src/mesa/main/light.c

   1 /* $Id: light.c,v 1.55 2003/03/01 01:50:21 brianp Exp $ */
   2
   3 /*
   4  * Mesa 3-D graphics library
   5  * Version:  5.1
   6  *
   7  * Copyright (C) 1999-2003  Brian Paul   All Rights Reserved.
   8  *
   9  * Permission is hereby granted, free of charge, to any person obtaining a
  10  * copy of this software and associated documentation files (the "Software"),
  11  * to deal in the Software without restriction, including without limitation
  12  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  13  * and/or sell copies of the Software, and to permit persons to whom the
  14  * Software is furnished to do so, subject to the following conditions:
  15  *
  16  * The above copyright notice and this permission notice shall be included
  17  * in all copies or substantial portions of the Software.
  18  *
  19  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  20  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  21  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  22  * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
  23  * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  24  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  25  */
  26
  27
  28 #include "glheader.h"
  29 #include "imports.h"
  30 #include "colormac.h"
  31 #include "context.h"
  32 #include "enums.h"
  33 #include "light.h"
  34 #include "macros.h"
  35 #include "simple_list.h"
  36 #include "mtypes.h"
  37 #include "math/m_xform.h"
  38 #include "math/m_matrix.h"
  39
  40
  41 /* XXX this is a bit of a hack needed for compilation within XFree86 */
  42 #ifndef FLT_MIN
  43 #define FLT_MIN 1e-37
  44 #endif
  45
  46
  47 void
  48 _mesa_ShadeModel( GLenum mode )
  49 {
  50    GET_CURRENT_CONTEXT(ctx);
  51    ASSERT_OUTSIDE_BEGIN_END(ctx);
  52
  53    if (MESA_VERBOSE & VERBOSE_API)
  54       _mesa_debug(ctx, "glShadeModel %s\n", _mesa_lookup_enum_by_nr(mode));
  55
  56    if (mode != GL_FLAT && mode != GL_SMOOTH) {
  57       _mesa_error( ctx, GL_INVALID_ENUM, "glShadeModel" );
  58       return;
  59    }
  60
  61    if (ctx->Light.ShadeModel == mode)
  62       return;
  63
  64    FLUSH_VERTICES(ctx, _NEW_LIGHT);
  65    ctx->Light.ShadeModel = mode;
  66    ctx->_TriangleCaps ^= DD_FLATSHADE;
  67    if (ctx->Driver.ShadeModel)
  68       (*ctx->Driver.ShadeModel)( ctx, mode );
  69 }
  70
  71
  72
  73 void
  74 _mesa_Lightf( GLenum light, GLenum pname, GLfloat param )
  75 {
  76    _mesa_Lightfv( light, pname, &param );
  77 }
  78
  79
  80 void
  81 _mesa_Lightfv( GLenum light, GLenum pname, const GLfloat *params )
  82 {
  83    GET_CURRENT_CONTEXT(ctx);
  84    GLint i = (GLint) (light - GL_LIGHT0);
  85    struct gl_light *l = &ctx->Light.Light[i];
  86
  87    if (i < 0 || i >= (GLint) ctx->Const.MaxLights) {
  88       _mesa_error( ctx, GL_INVALID_ENUM, "glLight(light=0x%x)", light );
  89       return;
  90    }
  91
  92    switch (pname) {
  93    case GL_AMBIENT:
  94       if (TEST_EQ_4V(l->Ambient, params))
  95          return;
  96       FLUSH_VERTICES(ctx, _NEW_LIGHT);
  97       COPY_4V( l->Ambient, params );
  98       break;
  99    case GL_DIFFUSE:
 100       if (TEST_EQ_4V(l->Diffuse, params))
 101          return;
 102       FLUSH_VERTICES(ctx, _NEW_LIGHT);
 103       COPY_4V( l->Diffuse, params );
 104       break;
 105    case GL_SPECULAR:
 106       if (TEST_EQ_4V(l->Specular, params))
 107          return;
 108       FLUSH_VERTICES(ctx, _NEW_LIGHT);
 109       COPY_4V( l->Specular, params );
 110       break;
 111    case GL_POSITION: {
 112       GLfloat tmp[4];
 113       /* transform position by ModelView matrix */
 114       TRANSFORM_POINT( tmp, ctx->ModelviewMatrixStack.Top->m, params );
 115       if (TEST_EQ_4V(l->EyePosition, tmp))
 116          return;
 117       FLUSH_VERTICES(ctx, _NEW_LIGHT);
 118       COPY_4V(l->EyePosition, tmp);
 119       if (l->EyePosition[3] != 0.0F)
 120          l->_Flags |= LIGHT_POSITIONAL;
 121       else
 122          l->_Flags &= ~LIGHT_POSITIONAL;
 123       break;
 124    }
 125    case GL_SPOT_DIRECTION: {
 126       GLfloat tmp[4];
 127       /* transform direction by inverse modelview */
 128       if (ctx->ModelviewMatrixStack.Top->flags & MAT_DIRTY_INVERSE) {
 129          _math_matrix_analyse( ctx->ModelviewMatrixStack.Top );
 130       }
 131       TRANSFORM_NORMAL( tmp, params, ctx->ModelviewMatrixStack.Top->inv );
 132       if (TEST_EQ_3V(l->EyeDirection, tmp))
 133          return;
 134       FLUSH_VERTICES(ctx, _NEW_LIGHT);
 135       COPY_3V(l->EyeDirection, tmp);
 136       break;
 137    }
 138    case GL_SPOT_EXPONENT:
 139       if (params[0]<0.0 || params[0]>128.0) {
 140          _mesa_error( ctx, GL_INVALID_VALUE, "glLight" );
 141          return;
 142       }
 143       if (l->SpotExponent == params[0])
 144          return;
 145       FLUSH_VERTICES(ctx, _NEW_LIGHT);
 146       l->SpotExponent = params[0];
 147       _mesa_invalidate_spot_exp_table( l );
 148       break;
 149    case GL_SPOT_CUTOFF:
 150       if ((params[0]<0.0 || params[0]>90.0) && params[0]!=180.0) {
 151          _mesa_error( ctx, GL_INVALID_VALUE, "glLight" );
 152          return;
 153       }
 154       if (l->SpotCutoff == params[0])
 155          return;
 156       FLUSH_VERTICES(ctx, _NEW_LIGHT);
 157       l->SpotCutoff = params[0];
 158       l->_CosCutoff = (GLfloat) _mesa_cos(params[0]*DEG2RAD);
 159       if (l->_CosCutoff < 0)
 160          l->_CosCutoff = 0;
 161       if (l->SpotCutoff != 180.0F)
 162          l->_Flags |= LIGHT_SPOT;
 163       else
 164          l->_Flags &= ~LIGHT_SPOT;
 165       break;
 166    case GL_CONSTANT_ATTENUATION:
 167       if (params[0]<0.0) {
 168          _mesa_error( ctx, GL_INVALID_VALUE, "glLight" );
 169          return;
 170       }
 171       if (l->ConstantAttenuation == params[0])
 172          return;
 173       FLUSH_VERTICES(ctx, _NEW_LIGHT);
 174       l->ConstantAttenuation = params[0];
 175       break;
 176    case GL_LINEAR_ATTENUATION:
 177       if (params[0]<0.0) {
 178          _mesa_error( ctx, GL_INVALID_VALUE, "glLight" );
 179          return;
 180       }
 181       if (l->LinearAttenuation == params[0])
 182          return;
 183       FLUSH_VERTICES(ctx, _NEW_LIGHT);
 184       l->LinearAttenuation = params[0];
 185       break;
 186    case GL_QUADRATIC_ATTENUATION:
 187       if (params[0]<0.0) {
 188          _mesa_error( ctx, GL_INVALID_VALUE, "glLight" );
 189          return;
 190       }
 191       if (l->QuadraticAttenuation == params[0])
 192          return;
 193       FLUSH_VERTICES(ctx, _NEW_LIGHT);
 194       l->QuadraticAttenuation = params[0];
 195       break;
 196    default:
 197       _mesa_error( ctx, GL_INVALID_ENUM, "glLight(pname=0x%x)", pname );
 198       return;
 199    }
 200
 201    if (ctx->Driver.Lightfv)
 202       ctx->Driver.Lightfv( ctx, light, pname, params );
 203 }
 204
 205
 206 void
 207 _mesa_Lighti( GLenum light, GLenum pname, GLint param )
 208 {
 209    _mesa_Lightiv( light, pname, &param );
 210 }
 211
 212
 213 void
 214 _mesa_Lightiv( GLenum light, GLenum pname, const GLint *params )
 215 {
 216    GLfloat fparam[4];
 217
 218    switch (pname) {
 219       case GL_AMBIENT:
 220       case GL_DIFFUSE:
 221       case GL_SPECULAR:
 222          fparam[0] = INT_TO_FLOAT( params[0] );
 223          fparam[1] = INT_TO_FLOAT( params[1] );
 224          fparam[2] = INT_TO_FLOAT( params[2] );
 225          fparam[3] = INT_TO_FLOAT( params[3] );
 226          break;
 227       case GL_POSITION:
 228          fparam[0] = (GLfloat) params[0];
 229          fparam[1] = (GLfloat) params[1];
 230          fparam[2] = (GLfloat) params[2];
 231          fparam[3] = (GLfloat) params[3];
 232          break;
 233       case GL_SPOT_DIRECTION:
 234          fparam[0] = (GLfloat) params[0];
 235          fparam[1] = (GLfloat) params[1];
 236          fparam[2] = (GLfloat) params[2];
 237          break;
 238       case GL_SPOT_EXPONENT:
 239       case GL_SPOT_CUTOFF:
 240       case GL_CONSTANT_ATTENUATION:
 241       case GL_LINEAR_ATTENUATION:
 242       case GL_QUADRATIC_ATTENUATION:
 243          fparam[0] = (GLfloat) params[0];
 244          break;
 245       default:
 246          /* error will be caught later in gl_Lightfv */
 247          ;
 248    }
 249
 250    _mesa_Lightfv( light, pname, fparam );
 251 }
 252
 253
 254
 255 void
 256 _mesa_GetLightfv( GLenum light, GLenum pname, GLfloat *params )
 257 {
 258    GET_CURRENT_CONTEXT(ctx);
 259    GLint l = (GLint) (light - GL_LIGHT0);
 260    ASSERT_OUTSIDE_BEGIN_END(ctx);
 261
 262    if (l < 0 || l >= (GLint) ctx->Const.MaxLights) {
 263       _mesa_error( ctx, GL_INVALID_ENUM, "glGetLightfv" );
 264       return;
 265    }
 266
 267    switch (pname) {
 268       case GL_AMBIENT:
 269          COPY_4V( params, ctx->Light.Light[l].Ambient );
 270          break;
 271       case GL_DIFFUSE:
 272          COPY_4V( params, ctx->Light.Light[l].Diffuse );
 273          break;
 274       case GL_SPECULAR:
 275          COPY_4V( params, ctx->Light.Light[l].Specular );
 276          break;
 277       case GL_POSITION:
 278          COPY_4V( params, ctx->Light.Light[l].EyePosition );
 279          break;
 280       case GL_SPOT_DIRECTION:
 281          COPY_3V( params, ctx->Light.Light[l].EyeDirection );
 282          break;
 283       case GL_SPOT_EXPONENT:
 284          params[0] = ctx->Light.Light[l].SpotExponent;
 285          break;
 286       case GL_SPOT_CUTOFF:
 287          params[0] = ctx->Light.Light[l].SpotCutoff;
 288          break;
 289       case GL_CONSTANT_ATTENUATION:
 290          params[0] = ctx->Light.Light[l].ConstantAttenuation;
 291          break;
 292       case GL_LINEAR_ATTENUATION:
 293          params[0] = ctx->Light.Light[l].LinearAttenuation;
 294          break;
 295       case GL_QUADRATIC_ATTENUATION:
 296          params[0] = ctx->Light.Light[l].QuadraticAttenuation;
 297          break;
 298       default:
 299          _mesa_error( ctx, GL_INVALID_ENUM, "glGetLightfv" );
 300          break;
 301    }
 302 }
 303
 304
 305
 306 void
 307 _mesa_GetLightiv( GLenum light, GLenum pname, GLint *params )
 308 {
 309    GET_CURRENT_CONTEXT(ctx);
 310    GLint l = (GLint) (light - GL_LIGHT0);
 311    ASSERT_OUTSIDE_BEGIN_END(ctx);
 312
 313    if (l < 0 || l >= (GLint) ctx->Const.MaxLights) {
 314       _mesa_error( ctx, GL_INVALID_ENUM, "glGetLightiv" );
 315       return;
 316    }
 317
 318    switch (pname) {
 319       case GL_AMBIENT:
 320          params[0] = FLOAT_TO_INT(ctx->Light.Light[l].Ambient[0]);
 321          params[1] = FLOAT_TO_INT(ctx->Light.Light[l].Ambient[1]);
 322          params[2] = FLOAT_TO_INT(ctx->Light.Light[l].Ambient[2]);
 323          params[3] = FLOAT_TO_INT(ctx->Light.Light[l].Ambient[3]);
 324          break;
 325       case GL_DIFFUSE:
 326          params[0] = FLOAT_TO_INT(ctx->Light.Light[l].Diffuse[0]);
 327          params[1] = FLOAT_TO_INT(ctx->Light.Light[l].Diffuse[1]);
 328          params[2] = FLOAT_TO_INT(ctx->Light.Light[l].Diffuse[2]);
 329          params[3] = FLOAT_TO_INT(ctx->Light.Light[l].Diffuse[3]);
 330          break;
 331       case GL_SPECULAR:
 332          params[0] = FLOAT_TO_INT(ctx->Light.Light[l].Specular[0]);
 333          params[1] = FLOAT_TO_INT(ctx->Light.Light[l].Specular[1]);
 334          params[2] = FLOAT_TO_INT(ctx->Light.Light[l].Specular[2]);
 335          params[3] = FLOAT_TO_INT(ctx->Light.Light[l].Specular[3]);
 336          break;
 337       case GL_POSITION:
 338          params[0] = (GLint) ctx->Light.Light[l].EyePosition[0];
 339          params[1] = (GLint) ctx->Light.Light[l].EyePosition[1];
 340          params[2] = (GLint) ctx->Light.Light[l].EyePosition[2];
 341          params[3] = (GLint) ctx->Light.Light[l].EyePosition[3];
 342          break;
 343       case GL_SPOT_DIRECTION:
 344          params[0] = (GLint) ctx->Light.Light[l].EyeDirection[0];
 345          params[1] = (GLint) ctx->Light.Light[l].EyeDirection[1];
 346          params[2] = (GLint) ctx->Light.Light[l].EyeDirection[2];
 347          break;
 348       case GL_SPOT_EXPONENT:
 349          params[0] = (GLint) ctx->Light.Light[l].SpotExponent;
 350          break;
 351       case GL_SPOT_CUTOFF:
 352          params[0] = (GLint) ctx->Light.Light[l].SpotCutoff;
 353          break;
 354       case GL_CONSTANT_ATTENUATION:
 355          params[0] = (GLint) ctx->Light.Light[l].ConstantAttenuation;
 356          break;
 357       case GL_LINEAR_ATTENUATION:
 358          params[0] = (GLint) ctx->Light.Light[l].LinearAttenuation;
 359          break;
 360       case GL_QUADRATIC_ATTENUATION:
 361          params[0] = (GLint) ctx->Light.Light[l].QuadraticAttenuation;
 362          break;
 363       default:
 364          _mesa_error( ctx, GL_INVALID_ENUM, "glGetLightiv" );
 365          break;
 366    }
 367 }
 368
 369
 370
 371 /**********************************************************************/
 372 /***                        Light Model                             ***/
 373 /**********************************************************************/
 374
 375
 376 void
 377 _mesa_LightModelfv( GLenum pname, const GLfloat *params )
 378 {
 379    GLenum newenum;
 380    GLboolean newbool;
 381    GET_CURRENT_CONTEXT(ctx);
 382    ASSERT_OUTSIDE_BEGIN_END(ctx);
 383
 384    switch (pname) {
 385       case GL_LIGHT_MODEL_AMBIENT:
 386          if (TEST_EQ_4V( ctx->Light.Model.Ambient, params ))
 387             return;
 388          FLUSH_VERTICES(ctx, _NEW_LIGHT);
 389          COPY_4V( ctx->Light.Model.Ambient, params );
 390          break;
 391       case GL_LIGHT_MODEL_LOCAL_VIEWER:
 392          newbool = (params[0]!=0.0);
 393          if (ctx->Light.Model.LocalViewer == newbool)
 394             return;
 395          FLUSH_VERTICES(ctx, _NEW_LIGHT);
 396          ctx->Light.Model.LocalViewer = newbool;
 397          break;
 398       case GL_LIGHT_MODEL_TWO_SIDE:
 399          newbool = (params[0]!=0.0);
 400          if (ctx->Light.Model.TwoSide == newbool)
 401             return;
 402          FLUSH_VERTICES(ctx, _NEW_LIGHT);
 403          ctx->Light.Model.TwoSide = newbool;
 404
 405          if (ctx->Light.Enabled && ctx->Light.Model.TwoSide)
 406             ctx->_TriangleCaps |= DD_TRI_LIGHT_TWOSIDE;
 407          else
 408             ctx->_TriangleCaps &= ~DD_TRI_LIGHT_TWOSIDE;
 409          break;
 410       case GL_LIGHT_MODEL_COLOR_CONTROL:
 411          if (params[0] == (GLfloat) GL_SINGLE_COLOR)
 412             newenum = GL_SINGLE_COLOR;
 413          else if (params[0] == (GLfloat) GL_SEPARATE_SPECULAR_COLOR)
 414             newenum = GL_SEPARATE_SPECULAR_COLOR;
 415          else {
 416             _mesa_error( ctx, GL_INVALID_ENUM, "glLightModel(param=0x0%x)",
 417                          (GLint) params[0] );
 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
 425          if ((ctx->Light.Enabled &&
 426               ctx->Light.Model.ColorControl==GL_SEPARATE_SPECULAR_COLOR)
 427              || ctx->Fog.ColorSumEnabled)
 428             ctx->_TriangleCaps |= DD_SEPARATE_SPECULAR;
 429          else
 430             ctx->_TriangleCaps &= ~DD_SEPARATE_SPECULAR;
 431
 432          break;
 433       default:
 434          _mesa_error( ctx, GL_INVALID_ENUM, "glLightModel(pname=0x%x)", pname );
 435          break;
 436    }
 437
 438    if (ctx->Driver.LightModelfv)
 439       ctx->Driver.LightModelfv( ctx, pname, params );
 440 }
 441
 442
 443 void
 444 _mesa_LightModeliv( GLenum pname, const GLint *params )
 445 {
 446    GLfloat fparam[4];
 447
 448    switch (pname) {
 449       case GL_LIGHT_MODEL_AMBIENT:
 450          fparam[0] = INT_TO_FLOAT( params[0] );
 451          fparam[1] = INT_TO_FLOAT( params[1] );
 452          fparam[2] = INT_TO_FLOAT( params[2] );
 453          fparam[3] = INT_TO_FLOAT( params[3] );
 454          break;
 455       case GL_LIGHT_MODEL_LOCAL_VIEWER:
 456       case GL_LIGHT_MODEL_TWO_SIDE:
 457       case GL_LIGHT_MODEL_COLOR_CONTROL:
 458          fparam[0] = (GLfloat) params[0];
 459          break;
 460       default:
 461          /* Error will be caught later in gl_LightModelfv */
 462          ;
 463    }
 464    _mesa_LightModelfv( pname, fparam );
 465 }
 466
 467
 468 void
 469 _mesa_LightModeli( GLenum pname, GLint param )
 470 {
 471    _mesa_LightModeliv( pname, &param );
 472 }
 473
 474
 475 void
 476 _mesa_LightModelf( GLenum pname, GLfloat param )
 477 {
 478    _mesa_LightModelfv( pname, &param );
 479 }
 480
 481
 482
 483 /********** MATERIAL **********/
 484
 485
 486 /*
 487  * Given a face and pname value (ala glColorMaterial), compute a bitmask
 488  * of the targeted material values.
 489  */
 490 GLuint
 491 _mesa_material_bitmask( GLcontext *ctx, GLenum face, GLenum pname,
 492                         GLuint legal, const char *where )
 493 {
 494    GLuint bitmask = 0;
 495
 496    /* Make a bitmask indicating what material attribute(s) we're updating */
 497    switch (pname) {
 498       case GL_EMISSION:
 499          bitmask |= FRONT_EMISSION_BIT | BACK_EMISSION_BIT;
 500          break;
 501       case GL_AMBIENT:
 502          bitmask |= FRONT_AMBIENT_BIT | BACK_AMBIENT_BIT;
 503          break;
 504       case GL_DIFFUSE:
 505          bitmask |= FRONT_DIFFUSE_BIT | BACK_DIFFUSE_BIT;
 506          break;
 507       case GL_SPECULAR:
 508          bitmask |= FRONT_SPECULAR_BIT | BACK_SPECULAR_BIT;
 509          break;
 510       case GL_SHININESS:
 511          bitmask |= FRONT_SHININESS_BIT | BACK_SHININESS_BIT;
 512          break;
 513       case GL_AMBIENT_AND_DIFFUSE:
 514          bitmask |= FRONT_AMBIENT_BIT | BACK_AMBIENT_BIT;
 515          bitmask |= FRONT_DIFFUSE_BIT | BACK_DIFFUSE_BIT;
 516          break;
 517       case GL_COLOR_INDEXES:
 518          bitmask |= FRONT_INDEXES_BIT  | BACK_INDEXES_BIT;
 519          break;
 520       default:
 521          _mesa_error( ctx, GL_INVALID_ENUM, where );
 522          return 0;
 523    }
 524
 525    if (face==GL_FRONT) {
 526       bitmask &= FRONT_MATERIAL_BITS;
 527    }
 528    else if (face==GL_BACK) {
 529       bitmask &= BACK_MATERIAL_BITS;
 530    }
 531    else if (face != GL_FRONT_AND_BACK) {
 532       _mesa_error( ctx, GL_INVALID_ENUM, where );
 533       return 0;
 534    }
 535
 536    if (bitmask & ~legal) {
 537       _mesa_error( ctx, GL_INVALID_ENUM, where );
 538       return 0;
 539    }
 540
 541    return bitmask;
 542 }
 543
 544
 545 /* Perform a straight copy between pairs of materials.
 546  */
 547 void _mesa_copy_material_pairs( struct gl_material dst[2],
 548                              const struct gl_material src[2],
 549                              GLuint bitmask )
 550 {
 551    if (bitmask & FRONT_EMISSION_BIT) {
 552       COPY_4FV( dst[0].Emission, src[0].Emission );
 553    }
 554    if (bitmask & BACK_EMISSION_BIT) {
 555       COPY_4FV( dst[1].Emission, src[1].Emission );
 556    }
 557    if (bitmask & FRONT_AMBIENT_BIT) {
 558       COPY_4FV( dst[0].Ambient, src[0].Ambient );
 559    }
 560    if (bitmask & BACK_AMBIENT_BIT) {
 561       COPY_4FV( dst[1].Ambient, src[1].Ambient );
 562    }
 563    if (bitmask & FRONT_DIFFUSE_BIT) {
 564       COPY_4FV( dst[0].Diffuse, src[0].Diffuse );
 565    }
 566    if (bitmask & BACK_DIFFUSE_BIT) {
 567       COPY_4FV( dst[1].Diffuse, src[1].Diffuse );
 568    }
 569    if (bitmask & FRONT_SPECULAR_BIT) {
 570       COPY_4FV( dst[0].Specular, src[0].Specular );
 571    }
 572    if (bitmask & BACK_SPECULAR_BIT) {
 573       COPY_4FV( dst[1].Specular, src[1].Specular );
 574    }
 575    if (bitmask & FRONT_SHININESS_BIT) {
 576       dst[0].Shininess = src[0].Shininess;
 577    }
 578    if (bitmask & BACK_SHININESS_BIT) {
 579       dst[1].Shininess = src[1].Shininess;
 580    }
 581    if (bitmask & FRONT_INDEXES_BIT) {
 582       dst[0].AmbientIndex = src[0].AmbientIndex;
 583       dst[0].DiffuseIndex = src[0].DiffuseIndex;
 584       dst[0].SpecularIndex = src[0].SpecularIndex;
 585    }
 586    if (bitmask & BACK_INDEXES_BIT) {
 587       dst[1].AmbientIndex = src[1].AmbientIndex;
 588       dst[1].DiffuseIndex = src[1].DiffuseIndex;
 589       dst[1].SpecularIndex = src[1].SpecularIndex;
 590    }
 591 }
 592
 593
 594 /*
 595  * Check if the global material has to be updated with info that was
 596  * associated with a vertex via glMaterial.
 597  * This function is used when any material values get changed between
 598  * glBegin/glEnd either by calling glMaterial() or by calling glColor()
 599  * when GL_COLOR_MATERIAL is enabled.
 600  *
 601  * src[0] is front material, src[1] is back material
 602  *
 603  * Additionally keeps the precomputed lighting state uptodate.
 604  */
 605 void _mesa_update_material( GLcontext *ctx,
 606                          const struct gl_material src[2],
 607                          GLuint bitmask )
 608 {
 609    struct gl_light *light, *list = &ctx->Light.EnabledList;
 610
 611    if (ctx->Light.ColorMaterialEnabled)
 612       bitmask &= ~ctx->Light.ColorMaterialBitmask;
 613
 614    if (MESA_VERBOSE&VERBOSE_IMMEDIATE)
 615       _mesa_debug(ctx, "_mesa_update_material, mask 0x%x\n", bitmask);
 616
 617    if (!bitmask)
 618       return;
 619
 620    /* update material emission */
 621    if (bitmask & FRONT_EMISSION_BIT) {
 622       struct gl_material *mat = &ctx->Light.Material[0];
 623       COPY_4FV( mat->Emission, src[0].Emission );
 624    }
 625    if (bitmask & BACK_EMISSION_BIT) {
 626       struct gl_material *mat = &ctx->Light.Material[1];
 627       COPY_4FV( mat->Emission, src[1].Emission );
 628    }
 629
 630    /* update material ambience */
 631    if (bitmask & FRONT_AMBIENT_BIT) {
 632       struct gl_material *mat = &ctx->Light.Material[0];
 633       COPY_4FV( mat->Ambient, src[0].Ambient );
 634       foreach (light, list) {
 635          SCALE_3V( light->_MatAmbient[0], light->Ambient, src[0].Ambient);
 636       }
 637    }
 638    if (bitmask & BACK_AMBIENT_BIT) {
 639       struct gl_material *mat = &ctx->Light.Material[1];
 640       COPY_4FV( mat->Ambient, src[1].Ambient );
 641       foreach (light, list) {
 642          SCALE_3V( light->_MatAmbient[1], light->Ambient, src[1].Ambient);
 643       }
 644    }
 645
 646    /* update BaseColor = emission + scene's ambience * material's ambience */
 647    if (bitmask & (FRONT_EMISSION_BIT | FRONT_AMBIENT_BIT)) {
 648       struct gl_material *mat = &ctx->Light.Material[0];
 649       COPY_3V( ctx->Light._BaseColor[0], mat->Emission );
 650       ACC_SCALE_3V( ctx->Light._BaseColor[0], mat->Ambient,
 651                     ctx->Light.Model.Ambient );
 652    }
 653    if (bitmask & (BACK_EMISSION_BIT | BACK_AMBIENT_BIT)) {
 654       struct gl_material *mat = &ctx->Light.Material[1];
 655       COPY_3V( ctx->Light._BaseColor[1], mat->Emission );
 656       ACC_SCALE_3V( ctx->Light._BaseColor[1], mat->Ambient,
 657                     ctx->Light.Model.Ambient );
 658    }
 659
 660    /* update material diffuse values */
 661    if (bitmask & FRONT_DIFFUSE_BIT) {
 662       struct gl_material *mat = &ctx->Light.Material[0];
 663       COPY_4FV( mat->Diffuse, src[0].Diffuse );
 664       foreach (light, list) {
 665          SCALE_3V( light->_MatDiffuse[0], light->Diffuse, mat->Diffuse );
 666       }
 667    }
 668    if (bitmask & BACK_DIFFUSE_BIT) {
 669       struct gl_material *mat = &ctx->Light.Material[1];
 670       COPY_4FV( mat->Diffuse, src[1].Diffuse );
 671       foreach (light, list) {
 672          SCALE_3V( light->_MatDiffuse[1], light->Diffuse, mat->Diffuse );
 673       }
 674    }
 675
 676    /* update material specular values */
 677    if (bitmask & FRONT_SPECULAR_BIT) {
 678       struct gl_material *mat = &ctx->Light.Material[0];
 679       COPY_4FV( mat->Specular, src[0].Specular );
 680       foreach (light, list) {
 681          SCALE_3V( light->_MatSpecular[0], light->Specular, mat->Specular);
 682       }
 683    }
 684    if (bitmask & BACK_SPECULAR_BIT) {
 685       struct gl_material *mat = &ctx->Light.Material[1];
 686       COPY_4FV( mat->Specular, src[1].Specular );
 687       foreach (light, list) {
 688          SCALE_3V( light->_MatSpecular[1], light->Specular, mat->Specular);
 689       }
 690    }
 691
 692    if (bitmask & FRONT_SHININESS_BIT) {
 693       ctx->Light.Material[0].Shininess = src[0].Shininess;
 694       _mesa_invalidate_shine_table( ctx, 0 );
 695    }
 696    if (bitmask & BACK_SHININESS_BIT) {
 697       ctx->Light.Material[1].Shininess = src[1].Shininess;
 698       _mesa_invalidate_shine_table( ctx, 1 );
 699    }
 700
 701    if (bitmask & FRONT_INDEXES_BIT) {
 702       ctx->Light.Material[0].AmbientIndex = src[0].AmbientIndex;
 703       ctx->Light.Material[0].DiffuseIndex = src[0].DiffuseIndex;
 704       ctx->Light.Material[0].SpecularIndex = src[0].SpecularIndex;
 705    }
 706    if (bitmask & BACK_INDEXES_BIT) {
 707       ctx->Light.Material[1].AmbientIndex = src[1].AmbientIndex;
 708       ctx->Light.Material[1].DiffuseIndex = src[1].DiffuseIndex;
 709       ctx->Light.Material[1].SpecularIndex = src[1].SpecularIndex;
 710    }
 711
 712    if (0) {
 713       struct gl_material *mat = &ctx->Light.Material[0];
 714       _mesa_debug(ctx, "update_mat  emission : %f %f %f\n",
 715                   mat->Emission[0], mat->Emission[1], mat->Emission[2]);
 716       _mesa_debug(ctx, "update_mat  specular : %f %f %f\n",
 717                   mat->Specular[0], mat->Specular[1], mat->Specular[2]);
 718       _mesa_debug(ctx, "update_mat  diffuse : %f %f %f\n",
 719                   mat->Diffuse[0], mat->Diffuse[1], mat->Diffuse[2]);
 720       _mesa_debug(ctx, "update_mat  ambient : %f %f %f\n",
 721                   mat->Ambient[0], mat->Ambient[1], mat->Ambient[2]);
 722    }
 723 }
 724
 725
 726
 727
 728
 729
 730
 731 /*
 732  * Update the current materials from the given rgba color
 733  * according to the bitmask in ColorMaterialBitmask, which is
 734  * set by glColorMaterial().
 735  */
 736 void _mesa_update_color_material( GLcontext *ctx,
 737                                   const GLfloat color[4] )
 738 {
 739    struct gl_light *light, *list = &ctx->Light.EnabledList;
 740    GLuint bitmask = ctx->Light.ColorMaterialBitmask;
 741
 742    if (MESA_VERBOSE&VERBOSE_IMMEDIATE)
 743       _mesa_debug(ctx, "_mesa_update_color_material, mask 0x%x\n", bitmask);
 744
 745    /* update emissive colors */
 746    if (bitmask & FRONT_EMISSION_BIT) {
 747       struct gl_material *mat = &ctx->Light.Material[0];
 748       COPY_4FV( mat->Emission, color );
 749    }
 750
 751    if (bitmask & BACK_EMISSION_BIT) {
 752       struct gl_material *mat = &ctx->Light.Material[1];
 753       COPY_4FV( mat->Emission, color );
 754    }
 755
 756    /* update light->_MatAmbient = light's ambient * material's ambient */
 757    if (bitmask & FRONT_AMBIENT_BIT) {
 758       struct gl_material *mat = &ctx->Light.Material[0];
 759       foreach (light, list) {
 760          SCALE_3V( light->_MatAmbient[0], light->Ambient, color);
 761       }
 762       COPY_4FV( mat->Ambient, color );
 763    }
 764
 765    if (bitmask & BACK_AMBIENT_BIT) {
 766       struct gl_material *mat = &ctx->Light.Material[1];
 767       foreach (light, list) {
 768          SCALE_3V( light->_MatAmbient[1], light->Ambient, color);
 769       }
 770       COPY_4FV( mat->Ambient, color );
 771    }
 772
 773    /* update BaseColor = emission + scene's ambience * material's ambience */
 774    if (bitmask & (FRONT_EMISSION_BIT | FRONT_AMBIENT_BIT)) {
 775       struct gl_material *mat = &ctx->Light.Material[0];
 776       COPY_3V( ctx->Light._BaseColor[0], mat->Emission );
 777       ACC_SCALE_3V( ctx->Light._BaseColor[0], mat->Ambient, ctx->Light.Model.Ambient );
 778    }
 779
 780    if (bitmask & (BACK_EMISSION_BIT | BACK_AMBIENT_BIT)) {
 781       struct gl_material *mat = &ctx->Light.Material[1];
 782       COPY_3V( ctx->Light._BaseColor[1], mat->Emission );
 783       ACC_SCALE_3V( ctx->Light._BaseColor[1], mat->Ambient, ctx->Light.Model.Ambient );
 784    }
 785
 786    /* update light->_MatDiffuse = light's diffuse * material's diffuse */
 787    if (bitmask & FRONT_DIFFUSE_BIT) {
 788       struct gl_material *mat = &ctx->Light.Material[0];
 789       COPY_4FV( mat->Diffuse, color );
 790       foreach (light, list) {
 791          SCALE_3V( light->_MatDiffuse[0], light->Diffuse, mat->Diffuse );
 792       }
 793    }
 794
 795    if (bitmask & BACK_DIFFUSE_BIT) {
 796       struct gl_material *mat = &ctx->Light.Material[1];
 797       COPY_4FV( mat->Diffuse, color );
 798       foreach (light, list) {
 799          SCALE_3V( light->_MatDiffuse[1], light->Diffuse, mat->Diffuse );
 800       }
 801    }
 802
 803    /* update light->_MatSpecular = light's specular * material's specular */
 804    if (bitmask & FRONT_SPECULAR_BIT) {
 805       struct gl_material *mat = &ctx->Light.Material[0];
 806       COPY_4FV( mat->Specular, color );
 807       foreach (light, list) {
 808          ACC_SCALE_3V( light->_MatSpecular[0], light->Specular, mat->Specular);
 809       }
 810    }
 811
 812    if (bitmask & BACK_SPECULAR_BIT) {
 813       struct gl_material *mat = &ctx->Light.Material[1];
 814       COPY_4FV( mat->Specular, color );
 815       foreach (light, list) {
 816          ACC_SCALE_3V( light->_MatSpecular[1], light->Specular, mat->Specular);
 817       }
 818    }
 819
 820    if (0) {
 821       struct gl_material *mat = &ctx->Light.Material[0];
 822       _mesa_debug(ctx, "update_color_mat  emission : %f %f %f\n",
 823                   mat->Emission[0], mat->Emission[1], mat->Emission[2]);
 824       _mesa_debug(ctx, "update_color_mat  specular : %f %f %f\n",
 825                   mat->Specular[0], mat->Specular[1], mat->Specular[2]);
 826       _mesa_debug(ctx, "update_color_mat  diffuse : %f %f %f\n",
 827                   mat->Diffuse[0], mat->Diffuse[1], mat->Diffuse[2]);
 828       _mesa_debug(ctx, "update_color_mat  ambient : %f %f %f\n",
 829                   mat->Ambient[0], mat->Ambient[1], mat->Ambient[2]);
 830    }
 831 }
 832
 833
 834
 835
 836 void
 837 _mesa_ColorMaterial( GLenum face, GLenum mode )
 838 {
 839    GET_CURRENT_CONTEXT(ctx);
 840    GLuint bitmask;
 841    GLuint legal = (FRONT_EMISSION_BIT | BACK_EMISSION_BIT |
 842                    FRONT_SPECULAR_BIT | BACK_SPECULAR_BIT |
 843                    FRONT_DIFFUSE_BIT  | BACK_DIFFUSE_BIT  |
 844                    FRONT_AMBIENT_BIT  | BACK_AMBIENT_BIT);
 845    ASSERT_OUTSIDE_BEGIN_END(ctx);
 846
 847    if (MESA_VERBOSE&VERBOSE_API)
 848       _mesa_debug(ctx, "glColorMaterial %s %s\n",
 849                   _mesa_lookup_enum_by_nr(face),
 850                   _mesa_lookup_enum_by_nr(mode));
 851
 852    bitmask = _mesa_material_bitmask(ctx, face, mode, legal, "glColorMaterial");
 853
 854    if (ctx->Light.ColorMaterialBitmask == bitmask &&
 855        ctx->Light.ColorMaterialFace == face &&
 856        ctx->Light.ColorMaterialMode == mode)
 857       return;
 858
 859    FLUSH_VERTICES(ctx, _NEW_LIGHT);
 860    ctx->Light.ColorMaterialBitmask = bitmask;
 861    ctx->Light.ColorMaterialFace = face;
 862    ctx->Light.ColorMaterialMode = mode;
 863
 864    if (ctx->Light.ColorMaterialEnabled) {
 865       FLUSH_CURRENT( ctx, 0 );
 866       _mesa_update_color_material(ctx,ctx->Current.Attrib[VERT_ATTRIB_COLOR0]);
 867    }
 868
 869    if (ctx->Driver.ColorMaterial)
 870       (*ctx->Driver.ColorMaterial)( ctx, face, mode );
 871 }
 872
 873
 874
 875
 876
 877 void
 878 _mesa_GetMaterialfv( GLenum face, GLenum pname, GLfloat *params )
 879 {
 880    GET_CURRENT_CONTEXT(ctx);
 881    GLuint f;
 882    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx); /* update materials */
 883
 884    if (face==GL_FRONT) {
 885       f = 0;
 886    }
 887    else if (face==GL_BACK) {
 888       f = 1;
 889    }
 890    else {
 891       _mesa_error( ctx, GL_INVALID_ENUM, "glGetMaterialfv(face)" );
 892       return;
 893    }
 894    switch (pname) {
 895       case GL_AMBIENT:
 896          COPY_4FV( params, ctx->Light.Material[f].Ambient );
 897          break;
 898       case GL_DIFFUSE:
 899          COPY_4FV( params, ctx->Light.Material[f].Diffuse );
 900          break;
 901       case GL_SPECULAR:
 902          COPY_4FV( params, ctx->Light.Material[f].Specular );
 903          break;
 904       case GL_EMISSION:
 905          COPY_4FV( params, ctx->Light.Material[f].Emission );
 906          break;
 907       case GL_SHININESS:
 908          *params = ctx->Light.Material[f].Shininess;
 909          break;
 910       case GL_COLOR_INDEXES:
 911          params[0] = ctx->Light.Material[f].AmbientIndex;
 912          params[1] = ctx->Light.Material[f].DiffuseIndex;
 913          params[2] = ctx->Light.Material[f].SpecularIndex;
 914          break;
 915       default:
 916          _mesa_error( ctx, GL_INVALID_ENUM, "glGetMaterialfv(pname)" );
 917    }
 918 }
 919
 920
 921
 922 void
 923 _mesa_GetMaterialiv( GLenum face, GLenum pname, GLint *params )
 924 {
 925    GET_CURRENT_CONTEXT(ctx);
 926    GLuint f;
 927    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx); /* update materials */
 928
 929    if (face==GL_FRONT) {
 930       f = 0;
 931    }
 932    else if (face==GL_BACK) {
 933       f = 1;
 934    }
 935    else {
 936       _mesa_error( ctx, GL_INVALID_ENUM, "glGetMaterialiv(face)" );
 937       return;
 938    }
 939    switch (pname) {
 940       case GL_AMBIENT:
 941          params[0] = FLOAT_TO_INT( ctx->Light.Material[f].Ambient[0] );
 942          params[1] = FLOAT_TO_INT( ctx->Light.Material[f].Ambient[1] );
 943          params[2] = FLOAT_TO_INT( ctx->Light.Material[f].Ambient[2] );
 944          params[3] = FLOAT_TO_INT( ctx->Light.Material[f].Ambient[3] );
 945          break;
 946       case GL_DIFFUSE:
 947          params[0] = FLOAT_TO_INT( ctx->Light.Material[f].Diffuse[0] );
 948          params[1] = FLOAT_TO_INT( ctx->Light.Material[f].Diffuse[1] );
 949          params[2] = FLOAT_TO_INT( ctx->Light.Material[f].Diffuse[2] );
 950          params[3] = FLOAT_TO_INT( ctx->Light.Material[f].Diffuse[3] );
 951          break;
 952       case GL_SPECULAR:
 953          params[0] = FLOAT_TO_INT( ctx->Light.Material[f].Specular[0] );
 954          params[1] = FLOAT_TO_INT( ctx->Light.Material[f].Specular[1] );
 955          params[2] = FLOAT_TO_INT( ctx->Light.Material[f].Specular[2] );
 956          params[3] = FLOAT_TO_INT( ctx->Light.Material[f].Specular[3] );
 957          break;
 958       case GL_EMISSION:
 959          params[0] = FLOAT_TO_INT( ctx->Light.Material[f].Emission[0] );
 960          params[1] = FLOAT_TO_INT( ctx->Light.Material[f].Emission[1] );
 961          params[2] = FLOAT_TO_INT( ctx->Light.Material[f].Emission[2] );
 962          params[3] = FLOAT_TO_INT( ctx->Light.Material[f].Emission[3] );
 963          break;
 964       case GL_SHININESS:
 965          *params = IROUND( ctx->Light.Material[f].Shininess );
 966          break;
 967       case GL_COLOR_INDEXES:
 968          params[0] = IROUND( ctx->Light.Material[f].AmbientIndex );
 969          params[1] = IROUND( ctx->Light.Material[f].DiffuseIndex );
 970          params[2] = IROUND( ctx->Light.Material[f].SpecularIndex );
 971          break;
 972       default:
 973          _mesa_error( ctx, GL_INVALID_ENUM, "glGetMaterialfv(pname)" );
 974    }
 975 }
 976
 977
 978
 979
 980 /**********************************************************************/
 981 /*****                  Lighting computation                      *****/
 982 /**********************************************************************/
 983
 984
 985 /*
 986  * Notes:
 987  *   When two-sided lighting is enabled we compute the color (or index)
 988  *   for both the front and back side of the primitive.  Then, when the
 989  *   orientation of the facet is later learned, we can determine which
 990  *   color (or index) to use for rendering.
 991  *
 992  *   KW: We now know orientation in advance and only shade for
 993  *       the side or sides which are actually required.
 994  *
 995  * Variables:
 996  *   n = normal vector
 997  *   V = vertex position
 998  *   P = light source position
 999  *   Pe = (0,0,0,1)
1000  *
1001  * Precomputed:
1002  *   IF P[3]==0 THEN
1003  *       // light at infinity
1004  *       IF local_viewer THEN
1005  *           _VP_inf_norm = unit vector from V to P      // Precompute
1006  *       ELSE
1007  *           // eye at infinity
1008  *           _h_inf_norm = Normalize( VP + <0,0,1> )     // Precompute
1009  *       ENDIF
1010  *   ENDIF
1011  *
1012  * Functions:
1013  *   Normalize( v ) = normalized vector v
1014  *   Magnitude( v ) = length of vector v
1015  */
1016
1017
1018
1019 /*
1020  * Whenever the spotlight exponent for a light changes we must call
1021  * this function to recompute the exponent lookup table.
1022  */
1023 void
1024 _mesa_invalidate_spot_exp_table( struct gl_light *l )
1025 {
1026    l->_SpotExpTable[0][0] = -1;
1027 }
1028
1029 static void validate_spot_exp_table( struct gl_light *l )
1030 {
1031    GLint i;
1032    GLdouble exponent = l->SpotExponent;
1033    GLdouble tmp = 0;
1034    GLint clamp = 0;
1035
1036    l->_SpotExpTable[0][0] = 0.0;
1037
1038    for (i = EXP_TABLE_SIZE - 1; i > 0 ;i--) {
1039       if (clamp == 0) {
1040          tmp = _mesa_pow(i / (GLdouble) (EXP_TABLE_SIZE - 1), exponent);
1041          if (tmp < FLT_MIN * 100.0) {
1042             tmp = 0.0;
1043             clamp = 1;
1044          }
1045       }
1046       l->_SpotExpTable[i][0] = (GLfloat) tmp;
1047    }
1048    for (i = 0; i < EXP_TABLE_SIZE - 1; i++) {
1049       l->_SpotExpTable[i][1] = (l->_SpotExpTable[i+1][0] -
1050                                 l->_SpotExpTable[i][0]);
1051    }
1052    l->_SpotExpTable[EXP_TABLE_SIZE-1][1] = 0.0;
1053 }
1054
1055
1056
1057
1058 /* Calculate a new shine table.  Doing this here saves a branch in
1059  * lighting, and the cost of doing it early may be partially offset
1060  * by keeping a MRU cache of shine tables for various shine values.
1061  */
1062 void
1063 _mesa_invalidate_shine_table( GLcontext *ctx, GLuint i )
1064 {
1065    if (ctx->_ShineTable[i])
1066       ctx->_ShineTable[i]->refcount--;
1067    ctx->_ShineTable[i] = 0;
1068 }
1069
1070 static void validate_shine_table( GLcontext *ctx, GLuint i, GLfloat shininess )
1071 {
1072    struct gl_shine_tab *list = ctx->_ShineTabList;
1073    struct gl_shine_tab *s;
1074
1075    foreach(s, list)
1076       if ( s->shininess == shininess )
1077          break;
1078
1079    if (s == list) {
1080       GLint j;
1081       GLfloat *m;
1082
1083       foreach(s, list)
1084          if (s->refcount == 0)
1085             break;
1086
1087       m = s->tab;
1088       m[0] = 0.0;
1089       if (shininess == 0.0) {
1090          for (j = 1 ; j <= SHINE_TABLE_SIZE ; j++)
1091             m[j] = 1.0;
1092       }
1093       else {
1094          for (j = 1 ; j < SHINE_TABLE_SIZE ; j++) {
1095             GLdouble t, x = j / (GLfloat) (SHINE_TABLE_SIZE - 1);
1096             if (x < 0.005) /* underflow check */
1097                x = 0.005;
1098             t = _mesa_pow(x, shininess);
1099             if (t > 1e-20)
1100                m[j] = (GLfloat) t;
1101             else
1102                m[j] = 0.0;
1103          }
1104          m[SHINE_TABLE_SIZE] = 1.0;
1105       }
1106
1107       s->shininess = shininess;
1108    }
1109
1110    if (ctx->_ShineTable[i])
1111       ctx->_ShineTable[i]->refcount--;
1112
1113    ctx->_ShineTable[i] = s;
1114    move_to_tail( list, s );
1115    s->refcount++;
1116 }
1117
1118 void
1119 _mesa_validate_all_lighting_tables( GLcontext *ctx )
1120 {
1121    GLint i;
1122    GLfloat shininess;
1123
1124    shininess = ctx->Light.Material[0].Shininess;
1125    if (!ctx->_ShineTable[0] || ctx->_ShineTable[0]->shininess != shininess)
1126       validate_shine_table( ctx, 0, shininess );
1127
1128    shininess = ctx->Light.Material[1].Shininess;
1129    if (!ctx->_ShineTable[1] || ctx->_ShineTable[1]->shininess != shininess)
1130       validate_shine_table( ctx, 1, shininess );
1131
1132    for (i = 0 ; i < MAX_LIGHTS ; i++)
1133       if (ctx->Light.Light[i]._SpotExpTable[0][0] == -1)
1134          validate_spot_exp_table( &ctx->Light.Light[i] );
1135 }
1136
1137
1138
1139
1140 /*
1141  * Examine current lighting parameters to determine if the optimized lighting
1142  * function can be used.
1143  * Also, precompute some lighting values such as the products of light
1144  * source and material ambient, diffuse and specular coefficients.
1145  */
1146 void
1147 _mesa_update_lighting( GLcontext *ctx )
1148 {
1149    struct gl_light *light;
1150    ctx->_NeedEyeCoords &= ~NEED_EYE_LIGHT;
1151    ctx->_NeedNormals &= ~NEED_NORMALS_LIGHT;
1152    ctx->Light._Flags = 0;
1153
1154    if (!ctx->Light.Enabled)
1155       return;
1156
1157    ctx->_NeedNormals |= NEED_NORMALS_LIGHT;
1158
1159    foreach(light, &ctx->Light.EnabledList) {
1160       ctx->Light._Flags |= light->_Flags;
1161    }
1162
1163    ctx->Light._NeedVertices =
1164       ((ctx->Light._Flags & (LIGHT_POSITIONAL|LIGHT_SPOT)) ||
1165        ctx->Light.Model.ColorControl == GL_SEPARATE_SPECULAR_COLOR ||
1166        ctx->Light.Model.LocalViewer);
1167
1168    if ((ctx->Light._Flags & LIGHT_POSITIONAL) ||
1169        ctx->Light.Model.LocalViewer)
1170       ctx->_NeedEyeCoords |= NEED_EYE_LIGHT;
1171
1172
1173    /* XXX: This test is overkill & needs to be fixed both for software and
1174     * hardware t&l drivers.  The above should be sufficient & should
1175     * be tested to verify this.
1176     */
1177    if (ctx->Light._NeedVertices)
1178       ctx->_NeedEyeCoords |= NEED_EYE_LIGHT;
1179
1180
1181    /* Precompute some shading values.  Although we reference
1182     * Light.Material here, we can get away without flushing
1183     * FLUSH_UPDATE_CURRENT, as when any outstanding material changes
1184     * are flushed, they will update the derived state at that time.
1185     */
1186    if (ctx->Visual.rgbMode) {
1187       GLuint sides = ctx->Light.Model.TwoSide ? 2 : 1;
1188       GLuint side;
1189       for (side=0; side < sides; side++) {
1190          struct gl_material *mat = &ctx->Light.Material[side];
1191
1192          COPY_3V(ctx->Light._BaseColor[side], mat->Emission);
1193          ACC_SCALE_3V(ctx->Light._BaseColor[side],
1194                       ctx->Light.Model.Ambient,
1195                       mat->Ambient);
1196       }
1197
1198       foreach (light, &ctx->Light.EnabledList) {
1199          for (side=0; side< sides; side++) {
1200             const struct gl_material *mat = &ctx->Light.Material[side];
1201             SCALE_3V( light->_MatDiffuse[side], light->Diffuse, mat->Diffuse );
1202             SCALE_3V( light->_MatAmbient[side], light->Ambient, mat->Ambient );
1203             SCALE_3V( light->_MatSpecular[side], light->Specular,
1204                       mat->Specular);
1205          }
1206       }
1207    }
1208    else {
1209       static const GLfloat ci[3] = { .30F, .59F, .11F };
1210       foreach(light, &ctx->Light.EnabledList) {
1211          light->_dli = DOT3(ci, light->Diffuse);
1212          light->_sli = DOT3(ci, light->Specular);
1213       }
1214    }
1215 }
1216
1217
1218 /* _NEW_MODELVIEW
1219  * _NEW_LIGHT
1220  * _TNL_NEW_NEED_EYE_COORDS
1221  *
1222  * Update on (_NEW_MODELVIEW | _NEW_LIGHT) when lighting is enabled.
1223  * Also update on lighting space changes.
1224  */
1225 void
1226 _mesa_compute_light_positions( GLcontext *ctx )
1227 {
1228    struct gl_light *light;
1229    static const GLfloat eye_z[3] = { 0, 0, 1 };
1230
1231    if (!ctx->Light.Enabled)
1232       return;
1233
1234    if (ctx->_NeedEyeCoords) {
1235       COPY_3V( ctx->_EyeZDir, eye_z );
1236    }
1237    else {
1238       TRANSFORM_NORMAL( ctx->_EyeZDir, eye_z, ctx->ModelviewMatrixStack.Top->m );
1239    }
1240
1241    foreach (light, &ctx->Light.EnabledList) {
1242
1243       if (ctx->_NeedEyeCoords) {
1244          COPY_4FV( light->_Position, light->EyePosition );
1245       }
1246       else {
1247          TRANSFORM_POINT( light->_Position, ctx->ModelviewMatrixStack.Top->inv,
1248                           light->EyePosition );
1249       }
1250
1251       if (!(light->_Flags & LIGHT_POSITIONAL)) {
1252          /* VP (VP) = Normalize( Position ) */
1253          COPY_3V( light->_VP_inf_norm, light->_Position );
1254          NORMALIZE_3FV( light->_VP_inf_norm );
1255
1256          if (!ctx->Light.Model.LocalViewer) {
1257             /* _h_inf_norm = Normalize( V_to_P + <0,0,1> ) */
1258             ADD_3V( light->_h_inf_norm, light->_VP_inf_norm, ctx->_EyeZDir);
1259             NORMALIZE_3FV( light->_h_inf_norm );
1260          }
1261          light->_VP_inf_spot_attenuation = 1.0;
1262       }
1263
1264       if (light->_Flags & LIGHT_SPOT) {
1265          if (ctx->_NeedEyeCoords) {
1266             COPY_3V( light->_NormDirection, light->EyeDirection );
1267          }
1268          else {
1269             TRANSFORM_NORMAL( light->_NormDirection,
1270                               light->EyeDirection,
1271                               ctx->ModelviewMatrixStack.Top->m);
1272          }
1273
1274          NORMALIZE_3FV( light->_NormDirection );
1275
1276          if (!(light->_Flags & LIGHT_POSITIONAL)) {
1277             GLfloat PV_dot_dir = - DOT3(light->_VP_inf_norm,
1278                                         light->_NormDirection);
1279
1280             if (PV_dot_dir > light->_CosCutoff) {
1281                double x = PV_dot_dir * (EXP_TABLE_SIZE-1);
1282                int k = (int) x;
1283                light->_VP_inf_spot_attenuation =
1284                   (GLfloat) (light->_SpotExpTable[k][0] +
1285                    (x-k)*light->_SpotExpTable[k][1]);
1286             }
1287             else {
1288                light->_VP_inf_spot_attenuation = 0;
1289             }
1290          }
1291       }
1292    }
1293 }