src/mesa/tnl/t_vb_lighttmp.h

   1
   2 /*
   3  * Mesa 3-D graphics library
   4  * Version:  4.1
   5  *
   6  * Copyright (C) 1999-2001  Brian Paul   All Rights Reserved.
   7  *
   8  * Permission is hereby granted, free of charge, to any person obtaining a
   9  * copy of this software and associated documentation files (the "Software"),
  10  * to deal in the Software without restriction, including without limitation
  11  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  12  * and/or sell copies of the Software, and to permit persons to whom the
  13  * Software is furnished to do so, subject to the following conditions:
  14  *
  15  * The above copyright notice and this permission notice shall be included
  16  * in all copies or substantial portions of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  19  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  20  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  21  * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
  22  * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  23  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  24  *
  25  *
  26  * Authors:
  27  *    Brian Paul
  28  *    Keith Whitwell <keith@tungstengraphics.com>
  29  */
  30
  31
  32 #if (IDX & LIGHT_TWOSIDE)
  33 #  define NR_SIDES 2
  34 #else
  35 #  define NR_SIDES 1
  36 #endif
  37
  38
  39 /* define TRACE to trace lighting code */
  40 /* #define TRACE 1 */
  41
  42 /*
  43  * ctx is the current context
  44  * VB is the vertex buffer
  45  * stage is the lighting stage-private data
  46  * input is the vector of eye or object-space vertex coordinates
  47  */
  48 static void TAG(light_rgba_spec)( GLcontext *ctx,
  49                                   struct vertex_buffer *VB,
  50                                   struct tnl_pipeline_stage *stage,
  51                                   GLvector4f *input )
  52 {
  53    struct light_stage_data *store = LIGHT_STAGE_DATA(stage);
  54    GLfloat (*base)[3] = ctx->Light._BaseColor;
  55    GLfloat sumA[2];
  56    GLuint j;
  57
  58    const GLuint vstride = input->stride;
  59    const GLfloat *vertex = (GLfloat *)input->data;
  60    const GLuint nstride = VB->NormalPtr->stride;
  61    const GLfloat *normal = (GLfloat *)VB->NormalPtr->data;
  62
  63    GLfloat (*Fcolor)[4] = (GLfloat (*)[4]) store->LitColor[0].data;
  64    GLfloat (*Bcolor)[4] = (GLfloat (*)[4]) store->LitColor[1].data;
  65    GLfloat (*Fspec)[4] = (GLfloat (*)[4]) store->LitSecondary[0].data;
  66    GLfloat (*Bspec)[4] = (GLfloat (*)[4]) store->LitSecondary[1].data;
  67
  68    const GLuint nr = VB->Count;
  69
  70    (void) nstride;
  71    (void) vstride;
  72
  73 #ifdef TRACE
  74    fprintf(stderr, "%s\n", __FUNCTION__ );
  75 #endif
  76
  77    VB->ColorPtr[0] = &store->LitColor[0];
  78    VB->SecondaryColorPtr[0] = &store->LitSecondary[0];
  79    sumA[0] = ctx->Light.Material.Attrib[MAT_ATTRIB_FRONT_DIFFUSE][3];
  80
  81    if (IDX & LIGHT_TWOSIDE) {
  82       VB->ColorPtr[1] = &store->LitColor[1];
  83       VB->SecondaryColorPtr[1] = &store->LitSecondary[1];
  84       sumA[1] = ctx->Light.Material.Attrib[MAT_ATTRIB_BACK_DIFFUSE][3];
  85    }
  86
  87    /* Side-effects done, can we finish now?
  88     */
  89    if (stage->changed_inputs == 0)
  90       return;
  91
  92    for (j = 0; j < nr; j++,STRIDE_F(vertex,vstride),STRIDE_F(normal,nstride)) {
  93       GLfloat sum[2][3], spec[2][3];
  94       struct gl_light *light;
  95
  96       if ( IDX & LIGHT_MATERIAL ) {
  97          update_materials( ctx, store );
  98          sumA[0] = ctx->Light.Material.Attrib[MAT_ATTRIB_FRONT_DIFFUSE][3];
  99          if (IDX & LIGHT_TWOSIDE)
 100             sumA[1] = ctx->Light.Material.Attrib[MAT_ATTRIB_BACK_DIFFUSE][3];
 101       }
 102
 103       COPY_3V(sum[0], base[0]);
 104       ZERO_3V(spec[0]);
 105
 106       if (IDX & LIGHT_TWOSIDE) {
 107          COPY_3V(sum[1], base[1]);
 108          ZERO_3V(spec[1]);
 109       }
 110
 111       /* Add contribution from each enabled light source */
 112       foreach (light, &ctx->Light.EnabledList) {
 113          GLfloat n_dot_h;
 114          GLfloat correction;
 115          GLint side;
 116          GLfloat contrib[3];
 117          GLfloat attenuation;
 118          GLfloat VP[3];  /* unit vector from vertex to light */
 119          GLfloat n_dot_VP;       /* n dot VP */
 120          GLfloat *h;
 121
 122          /* compute VP and attenuation */
 123          if (!(light->_Flags & LIGHT_POSITIONAL)) {
 124             /* directional light */
 125             COPY_3V(VP, light->_VP_inf_norm);
 126             attenuation = light->_VP_inf_spot_attenuation;
 127          }
 128          else {
 129             GLfloat d;     /* distance from vertex to light */
 130
 131             SUB_3V(VP, light->_Position, vertex);
 132
 133             d = (GLfloat) LEN_3FV( VP );
 134
 135             if (d > 1e-6) {
 136                GLfloat invd = 1.0F / d;
 137                SELF_SCALE_SCALAR_3V(VP, invd);
 138             }
 139
 140             attenuation = 1.0F / (light->ConstantAttenuation + d *
 141                                   (light->LinearAttenuation + d *
 142                                    light->QuadraticAttenuation));
 143
 144             /* spotlight attenuation */
 145             if (light->_Flags & LIGHT_SPOT) {
 146                GLfloat PV_dot_dir = - DOT3(VP, light->_NormDirection);
 147
 148                if (PV_dot_dir<light->_CosCutoff) {
 149                   continue; /* this light makes no contribution */
 150                }
 151                else {
 152                   GLdouble x = PV_dot_dir * (EXP_TABLE_SIZE-1);
 153                   GLint k = (GLint) x;
 154                   GLfloat spot = (GLfloat) (light->_SpotExpTable[k][0]
 155                                     + (x-k)*light->_SpotExpTable[k][1]);
 156                   attenuation *= spot;
 157                }
 158             }
 159          }
 160
 161          if (attenuation < 1e-3)
 162             continue;           /* this light makes no contribution */
 163
 164          /* Compute dot product or normal and vector from V to light pos */
 165          n_dot_VP = DOT3( normal, VP );
 166
 167          /* Which side gets the diffuse & specular terms? */
 168          if (n_dot_VP < 0.0F) {
 169             ACC_SCALE_SCALAR_3V(sum[0], attenuation, light->_MatAmbient[0]);
 170             if (!(IDX & LIGHT_TWOSIDE)) {
 171                continue;
 172             }
 173             side = 1;
 174             correction = -1;
 175             n_dot_VP = -n_dot_VP;
 176          }
 177          else {
 178             if (IDX & LIGHT_TWOSIDE) {
 179                ACC_SCALE_SCALAR_3V( sum[1], attenuation, light->_MatAmbient[1]);
 180             }
 181             side = 0;
 182             correction = 1;
 183          }
 184
 185          /* diffuse term */
 186          COPY_3V(contrib, light->_MatAmbient[side]);
 187          ACC_SCALE_SCALAR_3V(contrib, n_dot_VP, light->_MatDiffuse[side]);
 188          ACC_SCALE_SCALAR_3V(sum[side], attenuation, contrib );
 189
 190          /* specular term - cannibalize VP... */
 191          if (ctx->Light.Model.LocalViewer) {
 192             GLfloat v[3];
 193             COPY_3V(v, vertex);
 194             NORMALIZE_3FV(v);
 195             SUB_3V(VP, VP, v);                /* h = VP + VPe */
 196             h = VP;
 197             NORMALIZE_3FV(h);
 198          }
 199          else if (light->_Flags & LIGHT_POSITIONAL) {
 200             h = VP;
 201             ACC_3V(h, ctx->_EyeZDir);
 202             NORMALIZE_3FV(h);
 203          }
 204          else {
 205             h = light->_h_inf_norm;
 206          }
 207
 208          n_dot_h = correction * DOT3(normal, h);
 209
 210          if (n_dot_h > 0.0F) {
 211             GLfloat spec_coef;
 212             struct gl_shine_tab *tab = ctx->_ShineTable[side];
 213             GET_SHINE_TAB_ENTRY( tab, n_dot_h, spec_coef );
 214
 215             if (spec_coef > 1.0e-10) {
 216                spec_coef *= attenuation;
 217                ACC_SCALE_SCALAR_3V( spec[side], spec_coef,
 218                                     light->_MatSpecular[side]);
 219             }
 220          }
 221       } /*loop over lights*/
 222
 223       COPY_3V( Fcolor[j], sum[0] );
 224       COPY_3V( Fspec[j], spec[0] );
 225       Fcolor[j][3] = sumA[0];
 226
 227       if (IDX & LIGHT_TWOSIDE) {
 228          COPY_3V( Bcolor[j], sum[1] );
 229          COPY_3V( Bspec[j], spec[1] );
 230          Bcolor[j][3] = sumA[1];
 231       }
 232    }
 233 }
 234
 235
 236 static void TAG(light_rgba)( GLcontext *ctx,
 237                              struct vertex_buffer *VB,
 238                              struct tnl_pipeline_stage *stage,
 239                              GLvector4f *input )
 240 {
 241    struct light_stage_data *store = LIGHT_STAGE_DATA(stage);
 242    GLuint j;
 243
 244    GLfloat (*base)[3] = ctx->Light._BaseColor;
 245    GLfloat sumA[2];
 246
 247    const GLuint vstride = input->stride;
 248    const GLfloat *vertex = (GLfloat *) input->data;
 249    const GLuint nstride = VB->NormalPtr->stride;
 250    const GLfloat *normal = (GLfloat *)VB->NormalPtr->data;
 251
 252    GLfloat (*Fcolor)[4] = (GLfloat (*)[4]) store->LitColor[0].data;
 253    GLfloat (*Bcolor)[4] = (GLfloat (*)[4]) store->LitColor[1].data;
 254    GLfloat (*color[2])[4];
 255
 256    const GLuint nr = VB->Count;
 257
 258 #ifdef TRACE
 259    fprintf(stderr, "%s\n", __FUNCTION__ );
 260 #endif
 261
 262    (void) nstride;
 263    (void) vstride;
 264
 265    color[0] = Fcolor;
 266    color[1] = Bcolor;
 267
 268    VB->ColorPtr[0] = &store->LitColor[0];
 269    sumA[0] = ctx->Light.Material.Attrib[MAT_ATTRIB_FRONT_DIFFUSE][3];
 270
 271    if (IDX & LIGHT_TWOSIDE) {
 272       VB->ColorPtr[1] = &store->LitColor[1];
 273       sumA[1] = ctx->Light.Material.Attrib[MAT_ATTRIB_BACK_DIFFUSE][3];
 274    }
 275
 276    if (stage->changed_inputs == 0)
 277       return;
 278
 279    for (j = 0; j < nr; j++,STRIDE_F(vertex,vstride),STRIDE_F(normal,nstride)) {
 280       GLfloat sum[2][3];
 281       struct gl_light *light;
 282
 283       if ( IDX & LIGHT_MATERIAL ) {
 284          update_materials( ctx, store );
 285          sumA[0] = ctx->Light.Material.Attrib[MAT_ATTRIB_FRONT_DIFFUSE][3];
 286          if (IDX & LIGHT_TWOSIDE)
 287             sumA[1] = ctx->Light.Material.Attrib[MAT_ATTRIB_BACK_DIFFUSE][3];
 288       }
 289
 290       COPY_3V(sum[0], base[0]);
 291
 292       if ( IDX & LIGHT_TWOSIDE )
 293          COPY_3V(sum[1], base[1]);
 294
 295       /* Add contribution from each enabled light source */
 296       foreach (light, &ctx->Light.EnabledList) {
 297
 298          GLfloat n_dot_h;
 299          GLfloat correction;
 300          GLint side;
 301          GLfloat contrib[3];
 302          GLfloat attenuation = 1.0;
 303          GLfloat VP[3];          /* unit vector from vertex to light */
 304          GLfloat n_dot_VP;       /* n dot VP */
 305          GLfloat *h;
 306
 307          /* compute VP and attenuation */
 308          if (!(light->_Flags & LIGHT_POSITIONAL)) {
 309             /* directional light */
 310             COPY_3V(VP, light->_VP_inf_norm);
 311             attenuation = light->_VP_inf_spot_attenuation;
 312          }
 313          else {
 314             GLfloat d;     /* distance from vertex to light */
 315
 316
 317             SUB_3V(VP, light->_Position, vertex);
 318
 319             d = (GLfloat) LEN_3FV( VP );
 320
 321             if ( d > 1e-6) {
 322                GLfloat invd = 1.0F / d;
 323                SELF_SCALE_SCALAR_3V(VP, invd);
 324             }
 325
 326             attenuation = 1.0F / (light->ConstantAttenuation + d *
 327                                   (light->LinearAttenuation + d *
 328                                    light->QuadraticAttenuation));
 329
 330             /* spotlight attenuation */
 331             if (light->_Flags & LIGHT_SPOT) {
 332                GLfloat PV_dot_dir = - DOT3(VP, light->_NormDirection);
 333
 334                if (PV_dot_dir<light->_CosCutoff) {
 335                   continue; /* this light makes no contribution */
 336                }
 337                else {
 338                   GLdouble x = PV_dot_dir * (EXP_TABLE_SIZE-1);
 339                   GLint k = (GLint) x;
 340                   GLfloat spot = (GLfloat) (light->_SpotExpTable[k][0]
 341                                   + (x-k)*light->_SpotExpTable[k][1]);
 342                   attenuation *= spot;
 343                }
 344             }
 345          }
 346
 347          if (attenuation < 1e-3)
 348             continue;           /* this light makes no contribution */
 349
 350          /* Compute dot product or normal and vector from V to light pos */
 351          n_dot_VP = DOT3( normal, VP );
 352
 353          /* which side are we lighting? */
 354          if (n_dot_VP < 0.0F) {
 355             ACC_SCALE_SCALAR_3V(sum[0], attenuation, light->_MatAmbient[0]);
 356
 357             if (!(IDX & LIGHT_TWOSIDE))
 358                continue;
 359
 360             side = 1;
 361             correction = -1;
 362             n_dot_VP = -n_dot_VP;
 363          }
 364          else {
 365             if (IDX & LIGHT_TWOSIDE) {
 366                ACC_SCALE_SCALAR_3V( sum[1], attenuation, light->_MatAmbient[1]);
 367             }
 368             side = 0;
 369             correction = 1;
 370          }
 371
 372          COPY_3V(contrib, light->_MatAmbient[side]);
 373
 374          /* diffuse term */
 375          ACC_SCALE_SCALAR_3V(contrib, n_dot_VP, light->_MatDiffuse[side]);
 376
 377          /* specular term - cannibalize VP... */
 378          {
 379             if (ctx->Light.Model.LocalViewer) {
 380                GLfloat v[3];
 381                COPY_3V(v, vertex);
 382                NORMALIZE_3FV(v);
 383                SUB_3V(VP, VP, v);                /* h = VP + VPe */
 384                h = VP;
 385                NORMALIZE_3FV(h);
 386             }
 387             else if (light->_Flags & LIGHT_POSITIONAL) {
 388                h = VP;
 389                ACC_3V(h, ctx->_EyeZDir);
 390                NORMALIZE_3FV(h);
 391             }
 392             else {
 393                h = light->_h_inf_norm;
 394             }
 395
 396             n_dot_h = correction * DOT3(normal, h);
 397
 398             if (n_dot_h > 0.0F)
 399             {
 400                GLfloat spec_coef;
 401                struct gl_shine_tab *tab = ctx->_ShineTable[side];
 402
 403                GET_SHINE_TAB_ENTRY( tab, n_dot_h, spec_coef );
 404
 405                ACC_SCALE_SCALAR_3V( contrib, spec_coef,
 406                                     light->_MatSpecular[side]);
 407             }
 408          }
 409
 410          ACC_SCALE_SCALAR_3V( sum[side], attenuation, contrib );
 411       }
 412
 413       COPY_3V( Fcolor[j], sum[0] );
 414       Fcolor[j][3] = sumA[0];
 415
 416       if (IDX & LIGHT_TWOSIDE) {
 417          COPY_3V( Bcolor[j], sum[1] );
 418          Bcolor[j][3] = sumA[1];
 419       }
 420    }
 421 }
 422
 423
 424
 425
 426 /* As below, but with just a single light.
 427  */
 428 static void TAG(light_fast_rgba_single)( GLcontext *ctx,
 429                                          struct vertex_buffer *VB,
 430                                          struct tnl_pipeline_stage *stage,
 431                                          GLvector4f *input )
 432
 433 {
 434    struct light_stage_data *store = LIGHT_STAGE_DATA(stage);
 435    const GLuint nstride = VB->NormalPtr->stride;
 436    const GLfloat *normal = (GLfloat *)VB->NormalPtr->data;
 437    GLfloat (*Fcolor)[4] = (GLfloat (*)[4]) store->LitColor[0].data;
 438    GLfloat (*Bcolor)[4] = (GLfloat (*)[4]) store->LitColor[1].data;
 439    const struct gl_light *light = ctx->Light.EnabledList.next;
 440    GLuint j = 0;
 441    GLfloat base[2][3];
 442    const GLuint nr = VB->Count;
 443
 444 #ifdef TRACE
 445    fprintf(stderr, "%s\n", __FUNCTION__ );
 446 #endif
 447
 448    (void) input;                /* doesn't refer to Eye or Obj */
 449    (void) nr;
 450    (void) nstride;
 451
 452    VB->ColorPtr[0] = &store->LitColor[0];
 453    if (IDX & LIGHT_TWOSIDE)
 454       VB->ColorPtr[1] = &store->LitColor[1];
 455
 456    if (stage->changed_inputs == 0)
 457       return;
 458
 459    for (j = 0; j < nr; j++, STRIDE_F(normal,nstride)) {
 460
 461       GLfloat n_dot_VP;
 462
 463       if ( IDX & LIGHT_MATERIAL )
 464          update_materials( ctx, store );
 465
 466       /* No attenuation, so incoporate _MatAmbient into base color.
 467        */
 468       if ( j == 0 || (IDX & LIGHT_MATERIAL) ) {
 469          COPY_3V(base[0], light->_MatAmbient[0]);
 470          ACC_3V(base[0], ctx->Light._BaseColor[0] );
 471          base[0][3] = ctx->Light.Material.Attrib[MAT_ATTRIB_FRONT_DIFFUSE][3];
 472
 473          if (IDX & LIGHT_TWOSIDE) {
 474             COPY_3V(base[1], light->_MatAmbient[1]);
 475             ACC_3V(base[1], ctx->Light._BaseColor[1]);
 476             base[1][3] = ctx->Light.Material.Attrib[MAT_ATTRIB_BACK_DIFFUSE][3];
 477          }
 478       }
 479
 480       n_dot_VP = DOT3(normal, light->_VP_inf_norm);
 481
 482       if (n_dot_VP < 0.0F) {
 483          if (IDX & LIGHT_TWOSIDE) {
 484             GLfloat n_dot_h = -DOT3(normal, light->_h_inf_norm);
 485             GLfloat sum[3];
 486             COPY_3V(sum, base[1]);
 487             ACC_SCALE_SCALAR_3V(sum, -n_dot_VP, light->_MatDiffuse[1]);
 488             if (n_dot_h > 0.0F) {
 489                GLfloat spec;
 490                GET_SHINE_TAB_ENTRY( ctx->_ShineTable[1], n_dot_h, spec );
 491                ACC_SCALE_SCALAR_3V(sum, spec, light->_MatSpecular[1]);
 492             }
 493             COPY_3V(Bcolor[j], sum );
 494             Bcolor[j][3] = base[1][3];
 495          }
 496          COPY_4FV(Fcolor[j], base[0]);
 497       }
 498       else {
 499          GLfloat n_dot_h = DOT3(normal, light->_h_inf_norm);
 500          GLfloat sum[3];
 501          COPY_3V(sum, base[0]);
 502          ACC_SCALE_SCALAR_3V(sum, n_dot_VP, light->_MatDiffuse[0]);
 503          if (n_dot_h > 0.0F) {
 504             GLfloat spec;
 505             GET_SHINE_TAB_ENTRY( ctx->_ShineTable[0], n_dot_h, spec );
 506             ACC_SCALE_SCALAR_3V(sum, spec, light->_MatSpecular[0]);
 507
 508          }
 509          COPY_3V(Fcolor[j], sum );
 510          Fcolor[j][3] = base[0][3];
 511          if (IDX & LIGHT_TWOSIDE) COPY_4FV(Bcolor[j], base[1]);
 512       }
 513    }
 514 }
 515
 516
 517 /* Light infinite lights
 518  */
 519 static void TAG(light_fast_rgba)( GLcontext *ctx,
 520                                   struct vertex_buffer *VB,
 521                                   struct tnl_pipeline_stage *stage,
 522                                   GLvector4f *input )
 523 {
 524    struct light_stage_data *store = LIGHT_STAGE_DATA(stage);
 525    GLfloat sumA[2];
 526    const GLuint nstride = VB->NormalPtr->stride;
 527    const GLfloat *normal = (GLfloat *)VB->NormalPtr->data;
 528    GLfloat (*Fcolor)[4] = (GLfloat (*)[4]) store->LitColor[0].data;
 529    GLfloat (*Bcolor)[4] = (GLfloat (*)[4]) store->LitColor[1].data;
 530    GLuint j = 0;
 531    const GLuint nr = VB->Count;
 532    const struct gl_light *light;
 533
 534 #ifdef TRACE
 535    fprintf(stderr, "%s %d\n", __FUNCTION__, nr );
 536 #endif
 537
 538    (void) input;
 539    (void) nr;
 540    (void) nstride;
 541
 542    sumA[0] = ctx->Light.Material.Attrib[MAT_ATTRIB_FRONT_DIFFUSE][3];
 543    sumA[1] = ctx->Light.Material.Attrib[MAT_ATTRIB_BACK_DIFFUSE][3];
 544
 545    VB->ColorPtr[0] = &store->LitColor[0];
 546    if (IDX & LIGHT_TWOSIDE)
 547       VB->ColorPtr[1] = &store->LitColor[1];
 548
 549    if (stage->changed_inputs == 0)
 550       return;
 551
 552    for (j = 0; j < nr; j++, STRIDE_F(normal,nstride)) {
 553
 554       GLfloat sum[2][3];
 555
 556       if ( IDX & LIGHT_MATERIAL ) {
 557          update_materials( ctx, store );
 558
 559          sumA[0] = ctx->Light.Material.Attrib[MAT_ATTRIB_FRONT_DIFFUSE][3];
 560          if (IDX & LIGHT_TWOSIDE)
 561             sumA[1] = ctx->Light.Material.Attrib[MAT_ATTRIB_BACK_DIFFUSE][3];
 562       }
 563
 564
 565       COPY_3V(sum[0], ctx->Light._BaseColor[0]);
 566       if (IDX & LIGHT_TWOSIDE)
 567          COPY_3V(sum[1], ctx->Light._BaseColor[1]);
 568
 569       foreach (light, &ctx->Light.EnabledList) {
 570          GLfloat n_dot_h, n_dot_VP, spec;
 571
 572          ACC_3V(sum[0], light->_MatAmbient[0]);
 573          if (IDX & LIGHT_TWOSIDE)
 574             ACC_3V(sum[1], light->_MatAmbient[1]);
 575
 576          n_dot_VP = DOT3(normal, light->_VP_inf_norm);
 577
 578          if (n_dot_VP > 0.0F) {
 579             ACC_SCALE_SCALAR_3V(sum[0], n_dot_VP, light->_MatDiffuse[0]);
 580             n_dot_h = DOT3(normal, light->_h_inf_norm);
 581             if (n_dot_h > 0.0F) {
 582                struct gl_shine_tab *tab = ctx->_ShineTable[0];
 583                GET_SHINE_TAB_ENTRY( tab, n_dot_h, spec );
 584                ACC_SCALE_SCALAR_3V( sum[0], spec, light->_MatSpecular[0]);
 585             }
 586          }
 587          else if (IDX & LIGHT_TWOSIDE) {
 588             ACC_SCALE_SCALAR_3V(sum[1], -n_dot_VP, light->_MatDiffuse[1]);
 589             n_dot_h = -DOT3(normal, light->_h_inf_norm);
 590             if (n_dot_h > 0.0F) {
 591                struct gl_shine_tab *tab = ctx->_ShineTable[1];
 592                GET_SHINE_TAB_ENTRY( tab, n_dot_h, spec );
 593                ACC_SCALE_SCALAR_3V( sum[1], spec, light->_MatSpecular[1]);
 594             }
 595          }
 596       }
 597
 598       COPY_3V( Fcolor[j], sum[0] );
 599       Fcolor[j][3] = sumA[0];
 600
 601       if (IDX & LIGHT_TWOSIDE) {
 602          COPY_3V( Bcolor[j], sum[1] );
 603          Bcolor[j][3] = sumA[1];
 604       }
 605    }
 606 }
 607
 608
 609
 610
 611
 612 /*
 613  * Use current lighting/material settings to compute the color indexes
 614  * for an array of vertices.
 615  * Input:  n - number of vertices to light
 616  *         side - 0=use front material, 1=use back material
 617  *         vertex - array of [n] vertex position in eye coordinates
 618  *         normal - array of [n] surface normal vector
 619  * Output:  indexResult - resulting array of [n] color indexes
 620  */
 621 static void TAG(light_ci)( GLcontext *ctx,
 622                            struct vertex_buffer *VB,
 623                            struct tnl_pipeline_stage *stage,
 624                            GLvector4f *input )
 625 {
 626    struct light_stage_data *store = LIGHT_STAGE_DATA(stage);
 627    GLuint j;
 628    const GLuint vstride = input->stride;
 629    const GLfloat *vertex = (GLfloat *) input->data;
 630    const GLuint nstride = VB->NormalPtr->stride;
 631    const GLfloat *normal = (GLfloat *)VB->NormalPtr->data;
 632    GLfloat *indexResult[2];
 633    const GLuint nr = VB->Count;
 634
 635 #ifdef TRACE
 636    fprintf(stderr, "%s\n", __FUNCTION__ );
 637 #endif
 638
 639    (void) nstride;
 640    (void) vstride;
 641
 642    VB->IndexPtr[0] = &store->LitIndex[0];
 643    if (IDX & LIGHT_TWOSIDE)
 644       VB->IndexPtr[1] = &store->LitIndex[1];
 645
 646    if (stage->changed_inputs == 0)
 647       return;
 648
 649    indexResult[0] = (GLfloat *)VB->IndexPtr[0]->data;
 650    if (IDX & LIGHT_TWOSIDE)
 651       indexResult[1] = (GLfloat *)VB->IndexPtr[1]->data;
 652
 653    /* loop over vertices */
 654    for (j=0; j<nr; j++,STRIDE_F(vertex,vstride),STRIDE_F(normal, nstride)) {
 655       GLfloat diffuse[2], specular[2];
 656       GLuint side = 0;
 657       struct gl_light *light;
 658
 659       if ( IDX & LIGHT_MATERIAL )
 660          update_materials( ctx, store );
 661
 662       diffuse[0] = specular[0] = 0.0F;
 663
 664       if ( IDX & LIGHT_TWOSIDE ) {
 665          diffuse[1] = specular[1] = 0.0F;
 666       }
 667
 668       /* Accumulate diffuse and specular from each light source */
 669       foreach (light, &ctx->Light.EnabledList) {
 670
 671          GLfloat attenuation = 1.0F;
 672          GLfloat VP[3];  /* unit vector from vertex to light */
 673          GLfloat n_dot_VP;  /* dot product of l and n */
 674          GLfloat *h, n_dot_h, correction = 1.0;
 675
 676          /* compute l and attenuation */
 677          if (!(light->_Flags & LIGHT_POSITIONAL)) {
 678             /* directional light */
 679             COPY_3V(VP, light->_VP_inf_norm);
 680          }
 681          else {
 682             GLfloat d;     /* distance from vertex to light */
 683
 684             SUB_3V(VP, light->_Position, vertex);
 685
 686             d = (GLfloat) LEN_3FV( VP );
 687             if ( d > 1e-6) {
 688                GLfloat invd = 1.0F / d;
 689                SELF_SCALE_SCALAR_3V(VP, invd);
 690             }
 691
 692             attenuation = 1.0F / (light->ConstantAttenuation + d *
 693                                   (light->LinearAttenuation + d *
 694                                    light->QuadraticAttenuation));
 695
 696             /* spotlight attenuation */
 697             if (light->_Flags & LIGHT_SPOT) {
 698                GLfloat PV_dot_dir = - DOT3(VP, light->_NormDirection);
 699                if (PV_dot_dir < light->_CosCutoff) {
 700                   continue; /* this light makes no contribution */
 701                }
 702                else {
 703                   GLdouble x = PV_dot_dir * (EXP_TABLE_SIZE-1);
 704                   GLint k = (GLint) x;
 705                   GLfloat spot = (GLfloat) (light->_SpotExpTable[k][0]
 706                                   + (x-k)*light->_SpotExpTable[k][1]);
 707                   attenuation *= spot;
 708                }
 709             }
 710          }
 711
 712          if (attenuation < 1e-3)
 713             continue;           /* this light makes no contribution */
 714
 715          n_dot_VP = DOT3( normal, VP );
 716
 717          /* which side are we lighting? */
 718          if (n_dot_VP < 0.0F) {
 719             if (!(IDX & LIGHT_TWOSIDE))
 720                continue;
 721             side = 1;
 722             correction = -1;
 723             n_dot_VP = -n_dot_VP;
 724          }
 725
 726          /* accumulate diffuse term */
 727          diffuse[side] += n_dot_VP * light->_dli * attenuation;
 728
 729          /* specular term */
 730          if (ctx->Light.Model.LocalViewer) {
 731             GLfloat v[3];
 732             COPY_3V(v, vertex);
 733             NORMALIZE_3FV(v);
 734             SUB_3V(VP, VP, v);                /* h = VP + VPe */
 735             h = VP;
 736             NORMALIZE_3FV(h);
 737          }
 738          else if (light->_Flags & LIGHT_POSITIONAL) {
 739             h = VP;
 740             /* Strangely, disabling this addition fixes a conformance
 741              * problem.  If this code is enabled, l_sed.c fails.
 742              */
 743             /*ACC_3V(h, ctx->_EyeZDir);*/
 744             NORMALIZE_3FV(h);
 745          }
 746          else {
 747             h = light->_h_inf_norm;
 748          }
 749
 750          n_dot_h = correction * DOT3(normal, h);
 751          if (n_dot_h > 0.0F) {
 752             GLfloat spec_coef;
 753             struct gl_shine_tab *tab = ctx->_ShineTable[side];
 754             GET_SHINE_TAB_ENTRY( tab, n_dot_h, spec_coef);
 755             specular[side] += spec_coef * light->_sli * attenuation;
 756          }
 757       } /*loop over lights*/
 758
 759       /* Now compute final color index */
 760       for (side = 0 ; side < NR_SIDES ; side++) {
 761          const GLfloat *ind = ctx->Light.Material.Attrib[MAT_ATTRIB_FRONT_INDEXES + side];
 762          GLfloat index;
 763
 764          if (specular[side] > 1.0F) {
 765             index = ind[MAT_INDEX_SPECULAR];
 766          }
 767          else {
 768             GLfloat d_a = ind[MAT_INDEX_DIFFUSE] - ind[MAT_INDEX_AMBIENT];
 769             GLfloat s_a = ind[MAT_INDEX_SPECULAR] - ind[MAT_INDEX_AMBIENT];
 770             index = (ind[MAT_INDEX_AMBIENT]
 771                      + diffuse[side] * (1.0F-specular[side]) * d_a
 772                      + specular[side] * s_a);
 773             if (index > ind[MAT_INDEX_SPECULAR]) {
 774                index = ind[MAT_INDEX_SPECULAR];
 775             }
 776          }
 777          indexResult[side][j] = index;
 778       }
 779    } /*for vertex*/
 780 }
 781
 782
 783
 784 static void TAG(init_light_tab)( void )
 785 {
 786    _tnl_light_tab[IDX] = TAG(light_rgba);
 787    _tnl_light_fast_tab[IDX] = TAG(light_fast_rgba);
 788    _tnl_light_fast_single_tab[IDX] = TAG(light_fast_rgba_single);
 789    _tnl_light_spec_tab[IDX] = TAG(light_rgba_spec);
 790    _tnl_light_ci_tab[IDX] = TAG(light_ci);
 791 }
 792
 793
 794 #undef TAG
 795 #undef IDX
 796 #undef NR_SIDES