| 1 | greg | 1.1 | /* Copyright (c) 1991 Regents of the University of California */ | 
| 2 |  |  |  | 
| 3 |  |  | #ifndef lint | 
| 4 |  |  | static char SCCSid[] = "$SunId$ LBL"; | 
| 5 |  |  | #endif | 
| 6 |  |  |  | 
| 7 |  |  | /* | 
| 8 |  |  | * Routines for simulating virtual light sources | 
| 9 |  |  | *      Thus far, we only support planar mirrors. | 
| 10 |  |  | */ | 
| 11 |  |  |  | 
| 12 |  |  | #include  "ray.h" | 
| 13 |  |  |  | 
| 14 |  |  | #include  "source.h" | 
| 15 |  |  |  | 
| 16 |  |  | #include  "otypes.h" | 
| 17 |  |  |  | 
| 18 |  |  | #include  "cone.h" | 
| 19 |  |  |  | 
| 20 |  |  | #include  "face.h" | 
| 21 |  |  |  | 
| 22 |  |  | extern int  directrelay;                /* maximum number of source relays */ | 
| 23 |  |  |  | 
| 24 |  |  | double  getplaneq(); | 
| 25 |  |  | double  getmaxdisk(); | 
| 26 |  |  | double  intercircle(); | 
| 27 |  |  | SRCREC  *makevsrc(); | 
| 28 |  |  |  | 
| 29 |  |  | static OBJECT  *vobject;                /* virtual source objects */ | 
| 30 |  |  | static int  nvobjects = 0;              /* number of virtual source objects */ | 
| 31 |  |  |  | 
| 32 |  |  |  | 
| 33 |  |  | markvirtuals()                  /* find and mark virtual sources */ | 
| 34 |  |  | { | 
| 35 |  |  | register OBJREC  *o; | 
| 36 |  |  | register int  i; | 
| 37 |  |  | /* check number of direct relays */ | 
| 38 |  |  | if (directrelay <= 0) | 
| 39 |  |  | return; | 
| 40 |  |  | /* find virtual source objects */ | 
| 41 |  |  | for (i = 0; i < nobjects; i++) { | 
| 42 |  |  | o = objptr(i); | 
| 43 |  |  | if (o->omod == OVOID) | 
| 44 |  |  | continue; | 
| 45 |  |  | if (!isvlight(objptr(o->omod)->otype)) | 
| 46 |  |  | continue; | 
| 47 |  |  | if (nvobjects == 0) | 
| 48 |  |  | vobject = (OBJECT *)malloc(sizeof(OBJECT)); | 
| 49 |  |  | else | 
| 50 |  |  | vobject = (OBJECT *)realloc((char *)vobject, | 
| 51 |  |  | (unsigned)(nvobjects+1)*sizeof(OBJECT)); | 
| 52 |  |  | if (vobject == NULL) | 
| 53 |  |  | error(SYSTEM, "out of memory in addvirtuals"); | 
| 54 |  |  | vobject[nvobjects++] = i; | 
| 55 |  |  | } | 
| 56 |  |  | if (nvobjects == 0) | 
| 57 |  |  | return; | 
| 58 |  |  | /* append virtual sources */ | 
| 59 |  |  | for (i = nsources; i-- > 0; ) | 
| 60 |  |  | if (!(source[i].sflags & SSKIP)) | 
| 61 |  |  | addvirtuals(&source[i], directrelay); | 
| 62 |  |  | /* done with our object list */ | 
| 63 |  |  | free((char *)vobject); | 
| 64 |  |  | nvobjects = 0; | 
| 65 |  |  | } | 
| 66 |  |  |  | 
| 67 |  |  |  | 
| 68 |  |  | addvirtuals(sr, nr)             /* add virtual sources associated with sr */ | 
| 69 |  |  | SRCREC  *sr; | 
| 70 |  |  | int  nr; | 
| 71 |  |  | { | 
| 72 |  |  | register int  i; | 
| 73 |  |  | /* check relay limit first */ | 
| 74 |  |  | if (nr <= 0) | 
| 75 |  |  | return; | 
| 76 |  |  | /* check each virtual object for projection */ | 
| 77 |  |  | for (i = 0; i < nvobjects; i++) | 
| 78 |  |  | vproject(objptr(i), sr, nr-1);  /* calls us recursively */ | 
| 79 |  |  | } | 
| 80 |  |  |  | 
| 81 |  |  |  | 
| 82 |  |  | SRCREC * | 
| 83 |  |  | makevsrc(op, sp, pm)            /* make virtual source if reasonable */ | 
| 84 |  |  | OBJREC  *op; | 
| 85 |  |  | register SRCREC  *sp; | 
| 86 |  |  | MAT4  pm; | 
| 87 |  |  | { | 
| 88 |  |  | register SRCREC  *newsrc; | 
| 89 |  |  | FVECT  nsloc, ocent, nsnorm; | 
| 90 |  |  | double  maxrad2; | 
| 91 |  |  | double  d1, d2; | 
| 92 |  |  | SPOT  theirspot, ourspot; | 
| 93 |  |  | register int  i; | 
| 94 |  |  | /* get object center and max. radius */ | 
| 95 |  |  | maxrad2 = getmaxdisk(ocent, op); | 
| 96 |  |  | if (maxrad2 <= FTINY)                   /* too small? */ | 
| 97 |  |  | return(NULL); | 
| 98 |  |  | /* get location and spot */ | 
| 99 |  |  | if (sp->sflags & SDISTANT) {            /* distant source */ | 
| 100 |  |  | if (sp->sflags & SPROX) | 
| 101 |  |  | return(NULL);           /* should never get here! */ | 
| 102 |  |  | multv3(nsloc, sp->sloc, pm); | 
| 103 |  |  | VCOPY(ourspot.aim, ocent); | 
| 104 |  |  | ourspot.siz = PI*maxrad2; | 
| 105 |  |  | ourspot.flen = 0.; | 
| 106 |  |  | if (sp->sflags & SSPOT) { | 
| 107 |  |  | copystruct(&theirspot, sp->sl.s); | 
| 108 |  |  | multp3(theirspot.aim, sp->sl.s->aim, pm); | 
| 109 |  |  | if (!commonbeam(&ourspot, &theirspot, nsloc)) | 
| 110 |  |  | return(NULL);           /* no overlap */ | 
| 111 |  |  | } | 
| 112 |  |  | } else {                                /* local source */ | 
| 113 |  |  | multp3(nsloc, sp->sloc, pm); | 
| 114 |  |  | if (sp->sflags & SPROX) { | 
| 115 |  |  | d2 = 0.; | 
| 116 |  |  | for (i = 0; i < 3; i++) { | 
| 117 |  |  | d1 = ocent[i] - nsloc[i]; | 
| 118 |  |  | d2 += d1*d1; | 
| 119 |  |  | } | 
| 120 |  |  | if (d2 > sp->sl.prox*sp->sl.prox) | 
| 121 |  |  | return(NULL);   /* too far away */ | 
| 122 |  |  | } | 
| 123 |  |  | for (i = 0; i < 3; i++) | 
| 124 |  |  | ourspot.aim[i] = ocent[i] - nsloc[i]; | 
| 125 |  |  | if ((d1 = normalize(ourspot.aim)) == 0.) | 
| 126 |  |  | return(NULL);           /* at source!! */ | 
| 127 |  |  | ourspot.siz = 2.*PI*(1. - d1/sqrt(d1*d1+maxrad2)); | 
| 128 |  |  | ourspot.flen = 0.; | 
| 129 |  |  | if (sp->sflags & SSPOT) { | 
| 130 |  |  | copystruct(&theirspot, sp->sl.s); | 
| 131 |  |  | multv3(theirspot.aim, sp->sl.s->aim, pm); | 
| 132 |  |  | if (!commonspot(&ourspot, &theirspot, nsloc)) | 
| 133 |  |  | return(NULL);           /* no overlap */ | 
| 134 |  |  | ourspot.flen = theirspot.flen; | 
| 135 |  |  | } | 
| 136 |  |  | if (sp->sflags & SFLAT) {       /* check for behind source */ | 
| 137 |  |  | multv3(nsnorm, sp->snorm, pm); | 
| 138 |  |  | if (checkspot(&ourspot, nsnorm) < 0) | 
| 139 |  |  | return(NULL); | 
| 140 |  |  | } | 
| 141 |  |  | } | 
| 142 |  |  | /* everything is OK, make source */ | 
| 143 |  |  | if ((newsrc = newsource()) == NULL) | 
| 144 |  |  | goto memerr; | 
| 145 |  |  | newsrc->sflags = sp->sflags | (SVIRTUAL|SSPOT|SFOLLOW); | 
| 146 |  |  | VCOPY(newsrc->sloc, nsloc); | 
| 147 |  |  | if (newsrc->sflags & SFLAT) | 
| 148 |  |  | VCOPY(newsrc->snorm, nsnorm); | 
| 149 |  |  | newsrc->ss = sp->ss; newsrc->ss2 = sp->ss2; | 
| 150 |  |  | if ((newsrc->sl.s = (SPOT *)malloc(sizeof(SPOT))) == NULL) | 
| 151 |  |  | goto memerr; | 
| 152 |  |  | copystruct(newsrc->sl.s, &ourspot); | 
| 153 |  |  | if (newsrc->sflags & SPROX) | 
| 154 |  |  | newsrc->sl.prox = sp->sl.prox; | 
| 155 |  |  | newsrc->sa.svnext = sp - source; | 
| 156 |  |  | return(newsrc); | 
| 157 |  |  | memerr: | 
| 158 |  |  | error(SYSTEM, "out of memory in makevsrc"); | 
| 159 |  |  | } | 
| 160 |  |  |  | 
| 161 |  |  |  | 
| 162 |  |  | commonspot(sp1, sp2, org)       /* set sp1 to intersection of sp1 and sp2 */ | 
| 163 |  |  | register SPOT  *sp1, *sp2; | 
| 164 |  |  | FVECT  org; | 
| 165 |  |  | { | 
| 166 |  |  | FVECT  cent; | 
| 167 |  |  | double  rad2, d1r2, d2r2; | 
| 168 |  |  |  | 
| 169 |  |  | d1r2 = 1. - sp1->siz/(2.*PI); | 
| 170 |  |  | d2r2 = 1. - sp2->siz/(2.*PI); | 
| 171 |  |  | if (sp2->siz >= 2.*PI-FTINY)            /* BIG, just check overlap */ | 
| 172 |  |  | return(DOT(sp1->aim,sp2->aim) >= d1r2*d2r2 - | 
| 173 |  |  | sqrt((1.-d1r2*d1r2)*(1.-d2r2*d2r2))); | 
| 174 |  |  | /* compute and check disks */ | 
| 175 |  |  | d1r2 = 1./(d1r2*d1r2) - 1.; | 
| 176 |  |  | d2r2 = 1./(d2r2*d2r2) - 1.; | 
| 177 |  |  | rad2 = intercircle(cent, sp1->aim, sp2->aim, d1r2, d2r2); | 
| 178 |  |  | if (rad2 <= FTINY || normalize(cent) == 0.) | 
| 179 |  |  | return(0); | 
| 180 |  |  | VCOPY(sp1->aim, cent); | 
| 181 |  |  | sp1->siz = 2.*PI*(1. - 1./sqrt(1.+rad2)); | 
| 182 |  |  | return(1); | 
| 183 |  |  | } | 
| 184 |  |  |  | 
| 185 |  |  |  | 
| 186 |  |  | commonbeam(sp1, sp2, dir)       /* set sp1 to intersection of sp1 and sp2 */ | 
| 187 |  |  | register SPOT  *sp1, *sp2; | 
| 188 |  |  | FVECT  dir; | 
| 189 |  |  | { | 
| 190 |  |  | FVECT  cent, c1, c2; | 
| 191 |  |  | double  rad2, d; | 
| 192 |  |  | register int  i; | 
| 193 |  |  | /* move centers to common plane */ | 
| 194 |  |  | d = DOT(sp1->aim, dir); | 
| 195 |  |  | for (i = 0; i < 3; i++) | 
| 196 |  |  | c1[i] = sp2->aim[i] - d*dir[i]; | 
| 197 |  |  | d = DOT(sp2->aim, dir); | 
| 198 |  |  | for (i = 0; i < 3; i++) | 
| 199 |  |  | c2[i] = sp2->aim[i] - d*dir[i]; | 
| 200 |  |  | /* compute overlap */ | 
| 201 |  |  | rad2 = intercircle(cent, c1, c2, sp1->siz/PI, sp2->siz/PI); | 
| 202 |  |  | if (rad2 <= FTINY) | 
| 203 |  |  | return(0); | 
| 204 |  |  | VCOPY(sp1->aim, cent); | 
| 205 |  |  | sp1->siz = PI*rad2; | 
| 206 |  |  | return(1); | 
| 207 |  |  | } | 
| 208 |  |  |  | 
| 209 |  |  |  | 
| 210 |  |  | checkspot(sp, nrm)              /* check spotlight for behind source */ | 
| 211 |  |  | register SPOT  *sp; | 
| 212 |  |  | FVECT  nrm; | 
| 213 |  |  | { | 
| 214 |  |  | double  d, d1; | 
| 215 |  |  |  | 
| 216 |  |  | d = DOT(sp->aim, nrm); | 
| 217 |  |  | if (d > FTINY)                  /* center in front? */ | 
| 218 |  |  | return(0); | 
| 219 |  |  | /* else check horizon */ | 
| 220 |  |  | d1 = 1. - sp->siz/(2.*PI); | 
| 221 |  |  | return(1.-FTINY-d*d > d1*d1); | 
| 222 |  |  | } | 
| 223 |  |  |  | 
| 224 |  |  |  | 
| 225 |  |  | mirrorproj(m, nv, offs)         /* get mirror projection for surface */ | 
| 226 |  |  | register MAT4  m; | 
| 227 |  |  | FVECT  nv; | 
| 228 |  |  | double  offs; | 
| 229 |  |  | { | 
| 230 |  |  | register int  i, j; | 
| 231 |  |  | /* assign matrix */ | 
| 232 |  |  | setident4(m); | 
| 233 |  |  | for (i = 0; i < 3; i++) | 
| 234 |  |  | for (j = 0; j < 3; j++) | 
| 235 |  |  | m[i][j] -= 2.*nv[i]*nv[j]; | 
| 236 |  |  | for (j = 0; j < 3; j++) | 
| 237 |  |  | m[3][j] = 2.*offs*nv[j]; | 
| 238 |  |  | } | 
| 239 |  |  |  | 
| 240 |  |  |  | 
| 241 |  |  | double | 
| 242 |  |  | intercircle(cc, c1, c2, r1s, r2s)       /* intersect two circles */ | 
| 243 |  |  | FVECT  cc;                      /* midpoint (return value) */ | 
| 244 |  |  | FVECT  c1, c2;                  /* circle centers */ | 
| 245 |  |  | double  r1s, r2s;               /* radii squared */ | 
| 246 |  |  | { | 
| 247 |  |  | double  a2, d2, l; | 
| 248 |  |  | FVECT  disp; | 
| 249 |  |  | register int  i; | 
| 250 |  |  |  | 
| 251 |  |  | for (i = 0; i < 3; i++) | 
| 252 |  |  | disp[i] = c2[i] - c1[i]; | 
| 253 |  |  | d2 = DOT(disp,disp); | 
| 254 |  |  | /* circle within overlap? */ | 
| 255 |  |  | if (r1s < r2s) { | 
| 256 |  |  | if (r2s >= r1s + d2) { | 
| 257 |  |  | VCOPY(cc, c1); | 
| 258 |  |  | return(r1s); | 
| 259 |  |  | } | 
| 260 |  |  | } else { | 
| 261 |  |  | if (r1s >= r2s + d2) { | 
| 262 |  |  | VCOPY(cc, c2); | 
| 263 |  |  | return(r2s); | 
| 264 |  |  | } | 
| 265 |  |  | } | 
| 266 |  |  | a2 = .25*(2.*(r1s+r2s) - d2 - (r2s-r1s)*(r2s-r1s)/d2); | 
| 267 |  |  | /* no overlap? */ | 
| 268 |  |  | if (a2 <= 0.) | 
| 269 |  |  | return(0.); | 
| 270 |  |  | l = sqrt((r1s - a2)/d2); | 
| 271 |  |  | for (i = 0; i < 3; i++) | 
| 272 |  |  | cc[i] = c1[i] + l*disp[i]; | 
| 273 |  |  | return(a2); | 
| 274 |  |  | } | 
| 275 |  |  |  | 
| 276 |  |  |  | 
| 277 |  |  | /* | 
| 278 |  |  | * The following routines depend on the supported OBJECTS: | 
| 279 |  |  | */ | 
| 280 |  |  |  | 
| 281 |  |  |  | 
| 282 |  |  | double | 
| 283 |  |  | getmaxdisk(ocent, op)           /* get object center and squared radius */ | 
| 284 |  |  | FVECT  ocent; | 
| 285 |  |  | register OBJREC  *op; | 
| 286 |  |  | { | 
| 287 |  |  | double  maxrad2; | 
| 288 |  |  |  | 
| 289 |  |  | switch (op->otype) { | 
| 290 |  |  | case OBJ_FACE: | 
| 291 |  |  | { | 
| 292 |  |  | double  d1, d2; | 
| 293 |  |  | register int  i, j; | 
| 294 |  |  | register FACE  *f = getface(op); | 
| 295 |  |  |  | 
| 296 |  |  | for (i = 0; i < 3; i++) { | 
| 297 |  |  | ocent[i] = 0.; | 
| 298 |  |  | for (j = 0; j < f->nv; j++) | 
| 299 |  |  | ocent[i] += VERTEX(f,j)[i]; | 
| 300 |  |  | ocent[i] /= (double)f->nv; | 
| 301 |  |  | } | 
| 302 |  |  | maxrad2 = 0.; | 
| 303 |  |  | for (j = 0; j < f->nv; j++) { | 
| 304 |  |  | d2 = 0.; | 
| 305 |  |  | for (i = 0; i < 3; i++) { | 
| 306 |  |  | d1 = VERTEX(f,j)[i] - ocent[i]; | 
| 307 |  |  | d2 += d1*d1; | 
| 308 |  |  | } | 
| 309 |  |  | if (d2 > maxrad2) | 
| 310 |  |  | maxrad2 = d2; | 
| 311 |  |  | } | 
| 312 |  |  | } | 
| 313 |  |  | return(maxrad2); | 
| 314 |  |  | case OBJ_RING: | 
| 315 |  |  | { | 
| 316 |  |  | register CONE  *co = getcone(op, 0); | 
| 317 |  |  |  | 
| 318 |  |  | VCOPY(ocent, CO_P0(co)); | 
| 319 |  |  | maxrad2 = CO_R1(co); | 
| 320 |  |  | maxrad2 *= maxrad2; | 
| 321 |  |  | } | 
| 322 |  |  | return(maxrad2); | 
| 323 |  |  | } | 
| 324 |  |  | objerror(op, USER, "illegal material"); | 
| 325 |  |  | } | 
| 326 |  |  |  | 
| 327 |  |  |  | 
| 328 |  |  | double | 
| 329 |  |  | getplaneq(nvec, op)                     /* get plane equation for object */ | 
| 330 |  |  | FVECT  nvec; | 
| 331 |  |  | OBJREC  *op; | 
| 332 |  |  | { | 
| 333 |  |  | register FACE  *fo; | 
| 334 |  |  | register CONE  *co; | 
| 335 |  |  |  | 
| 336 |  |  | switch (op->otype) { | 
| 337 |  |  | case OBJ_FACE: | 
| 338 |  |  | fo = getface(op); | 
| 339 |  |  | VCOPY(nvec, fo->norm); | 
| 340 |  |  | return(fo->offset); | 
| 341 |  |  | case OBJ_RING: | 
| 342 |  |  | co = getcone(op, 0); | 
| 343 |  |  | VCOPY(nvec, co->ad); | 
| 344 |  |  | return(DOT(nvec, CO_P0(co))); | 
| 345 |  |  | } | 
| 346 |  |  | objerror(op, USER, "illegal material"); | 
| 347 |  |  | } | 
| 348 |  |  |  | 
| 349 |  |  |  | 
| 350 |  |  | /* | 
| 351 |  |  | * The following routines depend on the supported MATERIALS: | 
| 352 |  |  | */ | 
| 353 |  |  |  | 
| 354 |  |  |  | 
| 355 |  |  | vproject(o, s, n)               /* create projected source(s) if they exist */ | 
| 356 |  |  | OBJREC  *o; | 
| 357 |  |  | SRCREC  *s; | 
| 358 |  |  | int  n; | 
| 359 |  |  | { | 
| 360 |  |  | SRCREC  *ns; | 
| 361 |  |  | FVECT  norm; | 
| 362 |  |  | double  offset; | 
| 363 |  |  | MAT4  proj; | 
| 364 |  |  | /* get surface normal and offset */ | 
| 365 |  |  | offset = getplaneq(norm, o); | 
| 366 |  |  | switch (objptr(o->omod)->otype) { | 
| 367 |  |  | case MAT_MIRROR:                        /* mirror source */ | 
| 368 |  |  | if (DOT(s->sloc, norm) <= (s->sflags & SDISTANT ? | 
| 369 |  |  | FTINY : offset+FTINY)) | 
| 370 |  |  | return;                 /* behind mirror */ | 
| 371 |  |  | mirrorproj(proj, norm, offset); | 
| 372 |  |  | if ((ns = makevsrc(o, s, proj)) != NULL) | 
| 373 |  |  | addvirtuals(ns, n); | 
| 374 |  |  | break; | 
| 375 |  |  | } | 
| 376 |  |  | } | 
| 377 |  |  |  | 
| 378 |  |  |  | 
| 379 |  |  | vsrcrelay(rn, rv)               /* relay virtual source ray */ | 
| 380 |  |  | register RAY  *rn, *rv; | 
| 381 |  |  | { | 
| 382 |  |  | int  snext; | 
| 383 |  |  | register int  i; | 
| 384 |  |  | /* source we're aiming for here */ | 
| 385 |  |  | snext = source[rv->rsrc].sa.svnext; | 
| 386 |  |  | /* compute relayed ray direction */ | 
| 387 |  |  | switch (objptr(rv->ro->omod)->otype) { | 
| 388 |  |  | case MAT_MIRROR:                /* mirror: singular reflection */ | 
| 389 |  |  | rayorigin(rn, rv, REFLECTED, 1.); | 
| 390 |  |  | /* ignore textures */ | 
| 391 |  |  | for (i = 0; i < 3; i++) | 
| 392 |  |  | rn->rdir[i] = rv->rdir[i] + 2.*rv->rod*rv->ron[i]; | 
| 393 |  |  | break; | 
| 394 |  |  | #ifdef DEBUG | 
| 395 |  |  | default: | 
| 396 |  |  | error(CONSISTENCY, "inappropriate material in vsrcrelay"); | 
| 397 |  |  | #endif | 
| 398 |  |  | } | 
| 399 |  |  | rn->rsrc = snext; | 
| 400 |  |  | } | 
| 401 |  |  |  | 
| 402 |  |  |  | 
| 403 |  |  | m_mirror(m, r)                  /* shade mirrored ray */ | 
| 404 |  |  | register OBJREC  *m; | 
| 405 |  |  | register RAY  *r; | 
| 406 |  |  | { | 
| 407 |  |  | COLOR  mcolor; | 
| 408 |  |  | RAY  nr; | 
| 409 |  |  | register int  i; | 
| 410 |  |  |  | 
| 411 |  |  | if (m->oargs.nfargs != 3 || m->oargs.nsargs > 1) | 
| 412 |  |  | objerror(m, USER, "bad number of arguments"); | 
| 413 |  |  | if (r->rsrc >= 0) {                     /* aiming for somebody */ | 
| 414 |  |  | if (source[r->rsrc].so != r->ro) | 
| 415 |  |  | return;                         /* but not us */ | 
| 416 |  |  | } else if (m->oargs.nsargs > 0) {       /* else call substitute? */ | 
| 417 |  |  | rayshade(r, modifier(m->oargs.sarg[0])); | 
| 418 |  |  | return; | 
| 419 |  |  | } | 
| 420 |  |  | if (r->rod < 0.)                        /* back is black */ | 
| 421 |  |  | return; | 
| 422 |  |  | /* get modifiers */ | 
| 423 |  |  | raytexture(r, m->omod); | 
| 424 |  |  | /* assign material color */ | 
| 425 |  |  | setcolor(mcolor, m->oargs.farg[0], | 
| 426 |  |  | m->oargs.farg[1], | 
| 427 |  |  | m->oargs.farg[2]); | 
| 428 |  |  | multcolor(mcolor, r->pcol); | 
| 429 |  |  | /* compute reflected ray */ | 
| 430 |  |  | if (r->rsrc >= 0)                       /* relayed light source */ | 
| 431 |  |  | vsrcrelay(&nr, r); | 
| 432 |  |  | else {                                  /* ordinary reflection */ | 
| 433 |  |  | FVECT  pnorm; | 
| 434 |  |  | double  pdot; | 
| 435 |  |  |  | 
| 436 |  |  | if (rayorigin(&nr, r, REFLECTED, bright(mcolor)) < 0) | 
| 437 |  |  | return; | 
| 438 |  |  | pdot = raynormal(pnorm, r);     /* use textures */ | 
| 439 |  |  | for (i = 0; i < 3; i++) | 
| 440 |  |  | nr.rdir[i] = r->rdir[i] + 2.*pdot*pnorm[i]; | 
| 441 |  |  | } | 
| 442 |  |  | rayvalue(&nr); | 
| 443 |  |  | multcolor(nr.rcol, mcolor); | 
| 444 |  |  | addcolor(r->rcol, nr.rcol); | 
| 445 |  |  | } |