src/mesa/swrast/s_context.c

   1 /* $Id: s_context.c,v 1.47 2003/03/15 17:33:27 brianp Exp $ */
   2
   3 /*
   4  * Mesa 3-D graphics library
   5  * Version:  5.1
   6  *
   7  * Copyright (C) 1999-2003  Brian Paul   All Rights Reserved.
   8  *
   9  * Permission is hereby granted, free of charge, to any person obtaining a
  10  * copy of this software and associated documentation files (the "Software"),
  11  * to deal in the Software without restriction, including without limitation
  12  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  13  * and/or sell copies of the Software, and to permit persons to whom the
  14  * Software is furnished to do so, subject to the following conditions:
  15  *
  16  * The above copyright notice and this permission notice shall be included
  17  * in all copies or substantial portions of the Software.
  18  *
  19  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  20  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  21  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  22  * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
  23  * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  24  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  25  *
  26  * Authors:
  27  *    Keith Whitwell <keith@tungstengraphics.com>
  28  *    Brian Paul
  29  */
  30
  31 #include "imports.h"
  32 #include "context.h"
  33 #include "mtypes.h"
  34 #include "texobj.h"
  35
  36 #include "swrast.h"
  37 #include "s_blend.h"
  38 #include "s_context.h"
  39 #include "s_lines.h"
  40 #include "s_points.h"
  41 #include "s_span.h"
  42 #include "s_triangle.h"
  43 #include "s_texture.h"
  44
  45
  46 /*
  47  * Recompute the value of swrast->_RasterMask, etc. according to
  48  * the current context.
  49  */
  50 static void
  51 _swrast_update_rasterflags( GLcontext *ctx )
  52 {
  53    GLuint RasterMask = 0;
  54
  55    if (ctx->Color.AlphaEnabled)           RasterMask |= ALPHATEST_BIT;
  56    if (ctx->Color.BlendEnabled)           RasterMask |= BLEND_BIT;
  57    if (ctx->Depth.Test)                   RasterMask |= DEPTH_BIT;
  58    if (ctx->Fog.Enabled)                  RasterMask |= FOG_BIT;
  59    if (ctx->Scissor.Enabled)              RasterMask |= CLIP_BIT;
  60    if (ctx->Stencil.Enabled)              RasterMask |= STENCIL_BIT;
  61    if (ctx->Visual.rgbMode) {
  62       const GLuint colorMask = *((GLuint *) &ctx->Color.ColorMask);
  63       if (colorMask != 0xffffffff)        RasterMask |= MASKING_BIT;
  64       if (ctx->Color.ColorLogicOpEnabled) RasterMask |= LOGIC_OP_BIT;
  65       if (ctx->Texture._EnabledUnits)     RasterMask |= TEXTURE_BIT;
  66    }
  67    else {
  68       if (ctx->Color.IndexMask != 0xffffffff) RasterMask |= MASKING_BIT;
  69       if (ctx->Color.IndexLogicOpEnabled)     RasterMask |= LOGIC_OP_BIT;
  70    }
  71
  72    if (ctx->DrawBuffer->UseSoftwareAlphaBuffers
  73        && ctx->Color.ColorMask[ACOMP]
  74        && ctx->Color.DrawBuffer != GL_NONE)
  75       RasterMask |= ALPHABUF_BIT;
  76
  77    if (   ctx->Viewport.X < 0
  78        || ctx->Viewport.X + ctx->Viewport.Width > (GLint) ctx->DrawBuffer->Width
  79        || ctx->Viewport.Y < 0
  80        || ctx->Viewport.Y + ctx->Viewport.Height > (GLint) ctx->DrawBuffer->Height) {
  81       RasterMask |= CLIP_BIT;
  82    }
  83
  84    if (ctx->Depth.OcclusionTest)
  85       RasterMask |= OCCLUSION_BIT;
  86
  87
  88    /* If we're not drawing to exactly one color buffer set the
  89     * MULTI_DRAW_BIT flag.  Also set it if we're drawing to no
  90     * buffers or the RGBA or CI mask disables all writes.
  91     */
  92    if (ctx->Color._DrawDestMask != FRONT_LEFT_BIT &&
  93        ctx->Color._DrawDestMask != BACK_LEFT_BIT &&
  94        ctx->Color._DrawDestMask != FRONT_RIGHT_BIT &&
  95        ctx->Color._DrawDestMask != BACK_RIGHT_BIT) {
  96       /* more than one color buffer designated for writing (or zero buffers) */
  97       RasterMask |= MULTI_DRAW_BIT;
  98    }
  99    else if (ctx->Visual.rgbMode && *((GLuint *) ctx->Color.ColorMask) == 0) {
 100       RasterMask |= MULTI_DRAW_BIT; /* all RGBA channels disabled */
 101    }
 102    else if (!ctx->Visual.rgbMode && ctx->Color.IndexMask==0) {
 103       RasterMask |= MULTI_DRAW_BIT; /* all color index bits disabled */
 104    }
 105
 106    SWRAST_CONTEXT(ctx)->_RasterMask = RasterMask;
 107 }
 108
 109
 110 static void
 111 _swrast_update_polygon( GLcontext *ctx )
 112 {
 113    GLfloat backface_sign = 1;
 114
 115    if (ctx->Polygon.CullFlag) {
 116       backface_sign = 1;
 117       switch(ctx->Polygon.CullFaceMode) {
 118       case GL_BACK:
 119          if(ctx->Polygon.FrontFace==GL_CCW)
 120             backface_sign = -1;
 121          break;
 122       case GL_FRONT:
 123          if(ctx->Polygon.FrontFace!=GL_CCW)
 124             backface_sign = -1;
 125          break;
 126       default:
 127       case GL_FRONT_AND_BACK:
 128          backface_sign = 0;
 129          break;
 130       }
 131    }
 132    else {
 133       backface_sign = 0;
 134    }
 135
 136    SWRAST_CONTEXT(ctx)->_backface_sign = backface_sign;
 137 }
 138
 139
 140 static void
 141 _swrast_update_hint( GLcontext *ctx )
 142 {
 143    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 144    swrast->_PreferPixelFog = (!swrast->AllowVertexFog ||
 145                               (ctx->Hint.Fog == GL_NICEST &&
 146                                swrast->AllowPixelFog));
 147 }
 148
 149
 150 /*
 151  * Update the swrast->_AnyTextureCombine flag.
 152  */
 153 static void
 154 _swrast_update_texture_env( GLcontext *ctx )
 155 {
 156    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 157    GLuint i;
 158    swrast->_AnyTextureCombine = GL_FALSE;
 159    for (i = 0; i < ctx->Const.MaxTextureUnits; i++) {
 160       if (ctx->Texture.Unit[i].EnvMode == GL_COMBINE_EXT ||
 161           ctx->Texture.Unit[i].EnvMode == GL_COMBINE4_NV) {
 162          swrast->_AnyTextureCombine = GL_TRUE;
 163          return;
 164       }
 165    }
 166 }
 167
 168
 169 #define _SWRAST_NEW_DERIVED (_SWRAST_NEW_RASTERMASK |   \
 170                              _NEW_TEXTURE |             \
 171                              _NEW_HINT |                \
 172                              _NEW_POLYGON )
 173
 174 /* State referenced by _swrast_choose_triangle, _swrast_choose_line.
 175  */
 176 #define _SWRAST_NEW_TRIANGLE (_SWRAST_NEW_DERIVED |             \
 177                               _NEW_RENDERMODE|                  \
 178                               _NEW_POLYGON|                     \
 179                               _NEW_DEPTH|                       \
 180                               _NEW_STENCIL|                     \
 181                               _NEW_COLOR|                       \
 182                               _NEW_TEXTURE|                     \
 183                               _SWRAST_NEW_RASTERMASK|           \
 184                               _NEW_LIGHT|                       \
 185                               _NEW_FOG |                        \
 186                               _DD_NEW_SEPARATE_SPECULAR)
 187
 188 #define _SWRAST_NEW_LINE (_SWRAST_NEW_DERIVED |         \
 189                           _NEW_RENDERMODE|              \
 190                           _NEW_LINE|                    \
 191                           _NEW_TEXTURE|                 \
 192                           _NEW_LIGHT|                   \
 193                           _NEW_FOG|                     \
 194                           _NEW_DEPTH |                  \
 195                           _DD_NEW_SEPARATE_SPECULAR)
 196
 197 #define _SWRAST_NEW_POINT (_SWRAST_NEW_DERIVED |        \
 198                            _NEW_RENDERMODE |            \
 199                            _NEW_POINT |                 \
 200                            _NEW_TEXTURE |               \
 201                            _NEW_LIGHT |                 \
 202                            _NEW_FOG |                   \
 203                            _DD_NEW_SEPARATE_SPECULAR)
 204
 205 #define _SWRAST_NEW_TEXTURE_SAMPLE_FUNC _NEW_TEXTURE
 206
 207 #define _SWRAST_NEW_TEXTURE_ENV_MODE _NEW_TEXTURE
 208
 209 #define _SWRAST_NEW_BLEND_FUNC _NEW_COLOR
 210
 211
 212
 213 /* Stub for swrast->Triangle to select a true triangle function
 214  * after a state change.
 215  */
 216 static void
 217 _swrast_validate_triangle( GLcontext *ctx,
 218                            const SWvertex *v0,
 219                            const SWvertex *v1,
 220                            const SWvertex *v2 )
 221 {
 222    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 223
 224    _swrast_validate_derived( ctx );
 225    swrast->choose_triangle( ctx );
 226
 227    if ((ctx->_TriangleCaps & DD_SEPARATE_SPECULAR) &&
 228        ctx->Texture._EnabledUnits == 0) {
 229       swrast->SpecTriangle = swrast->Triangle;
 230       swrast->Triangle = _swrast_add_spec_terms_triangle;
 231    }
 232
 233    swrast->Triangle( ctx, v0, v1, v2 );
 234 }
 235
 236 static void
 237 _swrast_validate_line( GLcontext *ctx, const SWvertex *v0, const SWvertex *v1 )
 238 {
 239    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 240
 241    _swrast_validate_derived( ctx );
 242    swrast->choose_line( ctx );
 243
 244    if ((ctx->_TriangleCaps & DD_SEPARATE_SPECULAR) &&
 245        ctx->Texture._EnabledUnits == 0) {
 246       swrast->SpecLine = swrast->Line;
 247       swrast->Line = _swrast_add_spec_terms_line;
 248    }
 249
 250
 251    swrast->Line( ctx, v0, v1 );
 252 }
 253
 254 static void
 255 _swrast_validate_point( GLcontext *ctx, const SWvertex *v0 )
 256 {
 257    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 258
 259    _swrast_validate_derived( ctx );
 260    swrast->choose_point( ctx );
 261
 262    if ((ctx->_TriangleCaps & DD_SEPARATE_SPECULAR) &&
 263        ctx->Texture._EnabledUnits == 0) {
 264       swrast->SpecPoint = swrast->Point;
 265       swrast->Point = _swrast_add_spec_terms_point;
 266    }
 267
 268    swrast->Point( ctx, v0 );
 269 }
 270
 271
 272 static void
 273 _swrast_validate_blend_func( GLcontext *ctx, GLuint n,
 274                              const GLubyte mask[],
 275                              GLchan src[][4],
 276                              CONST GLchan dst[][4] )
 277 {
 278    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 279
 280    _swrast_validate_derived( ctx );
 281    _swrast_choose_blend_func( ctx );
 282
 283    swrast->BlendFunc( ctx, n, mask, src, dst );
 284 }
 285
 286
 287 static void
 288 _swrast_validate_texture_sample( GLcontext *ctx, GLuint texUnit,
 289                                  const struct gl_texture_object *tObj,
 290                                  GLuint n, const GLfloat texcoords[][4],
 291                                  const GLfloat lambda[], GLchan rgba[][4] )
 292 {
 293    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 294
 295    _swrast_validate_derived( ctx );
 296
 297    /* Compute min/mag filter threshold */
 298    if (tObj->MinFilter != tObj->MagFilter) {
 299       if (tObj->MagFilter == GL_LINEAR
 300           && (tObj->MinFilter == GL_NEAREST_MIPMAP_NEAREST ||
 301               tObj->MinFilter == GL_NEAREST_MIPMAP_LINEAR)) {
 302          swrast->_MinMagThresh[texUnit] = 0.5F;
 303       }
 304       else {
 305          swrast->_MinMagThresh[texUnit] = 0.0F;
 306       }
 307    }
 308
 309    swrast->TextureSample[texUnit] =
 310       _swrast_choose_texture_sample_func( ctx, tObj );
 311
 312    swrast->TextureSample[texUnit]( ctx, texUnit, tObj, n, texcoords,
 313                                    lambda, rgba );
 314
 315    /* GL_SGI_texture_color_table */
 316    if (ctx->Texture.Unit[texUnit].ColorTableEnabled) {
 317       _swrast_texture_table_lookup(&ctx->Texture.Unit[texUnit].ColorTable, n, rgba);
 318    }
 319 }
 320
 321
 322 static void
 323 _swrast_sleep( GLcontext *ctx, GLuint new_state )
 324 {
 325 }
 326
 327
 328 static void
 329 _swrast_invalidate_state( GLcontext *ctx, GLuint new_state )
 330 {
 331    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 332    GLuint i;
 333
 334    swrast->NewState |= new_state;
 335
 336    /* After 10 statechanges without any swrast functions being called,
 337     * put the module to sleep.
 338     */
 339    if (++swrast->StateChanges > 10) {
 340       swrast->InvalidateState = _swrast_sleep;
 341       swrast->NewState = ~0;
 342       new_state = ~0;
 343    }
 344
 345    if (new_state & swrast->invalidate_triangle)
 346       swrast->Triangle = _swrast_validate_triangle;
 347
 348    if (new_state & swrast->invalidate_line)
 349       swrast->Line = _swrast_validate_line;
 350
 351    if (new_state & swrast->invalidate_point)
 352       swrast->Point = _swrast_validate_point;
 353
 354    if (new_state & _SWRAST_NEW_BLEND_FUNC)
 355       swrast->BlendFunc = _swrast_validate_blend_func;
 356
 357    if (new_state & _SWRAST_NEW_TEXTURE_SAMPLE_FUNC)
 358       for (i = 0 ; i < ctx->Const.MaxTextureUnits ; i++)
 359          swrast->TextureSample[i] = _swrast_validate_texture_sample;
 360
 361    if (ctx->Visual.rgbMode) {
 362       ASSERT(swrast->Driver.WriteRGBASpan);
 363       ASSERT(swrast->Driver.WriteRGBSpan);
 364       ASSERT(swrast->Driver.WriteMonoRGBASpan);
 365       ASSERT(swrast->Driver.WriteRGBAPixels);
 366       ASSERT(swrast->Driver.WriteMonoRGBAPixels);
 367       ASSERT(swrast->Driver.ReadRGBASpan);
 368       ASSERT(swrast->Driver.ReadRGBAPixels);
 369    }
 370    else {
 371       ASSERT(swrast->Driver.WriteCI32Span);
 372       ASSERT(swrast->Driver.WriteCI8Span);
 373       ASSERT(swrast->Driver.WriteMonoCISpan);
 374       ASSERT(swrast->Driver.WriteCI32Pixels);
 375       ASSERT(swrast->Driver.WriteMonoCIPixels);
 376       ASSERT(swrast->Driver.ReadCI32Span);
 377       ASSERT(swrast->Driver.ReadCI32Pixels);
 378    }
 379 }
 380
 381
 382 void
 383 _swrast_validate_derived( GLcontext *ctx )
 384 {
 385    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 386
 387    if (swrast->NewState) {
 388       if (swrast->NewState & _SWRAST_NEW_RASTERMASK)
 389          _swrast_update_rasterflags( ctx );
 390
 391       if (swrast->NewState & _NEW_POLYGON)
 392          _swrast_update_polygon( ctx );
 393
 394       if (swrast->NewState & _NEW_HINT)
 395          _swrast_update_hint( ctx );
 396
 397       if (swrast->NewState & _SWRAST_NEW_TEXTURE_ENV_MODE)
 398          _swrast_update_texture_env( ctx );
 399
 400       swrast->NewState = 0;
 401       swrast->StateChanges = 0;
 402       swrast->InvalidateState = _swrast_invalidate_state;
 403    }
 404 }
 405
 406 #define SWRAST_DEBUG 0
 407
 408 /* Public entrypoints:  See also s_accum.c, s_bitmap.c, etc.
 409  */
 410 void
 411 _swrast_Quad( GLcontext *ctx,
 412               const SWvertex *v0, const SWvertex *v1,
 413               const SWvertex *v2, const SWvertex *v3 )
 414 {
 415    if (SWRAST_DEBUG) {
 416       _mesa_debug(ctx, "_swrast_Quad\n");
 417       _swrast_print_vertex( ctx, v0 );
 418       _swrast_print_vertex( ctx, v1 );
 419       _swrast_print_vertex( ctx, v2 );
 420       _swrast_print_vertex( ctx, v3 );
 421    }
 422    SWRAST_CONTEXT(ctx)->Triangle( ctx, v0, v1, v3 );
 423    SWRAST_CONTEXT(ctx)->Triangle( ctx, v1, v2, v3 );
 424 }
 425
 426 void
 427 _swrast_Triangle( GLcontext *ctx, const SWvertex *v0,
 428                   const SWvertex *v1, const SWvertex *v2 )
 429 {
 430    if (SWRAST_DEBUG) {
 431       _mesa_debug(ctx, "_swrast_Triangle\n");
 432       _swrast_print_vertex( ctx, v0 );
 433       _swrast_print_vertex( ctx, v1 );
 434       _swrast_print_vertex( ctx, v2 );
 435    }
 436    SWRAST_CONTEXT(ctx)->Triangle( ctx, v0, v1, v2 );
 437 }
 438
 439 void
 440 _swrast_Line( GLcontext *ctx, const SWvertex *v0, const SWvertex *v1 )
 441 {
 442    if (SWRAST_DEBUG) {
 443       _mesa_debug(ctx, "_swrast_Line\n");
 444       _swrast_print_vertex( ctx, v0 );
 445       _swrast_print_vertex( ctx, v1 );
 446    }
 447    SWRAST_CONTEXT(ctx)->Line( ctx, v0, v1 );
 448 }
 449
 450 void
 451 _swrast_Point( GLcontext *ctx, const SWvertex *v0 )
 452 {
 453    if (SWRAST_DEBUG) {
 454       _mesa_debug(ctx, "_swrast_Point\n");
 455       _swrast_print_vertex( ctx, v0 );
 456    }
 457    SWRAST_CONTEXT(ctx)->Point( ctx, v0 );
 458 }
 459
 460 void
 461 _swrast_InvalidateState( GLcontext *ctx, GLuint new_state )
 462 {
 463    if (SWRAST_DEBUG) {
 464       _mesa_debug(ctx, "_swrast_InvalidateState\n");
 465    }
 466    SWRAST_CONTEXT(ctx)->InvalidateState( ctx, new_state );
 467 }
 468
 469 void
 470 _swrast_ResetLineStipple( GLcontext *ctx )
 471 {
 472    if (SWRAST_DEBUG) {
 473       _mesa_debug(ctx, "_swrast_ResetLineStipple\n");
 474    }
 475    SWRAST_CONTEXT(ctx)->StippleCounter = 0;
 476 }
 477
 478 void
 479 _swrast_allow_vertex_fog( GLcontext *ctx, GLboolean value )
 480 {
 481    if (SWRAST_DEBUG) {
 482       _mesa_debug(ctx, "_swrast_allow_vertex_fog %d\n", value);
 483    }
 484    SWRAST_CONTEXT(ctx)->InvalidateState( ctx, _NEW_HINT );
 485    SWRAST_CONTEXT(ctx)->AllowVertexFog = value;
 486 }
 487
 488 void
 489 _swrast_allow_pixel_fog( GLcontext *ctx, GLboolean value )
 490 {
 491    if (SWRAST_DEBUG) {
 492       _mesa_debug(ctx, "_swrast_allow_pixel_fog %d\n", value);
 493    }
 494    SWRAST_CONTEXT(ctx)->InvalidateState( ctx, _NEW_HINT );
 495    SWRAST_CONTEXT(ctx)->AllowPixelFog = value;
 496 }
 497
 498
 499 GLboolean
 500 _swrast_CreateContext( GLcontext *ctx )
 501 {
 502    GLuint i;
 503    SWcontext *swrast = (SWcontext *)CALLOC(sizeof(SWcontext));
 504
 505    if (SWRAST_DEBUG) {
 506       _mesa_debug(ctx, "_swrast_CreateContext\n");
 507    }
 508
 509    if (!swrast)
 510       return GL_FALSE;
 511
 512    swrast->NewState = ~0;
 513
 514    swrast->choose_point = _swrast_choose_point;
 515    swrast->choose_line = _swrast_choose_line;
 516    swrast->choose_triangle = _swrast_choose_triangle;
 517
 518    swrast->invalidate_point = _SWRAST_NEW_POINT;
 519    swrast->invalidate_line = _SWRAST_NEW_LINE;
 520    swrast->invalidate_triangle = _SWRAST_NEW_TRIANGLE;
 521
 522    swrast->Point = _swrast_validate_point;
 523    swrast->Line = _swrast_validate_line;
 524    swrast->Triangle = _swrast_validate_triangle;
 525    swrast->InvalidateState = _swrast_sleep;
 526    swrast->BlendFunc = _swrast_validate_blend_func;
 527
 528    swrast->AllowVertexFog = GL_TRUE;
 529    swrast->AllowPixelFog = GL_TRUE;
 530
 531    if (ctx->Visual.doubleBufferMode)
 532       swrast->CurrentBuffer = BACK_LEFT_BIT;
 533    else
 534       swrast->CurrentBuffer = FRONT_LEFT_BIT;
 535
 536    /* Optimized Accum buffer */
 537    swrast->_IntegerAccumMode = GL_TRUE;
 538    swrast->_IntegerAccumScaler = 0.0;
 539
 540    for (i = 0; i < MAX_TEXTURE_IMAGE_UNITS; i++)
 541       swrast->TextureSample[i] = _swrast_validate_texture_sample;
 542
 543    swrast->SpanArrays = MALLOC_STRUCT(span_arrays);
 544    if (!swrast->SpanArrays) {
 545       FREE(swrast);
 546       return GL_FALSE;
 547    }
 548
 549    /* init point span buffer */
 550    swrast->PointSpan.primitive = GL_POINT;
 551    swrast->PointSpan.start = 0;
 552    swrast->PointSpan.end = 0;
 553    swrast->PointSpan.facing = 0;
 554    swrast->PointSpan.array = swrast->SpanArrays;
 555
 556    assert(ctx->Const.MaxTextureUnits > 0);
 557    assert(ctx->Const.MaxTextureUnits <= MAX_TEXTURE_UNITS);
 558
 559    swrast->TexelBuffer = (GLchan *) MALLOC(ctx->Const.MaxTextureUnits *
 560                                            MAX_WIDTH * 4 * sizeof(GLchan));
 561    if (!swrast->TexelBuffer) {
 562       FREE(swrast->SpanArrays);
 563       FREE(swrast);
 564       return GL_FALSE;
 565    }
 566
 567    ctx->swrast_context = swrast;
 568
 569    return GL_TRUE;
 570 }
 571
 572 void
 573 _swrast_DestroyContext( GLcontext *ctx )
 574 {
 575    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 576
 577    if (SWRAST_DEBUG) {
 578       _mesa_debug(ctx, "_swrast_DestroyContext\n");
 579    }
 580
 581    FREE( swrast->SpanArrays );
 582    FREE( swrast->TexelBuffer );
 583    FREE( swrast );
 584
 585    ctx->swrast_context = 0;
 586 }
 587
 588
 589 struct swrast_device_driver *
 590 _swrast_GetDeviceDriverReference( GLcontext *ctx )
 591 {
 592    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 593    return &swrast->Driver;
 594 }
 595
 596 void
 597 _swrast_flush( GLcontext *ctx )
 598 {
 599    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 600    /* flush any pending fragments from rendering points */
 601    if (swrast->PointSpan.end > 0) {
 602       if (ctx->Visual.rgbMode) {
 603          if (ctx->Texture._EnabledUnits)
 604             _mesa_write_texture_span(ctx, &(swrast->PointSpan));
 605          else
 606             _mesa_write_rgba_span(ctx, &(swrast->PointSpan));
 607       }
 608       else {
 609          _mesa_write_index_span(ctx, &(swrast->PointSpan));
 610       }
 611       swrast->PointSpan.end = 0;
 612    }
 613 }
 614
 615 void
 616 _swrast_render_primitive( GLcontext *ctx, GLenum prim )
 617 {
 618    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 619    if (swrast->Primitive == GL_POINTS && prim != GL_POINTS) {
 620       _swrast_flush(ctx);
 621    }
 622    swrast->Primitive = prim;
 623 }
 624
 625
 626 void
 627 _swrast_render_start( GLcontext *ctx )
 628 {
 629    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 630    if (swrast->Driver.SpanRenderStart)
 631       swrast->Driver.SpanRenderStart( ctx );
 632    swrast->PointSpan.end = 0;
 633 }
 634
 635 void
 636 _swrast_render_finish( GLcontext *ctx )
 637 {
 638    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 639    if (swrast->Driver.SpanRenderFinish)
 640       swrast->Driver.SpanRenderFinish( ctx );
 641
 642    _swrast_flush(ctx);
 643 }
 644
 645
 646 #define SWRAST_DEBUG_VERTICES 0
 647
 648 void
 649 _swrast_print_vertex( GLcontext *ctx, const SWvertex *v )
 650 {
 651    GLuint i;
 652
 653    if (SWRAST_DEBUG_VERTICES) {
 654       _mesa_debug(ctx, "win %f %f %f %f\n",
 655                   v->win[0], v->win[1], v->win[2], v->win[3]);
 656
 657       for (i = 0 ; i < ctx->Const.MaxTextureUnits ; i++)
 658          if (ctx->Texture.Unit[i]._ReallyEnabled)
 659             _mesa_debug(ctx, "texcoord[%d] %f %f %f %f\n", i,
 660                         v->texcoord[i][0], v->texcoord[i][1],
 661                         v->texcoord[i][2], v->texcoord[i][3]);
 662
 663 #if CHAN_TYPE == GL_FLOAT
 664       _mesa_debug(ctx, "color %f %f %f %f\n",
 665                   v->color[0], v->color[1], v->color[2], v->color[3]);
 666       _mesa_debug(ctx, "spec %f %f %f %f\n",
 667                   v->specular[0], v->specular[1],
 668                   v->specular[2], v->specular[3]);
 669 #else
 670       _mesa_debug(ctx, "color %d %d %d %d\n",
 671                   v->color[0], v->color[1], v->color[2], v->color[3]);
 672       _mesa_debug(ctx, "spec %d %d %d %d\n",
 673                   v->specular[0], v->specular[1],
 674                   v->specular[2], v->specular[3]);
 675 #endif
 676       _mesa_debug(ctx, "fog %f\n", v->fog);
 677       _mesa_debug(ctx, "index %d\n", v->index);
 678       _mesa_debug(ctx, "pointsize %f\n", v->pointSize);
 679       _mesa_debug(ctx, "\n");
 680    }
 681 }