src/mesa/tnl/t_vb_lighttmp.h

   1 /*
   2  * Mesa 3-D graphics library
   3  * Version:  5.1
   4  *
   5  * Copyright (C) 1999-2003  Brian Paul   All Rights Reserved.
   6  *
   7  * Permission is hereby granted, free of charge, to any person obtaining a
   8  * copy of this software and associated documentation files (the "Software"),
   9  * to deal in the Software without restriction, including without limitation
  10  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  11  * and/or sell copies of the Software, and to permit persons to whom the
  12  * Software is furnished to do so, subject to the following conditions:
  13  *
  14  * The above copyright notice and this permission notice shall be included
  15  * in all copies or substantial portions of the Software.
  16  *
  17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  18  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  20  * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
  21  * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  22  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  23  *
  24  *
  25  * Authors:
  26  *    Brian Paul
  27  *    Keith Whitwell <keith@tungstengraphics.com>
  28  */
  29
  30
  31 #if (IDX & LIGHT_TWOSIDE)
  32 #  define NR_SIDES 2
  33 #else
  34 #  define NR_SIDES 1
  35 #endif
  36
  37
  38 /* define TRACE to trace lighting code */
  39 /* #define TRACE 1 */
  40
  41 /*
  42  * ctx is the current context
  43  * VB is the vertex buffer
  44  * stage is the lighting stage-private data
  45  * input is the vector of eye or object-space vertex coordinates
  46  */
  47 static void TAG(light_rgba_spec)( GLcontext *ctx,
  48                                   struct vertex_buffer *VB,
  49                                   struct tnl_pipeline_stage *stage,
  50                                   GLvector4f *input )
  51 {
  52    struct light_stage_data *store = LIGHT_STAGE_DATA(stage);
  53    GLfloat (*base)[3] = ctx->Light._BaseColor;
  54    GLfloat sumA[2];
  55    GLuint j;
  56
  57    const GLuint vstride = input->stride;
  58    const GLfloat *vertex = (GLfloat *)input->data;
  59    const GLuint nstride = VB->NormalPtr->stride;
  60    const GLfloat *normal = (GLfloat *)VB->NormalPtr->data;
  61
  62    GLfloat (*Fcolor)[4] = (GLfloat (*)[4]) store->LitColor[0].data;
  63    GLfloat (*Fspec)[4] = (GLfloat (*)[4]) store->LitSecondary[0].data;
  64 #if IDX & LIGHT_TWOSIDE
  65    GLfloat (*Bcolor)[4] = (GLfloat (*)[4]) store->LitColor[1].data;
  66    GLfloat (*Bspec)[4] = (GLfloat (*)[4]) store->LitSecondary[1].data;
  67 #endif
  68
  69    const GLuint nr = VB->Count;
  70
  71    (void) nstride;
  72    (void) vstride;
  73
  74 #ifdef TRACE
  75    fprintf(stderr, "%s\n", __FUNCTION__ );
  76 #endif
  77
  78    VB->ColorPtr[0] = &store->LitColor[0];
  79    VB->SecondaryColorPtr[0] = &store->LitSecondary[0];
  80    sumA[0] = ctx->Light.Material.Attrib[MAT_ATTRIB_FRONT_DIFFUSE][3];
  81
  82 #if IDX & LIGHT_TWOSIDE
  83    VB->ColorPtr[1] = &store->LitColor[1];
  84    VB->SecondaryColorPtr[1] = &store->LitSecondary[1];
  85    sumA[1] = ctx->Light.Material.Attrib[MAT_ATTRIB_BACK_DIFFUSE][3];
  86 #endif
  87
  88    /* Side-effects done, can we finish now?
  89     */
  90    if (stage->changed_inputs == 0)
  91       return;
  92
  93    for (j = 0; j < nr; j++,STRIDE_F(vertex,vstride),STRIDE_F(normal,nstride)) {
  94       GLfloat sum[2][3], spec[2][3];
  95       struct gl_light *light;
  96
  97 #if IDX & LIGHT_MATERIAL
  98       update_materials( ctx, store );
  99       sumA[0] = ctx->Light.Material.Attrib[MAT_ATTRIB_FRONT_DIFFUSE][3];
 100 #if IDX & LIGHT_TWOSIDE
 101       sumA[1] = ctx->Light.Material.Attrib[MAT_ATTRIB_BACK_DIFFUSE][3];
 102 #endif
 103 #endif
 104
 105       COPY_3V(sum[0], base[0]);
 106       ZERO_3V(spec[0]);
 107
 108 #if IDX & LIGHT_TWOSIDE
 109       COPY_3V(sum[1], base[1]);
 110       ZERO_3V(spec[1]);
 111 #endif
 112
 113       /* Add contribution from each enabled light source */
 114       foreach (light, &ctx->Light.EnabledList) {
 115          GLfloat n_dot_h;
 116          GLfloat correction;
 117          GLint side;
 118          GLfloat contrib[3];
 119          GLfloat attenuation;
 120          GLfloat VP[3];  /* unit vector from vertex to light */
 121          GLfloat n_dot_VP;       /* n dot VP */
 122          GLfloat *h;
 123
 124          /* compute VP and attenuation */
 125          if (!(light->_Flags & LIGHT_POSITIONAL)) {
 126             /* directional light */
 127             COPY_3V(VP, light->_VP_inf_norm);
 128             attenuation = light->_VP_inf_spot_attenuation;
 129          }
 130          else {
 131             GLfloat d;     /* distance from vertex to light */
 132
 133             SUB_3V(VP, light->_Position, vertex);
 134
 135             d = (GLfloat) LEN_3FV( VP );
 136
 137             if (d > 1e-6) {
 138                GLfloat invd = 1.0F / d;
 139                SELF_SCALE_SCALAR_3V(VP, invd);
 140             }
 141
 142             attenuation = 1.0F / (light->ConstantAttenuation + d *
 143                                   (light->LinearAttenuation + d *
 144                                    light->QuadraticAttenuation));
 145
 146             /* spotlight attenuation */
 147             if (light->_Flags & LIGHT_SPOT) {
 148                GLfloat PV_dot_dir = - DOT3(VP, light->_NormDirection);
 149
 150                if (PV_dot_dir<light->_CosCutoff) {
 151                   continue; /* this light makes no contribution */
 152                }
 153                else {
 154                   GLdouble x = PV_dot_dir * (EXP_TABLE_SIZE-1);
 155                   GLint k = (GLint) x;
 156                   GLfloat spot = (GLfloat) (light->_SpotExpTable[k][0]
 157                                     + (x-k)*light->_SpotExpTable[k][1]);
 158                   attenuation *= spot;
 159                }
 160             }
 161          }
 162
 163          if (attenuation < 1e-3)
 164             continue;           /* this light makes no contribution */
 165
 166          /* Compute dot product or normal and vector from V to light pos */
 167          n_dot_VP = DOT3( normal, VP );
 168
 169          /* Which side gets the diffuse & specular terms? */
 170          if (n_dot_VP < 0.0F) {
 171             ACC_SCALE_SCALAR_3V(sum[0], attenuation, light->_MatAmbient[0]);
 172 #if IDX & LIGHT_TWOSIDE
 173             side = 1;
 174             correction = -1;
 175             n_dot_VP = -n_dot_VP;
 176 #else
 177             continue;
 178 #endif
 179          }
 180          else {
 181 #if IDX & LIGHT_TWOSIDE
 182             ACC_SCALE_SCALAR_3V( sum[1], attenuation, light->_MatAmbient[1]);
 183 #endif
 184             side = 0;
 185             correction = 1;
 186          }
 187
 188          /* diffuse term */
 189          COPY_3V(contrib, light->_MatAmbient[side]);
 190          ACC_SCALE_SCALAR_3V(contrib, n_dot_VP, light->_MatDiffuse[side]);
 191          ACC_SCALE_SCALAR_3V(sum[side], attenuation, contrib );
 192
 193          /* specular term - cannibalize VP... */
 194          if (ctx->Light.Model.LocalViewer) {
 195             GLfloat v[3];
 196             COPY_3V(v, vertex);
 197             NORMALIZE_3FV(v);
 198             SUB_3V(VP, VP, v);                /* h = VP + VPe */
 199             h = VP;
 200             NORMALIZE_3FV(h);
 201          }
 202          else if (light->_Flags & LIGHT_POSITIONAL) {
 203             h = VP;
 204             ACC_3V(h, ctx->_EyeZDir);
 205             NORMALIZE_3FV(h);
 206          }
 207          else {
 208             h = light->_h_inf_norm;
 209          }
 210
 211          n_dot_h = correction * DOT3(normal, h);
 212
 213          if (n_dot_h > 0.0F) {
 214             GLfloat spec_coef;
 215             struct gl_shine_tab *tab = ctx->_ShineTable[side];
 216             GET_SHINE_TAB_ENTRY( tab, n_dot_h, spec_coef );
 217
 218             if (spec_coef > 1.0e-10) {
 219                spec_coef *= attenuation;
 220                ACC_SCALE_SCALAR_3V( spec[side], spec_coef,
 221                                     light->_MatSpecular[side]);
 222             }
 223          }
 224       } /*loop over lights*/
 225
 226       COPY_3V( Fcolor[j], sum[0] );
 227       COPY_3V( Fspec[j], spec[0] );
 228       Fcolor[j][3] = sumA[0];
 229
 230 #if IDX & LIGHT_TWOSIDE
 231       COPY_3V( Bcolor[j], sum[1] );
 232       COPY_3V( Bspec[j], spec[1] );
 233       Bcolor[j][3] = sumA[1];
 234 #endif
 235    }
 236 }
 237
 238
 239 static void TAG(light_rgba)( GLcontext *ctx,
 240                              struct vertex_buffer *VB,
 241                              struct tnl_pipeline_stage *stage,
 242                              GLvector4f *input )
 243 {
 244    struct light_stage_data *store = LIGHT_STAGE_DATA(stage);
 245    GLuint j;
 246
 247    GLfloat (*base)[3] = ctx->Light._BaseColor;
 248    GLfloat sumA[2];
 249
 250    const GLuint vstride = input->stride;
 251    const GLfloat *vertex = (GLfloat *) input->data;
 252    const GLuint nstride = VB->NormalPtr->stride;
 253    const GLfloat *normal = (GLfloat *)VB->NormalPtr->data;
 254
 255    GLfloat (*Fcolor)[4] = (GLfloat (*)[4]) store->LitColor[0].data;
 256    GLfloat (*Bcolor)[4] = (GLfloat (*)[4]) store->LitColor[1].data;
 257    GLfloat (*color[2])[4];
 258
 259    const GLuint nr = VB->Count;
 260
 261 #ifdef TRACE
 262    fprintf(stderr, "%s\n", __FUNCTION__ );
 263 #endif
 264
 265    (void) nstride;
 266    (void) vstride;
 267
 268    color[0] = Fcolor;
 269    color[1] = Bcolor;
 270
 271    VB->ColorPtr[0] = &store->LitColor[0];
 272    sumA[0] = ctx->Light.Material.Attrib[MAT_ATTRIB_FRONT_DIFFUSE][3];
 273
 274 #if IDX & LIGHT_TWOSIDE
 275    VB->ColorPtr[1] = &store->LitColor[1];
 276    sumA[1] = ctx->Light.Material.Attrib[MAT_ATTRIB_BACK_DIFFUSE][3];
 277 #endif
 278
 279    if (stage->changed_inputs == 0)
 280       return;
 281
 282    for (j = 0; j < nr; j++,STRIDE_F(vertex,vstride),STRIDE_F(normal,nstride)) {
 283       GLfloat sum[2][3];
 284       struct gl_light *light;
 285
 286       if ( IDX & LIGHT_MATERIAL ) {
 287          update_materials( ctx, store );
 288          sumA[0] = ctx->Light.Material.Attrib[MAT_ATTRIB_FRONT_DIFFUSE][3];
 289 #if IDX & LIGHT_TWOSIDE
 290          sumA[1] = ctx->Light.Material.Attrib[MAT_ATTRIB_BACK_DIFFUSE][3];
 291 #endif
 292       }
 293
 294       COPY_3V(sum[0], base[0]);
 295
 296       if ( IDX & LIGHT_TWOSIDE )
 297          COPY_3V(sum[1], base[1]);
 298
 299       /* Add contribution from each enabled light source */
 300       foreach (light, &ctx->Light.EnabledList) {
 301
 302          GLfloat n_dot_h;
 303          GLfloat correction;
 304          GLint side;
 305          GLfloat contrib[3];
 306          GLfloat attenuation = 1.0;
 307          GLfloat VP[3];          /* unit vector from vertex to light */
 308          GLfloat n_dot_VP;       /* n dot VP */
 309          GLfloat *h;
 310
 311          /* compute VP and attenuation */
 312          if (!(light->_Flags & LIGHT_POSITIONAL)) {
 313             /* directional light */
 314             COPY_3V(VP, light->_VP_inf_norm);
 315             attenuation = light->_VP_inf_spot_attenuation;
 316          }
 317          else {
 318             GLfloat d;     /* distance from vertex to light */
 319
 320
 321             SUB_3V(VP, light->_Position, vertex);
 322
 323             d = (GLfloat) LEN_3FV( VP );
 324
 325             if ( d > 1e-6) {
 326                GLfloat invd = 1.0F / d;
 327                SELF_SCALE_SCALAR_3V(VP, invd);
 328             }
 329
 330             attenuation = 1.0F / (light->ConstantAttenuation + d *
 331                                   (light->LinearAttenuation + d *
 332                                    light->QuadraticAttenuation));
 333
 334             /* spotlight attenuation */
 335             if (light->_Flags & LIGHT_SPOT) {
 336                GLfloat PV_dot_dir = - DOT3(VP, light->_NormDirection);
 337
 338                if (PV_dot_dir<light->_CosCutoff) {
 339                   continue; /* this light makes no contribution */
 340                }
 341                else {
 342                   GLdouble x = PV_dot_dir * (EXP_TABLE_SIZE-1);
 343                   GLint k = (GLint) x;
 344                   GLfloat spot = (GLfloat) (light->_SpotExpTable[k][0]
 345                                   + (x-k)*light->_SpotExpTable[k][1]);
 346                   attenuation *= spot;
 347                }
 348             }
 349          }
 350
 351          if (attenuation < 1e-3)
 352             continue;           /* this light makes no contribution */
 353
 354          /* Compute dot product or normal and vector from V to light pos */
 355          n_dot_VP = DOT3( normal, VP );
 356
 357          /* which side are we lighting? */
 358          if (n_dot_VP < 0.0F) {
 359             ACC_SCALE_SCALAR_3V(sum[0], attenuation, light->_MatAmbient[0]);
 360 #if IDX & LIGHT_TWOSIDE
 361             side = 1;
 362             correction = -1;
 363             n_dot_VP = -n_dot_VP;
 364 #else
 365             continue;
 366 #endif
 367          }
 368          else {
 369 #if IDX & LIGHT_TWOSIDE
 370             ACC_SCALE_SCALAR_3V( sum[1], attenuation, light->_MatAmbient[1]);
 371 #endif
 372             side = 0;
 373             correction = 1;
 374          }
 375
 376          COPY_3V(contrib, light->_MatAmbient[side]);
 377
 378          /* diffuse term */
 379          ACC_SCALE_SCALAR_3V(contrib, n_dot_VP, light->_MatDiffuse[side]);
 380
 381          /* specular term - cannibalize VP... */
 382          {
 383             if (ctx->Light.Model.LocalViewer) {
 384                GLfloat v[3];
 385                COPY_3V(v, vertex);
 386                NORMALIZE_3FV(v);
 387                SUB_3V(VP, VP, v);                /* h = VP + VPe */
 388                h = VP;
 389                NORMALIZE_3FV(h);
 390             }
 391             else if (light->_Flags & LIGHT_POSITIONAL) {
 392                h = VP;
 393                ACC_3V(h, ctx->_EyeZDir);
 394                NORMALIZE_3FV(h);
 395             }
 396             else {
 397                h = light->_h_inf_norm;
 398             }
 399
 400             n_dot_h = correction * DOT3(normal, h);
 401
 402             if (n_dot_h > 0.0F)
 403             {
 404                GLfloat spec_coef;
 405                struct gl_shine_tab *tab = ctx->_ShineTable[side];
 406
 407                GET_SHINE_TAB_ENTRY( tab, n_dot_h, spec_coef );
 408
 409                ACC_SCALE_SCALAR_3V( contrib, spec_coef,
 410                                     light->_MatSpecular[side]);
 411             }
 412          }
 413
 414          ACC_SCALE_SCALAR_3V( sum[side], attenuation, contrib );
 415       }
 416
 417       COPY_3V( Fcolor[j], sum[0] );
 418       Fcolor[j][3] = sumA[0];
 419
 420 #if IDX & LIGHT_TWOSIDE
 421       COPY_3V( Bcolor[j], sum[1] );
 422       Bcolor[j][3] = sumA[1];
 423 #endif
 424    }
 425 }
 426
 427
 428
 429
 430 /* As below, but with just a single light.
 431  */
 432 static void TAG(light_fast_rgba_single)( GLcontext *ctx,
 433                                          struct vertex_buffer *VB,
 434                                          struct tnl_pipeline_stage *stage,
 435                                          GLvector4f *input )
 436
 437 {
 438    struct light_stage_data *store = LIGHT_STAGE_DATA(stage);
 439    const GLuint nstride = VB->NormalPtr->stride;
 440    const GLfloat *normal = (GLfloat *)VB->NormalPtr->data;
 441    GLfloat (*Fcolor)[4] = (GLfloat (*)[4]) store->LitColor[0].data;
 442 #if IDX & LIGHT_TWOSIDE
 443    GLfloat (*Bcolor)[4] = (GLfloat (*)[4]) store->LitColor[1].data;
 444 #endif
 445    const struct gl_light *light = ctx->Light.EnabledList.next;
 446    GLuint j = 0;
 447    GLfloat base[2][4];
 448    const GLuint nr = VB->Count;
 449
 450 #ifdef TRACE
 451    fprintf(stderr, "%s\n", __FUNCTION__ );
 452 #endif
 453
 454    (void) input;                /* doesn't refer to Eye or Obj */
 455    (void) nr;
 456    (void) nstride;
 457
 458    VB->ColorPtr[0] = &store->LitColor[0];
 459 #if IDX & LIGHT_TWOSIDE
 460    VB->ColorPtr[1] = &store->LitColor[1];
 461 #endif
 462
 463    if (stage->changed_inputs == 0)
 464       return;
 465
 466    for (j = 0; j < nr; j++, STRIDE_F(normal,nstride)) {
 467
 468       GLfloat n_dot_VP;
 469
 470       if ( IDX & LIGHT_MATERIAL )
 471          update_materials( ctx, store );
 472
 473       /* No attenuation, so incoporate _MatAmbient into base color.
 474        */
 475       if ( j == 0 || (IDX & LIGHT_MATERIAL) ) {
 476          COPY_3V(base[0], light->_MatAmbient[0]);
 477          ACC_3V(base[0], ctx->Light._BaseColor[0] );
 478          base[0][3] = ctx->Light.Material.Attrib[MAT_ATTRIB_FRONT_DIFFUSE][3];
 479
 480 #if IDX & LIGHT_TWOSIDE
 481          COPY_3V(base[1], light->_MatAmbient[1]);
 482          ACC_3V(base[1], ctx->Light._BaseColor[1]);
 483          base[1][3] = ctx->Light.Material.Attrib[MAT_ATTRIB_BACK_DIFFUSE][3];
 484 #endif
 485       }
 486
 487       n_dot_VP = DOT3(normal, light->_VP_inf_norm);
 488
 489       if (n_dot_VP < 0.0F) {
 490 #if IDX & LIGHT_TWOSIDE
 491          GLfloat n_dot_h = -DOT3(normal, light->_h_inf_norm);
 492          GLfloat sum[3];
 493          COPY_3V(sum, base[1]);
 494          ACC_SCALE_SCALAR_3V(sum, -n_dot_VP, light->_MatDiffuse[1]);
 495          if (n_dot_h > 0.0F) {
 496             GLfloat spec;
 497             GET_SHINE_TAB_ENTRY( ctx->_ShineTable[1], n_dot_h, spec );
 498             ACC_SCALE_SCALAR_3V(sum, spec, light->_MatSpecular[1]);
 499          }
 500          COPY_3V(Bcolor[j], sum );
 501          Bcolor[j][3] = base[1][3];
 502 #endif
 503          COPY_4FV(Fcolor[j], base[0]);
 504       }
 505       else {
 506          GLfloat n_dot_h = DOT3(normal, light->_h_inf_norm);
 507          GLfloat sum[3];
 508          COPY_3V(sum, base[0]);
 509          ACC_SCALE_SCALAR_3V(sum, n_dot_VP, light->_MatDiffuse[0]);
 510          if (n_dot_h > 0.0F) {
 511             GLfloat spec;
 512             GET_SHINE_TAB_ENTRY( ctx->_ShineTable[0], n_dot_h, spec );
 513             ACC_SCALE_SCALAR_3V(sum, spec, light->_MatSpecular[0]);
 514
 515          }
 516          COPY_3V(Fcolor[j], sum );
 517          Fcolor[j][3] = base[0][3];
 518 #if IDX & LIGHT_TWOSIDE
 519          COPY_4FV(Bcolor[j], base[1]);
 520 #endif
 521       }
 522    }
 523 }
 524
 525
 526 /* Light infinite lights
 527  */
 528 static void TAG(light_fast_rgba)( GLcontext *ctx,
 529                                   struct vertex_buffer *VB,
 530                                   struct tnl_pipeline_stage *stage,
 531                                   GLvector4f *input )
 532 {
 533    struct light_stage_data *store = LIGHT_STAGE_DATA(stage);
 534    GLfloat sumA[2];
 535    const GLuint nstride = VB->NormalPtr->stride;
 536    const GLfloat *normal = (GLfloat *)VB->NormalPtr->data;
 537    GLfloat (*Fcolor)[4] = (GLfloat (*)[4]) store->LitColor[0].data;
 538 #if IDX & LIGHT_TWOSIDE
 539    GLfloat (*Bcolor)[4] = (GLfloat (*)[4]) store->LitColor[1].data;
 540 #endif
 541    GLuint j = 0;
 542    const GLuint nr = VB->Count;
 543    const struct gl_light *light;
 544
 545 #ifdef TRACE
 546    fprintf(stderr, "%s %d\n", __FUNCTION__, nr );
 547 #endif
 548
 549    (void) input;
 550    (void) nr;
 551    (void) nstride;
 552
 553    sumA[0] = ctx->Light.Material.Attrib[MAT_ATTRIB_FRONT_DIFFUSE][3];
 554    sumA[1] = ctx->Light.Material.Attrib[MAT_ATTRIB_BACK_DIFFUSE][3];
 555
 556    VB->ColorPtr[0] = &store->LitColor[0];
 557 #if IDX & LIGHT_TWOSIDE
 558    VB->ColorPtr[1] = &store->LitColor[1];
 559 #endif
 560
 561    if (stage->changed_inputs == 0)
 562       return;
 563
 564    for (j = 0; j < nr; j++, STRIDE_F(normal,nstride)) {
 565
 566       GLfloat sum[2][3];
 567
 568       if ( IDX & LIGHT_MATERIAL ) {
 569          update_materials( ctx, store );
 570
 571          sumA[0] = ctx->Light.Material.Attrib[MAT_ATTRIB_FRONT_DIFFUSE][3];
 572 #if IDX & LIGHT_TWOSIDE
 573          sumA[1] = ctx->Light.Material.Attrib[MAT_ATTRIB_BACK_DIFFUSE][3];
 574 #endif
 575       }
 576
 577
 578       COPY_3V(sum[0], ctx->Light._BaseColor[0]);
 579 #if IDX & LIGHT_TWOSIDE
 580       COPY_3V(sum[1], ctx->Light._BaseColor[1]);
 581 #endif
 582
 583       foreach (light, &ctx->Light.EnabledList) {
 584          GLfloat n_dot_h, n_dot_VP, spec;
 585
 586          ACC_3V(sum[0], light->_MatAmbient[0]);
 587 #if IDX & LIGHT_TWOSIDE
 588          ACC_3V(sum[1], light->_MatAmbient[1]);
 589 #endif
 590
 591          n_dot_VP = DOT3(normal, light->_VP_inf_norm);
 592
 593          if (n_dot_VP > 0.0F) {
 594             ACC_SCALE_SCALAR_3V(sum[0], n_dot_VP, light->_MatDiffuse[0]);
 595             n_dot_h = DOT3(normal, light->_h_inf_norm);
 596             if (n_dot_h > 0.0F) {
 597                struct gl_shine_tab *tab = ctx->_ShineTable[0];
 598                GET_SHINE_TAB_ENTRY( tab, n_dot_h, spec );
 599                ACC_SCALE_SCALAR_3V( sum[0], spec, light->_MatSpecular[0]);
 600             }
 601          }
 602 #if IDX & LIGHT_TWOSIDE
 603          else {
 604             ACC_SCALE_SCALAR_3V(sum[1], -n_dot_VP, light->_MatDiffuse[1]);
 605             n_dot_h = -DOT3(normal, light->_h_inf_norm);
 606             if (n_dot_h > 0.0F) {
 607                struct gl_shine_tab *tab = ctx->_ShineTable[1];
 608                GET_SHINE_TAB_ENTRY( tab, n_dot_h, spec );
 609                ACC_SCALE_SCALAR_3V( sum[1], spec, light->_MatSpecular[1]);
 610             }
 611          }
 612 #endif
 613       }
 614
 615       COPY_3V( Fcolor[j], sum[0] );
 616       Fcolor[j][3] = sumA[0];
 617
 618 #if IDX & LIGHT_TWOSIDE
 619       COPY_3V( Bcolor[j], sum[1] );
 620       Bcolor[j][3] = sumA[1];
 621 #endif
 622    }
 623 }
 624
 625
 626
 627
 628
 629 /*
 630  * Use current lighting/material settings to compute the color indexes
 631  * for an array of vertices.
 632  * Input:  n - number of vertices to light
 633  *         side - 0=use front material, 1=use back material
 634  *         vertex - array of [n] vertex position in eye coordinates
 635  *         normal - array of [n] surface normal vector
 636  * Output:  indexResult - resulting array of [n] color indexes
 637  */
 638 static void TAG(light_ci)( GLcontext *ctx,
 639                            struct vertex_buffer *VB,
 640                            struct tnl_pipeline_stage *stage,
 641                            GLvector4f *input )
 642 {
 643    struct light_stage_data *store = LIGHT_STAGE_DATA(stage);
 644    GLuint j;
 645    const GLuint vstride = input->stride;
 646    const GLfloat *vertex = (GLfloat *) input->data;
 647    const GLuint nstride = VB->NormalPtr->stride;
 648    const GLfloat *normal = (GLfloat *)VB->NormalPtr->data;
 649    GLfloat *indexResult[2];
 650    const GLuint nr = VB->Count;
 651
 652 #ifdef TRACE
 653    fprintf(stderr, "%s\n", __FUNCTION__ );
 654 #endif
 655
 656    (void) nstride;
 657    (void) vstride;
 658
 659    VB->IndexPtr[0] = &store->LitIndex[0];
 660 #if IDX & LIGHT_TWOSIDE
 661    VB->IndexPtr[1] = &store->LitIndex[1];
 662 #endif
 663
 664    if (stage->changed_inputs == 0)
 665       return;
 666
 667    indexResult[0] = (GLfloat *)VB->IndexPtr[0]->data;
 668 #if IDX & LIGHT_TWOSIDE
 669    indexResult[1] = (GLfloat *)VB->IndexPtr[1]->data;
 670 #endif
 671
 672    /* loop over vertices */
 673    for (j=0; j<nr; j++,STRIDE_F(vertex,vstride),STRIDE_F(normal, nstride)) {
 674       GLfloat diffuse[2], specular[2];
 675       GLuint side = 0;
 676       struct gl_light *light;
 677
 678       if ( IDX & LIGHT_MATERIAL )
 679          update_materials( ctx, store );
 680
 681       diffuse[0] = specular[0] = 0.0F;
 682
 683       if ( IDX & LIGHT_TWOSIDE ) {
 684          diffuse[1] = specular[1] = 0.0F;
 685       }
 686
 687       /* Accumulate diffuse and specular from each light source */
 688       foreach (light, &ctx->Light.EnabledList) {
 689
 690          GLfloat attenuation = 1.0F;
 691          GLfloat VP[3];  /* unit vector from vertex to light */
 692          GLfloat n_dot_VP;  /* dot product of l and n */
 693          GLfloat *h, n_dot_h, correction = 1.0;
 694
 695          /* compute l and attenuation */
 696          if (!(light->_Flags & LIGHT_POSITIONAL)) {
 697             /* directional light */
 698             COPY_3V(VP, light->_VP_inf_norm);
 699          }
 700          else {
 701             GLfloat d;     /* distance from vertex to light */
 702
 703             SUB_3V(VP, light->_Position, vertex);
 704
 705             d = (GLfloat) LEN_3FV( VP );
 706             if ( d > 1e-6) {
 707                GLfloat invd = 1.0F / d;
 708                SELF_SCALE_SCALAR_3V(VP, invd);
 709             }
 710
 711             attenuation = 1.0F / (light->ConstantAttenuation + d *
 712                                   (light->LinearAttenuation + d *
 713                                    light->QuadraticAttenuation));
 714
 715             /* spotlight attenuation */
 716             if (light->_Flags & LIGHT_SPOT) {
 717                GLfloat PV_dot_dir = - DOT3(VP, light->_NormDirection);
 718                if (PV_dot_dir < light->_CosCutoff) {
 719                   continue; /* this light makes no contribution */
 720                }
 721                else {
 722                   GLdouble x = PV_dot_dir * (EXP_TABLE_SIZE-1);
 723                   GLint k = (GLint) x;
 724                   GLfloat spot = (GLfloat) (light->_SpotExpTable[k][0]
 725                                   + (x-k)*light->_SpotExpTable[k][1]);
 726                   attenuation *= spot;
 727                }
 728             }
 729          }
 730
 731          if (attenuation < 1e-3)
 732             continue;           /* this light makes no contribution */
 733
 734          n_dot_VP = DOT3( normal, VP );
 735
 736          /* which side are we lighting? */
 737          if (n_dot_VP < 0.0F) {
 738 #if IDX & LIGHT_TWOSIDE
 739             side = 1;
 740             correction = -1;
 741             n_dot_VP = -n_dot_VP;
 742 #else
 743             continue;
 744 #endif
 745          }
 746
 747          /* accumulate diffuse term */
 748          diffuse[side] += n_dot_VP * light->_dli * attenuation;
 749
 750          /* specular term */
 751          if (ctx->Light.Model.LocalViewer) {
 752             GLfloat v[3];
 753             COPY_3V(v, vertex);
 754             NORMALIZE_3FV(v);
 755             SUB_3V(VP, VP, v);                /* h = VP + VPe */
 756             h = VP;
 757             NORMALIZE_3FV(h);
 758          }
 759          else if (light->_Flags & LIGHT_POSITIONAL) {
 760             h = VP;
 761             /* Strangely, disabling this addition fixes a conformance
 762              * problem.  If this code is enabled, l_sed.c fails.
 763              */
 764             /*ACC_3V(h, ctx->_EyeZDir);*/
 765             NORMALIZE_3FV(h);
 766          }
 767          else {
 768             h = light->_h_inf_norm;
 769          }
 770
 771          n_dot_h = correction * DOT3(normal, h);
 772          if (n_dot_h > 0.0F) {
 773             GLfloat spec_coef;
 774             struct gl_shine_tab *tab = ctx->_ShineTable[side];
 775             GET_SHINE_TAB_ENTRY( tab, n_dot_h, spec_coef);
 776             specular[side] += spec_coef * light->_sli * attenuation;
 777          }
 778       } /*loop over lights*/
 779
 780       /* Now compute final color index */
 781       for (side = 0 ; side < NR_SIDES ; side++) {
 782          const GLfloat *ind = ctx->Light.Material.Attrib[MAT_ATTRIB_FRONT_INDEXES + side];
 783          GLfloat index;
 784
 785          if (specular[side] > 1.0F) {
 786             index = ind[MAT_INDEX_SPECULAR];
 787          }
 788          else {
 789             GLfloat d_a = ind[MAT_INDEX_DIFFUSE] - ind[MAT_INDEX_AMBIENT];
 790             GLfloat s_a = ind[MAT_INDEX_SPECULAR] - ind[MAT_INDEX_AMBIENT];
 791             index = (ind[MAT_INDEX_AMBIENT]
 792                      + diffuse[side] * (1.0F-specular[side]) * d_a
 793                      + specular[side] * s_a);
 794             if (index > ind[MAT_INDEX_SPECULAR]) {
 795                index = ind[MAT_INDEX_SPECULAR];
 796             }
 797          }
 798          indexResult[side][j] = index;
 799       }
 800    } /*for vertex*/
 801 }
 802
 803
 804
 805 static void TAG(init_light_tab)( void )
 806 {
 807    _tnl_light_tab[IDX] = TAG(light_rgba);
 808    _tnl_light_fast_tab[IDX] = TAG(light_fast_rgba);
 809    _tnl_light_fast_single_tab[IDX] = TAG(light_fast_rgba_single);
 810    _tnl_light_spec_tab[IDX] = TAG(light_rgba_spec);
 811    _tnl_light_ci_tab[IDX] = TAG(light_ci);
 812 }
 813
 814
 815 #undef TAG
 816 #undef IDX
 817 #undef NR_SIDES