask |= OCCLUSION_BIT;


   /* If we're not drawing to exactly one color buffer set the
    * MULTI_DRAW_BIT flag.  Also set it if we're drawing to no
    * buffers or the RGBA or CI mask disables all writes.
    */
   if (ctx->DrawBuffer->_NumColorDrawBuffers != 1) {
      /* more than one color buffer designated for writing (or zero buffers) */
      rasterMask |= MULTI_DRAW_BIT;
   }

   for (i = 0; i < ctx->Const.MaxDrawBuffers; i++) {
      if (ctx->Color.ColorMask[i][0] +
          ctx->Color.ColorMask[i][1] +
          ctx->Color.ColorMask[i][2] +
          ctx->Color.ColorMask[i][3] == 0) {
         rasterMask |= MULTI_DRAW_BIT; /* all RGBA channels disabled */
         break;
      }
   }


   if (_swrast_use_fragment_program(ctx)) {
      rasterMask |= FRAGPROG_BIT;
   }

   if (ctx->ATIFragmentShader._Enabled) {
      rasterMask |= ATIFRAGSHADER_BIT;
   }

#if CHAN_TYPE == GL_FLOAT
   if (ctx->Color.ClampFragmentColor == GL_TRUE) {
      rasterMask |= CLAMPING_BIT;
   }
#endif

   SWRAST_CONTEXT(ctx)->_RasterMask = rasterMask;
}


/**
 * Examine polygon cull state to compute the _BackfaceCullSign field.
 * _BackfaceCullSign will be 0 if no culling, -1 if culling back-faces,
 * and 1 if culling front-faces.  The Polygon FrontFace state also
 * factors in.
 */
static void
_swrast_update_polygon( struct gl_context *ctx )
{
   GLfloat backface_sign;

   if (ctx->Polygon.CullFlag) {
      switch (ctx->Polygon.CullFaceMode) {
      case GL_BACK:
         backface_sign = -1.0F;
	 break;
      case GL_FRONT:
         backface_sign = 1.0F;
	 break;
      case GL_FRONT_AND_BACK:
         /* fallthrough */
      default:
	 backface_sign = 0.0F;
      }
   }
   else {
      backface_sign = 0.0F;
   }

   SWRAST_CONTEXT(ctx)->_BackfaceCullSign = backface_sign;

   /* This is for front/back-face determination, but not for culling */
   SWRAST_CONTEXT(ctx)->_BackfaceSign
      = (ctx->Polygon.FrontFace == GL_CW) ? -1.0F : 1.0F;
}



/**
 * Update the _PreferPixelFog field to indicate if we need to compute
 * fog blend factors (from the fog coords) per-fragment.
 */
static void
_swrast_update_fog_hint( struct gl_context *ctx )
{
   SWcontext *swrast = SWRAST_CONTEXT(ctx);
   swrast->_PreferPixelFog = (!swrast->AllowVertexFog ||
			      _swrast_use_fragment_program(ctx) ||
			      (ctx->Hint.Fog == GL_NICEST &&
			       swrast->AllowPixelFog));
}



/**
 * Update the swrast->_TextureCombinePrimary flag.
 */
static void
_swrast_update_texture_env( struct gl_context *ctx )
{
   SWcontext *swrast = SWRAST_CONTEXT(ctx);
   GLuint i;

   swrast->_TextureCombinePrimary = GL_FALSE;

   for (i = 0; i < ctx->Const.MaxTextureUnits; i++) {
      const struct gl_tex_env_combine_state *combine =
         ctx->Texture.Unit[i]._CurrentCombine;
      GLuint term;
      for (term = 0; term < combine->_NumArgsRGB; term++) {
         if (combine->SourceRGB[term] == GL_PRIMARY_COLOR) {
            swrast->_TextureCombinePrimary = GL_TRUE;
            return;
         }
         if (combine->SourceA[term] == GL_PRIMARY_COLOR) {
            swrast->_TextureCombinePrimary = GL_TRUE;
            return;
         }
      }
   }
}


/**
 * Determine if we can defer texturing/shading until after Z/stencil
 * testing.  This potentially allows us to skip texturing/shading for
 * lots of fragments.
 */
static void
_swrast_update_deferred_texture(struct gl_context *ctx)
{
   SWcontext *swrast = SWRAST_CONTEXT(ctx);
   if (ctx->Color.AlphaEnabled) {
      /* alpha test depends on post-texture/shader colors */
      swrast->_DeferredTexture = GL_FALSE;
   }
   else {
      GLboolean use_fprog = _swrast_use_fragment_program(ctx);
      const struct gl_fragment_program *fprog
         = ctx->FragmentProgram._Current;
      if (use_fprog && (fprog->Base.OutputsWritten & (1 << FRAG_RESULT_DEPTH))) {
         /* Z comes from fragment program/shader */
         swrast->_DeferredTexture = GL_FALSE;
      }
      else if (use_fprog && fprog->UsesKill) {
         swrast->_DeferredTexture = GL_FALSE;
      }
      else if (ctx->Query.CurrentOcclusionObject) {
         /* occlusion query depends on shader discard/kill results */
         swrast->_DeferredTexture = GL_FALSE;
      }
      else {
         swrast->_DeferredTexture = GL_TRUE;
      }
   }
}


/**
 * Update swrast->_FogColor and swrast->_FogEnable values.
 */
static void
_swrast_update_fog_state( struct gl_context *ctx )
{
   SWcontext *swrast = SWRAST_CONTEXT(ctx);
   const struct gl_fragment_program *fp = ctx->FragmentProgram._Current;

   assert((fp == NULL) ||
          (fp->Base.Target == GL_FRAGMENT_PROGRAM_ARB) ||
          (fp->Base.Target == GL_FRAGMENT_PROGRAM_NV));

   /* determine if fog is needed, and if so, which fog mode */
   swrast->_FogEnabled = (!_swrast_use_fragment_program(ctx) &&
			  ctx->Fog.Enabled);
}


/**
 * Update state for running fragment programs.  Basically, load the
 * program parameters with current state values.
 */
static void
_swrast_update_fragment_program(struct gl_context *ctx, GLbitfield newState)
{
   if (!_swrast_use_fragment_program(ctx))
      return;

   _mesa_load_state_parameters(ctx,
                               ctx->FragmentProgram._Current->Base.Parameters);
}


/**
 * See if we can do early diffuse+specular (primary+secondary) color
 * add per vertex instead of per-fragment.
 */
static void
_swrast_update_specular_vertex_add(struct gl_context *ctx)
{
   SWcontext *swrast = SWRAST_CONTEXT(ctx);
   GLboolean separateSpecular = ctx->Fog.ColorSumEnabled ||
      (ctx->Light.Enabled &&
       ctx->Light.Model.ColorControl == GL_SEPARATE_SPECULAR_COLOR);

   swrast->SpecularVertexAdd = (separateSpecular
                                && ctx->Texture._EnabledUnits == 0x0
                                && !_swrast_use_fragment_program(ctx)
                                && !ctx->ATIFragmentShader._Enabled);
}


#define _SWRAST_NEW_DERIVED (_SWRAST_NEW_RASTERMASK |	\
                             _NEW_PROGRAM_CONSTANTS |   \
			     _NEW_TEXTURE |		\
			     _NEW_HINT |		\
			     _NEW_POLYGON )

/* State referenced by _swrast_choose_triangle, _swrast_choose_line.
 */
#define _SWRAST_NEW_TRIANGLE (_SWRAST_NEW_DERIVED |		\
			      _NEW_RENDERMODE|			\
                              _NEW_POLYGON|			\
                              _NEW_DEPTH|			\
                              _NEW_STENCIL|			\
                              _NEW_COLOR|			\
                              _NEW_TEXTURE|			\
                              _SWRAST_NEW_RASTERMASK|		\
                              _NEW_LIGHT|			\
                              _NEW_FOG |			\
			      _MESA_NEW_SEPARATE_SPECULAR)

#define _SWRAST_NEW_LINE (_SWRAST_NEW_DERIVED |		\
			  _NEW_RENDERMODE|		\
                          _NEW_LINE|			\
                          _NEW_TEXTURE|			\
                          _NEW_LIGHT|			\
                          _NEW_FOG|			\
                          _NEW_DEPTH |			\
                          _MESA_NEW_SEPARATE_SPECULAR)

#define _SWRAST_NEW_POINT (_SWRAST_NEW_DERIVED |	\
			   _NEW_RENDERMODE |		\
			   _NEW_POINT |			\
			   _NEW_TEXTURE |		\
			   _NEW_LIGHT |			\
			   _NEW_FOG |			\
                           _MESA_NEW_SEPARATE_SPECULAR)

#define _SWRAST_NEW_TEXTURE_SAMPLE_FUNC _NEW_TEXTURE

#define _SWRAST_NEW_TEXTURE_ENV_MODE _NEW_TEXTURE

#define _SWRAST_NEW_BLEND_FUNC _NEW_COLOR



/**
 * Stub for swrast->Triangle to select a true triangle function
 * after a state change.
 */
static void
_swrast_validate_triangle( struct gl_context *ctx,
			   const SWvertex *v0,
                           const SWvertex *v1,
                           const SWvertex *v2 )
{
   SWcontext *swrast = SWRAST_CONTEXT(ctx);

   _swrast_validate_derived( ctx );
   swrast->choose_triangle( ctx );
   ASSERT(swrast->Triangle);

   if (swrast->SpecularVertexAdd) {
      /* separate specular color, but no texture */
      swrast->SpecTriangle = swrast->Triangle;
      swrast->Triangle = _swrast_add_spec_terms_triangle;
   }

   swrast->Triangle( ctx, v0, v1, v2 );
}

/**
 * Called via swrast->Line.  Examine current GL state and choose a software
 * line routine.  Then call it.
 */
static void
_swrast_validate_line( struct gl_context *ctx, const SWvertex *v0, const SWvertex *v1 )
{
   SWcontext *swrast = SWRAST_CONTEXT(ctx);

   _swrast_validate_derived( ctx );
   swrast->choose_line( ctx );
   ASSERT(swrast->Line);

   if (swrast->SpecularVertexAdd) {
      swrast->SpecLine = swrast->Line;
      swrast->Line = _swrast_add_spec_terms_line;
   }

   swrast->Line( ctx, v0, v1 );
}

/**
 * Called via swrast->Point.  Examine current GL state and choose a software
 * point routine.  Then call it.
 */
static void
_swrast_validate_point( struct gl_context *ctx, const SWvertex *v0 )
{
   SWcontext *swrast = SWRAST_CONTEXT(ctx);

   _swrast_validate_derived( ctx );
   swrast->choose_point( ctx );

   if (swrast->SpecularVertexAdd) {
      swrast->SpecPoint = swrast->Point;
      swrast->Point = _swrast_add_spec_terms_point;
   }

   swrast->Point( ctx, v0 );
}


/**
 * Called via swrast->BlendFunc.  Examine GL state to choose a blending
 * function, then call it.
 */
static void _ASMAPI
_swrast_validate_blend_func(struct gl_context *ctx, GLuint n, const GLubyte mask[],
                            GLvoid *src, const GLvoid *dst,
                            GLenum chanType )
{
   SWcontext *swrast = SWRAST_CONTEXT(ctx);

   _swrast_validate_derived( ctx ); /* why is this needed? */
   _swrast_choose_blend_func( ctx, chanType );

   swrast->BlendFunc( ctx, n, mask, src, dst, chanType );
}

static void
_swrast_sleep( struct gl_context *ctx, GLbitfield new_state )
{
   (void) ctx; (void) new_state;
}


static void
_swrast_invalidate_state( struct gl_context *ctx, GLbitfield new_state )
{
   SWcontext *swrast = SWRAST_CONTEXT(ctx);
   GLuint i;

   swrast->NewState |= new_state;

   /* After 10 statechanges without any swrast functions being called,
    * put the module to sleep.
    */
   if (++swrast->StateChanges > 10) {
      swrast->InvalidateState = _swrast_sleep;
      swrast->NewState = ~0;
      new_state = ~0;
   }

   if (new_state & swrast->InvalidateTriangleMask)
      swrast->Triangle = _swrast_validate_triangle;

   if (new_state & swrast->InvalidateLineMask)
      swrast->Line = _swrast_validate_line;

   if (new_state & swrast->InvalidatePointMask)
      swrast->Point = _swrast_validate_point;

   if (new_state & _SWRAST_NEW_BLEND_FUNC)
      swrast->BlendFunc = _swrast_validate_blend_func;

   if (new_state & _SWRAST_NEW_TEXTURE_SAMPLE_FUNC)
      for (i = 0 ; i < ctx->Const.MaxTextureImageUnits ; i++)
	 swrast->TextureSample[i] = NULL;
}


void
_swrast_update_texture_samplers(struct gl_context *ctx)
{
   SWcontext *swrast = SWRAST_CONTEXT(ctx);
   GLuint u;

   if (!swrast)
      return; /* pipe hack */

   for (u = 0; u < ctx->Const.MaxTextureImageUnits; u++) {
      struct gl_texture_object *tObj = ctx->Texture.Unit[u]._Current;
      /* Note: If tObj is NULL, the sample function will be a simple
       * function that just returns opaque black (0,0,0,1).
       */
      _mesa_update_fetch_functions(ctx, u);
      swrast->TextureSample[u] =
         _swrast_choose_texture_sample_func(ctx, tObj,
                                            _mesa_get_samplerobj(ctx, u));
   }
}


/**
 * Update swrast->_ActiveAttribs, swrast->_NumActiveAttribs,
 * swrast->_ActiveAtttribMask.
 */
static void
_swrast_update_active_attribs(struct gl_context *ctx)
{
   SWcontext *swrast = SWRAST_CONTEXT(ctx);
   GLbitfield64 attribsMask;

   /*
    * Compute _ActiveAttribsMask = which fragment attributes are needed.
    */
   if (_swrast_use_fragment_program(ctx)) {
      /* fragment program/shader */
      attribsMask = ctx->FragmentProgram._Current->Base.InputsRead;
      attribsMask &= ~FRAG_BIT_WPOS; /* WPOS is always handled specially */
   }
   else if (ctx->ATIFragmentShader._Enabled) {
      attribsMask = ~0;  /* XXX fix me */
   }
   else {
      /* fixed function */
      attribsMask = 0x0;

#if CHAN_TYPE == GL_FLOAT
      attribsMask |= FRAG_BIT_COL0;
#endif

      if (ctx->Fog.ColorSumEnabled ||
          (ctx->Light.Enabled &&
           ctx->Light.Model.ColorControl == GL_SEPARATE_SPECULAR_COLOR)) {
         attribsMask |= FRAG_BIT_COL1;
      }

      if (swrast->_FogEnabled)
         attribsMask |= FRAG_BIT_FOGC;

      attribsMask |= (ctx->Texture._EnabledUnits << FRAG_ATTRIB_TEX0);
   }

   swrast->_ActiveAttribMask = attribsMask;

   /* Update _ActiveAttribs[] list */
   {
      GLuint i, num = 0;
      for (i = 0; i < FRAG_ATTRIB_MAX; i++) {
         if (attribsMask & BITFIELD64_BIT(i)) {
            swrast->_ActiveAttribs[num++] = i;
            /* how should this attribute be interpolated? */
            if (i == FRAG_ATTRIB_COL0 || i == FRAG_ATTRIB_COL1)
               swrast->_InterpMode[i] = ctx->Light.ShadeModel;
            else
               swrast->_InterpMode[i] = GL_SMOOTH;
         }
      }
      swrast->_NumActiveAttribs = num;
   }
}


void
_swrast_validate_derived( struct gl_context *ctx )
{
   SWcontext *swrast = SWRAST_CONTEXT(ctx);

   if (swrast->NewState) {
      if (swrast->NewState & _NEW_POLYGON)
	 _swrast_update_polygon( ctx );

      if (swrast->NewState & (_NEW_HINT | _NEW_PROGRAM))
	 _swrast_update_fog_hint( ctx );

      if (swrast->NewState & _SWRAST_NEW_TEXTURE_ENV_MODE)
	 _swrast_update_texture_env( ctx );

      if (swrast->NewState & (_NEW_FOG | _NEW_PROGRAM))
         _swrast_update_fog_state( ctx );

      if (swrast->NewState & (_NEW_PROGRAM_CONSTANTS | _NEW_PROGRAM))
	 _swrast_update_fragment_program( ctx, swrast->NewState );

      if (swrast->NewState & (_NEW_TEXTURE | _NEW_PROGRAM)) {
         _swrast_update_texture_samplers( ctx );
      }

      if (swrast->NewState & (_NEW_COLOR | _NEW_PROGRAM))
         _swrast_update_deferred_texture(ctx);

      if (swrast->NewState & _SWRAST_NEW_RASTERMASK)
 	 _swrast_update_rasterflags( ctx );

      if (swrast->NewState & (_NEW_DEPTH |
                              _NEW_FOG |
                              _NEW_LIGHT |
                              _NEW_PROGRAM |
                              _NEW_TEXTURE))
         _swrast_update_active_attribs(ctx);

      if (swrast->NewState & (_NEW_FOG | 
                              _NEW_PROGRAM |
                              _NEW_LIGHT |
                              _NEW_TEXTURE))
         _swrast_update_specular_vertex_add(ctx);

      swrast->NewState = 0;
      swrast->StateChanges = 0;
      swrast->InvalidateState = _swrast_invalidate_state;
   }
}

#define SWRAST_DEBUG 0

/* Public entrypoints:  See also s_bitmap.c, etc.
 */
void
_swrast_Quad( struct gl_context *ctx,
	      const SWvertex *v0, const SWvertex *v1,
              const SWvertex *v2, const SWvertex *v3 )
{
   if (SWRAST_DEBUG) {
      _mesa_debug(ctx, "_swrast_Quad\n");
      _swrast_print_vertex( ctx, v0 );
      _swrast_print_vertex( ctx, v1 );
      _swrast_print_vertex( ctx, v2 );
      _swrast_print_vertex( ctx, v3 );
   }
   SWRAST_CONTEXT(ctx)->Triangle( ctx, v0, v1, v3 );
   SWRAST_CONTEXT(ctx)->Triangle( ctx, v1, v2, v3 );
}

void
_swrast_Triangle( struct gl_context *ctx, const SWvertex *v0,
                  const SWvertex *v1, const SWvertex *v2 )
{
   if (SWRAST_DEBUG) {
      _mesa_debug(ctx, "_swrast_Triangle\n");
      _swrast_print_vertex( ctx, v0 );
      _swrast_print_vertex( ctx, v1 );
      _swrast_print_vertex( ctx, v2 );
   }
   SWRAST_CONTEXT(ctx)->Triangle( ctx, v0, v1, v2 );
}

void
_swrast_Line( struct gl_context *ctx, const SWvertex *v0, const SWvertex *v1 )
{
   if (SWRAST_DEBUG) {
      _mesa_debug(ctx, "_swrast_Line\n");
      _swrast_print_vertex( ctx, v0 );
      _swrast_print_vertex( ctx, v1 );
   }
   SWRAST_CONTEXT(ctx)->Line( ctx, v0, v1 );
}

void
_swrast_Point( struct gl_context *ctx, const SWvertex *v0 )
{
   if (SWRAST_DEBUG) {
      _mesa_debug(ctx, "_swrast_Point\n");
      _swrast_print_vertex( ctx, v0 );
   }
   SWRAST_CONTEXT(ctx)->Point( ctx, v0 );
}

void
_swrast_InvalidateState( struct gl_context *ctx, GLbitfield new_state )
{
   if (SWRAST_DEBUG) {
      _mesa_debug(ctx, "_swrast_InvalidateState\n");
   }
   SWRAST_CONTEXT(ctx)->InvalidateState( ctx, new_state );
}

void
_swrast_ResetLineStipple( struct gl_context *ctx )
{
   if (SWRAST_DEBUG) {
      _mesa_debug(ctx, "_swrast_ResetLineStipple\n");
   }
   SWRAST_CONTEXT(ctx)->StippleCounter = 0;
}

void
_swrast_SetFacing(struct gl_context *ctx, GLuint facing)
{
   SWRAST_CONTEXT(ctx)->PointLineFacing = facing;
}

void
_swrast_allow_vertex_fog( struct gl_context *ctx, GLboolean value )
{
   if (SWRAST_DEBUG) {
      _mesa_debug(ctx, "_swrast_allow_vertex_fog %d\n", value);
   }
   SWRAST_CONTEXT(ctx)->InvalidateState( ctx, _NEW_HINT );
   SWRAST_CONTEXT(ctx)->AllowVertexFog = value;
}

void
_swrast_allow_pixel_fog( struct gl_context *ctx, GLboolean value )
{
   if (SWRAST_DEBUG) {
      _mesa_debug(ctx, "_swrast_allow_pixel_fog %d\n", value);
   }
   SWRAST_CONTEXT(ctx)->InvalidateState( ctx, _NEW_HINT );
   SWRAST_CONTEXT(ctx)->AllowPixelFog = value;
}


/**
 * Initialize native program limits by copying the logical limits.
 * See comments in init_program_limits() in context.c
 */
static void
init_program_native_limits(struct gl_program_constants *prog)
{
   prog->MaxNativeInstructions = prog->MaxInstructions;
   prog->MaxNativeAluInstructions = prog->MaxAluInstructions;
   prog->MaxNativeTexInstructions = prog->MaxTexInstructions;
   prog->MaxNativeTexIndirections = prog->MaxTexIndirections;
   prog->MaxNativeAttribs = prog->MaxAttribs;
   prog->MaxNativeTemps = prog->MaxTemps;
   prog->MaxNativeAddressRegs = prog->MaxAddressRegs;
   prog->MaxNativeParameters = prog->MaxParameters;
}


GLboolean
_swrast_CreateContext( struct gl_context *ctx )
{
   GLuint i;
   SWcontext *swrast = (SWcontext *) calloc(1, sizeof(SWcontext));
#ifdef _OPENMP
   const GLuint maxThreads = omp_get_max_threads();
#else
   const GLuint maxThreads = 1;
#endif

   assert(ctx->Const.MaxViewportWidth <= SWRAST_MAX_WIDTH);
   assert(ctx->Const.MaxViewportHeight <= SWRAST_MAX_WIDTH);

   assert(ctx->Const.MaxRenderbufferSize <= SWRAST_MAX_WIDTH);

   /* make sure largest texture image is <= SWRAST_MAX_WIDTH in size */
   assert((1 << (ctx->Const.MaxTextureLevels - 1)) <= SWRAST_MAX_WIDTH);
   assert((1 << (ctx->Const.MaxCubeTextureLevels - 1)) <= SWRAST_MAX_WIDTH);
   assert((1 << (ctx->Const.Max3DTextureLevels - 1)) <= SWRAST_MAX_WIDTH);

   assert(PROG_MAX_WIDTH == SWRAST_MAX_WIDTH);

   if (SWRAST_DEBUG) {
      _mesa_debug(ctx, "_swrast_CreateContext\n");
   }

   if (!swrast)
      return GL_FALSE;

   swrast->NewState = ~0;

   swrast->choose_point = _swrast_choose_point;
   swrast->choose_line = _swrast_choose_line;
   swrast->choose_triangle = _swrast_choose_triangle;

   swrast->InvalidatePointMask = _SWRAST_NEW_POINT;
   swrast->InvalidateLineMask = _SWRAST_NEW_LINE;
   swrast->InvalidateTriangleMask = _SWRAST_NEW_TRIANGLE;

   swrast->Point = _swrast_validate_point;
   swrast->Line = _swrast_validate_line;
   swrast->Triangle = _swrast_validate_triangle;
   swrast->InvalidateState = _swrast_sleep;
   swrast->BlendFunc = _swrast_validate_blend_func;

   swrast->AllowVertexFog = GL_TRUE;
   swrast->AllowPixelFog = GL_TRUE;

   swrast->Driver.SpanRenderStart = _swrast_span_render_start;
   swrast->Driver.SpanRenderFinish = _swrast_span_render_finish;

   for (i = 0; i < MAX_TEXTURE_IMAGE_UNITS; i++)
      swrast->TextureSample[i] = NULL;

   /* SpanArrays is global and shared by all SWspan instances. However, when
    * using multiple threads, it is necessary to have one SpanArrays instance
    * per thread.
    */
   swrast->SpanArrays = (SWspanarrays *) malloc(maxThreads * sizeof(SWspanarrays));
   if (!swrast->SpanArrays) {
      free(swrast);
      return GL_FALSE;
   }
   for(i = 0; i < maxThreads; i++) {
      swrast->SpanArrays[i].ChanType = CHAN_TYPE;
#if CHAN_TYPE == GL_UNSIGNED_BYTE
      swrast->SpanArrays[i].rgba = swrast->SpanArrays[i].rgba8;
#elif CHAN_TYPE == GL_UNSIGNED_SHORT
      swrast->SpanArrays[i].rgba = swrast->SpanArrays[i].rgba16;
#else
      swrast->SpanArrays[i].rgba = swrast->SpanArrays[i].attribs[FRAG_ATTRIB_COL0];
#endif
   }

   /* init point span buffer */
   swrast->PointSpan.primitive = GL_POINT;
   swrast->PointSpan.end = 0;
   swrast->PointSpan.facing = 0;
   swrast->PointSpan.array = swrast->SpanArrays;

   init_program_native_limits(&ctx->Const.VertexProgram);
   init_program_native_limits(&ctx->Const.GeometryProgram);
   init_program_native_limits(&ctx->Const.FragmentProgram);

   ctx->swrast_context = swrast;

   swrast->stencil_temp.buf1 = (GLubyte *) malloc(SWRAST_MAX_WIDTH * sizeof(GLubyte));
   swrast->stencil_temp.buf2 = (GLubyte *) malloc(SWRAST_MAX_WIDTH * sizeof(GLubyte));
   swrast->stencil_temp.buf3 = (GLubyte *) malloc(SWRAST_MAX_WIDTH * sizeof(GLubyte));
   swrast->stencil_temp.buf4 = (GLubyte *) malloc(SWRAST_MAX_WIDTH * sizeof(GLubyte));

   if (!swrast->stencil_temp.buf1 ||
       !swrast->stencil_temp.buf2 ||
       !swrast->stencil_temp.buf3 ||
       !swrast->stencil_temp.buf4) {
      _swrast_DestroyContext(ctx);
      return GL_FALSE;
   }

   return GL_TRUE;
}

void
_swrast_DestroyContext( struct gl_context *ctx )
{
   SWcontext *swrast = SWRAST_CONTEXT(ctx);

   if (SWRAST_DEBUG) {
      _mesa_debug(ctx, "_swrast_DestroyContext\n");
   }

   free( swrast->SpanArrays );
   if (swrast->ZoomedArrays)
      free( swrast->ZoomedArrays );
   free( swrast->TexelBuffer );

   free(swrast->stencil_temp.buf1);
   free(swrast->stencil_temp.buf2);
   free(swrast->stencil_temp.buf3);
   free(swrast->stencil_temp.buf4);

   free( swrast );

   ctx->swrast_context = 0;
}


struct swrast_device_driver *
_swrast_GetDeviceDriverReference( struct gl_context *ctx )
{
   SWcontext *swrast = SWRAST_CONTEXT(ctx);
   return &swrast->Driver;
}

void
_swrast_flush( struct gl_context *ctx )
{
   SWcontext *swrast = SWRAST_CONTEXT(ctx);
   /* flush any pending fragments from rendering points */
   if (swrast->PointSpan.end > 0) {
      _swrast_write_rgba_span(ctx, &(swrast->PointSpan));
      swrast->PointSpan.end = 0;
   }
}

void
_swrast_render_primitive( struct gl_context *ctx, GLenum prim )
{
   SWcontext *swrast = SWRAST_CONTEXT(ctx);
   if (swrast->Primitive == GL_POINTS && prim != GL_POINTS) {
      _swrast_flush(ctx);
   }
   swrast->Primitive = prim;
}


/** called via swrast->Driver.SpanRenderStart() */
void
_swrast_span_render_start(struct gl_context *ctx)
{
   _swrast_map_textures(ctx);
   _swrast_map_renderbuffers(ctx);
}


/** called via swrast->Driver.SpanRenderFinish() */
void
_swrast_span_render_finish(struct gl_context *ctx)
{
   _swrast_unmap_textures(ctx);
   _swrast_unmap_renderbuffers(ctx);
}


void
_swrast_render_start( struct gl_context *ctx )
{
   SWcontext *swrast = SWRAST_CONTEXT(ctx);
   if (swrast->Driver.SpanRenderStart)
      swrast->Driver.SpanRenderStart( ctx );
   swrast->PointSpan.end = 0;
}
 
void
_swrast_render_finish( struct gl_context *ctx )
{
   SWcontext *swrast = SWRAST_CONTEXT(ctx);

   _swrast_flush(ctx);

   if (swrast->Driver.SpanRenderFinish)
      swrast->Driver.SpanRenderFinish( ctx );
}


#define SWRAST_DEBUG_VERTICES 0

void
_swrast_print_vertex( struct gl_context *ctx, const SWvertex *v )
{
   GLuint i;

   if (SWRAST_DEBUG_VERTICES) {
      _mesa_debug(ctx, "win %f %f %f %f\n",
                  v->attrib[FRAG_ATTRIB_WPOS][0],
                  v->attrib[FRAG_ATTRIB_WPOS][1],
                  v->attrib[FRAG_ATTRIB_WPOS][2],
                  v->attrib[FRAG_ATTRIB_WPOS][3]);

      for (i = 0 ; i < ctx->Const.MaxTextureCoordUnits ; i++)
	 if (ctx->Texture.Unit[i]._ReallyEnabled)
	    _mesa_debug(ctx, "texcoord[%d] %f %f %f %f\n", i,
                        v->attrib[FRAG_ATTRIB_TEX0 + i][0],
                        v->attrib[FRAG_ATTRIB_TEX0 + i][1],
                        v->attrib[FRAG_ATTRIB_TEX0 + i][2],
                        v->attrib[FRAG_ATTRIB_TEX0 + i][3]);

#if CHAN_TYPE == GL_FLOAT
      _mesa_debug(ctx, "color %f %f %f %f\n",
                  v->color[0], v->color[1], v->color[2], v->color[3]);
#else
      _mesa_debug(ctx, "color %d %d %d %d\n",
                  v->color[0], v->color[1], v->color[2], v->color[3]);
#endif
      _mesa_debug(ctx, "spec %g %g %g %g\n",
                  v->attrib[FRAG_ATTRIB_COL1][0],
                  v->attrib[FRAG_ATTRIB_COL1][1],
                  v->attrib[FRAG_ATTRIB_COL1][2],
                  v->attrib[FRAG_ATTRIB_COL1][3]);
      _mesa_debug(ctx, "fog %f\n", v->attrib[FRAG_ATTRIB_FOGC][0]);
      _mesa_debug(ctx, "index %f\n", v->attrib[FRAG_ATTRIB_CI][0]);
      _mesa_debug(ctx, "pointsize %f\n", v->pointSize);
      _mesa_debug(ctx, "\n");
   }
}