src/mesa/main/light.c

   1 /* $Id: light.c,v 1.36 2001/02/13 23:55:30 brianp Exp $ */
   2
   3 /*
   4  * Mesa 3-D graphics library
   5  * Version:  3.5
   6  *
   7  * Copyright (C) 1999-2000  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
  27
  28 #ifdef PC_HEADER
  29 #include "all.h"
  30 #else
  31 #include "glheader.h"
  32 #include "colormac.h"
  33 #include "context.h"
  34 #include "enums.h"
  35 #include "light.h"
  36 #include "macros.h"
  37 #include "mem.h"
  38 #include "mmath.h"
  39 #include "simple_list.h"
  40 #include "mtypes.h"
  41
  42 #include "math/m_xform.h"
  43 #include "math/m_matrix.h"
  44 #endif
  45
  46
  47 /* XXX this is a bit of a hack needed for compilation within XFree86 */
  48 #ifndef FLT_MIN
  49 #define FLT_MIN 1e-37
  50 #endif
  51
  52
  53 void
  54 _mesa_ShadeModel( GLenum mode )
  55 {
  56    GET_CURRENT_CONTEXT(ctx);
  57    ASSERT_OUTSIDE_BEGIN_END(ctx);
  58
  59    if (MESA_VERBOSE & VERBOSE_API)
  60       fprintf(stderr, "glShadeModel %s\n", gl_lookup_enum_by_nr(mode));
  61
  62    if (mode != GL_FLAT && mode != GL_SMOOTH) {
  63       gl_error( ctx, GL_INVALID_ENUM, "glShadeModel" );
  64       return;
  65    }
  66
  67    if (ctx->Light.ShadeModel == mode)
  68       return;
  69
  70    FLUSH_VERTICES(ctx, _NEW_LIGHT);
  71    ctx->Light.ShadeModel = mode;
  72    ctx->_TriangleCaps ^= DD_FLATSHADE;
  73    if (ctx->Driver.ShadeModel)
  74       (*ctx->Driver.ShadeModel)( ctx, mode );
  75 }
  76
  77
  78
  79 void
  80 _mesa_Lightf( GLenum light, GLenum pname, GLfloat param )
  81 {
  82    _mesa_Lightfv( light, pname, &param );
  83 }
  84
  85
  86 void
  87 _mesa_Lightfv( GLenum light, GLenum pname, const GLfloat *params )
  88 {
  89    GET_CURRENT_CONTEXT(ctx);
  90    GLint i = (GLint) (light - GL_LIGHT0);
  91    struct gl_light *l = &ctx->Light.Light[i];
  92
  93    if (i < 0 || i >= ctx->Const.MaxLights) {
  94       gl_error( ctx, GL_INVALID_ENUM, "glLight" );
  95       return;
  96    }
  97
  98    switch (pname) {
  99    case GL_AMBIENT:
 100       if (TEST_EQ_4V(l->Ambient, params))
 101          return;
 102       FLUSH_VERTICES(ctx, _NEW_LIGHT);
 103       COPY_4V( l->Ambient, params );
 104       break;
 105    case GL_DIFFUSE:
 106       if (TEST_EQ_4V(l->Diffuse, params))
 107          return;
 108       FLUSH_VERTICES(ctx, _NEW_LIGHT);
 109       COPY_4V( l->Diffuse, params );
 110       break;
 111    case GL_SPECULAR:
 112       if (TEST_EQ_4V(l->Specular, params))
 113          return;
 114       FLUSH_VERTICES(ctx, _NEW_LIGHT);
 115       COPY_4V( l->Specular, params );
 116       break;
 117    case GL_POSITION: {
 118       GLfloat tmp[4];
 119       /* transform position by ModelView matrix */
 120       TRANSFORM_POINT( tmp, ctx->ModelView.m, params );
 121       if (TEST_EQ_4V(l->EyePosition, tmp))
 122          return;
 123       FLUSH_VERTICES(ctx, _NEW_LIGHT);
 124       COPY_4V(l->EyePosition, tmp);
 125       if (l->EyePosition[3] != 0.0F)
 126          l->_Flags |= LIGHT_POSITIONAL;
 127       else
 128          l->_Flags &= ~LIGHT_POSITIONAL;
 129       break;
 130    }
 131    case GL_SPOT_DIRECTION: {
 132       GLfloat tmp[4];
 133       /* transform direction by inverse modelview */
 134       if (ctx->ModelView.flags & MAT_DIRTY_INVERSE) {
 135          _math_matrix_analyse( &ctx->ModelView );
 136       }
 137       TRANSFORM_NORMAL( tmp, params, ctx->ModelView.inv );
 138       if (TEST_EQ_3V(l->EyeDirection, tmp))
 139          return;
 140       FLUSH_VERTICES(ctx, _NEW_LIGHT);
 141       COPY_3V(l->EyeDirection, tmp);
 142       break;
 143    }
 144    case GL_SPOT_EXPONENT:
 145       if (params[0]<0.0 || params[0]>128.0) {
 146          gl_error( ctx, GL_INVALID_VALUE, "glLight" );
 147          return;
 148       }
 149       if (l->SpotExponent == params[0])
 150          return;
 151       FLUSH_VERTICES(ctx, _NEW_LIGHT);
 152       l->SpotExponent = params[0];
 153       gl_invalidate_spot_exp_table( l );
 154       break;
 155    case GL_SPOT_CUTOFF:
 156       if ((params[0]<0.0 || params[0]>90.0) && params[0]!=180.0) {
 157          gl_error( ctx, GL_INVALID_VALUE, "glLight" );
 158          return;
 159       }
 160       if (l->SpotCutoff == params[0])
 161          return;
 162       FLUSH_VERTICES(ctx, _NEW_LIGHT);
 163       l->SpotCutoff = params[0];
 164       l->_CosCutoff = cos(params[0]*DEG2RAD);
 165       if (l->_CosCutoff < 0)
 166          l->_CosCutoff = 0;
 167       if (l->SpotCutoff != 180.0F)
 168          l->_Flags |= LIGHT_SPOT;
 169       else
 170          l->_Flags &= ~LIGHT_SPOT;
 171       break;
 172    case GL_CONSTANT_ATTENUATION:
 173       if (params[0]<0.0) {
 174          gl_error( ctx, GL_INVALID_VALUE, "glLight" );
 175          return;
 176       }
 177       if (l->ConstantAttenuation == params[0])
 178          return;
 179       FLUSH_VERTICES(ctx, _NEW_LIGHT);
 180       l->ConstantAttenuation = params[0];
 181       break;
 182    case GL_LINEAR_ATTENUATION:
 183       if (params[0]<0.0) {
 184          gl_error( ctx, GL_INVALID_VALUE, "glLight" );
 185          return;
 186       }
 187       if (l->LinearAttenuation == params[0])
 188          return;
 189       FLUSH_VERTICES(ctx, _NEW_LIGHT);
 190       l->LinearAttenuation = params[0];
 191       break;
 192    case GL_QUADRATIC_ATTENUATION:
 193       if (params[0]<0.0) {
 194          gl_error( ctx, GL_INVALID_VALUE, "glLight" );
 195          return;
 196       }
 197       if (l->QuadraticAttenuation == params[0])
 198          return;
 199       FLUSH_VERTICES(ctx, _NEW_LIGHT);
 200       l->QuadraticAttenuation = params[0];
 201       break;
 202    default:
 203       gl_error( ctx, GL_INVALID_ENUM, "glLight" );
 204       return;
 205    }
 206
 207    if (ctx->Driver.Lightfv)
 208       ctx->Driver.Lightfv( ctx, light, pname, params );
 209 }
 210
 211
 212 void
 213 _mesa_Lighti( GLenum light, GLenum pname, GLint param )
 214 {
 215    _mesa_Lightiv( light, pname, &param );
 216 }
 217
 218
 219 void
 220 _mesa_Lightiv( GLenum light, GLenum pname, const GLint *params )
 221 {
 222    GLfloat fparam[4];
 223
 224    switch (pname) {
 225       case GL_AMBIENT:
 226       case GL_DIFFUSE:
 227       case GL_SPECULAR:
 228          fparam[0] = INT_TO_FLOAT( params[0] );
 229          fparam[1] = INT_TO_FLOAT( params[1] );
 230          fparam[2] = INT_TO_FLOAT( params[2] );
 231          fparam[3] = INT_TO_FLOAT( params[3] );
 232          break;
 233       case GL_POSITION:
 234          fparam[0] = (GLfloat) params[0];
 235          fparam[1] = (GLfloat) params[1];
 236          fparam[2] = (GLfloat) params[2];
 237          fparam[3] = (GLfloat) params[3];
 238          break;
 239       case GL_SPOT_DIRECTION:
 240          fparam[0] = (GLfloat) params[0];
 241          fparam[1] = (GLfloat) params[1];
 242          fparam[2] = (GLfloat) params[2];
 243          break;
 244       case GL_SPOT_EXPONENT:
 245       case GL_SPOT_CUTOFF:
 246       case GL_CONSTANT_ATTENUATION:
 247       case GL_LINEAR_ATTENUATION:
 248       case GL_QUADRATIC_ATTENUATION:
 249          fparam[0] = (GLfloat) params[0];
 250          break;
 251       default:
 252          /* error will be caught later in gl_Lightfv */
 253          ;
 254    }
 255
 256    _mesa_Lightfv( light, pname, fparam );
 257 }
 258
 259
 260
 261 void
 262 _mesa_GetLightfv( GLenum light, GLenum pname, GLfloat *params )
 263 {
 264    GET_CURRENT_CONTEXT(ctx);
 265    GLint l = (GLint) (light - GL_LIGHT0);
 266    ASSERT_OUTSIDE_BEGIN_END(ctx);
 267
 268    if (l < 0 || l >= ctx->Const.MaxLights) {
 269       gl_error( ctx, GL_INVALID_ENUM, "glGetLightfv" );
 270       return;
 271    }
 272
 273    switch (pname) {
 274       case GL_AMBIENT:
 275          COPY_4V( params, ctx->Light.Light[l].Ambient );
 276          break;
 277       case GL_DIFFUSE:
 278          COPY_4V( params, ctx->Light.Light[l].Diffuse );
 279          break;
 280       case GL_SPECULAR:
 281          COPY_4V( params, ctx->Light.Light[l].Specular );
 282          break;
 283       case GL_POSITION:
 284          COPY_4V( params, ctx->Light.Light[l].EyePosition );
 285          break;
 286       case GL_SPOT_DIRECTION:
 287          COPY_3V( params, ctx->Light.Light[l].EyeDirection );
 288          break;
 289       case GL_SPOT_EXPONENT:
 290          params[0] = ctx->Light.Light[l].SpotExponent;
 291          break;
 292       case GL_SPOT_CUTOFF:
 293          params[0] = ctx->Light.Light[l].SpotCutoff;
 294          break;
 295       case GL_CONSTANT_ATTENUATION:
 296          params[0] = ctx->Light.Light[l].ConstantAttenuation;
 297          break;
 298       case GL_LINEAR_ATTENUATION:
 299          params[0] = ctx->Light.Light[l].LinearAttenuation;
 300          break;
 301       case GL_QUADRATIC_ATTENUATION:
 302          params[0] = ctx->Light.Light[l].QuadraticAttenuation;
 303          break;
 304       default:
 305          gl_error( ctx, GL_INVALID_ENUM, "glGetLightfv" );
 306          break;
 307    }
 308 }
 309
 310
 311
 312 void
 313 _mesa_GetLightiv( GLenum light, GLenum pname, GLint *params )
 314 {
 315    GET_CURRENT_CONTEXT(ctx);
 316    GLint l = (GLint) (light - GL_LIGHT0);
 317    ASSERT_OUTSIDE_BEGIN_END(ctx);
 318
 319    if (l < 0 || l >= ctx->Const.MaxLights) {
 320       gl_error( ctx, GL_INVALID_ENUM, "glGetLightiv" );
 321       return;
 322    }
 323
 324    switch (pname) {
 325       case GL_AMBIENT:
 326          params[0] = FLOAT_TO_INT(ctx->Light.Light[l].Ambient[0]);
 327          params[1] = FLOAT_TO_INT(ctx->Light.Light[l].Ambient[1]);
 328          params[2] = FLOAT_TO_INT(ctx->Light.Light[l].Ambient[2]);
 329          params[3] = FLOAT_TO_INT(ctx->Light.Light[l].Ambient[3]);
 330          break;
 331       case GL_DIFFUSE:
 332          params[0] = FLOAT_TO_INT(ctx->Light.Light[l].Diffuse[0]);
 333          params[1] = FLOAT_TO_INT(ctx->Light.Light[l].Diffuse[1]);
 334          params[2] = FLOAT_TO_INT(ctx->Light.Light[l].Diffuse[2]);
 335          params[3] = FLOAT_TO_INT(ctx->Light.Light[l].Diffuse[3]);
 336          break;
 337       case GL_SPECULAR:
 338          params[0] = FLOAT_TO_INT(ctx->Light.Light[l].Specular[0]);
 339          params[1] = FLOAT_TO_INT(ctx->Light.Light[l].Specular[1]);
 340          params[2] = FLOAT_TO_INT(ctx->Light.Light[l].Specular[2]);
 341          params[3] = FLOAT_TO_INT(ctx->Light.Light[l].Specular[3]);
 342          break;
 343       case GL_POSITION:
 344          params[0] = (GLint) ctx->Light.Light[l].EyePosition[0];
 345          params[1] = (GLint) ctx->Light.Light[l].EyePosition[1];
 346          params[2] = (GLint) ctx->Light.Light[l].EyePosition[2];
 347          params[3] = (GLint) ctx->Light.Light[l].EyePosition[3];
 348          break;
 349       case GL_SPOT_DIRECTION:
 350          params[0] = (GLint) ctx->Light.Light[l].EyeDirection[0];
 351          params[1] = (GLint) ctx->Light.Light[l].EyeDirection[1];
 352          params[2] = (GLint) ctx->Light.Light[l].EyeDirection[2];
 353          break;
 354       case GL_SPOT_EXPONENT:
 355          params[0] = (GLint) ctx->Light.Light[l].SpotExponent;
 356          break;
 357       case GL_SPOT_CUTOFF:
 358          params[0] = (GLint) ctx->Light.Light[l].SpotCutoff;
 359          break;
 360       case GL_CONSTANT_ATTENUATION:
 361          params[0] = (GLint) ctx->Light.Light[l].ConstantAttenuation;
 362          break;
 363       case GL_LINEAR_ATTENUATION:
 364          params[0] = (GLint) ctx->Light.Light[l].LinearAttenuation;
 365          break;
 366       case GL_QUADRATIC_ATTENUATION:
 367          params[0] = (GLint) ctx->Light.Light[l].QuadraticAttenuation;
 368          break;
 369       default:
 370          gl_error( ctx, GL_INVALID_ENUM, "glGetLightiv" );
 371          break;
 372    }
 373 }
 374
 375
 376
 377 /**********************************************************************/
 378 /***                        Light Model                             ***/
 379 /**********************************************************************/
 380
 381
 382 void
 383 _mesa_LightModelfv( GLenum pname, const GLfloat *params )
 384 {
 385    GLenum newenum;
 386    GLboolean newbool;
 387    GET_CURRENT_CONTEXT(ctx);
 388    ASSERT_OUTSIDE_BEGIN_END(ctx);
 389
 390    switch (pname) {
 391       case GL_LIGHT_MODEL_AMBIENT:
 392          if (TEST_EQ_4V( ctx->Light.Model.Ambient, params ))
 393             return;
 394          FLUSH_VERTICES(ctx, _NEW_LIGHT);
 395          COPY_4V( ctx->Light.Model.Ambient, params );
 396          break;
 397       case GL_LIGHT_MODEL_LOCAL_VIEWER:
 398          newbool = (params[0]!=0.0);
 399          if (ctx->Light.Model.LocalViewer == newbool)
 400             return;
 401          FLUSH_VERTICES(ctx, _NEW_LIGHT);
 402          ctx->Light.Model.LocalViewer = newbool;
 403          break;
 404       case GL_LIGHT_MODEL_TWO_SIDE:
 405          newbool = (params[0]!=0.0);
 406          if (ctx->Light.Model.TwoSide == newbool)
 407             return;
 408          FLUSH_VERTICES(ctx, _NEW_LIGHT);
 409          ctx->Light.Model.TwoSide = newbool;
 410          break;
 411       case GL_LIGHT_MODEL_COLOR_CONTROL:
 412          if (params[0] == (GLfloat) GL_SINGLE_COLOR)
 413             newenum = GL_SINGLE_COLOR;
 414          else if (params[0] == (GLfloat) GL_SEPARATE_SPECULAR_COLOR)
 415             newenum = GL_SEPARATE_SPECULAR_COLOR;
 416          else {
 417             gl_error( ctx, GL_INVALID_ENUM, "glLightModel(param)" );
 418             return;
 419          }
 420          if (ctx->Light.Model.ColorControl == newenum)
 421             return;
 422          FLUSH_VERTICES(ctx, _NEW_LIGHT);
 423          ctx->Light.Model.ColorControl = newenum;
 424          ctx->_TriangleCaps ^= DD_SEPERATE_SPECULAR;
 425          break;
 426       default:
 427          gl_error( ctx, GL_INVALID_ENUM, "glLightModel" );
 428          break;
 429    }
 430
 431    if (ctx->Driver.LightModelfv)
 432       ctx->Driver.LightModelfv( ctx, pname, params );
 433 }
 434
 435
 436 void
 437 _mesa_LightModeliv( GLenum pname, const GLint *params )
 438 {
 439    GLfloat fparam[4];
 440
 441    switch (pname) {
 442       case GL_LIGHT_MODEL_AMBIENT:
 443          fparam[0] = INT_TO_FLOAT( params[0] );
 444          fparam[1] = INT_TO_FLOAT( params[1] );
 445          fparam[2] = INT_TO_FLOAT( params[2] );
 446          fparam[3] = INT_TO_FLOAT( params[3] );
 447          break;
 448       case GL_LIGHT_MODEL_LOCAL_VIEWER:
 449       case GL_LIGHT_MODEL_TWO_SIDE:
 450       case GL_LIGHT_MODEL_COLOR_CONTROL:
 451          fparam[0] = (GLfloat) params[0];
 452          break;
 453       default:
 454          /* Error will be caught later in gl_LightModelfv */
 455          ;
 456    }
 457    _mesa_LightModelfv( pname, fparam );
 458 }
 459
 460
 461 void
 462 _mesa_LightModeli( GLenum pname, GLint param )
 463 {
 464    _mesa_LightModeliv( pname, &param );
 465 }
 466
 467
 468 void
 469 _mesa_LightModelf( GLenum pname, GLfloat param )
 470 {
 471    _mesa_LightModelfv( pname, &param );
 472 }
 473
 474
 475
 476 /********** MATERIAL **********/
 477
 478
 479 /*
 480  * Given a face and pname value (ala glColorMaterial), compute a bitmask
 481  * of the targeted material values.
 482  */
 483 GLuint gl_material_bitmask( GLcontext *ctx, GLenum face, GLenum pname,
 484                             GLuint legal,
 485                             const char *where )
 486 {
 487    GLuint bitmask = 0;
 488
 489    /* Make a bitmask indicating what material attribute(s) we're updating */
 490    switch (pname) {
 491       case GL_EMISSION:
 492          bitmask |= FRONT_EMISSION_BIT | BACK_EMISSION_BIT;
 493          break;
 494       case GL_AMBIENT:
 495          bitmask |= FRONT_AMBIENT_BIT | BACK_AMBIENT_BIT;
 496          break;
 497       case GL_DIFFUSE:
 498          bitmask |= FRONT_DIFFUSE_BIT | BACK_DIFFUSE_BIT;
 499          break;
 500       case GL_SPECULAR:
 501          bitmask |= FRONT_SPECULAR_BIT | BACK_SPECULAR_BIT;
 502          break;
 503       case GL_SHININESS:
 504          bitmask |= FRONT_SHININESS_BIT | BACK_SHININESS_BIT;
 505          break;
 506       case GL_AMBIENT_AND_DIFFUSE:
 507          bitmask |= FRONT_AMBIENT_BIT | BACK_AMBIENT_BIT;
 508          bitmask |= FRONT_DIFFUSE_BIT | BACK_DIFFUSE_BIT;
 509          break;
 510       case GL_COLOR_INDEXES:
 511          bitmask |= FRONT_INDEXES_BIT  | BACK_INDEXES_BIT;
 512          break;
 513       default:
 514          gl_error( ctx, GL_INVALID_ENUM, where );
 515          return 0;
 516    }
 517
 518    if (face==GL_FRONT) {
 519       bitmask &= FRONT_MATERIAL_BITS;
 520    }
 521    else if (face==GL_BACK) {
 522       bitmask &= BACK_MATERIAL_BITS;
 523    }
 524    else if (face != GL_FRONT_AND_BACK) {
 525       gl_error( ctx, GL_INVALID_ENUM, where );
 526       return 0;
 527    }
 528
 529    if (bitmask & ~legal) {
 530       gl_error( ctx, GL_INVALID_ENUM, where );
 531       return 0;
 532    }
 533
 534    return bitmask;
 535 }
 536
 537
 538
 539 /*
 540  * Check if the global material has to be updated with info that was
 541  * associated with a vertex via glMaterial.
 542  * This function is used when any material values get changed between
 543  * glBegin/glEnd either by calling glMaterial() or by calling glColor()
 544  * when GL_COLOR_MATERIAL is enabled.
 545  *
 546  * src[0] is front material, src[1] is back material
 547  *
 548  * KW: Added code here to keep the precomputed variables uptodate.
 549  *     This means we can use the faster shade functions when using
 550  *     GL_COLOR_MATERIAL, and we can also now use the precomputed
 551  *     values in the slower shading functions, which further offsets
 552  *     the cost of doing this here.
 553  */
 554 void gl_update_material( GLcontext *ctx,
 555                          const struct gl_material src[2],
 556                          GLuint bitmask )
 557 {
 558    struct gl_light *light, *list = &ctx->Light.EnabledList;
 559
 560    if (ctx->Light.ColorMaterialEnabled)
 561       bitmask &= ~ctx->Light.ColorMaterialBitmask;
 562
 563    if (MESA_VERBOSE&VERBOSE_IMMEDIATE)
 564       fprintf(stderr, "gl_update_material, mask 0x%x\n", bitmask);
 565
 566    if (!bitmask)
 567       return;
 568
 569    /* update material emission */
 570    if (bitmask & FRONT_EMISSION_BIT) {
 571       struct gl_material *mat = &ctx->Light.Material[0];
 572       COPY_4FV( mat->Emission, src[0].Emission );
 573    }
 574    if (bitmask & BACK_EMISSION_BIT) {
 575       struct gl_material *mat = &ctx->Light.Material[1];
 576       COPY_4FV( mat->Emission, src[1].Emission );
 577    }
 578
 579    /* update material ambience */
 580    if (bitmask & FRONT_AMBIENT_BIT) {
 581       struct gl_material *mat = &ctx->Light.Material[0];
 582       COPY_4FV( mat->Ambient, src[0].Ambient );
 583       foreach (light, list) {
 584          SCALE_3V( light->_MatAmbient[0], light->Ambient, src[0].Ambient);
 585       }
 586    }
 587    if (bitmask & BACK_AMBIENT_BIT) {
 588       struct gl_material *mat = &ctx->Light.Material[1];
 589       COPY_4FV( mat->Ambient, src[1].Ambient );
 590       foreach (light, list) {
 591          SCALE_3V( light->_MatAmbient[1], light->Ambient, src[1].Ambient);
 592       }
 593    }
 594
 595    /* update BaseColor = emission + scene's ambience * material's ambience */
 596    if (bitmask & (FRONT_EMISSION_BIT | FRONT_AMBIENT_BIT)) {
 597       struct gl_material *mat = &ctx->Light.Material[0];
 598       COPY_3V( ctx->Light._BaseColor[0], mat->Emission );
 599       ACC_SCALE_3V( ctx->Light._BaseColor[0], mat->Ambient,
 600                     ctx->Light.Model.Ambient );
 601    }
 602    if (bitmask & (BACK_EMISSION_BIT | BACK_AMBIENT_BIT)) {
 603       struct gl_material *mat = &ctx->Light.Material[1];
 604       COPY_3V( ctx->Light._BaseColor[1], mat->Emission );
 605       ACC_SCALE_3V( ctx->Light._BaseColor[1], mat->Ambient,
 606                     ctx->Light.Model.Ambient );
 607    }
 608
 609    /* update material diffuse values */
 610    if (bitmask & FRONT_DIFFUSE_BIT) {
 611       struct gl_material *mat = &ctx->Light.Material[0];
 612       COPY_4FV( mat->Diffuse, src[0].Diffuse );
 613 /*        fprintf(stderr, "FRONT_DIFFUSE %f %f %f %f\n",  */
 614 /*            mat->Diffuse[0], mat->Diffuse[1], */
 615 /*            mat->Diffuse[2], mat->Diffuse[3]); */
 616       foreach (light, list) {
 617          SCALE_3V( light->_MatDiffuse[0], light->Diffuse, mat->Diffuse );
 618       }
 619       UNCLAMPED_FLOAT_TO_CHAN(ctx->Light._BaseAlpha[0], mat->Diffuse[3]);
 620    }
 621    if (bitmask & BACK_DIFFUSE_BIT) {
 622       struct gl_material *mat = &ctx->Light.Material[1];
 623       COPY_4FV( mat->Diffuse, src[1].Diffuse );
 624 /*        fprintf(stderr, "BACK_DIFFUSE %f %f %f %f\n",  */
 625 /*            mat->Diffuse[0], mat->Diffuse[1], */
 626 /*            mat->Diffuse[2], mat->Diffuse[3]); */
 627       foreach (light, list) {
 628          SCALE_3V( light->_MatDiffuse[1], light->Diffuse, mat->Diffuse );
 629       }
 630       UNCLAMPED_FLOAT_TO_CHAN(ctx->Light._BaseAlpha[1], mat->Diffuse[3]);
 631    }
 632
 633    /* update material specular values */
 634    if (bitmask & FRONT_SPECULAR_BIT) {
 635       struct gl_material *mat = &ctx->Light.Material[0];
 636       COPY_4FV( mat->Specular, src[0].Specular );
 637       foreach (light, list) {
 638          SCALE_3V( light->_MatSpecular[0], light->Specular, mat->Specular);
 639       }
 640    }
 641    if (bitmask & BACK_SPECULAR_BIT) {
 642       struct gl_material *mat = &ctx->Light.Material[1];
 643       COPY_4FV( mat->Specular, src[1].Specular );
 644       foreach (light, list) {
 645          SCALE_3V( light->_MatSpecular[1], light->Specular, mat->Specular);
 646       }
 647    }
 648
 649    if (bitmask & FRONT_SHININESS_BIT) {
 650 /*        fprintf(stderr, "FRONT_SHININESS_BIT %f\n", src[0].Shininess); */
 651       ctx->Light.Material[0].Shininess = src[0].Shininess;
 652       gl_invalidate_shine_table( ctx, 0 );
 653    }
 654    if (bitmask & BACK_SHININESS_BIT) {
 655       ctx->Light.Material[1].Shininess = src[1].Shininess;
 656       gl_invalidate_shine_table( ctx, 1 );
 657    }
 658
 659    if (bitmask & FRONT_INDEXES_BIT) {
 660       ctx->Light.Material[0].AmbientIndex = src[0].AmbientIndex;
 661       ctx->Light.Material[0].DiffuseIndex = src[0].DiffuseIndex;
 662       ctx->Light.Material[0].SpecularIndex = src[0].SpecularIndex;
 663    }
 664    if (bitmask & BACK_INDEXES_BIT) {
 665       ctx->Light.Material[1].AmbientIndex = src[1].AmbientIndex;
 666       ctx->Light.Material[1].DiffuseIndex = src[1].DiffuseIndex;
 667       ctx->Light.Material[1].SpecularIndex = src[1].SpecularIndex;
 668    }
 669
 670    if (0)
 671    {
 672       struct gl_material *mat = &ctx->Light.Material[0];
 673       fprintf(stderr, "update_mat  emission : %f %f %f\n",
 674               mat->Emission[0],
 675               mat->Emission[1],
 676               mat->Emission[2]);
 677       fprintf(stderr, "update_mat  specular : %f %f %f\n",
 678               mat->Specular[0],
 679               mat->Specular[1],
 680               mat->Specular[2]);
 681       fprintf(stderr, "update_mat  diffuse : %f %f %f\n",
 682               mat->Diffuse[0],
 683               mat->Diffuse[1],
 684               mat->Diffuse[2]);
 685       fprintf(stderr, "update_mat  ambient : %f %f %f\n",
 686               mat->Ambient[0],
 687               mat->Ambient[1],
 688               mat->Ambient[2]);
 689    }
 690 }
 691
 692
 693
 694
 695 /*
 696  * Update the current materials from the given rgba color
 697  * according to the bitmask in ColorMaterialBitmask, which is
 698  * set by glColorMaterial().
 699  */
 700 void gl_update_color_material( GLcontext *ctx,
 701                                const GLchan rgba[4] )
 702 {
 703    struct gl_light *light, *list = &ctx->Light.EnabledList;
 704    GLuint bitmask = ctx->Light.ColorMaterialBitmask;
 705    GLfloat color[4];
 706
 707    color[0] = CHAN_TO_FLOAT(rgba[0]);
 708    color[1] = CHAN_TO_FLOAT(rgba[1]);
 709    color[2] = CHAN_TO_FLOAT(rgba[2]);
 710    color[3] = CHAN_TO_FLOAT(rgba[3]);
 711
 712    if (MESA_VERBOSE&VERBOSE_IMMEDIATE)
 713       fprintf(stderr, "gl_update_color_material, mask 0x%x\n", bitmask);
 714
 715    /* update emissive colors */
 716    if (bitmask & FRONT_EMISSION_BIT) {
 717       struct gl_material *mat = &ctx->Light.Material[0];
 718       COPY_4FV( mat->Emission, color );
 719    }
 720
 721    if (bitmask & BACK_EMISSION_BIT) {
 722       struct gl_material *mat = &ctx->Light.Material[1];
 723       COPY_4FV( mat->Emission, color );
 724    }
 725
 726    /* update light->_MatAmbient = light's ambient * material's ambient */
 727    if (bitmask & FRONT_AMBIENT_BIT) {
 728       struct gl_material *mat = &ctx->Light.Material[0];
 729       foreach (light, list) {
 730          SCALE_3V( light->_MatAmbient[0], light->Ambient, color);
 731       }
 732       COPY_4FV( mat->Ambient, color );
 733    }
 734
 735    if (bitmask & BACK_AMBIENT_BIT) {
 736       struct gl_material *mat = &ctx->Light.Material[1];
 737       foreach (light, list) {
 738          SCALE_3V( light->_MatAmbient[1], light->Ambient, color);
 739       }
 740       COPY_4FV( mat->Ambient, color );
 741    }
 742
 743    /* update BaseColor = emission + scene's ambience * material's ambience */
 744    if (bitmask & (FRONT_EMISSION_BIT | FRONT_AMBIENT_BIT)) {
 745       struct gl_material *mat = &ctx->Light.Material[0];
 746       COPY_3V( ctx->Light._BaseColor[0], mat->Emission );
 747       ACC_SCALE_3V( ctx->Light._BaseColor[0], mat->Ambient, ctx->Light.Model.Ambient );
 748    }
 749
 750    if (bitmask & (BACK_EMISSION_BIT | BACK_AMBIENT_BIT)) {
 751       struct gl_material *mat = &ctx->Light.Material[1];
 752       COPY_3V( ctx->Light._BaseColor[1], mat->Emission );
 753       ACC_SCALE_3V( ctx->Light._BaseColor[1], mat->Ambient, ctx->Light.Model.Ambient );
 754    }
 755
 756    /* update light->_MatDiffuse = light's diffuse * material's diffuse */
 757    if (bitmask & FRONT_DIFFUSE_BIT) {
 758       struct gl_material *mat = &ctx->Light.Material[0];
 759       COPY_4FV( mat->Diffuse, color );
 760       foreach (light, list) {
 761          SCALE_3V( light->_MatDiffuse[0], light->Diffuse, mat->Diffuse );
 762       }
 763       UNCLAMPED_FLOAT_TO_CHAN(ctx->Light._BaseAlpha[0], mat->Diffuse[3]);
 764    }
 765
 766    if (bitmask & BACK_DIFFUSE_BIT) {
 767       struct gl_material *mat = &ctx->Light.Material[1];
 768       COPY_4FV( mat->Diffuse, color );
 769       foreach (light, list) {
 770          SCALE_3V( light->_MatDiffuse[1], light->Diffuse, mat->Diffuse );
 771       }
 772       UNCLAMPED_FLOAT_TO_CHAN(ctx->Light._BaseAlpha[1], mat->Diffuse[3]);
 773    }
 774
 775    /* update light->_MatSpecular = light's specular * material's specular */
 776    if (bitmask & FRONT_SPECULAR_BIT) {
 777       struct gl_material *mat = &ctx->Light.Material[0];
 778       COPY_4FV( mat->Specular, color );
 779       foreach (light, list) {
 780          ACC_SCALE_3V( light->_MatSpecular[0], light->Specular, mat->Specular);
 781       }
 782    }
 783
 784    if (bitmask & BACK_SPECULAR_BIT) {
 785       struct gl_material *mat = &ctx->Light.Material[1];
 786       COPY_4FV( mat->Specular, color );
 787       foreach (light, list) {
 788          ACC_SCALE_3V( light->_MatSpecular[1], light->Specular, mat->Specular);
 789       }
 790    }
 791
 792    if (0)
 793    {
 794       struct gl_material *mat = &ctx->Light.Material[0];
 795       fprintf(stderr, "update_color_mat  emission : %f %f %f\n",
 796               mat->Emission[0],
 797               mat->Emission[1],
 798               mat->Emission[2]);
 799       fprintf(stderr, "update_color_mat  specular : %f %f %f\n",
 800               mat->Specular[0],
 801               mat->Specular[1],
 802               mat->Specular[2]);
 803       fprintf(stderr, "update_color_mat  diffuse : %f %f %f\n",
 804               mat->Diffuse[0],
 805               mat->Diffuse[1],
 806               mat->Diffuse[2]);
 807       fprintf(stderr, "update_color_mat  ambient : %f %f %f\n",
 808               mat->Ambient[0],
 809               mat->Ambient[1],
 810               mat->Ambient[2]);
 811    }
 812 }
 813
 814
 815
 816
 817 void
 818 _mesa_ColorMaterial( GLenum face, GLenum mode )
 819 {
 820    GET_CURRENT_CONTEXT(ctx);
 821    GLuint bitmask;
 822    GLuint legal = (FRONT_EMISSION_BIT | BACK_EMISSION_BIT |
 823                    FRONT_SPECULAR_BIT | BACK_SPECULAR_BIT |
 824                    FRONT_DIFFUSE_BIT  | BACK_DIFFUSE_BIT  |
 825                    FRONT_AMBIENT_BIT  | BACK_AMBIENT_BIT);
 826    ASSERT_OUTSIDE_BEGIN_END(ctx);
 827
 828    if (MESA_VERBOSE&VERBOSE_API)
 829       fprintf(stderr, "glColorMaterial %s %s\n",
 830               gl_lookup_enum_by_nr(face),
 831               gl_lookup_enum_by_nr(mode));
 832
 833    bitmask = gl_material_bitmask( ctx, face, mode, legal, "glColorMaterial" );
 834
 835    if (ctx->Light.ColorMaterialBitmask == bitmask &&
 836        ctx->Light.ColorMaterialFace == face &&
 837        ctx->Light.ColorMaterialMode == mode)
 838       return;
 839
 840    FLUSH_VERTICES(ctx, _NEW_LIGHT);
 841    ctx->Light.ColorMaterialBitmask = bitmask;
 842    ctx->Light.ColorMaterialFace = face;
 843    ctx->Light.ColorMaterialMode = mode;
 844
 845    if (ctx->Light.ColorMaterialEnabled) {
 846       FLUSH_CURRENT( ctx, 0 );
 847       gl_update_color_material( ctx, ctx->Current.Color );
 848    }
 849 }
 850
 851
 852
 853
 854
 855 void
 856 _mesa_GetMaterialfv( GLenum face, GLenum pname, GLfloat *params )
 857 {
 858    GET_CURRENT_CONTEXT(ctx);
 859    GLuint f;
 860    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx); /* update materials */
 861
 862    if (face==GL_FRONT) {
 863       f = 0;
 864    }
 865    else if (face==GL_BACK) {
 866       f = 1;
 867    }
 868    else {
 869       gl_error( ctx, GL_INVALID_ENUM, "glGetMaterialfv(face)" );
 870       return;
 871    }
 872    switch (pname) {
 873       case GL_AMBIENT:
 874          COPY_4FV( params, ctx->Light.Material[f].Ambient );
 875          break;
 876       case GL_DIFFUSE:
 877          COPY_4FV( params, ctx->Light.Material[f].Diffuse );
 878          break;
 879       case GL_SPECULAR:
 880          COPY_4FV( params, ctx->Light.Material[f].Specular );
 881          break;
 882       case GL_EMISSION:
 883          COPY_4FV( params, ctx->Light.Material[f].Emission );
 884          break;
 885       case GL_SHININESS:
 886          *params = ctx->Light.Material[f].Shininess;
 887          break;
 888       case GL_COLOR_INDEXES:
 889          params[0] = ctx->Light.Material[f].AmbientIndex;
 890          params[1] = ctx->Light.Material[f].DiffuseIndex;
 891          params[2] = ctx->Light.Material[f].SpecularIndex;
 892          break;
 893       default:
 894          gl_error( ctx, GL_INVALID_ENUM, "glGetMaterialfv(pname)" );
 895    }
 896 }
 897
 898
 899
 900 void
 901 _mesa_GetMaterialiv( GLenum face, GLenum pname, GLint *params )
 902 {
 903    GET_CURRENT_CONTEXT(ctx);
 904    GLuint f;
 905    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx); /* update materials */
 906
 907    if (face==GL_FRONT) {
 908       f = 0;
 909    }
 910    else if (face==GL_BACK) {
 911       f = 1;
 912    }
 913    else {
 914       gl_error( ctx, GL_INVALID_ENUM, "glGetMaterialiv(face)" );
 915       return;
 916    }
 917    switch (pname) {
 918       case GL_AMBIENT:
 919          params[0] = FLOAT_TO_INT( ctx->Light.Material[f].Ambient[0] );
 920          params[1] = FLOAT_TO_INT( ctx->Light.Material[f].Ambient[1] );
 921          params[2] = FLOAT_TO_INT( ctx->Light.Material[f].Ambient[2] );
 922          params[3] = FLOAT_TO_INT( ctx->Light.Material[f].Ambient[3] );
 923          break;
 924       case GL_DIFFUSE:
 925          params[0] = FLOAT_TO_INT( ctx->Light.Material[f].Diffuse[0] );
 926          params[1] = FLOAT_TO_INT( ctx->Light.Material[f].Diffuse[1] );
 927          params[2] = FLOAT_TO_INT( ctx->Light.Material[f].Diffuse[2] );
 928          params[3] = FLOAT_TO_INT( ctx->Light.Material[f].Diffuse[3] );
 929          break;
 930       case GL_SPECULAR:
 931          params[0] = FLOAT_TO_INT( ctx->Light.Material[f].Specular[0] );
 932          params[1] = FLOAT_TO_INT( ctx->Light.Material[f].Specular[1] );
 933          params[2] = FLOAT_TO_INT( ctx->Light.Material[f].Specular[2] );
 934          params[3] = FLOAT_TO_INT( ctx->Light.Material[f].Specular[3] );
 935          break;
 936       case GL_EMISSION:
 937          params[0] = FLOAT_TO_INT( ctx->Light.Material[f].Emission[0] );
 938          params[1] = FLOAT_TO_INT( ctx->Light.Material[f].Emission[1] );
 939          params[2] = FLOAT_TO_INT( ctx->Light.Material[f].Emission[2] );
 940          params[3] = FLOAT_TO_INT( ctx->Light.Material[f].Emission[3] );
 941          break;
 942       case GL_SHININESS:
 943          *params = ROUNDF( ctx->Light.Material[f].Shininess );
 944          break;
 945       case GL_COLOR_INDEXES:
 946          params[0] = ROUNDF( ctx->Light.Material[f].AmbientIndex );
 947          params[1] = ROUNDF( ctx->Light.Material[f].DiffuseIndex );
 948          params[2] = ROUNDF( ctx->Light.Material[f].SpecularIndex );
 949          break;
 950       default:
 951          gl_error( ctx, GL_INVALID_ENUM, "glGetMaterialfv(pname)" );
 952    }
 953 }
 954
 955
 956
 957
 958 /**********************************************************************/
 959 /*****                  Lighting computation                      *****/
 960 /**********************************************************************/
 961
 962
 963 /*
 964  * Notes:
 965  *   When two-sided lighting is enabled we compute the color (or index)
 966  *   for both the front and back side of the primitive.  Then, when the
 967  *   orientation of the facet is later learned, we can determine which
 968  *   color (or index) to use for rendering.
 969  *
 970  *   KW: We now know orientation in advance and only shade for
 971  *       the side or sides which are actually required.
 972  *
 973  * Variables:
 974  *   n = normal vector
 975  *   V = vertex position
 976  *   P = light source position
 977  *   Pe = (0,0,0,1)
 978  *
 979  * Precomputed:
 980  *   IF P[3]==0 THEN
 981  *       // light at infinity
 982  *       IF local_viewer THEN
 983  *           _VP_inf_norm = unit vector from V to P      // Precompute
 984  *       ELSE
 985  *           // eye at infinity
 986  *           _h_inf_norm = Normalize( VP + <0,0,1> )     // Precompute
 987  *       ENDIF
 988  *   ENDIF
 989  *
 990  * Functions:
 991  *   Normalize( v ) = normalized vector v
 992  *   Magnitude( v ) = length of vector v
 993  */
 994
 995
 996
 997 /*
 998  * Whenever the spotlight exponent for a light changes we must call
 999  * this function to recompute the exponent lookup table.
1000  */
1001 void
1002 gl_invalidate_spot_exp_table( struct gl_light *l )
1003 {
1004    l->_SpotExpTable[0][0] = -1;
1005 }
1006
1007 static void validate_spot_exp_table( struct gl_light *l )
1008 {
1009    GLint i;
1010    GLdouble exponent = l->SpotExponent;
1011    GLdouble tmp = 0;
1012    GLint clamp = 0;
1013
1014    l->_SpotExpTable[0][0] = 0.0;
1015
1016    for (i = EXP_TABLE_SIZE - 1; i > 0 ;i--) {
1017       if (clamp == 0) {
1018          tmp = pow(i / (GLdouble) (EXP_TABLE_SIZE - 1), exponent);
1019          if (tmp < FLT_MIN * 100.0) {
1020             tmp = 0.0;
1021             clamp = 1;
1022          }
1023       }
1024       l->_SpotExpTable[i][0] = tmp;
1025    }
1026    for (i = 0; i < EXP_TABLE_SIZE - 1; i++) {
1027       l->_SpotExpTable[i][1] = (l->_SpotExpTable[i+1][0] -
1028                                 l->_SpotExpTable[i][0]);
1029    }
1030    l->_SpotExpTable[EXP_TABLE_SIZE-1][1] = 0.0;
1031 }
1032
1033
1034
1035
1036 /* Calculate a new shine table.  Doing this here saves a branch in
1037  * lighting, and the cost of doing it early may be partially offset
1038  * by keeping a MRU cache of shine tables for various shine values.
1039  */
1040 void
1041 gl_invalidate_shine_table( GLcontext *ctx, GLuint i )
1042 {
1043    if (ctx->_ShineTable[i])
1044       ctx->_ShineTable[i]->refcount--;
1045    ctx->_ShineTable[i] = 0;
1046 }
1047
1048 static void validate_shine_table( GLcontext *ctx, GLuint i, GLfloat shininess )
1049 {
1050    struct gl_shine_tab *list = ctx->_ShineTabList;
1051    struct gl_shine_tab *s;
1052
1053    foreach(s, list)
1054       if ( s->shininess == shininess )
1055          break;
1056
1057    if (s == list) {
1058       GLint j;
1059       GLfloat *m;
1060
1061       foreach(s, list)
1062          if (s->refcount == 0)
1063             break;
1064
1065       m = s->tab;
1066       m[0] = 0.0;
1067       if (shininess == 0.0) {
1068          for (j = 1 ; j <= SHINE_TABLE_SIZE ; j++)
1069             m[j] = 1.0;
1070       }
1071       else {
1072          for (j = 1 ; j < SHINE_TABLE_SIZE ; j++) {
1073             GLdouble t, x = j / (GLfloat) (SHINE_TABLE_SIZE - 1);
1074             if (x < 0.005) /* underflow check */
1075                x = 0.005;
1076             t = pow(x, shininess);
1077             if (t > 1e-20)
1078                m[j] = t;
1079             else
1080                m[j] = 0.0;
1081          }
1082          m[SHINE_TABLE_SIZE] = 1.0;
1083       }
1084
1085       s->shininess = shininess;
1086    }
1087
1088    if (ctx->_ShineTable[i])
1089       ctx->_ShineTable[i]->refcount--;
1090
1091    ctx->_ShineTable[i] = s;
1092    move_to_tail( list, s );
1093    s->refcount++;
1094 }
1095
1096 void
1097 gl_validate_all_lighting_tables( GLcontext *ctx )
1098 {
1099    GLint i;
1100    GLfloat shininess;
1101
1102    shininess = ctx->Light.Material[0].Shininess;
1103    if (!ctx->_ShineTable[0] || ctx->_ShineTable[0]->shininess != shininess)
1104       validate_shine_table( ctx, 0, shininess );
1105
1106    shininess = ctx->Light.Material[1].Shininess;
1107    if (!ctx->_ShineTable[1] || ctx->_ShineTable[1]->shininess != shininess)
1108       validate_shine_table( ctx, 1, shininess );
1109
1110    for (i = 0 ; i < MAX_LIGHTS ; i++)
1111       if (ctx->Light.Light[i]._SpotExpTable[0][0] == -1)
1112          validate_spot_exp_table( &ctx->Light.Light[i] );
1113 }
1114
1115
1116
1117
1118 /*
1119  * Examine current lighting parameters to determine if the optimized lighting
1120  * function can be used.
1121  * Also, precompute some lighting values such as the products of light
1122  * source and material ambient, diffuse and specular coefficients.
1123  */
1124 void
1125 gl_update_lighting( GLcontext *ctx )
1126 {
1127    struct gl_light *light;
1128    ctx->_TriangleCaps &= ~DD_TRI_LIGHT_TWOSIDE;
1129    ctx->_NeedEyeCoords &= ~NEED_EYE_LIGHT;
1130    ctx->_NeedNormals &= ~NEED_NORMALS_LIGHT;
1131    ctx->Light._Flags = 0;
1132
1133    if (!ctx->Light.Enabled)
1134       return;
1135
1136    ctx->_NeedNormals |= NEED_NORMALS_LIGHT;
1137
1138    if (ctx->Light.Model.TwoSide)
1139       ctx->_TriangleCaps |= DD_TRI_LIGHT_TWOSIDE;
1140
1141    foreach(light, &ctx->Light.EnabledList) {
1142       ctx->Light._Flags |= light->_Flags;
1143    }
1144
1145    ctx->Light._NeedVertices =
1146       ((ctx->Light._Flags & (LIGHT_POSITIONAL|LIGHT_SPOT)) ||
1147        ctx->Light.Model.ColorControl == GL_SEPARATE_SPECULAR_COLOR ||
1148        ctx->Light.Model.LocalViewer);
1149
1150    if ((ctx->Light._Flags & LIGHT_POSITIONAL) ||
1151        ctx->Light.Model.LocalViewer)
1152       ctx->_NeedEyeCoords |= NEED_EYE_LIGHT;
1153
1154
1155    /* XXX: This test is overkill & needs to be fixed both for software and
1156     * hardware t&l drivers.  The above should be sufficient & should
1157     * be tested to verify this.
1158     */
1159    if (ctx->Light._NeedVertices)
1160       ctx->_NeedEyeCoords |= NEED_EYE_LIGHT;
1161
1162
1163    /* Precompute some shading values.  Although we reference
1164     * Light.Material here, we can get away without flushing
1165     * FLUSH_UPDATE_CURRENT, as when any outstanding material changes
1166     * are flushed, they will update the derived state at that time.
1167     */
1168    if (ctx->Visual.rgbMode) {
1169       GLuint sides = ctx->Light.Model.TwoSide ? 2 : 1;
1170       GLuint side;
1171       for (side=0; side < sides; side++) {
1172          struct gl_material *mat = &ctx->Light.Material[side];
1173
1174          COPY_3V(ctx->Light._BaseColor[side], mat->Emission);
1175          ACC_SCALE_3V(ctx->Light._BaseColor[side],
1176                       ctx->Light.Model.Ambient,
1177                       mat->Ambient);
1178
1179          UNCLAMPED_FLOAT_TO_CHAN(ctx->Light._BaseAlpha[side],
1180                                  ctx->Light.Material[side].Diffuse[3] );
1181       }
1182
1183       foreach (light, &ctx->Light.EnabledList) {
1184          for (side=0; side< sides; side++) {
1185             const struct gl_material *mat = &ctx->Light.Material[side];
1186             SCALE_3V( light->_MatDiffuse[side], light->Diffuse, mat->Diffuse );
1187             SCALE_3V( light->_MatAmbient[side], light->Ambient, mat->Ambient );
1188             SCALE_3V( light->_MatSpecular[side], light->Specular,
1189                       mat->Specular);
1190          }
1191       }
1192    }
1193    else {
1194       static const GLfloat ci[3] = { .30, .59, .11 };
1195       foreach(light, &ctx->Light.EnabledList) {
1196          light->_dli = DOT3(ci, light->Diffuse);
1197          light->_sli = DOT3(ci, light->Specular);
1198       }
1199    }
1200 }
1201
1202
1203 /* _NEW_MODELVIEW
1204  * _NEW_LIGHT
1205  * _TNL_NEW_NEED_EYE_COORDS
1206  *
1207  * Update on (_NEW_MODELVIEW | _NEW_LIGHT) when lighting is enabled.
1208  * Also update on lighting space changes.
1209  */
1210 void
1211 gl_compute_light_positions( GLcontext *ctx )
1212 {
1213    struct gl_light *light;
1214    static const GLfloat eye_z[3] = { 0, 0, 1 };
1215
1216    if (!ctx->Light.Enabled)
1217       return;
1218
1219    if (ctx->_NeedEyeCoords) {
1220       COPY_3V( ctx->_EyeZDir, eye_z );
1221    }
1222    else {
1223       TRANSFORM_NORMAL( ctx->_EyeZDir, eye_z, ctx->ModelView.m );
1224    }
1225
1226    foreach (light, &ctx->Light.EnabledList) {
1227
1228       if (ctx->_NeedEyeCoords) {
1229          COPY_4FV( light->_Position, light->EyePosition );
1230       }
1231       else {
1232          TRANSFORM_POINT( light->_Position, ctx->ModelView.inv,
1233                           light->EyePosition );
1234       }
1235
1236       if (!(light->_Flags & LIGHT_POSITIONAL)) {
1237          /* VP (VP) = Normalize( Position ) */
1238          COPY_3V( light->_VP_inf_norm, light->_Position );
1239          NORMALIZE_3FV( light->_VP_inf_norm );
1240
1241          if (!ctx->Light.Model.LocalViewer) {
1242             /* _h_inf_norm = Normalize( V_to_P + <0,0,1> ) */
1243             ADD_3V( light->_h_inf_norm, light->_VP_inf_norm, ctx->_EyeZDir);
1244             NORMALIZE_3FV( light->_h_inf_norm );
1245          }
1246          light->_VP_inf_spot_attenuation = 1.0;
1247       }
1248
1249       if (light->_Flags & LIGHT_SPOT) {
1250          if (ctx->_NeedEyeCoords) {
1251             COPY_3V( light->_NormDirection, light->EyeDirection );
1252          }
1253          else {
1254             TRANSFORM_NORMAL( light->_NormDirection,
1255                               light->EyeDirection,
1256                               ctx->ModelView.m);
1257          }
1258
1259          NORMALIZE_3FV( light->_NormDirection );
1260
1261          if (!(light->_Flags & LIGHT_POSITIONAL)) {
1262             GLfloat PV_dot_dir = - DOT3(light->_VP_inf_norm,
1263                                         light->_NormDirection);
1264
1265             if (PV_dot_dir > light->_CosCutoff) {
1266                double x = PV_dot_dir * (EXP_TABLE_SIZE-1);
1267                int k = (int) x;
1268                light->_VP_inf_spot_attenuation =
1269                   (light->_SpotExpTable[k][0] +
1270                    (x-k)*light->_SpotExpTable[k][1]);
1271             }
1272             else {
1273                light->_VP_inf_spot_attenuation = 0;
1274             }
1275          }
1276       }
1277    }
1278 }
1279
1280