src/mesa/swrast/s_context.c

   1 /*
   2  * Mesa 3-D graphics library
   3  * Version:  6.5.3
   4  *
   5  * Copyright (C) 1999-2007  Brian Paul   All Rights Reserved.
   6  *
   7  * Permission is hereby granted, free of charge, to any person obtaining a
   8  * copy of this software and associated documentation files (the "Software"),
   9  * to deal in the Software without restriction, including without limitation
  10  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  11  * and/or sell copies of the Software, and to permit persons to whom the
  12  * Software is furnished to do so, subject to the following conditions:
  13  *
  14  * The above copyright notice and this permission notice shall be included
  15  * in all copies or substantial portions of the Software.
  16  *
  17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  18  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  20  * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
  21  * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  22  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  23  *
  24  * Authors:
  25  *    Keith Whitwell <keith@tungstengraphics.com>
  26  *    Brian Paul
  27  */
  28
  29 #include "imports.h"
  30 #include "bufferobj.h"
  31 #include "context.h"
  32 #include "colormac.h"
  33 #include "mtypes.h"
  34 #include "prog_statevars.h"
  35 #include "teximage.h"
  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_texfilter.h"
  44
  45
  46 /**
  47  * Recompute the value of swrast->_RasterMask, etc. according to
  48  * the current context.  The _RasterMask field can be easily tested by
  49  * drivers to determine certain basic GL state (does the primitive need
  50  * stenciling, logic-op, fog, etc?).
  51  */
  52 static void
  53 _swrast_update_rasterflags( GLcontext *ctx )
  54 {
  55    SWcontext *swrast = SWRAST_CONTEXT(ctx);
  56    GLbitfield rasterMask = 0;
  57
  58    if (ctx->Color.AlphaEnabled)           rasterMask |= ALPHATEST_BIT;
  59    if (ctx->Color.BlendEnabled)           rasterMask |= BLEND_BIT;
  60    if (ctx->Depth.Test)                   rasterMask |= DEPTH_BIT;
  61    if (swrast->_FogEnabled)               rasterMask |= FOG_BIT;
  62    if (ctx->Scissor.Enabled)              rasterMask |= CLIP_BIT;
  63    if (ctx->Stencil.Enabled)              rasterMask |= STENCIL_BIT;
  64    if (ctx->Visual.rgbMode) {
  65       const GLuint colorMask = *((GLuint *) &ctx->Color.ColorMask);
  66       if (colorMask != 0xffffffff)        rasterMask |= MASKING_BIT;
  67       if (ctx->Color._LogicOpEnabled)     rasterMask |= LOGIC_OP_BIT;
  68       if (ctx->Texture._EnabledUnits)     rasterMask |= TEXTURE_BIT;
  69    }
  70    else {
  71       if (ctx->Color.IndexMask != 0xffffffff) rasterMask |= MASKING_BIT;
  72       if (ctx->Color.IndexLogicOpEnabled)     rasterMask |= LOGIC_OP_BIT;
  73    }
  74
  75    if (   ctx->Viewport.X < 0
  76        || ctx->Viewport.X + ctx->Viewport.Width > (GLint) ctx->DrawBuffer->Width
  77        || ctx->Viewport.Y < 0
  78        || ctx->Viewport.Y + ctx->Viewport.Height > (GLint) ctx->DrawBuffer->Height) {
  79       rasterMask |= CLIP_BIT;
  80    }
  81
  82    if (ctx->Query.CurrentOcclusionObject)
  83       rasterMask |= OCCLUSION_BIT;
  84
  85
  86    /* If we're not drawing to exactly one color buffer set the
  87     * MULTI_DRAW_BIT flag.  Also set it if we're drawing to no
  88     * buffers or the RGBA or CI mask disables all writes.
  89     */
  90    if (ctx->DrawBuffer->_NumColorDrawBuffers[0] != 1) {
  91       /* more than one color buffer designated for writing (or zero buffers) */
  92       rasterMask |= MULTI_DRAW_BIT;
  93    }
  94    else if (ctx->Visual.rgbMode && *((GLuint *) ctx->Color.ColorMask) == 0) {
  95       rasterMask |= MULTI_DRAW_BIT; /* all RGBA channels disabled */
  96    }
  97    else if (!ctx->Visual.rgbMode && ctx->Color.IndexMask==0) {
  98       rasterMask |= MULTI_DRAW_BIT; /* all color index bits disabled */
  99    }
 100
 101    if (ctx->FragmentProgram._Current) {
 102       rasterMask |= FRAGPROG_BIT;
 103    }
 104
 105    if (ctx->ATIFragmentShader._Enabled) {
 106       rasterMask |= ATIFRAGSHADER_BIT;
 107    }
 108
 109 #if CHAN_TYPE == GL_FLOAT
 110    if (ctx->Color.ClampFragmentColor == GL_TRUE) {
 111       rasterMask |= CLAMPING_BIT;
 112    }
 113 #endif
 114
 115    SWRAST_CONTEXT(ctx)->_RasterMask = rasterMask;
 116 }
 117
 118
 119 /**
 120  * Examine polycon culls tate to compute the _BackfaceSign field.
 121  * _BackfaceSign will be 0 if no culling, -1 if culling back-faces,
 122  * and 1 if culling front-faces.  The Polygon FrontFace state also
 123  * factors in.
 124  */
 125 static void
 126 _swrast_update_polygon( GLcontext *ctx )
 127 {
 128    GLfloat backface_sign;
 129
 130    if (ctx->Polygon.CullFlag) {
 131       backface_sign = 1.0;
 132       switch (ctx->Polygon.CullFaceMode) {
 133       case GL_BACK:
 134          if (ctx->Polygon.FrontFace == GL_CCW)
 135             backface_sign = -1.0;
 136          break;
 137       case GL_FRONT:
 138          if (ctx->Polygon.FrontFace != GL_CCW)
 139             backface_sign = -1.0;
 140          break;
 141       case GL_FRONT_AND_BACK:
 142          /* fallthrough */
 143       default:
 144          backface_sign = 0.0;
 145          break;
 146       }
 147    }
 148    else {
 149       backface_sign = 0.0;
 150    }
 151
 152    SWRAST_CONTEXT(ctx)->_BackfaceSign = backface_sign;
 153 }
 154
 155
 156 /**
 157  * Update the _PreferPixelFog field to indicate if we need to compute
 158  * fog factors per-fragment.
 159  */
 160 static void
 161 _swrast_update_fog_hint( GLcontext *ctx )
 162 {
 163    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 164    swrast->_PreferPixelFog = (!swrast->AllowVertexFog ||
 165                               ctx->FragmentProgram._Current ||
 166                               (ctx->Hint.Fog == GL_NICEST &&
 167                                swrast->AllowPixelFog));
 168 }
 169
 170
 171
 172 /**
 173  * Update the swrast->_AnyTextureCombine flag.
 174  */
 175 static void
 176 _swrast_update_texture_env( GLcontext *ctx )
 177 {
 178    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 179    GLuint i;
 180    swrast->_AnyTextureCombine = GL_FALSE;
 181    for (i = 0; i < ctx->Const.MaxTextureUnits; i++) {
 182       if (ctx->Texture.Unit[i].EnvMode == GL_COMBINE_EXT ||
 183           ctx->Texture.Unit[i].EnvMode == GL_COMBINE4_NV) {
 184          swrast->_AnyTextureCombine = GL_TRUE;
 185          return;
 186       }
 187    }
 188 }
 189
 190
 191 /**
 192  * Update swrast->_FogColor and swrast->_FogEnable values.
 193  */
 194 static void
 195 _swrast_update_fog_state( GLcontext *ctx )
 196 {
 197    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 198    const struct gl_fragment_program *fp = ctx->FragmentProgram._Current;
 199
 200    /* determine if fog is needed, and if so, which fog mode */
 201    swrast->_FogEnabled = GL_FALSE;
 202    if (fp && fp->Base.Target == GL_FRAGMENT_PROGRAM_ARB) {
 203       if (fp->FogOption != GL_NONE) {
 204          swrast->_FogEnabled = GL_TRUE;
 205          swrast->_FogMode = fp->FogOption;
 206       }
 207    }
 208    else if (ctx->Fog.Enabled) {
 209       swrast->_FogEnabled = GL_TRUE;
 210       swrast->_FogMode = ctx->Fog.Mode;
 211    }
 212 }
 213
 214
 215 /**
 216  * Update state for running fragment programs.  Basically, load the
 217  * program parameters with current state values.
 218  */
 219 static void
 220 _swrast_update_fragment_program(GLcontext *ctx, GLbitfield newState)
 221 {
 222    const struct gl_fragment_program *fp = ctx->FragmentProgram._Current;
 223    if (fp) {
 224 #if 0
 225       /* XXX Need a way to trigger the initial loading of parameters
 226        * even when there's no recent state changes.
 227        */
 228       if (fp->Base.Parameters->StateFlags & newState)
 229 #endif
 230          _mesa_load_state_parameters(ctx, fp->Base.Parameters);
 231    }
 232 }
 233
 234
 235
 236 #define _SWRAST_NEW_DERIVED (_SWRAST_NEW_RASTERMASK |   \
 237                              _NEW_TEXTURE |             \
 238                              _NEW_HINT |                \
 239                              _NEW_POLYGON )
 240
 241 /* State referenced by _swrast_choose_triangle, _swrast_choose_line.
 242  */
 243 #define _SWRAST_NEW_TRIANGLE (_SWRAST_NEW_DERIVED |             \
 244                               _NEW_RENDERMODE|                  \
 245                               _NEW_POLYGON|                     \
 246                               _NEW_DEPTH|                       \
 247                               _NEW_STENCIL|                     \
 248                               _NEW_COLOR|                       \
 249                               _NEW_TEXTURE|                     \
 250                               _SWRAST_NEW_RASTERMASK|           \
 251                               _NEW_LIGHT|                       \
 252                               _NEW_FOG |                        \
 253                               _DD_NEW_SEPARATE_SPECULAR)
 254
 255 #define _SWRAST_NEW_LINE (_SWRAST_NEW_DERIVED |         \
 256                           _NEW_RENDERMODE|              \
 257                           _NEW_LINE|                    \
 258                           _NEW_TEXTURE|                 \
 259                           _NEW_LIGHT|                   \
 260                           _NEW_FOG|                     \
 261                           _NEW_DEPTH |                  \
 262                           _DD_NEW_SEPARATE_SPECULAR)
 263
 264 #define _SWRAST_NEW_POINT (_SWRAST_NEW_DERIVED |        \
 265                            _NEW_RENDERMODE |            \
 266                            _NEW_POINT |                 \
 267                            _NEW_TEXTURE |               \
 268                            _NEW_LIGHT |                 \
 269                            _NEW_FOG |                   \
 270                            _DD_NEW_SEPARATE_SPECULAR)
 271
 272 #define _SWRAST_NEW_TEXTURE_SAMPLE_FUNC _NEW_TEXTURE
 273
 274 #define _SWRAST_NEW_TEXTURE_ENV_MODE _NEW_TEXTURE
 275
 276 #define _SWRAST_NEW_BLEND_FUNC _NEW_COLOR
 277
 278
 279
 280 /**
 281  * Stub for swrast->Triangle to select a true triangle function
 282  * after a state change.
 283  */
 284 static void
 285 _swrast_validate_triangle( GLcontext *ctx,
 286                            const SWvertex *v0,
 287                            const SWvertex *v1,
 288                            const SWvertex *v2 )
 289 {
 290    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 291
 292    _swrast_validate_derived( ctx );
 293    swrast->choose_triangle( ctx );
 294    ASSERT(swrast->Triangle);
 295
 296    if (ctx->Texture._EnabledUnits == 0
 297        && NEED_SECONDARY_COLOR(ctx)
 298        && !ctx->FragmentProgram._Current) {
 299       /* separate specular color, but no texture */
 300       swrast->SpecTriangle = swrast->Triangle;
 301       swrast->Triangle = _swrast_add_spec_terms_triangle;
 302    }
 303
 304    swrast->Triangle( ctx, v0, v1, v2 );
 305 }
 306
 307 /**
 308  * Called via swrast->Line.  Examine current GL state and choose a software
 309  * line routine.  Then call it.
 310  */
 311 static void
 312 _swrast_validate_line( GLcontext *ctx, const SWvertex *v0, const SWvertex *v1 )
 313 {
 314    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 315
 316    _swrast_validate_derived( ctx );
 317    swrast->choose_line( ctx );
 318    ASSERT(swrast->Line);
 319
 320    if (ctx->Texture._EnabledUnits == 0
 321        && NEED_SECONDARY_COLOR(ctx)
 322        && !ctx->FragmentProgram._Current) {
 323       swrast->SpecLine = swrast->Line;
 324       swrast->Line = _swrast_add_spec_terms_line;
 325    }
 326
 327
 328    swrast->Line( ctx, v0, v1 );
 329 }
 330
 331 /**
 332  * Called via swrast->Point.  Examine current GL state and choose a software
 333  * point routine.  Then call it.
 334  */
 335 static void
 336 _swrast_validate_point( GLcontext *ctx, const SWvertex *v0 )
 337 {
 338    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 339
 340    _swrast_validate_derived( ctx );
 341    swrast->choose_point( ctx );
 342
 343    if (ctx->Texture._EnabledUnits == 0
 344        && NEED_SECONDARY_COLOR(ctx)
 345        && !ctx->FragmentProgram._Current) {
 346       swrast->SpecPoint = swrast->Point;
 347       swrast->Point = _swrast_add_spec_terms_point;
 348    }
 349
 350    swrast->Point( ctx, v0 );
 351 }
 352
 353
 354 /**
 355  * Called via swrast->BlendFunc.  Examine GL state to choose a blending
 356  * function, then call it.
 357  */
 358 static void _ASMAPI
 359 _swrast_validate_blend_func(GLcontext *ctx, GLuint n, const GLubyte mask[],
 360                             GLvoid *src, const GLvoid *dst,
 361                             GLenum chanType )
 362 {
 363    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 364
 365    _swrast_validate_derived( ctx ); /* why is this needed? */
 366    _swrast_choose_blend_func( ctx, chanType );
 367
 368    swrast->BlendFunc( ctx, n, mask, src, dst, chanType );
 369 }
 370
 371
 372 /**
 373  * Make sure we have texture image data for all the textures we may need
 374  * for subsequent rendering.
 375  */
 376 static void
 377 _swrast_validate_texture_images(GLcontext *ctx)
 378 {
 379    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 380    GLuint u;
 381
 382    if (!swrast->ValidateTextureImage || !ctx->Texture._EnabledUnits) {
 383       /* no textures enabled, or no way to validate images! */
 384       return;
 385    }
 386
 387    for (u = 0; u < ctx->Const.MaxTextureImageUnits; u++) {
 388       if (ctx->Texture.Unit[u]._ReallyEnabled) {
 389          struct gl_texture_object *texObj = ctx->Texture.Unit[u]._Current;
 390          ASSERT(texObj);
 391          if (texObj) {
 392             GLuint numFaces = (texObj->Target == GL_TEXTURE_CUBE_MAP) ? 6 : 1;
 393             GLuint face;
 394             for (face = 0; face < numFaces; face++) {
 395                GLint lvl;
 396                for (lvl = texObj->BaseLevel; lvl <= texObj->_MaxLevel; lvl++) {
 397                   struct gl_texture_image *texImg = texObj->Image[face][lvl];
 398                   if (texImg && !texImg->Data) {
 399                      swrast->ValidateTextureImage(ctx, texObj, face, lvl);
 400                      ASSERT(texObj->Image[face][lvl]->Data);
 401                   }
 402                }
 403             }
 404          }
 405       }
 406    }
 407 }
 408
 409
 410 /**
 411  * Free the texture image data attached to all currently enabled
 412  * textures.  Meant to be called by device drivers when transitioning
 413  * from software to hardware rendering.
 414  */
 415 void
 416 _swrast_eject_texture_images(GLcontext *ctx)
 417 {
 418    GLuint u;
 419
 420    if (!ctx->Texture._EnabledUnits) {
 421       /* no textures enabled */
 422       return;
 423    }
 424
 425    for (u = 0; u < ctx->Const.MaxTextureImageUnits; u++) {
 426       if (ctx->Texture.Unit[u]._ReallyEnabled) {
 427          struct gl_texture_object *texObj = ctx->Texture.Unit[u]._Current;
 428          ASSERT(texObj);
 429          if (texObj) {
 430             GLuint numFaces = (texObj->Target == GL_TEXTURE_CUBE_MAP) ? 6 : 1;
 431             GLuint face;
 432             for (face = 0; face < numFaces; face++) {
 433                GLint lvl;
 434                for (lvl = texObj->BaseLevel; lvl <= texObj->_MaxLevel; lvl++) {
 435                   struct gl_texture_image *texImg = texObj->Image[face][lvl];
 436                   if (texImg && texImg->Data) {
 437                      _mesa_free_texmemory(texImg->Data);
 438                      texImg->Data = NULL;
 439                   }
 440                }
 441             }
 442          }
 443       }
 444    }
 445 }
 446
 447
 448
 449 static void
 450 _swrast_sleep( GLcontext *ctx, GLbitfield new_state )
 451 {
 452    (void) ctx; (void) new_state;
 453 }
 454
 455
 456 static void
 457 _swrast_invalidate_state( GLcontext *ctx, GLbitfield new_state )
 458 {
 459    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 460    GLuint i;
 461
 462    swrast->NewState |= new_state;
 463
 464    /* After 10 statechanges without any swrast functions being called,
 465     * put the module to sleep.
 466     */
 467    if (++swrast->StateChanges > 10) {
 468       swrast->InvalidateState = _swrast_sleep;
 469       swrast->NewState = ~0;
 470       new_state = ~0;
 471    }
 472
 473    if (new_state & swrast->InvalidateTriangleMask)
 474       swrast->Triangle = _swrast_validate_triangle;
 475
 476    if (new_state & swrast->InvalidateLineMask)
 477       swrast->Line = _swrast_validate_line;
 478
 479    if (new_state & swrast->InvalidatePointMask)
 480       swrast->Point = _swrast_validate_point;
 481
 482    if (new_state & _SWRAST_NEW_BLEND_FUNC)
 483       swrast->BlendFunc = _swrast_validate_blend_func;
 484
 485    if (new_state & _SWRAST_NEW_TEXTURE_SAMPLE_FUNC)
 486       for (i = 0 ; i < ctx->Const.MaxTextureImageUnits ; i++)
 487          swrast->TextureSample[i] = NULL;
 488 }
 489
 490
 491 static void
 492 _swrast_update_texture_samplers(GLcontext *ctx)
 493 {
 494    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 495    GLuint u;
 496
 497    for (u = 0; u < ctx->Const.MaxTextureImageUnits; u++) {
 498       const struct gl_texture_object *tObj = ctx->Texture.Unit[u]._Current;
 499       /* Note: If tObj is NULL, the sample function will be a simple
 500        * function that just returns opaque black (0,0,0,1).
 501        */
 502       swrast->TextureSample[u] = _swrast_choose_texture_sample_func(ctx, tObj);
 503    }
 504 }
 505
 506
 507 /**
 508  * Update the swrast->_FragmentAttribs field.
 509  */
 510 static void
 511 _swrast_update_fragment_attribs(GLcontext *ctx)
 512 {
 513    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 514
 515    if (ctx->FragmentProgram._Current) {
 516       swrast->_FragmentAttribs
 517          = ctx->FragmentProgram._Current->Base.InputsRead;
 518    }
 519    else {
 520       GLuint u;
 521       swrast->_FragmentAttribs = 0x0;
 522
 523       if (ctx->Depth.Test)
 524          swrast->_FragmentAttribs |= FRAG_BIT_WPOS;
 525       if (NEED_SECONDARY_COLOR(ctx))
 526          swrast->_FragmentAttribs |= FRAG_BIT_COL1;
 527       if (swrast->_FogEnabled)
 528          swrast->_FragmentAttribs |= FRAG_BIT_FOGC;
 529
 530       for (u = 0; u < ctx->Const.MaxTextureUnits; u++) {
 531          if (ctx->Texture.Unit[u]._ReallyEnabled) {
 532             swrast->_FragmentAttribs |= FRAG_BIT_TEX(u);
 533          }
 534       }
 535    }
 536
 537    /* Find lowest, highest bit set in _FragmentAttribs */
 538    {
 539       GLuint bits = swrast->_FragmentAttribs;
 540       GLuint i = 0;;
 541       while (bits) {
 542          i++;
 543          bits = bits >> 1;
 544       }
 545       swrast->_MaxFragmentAttrib = i;
 546       swrast->_MinFragmentAttrib = FRAG_ATTRIB_TEX0; /* XXX temporary */
 547    }
 548 }
 549
 550
 551 void
 552 _swrast_validate_derived( GLcontext *ctx )
 553 {
 554    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 555
 556    if (swrast->NewState) {
 557       if (swrast->NewState & _NEW_POLYGON)
 558          _swrast_update_polygon( ctx );
 559
 560       if (swrast->NewState & (_NEW_HINT | _NEW_PROGRAM))
 561          _swrast_update_fog_hint( ctx );
 562
 563       if (swrast->NewState & _SWRAST_NEW_TEXTURE_ENV_MODE)
 564          _swrast_update_texture_env( ctx );
 565
 566       if (swrast->NewState & (_NEW_FOG | _NEW_PROGRAM))
 567          _swrast_update_fog_state( ctx );
 568
 569       if (swrast->NewState & (_NEW_MODELVIEW |
 570                               _NEW_PROJECTION |
 571                               _NEW_TEXTURE_MATRIX |
 572                               _NEW_FOG |
 573                               _NEW_LIGHT |
 574                               _NEW_LINE |
 575                               _NEW_TEXTURE |
 576                               _NEW_TRANSFORM |
 577                               _NEW_POINT |
 578                               _NEW_VIEWPORT |
 579                               _NEW_PROGRAM))
 580          _swrast_update_fragment_program( ctx, swrast->NewState );
 581
 582       if (swrast->NewState & _NEW_TEXTURE)
 583          _swrast_update_texture_samplers( ctx );
 584
 585       if (swrast->NewState & (_NEW_TEXTURE | _NEW_PROGRAM))
 586          _swrast_validate_texture_images( ctx );
 587
 588       if (swrast->NewState & _SWRAST_NEW_RASTERMASK)
 589          _swrast_update_rasterflags( ctx );
 590
 591       if (swrast->NewState & (_NEW_DEPTH |
 592                               _NEW_FOG |
 593                               _NEW_PROGRAM |
 594                               _NEW_TEXTURE))
 595          _swrast_update_fragment_attribs(ctx);
 596
 597       swrast->NewState = 0;
 598       swrast->StateChanges = 0;
 599       swrast->InvalidateState = _swrast_invalidate_state;
 600    }
 601 }
 602
 603 #define SWRAST_DEBUG 0
 604
 605 /* Public entrypoints:  See also s_accum.c, s_bitmap.c, etc.
 606  */
 607 void
 608 _swrast_Quad( GLcontext *ctx,
 609               const SWvertex *v0, const SWvertex *v1,
 610               const SWvertex *v2, const SWvertex *v3 )
 611 {
 612    if (SWRAST_DEBUG) {
 613       _mesa_debug(ctx, "_swrast_Quad\n");
 614       _swrast_print_vertex( ctx, v0 );
 615       _swrast_print_vertex( ctx, v1 );
 616       _swrast_print_vertex( ctx, v2 );
 617       _swrast_print_vertex( ctx, v3 );
 618    }
 619    SWRAST_CONTEXT(ctx)->Triangle( ctx, v0, v1, v3 );
 620    SWRAST_CONTEXT(ctx)->Triangle( ctx, v1, v2, v3 );
 621 }
 622
 623 void
 624 _swrast_Triangle( GLcontext *ctx, const SWvertex *v0,
 625                   const SWvertex *v1, const SWvertex *v2 )
 626 {
 627    if (SWRAST_DEBUG) {
 628       _mesa_debug(ctx, "_swrast_Triangle\n");
 629       _swrast_print_vertex( ctx, v0 );
 630       _swrast_print_vertex( ctx, v1 );
 631       _swrast_print_vertex( ctx, v2 );
 632    }
 633    SWRAST_CONTEXT(ctx)->Triangle( ctx, v0, v1, v2 );
 634 }
 635
 636 void
 637 _swrast_Line( GLcontext *ctx, const SWvertex *v0, const SWvertex *v1 )
 638 {
 639    if (SWRAST_DEBUG) {
 640       _mesa_debug(ctx, "_swrast_Line\n");
 641       _swrast_print_vertex( ctx, v0 );
 642       _swrast_print_vertex( ctx, v1 );
 643    }
 644    SWRAST_CONTEXT(ctx)->Line( ctx, v0, v1 );
 645 }
 646
 647 void
 648 _swrast_Point( GLcontext *ctx, const SWvertex *v0 )
 649 {
 650    if (SWRAST_DEBUG) {
 651       _mesa_debug(ctx, "_swrast_Point\n");
 652       _swrast_print_vertex( ctx, v0 );
 653    }
 654    SWRAST_CONTEXT(ctx)->Point( ctx, v0 );
 655 }
 656
 657 void
 658 _swrast_InvalidateState( GLcontext *ctx, GLbitfield new_state )
 659 {
 660    if (SWRAST_DEBUG) {
 661       _mesa_debug(ctx, "_swrast_InvalidateState\n");
 662    }
 663    SWRAST_CONTEXT(ctx)->InvalidateState( ctx, new_state );
 664 }
 665
 666 void
 667 _swrast_ResetLineStipple( GLcontext *ctx )
 668 {
 669    if (SWRAST_DEBUG) {
 670       _mesa_debug(ctx, "_swrast_ResetLineStipple\n");
 671    }
 672    SWRAST_CONTEXT(ctx)->StippleCounter = 0;
 673 }
 674
 675 void
 676 _swrast_allow_vertex_fog( GLcontext *ctx, GLboolean value )
 677 {
 678    if (SWRAST_DEBUG) {
 679       _mesa_debug(ctx, "_swrast_allow_vertex_fog %d\n", value);
 680    }
 681    SWRAST_CONTEXT(ctx)->InvalidateState( ctx, _NEW_HINT );
 682    SWRAST_CONTEXT(ctx)->AllowVertexFog = value;
 683 }
 684
 685 void
 686 _swrast_allow_pixel_fog( GLcontext *ctx, GLboolean value )
 687 {
 688    if (SWRAST_DEBUG) {
 689       _mesa_debug(ctx, "_swrast_allow_pixel_fog %d\n", value);
 690    }
 691    SWRAST_CONTEXT(ctx)->InvalidateState( ctx, _NEW_HINT );
 692    SWRAST_CONTEXT(ctx)->AllowPixelFog = value;
 693 }
 694
 695
 696 GLboolean
 697 _swrast_CreateContext( GLcontext *ctx )
 698 {
 699    GLuint i;
 700    SWcontext *swrast = (SWcontext *)CALLOC(sizeof(SWcontext));
 701
 702    if (SWRAST_DEBUG) {
 703       _mesa_debug(ctx, "_swrast_CreateContext\n");
 704    }
 705
 706    if (!swrast)
 707       return GL_FALSE;
 708
 709    swrast->NewState = ~0;
 710
 711    swrast->choose_point = _swrast_choose_point;
 712    swrast->choose_line = _swrast_choose_line;
 713    swrast->choose_triangle = _swrast_choose_triangle;
 714
 715    swrast->InvalidatePointMask = _SWRAST_NEW_POINT;
 716    swrast->InvalidateLineMask = _SWRAST_NEW_LINE;
 717    swrast->InvalidateTriangleMask = _SWRAST_NEW_TRIANGLE;
 718
 719    swrast->Point = _swrast_validate_point;
 720    swrast->Line = _swrast_validate_line;
 721    swrast->Triangle = _swrast_validate_triangle;
 722    swrast->InvalidateState = _swrast_sleep;
 723    swrast->BlendFunc = _swrast_validate_blend_func;
 724
 725    swrast->AllowVertexFog = GL_TRUE;
 726    swrast->AllowPixelFog = GL_TRUE;
 727
 728    /* Optimized Accum buffer */
 729    swrast->_IntegerAccumMode = GL_FALSE;
 730    swrast->_IntegerAccumScaler = 0.0;
 731
 732    for (i = 0; i < MAX_TEXTURE_IMAGE_UNITS; i++)
 733       swrast->TextureSample[i] = NULL;
 734
 735    swrast->SpanArrays = MALLOC_STRUCT(sw_span_arrays);
 736    if (!swrast->SpanArrays) {
 737       FREE(swrast);
 738       return GL_FALSE;
 739    }
 740    swrast->SpanArrays->ChanType = CHAN_TYPE;
 741 #if CHAN_TYPE == GL_UNSIGNED_BYTE
 742    swrast->SpanArrays->rgba = swrast->SpanArrays->color.sz1.rgba;
 743    swrast->SpanArrays->spec = swrast->SpanArrays->color.sz1.spec;
 744 #elif CHAN_TYPE == GL_UNSIGNED_SHORT
 745    swrast->SpanArrays->rgba = swrast->SpanArrays->color.sz2.rgba;
 746    swrast->SpanArrays->spec = swrast->SpanArrays->color.sz2.spec;
 747 #else
 748    swrast->SpanArrays->rgba = swrast->SpanArrays->color.sz4.rgba;
 749    swrast->SpanArrays->spec = swrast->SpanArrays->color.sz4.spec;
 750 #endif
 751
 752    /* init point span buffer */
 753    swrast->PointSpan.primitive = GL_POINT;
 754    swrast->PointSpan.end = 0;
 755    swrast->PointSpan.facing = 0;
 756    swrast->PointSpan.array = swrast->SpanArrays;
 757
 758    swrast->TexelBuffer = (GLchan *) MALLOC(ctx->Const.MaxTextureImageUnits *
 759                                            MAX_WIDTH * 4 * sizeof(GLchan));
 760    if (!swrast->TexelBuffer) {
 761       FREE(swrast->SpanArrays);
 762       FREE(swrast);
 763       return GL_FALSE;
 764    }
 765
 766    ctx->swrast_context = swrast;
 767
 768    return GL_TRUE;
 769 }
 770
 771 void
 772 _swrast_DestroyContext( GLcontext *ctx )
 773 {
 774    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 775
 776    if (SWRAST_DEBUG) {
 777       _mesa_debug(ctx, "_swrast_DestroyContext\n");
 778    }
 779
 780    FREE( swrast->SpanArrays );
 781    FREE( swrast->TexelBuffer );
 782    FREE( swrast );
 783
 784    ctx->swrast_context = 0;
 785 }
 786
 787
 788 struct swrast_device_driver *
 789 _swrast_GetDeviceDriverReference( GLcontext *ctx )
 790 {
 791    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 792    return &swrast->Driver;
 793 }
 794
 795 void
 796 _swrast_flush( GLcontext *ctx )
 797 {
 798    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 799    /* flush any pending fragments from rendering points */
 800    if (swrast->PointSpan.end > 0) {
 801       if (ctx->Visual.rgbMode) {
 802          _swrast_write_rgba_span(ctx, &(swrast->PointSpan));
 803       }
 804       else {
 805          _swrast_write_index_span(ctx, &(swrast->PointSpan));
 806       }
 807       swrast->PointSpan.end = 0;
 808    }
 809 }
 810
 811 void
 812 _swrast_render_primitive( GLcontext *ctx, GLenum prim )
 813 {
 814    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 815    if (swrast->Primitive == GL_POINTS && prim != GL_POINTS) {
 816       _swrast_flush(ctx);
 817    }
 818    swrast->Primitive = prim;
 819 }
 820
 821
 822 void
 823 _swrast_render_start( GLcontext *ctx )
 824 {
 825    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 826    if (swrast->Driver.SpanRenderStart)
 827       swrast->Driver.SpanRenderStart( ctx );
 828    swrast->PointSpan.end = 0;
 829 }
 830
 831 void
 832 _swrast_render_finish( GLcontext *ctx )
 833 {
 834    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 835    if (swrast->Driver.SpanRenderFinish)
 836       swrast->Driver.SpanRenderFinish( ctx );
 837
 838    _swrast_flush(ctx);
 839 }
 840
 841
 842 #define SWRAST_DEBUG_VERTICES 0
 843
 844 void
 845 _swrast_print_vertex( GLcontext *ctx, const SWvertex *v )
 846 {
 847    GLuint i;
 848
 849    if (SWRAST_DEBUG_VERTICES) {
 850       _mesa_debug(ctx, "win %f %f %f %f\n",
 851                   v->win[0], v->win[1], v->win[2], v->win[3]);
 852
 853       for (i = 0 ; i < ctx->Const.MaxTextureCoordUnits ; i++)
 854          if (ctx->Texture.Unit[i]._ReallyEnabled)
 855             _mesa_debug(ctx, "texcoord[%d] %f %f %f %f\n", i,
 856                         v->attrib[FRAG_ATTRIB_TEX0 + i][0],
 857                         v->attrib[FRAG_ATTRIB_TEX0 + i][1],
 858                         v->attrib[FRAG_ATTRIB_TEX0 + i][2],
 859                         v->attrib[FRAG_ATTRIB_TEX0 + i][3]);
 860
 861 #if CHAN_TYPE == GL_FLOAT
 862       _mesa_debug(ctx, "color %f %f %f %f\n",
 863                   v->color[0], v->color[1], v->color[2], v->color[3]);
 864       _mesa_debug(ctx, "spec %f %f %f %f\n",
 865                   v->specular[0], v->specular[1],
 866                   v->specular[2], v->specular[3]);
 867 #else
 868       _mesa_debug(ctx, "color %d %d %d %d\n",
 869                   v->color[0], v->color[1], v->color[2], v->color[3]);
 870       _mesa_debug(ctx, "spec %d %d %d %d\n",
 871                   v->specular[0], v->specular[1],
 872                   v->specular[2], v->specular[3]);
 873 #endif
 874       _mesa_debug(ctx, "fog %f\n", v->fog);
 875       _mesa_debug(ctx, "index %d\n", v->index);
 876       _mesa_debug(ctx, "pointsize %f\n", v->pointSize);
 877       _mesa_debug(ctx, "\n");
 878    }
 879 }