src/mesa/main/light.c

   1 /* $Id: light.c,v 1.50 2002/06/13 04:28:29 brianp Exp $ */
   2
   3 /*
   4  * Mesa 3-D graphics library
   5  * Version:  4.1
   6  *
   7  * Copyright (C) 1999-2002  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       _mesa_debug("glShadeModel %s\n", _mesa_lookup_enum_by_nr(mode));
  61
  62    if (mode != GL_FLAT && mode != GL_SMOOTH) {
  63       _mesa_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 >= (GLint) ctx->Const.MaxLights) {
  94       _mesa_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->ModelviewMatrixStack.Top->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->ModelviewMatrixStack.Top->flags & MAT_DIRTY_INVERSE) {
 135          _math_matrix_analyse( ctx->ModelviewMatrixStack.Top );
 136       }
 137       TRANSFORM_NORMAL( tmp, params, ctx->ModelviewMatrixStack.Top->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          _mesa_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       _mesa_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          _mesa_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 = (GLfloat) 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          _mesa_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          _mesa_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          _mesa_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       _mesa_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 >= (GLint) ctx->Const.MaxLights) {
 269       _mesa_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          _mesa_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 >= (GLint) ctx->Const.MaxLights) {
 320       _mesa_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          _mesa_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
 411          if (ctx->Light.Enabled && ctx->Light.Model.TwoSide)
 412             ctx->_TriangleCaps |= DD_TRI_LIGHT_TWOSIDE;
 413          else
 414             ctx->_TriangleCaps &= ~DD_TRI_LIGHT_TWOSIDE;
 415          break;
 416       case GL_LIGHT_MODEL_COLOR_CONTROL:
 417          if (params[0] == (GLfloat) GL_SINGLE_COLOR)
 418             newenum = GL_SINGLE_COLOR;
 419          else if (params[0] == (GLfloat) GL_SEPARATE_SPECULAR_COLOR)
 420             newenum = GL_SEPARATE_SPECULAR_COLOR;
 421          else {
 422             _mesa_error( ctx, GL_INVALID_ENUM, "glLightModel(param)" );
 423             return;
 424          }
 425          if (ctx->Light.Model.ColorControl == newenum)
 426             return;
 427          FLUSH_VERTICES(ctx, _NEW_LIGHT);
 428          ctx->Light.Model.ColorControl = newenum;
 429
 430          if ((ctx->Light.Enabled &&
 431               ctx->Light.Model.ColorControl==GL_SEPARATE_SPECULAR_COLOR)
 432              || ctx->Fog.ColorSumEnabled)
 433             ctx->_TriangleCaps |= DD_SEPARATE_SPECULAR;
 434          else
 435             ctx->_TriangleCaps &= ~DD_SEPARATE_SPECULAR;
 436
 437          break;
 438       default:
 439          _mesa_error( ctx, GL_INVALID_ENUM, "glLightModel" );
 440          break;
 441    }
 442
 443    if (ctx->Driver.LightModelfv)
 444       ctx->Driver.LightModelfv( ctx, pname, params );
 445 }
 446
 447
 448 void
 449 _mesa_LightModeliv( GLenum pname, const GLint *params )
 450 {
 451    GLfloat fparam[4];
 452
 453    switch (pname) {
 454       case GL_LIGHT_MODEL_AMBIENT:
 455          fparam[0] = INT_TO_FLOAT( params[0] );
 456          fparam[1] = INT_TO_FLOAT( params[1] );
 457          fparam[2] = INT_TO_FLOAT( params[2] );
 458          fparam[3] = INT_TO_FLOAT( params[3] );
 459          break;
 460       case GL_LIGHT_MODEL_LOCAL_VIEWER:
 461       case GL_LIGHT_MODEL_TWO_SIDE:
 462       case GL_LIGHT_MODEL_COLOR_CONTROL:
 463          fparam[0] = (GLfloat) params[0];
 464          break;
 465       default:
 466          /* Error will be caught later in gl_LightModelfv */
 467          ;
 468    }
 469    _mesa_LightModelfv( pname, fparam );
 470 }
 471
 472
 473 void
 474 _mesa_LightModeli( GLenum pname, GLint param )
 475 {
 476    _mesa_LightModeliv( pname, &param );
 477 }
 478
 479
 480 void
 481 _mesa_LightModelf( GLenum pname, GLfloat param )
 482 {
 483    _mesa_LightModelfv( pname, &param );
 484 }
 485
 486
 487
 488 /********** MATERIAL **********/
 489
 490
 491 /*
 492  * Given a face and pname value (ala glColorMaterial), compute a bitmask
 493  * of the targeted material values.
 494  */
 495 GLuint
 496 _mesa_material_bitmask( GLcontext *ctx, GLenum face, GLenum pname,
 497                         GLuint legal, const char *where )
 498 {
 499    GLuint bitmask = 0;
 500
 501    /* Make a bitmask indicating what material attribute(s) we're updating */
 502    switch (pname) {
 503       case GL_EMISSION:
 504          bitmask |= FRONT_EMISSION_BIT | BACK_EMISSION_BIT;
 505          break;
 506       case GL_AMBIENT:
 507          bitmask |= FRONT_AMBIENT_BIT | BACK_AMBIENT_BIT;
 508          break;
 509       case GL_DIFFUSE:
 510          bitmask |= FRONT_DIFFUSE_BIT | BACK_DIFFUSE_BIT;
 511          break;
 512       case GL_SPECULAR:
 513          bitmask |= FRONT_SPECULAR_BIT | BACK_SPECULAR_BIT;
 514          break;
 515       case GL_SHININESS:
 516          bitmask |= FRONT_SHININESS_BIT | BACK_SHININESS_BIT;
 517          break;
 518       case GL_AMBIENT_AND_DIFFUSE:
 519          bitmask |= FRONT_AMBIENT_BIT | BACK_AMBIENT_BIT;
 520          bitmask |= FRONT_DIFFUSE_BIT | BACK_DIFFUSE_BIT;
 521          break;
 522       case GL_COLOR_INDEXES:
 523          bitmask |= FRONT_INDEXES_BIT  | BACK_INDEXES_BIT;
 524          break;
 525       default:
 526          _mesa_error( ctx, GL_INVALID_ENUM, where );
 527          return 0;
 528    }
 529
 530    if (face==GL_FRONT) {
 531       bitmask &= FRONT_MATERIAL_BITS;
 532    }
 533    else if (face==GL_BACK) {
 534       bitmask &= BACK_MATERIAL_BITS;
 535    }
 536    else if (face != GL_FRONT_AND_BACK) {
 537       _mesa_error( ctx, GL_INVALID_ENUM, where );
 538       return 0;
 539    }
 540
 541    if (bitmask & ~legal) {
 542       _mesa_error( ctx, GL_INVALID_ENUM, where );
 543       return 0;
 544    }
 545
 546    return bitmask;
 547 }
 548
 549
 550 /* Perform a straight copy between pairs of materials.
 551  */
 552 void _mesa_copy_material_pairs( struct gl_material dst[2],
 553                              const struct gl_material src[2],
 554                              GLuint bitmask )
 555 {
 556    if (bitmask & FRONT_EMISSION_BIT) {
 557       COPY_4FV( dst[0].Emission, src[0].Emission );
 558    }
 559    if (bitmask & BACK_EMISSION_BIT) {
 560       COPY_4FV( dst[1].Emission, src[1].Emission );
 561    }
 562    if (bitmask & FRONT_AMBIENT_BIT) {
 563       COPY_4FV( dst[0].Ambient, src[0].Ambient );
 564    }
 565    if (bitmask & BACK_AMBIENT_BIT) {
 566       COPY_4FV( dst[1].Ambient, src[1].Ambient );
 567    }
 568    if (bitmask & FRONT_DIFFUSE_BIT) {
 569       COPY_4FV( dst[0].Diffuse, src[0].Diffuse );
 570    }
 571    if (bitmask & BACK_DIFFUSE_BIT) {
 572       COPY_4FV( dst[1].Diffuse, src[1].Diffuse );
 573    }
 574    if (bitmask & FRONT_SPECULAR_BIT) {
 575       COPY_4FV( dst[0].Specular, src[0].Specular );
 576    }
 577    if (bitmask & BACK_SPECULAR_BIT) {
 578       COPY_4FV( dst[1].Specular, src[1].Specular );
 579    }
 580    if (bitmask & FRONT_SHININESS_BIT) {
 581       dst[0].Shininess = src[0].Shininess;
 582    }
 583    if (bitmask & BACK_SHININESS_BIT) {
 584       dst[1].Shininess = src[1].Shininess;
 585    }
 586    if (bitmask & FRONT_INDEXES_BIT) {
 587       dst[0].AmbientIndex = src[0].AmbientIndex;
 588       dst[0].DiffuseIndex = src[0].DiffuseIndex;
 589       dst[0].SpecularIndex = src[0].SpecularIndex;
 590    }
 591    if (bitmask & BACK_INDEXES_BIT) {
 592       dst[1].AmbientIndex = src[1].AmbientIndex;
 593       dst[1].DiffuseIndex = src[1].DiffuseIndex;
 594       dst[1].SpecularIndex = src[1].SpecularIndex;
 595    }
 596 }
 597
 598
 599 /*
 600  * Check if the global material has to be updated with info that was
 601  * associated with a vertex via glMaterial.
 602  * This function is used when any material values get changed between
 603  * glBegin/glEnd either by calling glMaterial() or by calling glColor()
 604  * when GL_COLOR_MATERIAL is enabled.
 605  *
 606  * src[0] is front material, src[1] is back material
 607  *
 608  * Additionally keeps the precomputed lighting state uptodate.
 609  */
 610 void _mesa_update_material( GLcontext *ctx,
 611                          const struct gl_material src[2],
 612                          GLuint bitmask )
 613 {
 614    struct gl_light *light, *list = &ctx->Light.EnabledList;
 615
 616    if (ctx->Light.ColorMaterialEnabled)
 617       bitmask &= ~ctx->Light.ColorMaterialBitmask;
 618
 619    if (MESA_VERBOSE&VERBOSE_IMMEDIATE)
 620       _mesa_debug("_mesa_update_material, mask 0x%x\n", bitmask);
 621
 622    if (!bitmask)
 623       return;
 624
 625    /* update material emission */
 626    if (bitmask & FRONT_EMISSION_BIT) {
 627       struct gl_material *mat = &ctx->Light.Material[0];
 628       COPY_4FV( mat->Emission, src[0].Emission );
 629    }
 630    if (bitmask & BACK_EMISSION_BIT) {
 631       struct gl_material *mat = &ctx->Light.Material[1];
 632       COPY_4FV( mat->Emission, src[1].Emission );
 633    }
 634
 635    /* update material ambience */
 636    if (bitmask & FRONT_AMBIENT_BIT) {
 637       struct gl_material *mat = &ctx->Light.Material[0];
 638       COPY_4FV( mat->Ambient, src[0].Ambient );
 639       foreach (light, list) {
 640          SCALE_3V( light->_MatAmbient[0], light->Ambient, src[0].Ambient);
 641       }
 642    }
 643    if (bitmask & BACK_AMBIENT_BIT) {
 644       struct gl_material *mat = &ctx->Light.Material[1];
 645       COPY_4FV( mat->Ambient, src[1].Ambient );
 646       foreach (light, list) {
 647          SCALE_3V( light->_MatAmbient[1], light->Ambient, src[1].Ambient);
 648       }
 649    }
 650
 651    /* update BaseColor = emission + scene's ambience * material's ambience */
 652    if (bitmask & (FRONT_EMISSION_BIT | FRONT_AMBIENT_BIT)) {
 653       struct gl_material *mat = &ctx->Light.Material[0];
 654       COPY_3V( ctx->Light._BaseColor[0], mat->Emission );
 655       ACC_SCALE_3V( ctx->Light._BaseColor[0], mat->Ambient,
 656                     ctx->Light.Model.Ambient );
 657    }
 658    if (bitmask & (BACK_EMISSION_BIT | BACK_AMBIENT_BIT)) {
 659       struct gl_material *mat = &ctx->Light.Material[1];
 660       COPY_3V( ctx->Light._BaseColor[1], mat->Emission );
 661       ACC_SCALE_3V( ctx->Light._BaseColor[1], mat->Ambient,
 662                     ctx->Light.Model.Ambient );
 663    }
 664
 665    /* update material diffuse values */
 666    if (bitmask & FRONT_DIFFUSE_BIT) {
 667       struct gl_material *mat = &ctx->Light.Material[0];
 668       COPY_4FV( mat->Diffuse, src[0].Diffuse );
 669       foreach (light, list) {
 670          SCALE_3V( light->_MatDiffuse[0], light->Diffuse, mat->Diffuse );
 671       }
 672    }
 673    if (bitmask & BACK_DIFFUSE_BIT) {
 674       struct gl_material *mat = &ctx->Light.Material[1];
 675       COPY_4FV( mat->Diffuse, src[1].Diffuse );
 676       foreach (light, list) {
 677          SCALE_3V( light->_MatDiffuse[1], light->Diffuse, mat->Diffuse );
 678       }
 679    }
 680
 681    /* update material specular values */
 682    if (bitmask & FRONT_SPECULAR_BIT) {
 683       struct gl_material *mat = &ctx->Light.Material[0];
 684       COPY_4FV( mat->Specular, src[0].Specular );
 685       foreach (light, list) {
 686          SCALE_3V( light->_MatSpecular[0], light->Specular, mat->Specular);
 687       }
 688    }
 689    if (bitmask & BACK_SPECULAR_BIT) {
 690       struct gl_material *mat = &ctx->Light.Material[1];
 691       COPY_4FV( mat->Specular, src[1].Specular );
 692       foreach (light, list) {
 693          SCALE_3V( light->_MatSpecular[1], light->Specular, mat->Specular);
 694       }
 695    }
 696
 697    if (bitmask & FRONT_SHININESS_BIT) {
 698       ctx->Light.Material[0].Shininess = src[0].Shininess;
 699       _mesa_invalidate_shine_table( ctx, 0 );
 700    }
 701    if (bitmask & BACK_SHININESS_BIT) {
 702       ctx->Light.Material[1].Shininess = src[1].Shininess;
 703       _mesa_invalidate_shine_table( ctx, 1 );
 704    }
 705
 706    if (bitmask & FRONT_INDEXES_BIT) {
 707       ctx->Light.Material[0].AmbientIndex = src[0].AmbientIndex;
 708       ctx->Light.Material[0].DiffuseIndex = src[0].DiffuseIndex;
 709       ctx->Light.Material[0].SpecularIndex = src[0].SpecularIndex;
 710    }
 711    if (bitmask & BACK_INDEXES_BIT) {
 712       ctx->Light.Material[1].AmbientIndex = src[1].AmbientIndex;
 713       ctx->Light.Material[1].DiffuseIndex = src[1].DiffuseIndex;
 714       ctx->Light.Material[1].SpecularIndex = src[1].SpecularIndex;
 715    }
 716
 717    if (0)
 718    {
 719       struct gl_material *mat = &ctx->Light.Material[0];
 720       _mesa_debug("update_mat  emission : %f %f %f\n",
 721               mat->Emission[0],
 722               mat->Emission[1],
 723               mat->Emission[2]);
 724       _mesa_debug("update_mat  specular : %f %f %f\n",
 725               mat->Specular[0],
 726               mat->Specular[1],
 727               mat->Specular[2]);
 728       _mesa_debug("update_mat  diffuse : %f %f %f\n",
 729               mat->Diffuse[0],
 730               mat->Diffuse[1],
 731               mat->Diffuse[2]);
 732       _mesa_debug("update_mat  ambient : %f %f %f\n",
 733               mat->Ambient[0],
 734               mat->Ambient[1],
 735               mat->Ambient[2]);
 736    }
 737 }
 738
 739
 740
 741
 742
 743
 744
 745 /*
 746  * Update the current materials from the given rgba color
 747  * according to the bitmask in ColorMaterialBitmask, which is
 748  * set by glColorMaterial().
 749  */
 750 void _mesa_update_color_material( GLcontext *ctx,
 751                                   const GLfloat color[4] )
 752 {
 753    struct gl_light *light, *list = &ctx->Light.EnabledList;
 754    GLuint bitmask = ctx->Light.ColorMaterialBitmask;
 755
 756    if (MESA_VERBOSE&VERBOSE_IMMEDIATE)
 757       _mesa_debug("_mesa_update_color_material, mask 0x%x\n", bitmask);
 758
 759    /* update emissive colors */
 760    if (bitmask & FRONT_EMISSION_BIT) {
 761       struct gl_material *mat = &ctx->Light.Material[0];
 762       COPY_4FV( mat->Emission, color );
 763    }
 764
 765    if (bitmask & BACK_EMISSION_BIT) {
 766       struct gl_material *mat = &ctx->Light.Material[1];
 767       COPY_4FV( mat->Emission, color );
 768    }
 769
 770    /* update light->_MatAmbient = light's ambient * material's ambient */
 771    if (bitmask & FRONT_AMBIENT_BIT) {
 772       struct gl_material *mat = &ctx->Light.Material[0];
 773       foreach (light, list) {
 774          SCALE_3V( light->_MatAmbient[0], light->Ambient, color);
 775       }
 776       COPY_4FV( mat->Ambient, color );
 777    }
 778
 779    if (bitmask & BACK_AMBIENT_BIT) {
 780       struct gl_material *mat = &ctx->Light.Material[1];
 781       foreach (light, list) {
 782          SCALE_3V( light->_MatAmbient[1], light->Ambient, color);
 783       }
 784       COPY_4FV( mat->Ambient, color );
 785    }
 786
 787    /* update BaseColor = emission + scene's ambience * material's ambience */
 788    if (bitmask & (FRONT_EMISSION_BIT | FRONT_AMBIENT_BIT)) {
 789       struct gl_material *mat = &ctx->Light.Material[0];
 790       COPY_3V( ctx->Light._BaseColor[0], mat->Emission );
 791       ACC_SCALE_3V( ctx->Light._BaseColor[0], mat->Ambient, ctx->Light.Model.Ambient );
 792    }
 793
 794    if (bitmask & (BACK_EMISSION_BIT | BACK_AMBIENT_BIT)) {
 795       struct gl_material *mat = &ctx->Light.Material[1];
 796       COPY_3V( ctx->Light._BaseColor[1], mat->Emission );
 797       ACC_SCALE_3V( ctx->Light._BaseColor[1], mat->Ambient, ctx->Light.Model.Ambient );
 798    }
 799
 800    /* update light->_MatDiffuse = light's diffuse * material's diffuse */
 801    if (bitmask & FRONT_DIFFUSE_BIT) {
 802       struct gl_material *mat = &ctx->Light.Material[0];
 803       COPY_4FV( mat->Diffuse, color );
 804       foreach (light, list) {
 805          SCALE_3V( light->_MatDiffuse[0], light->Diffuse, mat->Diffuse );
 806       }
 807    }
 808
 809    if (bitmask & BACK_DIFFUSE_BIT) {
 810       struct gl_material *mat = &ctx->Light.Material[1];
 811       COPY_4FV( mat->Diffuse, color );
 812       foreach (light, list) {
 813          SCALE_3V( light->_MatDiffuse[1], light->Diffuse, mat->Diffuse );
 814       }
 815    }
 816
 817    /* update light->_MatSpecular = light's specular * material's specular */
 818    if (bitmask & FRONT_SPECULAR_BIT) {
 819       struct gl_material *mat = &ctx->Light.Material[0];
 820       COPY_4FV( mat->Specular, color );
 821       foreach (light, list) {
 822          ACC_SCALE_3V( light->_MatSpecular[0], light->Specular, mat->Specular);
 823       }
 824    }
 825
 826    if (bitmask & BACK_SPECULAR_BIT) {
 827       struct gl_material *mat = &ctx->Light.Material[1];
 828       COPY_4FV( mat->Specular, color );
 829       foreach (light, list) {
 830          ACC_SCALE_3V( light->_MatSpecular[1], light->Specular, mat->Specular);
 831       }
 832    }
 833
 834    if (0)
 835    {
 836       struct gl_material *mat = &ctx->Light.Material[0];
 837       _mesa_debug("update_color_mat  emission : %f %f %f\n",
 838               mat->Emission[0],
 839               mat->Emission[1],
 840               mat->Emission[2]);
 841       _mesa_debug("update_color_mat  specular : %f %f %f\n",
 842               mat->Specular[0],
 843               mat->Specular[1],
 844               mat->Specular[2]);
 845       _mesa_debug("update_color_mat  diffuse : %f %f %f\n",
 846               mat->Diffuse[0],
 847               mat->Diffuse[1],
 848               mat->Diffuse[2]);
 849       _mesa_debug("update_color_mat  ambient : %f %f %f\n",
 850               mat->Ambient[0],
 851               mat->Ambient[1],
 852               mat->Ambient[2]);
 853    }
 854 }
 855
 856
 857
 858
 859 void
 860 _mesa_ColorMaterial( GLenum face, GLenum mode )
 861 {
 862    GET_CURRENT_CONTEXT(ctx);
 863    GLuint bitmask;
 864    GLuint legal = (FRONT_EMISSION_BIT | BACK_EMISSION_BIT |
 865                    FRONT_SPECULAR_BIT | BACK_SPECULAR_BIT |
 866                    FRONT_DIFFUSE_BIT  | BACK_DIFFUSE_BIT  |
 867                    FRONT_AMBIENT_BIT  | BACK_AMBIENT_BIT);
 868    ASSERT_OUTSIDE_BEGIN_END(ctx);
 869
 870    if (MESA_VERBOSE&VERBOSE_API)
 871       _mesa_debug("glColorMaterial %s %s\n",
 872               _mesa_lookup_enum_by_nr(face),
 873               _mesa_lookup_enum_by_nr(mode));
 874
 875    bitmask = _mesa_material_bitmask(ctx, face, mode, legal, "glColorMaterial");
 876
 877    if (ctx->Light.ColorMaterialBitmask == bitmask &&
 878        ctx->Light.ColorMaterialFace == face &&
 879        ctx->Light.ColorMaterialMode == mode)
 880       return;
 881
 882    FLUSH_VERTICES(ctx, _NEW_LIGHT);
 883    ctx->Light.ColorMaterialBitmask = bitmask;
 884    ctx->Light.ColorMaterialFace = face;
 885    ctx->Light.ColorMaterialMode = mode;
 886
 887    if (ctx->Light.ColorMaterialEnabled) {
 888       FLUSH_CURRENT( ctx, 0 );
 889       _mesa_update_color_material(ctx,ctx->Current.Attrib[VERT_ATTRIB_COLOR0]);
 890    }
 891
 892    if (ctx->Driver.ColorMaterial)
 893       (*ctx->Driver.ColorMaterial)( ctx, face, mode );
 894 }
 895
 896
 897
 898
 899
 900 void
 901 _mesa_GetMaterialfv( GLenum face, GLenum pname, GLfloat *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       _mesa_error( ctx, GL_INVALID_ENUM, "glGetMaterialfv(face)" );
 915       return;
 916    }
 917    switch (pname) {
 918       case GL_AMBIENT:
 919          COPY_4FV( params, ctx->Light.Material[f].Ambient );
 920          break;
 921       case GL_DIFFUSE:
 922          COPY_4FV( params, ctx->Light.Material[f].Diffuse );
 923          break;
 924       case GL_SPECULAR:
 925          COPY_4FV( params, ctx->Light.Material[f].Specular );
 926          break;
 927       case GL_EMISSION:
 928          COPY_4FV( params, ctx->Light.Material[f].Emission );
 929          break;
 930       case GL_SHININESS:
 931          *params = ctx->Light.Material[f].Shininess;
 932          break;
 933       case GL_COLOR_INDEXES:
 934          params[0] = ctx->Light.Material[f].AmbientIndex;
 935          params[1] = ctx->Light.Material[f].DiffuseIndex;
 936          params[2] = ctx->Light.Material[f].SpecularIndex;
 937          break;
 938       default:
 939          _mesa_error( ctx, GL_INVALID_ENUM, "glGetMaterialfv(pname)" );
 940    }
 941 }
 942
 943
 944
 945 void
 946 _mesa_GetMaterialiv( GLenum face, GLenum pname, GLint *params )
 947 {
 948    GET_CURRENT_CONTEXT(ctx);
 949    GLuint f;
 950    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx); /* update materials */
 951
 952    if (face==GL_FRONT) {
 953       f = 0;
 954    }
 955    else if (face==GL_BACK) {
 956       f = 1;
 957    }
 958    else {
 959       _mesa_error( ctx, GL_INVALID_ENUM, "glGetMaterialiv(face)" );
 960       return;
 961    }
 962    switch (pname) {
 963       case GL_AMBIENT:
 964          params[0] = FLOAT_TO_INT( ctx->Light.Material[f].Ambient[0] );
 965          params[1] = FLOAT_TO_INT( ctx->Light.Material[f].Ambient[1] );
 966          params[2] = FLOAT_TO_INT( ctx->Light.Material[f].Ambient[2] );
 967          params[3] = FLOAT_TO_INT( ctx->Light.Material[f].Ambient[3] );
 968          break;
 969       case GL_DIFFUSE:
 970          params[0] = FLOAT_TO_INT( ctx->Light.Material[f].Diffuse[0] );
 971          params[1] = FLOAT_TO_INT( ctx->Light.Material[f].Diffuse[1] );
 972          params[2] = FLOAT_TO_INT( ctx->Light.Material[f].Diffuse[2] );
 973          params[3] = FLOAT_TO_INT( ctx->Light.Material[f].Diffuse[3] );
 974          break;
 975       case GL_SPECULAR:
 976          params[0] = FLOAT_TO_INT( ctx->Light.Material[f].Specular[0] );
 977          params[1] = FLOAT_TO_INT( ctx->Light.Material[f].Specular[1] );
 978          params[2] = FLOAT_TO_INT( ctx->Light.Material[f].Specular[2] );
 979          params[3] = FLOAT_TO_INT( ctx->Light.Material[f].Specular[3] );
 980          break;
 981       case GL_EMISSION:
 982          params[0] = FLOAT_TO_INT( ctx->Light.Material[f].Emission[0] );
 983          params[1] = FLOAT_TO_INT( ctx->Light.Material[f].Emission[1] );
 984          params[2] = FLOAT_TO_INT( ctx->Light.Material[f].Emission[2] );
 985          params[3] = FLOAT_TO_INT( ctx->Light.Material[f].Emission[3] );
 986          break;
 987       case GL_SHININESS:
 988          *params = ROUNDF( ctx->Light.Material[f].Shininess );
 989          break;
 990       case GL_COLOR_INDEXES:
 991          params[0] = ROUNDF( ctx->Light.Material[f].AmbientIndex );
 992          params[1] = ROUNDF( ctx->Light.Material[f].DiffuseIndex );
 993          params[2] = ROUNDF( ctx->Light.Material[f].SpecularIndex );
 994          break;
 995       default:
 996          _mesa_error( ctx, GL_INVALID_ENUM, "glGetMaterialfv(pname)" );
 997    }
 998 }
 999
1000
1001
1002
1003 /**********************************************************************/
1004 /*****                  Lighting computation                      *****/
1005 /**********************************************************************/
1006
1007
1008 /*
1009  * Notes:
1010  *   When two-sided lighting is enabled we compute the color (or index)
1011  *   for both the front and back side of the primitive.  Then, when the
1012  *   orientation of the facet is later learned, we can determine which
1013  *   color (or index) to use for rendering.
1014  *
1015  *   KW: We now know orientation in advance and only shade for
1016  *       the side or sides which are actually required.
1017  *
1018  * Variables:
1019  *   n = normal vector
1020  *   V = vertex position
1021  *   P = light source position
1022  *   Pe = (0,0,0,1)
1023  *
1024  * Precomputed:
1025  *   IF P[3]==0 THEN
1026  *       // light at infinity
1027  *       IF local_viewer THEN
1028  *           _VP_inf_norm = unit vector from V to P      // Precompute
1029  *       ELSE
1030  *           // eye at infinity
1031  *           _h_inf_norm = Normalize( VP + <0,0,1> )     // Precompute
1032  *       ENDIF
1033  *   ENDIF
1034  *
1035  * Functions:
1036  *   Normalize( v ) = normalized vector v
1037  *   Magnitude( v ) = length of vector v
1038  */
1039
1040
1041
1042 /*
1043  * Whenever the spotlight exponent for a light changes we must call
1044  * this function to recompute the exponent lookup table.
1045  */
1046 void
1047 _mesa_invalidate_spot_exp_table( struct gl_light *l )
1048 {
1049    l->_SpotExpTable[0][0] = -1;
1050 }
1051
1052 static void validate_spot_exp_table( struct gl_light *l )
1053 {
1054    GLint i;
1055    GLdouble exponent = l->SpotExponent;
1056    GLdouble tmp = 0;
1057    GLint clamp = 0;
1058
1059    l->_SpotExpTable[0][0] = 0.0;
1060
1061    for (i = EXP_TABLE_SIZE - 1; i > 0 ;i--) {
1062       if (clamp == 0) {
1063          tmp = pow(i / (GLdouble) (EXP_TABLE_SIZE - 1), exponent);
1064          if (tmp < FLT_MIN * 100.0) {
1065             tmp = 0.0;
1066             clamp = 1;
1067          }
1068       }
1069       l->_SpotExpTable[i][0] = (GLfloat) tmp;
1070    }
1071    for (i = 0; i < EXP_TABLE_SIZE - 1; i++) {
1072       l->_SpotExpTable[i][1] = (l->_SpotExpTable[i+1][0] -
1073                                 l->_SpotExpTable[i][0]);
1074    }
1075    l->_SpotExpTable[EXP_TABLE_SIZE-1][1] = 0.0;
1076 }
1077
1078
1079
1080
1081 /* Calculate a new shine table.  Doing this here saves a branch in
1082  * lighting, and the cost of doing it early may be partially offset
1083  * by keeping a MRU cache of shine tables for various shine values.
1084  */
1085 void
1086 _mesa_invalidate_shine_table( GLcontext *ctx, GLuint i )
1087 {
1088    if (ctx->_ShineTable[i])
1089       ctx->_ShineTable[i]->refcount--;
1090    ctx->_ShineTable[i] = 0;
1091 }
1092
1093 static void validate_shine_table( GLcontext *ctx, GLuint i, GLfloat shininess )
1094 {
1095    struct gl_shine_tab *list = ctx->_ShineTabList;
1096    struct gl_shine_tab *s;
1097
1098    foreach(s, list)
1099       if ( s->shininess == shininess )
1100          break;
1101
1102    if (s == list) {
1103       GLint j;
1104       GLfloat *m;
1105
1106       foreach(s, list)
1107          if (s->refcount == 0)
1108             break;
1109
1110       m = s->tab;
1111       m[0] = 0.0;
1112       if (shininess == 0.0) {
1113          for (j = 1 ; j <= SHINE_TABLE_SIZE ; j++)
1114             m[j] = 1.0;
1115       }
1116       else {
1117          for (j = 1 ; j < SHINE_TABLE_SIZE ; j++) {
1118             GLdouble t, x = j / (GLfloat) (SHINE_TABLE_SIZE - 1);
1119             if (x < 0.005) /* underflow check */
1120                x = 0.005;
1121             t = pow(x, shininess);
1122             if (t > 1e-20)
1123                m[j] = (GLfloat) t;
1124             else
1125                m[j] = 0.0;
1126          }
1127          m[SHINE_TABLE_SIZE] = 1.0;
1128       }
1129
1130       s->shininess = shininess;
1131    }
1132
1133    if (ctx->_ShineTable[i])
1134       ctx->_ShineTable[i]->refcount--;
1135
1136    ctx->_ShineTable[i] = s;
1137    move_to_tail( list, s );
1138    s->refcount++;
1139 }
1140
1141 void
1142 _mesa_validate_all_lighting_tables( GLcontext *ctx )
1143 {
1144    GLint i;
1145    GLfloat shininess;
1146
1147    shininess = ctx->Light.Material[0].Shininess;
1148    if (!ctx->_ShineTable[0] || ctx->_ShineTable[0]->shininess != shininess)
1149       validate_shine_table( ctx, 0, shininess );
1150
1151    shininess = ctx->Light.Material[1].Shininess;
1152    if (!ctx->_ShineTable[1] || ctx->_ShineTable[1]->shininess != shininess)
1153       validate_shine_table( ctx, 1, shininess );
1154
1155    for (i = 0 ; i < MAX_LIGHTS ; i++)
1156       if (ctx->Light.Light[i]._SpotExpTable[0][0] == -1)
1157          validate_spot_exp_table( &ctx->Light.Light[i] );
1158 }
1159
1160
1161
1162
1163 /*
1164  * Examine current lighting parameters to determine if the optimized lighting
1165  * function can be used.
1166  * Also, precompute some lighting values such as the products of light
1167  * source and material ambient, diffuse and specular coefficients.
1168  */
1169 void
1170 _mesa_update_lighting( GLcontext *ctx )
1171 {
1172    struct gl_light *light;
1173    ctx->_NeedEyeCoords &= ~NEED_EYE_LIGHT;
1174    ctx->_NeedNormals &= ~NEED_NORMALS_LIGHT;
1175    ctx->Light._Flags = 0;
1176
1177    if (!ctx->Light.Enabled)
1178       return;
1179
1180    ctx->_NeedNormals |= NEED_NORMALS_LIGHT;
1181
1182    foreach(light, &ctx->Light.EnabledList) {
1183       ctx->Light._Flags |= light->_Flags;
1184    }
1185
1186    ctx->Light._NeedVertices =
1187       ((ctx->Light._Flags & (LIGHT_POSITIONAL|LIGHT_SPOT)) ||
1188        ctx->Light.Model.ColorControl == GL_SEPARATE_SPECULAR_COLOR ||
1189        ctx->Light.Model.LocalViewer);
1190
1191    if ((ctx->Light._Flags & LIGHT_POSITIONAL) ||
1192        ctx->Light.Model.LocalViewer)
1193       ctx->_NeedEyeCoords |= NEED_EYE_LIGHT;
1194
1195
1196    /* XXX: This test is overkill & needs to be fixed both for software and
1197     * hardware t&l drivers.  The above should be sufficient & should
1198     * be tested to verify this.
1199     */
1200    if (ctx->Light._NeedVertices)
1201       ctx->_NeedEyeCoords |= NEED_EYE_LIGHT;
1202
1203
1204    /* Precompute some shading values.  Although we reference
1205     * Light.Material here, we can get away without flushing
1206     * FLUSH_UPDATE_CURRENT, as when any outstanding material changes
1207     * are flushed, they will update the derived state at that time.
1208     */
1209    if (ctx->Visual.rgbMode) {
1210       GLuint sides = ctx->Light.Model.TwoSide ? 2 : 1;
1211       GLuint side;
1212       for (side=0; side < sides; side++) {
1213          struct gl_material *mat = &ctx->Light.Material[side];
1214
1215          COPY_3V(ctx->Light._BaseColor[side], mat->Emission);
1216          ACC_SCALE_3V(ctx->Light._BaseColor[side],
1217                       ctx->Light.Model.Ambient,
1218                       mat->Ambient);
1219       }
1220
1221       foreach (light, &ctx->Light.EnabledList) {
1222          for (side=0; side< sides; side++) {
1223             const struct gl_material *mat = &ctx->Light.Material[side];
1224             SCALE_3V( light->_MatDiffuse[side], light->Diffuse, mat->Diffuse );
1225             SCALE_3V( light->_MatAmbient[side], light->Ambient, mat->Ambient );
1226             SCALE_3V( light->_MatSpecular[side], light->Specular,
1227                       mat->Specular);
1228          }
1229       }
1230    }
1231    else {
1232       static const GLfloat ci[3] = { .30F, .59F, .11F };
1233       foreach(light, &ctx->Light.EnabledList) {
1234          light->_dli = DOT3(ci, light->Diffuse);
1235          light->_sli = DOT3(ci, light->Specular);
1236       }
1237    }
1238 }
1239
1240
1241 /* _NEW_MODELVIEW
1242  * _NEW_LIGHT
1243  * _TNL_NEW_NEED_EYE_COORDS
1244  *
1245  * Update on (_NEW_MODELVIEW | _NEW_LIGHT) when lighting is enabled.
1246  * Also update on lighting space changes.
1247  */
1248 void
1249 _mesa_compute_light_positions( GLcontext *ctx )
1250 {
1251    struct gl_light *light;
1252    static const GLfloat eye_z[3] = { 0, 0, 1 };
1253
1254    if (!ctx->Light.Enabled)
1255       return;
1256
1257    if (ctx->_NeedEyeCoords) {
1258       COPY_3V( ctx->_EyeZDir, eye_z );
1259    }
1260    else {
1261       TRANSFORM_NORMAL( ctx->_EyeZDir, eye_z, ctx->ModelviewMatrixStack.Top->m );
1262    }
1263
1264    foreach (light, &ctx->Light.EnabledList) {
1265
1266       if (ctx->_NeedEyeCoords) {
1267          COPY_4FV( light->_Position, light->EyePosition );
1268       }
1269       else {
1270          TRANSFORM_POINT( light->_Position, ctx->ModelviewMatrixStack.Top->inv,
1271                           light->EyePosition );
1272       }
1273
1274       if (!(light->_Flags & LIGHT_POSITIONAL)) {
1275          /* VP (VP) = Normalize( Position ) */
1276          COPY_3V( light->_VP_inf_norm, light->_Position );
1277          NORMALIZE_3FV( light->_VP_inf_norm );
1278
1279          if (!ctx->Light.Model.LocalViewer) {
1280             /* _h_inf_norm = Normalize( V_to_P + <0,0,1> ) */
1281             ADD_3V( light->_h_inf_norm, light->_VP_inf_norm, ctx->_EyeZDir);
1282             NORMALIZE_3FV( light->_h_inf_norm );
1283          }
1284          light->_VP_inf_spot_attenuation = 1.0;
1285       }
1286
1287       if (light->_Flags & LIGHT_SPOT) {
1288          if (ctx->_NeedEyeCoords) {
1289             COPY_3V( light->_NormDirection, light->EyeDirection );
1290          }
1291          else {
1292             TRANSFORM_NORMAL( light->_NormDirection,
1293                               light->EyeDirection,
1294                               ctx->ModelviewMatrixStack.Top->m);
1295          }
1296
1297          NORMALIZE_3FV( light->_NormDirection );
1298
1299          if (!(light->_Flags & LIGHT_POSITIONAL)) {
1300             GLfloat PV_dot_dir = - DOT3(light->_VP_inf_norm,
1301                                         light->_NormDirection);
1302
1303             if (PV_dot_dir > light->_CosCutoff) {
1304                double x = PV_dot_dir * (EXP_TABLE_SIZE-1);
1305                int k = (int) x;
1306                light->_VP_inf_spot_attenuation =
1307                   (GLfloat) (light->_SpotExpTable[k][0] +
1308                    (x-k)*light->_SpotExpTable[k][1]);
1309             }
1310             else {
1311                light->_VP_inf_spot_attenuation = 0;
1312             }
1313          }
1314       }
1315    }
1316 }