| 1 |
#ifndef lint |
| 2 |
static const char RCSid[] = "$Id: mkillum2.c,v 2.36 2011/08/15 19:48:06 greg Exp $"; |
| 3 |
#endif |
| 4 |
/* |
| 5 |
* Routines to do the actual calculation for mkillum |
| 6 |
*/ |
| 7 |
|
| 8 |
#include <string.h> |
| 9 |
|
| 10 |
#include "mkillum.h" |
| 11 |
#include "face.h" |
| 12 |
#include "cone.h" |
| 13 |
#include "source.h" |
| 14 |
#include "paths.h" |
| 15 |
|
| 16 |
#ifndef NBSDFSAMPS |
| 17 |
#define NBSDFSAMPS 256 /* BSDF resampling count */ |
| 18 |
#endif |
| 19 |
|
| 20 |
COLORV * distarr = NULL; /* distribution array */ |
| 21 |
int distsiz = 0; |
| 22 |
COLORV * direct_discount = NULL; /* amount to take off direct */ |
| 23 |
|
| 24 |
|
| 25 |
void |
| 26 |
newdist( /* allocate & clear distribution array */ |
| 27 |
int siz |
| 28 |
) |
| 29 |
{ |
| 30 |
if (siz <= 0) { |
| 31 |
if (distsiz > 0) |
| 32 |
free(distarr); |
| 33 |
distarr = NULL; |
| 34 |
distsiz = 0; |
| 35 |
return; |
| 36 |
} |
| 37 |
if (distsiz < siz) { |
| 38 |
if (distsiz > 0) |
| 39 |
free(distarr); |
| 40 |
distarr = (COLORV *)malloc(sizeof(COLOR)*siz); |
| 41 |
if (distarr == NULL) |
| 42 |
error(SYSTEM, "out of memory in newdist"); |
| 43 |
distsiz = siz; |
| 44 |
} |
| 45 |
memset(distarr, '\0', sizeof(COLOR)*siz); |
| 46 |
} |
| 47 |
|
| 48 |
|
| 49 |
static void |
| 50 |
new_discount() /* allocate space for direct contrib. record */ |
| 51 |
{ |
| 52 |
if (distsiz <= 0) |
| 53 |
return; |
| 54 |
direct_discount = (COLORV *)calloc(distsiz, sizeof(COLOR)); |
| 55 |
if (direct_discount == NULL) |
| 56 |
error(SYSTEM, "out of memory in new_discount"); |
| 57 |
} |
| 58 |
|
| 59 |
|
| 60 |
static void |
| 61 |
done_discount() /* clear off direct contrib. record */ |
| 62 |
{ |
| 63 |
if (direct_discount == NULL) |
| 64 |
return; |
| 65 |
free(direct_discount); |
| 66 |
direct_discount = NULL; |
| 67 |
} |
| 68 |
|
| 69 |
|
| 70 |
int |
| 71 |
process_ray( /* process a ray result or report error */ |
| 72 |
RAY *r, |
| 73 |
int rv |
| 74 |
) |
| 75 |
{ |
| 76 |
COLORV *colp; |
| 77 |
|
| 78 |
if (rv == 0) /* no result ready */ |
| 79 |
return(0); |
| 80 |
if (rv < 0) |
| 81 |
error(USER, "ray tracing process died"); |
| 82 |
if (r->rno >= distsiz) |
| 83 |
error(INTERNAL, "bad returned index in process_ray"); |
| 84 |
multcolor(r->rcol, r->rcoef); /* in case it's a source ray */ |
| 85 |
colp = &distarr[r->rno * 3]; |
| 86 |
addcolor(colp, r->rcol); |
| 87 |
if (r->rsrc >= 0 && /* remember source contrib. */ |
| 88 |
direct_discount != NULL) { |
| 89 |
colp = &direct_discount[r->rno * 3]; |
| 90 |
addcolor(colp, r->rcol); |
| 91 |
} |
| 92 |
return(1); |
| 93 |
} |
| 94 |
|
| 95 |
|
| 96 |
void |
| 97 |
raysamp( /* queue a ray sample */ |
| 98 |
int ndx, |
| 99 |
FVECT org, |
| 100 |
FVECT dir |
| 101 |
) |
| 102 |
{ |
| 103 |
RAY myRay; |
| 104 |
int rv; |
| 105 |
|
| 106 |
if ((ndx < 0) | (ndx >= distsiz)) |
| 107 |
error(INTERNAL, "bad index in raysamp"); |
| 108 |
VCOPY(myRay.rorg, org); |
| 109 |
VCOPY(myRay.rdir, dir); |
| 110 |
myRay.rmax = .0; |
| 111 |
rayorigin(&myRay, PRIMARY|SPECULAR, NULL, NULL); |
| 112 |
myRay.rno = ndx; |
| 113 |
/* queue ray, check result */ |
| 114 |
process_ray(&myRay, ray_pqueue(&myRay)); |
| 115 |
} |
| 116 |
|
| 117 |
|
| 118 |
void |
| 119 |
srcsamps( /* sample sources from this surface position */ |
| 120 |
struct illum_args *il, |
| 121 |
FVECT org, |
| 122 |
FVECT nrm, |
| 123 |
MAT4 ixfm |
| 124 |
) |
| 125 |
{ |
| 126 |
int nalt=1, nazi=1; |
| 127 |
SRCINDEX si; |
| 128 |
RAY sr; |
| 129 |
FVECT v; |
| 130 |
double d; |
| 131 |
int i, j; |
| 132 |
/* get sampling density */ |
| 133 |
if (il->sd == NULL && il->sampdens > 0) { |
| 134 |
i = PI * il->sampdens; |
| 135 |
nalt = sqrt(i/PI) + .5; |
| 136 |
nazi = PI*nalt + .5; |
| 137 |
} |
| 138 |
initsrcindex(&si); /* loop over (sub)sources */ |
| 139 |
for ( ; ; ) { |
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VCOPY(sr.rorg, org); /* pick side to shoot from */ |
| 141 |
if (il->sd != NULL) { |
| 142 |
int sn = si.sn; |
| 143 |
if (si.sp+1 >= si.np) ++sn; |
| 144 |
if (sn >= nsources) break; |
| 145 |
if (source[sn].sflags & SDISTANT) |
| 146 |
d = DOT(source[sn].sloc, nrm); |
| 147 |
else { |
| 148 |
VSUB(v, source[sn].sloc, org); |
| 149 |
d = DOT(v, nrm); |
| 150 |
} |
| 151 |
} else |
| 152 |
d = 1.0; /* only transmission */ |
| 153 |
if (d < 0.0) |
| 154 |
d = -1.0001*il->thick - 5.*FTINY; |
| 155 |
else |
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d = 5.*FTINY; |
| 157 |
VSUM(sr.rorg, sr.rorg, nrm, d); |
| 158 |
samplendx++; /* increment sample counter */ |
| 159 |
if (!srcray(&sr, NULL, &si)) |
| 160 |
break; /* end of sources */ |
| 161 |
/* index direction */ |
| 162 |
if (ixfm != NULL) |
| 163 |
multv3(v, sr.rdir, ixfm); |
| 164 |
else |
| 165 |
VCOPY(v, sr.rdir); |
| 166 |
if (il->sd != NULL) { |
| 167 |
i = getBSDF_incndx(il->sd, v); |
| 168 |
if (i < 0) |
| 169 |
continue; /* must not be important */ |
| 170 |
sr.rno = i; |
| 171 |
d = 1.0/getBSDF_incohm(il->sd, i); |
| 172 |
} else { |
| 173 |
if (v[2] >= -FTINY) |
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continue; /* only sample transmission */ |
| 175 |
v[0] = -v[0]; v[1] = -v[1]; v[2] = -v[2]; |
| 176 |
sr.rno = flatindex(v, nalt, nazi); |
| 177 |
d = nalt*nazi*(1./PI) * v[2]; |
| 178 |
} |
| 179 |
d *= si.dom; /* solid angle correction */ |
| 180 |
scalecolor(sr.rcoef, d); |
| 181 |
process_ray(&sr, ray_pqueue(&sr)); |
| 182 |
} |
| 183 |
} |
| 184 |
|
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|
| 186 |
void |
| 187 |
rayclean() /* finish all pending rays */ |
| 188 |
{ |
| 189 |
RAY myRay; |
| 190 |
|
| 191 |
while (process_ray(&myRay, ray_presult(&myRay, 0))) |
| 192 |
; |
| 193 |
} |
| 194 |
|
| 195 |
|
| 196 |
static void |
| 197 |
mkaxes( /* compute u and v to go with n */ |
| 198 |
FVECT u, |
| 199 |
FVECT v, |
| 200 |
FVECT n |
| 201 |
) |
| 202 |
{ |
| 203 |
register int i; |
| 204 |
|
| 205 |
v[0] = v[1] = v[2] = 0.0; |
| 206 |
for (i = 0; i < 3; i++) |
| 207 |
if (n[i] < 0.6 && n[i] > -0.6) |
| 208 |
break; |
| 209 |
v[i] = 1.0; |
| 210 |
fcross(u, v, n); |
| 211 |
normalize(u); |
| 212 |
fcross(v, n, u); |
| 213 |
} |
| 214 |
|
| 215 |
|
| 216 |
static void |
| 217 |
rounddir( /* compute uniform spherical direction */ |
| 218 |
register FVECT dv, |
| 219 |
double alt, |
| 220 |
double azi |
| 221 |
) |
| 222 |
{ |
| 223 |
double d1, d2; |
| 224 |
|
| 225 |
dv[2] = 1. - 2.*alt; |
| 226 |
d1 = sqrt(1. - dv[2]*dv[2]); |
| 227 |
d2 = 2.*PI * azi; |
| 228 |
dv[0] = d1*cos(d2); |
| 229 |
dv[1] = d1*sin(d2); |
| 230 |
} |
| 231 |
|
| 232 |
|
| 233 |
void |
| 234 |
flatdir( /* compute uniform hemispherical direction */ |
| 235 |
FVECT dv, |
| 236 |
double alt, |
| 237 |
double azi |
| 238 |
) |
| 239 |
{ |
| 240 |
double d1, d2; |
| 241 |
|
| 242 |
d1 = sqrt(alt); |
| 243 |
d2 = 2.*PI * azi; |
| 244 |
dv[0] = d1*cos(d2); |
| 245 |
dv[1] = d1*sin(d2); |
| 246 |
dv[2] = sqrt(1. - alt); |
| 247 |
} |
| 248 |
|
| 249 |
|
| 250 |
int |
| 251 |
flatindex( /* compute index for hemispherical direction */ |
| 252 |
FVECT dv, |
| 253 |
int nalt, |
| 254 |
int nazi |
| 255 |
) |
| 256 |
{ |
| 257 |
double d; |
| 258 |
int i, j; |
| 259 |
|
| 260 |
d = 1.0 - dv[2]*dv[2]; |
| 261 |
i = d*nalt; |
| 262 |
d = atan2(dv[1], dv[0]) * (0.5/PI); |
| 263 |
if (d < 0.0) d += 1.0; |
| 264 |
j = d*nazi + 0.5; |
| 265 |
if (j >= nazi) j = 0; |
| 266 |
return(i*nazi + j); |
| 267 |
} |
| 268 |
|
| 269 |
|
| 270 |
int |
| 271 |
printgeom( /* print out detailed geometry for BSDF */ |
| 272 |
struct BSDF_data *sd, |
| 273 |
char *xfrot, |
| 274 |
FVECT ctr, |
| 275 |
double s1, |
| 276 |
double s2 |
| 277 |
) |
| 278 |
{ |
| 279 |
static char mgftemp[] = TEMPLATE; |
| 280 |
char cmdbuf[64]; |
| 281 |
FILE *fp; |
| 282 |
double sca; |
| 283 |
|
| 284 |
if (sd == NULL || sd->mgf == NULL) |
| 285 |
return(0); |
| 286 |
if (sd->dim[0] <= FTINY || sd->dim[1] <= FTINY) |
| 287 |
return(0); |
| 288 |
if ((s1 > s2) ^ (sd->dim[0] > sd->dim[1])) { |
| 289 |
sca = s1; s1 = s2; s2 = sca; |
| 290 |
} |
| 291 |
s1 /= sd->dim[0]; |
| 292 |
s2 /= sd->dim[1]; |
| 293 |
sca = s1 > s2 ? s1 : s2; |
| 294 |
strcpy(mgftemp, TEMPLATE); |
| 295 |
if ((fp = fopen(mktemp(mgftemp), "w")) == NULL) |
| 296 |
error(SYSTEM, "cannot create temporary file for MGF"); |
| 297 |
/* prepend our transform */ |
| 298 |
fprintf(fp, "xf%s -s %.5f -t %.5g %.5g %.5g\n", |
| 299 |
xfrot, sca, ctr[0], ctr[1], ctr[2]); |
| 300 |
/* output given MGF description */ |
| 301 |
fputs(sd->mgf, fp); |
| 302 |
fputs("\nxf\n", fp); |
| 303 |
if (fclose(fp) == EOF) |
| 304 |
error(SYSTEM, "error writing MGF temporary file"); |
| 305 |
/* execute mgf2rad to convert MGF */ |
| 306 |
strcpy(cmdbuf, "mgf2rad "); |
| 307 |
strcpy(cmdbuf+8, mgftemp); |
| 308 |
fflush(stdout); |
| 309 |
system(cmdbuf); |
| 310 |
unlink(mgftemp); /* clean up */ |
| 311 |
return(1); |
| 312 |
} |
| 313 |
|
| 314 |
|
| 315 |
int |
| 316 |
my_default( /* default illum action */ |
| 317 |
OBJREC *ob, |
| 318 |
struct illum_args *il, |
| 319 |
char *nm |
| 320 |
) |
| 321 |
{ |
| 322 |
sprintf(errmsg, "(%s): cannot make illum for %s \"%s\"", |
| 323 |
nm, ofun[ob->otype].funame, ob->oname); |
| 324 |
error(WARNING, errmsg); |
| 325 |
printobj(il->altmat, ob); |
| 326 |
return(1); |
| 327 |
} |
| 328 |
|
| 329 |
|
| 330 |
int |
| 331 |
my_face( /* make an illum face */ |
| 332 |
OBJREC *ob, |
| 333 |
struct illum_args *il, |
| 334 |
char *nm |
| 335 |
) |
| 336 |
{ |
| 337 |
int dim[2]; |
| 338 |
int n, nalt, nazi, alti; |
| 339 |
double sp[2], r1, r2; |
| 340 |
int h; |
| 341 |
FVECT dn, org, dir; |
| 342 |
FVECT u, v; |
| 343 |
double ur[2], vr[2]; |
| 344 |
MAT4 xfm; |
| 345 |
char xfrot[64]; |
| 346 |
int nallow; |
| 347 |
FACE *fa; |
| 348 |
int i, j; |
| 349 |
/* get/check arguments */ |
| 350 |
fa = getface(ob); |
| 351 |
if (fa->area == 0.0) { |
| 352 |
freeface(ob); |
| 353 |
return(my_default(ob, il, nm)); |
| 354 |
} |
| 355 |
/* set up sampling */ |
| 356 |
if (il->sd != NULL) { |
| 357 |
if (!getBSDF_xfm(xfm, fa->norm, il->udir, xfrot)) { |
| 358 |
objerror(ob, WARNING, "illegal up direction"); |
| 359 |
freeface(ob); |
| 360 |
return(my_default(ob, il, nm)); |
| 361 |
} |
| 362 |
n = il->sd->ninc; |
| 363 |
} else { |
| 364 |
if (il->sampdens <= 0) { |
| 365 |
nalt = nazi = 1; /* diffuse assumption */ |
| 366 |
} else { |
| 367 |
n = PI * il->sampdens; |
| 368 |
nalt = sqrt(n/PI) + .5; |
| 369 |
nazi = PI*nalt + .5; |
| 370 |
} |
| 371 |
n = nazi*nalt; |
| 372 |
} |
| 373 |
newdist(n); |
| 374 |
/* take first edge >= sqrt(area) */ |
| 375 |
for (j = fa->nv-1, i = 0; i < fa->nv; j = i++) { |
| 376 |
u[0] = VERTEX(fa,i)[0] - VERTEX(fa,j)[0]; |
| 377 |
u[1] = VERTEX(fa,i)[1] - VERTEX(fa,j)[1]; |
| 378 |
u[2] = VERTEX(fa,i)[2] - VERTEX(fa,j)[2]; |
| 379 |
if ((r1 = DOT(u,u)) >= fa->area-FTINY) |
| 380 |
break; |
| 381 |
} |
| 382 |
if (i < fa->nv) { /* got one! -- let's align our axes */ |
| 383 |
r2 = 1.0/sqrt(r1); |
| 384 |
u[0] *= r2; u[1] *= r2; u[2] *= r2; |
| 385 |
fcross(v, fa->norm, u); |
| 386 |
} else /* oh well, we'll just have to wing it */ |
| 387 |
mkaxes(u, v, fa->norm); |
| 388 |
/* now, find limits in (u,v) coordinates */ |
| 389 |
ur[0] = vr[0] = FHUGE; |
| 390 |
ur[1] = vr[1] = -FHUGE; |
| 391 |
for (i = 0; i < fa->nv; i++) { |
| 392 |
r1 = DOT(VERTEX(fa,i),u); |
| 393 |
if (r1 < ur[0]) ur[0] = r1; |
| 394 |
if (r1 > ur[1]) ur[1] = r1; |
| 395 |
r2 = DOT(VERTEX(fa,i),v); |
| 396 |
if (r2 < vr[0]) vr[0] = r2; |
| 397 |
if (r2 > vr[1]) vr[1] = r2; |
| 398 |
} |
| 399 |
/* output detailed geometry? */ |
| 400 |
if (!(il->flags & IL_LIGHT) && il->sd != NULL && il->sd->mgf != NULL && |
| 401 |
il->thick <= FTINY) { |
| 402 |
for (j = 3; j--; ) |
| 403 |
org[j] = .5*(ur[0]+ur[1])*u[j] + |
| 404 |
.5*(vr[0]+vr[1])*v[j] + |
| 405 |
fa->offset*fa->norm[j]; |
| 406 |
printgeom(il->sd, xfrot, org, ur[1]-ur[0], vr[1]-vr[0]); |
| 407 |
} |
| 408 |
dim[0] = random(); |
| 409 |
/* sample polygon */ |
| 410 |
nallow = 5*n*il->nsamps; |
| 411 |
for (dim[1] = 0; dim[1] < n; dim[1]++) |
| 412 |
for (i = 0; i < il->nsamps; i++) { |
| 413 |
/* randomize direction */ |
| 414 |
h = ilhash(dim, 2) + i; |
| 415 |
if (il->sd != NULL) { |
| 416 |
r_BSDF_incvec(dir, il->sd, dim[1], urand(h), xfm); |
| 417 |
} else { |
| 418 |
multisamp(sp, 2, urand(h)); |
| 419 |
alti = dim[1]/nazi; |
| 420 |
r1 = (alti + sp[0])/nalt; |
| 421 |
r2 = (dim[1] - alti*nazi + sp[1] - .5)/nazi; |
| 422 |
flatdir(dn, r1, r2); |
| 423 |
for (j = 0; j < 3; j++) |
| 424 |
dir[j] = -dn[0]*u[j] - dn[1]*v[j] - |
| 425 |
dn[2]*fa->norm[j]; |
| 426 |
} |
| 427 |
/* randomize location */ |
| 428 |
do { |
| 429 |
multisamp(sp, 2, urand(h+4862+nallow)); |
| 430 |
r1 = ur[0] + (ur[1]-ur[0]) * sp[0]; |
| 431 |
r2 = vr[0] + (vr[1]-vr[0]) * sp[1]; |
| 432 |
for (j = 0; j < 3; j++) |
| 433 |
org[j] = r1*u[j] + r2*v[j] |
| 434 |
+ fa->offset*fa->norm[j]; |
| 435 |
} while (!inface(org, fa) && nallow-- > 0); |
| 436 |
if (nallow < 0) { |
| 437 |
objerror(ob, WARNING, "bad aspect"); |
| 438 |
rayclean(); |
| 439 |
freeface(ob); |
| 440 |
return(my_default(ob, il, nm)); |
| 441 |
} |
| 442 |
if (il->sd != NULL && DOT(dir, fa->norm) < -FTINY) |
| 443 |
r1 = -1.0001*il->thick - 5.*FTINY; |
| 444 |
else |
| 445 |
r1 = 5.*FTINY; |
| 446 |
for (j = 0; j < 3; j++) |
| 447 |
org[j] += r1*fa->norm[j]; |
| 448 |
/* send sample */ |
| 449 |
raysamp(dim[1], org, dir); |
| 450 |
} |
| 451 |
/* add in direct component? */ |
| 452 |
if (il->flags & IL_LIGHT || il->sd != NULL) { |
| 453 |
MAT4 ixfm; |
| 454 |
if (il->sd == NULL) { |
| 455 |
for (i = 3; i--; ) { |
| 456 |
ixfm[i][0] = u[i]; |
| 457 |
ixfm[i][1] = v[i]; |
| 458 |
ixfm[i][2] = fa->norm[i]; |
| 459 |
ixfm[i][3] = 0.; |
| 460 |
} |
| 461 |
ixfm[3][0] = ixfm[3][1] = ixfm[3][2] = 0.; |
| 462 |
ixfm[3][3] = 1.; |
| 463 |
} else { |
| 464 |
if (!invmat4(ixfm, xfm)) |
| 465 |
objerror(ob, INTERNAL, |
| 466 |
"cannot invert BSDF transform"); |
| 467 |
if (!(il->flags & IL_LIGHT)) |
| 468 |
new_discount(); |
| 469 |
} |
| 470 |
dim[0] = random(); |
| 471 |
nallow = 10*il->nsamps; |
| 472 |
for (i = 0; i < il->nsamps; i++) { |
| 473 |
/* randomize location */ |
| 474 |
h = dim[0] + samplendx++; |
| 475 |
do { |
| 476 |
multisamp(sp, 2, urand(h+nallow)); |
| 477 |
r1 = ur[0] + (ur[1]-ur[0]) * sp[0]; |
| 478 |
r2 = vr[0] + (vr[1]-vr[0]) * sp[1]; |
| 479 |
for (j = 0; j < 3; j++) |
| 480 |
org[j] = r1*u[j] + r2*v[j] |
| 481 |
+ fa->offset*fa->norm[j]; |
| 482 |
} while (!inface(org, fa) && nallow-- > 0); |
| 483 |
if (nallow < 0) { |
| 484 |
objerror(ob, WARNING, "bad aspect"); |
| 485 |
rayclean(); |
| 486 |
freeface(ob); |
| 487 |
return(my_default(ob, il, nm)); |
| 488 |
} |
| 489 |
/* sample source rays */ |
| 490 |
srcsamps(il, org, fa->norm, ixfm); |
| 491 |
} |
| 492 |
} |
| 493 |
/* wait for all rays to finish */ |
| 494 |
rayclean(); |
| 495 |
if (il->sd != NULL) { /* run distribution through BSDF */ |
| 496 |
nalt = sqrt(il->sd->nout/PI) + .5; |
| 497 |
nazi = PI*nalt + .5; |
| 498 |
redistribute(il->sd, nalt, nazi, u, v, fa->norm, xfm); |
| 499 |
done_discount(); |
| 500 |
if (!il->sampdens) |
| 501 |
il->sampdens = nalt*nazi/PI + .999; |
| 502 |
} |
| 503 |
/* write out the face and its distribution */ |
| 504 |
if (average(il, distarr, n)) { |
| 505 |
if (il->sampdens > 0) |
| 506 |
flatout(il, distarr, nalt, nazi, u, v, fa->norm); |
| 507 |
illumout(il, ob); |
| 508 |
} else |
| 509 |
printobj(il->altmat, ob); |
| 510 |
/* clean up */ |
| 511 |
freeface(ob); |
| 512 |
return(0); |
| 513 |
} |
| 514 |
|
| 515 |
|
| 516 |
int |
| 517 |
my_sphere( /* make an illum sphere */ |
| 518 |
register OBJREC *ob, |
| 519 |
struct illum_args *il, |
| 520 |
char *nm |
| 521 |
) |
| 522 |
{ |
| 523 |
int dim[3]; |
| 524 |
int n, nalt, nazi; |
| 525 |
double sp[4], r1, r2, r3; |
| 526 |
FVECT org, dir; |
| 527 |
FVECT u, v; |
| 528 |
register int i, j; |
| 529 |
/* check arguments */ |
| 530 |
if (ob->oargs.nfargs != 4) |
| 531 |
objerror(ob, USER, "bad # of arguments"); |
| 532 |
/* set up sampling */ |
| 533 |
if (il->sampdens <= 0) |
| 534 |
nalt = nazi = 1; |
| 535 |
else { |
| 536 |
n = 4.*PI * il->sampdens; |
| 537 |
nalt = sqrt(2./PI*n) + .5; |
| 538 |
nazi = PI/2.*nalt + .5; |
| 539 |
} |
| 540 |
if (il->sd != NULL) |
| 541 |
objerror(ob, WARNING, "BSDF ignored"); |
| 542 |
n = nalt*nazi; |
| 543 |
newdist(n); |
| 544 |
dim[0] = random(); |
| 545 |
/* sample sphere */ |
| 546 |
for (dim[1] = 0; dim[1] < nalt; dim[1]++) |
| 547 |
for (dim[2] = 0; dim[2] < nazi; dim[2]++) |
| 548 |
for (i = 0; i < il->nsamps; i++) { |
| 549 |
/* next sample point */ |
| 550 |
multisamp(sp, 4, urand(ilhash(dim,3)+i)); |
| 551 |
/* random direction */ |
| 552 |
r1 = (dim[1] + sp[0])/nalt; |
| 553 |
r2 = (dim[2] + sp[1] - .5)/nazi; |
| 554 |
rounddir(dir, r1, r2); |
| 555 |
/* random location */ |
| 556 |
mkaxes(u, v, dir); /* yuck! */ |
| 557 |
r3 = sqrt(sp[2]); |
| 558 |
r2 = 2.*PI*sp[3]; |
| 559 |
r1 = r3*ob->oargs.farg[3]*cos(r2); |
| 560 |
r2 = r3*ob->oargs.farg[3]*sin(r2); |
| 561 |
r3 = ob->oargs.farg[3]*sqrt(1.01-r3*r3); |
| 562 |
for (j = 0; j < 3; j++) { |
| 563 |
org[j] = ob->oargs.farg[j] + r1*u[j] + r2*v[j] + |
| 564 |
r3*dir[j]; |
| 565 |
dir[j] = -dir[j]; |
| 566 |
} |
| 567 |
/* send sample */ |
| 568 |
raysamp(dim[1]*nazi+dim[2], org, dir); |
| 569 |
} |
| 570 |
/* wait for all rays to finish */ |
| 571 |
rayclean(); |
| 572 |
/* write out the sphere and its distribution */ |
| 573 |
if (average(il, distarr, n)) { |
| 574 |
if (il->sampdens > 0) |
| 575 |
roundout(il, distarr, nalt, nazi); |
| 576 |
else |
| 577 |
objerror(ob, WARNING, "diffuse distribution"); |
| 578 |
illumout(il, ob); |
| 579 |
} else |
| 580 |
printobj(il->altmat, ob); |
| 581 |
/* clean up */ |
| 582 |
return(1); |
| 583 |
} |
| 584 |
|
| 585 |
|
| 586 |
int |
| 587 |
my_ring( /* make an illum ring */ |
| 588 |
OBJREC *ob, |
| 589 |
struct illum_args *il, |
| 590 |
char *nm |
| 591 |
) |
| 592 |
{ |
| 593 |
int dim[2]; |
| 594 |
int n, nalt, nazi, alti; |
| 595 |
double sp[2], r1, r2, r3; |
| 596 |
int h; |
| 597 |
FVECT dn, org, dir; |
| 598 |
FVECT u, v; |
| 599 |
MAT4 xfm; |
| 600 |
CONE *co; |
| 601 |
int i, j; |
| 602 |
/* get/check arguments */ |
| 603 |
co = getcone(ob, 0); |
| 604 |
/* set up sampling */ |
| 605 |
if (il->sd != NULL) { |
| 606 |
if (!getBSDF_xfm(xfm, co->ad, il->udir, NULL)) { |
| 607 |
objerror(ob, WARNING, "illegal up direction"); |
| 608 |
freecone(ob); |
| 609 |
return(my_default(ob, il, nm)); |
| 610 |
} |
| 611 |
n = il->sd->ninc; |
| 612 |
} else { |
| 613 |
if (il->sampdens <= 0) { |
| 614 |
nalt = nazi = 1; /* diffuse assumption */ |
| 615 |
} else { |
| 616 |
n = PI * il->sampdens; |
| 617 |
nalt = sqrt(n/PI) + .5; |
| 618 |
nazi = PI*nalt + .5; |
| 619 |
} |
| 620 |
n = nazi*nalt; |
| 621 |
} |
| 622 |
newdist(n); |
| 623 |
mkaxes(u, v, co->ad); |
| 624 |
dim[0] = random(); |
| 625 |
/* sample disk */ |
| 626 |
for (dim[1] = 0; dim[1] < n; dim[1]++) |
| 627 |
for (i = 0; i < il->nsamps; i++) { |
| 628 |
/* next sample point */ |
| 629 |
h = ilhash(dim,2) + i; |
| 630 |
/* randomize direction */ |
| 631 |
if (il->sd != NULL) { |
| 632 |
r_BSDF_incvec(dir, il->sd, dim[1], urand(h), xfm); |
| 633 |
} else { |
| 634 |
multisamp(sp, 2, urand(h)); |
| 635 |
alti = dim[1]/nazi; |
| 636 |
r1 = (alti + sp[0])/nalt; |
| 637 |
r2 = (dim[1] - alti*nazi + sp[1] - .5)/nazi; |
| 638 |
flatdir(dn, r1, r2); |
| 639 |
for (j = 0; j < 3; j++) |
| 640 |
dir[j] = -dn[0]*u[j] - dn[1]*v[j] - dn[2]*co->ad[j]; |
| 641 |
} |
| 642 |
/* randomize location */ |
| 643 |
multisamp(sp, 2, urand(h+8371)); |
| 644 |
r3 = sqrt(CO_R0(co)*CO_R0(co) + |
| 645 |
sp[0]*(CO_R1(co)*CO_R1(co) - CO_R0(co)*CO_R0(co))); |
| 646 |
r2 = 2.*PI*sp[1]; |
| 647 |
r1 = r3*cos(r2); |
| 648 |
r2 = r3*sin(r2); |
| 649 |
if (il->sd != NULL && DOT(dir, co->ad) < -FTINY) |
| 650 |
r3 = -1.0001*il->thick - 5.*FTINY; |
| 651 |
else |
| 652 |
r3 = 5.*FTINY; |
| 653 |
for (j = 0; j < 3; j++) |
| 654 |
org[j] = CO_P0(co)[j] + r1*u[j] + r2*v[j] + |
| 655 |
r3*co->ad[j]; |
| 656 |
/* send sample */ |
| 657 |
raysamp(dim[1], org, dir); |
| 658 |
} |
| 659 |
/* add in direct component? */ |
| 660 |
if (il->flags & IL_LIGHT || il->sd != NULL) { |
| 661 |
MAT4 ixfm; |
| 662 |
if (il->sd == NULL) { |
| 663 |
for (i = 3; i--; ) { |
| 664 |
ixfm[i][0] = u[i]; |
| 665 |
ixfm[i][1] = v[i]; |
| 666 |
ixfm[i][2] = co->ad[i]; |
| 667 |
ixfm[i][3] = 0.; |
| 668 |
} |
| 669 |
ixfm[3][0] = ixfm[3][1] = ixfm[3][2] = 0.; |
| 670 |
ixfm[3][3] = 1.; |
| 671 |
} else { |
| 672 |
if (!invmat4(ixfm, xfm)) |
| 673 |
objerror(ob, INTERNAL, |
| 674 |
"cannot invert BSDF transform"); |
| 675 |
if (!(il->flags & IL_LIGHT)) |
| 676 |
new_discount(); |
| 677 |
} |
| 678 |
dim[0] = random(); |
| 679 |
for (i = 0; i < il->nsamps; i++) { |
| 680 |
/* randomize location */ |
| 681 |
h = dim[0] + samplendx++; |
| 682 |
multisamp(sp, 2, urand(h)); |
| 683 |
r3 = sqrt(CO_R0(co)*CO_R0(co) + |
| 684 |
sp[0]*(CO_R1(co)*CO_R1(co) - CO_R0(co)*CO_R0(co))); |
| 685 |
r2 = 2.*PI*sp[1]; |
| 686 |
r1 = r3*cos(r2); |
| 687 |
r2 = r3*sin(r2); |
| 688 |
for (j = 0; j < 3; j++) |
| 689 |
org[j] = CO_P0(co)[j] + r1*u[j] + r2*v[j]; |
| 690 |
/* sample source rays */ |
| 691 |
srcsamps(il, org, co->ad, ixfm); |
| 692 |
} |
| 693 |
} |
| 694 |
/* wait for all rays to finish */ |
| 695 |
rayclean(); |
| 696 |
if (il->sd != NULL) { /* run distribution through BSDF */ |
| 697 |
nalt = sqrt(il->sd->nout/PI) + .5; |
| 698 |
nazi = PI*nalt + .5; |
| 699 |
redistribute(il->sd, nalt, nazi, u, v, co->ad, xfm); |
| 700 |
done_discount(); |
| 701 |
if (!il->sampdens) |
| 702 |
il->sampdens = nalt*nazi/PI + .999; |
| 703 |
} |
| 704 |
/* write out the ring and its distribution */ |
| 705 |
if (average(il, distarr, n)) { |
| 706 |
if (il->sampdens > 0) |
| 707 |
flatout(il, distarr, nalt, nazi, u, v, co->ad); |
| 708 |
illumout(il, ob); |
| 709 |
} else |
| 710 |
printobj(il->altmat, ob); |
| 711 |
/* clean up */ |
| 712 |
freecone(ob); |
| 713 |
return(1); |
| 714 |
} |
| 715 |
|
| 716 |
|
| 717 |
void |
| 718 |
redistribute( /* pass distarr ray sums through BSDF */ |
| 719 |
struct BSDF_data *b, |
| 720 |
int nalt, |
| 721 |
int nazi, |
| 722 |
FVECT u, |
| 723 |
FVECT v, |
| 724 |
FVECT w, |
| 725 |
MAT4 xm |
| 726 |
) |
| 727 |
{ |
| 728 |
int nout = 0; |
| 729 |
MAT4 mymat, inmat; |
| 730 |
COLORV *idist; |
| 731 |
COLORV *cp; |
| 732 |
FVECT dv; |
| 733 |
double wt; |
| 734 |
int i, j, k, c, o; |
| 735 |
COLOR col, cinc; |
| 736 |
/* copy incoming distribution */ |
| 737 |
if (b->ninc > distsiz) |
| 738 |
error(INTERNAL, "error 1 in redistribute"); |
| 739 |
idist = (COLORV *)malloc(sizeof(COLOR)*b->ninc); |
| 740 |
if (idist == NULL) |
| 741 |
error(SYSTEM, "out of memory in redistribute"); |
| 742 |
memcpy(idist, distarr, sizeof(COLOR)*b->ninc); |
| 743 |
/* compose direction transform */ |
| 744 |
for (i = 3; i--; ) { |
| 745 |
mymat[i][0] = u[i]; |
| 746 |
mymat[i][1] = v[i]; |
| 747 |
mymat[i][2] = w[i]; |
| 748 |
mymat[i][3] = 0.; |
| 749 |
} |
| 750 |
mymat[3][0] = mymat[3][1] = mymat[3][2] = 0.; |
| 751 |
mymat[3][3] = 1.; |
| 752 |
if (xm != NULL) |
| 753 |
multmat4(mymat, xm, mymat); |
| 754 |
for (i = 3; i--; ) { /* make sure it's normalized */ |
| 755 |
wt = 1./sqrt( mymat[0][i]*mymat[0][i] + |
| 756 |
mymat[1][i]*mymat[1][i] + |
| 757 |
mymat[2][i]*mymat[2][i] ); |
| 758 |
for (j = 3; j--; ) |
| 759 |
mymat[j][i] *= wt; |
| 760 |
} |
| 761 |
if (!invmat4(inmat, mymat)) /* need inverse as well */ |
| 762 |
error(INTERNAL, "cannot invert BSDF transform"); |
| 763 |
newdist(nalt*nazi); /* resample distribution */ |
| 764 |
for (i = b->ninc; i--; ) { |
| 765 |
int direct_out = -1; |
| 766 |
COLOR cdir; |
| 767 |
getBSDF_incvec(dv, b, i); /* compute incident irrad. */ |
| 768 |
multv3(dv, dv, mymat); |
| 769 |
if (dv[2] < 0.0) { |
| 770 |
dv[0] = -dv[0]; dv[1] = -dv[1]; dv[2] = -dv[2]; |
| 771 |
direct_out += (direct_discount != NULL); |
| 772 |
} |
| 773 |
wt = getBSDF_incohm(b, i); |
| 774 |
wt *= dv[2]; /* solid_angle*cosine(theta) */ |
| 775 |
cp = &idist[3*i]; |
| 776 |
copycolor(cinc, cp); |
| 777 |
scalecolor(cinc, wt); |
| 778 |
if (!direct_out) { /* discount direct contr. */ |
| 779 |
cp = &direct_discount[3*i]; |
| 780 |
copycolor(cdir, cp); |
| 781 |
scalecolor(cdir, -wt); |
| 782 |
if (b->nout != b->ninc) |
| 783 |
direct_out = flatindex(dv, nalt, nazi); |
| 784 |
else |
| 785 |
direct_out = i; /* assumes dist. mirroring */ |
| 786 |
} |
| 787 |
for (k = nalt; k--; ) /* loop over distribution */ |
| 788 |
for (j = nazi; j--; ) { |
| 789 |
int rstart = random(); |
| 790 |
for (c = NBSDFSAMPS; c--; ) { |
| 791 |
double sp[2]; |
| 792 |
multisamp(sp, 2, urand(rstart+c)); |
| 793 |
flatdir(dv, (k + sp[0])/nalt, |
| 794 |
(j + .5 - sp[1])/nazi); |
| 795 |
multv3(dv, dv, inmat); |
| 796 |
/* evaluate BSDF @ outgoing */ |
| 797 |
o = getBSDF_outndx(b, dv); |
| 798 |
if (o < 0) { |
| 799 |
nout++; |
| 800 |
continue; |
| 801 |
} |
| 802 |
wt = BSDF_value(b, i, o) * (1./NBSDFSAMPS); |
| 803 |
copycolor(col, cinc); |
| 804 |
if (b->nout != b->ninc) |
| 805 |
o = k*nazi + j; |
| 806 |
if (o == direct_out) |
| 807 |
addcolor(col, cdir); /* minus direct */ |
| 808 |
scalecolor(col, wt); |
| 809 |
cp = &distarr[3*(k*nazi + j)]; |
| 810 |
addcolor(cp, col); /* sum into distribution */ |
| 811 |
} |
| 812 |
} |
| 813 |
} |
| 814 |
free(idist); /* free temp space */ |
| 815 |
if (nout) { |
| 816 |
sprintf(errmsg, "missing %.1f%% of BSDF directions", |
| 817 |
100.*nout/(b->ninc*nalt*nazi*NBSDFSAMPS)); |
| 818 |
error(WARNING, errmsg); |
| 819 |
} |
| 820 |
} |
