src/mesa/main/light.c

   1 /* $Id: light.c,v 1.6 1999/10/19 20:32:40 brianp Exp $ */
   2
   3 /*
   4  * Mesa 3-D graphics library
   5  * Version:  3.1
   6  *
   7  * Copyright (C) 1999  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
  29
  30
  31 #ifdef PC_HEADER
  32 #include "all.h"
  33 #else
  34 #include <float.h>
  35 #ifndef XFree86Server
  36 #include <assert.h>
  37 #include <float.h>
  38 #include <math.h>
  39 #include <stdlib.h>
  40 #else
  41 #include "GL/xf86glx.h"
  42 #endif
  43 #include <stdio.h>
  44 #include "context.h"
  45 #include "enums.h"
  46 #include "light.h"
  47 #include "macros.h"
  48 #include "matrix.h"
  49 #include "mmath.h"
  50 #include "simple_list.h"
  51 #include "types.h"
  52 #include "vb.h"
  53 #include "xform.h"
  54 #endif
  55
  56
  57
  58 void gl_ShadeModel( GLcontext *ctx, GLenum mode )
  59 {
  60    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx, "glShadeModel");
  61
  62    if (MESA_VERBOSE & VERBOSE_API)
  63       fprintf(stderr, "glShadeModel %s\n", gl_lookup_enum_by_nr(mode));
  64
  65
  66    switch (mode) {
  67    case GL_FLAT:
  68    case GL_SMOOTH:
  69       if (ctx->Light.ShadeModel!=mode) {
  70          ctx->Light.ShadeModel = mode;
  71          ctx->TriangleCaps ^= DD_FLATSHADE;
  72          ctx->NewState |= NEW_RASTER_OPS;
  73       }
  74       break;
  75    default:
  76       gl_error( ctx, GL_INVALID_ENUM, "glShadeModel" );
  77    }
  78
  79    if (ctx->Driver.ShadeModel)
  80       (*ctx->Driver.ShadeModel)( ctx, mode );
  81 }
  82
  83
  84
  85 void gl_Lightfv( GLcontext *ctx,
  86                  GLenum light, GLenum pname, const GLfloat *params,
  87                  GLint nparams )
  88 {
  89    GLint l;
  90
  91    (void) nparams;
  92
  93    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx, "glLight");
  94
  95    l = (GLint) (light - GL_LIGHT0);
  96
  97    if (l<0 || l>=MAX_LIGHTS) {
  98       gl_error( ctx, GL_INVALID_ENUM, "glLight" );
  99       return;
 100    }
 101
 102    switch (pname) {
 103       case GL_AMBIENT:
 104          COPY_4V( ctx->Light.Light[l].Ambient, params );
 105          break;
 106       case GL_DIFFUSE:
 107          COPY_4V( ctx->Light.Light[l].Diffuse, params );
 108          break;
 109       case GL_SPECULAR:
 110          COPY_4V( ctx->Light.Light[l].Specular, params );
 111          break;
 112       case GL_POSITION:
 113          /* transform position by ModelView matrix */
 114          TRANSFORM_POINT( ctx->Light.Light[l].EyePosition,
 115                           ctx->ModelView.m,
 116                           params );
 117          break;
 118       case GL_SPOT_DIRECTION:
 119          /* transform direction by inverse modelview */
 120          if (ctx->ModelView.flags & MAT_DIRTY_INVERSE) {
 121             gl_matrix_analyze( &ctx->ModelView );
 122          }
 123          TRANSFORM_NORMAL( ctx->Light.Light[l].EyeDirection,
 124                            params,
 125                            ctx->ModelView.inv );
 126          break;
 127       case GL_SPOT_EXPONENT:
 128          if (params[0]<0.0 || params[0]>128.0) {
 129             gl_error( ctx, GL_INVALID_VALUE, "glLight" );
 130             return;
 131          }
 132          if (ctx->Light.Light[l].SpotExponent != params[0]) {
 133             ctx->Light.Light[l].SpotExponent = params[0];
 134             gl_compute_spot_exp_table( &ctx->Light.Light[l] );
 135          }
 136          break;
 137       case GL_SPOT_CUTOFF:
 138          if ((params[0]<0.0 || params[0]>90.0) && params[0]!=180.0) {
 139             gl_error( ctx, GL_INVALID_VALUE, "glLight" );
 140             return;
 141          }
 142          ctx->Light.Light[l].SpotCutoff = params[0];
 143          ctx->Light.Light[l].CosCutoff = cos(params[0]*DEG2RAD);
 144          if (ctx->Light.Light[l].CosCutoff < 0)
 145             ctx->Light.Light[l].CosCutoff = 0;
 146          break;
 147       case GL_CONSTANT_ATTENUATION:
 148          if (params[0]<0.0) {
 149             gl_error( ctx, GL_INVALID_VALUE, "glLight" );
 150             return;
 151          }
 152          ctx->Light.Light[l].ConstantAttenuation = params[0];
 153          break;
 154       case GL_LINEAR_ATTENUATION:
 155          if (params[0]<0.0) {
 156             gl_error( ctx, GL_INVALID_VALUE, "glLight" );
 157             return;
 158          }
 159          ctx->Light.Light[l].LinearAttenuation = params[0];
 160          break;
 161       case GL_QUADRATIC_ATTENUATION:
 162          if (params[0]<0.0) {
 163             gl_error( ctx, GL_INVALID_VALUE, "glLight" );
 164             return;
 165          }
 166          ctx->Light.Light[l].QuadraticAttenuation = params[0];
 167          break;
 168       default:
 169          gl_error( ctx, GL_INVALID_ENUM, "glLight" );
 170          break;
 171    }
 172
 173    if (ctx->Driver.Lightfv)
 174       ctx->Driver.Lightfv( ctx, light, pname, params, nparams );
 175
 176    ctx->NewState |= NEW_LIGHTING;
 177 }
 178
 179
 180
 181 void gl_GetLightfv( GLcontext *ctx,
 182                     GLenum light, GLenum pname, GLfloat *params )
 183 {
 184    GLint l = (GLint) (light - GL_LIGHT0);
 185
 186    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx, "glGetLight");
 187
 188    if (l<0 || l>=MAX_LIGHTS) {
 189       gl_error( ctx, GL_INVALID_ENUM, "glGetLightfv" );
 190       return;
 191    }
 192
 193    switch (pname) {
 194       case GL_AMBIENT:
 195          COPY_4V( params, ctx->Light.Light[l].Ambient );
 196          break;
 197       case GL_DIFFUSE:
 198          COPY_4V( params, ctx->Light.Light[l].Diffuse );
 199          break;
 200       case GL_SPECULAR:
 201          COPY_4V( params, ctx->Light.Light[l].Specular );
 202          break;
 203       case GL_POSITION:
 204          COPY_4V( params, ctx->Light.Light[l].EyePosition );
 205          break;
 206       case GL_SPOT_DIRECTION:
 207          COPY_3V( params, ctx->Light.Light[l].EyeDirection );
 208          break;
 209       case GL_SPOT_EXPONENT:
 210          params[0] = ctx->Light.Light[l].SpotExponent;
 211          break;
 212       case GL_SPOT_CUTOFF:
 213          params[0] = ctx->Light.Light[l].SpotCutoff;
 214          break;
 215       case GL_CONSTANT_ATTENUATION:
 216          params[0] = ctx->Light.Light[l].ConstantAttenuation;
 217          break;
 218       case GL_LINEAR_ATTENUATION:
 219          params[0] = ctx->Light.Light[l].LinearAttenuation;
 220          break;
 221       case GL_QUADRATIC_ATTENUATION:
 222          params[0] = ctx->Light.Light[l].QuadraticAttenuation;
 223          break;
 224       default:
 225          gl_error( ctx, GL_INVALID_ENUM, "glGetLightfv" );
 226          break;
 227    }
 228 }
 229
 230
 231
 232 void gl_GetLightiv( GLcontext *ctx, GLenum light, GLenum pname, GLint *params )
 233 {
 234    GLint l = (GLint) (light - GL_LIGHT0);
 235
 236    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx, "glGetLight");
 237
 238    if (l<0 || l>=MAX_LIGHTS) {
 239       gl_error( ctx, GL_INVALID_ENUM, "glGetLightiv" );
 240       return;
 241    }
 242
 243    switch (pname) {
 244       case GL_AMBIENT:
 245          params[0] = FLOAT_TO_INT(ctx->Light.Light[l].Ambient[0]);
 246          params[1] = FLOAT_TO_INT(ctx->Light.Light[l].Ambient[1]);
 247          params[2] = FLOAT_TO_INT(ctx->Light.Light[l].Ambient[2]);
 248          params[3] = FLOAT_TO_INT(ctx->Light.Light[l].Ambient[3]);
 249          break;
 250       case GL_DIFFUSE:
 251          params[0] = FLOAT_TO_INT(ctx->Light.Light[l].Diffuse[0]);
 252          params[1] = FLOAT_TO_INT(ctx->Light.Light[l].Diffuse[1]);
 253          params[2] = FLOAT_TO_INT(ctx->Light.Light[l].Diffuse[2]);
 254          params[3] = FLOAT_TO_INT(ctx->Light.Light[l].Diffuse[3]);
 255          break;
 256       case GL_SPECULAR:
 257          params[0] = FLOAT_TO_INT(ctx->Light.Light[l].Specular[0]);
 258          params[1] = FLOAT_TO_INT(ctx->Light.Light[l].Specular[1]);
 259          params[2] = FLOAT_TO_INT(ctx->Light.Light[l].Specular[2]);
 260          params[3] = FLOAT_TO_INT(ctx->Light.Light[l].Specular[3]);
 261          break;
 262       case GL_POSITION:
 263          params[0] = (GLint) ctx->Light.Light[l].EyePosition[0];
 264          params[1] = (GLint) ctx->Light.Light[l].EyePosition[1];
 265          params[2] = (GLint) ctx->Light.Light[l].EyePosition[2];
 266          params[3] = (GLint) ctx->Light.Light[l].EyePosition[3];
 267          break;
 268       case GL_SPOT_DIRECTION:
 269          params[0] = (GLint) ctx->Light.Light[l].EyeDirection[0];
 270          params[1] = (GLint) ctx->Light.Light[l].EyeDirection[1];
 271          params[2] = (GLint) ctx->Light.Light[l].EyeDirection[2];
 272          break;
 273       case GL_SPOT_EXPONENT:
 274          params[0] = (GLint) ctx->Light.Light[l].SpotExponent;
 275          break;
 276       case GL_SPOT_CUTOFF:
 277          params[0] = (GLint) ctx->Light.Light[l].SpotCutoff;
 278          break;
 279       case GL_CONSTANT_ATTENUATION:
 280          params[0] = (GLint) ctx->Light.Light[l].ConstantAttenuation;
 281          break;
 282       case GL_LINEAR_ATTENUATION:
 283          params[0] = (GLint) ctx->Light.Light[l].LinearAttenuation;
 284          break;
 285       case GL_QUADRATIC_ATTENUATION:
 286          params[0] = (GLint) ctx->Light.Light[l].QuadraticAttenuation;
 287          break;
 288       default:
 289          gl_error( ctx, GL_INVALID_ENUM, "glGetLightiv" );
 290          break;
 291    }
 292 }
 293
 294
 295
 296 /**********************************************************************/
 297 /***                        Light Model                             ***/
 298 /**********************************************************************/
 299
 300
 301 void gl_LightModelfv( GLcontext *ctx, GLenum pname, const GLfloat *params )
 302 {
 303    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx, "glLightModel");
 304
 305    switch (pname) {
 306       case GL_LIGHT_MODEL_AMBIENT:
 307          COPY_4V( ctx->Light.Model.Ambient, params );
 308          break;
 309       case GL_LIGHT_MODEL_LOCAL_VIEWER:
 310          if (params[0]==0.0)
 311             ctx->Light.Model.LocalViewer = GL_FALSE;
 312          else
 313             ctx->Light.Model.LocalViewer = GL_TRUE;
 314          break;
 315       case GL_LIGHT_MODEL_TWO_SIDE:
 316          if (params[0]==0.0)
 317             ctx->Light.Model.TwoSide = GL_FALSE;
 318          else
 319             ctx->Light.Model.TwoSide = GL_TRUE;
 320          break;
 321       case GL_LIGHT_MODEL_COLOR_CONTROL:
 322          if (params[0] == (GLfloat) GL_SINGLE_COLOR) {
 323             ctx->Light.Model.ColorControl = GL_SINGLE_COLOR;
 324             ctx->TriangleCaps &= ~DD_SEPERATE_SPECULAR;
 325          }
 326          else if (params[0] == (GLfloat) GL_SEPARATE_SPECULAR_COLOR) {
 327             ctx->Light.Model.ColorControl = GL_SEPARATE_SPECULAR_COLOR;
 328             ctx->TriangleCaps |= DD_SEPERATE_SPECULAR;
 329          }
 330          else {
 331             gl_error( ctx, GL_INVALID_ENUM, "glLightModel(param)" );
 332          }
 333          ctx->NewState |= NEW_RASTER_OPS;
 334          break;
 335       default:
 336          gl_error( ctx, GL_INVALID_ENUM, "glLightModel" );
 337          break;
 338    }
 339
 340    if (ctx->Driver.LightModelfv)
 341       ctx->Driver.LightModelfv( ctx, pname, params );
 342
 343    ctx->NewState |= NEW_LIGHTING;
 344 }
 345
 346
 347
 348
 349 /********** MATERIAL **********/
 350
 351
 352 /*
 353  * Given a face and pname value (ala glColorMaterial), compute a bitmask
 354  * of the targeted material values.
 355  */
 356 GLuint gl_material_bitmask( GLcontext *ctx, GLenum face, GLenum pname,
 357                             GLuint legal,
 358                             const char *where )
 359 {
 360    GLuint bitmask = 0;
 361
 362    /* Make a bitmask indicating what material attribute(s) we're updating */
 363    switch (pname) {
 364       case GL_EMISSION:
 365          bitmask |= FRONT_EMISSION_BIT | BACK_EMISSION_BIT;
 366          break;
 367       case GL_AMBIENT:
 368          bitmask |= FRONT_AMBIENT_BIT | BACK_AMBIENT_BIT;
 369          break;
 370       case GL_DIFFUSE:
 371          bitmask |= FRONT_DIFFUSE_BIT | BACK_DIFFUSE_BIT;
 372          break;
 373       case GL_SPECULAR:
 374          bitmask |= FRONT_SPECULAR_BIT | BACK_SPECULAR_BIT;
 375          break;
 376       case GL_SHININESS:
 377          bitmask |= FRONT_SHININESS_BIT | BACK_SHININESS_BIT;
 378          break;
 379       case GL_AMBIENT_AND_DIFFUSE:
 380          bitmask |= FRONT_AMBIENT_BIT | BACK_AMBIENT_BIT;
 381          bitmask |= FRONT_DIFFUSE_BIT | BACK_DIFFUSE_BIT;
 382          break;
 383       case GL_COLOR_INDEXES:
 384          bitmask |= FRONT_INDEXES_BIT  | BACK_INDEXES_BIT;
 385          break;
 386       default:
 387          gl_error( ctx, GL_INVALID_ENUM, where );
 388          return 0;
 389    }
 390
 391    if (face==GL_FRONT) {
 392       bitmask &= FRONT_MATERIAL_BITS;
 393    }
 394    else if (face==GL_BACK) {
 395       bitmask &= BACK_MATERIAL_BITS;
 396    }
 397    else if (face != GL_FRONT_AND_BACK) {
 398       gl_error( ctx, GL_INVALID_ENUM, where );
 399       return 0;
 400    }
 401
 402    if (bitmask & ~legal) {
 403       gl_error( ctx, GL_INVALID_ENUM, where );
 404       return 0;
 405    }
 406
 407    return bitmask;
 408 }
 409
 410
 411
 412
 413
 414
 415 /*
 416  * Check if the global material has to be updated with info that was
 417  * associated with a vertex via glMaterial.
 418  * This function is used when any material values get changed between
 419  * glBegin/glEnd either by calling glMaterial() or by calling glColor()
 420  * when GL_COLOR_MATERIAL is enabled.
 421  *
 422  * KW: Added code here to keep the precomputed variables uptodate.
 423  *     This means we can use the faster shade functions when using
 424  *     GL_COLOR_MATERIAL, and we can also now use the precomputed
 425  *     values in the slower shading functions, which further offsets
 426  *     the cost of doing this here.
 427  */
 428 void gl_update_material( GLcontext *ctx,
 429                          struct gl_material *src,
 430                          GLuint bitmask )
 431 {
 432    struct gl_light *light, *list = &ctx->Light.EnabledList;
 433    GLfloat tmp[4];
 434
 435    if (ctx->Light.ColorMaterialEnabled)
 436       bitmask &= ~ctx->Light.ColorMaterialBitmask;
 437
 438    if (!bitmask)
 439       return;
 440
 441    if (bitmask & FRONT_AMBIENT_BIT) {
 442       struct gl_material *mat = &ctx->Light.Material[0];
 443       SUB_3V( tmp, src[0].Ambient, mat->Ambient );
 444       ACC_SCALE_3V( ctx->Light.BaseColor[0], ctx->Light.Model.Ambient, tmp);
 445       foreach (light, list) {
 446          ACC_SCALE_3V( ctx->Light.BaseColor[0], light->Ambient, tmp );
 447       }
 448       COPY_4FV( mat->Ambient, src[0].Ambient );
 449    }
 450    if (bitmask & BACK_AMBIENT_BIT) {
 451       struct gl_material *mat = &ctx->Light.Material[1];
 452       SUB_3V( tmp, src[1].Ambient, mat->Ambient );
 453       ACC_SCALE_3V( ctx->Light.BaseColor[1], ctx->Light.Model.Ambient, tmp);
 454       foreach (light, list) {
 455          ACC_SCALE_3V( ctx->Light.BaseColor[0], light->Ambient, tmp );
 456       }
 457       COPY_4FV( mat->Ambient, src[1].Ambient );
 458    }
 459    if (bitmask & FRONT_DIFFUSE_BIT) {
 460       struct gl_material *mat = &ctx->Light.Material[0];
 461       SUB_3V( tmp, src[0].Diffuse, mat->Diffuse );
 462       foreach (light, list) {
 463          ACC_SCALE_3V( light->MatDiffuse[0], light->Diffuse, tmp );
 464       }
 465       COPY_4FV( mat->Diffuse, src[0].Diffuse );
 466       FLOAT_COLOR_TO_UBYTE_COLOR(ctx->Light.BaseAlpha[0], mat->Diffuse[3]);
 467    }
 468    if (bitmask & BACK_DIFFUSE_BIT) {
 469       struct gl_material *mat = &ctx->Light.Material[1];
 470       SUB_3V( tmp, src[1].Diffuse, mat->Diffuse );
 471       foreach (light, list) {
 472          ACC_SCALE_3V( light->MatDiffuse[1], light->Diffuse, tmp );
 473       }
 474       COPY_4FV( mat->Diffuse, src[1].Diffuse );
 475       FLOAT_COLOR_TO_UBYTE_COLOR(ctx->Light.BaseAlpha[1], mat->Diffuse[3]);
 476    }
 477    if (bitmask & FRONT_SPECULAR_BIT) {
 478       struct gl_material *mat = &ctx->Light.Material[0];
 479       SUB_3V( tmp, src[0].Specular, mat->Specular );
 480       foreach (light, list) {
 481          if (light->Flags & LIGHT_SPECULAR) {
 482             ACC_SCALE_3V( light->MatSpecular[0], light->Specular, tmp );
 483             light->IsMatSpecular[0] =
 484                (LEN_SQUARED_3FV(light->MatSpecular[0]) > 1e-16);
 485          }
 486       }
 487       COPY_4FV( mat->Specular, src[0].Specular );
 488    }
 489    if (bitmask & BACK_SPECULAR_BIT) {
 490       struct gl_material *mat = &ctx->Light.Material[1];
 491       SUB_3V( tmp, src[1].Specular, mat->Specular );
 492       foreach (light, list) {
 493          if (light->Flags & LIGHT_SPECULAR) {
 494             ACC_SCALE_3V( light->MatSpecular[1], light->Specular, tmp );
 495             light->IsMatSpecular[1] =
 496                (LEN_SQUARED_3FV(light->MatSpecular[1]) > 1e-16);
 497          }
 498       }
 499       COPY_4FV( mat->Specular, src[1].Specular );
 500    }
 501    if (bitmask & FRONT_EMISSION_BIT) {
 502       struct gl_material *mat = &ctx->Light.Material[0];
 503       SUB_3V( tmp, src[0].Emission, mat->Emission );
 504       ACC_3V( ctx->Light.BaseColor[0], tmp );
 505       COPY_4FV( mat->Emission, src[0].Emission );
 506    }
 507    if (bitmask & BACK_EMISSION_BIT) {
 508       struct gl_material *mat = &ctx->Light.Material[1];
 509       SUB_3V( tmp, src[1].Emission, mat->Emission );
 510       ACC_3V( ctx->Light.BaseColor[1], tmp );
 511       COPY_4FV( mat->Emission, src[1].Emission );
 512    }
 513    if (bitmask & FRONT_SHININESS_BIT) {
 514       GLfloat shininess = ctx->Light.Material[0].Shininess = src[0].Shininess;
 515       gl_compute_shine_table( ctx, 0, shininess );
 516       gl_compute_shine_table( ctx, 2, shininess * .5 );
 517    }
 518    if (bitmask & BACK_SHININESS_BIT) {
 519       GLfloat shininess = ctx->Light.Material[1].Shininess = src[1].Shininess;
 520       gl_compute_shine_table( ctx, 1, shininess );
 521       gl_compute_shine_table( ctx, 3, shininess * .5 );
 522    }
 523    if (bitmask & FRONT_INDEXES_BIT) {
 524       ctx->Light.Material[0].AmbientIndex = src[0].AmbientIndex;
 525       ctx->Light.Material[0].DiffuseIndex = src[0].DiffuseIndex;
 526       ctx->Light.Material[0].SpecularIndex = src[0].SpecularIndex;
 527    }
 528    if (bitmask & BACK_INDEXES_BIT) {
 529       ctx->Light.Material[1].AmbientIndex = src[1].AmbientIndex;
 530       ctx->Light.Material[1].DiffuseIndex = src[1].DiffuseIndex;
 531       ctx->Light.Material[1].SpecularIndex = src[1].SpecularIndex;
 532    }
 533
 534 }
 535
 536
 537
 538
 539
 540
 541 void gl_update_color_material( GLcontext *ctx,
 542                                const GLubyte rgba[4] )
 543 {
 544    struct gl_light *light, *list = &ctx->Light.EnabledList;
 545    GLuint bitmask = ctx->Light.ColorMaterialBitmask;
 546    GLfloat tmp[4], color[4];
 547
 548    UBYTE_RGBA_TO_FLOAT_RGBA( color, rgba );
 549
 550    if (bitmask & FRONT_AMBIENT_BIT) {
 551       struct gl_material *mat = &ctx->Light.Material[0];
 552       SUB_3V( tmp, color, mat->Ambient );
 553       ACC_SCALE_3V( ctx->Light.BaseColor[0], ctx->Light.Model.Ambient, tmp);
 554       foreach (light, list) {
 555          ACC_SCALE_3V( ctx->Light.BaseColor[0], light->Ambient, tmp );
 556       }
 557       COPY_4FV( mat->Ambient, color );
 558    }
 559
 560    if (bitmask & BACK_AMBIENT_BIT) {
 561       struct gl_material *mat = &ctx->Light.Material[1];
 562       SUB_3V( tmp, color, mat->Ambient );
 563       ACC_SCALE_3V( ctx->Light.BaseColor[1], ctx->Light.Model.Ambient, tmp);
 564       foreach (light, list) {
 565          ACC_SCALE_3V( ctx->Light.BaseColor[0], light->Ambient, tmp );
 566       }
 567       COPY_4FV( mat->Ambient, color );
 568    }
 569
 570    if (bitmask & FRONT_DIFFUSE_BIT) {
 571       struct gl_material *mat = &ctx->Light.Material[0];
 572       SUB_3V( tmp, color, mat->Diffuse );
 573       foreach (light, list) {
 574          ACC_SCALE_3V( light->MatDiffuse[0], light->Diffuse, tmp );
 575       }
 576       COPY_4FV( mat->Diffuse, color );
 577       FLOAT_COLOR_TO_UBYTE_COLOR(ctx->Light.BaseAlpha[0], mat->Diffuse[3]);
 578    }
 579
 580    if (bitmask & BACK_DIFFUSE_BIT) {
 581       struct gl_material *mat = &ctx->Light.Material[1];
 582       SUB_3V( tmp, color, mat->Diffuse );
 583       foreach (light, list) {
 584          ACC_SCALE_3V( light->MatDiffuse[1], light->Diffuse, tmp );
 585       }
 586       COPY_4FV( mat->Diffuse, color );
 587       FLOAT_COLOR_TO_UBYTE_COLOR(ctx->Light.BaseAlpha[1], mat->Diffuse[3]);
 588    }
 589
 590    if (bitmask & FRONT_SPECULAR_BIT) {
 591       struct gl_material *mat = &ctx->Light.Material[0];
 592       SUB_3V( tmp, color, mat->Specular );
 593       foreach (light, list) {
 594          if (light->Flags & LIGHT_SPECULAR) {
 595             ACC_SCALE_3V( light->MatSpecular[0], light->Specular, tmp );
 596             light->IsMatSpecular[0] =
 597                (LEN_SQUARED_3FV(light->MatSpecular[0]) > 1e-16);
 598          }
 599       }
 600       COPY_4FV( mat->Specular, color );
 601    }
 602    if (bitmask & BACK_SPECULAR_BIT) {
 603       struct gl_material *mat = &ctx->Light.Material[1];
 604       SUB_3V( tmp, color, mat->Specular );
 605       foreach (light, list) {
 606          if (light->Flags & LIGHT_SPECULAR) {
 607             ACC_SCALE_3V( light->MatSpecular[1], light->Specular, tmp );
 608             light->IsMatSpecular[1] =
 609                (LEN_SQUARED_3FV(light->MatSpecular[1]) > 1e-16);
 610          }
 611       }
 612       COPY_4FV( mat->Specular, color );
 613    }
 614    if (bitmask & FRONT_EMISSION_BIT) {
 615       struct gl_material *mat = &ctx->Light.Material[0];
 616       SUB_3V( tmp, color, mat->Emission );
 617       ACC_3V( ctx->Light.BaseColor[0], tmp );
 618       COPY_4FV( mat->Emission, color );
 619    }
 620    if (bitmask & BACK_EMISSION_BIT) {
 621       struct gl_material *mat = &ctx->Light.Material[1];
 622       SUB_3V( tmp, color, mat->Emission );
 623       ACC_3V( ctx->Light.BaseColor[1], tmp );
 624       COPY_4FV( mat->Emission, color );
 625    }
 626 }
 627
 628
 629
 630
 631 void gl_ColorMaterial( GLcontext *ctx, GLenum face, GLenum mode )
 632 {
 633    GLuint bitmask;
 634    GLuint legal = (FRONT_EMISSION_BIT | BACK_EMISSION_BIT |
 635                    FRONT_SPECULAR_BIT | BACK_SPECULAR_BIT |
 636                    FRONT_DIFFUSE_BIT  | BACK_DIFFUSE_BIT  |
 637                    FRONT_AMBIENT_BIT  | BACK_AMBIENT_BIT);
 638
 639    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx, "glColorMaterial");
 640
 641    bitmask = gl_material_bitmask( ctx, face, mode, legal, "glColorMaterial" );
 642
 643    if (bitmask != 0) {
 644       ctx->Light.ColorMaterialBitmask = bitmask;
 645       ctx->Light.ColorMaterialFace = face;
 646       ctx->Light.ColorMaterialMode = mode;
 647    }
 648 }
 649
 650
 651
 652 /* KW:  This is now called directly (ie by name) from the glMaterial*
 653  *      API functions.
 654  */
 655 void gl_Materialfv( GLcontext *ctx,
 656                     GLenum face, GLenum pname, const GLfloat *params )
 657 {
 658    struct immediate *IM;
 659    struct gl_material *mat;
 660    GLuint bitmask;
 661    GLuint count;
 662
 663    bitmask = gl_material_bitmask( ctx, face, pname, ~0, "gl_Materialfv" );
 664    if (bitmask == 0)
 665       return;
 666
 667    IM = ctx->input;
 668    count = IM->Count;
 669
 670    if (!IM->Material) {
 671       IM->Material =
 672          (struct gl_material (*)[2]) MALLOC( sizeof(struct gl_material) *
 673                                              VB_SIZE * 2 );
 674       IM->MaterialMask = (GLuint *) MALLOC( sizeof(GLuint) * VB_SIZE );
 675    }
 676
 677
 678    if (!(IM->Flag[count] & VERT_MATERIAL)) {
 679       IM->Flag[count] |= VERT_MATERIAL;
 680       IM->MaterialMask[count] = 0;
 681    }
 682
 683
 684    IM->MaterialMask[count] |= bitmask;
 685    mat = IM->Material[count];
 686
 687    if (bitmask & FRONT_AMBIENT_BIT) {
 688       COPY_4FV( mat[0].Ambient, params );
 689    }
 690    if (bitmask & BACK_AMBIENT_BIT) {
 691       COPY_4FV( mat[1].Ambient, params );
 692    }
 693    if (bitmask & FRONT_DIFFUSE_BIT) {
 694       COPY_4FV( mat[0].Diffuse, params );
 695    }
 696    if (bitmask & BACK_DIFFUSE_BIT) {
 697       COPY_4FV( mat[1].Diffuse, params );
 698    }
 699    if (bitmask & FRONT_SPECULAR_BIT) {
 700       COPY_4FV( mat[0].Specular, params );
 701    }
 702    if (bitmask & BACK_SPECULAR_BIT) {
 703       COPY_4FV( mat[1].Specular, params );
 704    }
 705    if (bitmask & FRONT_EMISSION_BIT) {
 706       COPY_4FV( mat[0].Emission, params );
 707    }
 708    if (bitmask & BACK_EMISSION_BIT) {
 709       COPY_4FV( mat[1].Emission, params );
 710    }
 711    if (bitmask & FRONT_SHININESS_BIT) {
 712       GLfloat shininess = CLAMP( params[0], 0.0F, 128.0F );
 713       mat[0].Shininess = shininess;
 714    }
 715    if (bitmask & BACK_SHININESS_BIT) {
 716       GLfloat shininess = CLAMP( params[0], 0.0F, 128.0F );
 717       mat[1].Shininess = shininess;
 718    }
 719    if (bitmask & FRONT_INDEXES_BIT) {
 720       mat[0].AmbientIndex = params[0];
 721       mat[0].DiffuseIndex = params[1];
 722       mat[0].SpecularIndex = params[2];
 723    }
 724    if (bitmask & BACK_INDEXES_BIT) {
 725       mat[1].AmbientIndex = params[0];
 726       mat[1].DiffuseIndex = params[1];
 727       mat[1].SpecularIndex = params[2];
 728    }
 729 }
 730
 731
 732
 733
 734 void gl_GetMaterialfv( GLcontext *ctx,
 735                        GLenum face, GLenum pname, GLfloat *params )
 736 {
 737    GLuint f;
 738
 739    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx, "glGetMaterialfv");
 740
 741    if (face==GL_FRONT) {
 742       f = 0;
 743    }
 744    else if (face==GL_BACK) {
 745       f = 1;
 746    }
 747    else {
 748       gl_error( ctx, GL_INVALID_ENUM, "glGetMaterialfv(face)" );
 749       return;
 750    }
 751    switch (pname) {
 752       case GL_AMBIENT:
 753          COPY_4FV( params, ctx->Light.Material[f].Ambient );
 754          break;
 755       case GL_DIFFUSE:
 756          COPY_4FV( params, ctx->Light.Material[f].Diffuse );
 757          break;
 758       case GL_SPECULAR:
 759          COPY_4FV( params, ctx->Light.Material[f].Specular );
 760          break;
 761       case GL_EMISSION:
 762          COPY_4FV( params, ctx->Light.Material[f].Emission );
 763          break;
 764       case GL_SHININESS:
 765          *params = ctx->Light.Material[f].Shininess;
 766          break;
 767       case GL_COLOR_INDEXES:
 768          params[0] = ctx->Light.Material[f].AmbientIndex;
 769          params[1] = ctx->Light.Material[f].DiffuseIndex;
 770          params[2] = ctx->Light.Material[f].SpecularIndex;
 771          break;
 772       default:
 773          gl_error( ctx, GL_INVALID_ENUM, "glGetMaterialfv(pname)" );
 774    }
 775 }
 776
 777
 778
 779 void gl_GetMaterialiv( GLcontext *ctx,
 780                        GLenum face, GLenum pname, GLint *params )
 781 {
 782    GLuint f;
 783
 784    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx, "glGetMaterialiv");
 785
 786    if (face==GL_FRONT) {
 787       f = 0;
 788    }
 789    else if (face==GL_BACK) {
 790       f = 1;
 791    }
 792    else {
 793       gl_error( ctx, GL_INVALID_ENUM, "glGetMaterialiv(face)" );
 794       return;
 795    }
 796    switch (pname) {
 797       case GL_AMBIENT:
 798          params[0] = FLOAT_TO_INT( ctx->Light.Material[f].Ambient[0] );
 799          params[1] = FLOAT_TO_INT( ctx->Light.Material[f].Ambient[1] );
 800          params[2] = FLOAT_TO_INT( ctx->Light.Material[f].Ambient[2] );
 801          params[3] = FLOAT_TO_INT( ctx->Light.Material[f].Ambient[3] );
 802          break;
 803       case GL_DIFFUSE:
 804          params[0] = FLOAT_TO_INT( ctx->Light.Material[f].Diffuse[0] );
 805          params[1] = FLOAT_TO_INT( ctx->Light.Material[f].Diffuse[1] );
 806          params[2] = FLOAT_TO_INT( ctx->Light.Material[f].Diffuse[2] );
 807          params[3] = FLOAT_TO_INT( ctx->Light.Material[f].Diffuse[3] );
 808          break;
 809       case GL_SPECULAR:
 810          params[0] = FLOAT_TO_INT( ctx->Light.Material[f].Specular[0] );
 811          params[1] = FLOAT_TO_INT( ctx->Light.Material[f].Specular[1] );
 812          params[2] = FLOAT_TO_INT( ctx->Light.Material[f].Specular[2] );
 813          params[3] = FLOAT_TO_INT( ctx->Light.Material[f].Specular[3] );
 814          break;
 815       case GL_EMISSION:
 816          params[0] = FLOAT_TO_INT( ctx->Light.Material[f].Emission[0] );
 817          params[1] = FLOAT_TO_INT( ctx->Light.Material[f].Emission[1] );
 818          params[2] = FLOAT_TO_INT( ctx->Light.Material[f].Emission[2] );
 819          params[3] = FLOAT_TO_INT( ctx->Light.Material[f].Emission[3] );
 820          break;
 821       case GL_SHININESS:
 822          *params = ROUNDF( ctx->Light.Material[f].Shininess );
 823          break;
 824       case GL_COLOR_INDEXES:
 825          params[0] = ROUNDF( ctx->Light.Material[f].AmbientIndex );
 826          params[1] = ROUNDF( ctx->Light.Material[f].DiffuseIndex );
 827          params[2] = ROUNDF( ctx->Light.Material[f].SpecularIndex );
 828          break;
 829       default:
 830          gl_error( ctx, GL_INVALID_ENUM, "glGetMaterialfv(pname)" );
 831    }
 832 }
 833
 834
 835
 836
 837 /**********************************************************************/
 838 /*****                  Lighting computation                      *****/
 839 /**********************************************************************/
 840
 841
 842 /*
 843  * Notes:
 844  *   When two-sided lighting is enabled we compute the color (or index)
 845  *   for both the front and back side of the primitive.  Then, when the
 846  *   orientation of the facet is later learned, we can determine which
 847  *   color (or index) to use for rendering.
 848  *
 849  *   KW: We now know orientation in advance and only shade for
 850  *       the side or sides which are actually required.
 851  *
 852  * Variables:
 853  *   n = normal vector
 854  *   V = vertex position
 855  *   P = light source position
 856  *   Pe = (0,0,0,1)
 857  *
 858  * Precomputed:
 859  *   IF P[3]==0 THEN
 860  *       // light at infinity
 861  *       IF local_viewer THEN
 862  *           VP_inf_norm = unit vector from V to P      // Precompute
 863  *       ELSE
 864  *           // eye at infinity
 865  *           h_inf_norm = Normalize( VP + <0,0,1> )     // Precompute
 866  *       ENDIF
 867  *   ENDIF
 868  *
 869  * Functions:
 870  *   Normalize( v ) = normalized vector v
 871  *   Magnitude( v ) = length of vector v
 872  */
 873
 874
 875
 876 /*
 877  * Whenever the spotlight exponent for a light changes we must call
 878  * this function to recompute the exponent lookup table.
 879  */
 880 void gl_compute_spot_exp_table( struct gl_light *l )
 881 {
 882    int i;
 883    double exponent = l->SpotExponent;
 884    double tmp = 0;
 885    int clamp = 0;
 886
 887    l->SpotExpTable[0][0] = 0.0;
 888
 889    for (i=EXP_TABLE_SIZE-1;i>0;i--) {
 890       if (clamp == 0) {
 891          tmp = pow(i/(double)(EXP_TABLE_SIZE-1), exponent);
 892          if (tmp < FLT_MIN*100.0) {
 893             tmp = 0.0;
 894             clamp = 1;
 895          }
 896       }
 897       l->SpotExpTable[i][0] = tmp;
 898    }
 899    for (i=0;i<EXP_TABLE_SIZE-1;i++) {
 900       l->SpotExpTable[i][1] = l->SpotExpTable[i+1][0] - l->SpotExpTable[i][0];
 901    }
 902    l->SpotExpTable[EXP_TABLE_SIZE-1][1] = 0.0;
 903 }
 904
 905
 906
 907
 908 /* Calculate a new shine table.  Doing this here saves a branch in
 909  * lighting, and the cost of doing it early may be partially offset
 910  * by keeping a MRU cache of shine tables for various shine values.
 911  */
 912 static void compute_shine_table( struct gl_shine_tab *tab, GLfloat shininess )
 913 {
 914    int i;
 915    GLfloat *m = tab->tab;
 916
 917    m[0] = 0;
 918    if (shininess == 0) {
 919       for (i = 1 ; i <= SHINE_TABLE_SIZE ; i++)
 920          m[i] = 1;
 921    } else {
 922       for (i = 1 ; i <= SHINE_TABLE_SIZE ; i++) {
 923          double t = pow( i/(GLfloat)SHINE_TABLE_SIZE, shininess );
 924          m[i] = 0;
 925          if (t > 1e-20) m[i] = t;
 926       }
 927    }
 928
 929    tab->shininess = shininess;
 930 }
 931
 932 #define DISTSQR(a,b) ((a-b)*(a-b))
 933
 934 void gl_compute_shine_table( GLcontext *ctx, GLuint i, GLfloat shininess )
 935 {
 936    struct gl_shine_tab *list = ctx->ShineTabList;
 937    struct gl_shine_tab *s;
 938
 939    foreach(s, list)
 940       if ( DISTSQR(s->shininess, shininess) < 1e-4 )
 941          break;
 942
 943    if (s == list)
 944    {
 945       foreach(s, list)
 946          if (s->refcount == 0) break;
 947
 948       compute_shine_table( s, shininess );
 949    }
 950
 951    ctx->ShineTable[i]->refcount--;
 952    ctx->ShineTable[i] = s;
 953    move_to_tail( list, s );
 954    s->refcount++;
 955 }
 956
 957
 958
 959
 960 void gl_reinit_light_attrib( GLcontext *ctx, struct gl_light_attrib *l )
 961 {
 962    GLuint i;
 963
 964    if (ctx->ShineTable[0]->shininess != l->Material[0].Shininess) {
 965       gl_compute_shine_table( ctx, 0, l->Material[0].Shininess );
 966       gl_compute_shine_table( ctx, 2, l->Material[0].Shininess * .5 );
 967    }
 968
 969    if (ctx->ShineTable[1]->shininess != l->Material[1].Shininess) {
 970       gl_compute_shine_table( ctx, 1, l->Material[1].Shininess );
 971       gl_compute_shine_table( ctx, 3, l->Material[1].Shininess * .5 );
 972    }
 973
 974    make_empty_list( &l->EnabledList );
 975    for (i = 0 ; i < MAX_LIGHTS ; i++) {
 976       if (l->Light[i].Enabled)
 977          insert_at_tail( &l->EnabledList, &l->Light[i] );
 978    }
 979 }
 980
 981
 982
 983 /*
 984  * Examine current lighting parameters to determine if the optimized lighting
 985  * function can be used.
 986  * Also, precompute some lighting values such as the products of light
 987  * source and material ambient, diffuse and specular coefficients.
 988  */
 989 void gl_update_lighting( GLcontext *ctx )
 990 {
 991    struct gl_light *light;
 992
 993    ctx->Light.Flags = 0;
 994
 995    foreach(light, &ctx->Light.EnabledList) {
 996
 997       light->Flags = 0;
 998
 999       if (light->EyePosition[3] != 0.0F)
1000          light->Flags |= LIGHT_POSITIONAL;
1001
1002       if (LEN_SQUARED_3FV(light->Specular) > 1e-16)
1003          light->Flags |= LIGHT_SPECULAR;
1004
1005       if (light->SpotCutoff != 180.0F)
1006          light->Flags |= LIGHT_SPOT;
1007
1008       ctx->Light.Flags |= light->Flags;
1009    }
1010
1011    ctx->Light.NeedVertices =
1012       ((ctx->Light.Flags & (LIGHT_POSITIONAL|LIGHT_SPOT)) ||
1013        (ctx->Light.Model.ColorControl == GL_SEPARATE_SPECULAR_COLOR) ||
1014        (ctx->Light.Model.LocalViewer && (ctx->Light.Flags & LIGHT_SPECULAR)));
1015
1016
1017    /* Precompute some shading values.
1018     */
1019    if (ctx->Visual->RGBAflag)
1020    {
1021       GLuint sides = ((ctx->TriangleCaps & DD_TRI_LIGHT_TWOSIDE) ? 2 : 1);
1022       GLuint side;
1023       for (side=0; side < sides; side++) {
1024          struct gl_material *mat = &ctx->Light.Material[side];
1025
1026          COPY_3V(ctx->Light.BaseColor[side], mat->Emission);
1027          ACC_SCALE_3V(ctx->Light.BaseColor[side],
1028                       ctx->Light.Model.Ambient,
1029                       mat->Ambient);
1030
1031          FLOAT_COLOR_TO_UBYTE_COLOR(ctx->Light.BaseAlpha[side],
1032                                     ctx->Light.Material[side].Diffuse[3] );
1033       }
1034
1035       foreach (light, &ctx->Light.EnabledList) {
1036          for (side=0; side< sides; side++) {
1037             struct gl_material *mat = &ctx->Light.Material[side];
1038             SCALE_3V( light->MatDiffuse[side],  light->Diffuse, mat->Diffuse );
1039             SCALE_3V( light->MatAmbient[side],  light->Ambient, mat->Ambient );
1040             ACC_3V( ctx->Light.BaseColor[side], light->MatAmbient[side] );
1041             if (light->Flags & LIGHT_SPECULAR)
1042             {
1043                SCALE_3V( light->MatSpecular[side], light->Specular,
1044                          mat->Specular);
1045                light->IsMatSpecular[side] =
1046                   (LEN_SQUARED_3FV(light->MatSpecular[side]) > 1e-16);
1047             }
1048             else
1049                light->IsMatSpecular[side] = 0;
1050          }
1051       }
1052    }
1053    else
1054    {
1055       static GLfloat ci[3] = { .30, .59, .11 };
1056
1057       foreach(light, &ctx->Light.EnabledList) {
1058          light->dli = DOT3(ci, light->Diffuse);
1059          light->sli = DOT3(ci, light->Specular);
1060       }
1061    }
1062 }
1063
1064 /* Need to seriously restrict the circumstances under which these
1065  * calc's are performed.
1066  */
1067 void gl_compute_light_positions( GLcontext *ctx )
1068 {
1069    struct gl_light *light;
1070
1071    if (ctx->Light.NeedVertices && !ctx->Light.Model.LocalViewer) {
1072       GLfloat eye_z[3] = { 0, 0, 1 };
1073       if (!ctx->NeedEyeCoords) {
1074          TRANSFORM_NORMAL( ctx->EyeZDir, eye_z, ctx->ModelView.m );
1075       } else {
1076          COPY_3V( ctx->EyeZDir, eye_z );
1077       }
1078    }
1079
1080    foreach (light, &ctx->Light.EnabledList) {
1081
1082       if (!ctx->NeedEyeCoords) {
1083          TRANSFORM_POINT( light->Position, ctx->ModelView.inv,
1084                           light->EyePosition );
1085       } else {
1086          COPY_4FV( light->Position, light->EyePosition );
1087       }
1088
1089       if (!(light->Flags & LIGHT_POSITIONAL))
1090       {
1091          /* VP (VP) = Normalize( Position ) */
1092          COPY_3V( light->VP_inf_norm, light->Position );
1093          NORMALIZE_3FV( light->VP_inf_norm );
1094
1095          if (!ctx->Light.Model.LocalViewer)
1096          {
1097             /* h_inf_norm = Normalize( V_to_P + <0,0,1> ) */
1098             ADD_3V( light->h_inf_norm, light->VP_inf_norm, ctx->EyeZDir);
1099             NORMALIZE_3FV( light->h_inf_norm );
1100          }
1101
1102          light->VP_inf_spot_attenuation = 1.0;
1103       }
1104
1105       if (light->Flags & LIGHT_SPOT)
1106       {
1107          if (ctx->NeedEyeNormals) {
1108             COPY_3V( light->NormDirection, light->EyeDirection );
1109          } else {
1110             TRANSFORM_NORMAL( light->NormDirection,
1111                               light->EyeDirection,
1112                               ctx->ModelView.m);
1113          }
1114
1115          NORMALIZE_3FV( light->NormDirection );
1116
1117
1118          /* Unlikely occurrance?
1119           */
1120          if (!(light->Flags & LIGHT_POSITIONAL)) {
1121             GLfloat PV_dot_dir = - DOT3(light->VP_inf_norm,
1122                                         light->NormDirection);
1123
1124             if (PV_dot_dir > light->CosCutoff) {
1125                double x = PV_dot_dir * (EXP_TABLE_SIZE-1);
1126                int k = (int) x;
1127                light->VP_inf_spot_attenuation =
1128                   (light->SpotExpTable[k][0] +
1129                    (x-k)*light->SpotExpTable[k][1]);
1130             }
1131             else
1132                light->VP_inf_spot_attenuation = 0;
1133          }
1134       }
1135    }
1136 }
1137
1138
1139
1140
1141
1142 void gl_update_normal_transform( GLcontext *ctx )
1143 {
1144    GLuint new_flag = 0;
1145    normal_func *last = ctx->NormalTransform;
1146
1147    ctx->vb_rescale_factor = 1.0;
1148
1149    if (ctx->NeedEyeCoords) {
1150       if (ctx->NeedNormals) {
1151          GLuint transform = NORM_TRANSFORM_NO_ROT;
1152
1153          if (ctx->ModelView.flags & (MAT_FLAG_GENERAL |
1154                                      MAT_FLAG_ROTATION |
1155                                      MAT_FLAG_GENERAL_3D |
1156                                      MAT_FLAG_PERSPECTIVE))
1157             transform = NORM_TRANSFORM;
1158
1159
1160          new_flag = ctx->NewState & NEW_MODELVIEW;
1161          ctx->vb_rescale_factor = ctx->rescale_factor;
1162
1163          if (ctx->Transform.Normalize)
1164          {
1165             ctx->NormalTransform = gl_normal_tab[transform | NORM_NORMALIZE];
1166          }
1167          else if (ctx->Transform.RescaleNormals &&
1168                   ctx->rescale_factor != 1.0)
1169          {
1170             ctx->NormalTransform = gl_normal_tab[transform | NORM_RESCALE];
1171          }
1172          else
1173          {
1174             ctx->NormalTransform = gl_normal_tab[transform];
1175          }
1176       } else {
1177          ctx->NormalTransform = 0;
1178       }
1179    }
1180    else {
1181       if (ctx->NeedNormals) {
1182          ctx->vb_rescale_factor = 1.0/ctx->rescale_factor;
1183
1184          if (ctx->Transform.Normalize)
1185          {
1186             ctx->NormalTransform = gl_normal_tab[NORM_NORMALIZE];
1187          }
1188          else if (!ctx->Transform.RescaleNormals &&
1189                   ctx->rescale_factor != 1.0)
1190          {
1191             ctx->NormalTransform = gl_normal_tab[NORM_RESCALE];
1192          }
1193          else
1194          {
1195             ctx->NormalTransform = 0;
1196          }
1197       } else {
1198          ctx->NormalTransform = 0;
1199       }
1200    }
1201
1202    if (last != ctx->NormalTransform || new_flag)
1203       ctx->NewState |= NEW_NORMAL_TRANSFORM;
1204 }
1205