101 |
|
if (ldot > FTINY && (np->specfl&(SP_REFL|SP_BADU)) == SP_REFL) { |
102 |
|
/* |
103 |
|
* Compute specular reflection coefficient using |
104 |
< |
* anisotropic gaussian distribution model. |
104 |
> |
* anisotropic Gaussian distribution model. |
105 |
|
*/ |
106 |
|
/* add source width if flat */ |
107 |
|
if (np->specfl & SP_FLAT) |
119 |
|
dtmp1 *= dtmp1 / au2; |
120 |
|
dtmp2 = DOT(np->v, h); |
121 |
|
dtmp2 *= dtmp2 / av2; |
122 |
< |
/* gaussian */ |
122 |
> |
/* new W-G-M-D model */ |
123 |
|
dtmp = DOT(np->pnorm, h); |
124 |
< |
dtmp = (dtmp1 + dtmp2) / (dtmp*dtmp); |
125 |
< |
dtmp = exp(-dtmp) / (4.0*PI * np->pdot * sqrt(au2*av2)); |
124 |
> |
dtmp *= dtmp; |
125 |
> |
dtmp1 = (dtmp1 + dtmp2) / dtmp; |
126 |
> |
dtmp = exp(-dtmp1) * DOT(h,h) / |
127 |
> |
(PI * dtmp*dtmp * sqrt(au2*av2)); |
128 |
|
/* worth using? */ |
129 |
|
if (dtmp > FTINY) { |
130 |
|
copycolor(ctmp, np->scolor); |
131 |
< |
dtmp *= omega; |
131 |
> |
dtmp *= ldot * omega; |
132 |
|
scalecolor(ctmp, dtmp); |
133 |
|
addcolor(cval, ctmp); |
134 |
|
} |
168 |
|
} |
169 |
|
} else |
170 |
|
dtmp = 0.0; |
171 |
< |
/* gaussian */ |
171 |
> |
/* Gaussian */ |
172 |
|
dtmp = exp(-dtmp) * (1.0/PI) * sqrt(-ldot/(np->pdot*au2*av2)); |
173 |
|
/* worth using? */ |
174 |
|
if (dtmp > FTINY) { |
236 |
|
if (specthresh >= nd.rspec-FTINY) |
237 |
|
nd.specfl |= SP_RBLT; |
238 |
|
/* compute refl. direction */ |
239 |
< |
for (i = 0; i < 3; i++) |
238 |
< |
nd.vrefl[i] = r->rdir[i] + 2.0*nd.pdot*nd.pnorm[i]; |
239 |
> |
VSUM(nd.vrefl, r->rdir, nd.pnorm, 2.0*nd.pdot); |
240 |
|
if (DOT(nd.vrefl, r->ron) <= FTINY) /* penetration? */ |
241 |
< |
for (i = 0; i < 3; i++) /* safety measure */ |
241 |
< |
nd.vrefl[i] = r->rdir[i] + 2.*r->rod*r->ron[i]; |
241 |
> |
VSUM(nd.vrefl, r->rdir, r->ron, 2.0*r->rod); |
242 |
|
} |
243 |
|
/* compute transmission */ |
244 |
|
if (m->otype == MAT_TRANS2) { |
339 |
|
|
340 |
|
|
341 |
|
static void |
342 |
< |
agaussamp( /* sample anisotropic gaussian specular */ |
342 |
> |
agaussamp( /* sample anisotropic Gaussian specular */ |
343 |
|
RAY *r, |
344 |
|
register ANISODAT *np |
345 |
|
) |
348 |
|
FVECT h; |
349 |
|
double rv[2]; |
350 |
|
double d, sinp, cosp; |
351 |
< |
int niter; |
351 |
> |
COLOR scol; |
352 |
> |
int maxiter, ntrials, nstarget, nstaken; |
353 |
|
register int i; |
354 |
|
/* compute reflection */ |
355 |
|
if ((np->specfl & (SP_REFL|SP_RBLT)) == SP_REFL && |
356 |
|
rayorigin(&sr, SPECULAR, r, np->scolor) == 0) { |
357 |
< |
dimlist[ndims++] = (int)np->mp; |
358 |
< |
for (niter = 0; niter < MAXITER; niter++) { |
359 |
< |
if (niter) |
357 |
> |
nstarget = 1; |
358 |
> |
if (specjitter > 1.5) { /* multiple samples? */ |
359 |
> |
nstarget = specjitter*r->rweight + .5; |
360 |
> |
if (sr.rweight <= minweight*nstarget) |
361 |
> |
nstarget = sr.rweight/minweight; |
362 |
> |
if (nstarget > 1) { |
363 |
> |
d = 1./nstarget; |
364 |
> |
scalecolor(sr.rcoef, d); |
365 |
> |
sr.rweight *= d; |
366 |
> |
} else |
367 |
> |
nstarget = 1; |
368 |
> |
} |
369 |
> |
setcolor(scol, 0., 0., 0.); |
370 |
> |
dimlist[ndims++] = (int)(size_t)np->mp; |
371 |
> |
maxiter = MAXITER*nstarget; |
372 |
> |
for (nstaken = ntrials = 0; nstaken < nstarget && |
373 |
> |
ntrials < maxiter; ntrials++) { |
374 |
> |
if (ntrials) |
375 |
|
d = frandom(); |
376 |
|
else |
377 |
|
d = urand(ilhash(dimlist,ndims)+samplendx); |
379 |
|
d = 2.0*PI * rv[0]; |
380 |
|
cosp = tcos(d) * np->u_alpha; |
381 |
|
sinp = tsin(d) * np->v_alpha; |
382 |
< |
d = sqrt(cosp*cosp + sinp*sinp); |
383 |
< |
cosp /= d; |
384 |
< |
sinp /= d; |
385 |
< |
rv[1] = 1.0 - specjitter*rv[1]; |
382 |
> |
d = 1./sqrt(cosp*cosp + sinp*sinp); |
383 |
> |
cosp *= d; |
384 |
> |
sinp *= d; |
385 |
> |
if ((0. <= specjitter) & (specjitter < 1.)) |
386 |
> |
rv[1] = 1.0 - specjitter*rv[1]; |
387 |
|
if (rv[1] <= FTINY) |
388 |
|
d = 1.0; |
389 |
|
else |
394 |
|
h[i] = np->pnorm[i] + |
395 |
|
d*(cosp*np->u[i] + sinp*np->v[i]); |
396 |
|
d = -2.0 * DOT(h, r->rdir) / (1.0 + d*d); |
397 |
< |
for (i = 0; i < 3; i++) |
398 |
< |
sr.rdir[i] = r->rdir[i] + d*h[i]; |
399 |
< |
if (DOT(sr.rdir, r->ron) > FTINY) { |
400 |
< |
checknorm(sr.rdir); |
397 |
> |
VSUM(sr.rdir, r->rdir, h, d); |
398 |
> |
/* sample rejection test */ |
399 |
> |
if ((d = DOT(sr.rdir, r->ron)) <= FTINY) |
400 |
> |
continue; |
401 |
> |
checknorm(sr.rdir); |
402 |
> |
if (nstarget > 1) { /* W-G-M-D adjustment */ |
403 |
> |
if (nstaken) rayclear(&sr); |
404 |
|
rayvalue(&sr); |
405 |
+ |
d = 2./(1. + r->rod/d); |
406 |
+ |
scalecolor(sr.rcol, d); |
407 |
+ |
addcolor(scol, sr.rcol); |
408 |
+ |
} else { |
409 |
+ |
rayvalue(&sr); |
410 |
|
multcolor(sr.rcol, sr.rcoef); |
411 |
|
addcolor(r->rcol, sr.rcol); |
387 |
– |
break; |
412 |
|
} |
413 |
+ |
++nstaken; |
414 |
|
} |
415 |
+ |
if (nstarget > 1) { /* final W-G-M-D weighting */ |
416 |
+ |
multcolor(scol, sr.rcoef); |
417 |
+ |
d = (double)nstarget/ntrials; |
418 |
+ |
scalecolor(scol, d); |
419 |
+ |
addcolor(r->rcol, scol); |
420 |
+ |
} |
421 |
|
ndims--; |
422 |
|
} |
423 |
|
/* compute transmission */ |
425 |
|
scalecolor(sr.rcoef, np->tspec); |
426 |
|
if ((np->specfl & (SP_TRAN|SP_TBLT)) == SP_TRAN && |
427 |
|
rayorigin(&sr, SPECULAR, r, sr.rcoef) == 0) { |
428 |
< |
dimlist[ndims++] = (int)np->mp; |
429 |
< |
for (niter = 0; niter < MAXITER; niter++) { |
430 |
< |
if (niter) |
428 |
> |
nstarget = 1; |
429 |
> |
if (specjitter > 1.5) { /* multiple samples? */ |
430 |
> |
nstarget = specjitter*r->rweight + .5; |
431 |
> |
if (sr.rweight <= minweight*nstarget) |
432 |
> |
nstarget = sr.rweight/minweight; |
433 |
> |
if (nstarget > 1) { |
434 |
> |
d = 1./nstarget; |
435 |
> |
scalecolor(sr.rcoef, d); |
436 |
> |
sr.rweight *= d; |
437 |
> |
} else |
438 |
> |
nstarget = 1; |
439 |
> |
} |
440 |
> |
dimlist[ndims++] = (int)(size_t)np->mp; |
441 |
> |
maxiter = MAXITER*nstarget; |
442 |
> |
for (nstaken = ntrials = 0; nstaken < nstarget && |
443 |
> |
ntrials < maxiter; ntrials++) { |
444 |
> |
if (ntrials) |
445 |
|
d = frandom(); |
446 |
|
else |
447 |
|
d = urand(ilhash(dimlist,ndims)+1823+samplendx); |
449 |
|
d = 2.0*PI * rv[0]; |
450 |
|
cosp = tcos(d) * np->u_alpha; |
451 |
|
sinp = tsin(d) * np->v_alpha; |
452 |
< |
d = sqrt(cosp*cosp + sinp*sinp); |
453 |
< |
cosp /= d; |
454 |
< |
sinp /= d; |
455 |
< |
rv[1] = 1.0 - specjitter*rv[1]; |
452 |
> |
d = 1./sqrt(cosp*cosp + sinp*sinp); |
453 |
> |
cosp *= d; |
454 |
> |
sinp *= d; |
455 |
> |
if ((0. <= specjitter) & (specjitter < 1.)) |
456 |
> |
rv[1] = 1.0 - specjitter*rv[1]; |
457 |
|
if (rv[1] <= FTINY) |
458 |
|
d = 1.0; |
459 |
|
else |
463 |
|
for (i = 0; i < 3; i++) |
464 |
|
sr.rdir[i] = np->prdir[i] + |
465 |
|
d*(cosp*np->u[i] + sinp*np->v[i]); |
466 |
< |
if (DOT(sr.rdir, r->ron) < -FTINY) { |
467 |
< |
normalize(sr.rdir); /* OK, normalize */ |
468 |
< |
rayvalue(&sr); |
469 |
< |
multcolor(sr.rcol, sr.rcoef); |
470 |
< |
addcolor(r->rcol, sr.rcol); |
471 |
< |
break; |
472 |
< |
} |
466 |
> |
if (DOT(sr.rdir, r->ron) >= -FTINY) |
467 |
> |
continue; |
468 |
> |
normalize(sr.rdir); /* OK, normalize */ |
469 |
> |
if (nstaken) /* multi-sampling */ |
470 |
> |
rayclear(&sr); |
471 |
> |
rayvalue(&sr); |
472 |
> |
multcolor(sr.rcol, sr.rcoef); |
473 |
> |
addcolor(r->rcol, sr.rcol); |
474 |
> |
++nstaken; |
475 |
|
} |
476 |
|
ndims--; |
477 |
|
} |