21 |
|
|
22 |
|
/* |
23 |
|
* This routine implements the anisotropic Gaussian |
24 |
< |
* model described by Ward in Siggraph `92 article. |
24 |
> |
* model described by Ward in Siggraph `92 article, updated with |
25 |
> |
* normalization and sampling adjustments due to Geisler-Moroder and Duer. |
26 |
|
* We orient the surface towards the incoming ray, so a single |
27 |
|
* surface can be used to represent an infinitely thin object. |
28 |
|
* |
29 |
|
* Arguments for MAT_PLASTIC2 and MAT_METAL2 are: |
30 |
|
* 4+ ux uy uz funcfile [transform...] |
31 |
|
* 0 |
32 |
< |
* 6 red grn blu specular-frac. u-facet-slope v-facet-slope |
32 |
> |
* 6 red grn blu specular-frac. u-rough v-rough |
33 |
|
* |
34 |
|
* Real arguments for MAT_TRANS2 are: |
35 |
|
* 8 red grn blu rspec u-rough v-rough trans tspec |
61 |
|
double pdot; /* perturbed dot product */ |
62 |
|
} ANISODAT; /* anisotropic material data */ |
63 |
|
|
63 |
– |
static srcdirf_t diraniso; |
64 |
|
static void getacoords(RAY *r, ANISODAT *np); |
65 |
|
static void agaussamp(RAY *r, ANISODAT *np); |
66 |
|
|
68 |
|
static void |
69 |
|
diraniso( /* compute source contribution */ |
70 |
|
COLOR cval, /* returned coefficient */ |
71 |
< |
void *nnp, /* material data */ |
71 |
> |
void *nnp, /* material data */ |
72 |
|
FVECT ldir, /* light source direction */ |
73 |
|
double omega /* light source size */ |
74 |
|
) |
75 |
|
{ |
76 |
< |
register ANISODAT *np = nnp; |
76 |
> |
ANISODAT *np = nnp; |
77 |
|
double ldot; |
78 |
|
double dtmp, dtmp1, dtmp2; |
79 |
|
FVECT h; |
87 |
|
if (ldot < 0.0 ? np->trans <= FTINY : np->trans >= 1.0-FTINY) |
88 |
|
return; /* wrong side */ |
89 |
|
|
90 |
< |
if (ldot > FTINY && np->rdiff > FTINY) { |
90 |
> |
if ((ldot > FTINY) & (np->rdiff > FTINY)) { |
91 |
|
/* |
92 |
|
* Compute and add diffuse reflected component to returned |
93 |
|
* color. The diffuse reflected component will always be |
111 |
|
au2 += np->u_alpha*np->u_alpha; |
112 |
|
av2 += np->v_alpha*np->v_alpha; |
113 |
|
/* half vector */ |
114 |
< |
h[0] = ldir[0] - np->rp->rdir[0]; |
115 |
< |
h[1] = ldir[1] - np->rp->rdir[1]; |
116 |
< |
h[2] = ldir[2] - np->rp->rdir[2]; |
114 |
> |
VSUB(h, ldir, np->rp->rdir); |
115 |
|
/* ellipse */ |
116 |
|
dtmp1 = DOT(np->u, h); |
117 |
|
dtmp1 *= dtmp1 / au2; |
131 |
|
addcolor(cval, ctmp); |
132 |
|
} |
133 |
|
} |
134 |
< |
if (ldot < -FTINY && np->tdiff > FTINY) { |
134 |
> |
if ((ldot < -FTINY) & (np->tdiff > FTINY)) { |
135 |
|
/* |
136 |
|
* Compute diffuse transmission. |
137 |
|
*/ |
150 |
|
au2 += np->u_alpha*np->u_alpha; |
151 |
|
av2 += np->v_alpha*np->v_alpha; |
152 |
|
/* "half vector" */ |
153 |
< |
h[0] = ldir[0] - np->prdir[0]; |
156 |
< |
h[1] = ldir[1] - np->prdir[1]; |
157 |
< |
h[2] = ldir[2] - np->prdir[2]; |
153 |
> |
VSUB(h, ldir, np->prdir); |
154 |
|
dtmp = DOT(h,h); |
155 |
|
if (dtmp > FTINY*FTINY) { |
156 |
|
dtmp1 = DOT(h,np->pnorm); |
177 |
|
} |
178 |
|
|
179 |
|
|
180 |
< |
extern int |
180 |
> |
int |
181 |
|
m_aniso( /* shade ray that hit something anisotropic */ |
182 |
< |
register OBJREC *m, |
183 |
< |
register RAY *r |
182 |
> |
OBJREC *m, |
183 |
> |
RAY *r |
184 |
|
) |
185 |
|
{ |
186 |
|
ANISODAT nd; |
187 |
|
COLOR ctmp; |
188 |
< |
register int i; |
188 |
> |
int i; |
189 |
|
/* easy shadow test */ |
190 |
|
if (r->crtype & SHADOW) |
191 |
|
return(1); |
212 |
|
nd.specfl = 0; |
213 |
|
nd.u_alpha = m->oargs.farg[4]; |
214 |
|
nd.v_alpha = m->oargs.farg[5]; |
215 |
< |
if (nd.u_alpha <= FTINY || nd.v_alpha <= FTINY) |
215 |
> |
if ((nd.u_alpha <= FTINY) | (nd.v_alpha <= FTINY)) |
216 |
|
objerror(m, USER, "roughness too small"); |
217 |
|
|
218 |
|
nd.pdot = raynormal(nd.pnorm, r); /* perturb normal */ |
273 |
|
|
274 |
|
if (nd.rdiff > FTINY) { /* ambient from this side */ |
275 |
|
copycolor(ctmp, nd.mcolor); /* modified by material color */ |
276 |
< |
if (nd.specfl & SP_RBLT) |
277 |
< |
scalecolor(ctmp, 1.0-nd.trans); |
278 |
< |
else |
283 |
< |
scalecolor(ctmp, nd.rdiff); |
276 |
> |
scalecolor(ctmp, nd.rdiff); |
277 |
> |
if (nd.specfl & SP_RBLT) /* add in specular as well? */ |
278 |
> |
addcolor(ctmp, nd.scolor); |
279 |
|
multambient(ctmp, r, nd.pnorm); |
280 |
|
addcolor(r->rcol, ctmp); /* add to returned color */ |
281 |
|
} |
305 |
|
static void |
306 |
|
getacoords( /* set up coordinate system */ |
307 |
|
RAY *r, |
308 |
< |
register ANISODAT *np |
308 |
> |
ANISODAT *np |
309 |
|
) |
310 |
|
{ |
311 |
< |
register MFUNC *mf; |
312 |
< |
register int i; |
311 |
> |
MFUNC *mf; |
312 |
> |
int i; |
313 |
|
|
314 |
|
mf = getfunc(np->mp, 3, 0x7, 1); |
315 |
|
setfunc(np->mp, r); |
316 |
|
errno = 0; |
317 |
|
for (i = 0; i < 3; i++) |
318 |
|
np->u[i] = evalue(mf->ep[i]); |
319 |
< |
if (errno == EDOM || errno == ERANGE) { |
319 |
> |
if ((errno == EDOM) | (errno == ERANGE)) { |
320 |
|
objerror(np->mp, WARNING, "compute error"); |
321 |
|
np->specfl |= SP_BADU; |
322 |
|
return; |
323 |
|
} |
324 |
< |
if (mf->f != &unitxf) |
325 |
< |
multv3(np->u, np->u, mf->f->xfm); |
324 |
> |
if (mf->fxp != &unitxf) |
325 |
> |
multv3(np->u, np->u, mf->fxp->xfm); |
326 |
|
fcross(np->v, np->pnorm, np->u); |
327 |
|
if (normalize(np->v) == 0.0) { |
328 |
|
objerror(np->mp, WARNING, "illegal orientation vector"); |
336 |
|
static void |
337 |
|
agaussamp( /* sample anisotropic Gaussian specular */ |
338 |
|
RAY *r, |
339 |
< |
register ANISODAT *np |
339 |
> |
ANISODAT *np |
340 |
|
) |
341 |
|
{ |
342 |
|
RAY sr; |
344 |
|
double rv[2]; |
345 |
|
double d, sinp, cosp; |
346 |
|
COLOR scol; |
347 |
< |
int niter, ns2go; |
348 |
< |
register int i; |
347 |
> |
int maxiter, ntrials, nstarget, nstaken; |
348 |
> |
int i; |
349 |
|
/* compute reflection */ |
350 |
|
if ((np->specfl & (SP_REFL|SP_RBLT)) == SP_REFL && |
351 |
|
rayorigin(&sr, SPECULAR, r, np->scolor) == 0) { |
352 |
< |
copycolor(scol, np->scolor); |
358 |
< |
ns2go = 1; |
352 |
> |
nstarget = 1; |
353 |
|
if (specjitter > 1.5) { /* multiple samples? */ |
354 |
< |
ns2go = specjitter*r->rweight + .5; |
355 |
< |
if (sr.rweight <= minweight*ns2go) |
356 |
< |
ns2go = sr.rweight/minweight; |
357 |
< |
if (ns2go > 1) { |
358 |
< |
d = 1./ns2go; |
359 |
< |
scalecolor(scol, d); |
354 |
> |
nstarget = specjitter*r->rweight + .5; |
355 |
> |
if (sr.rweight <= minweight*nstarget) |
356 |
> |
nstarget = sr.rweight/minweight; |
357 |
> |
if (nstarget > 1) { |
358 |
> |
d = 1./nstarget; |
359 |
> |
scalecolor(sr.rcoef, d); |
360 |
|
sr.rweight *= d; |
361 |
|
} else |
362 |
< |
ns2go = 1; |
362 |
> |
nstarget = 1; |
363 |
|
} |
364 |
< |
dimlist[ndims++] = (int)np->mp; |
365 |
< |
for (niter = ns2go*MAXITER; (ns2go > 0) & (niter > 0); niter--) { |
366 |
< |
if (specjitter > 1.5) |
364 |
> |
setcolor(scol, 0., 0., 0.); |
365 |
> |
dimlist[ndims++] = (int)(size_t)np->mp; |
366 |
> |
maxiter = MAXITER*nstarget; |
367 |
> |
for (nstaken = ntrials = 0; nstaken < nstarget && |
368 |
> |
ntrials < maxiter; ntrials++) { |
369 |
> |
if (ntrials) |
370 |
|
d = frandom(); |
371 |
|
else |
372 |
|
d = urand(ilhash(dimlist,ndims)+samplendx); |
389 |
|
h[i] = np->pnorm[i] + |
390 |
|
d*(cosp*np->u[i] + sinp*np->v[i]); |
391 |
|
d = -2.0 * DOT(h, r->rdir) / (1.0 + d*d); |
395 |
– |
if (d <= np->pdot + FTINY) |
396 |
– |
continue; |
392 |
|
VSUM(sr.rdir, r->rdir, h, d); |
393 |
< |
if (DOT(sr.rdir, r->ron) <= FTINY) |
393 |
> |
/* sample rejection test */ |
394 |
> |
if ((d = DOT(sr.rdir, r->ron)) <= FTINY) |
395 |
|
continue; |
396 |
|
checknorm(sr.rdir); |
397 |
< |
if (specjitter > 1.5) { /* adjusted W-G-M-D weight */ |
398 |
< |
d = 2.*(1. - np->pdot/d); |
399 |
< |
copycolor(sr.rcoef, scol); |
400 |
< |
scalecolor(sr.rcoef, d); |
401 |
< |
rayclear(&sr); |
397 |
> |
if (nstarget > 1) { /* W-G-M-D adjustment */ |
398 |
> |
if (nstaken) rayclear(&sr); |
399 |
> |
rayvalue(&sr); |
400 |
> |
d = 2./(1. + r->rod/d); |
401 |
> |
scalecolor(sr.rcol, d); |
402 |
> |
addcolor(scol, sr.rcol); |
403 |
> |
} else { |
404 |
> |
rayvalue(&sr); |
405 |
> |
multcolor(sr.rcol, sr.rcoef); |
406 |
> |
addcolor(r->rcol, sr.rcol); |
407 |
|
} |
408 |
< |
rayvalue(&sr); |
408 |
< |
multcolor(sr.rcol, sr.rcoef); |
409 |
< |
addcolor(r->rcol, sr.rcol); |
410 |
< |
--ns2go; |
408 |
> |
++nstaken; |
409 |
|
} |
410 |
+ |
if (nstarget > 1) { /* final W-G-M-D weighting */ |
411 |
+ |
multcolor(scol, sr.rcoef); |
412 |
+ |
d = (double)nstarget/ntrials; |
413 |
+ |
scalecolor(scol, d); |
414 |
+ |
addcolor(r->rcol, scol); |
415 |
+ |
} |
416 |
|
ndims--; |
417 |
|
} |
418 |
|
/* compute transmission */ |
420 |
|
scalecolor(sr.rcoef, np->tspec); |
421 |
|
if ((np->specfl & (SP_TRAN|SP_TBLT)) == SP_TRAN && |
422 |
|
rayorigin(&sr, SPECULAR, r, sr.rcoef) == 0) { |
423 |
< |
ns2go = 1; |
423 |
> |
nstarget = 1; |
424 |
|
if (specjitter > 1.5) { /* multiple samples? */ |
425 |
< |
ns2go = specjitter*r->rweight + .5; |
426 |
< |
if (sr.rweight <= minweight*ns2go) |
427 |
< |
ns2go = sr.rweight/minweight; |
428 |
< |
if (ns2go > 1) { |
429 |
< |
d = 1./ns2go; |
425 |
> |
nstarget = specjitter*r->rweight + .5; |
426 |
> |
if (sr.rweight <= minweight*nstarget) |
427 |
> |
nstarget = sr.rweight/minweight; |
428 |
> |
if (nstarget > 1) { |
429 |
> |
d = 1./nstarget; |
430 |
|
scalecolor(sr.rcoef, d); |
431 |
|
sr.rweight *= d; |
432 |
|
} else |
433 |
< |
ns2go = 1; |
433 |
> |
nstarget = 1; |
434 |
|
} |
435 |
< |
dimlist[ndims++] = (int)np->mp; |
436 |
< |
for (niter = ns2go*MAXITER; (ns2go > 0) & (niter > 0); niter--) { |
437 |
< |
if (specjitter > 1.5) |
435 |
> |
dimlist[ndims++] = (int)(size_t)np->mp; |
436 |
> |
maxiter = MAXITER*nstarget; |
437 |
> |
for (nstaken = ntrials = 0; nstaken < nstarget && |
438 |
> |
ntrials < maxiter; ntrials++) { |
439 |
> |
if (ntrials) |
440 |
|
d = frandom(); |
441 |
|
else |
442 |
|
d = urand(ilhash(dimlist,ndims)+1823+samplendx); |
461 |
|
if (DOT(sr.rdir, r->ron) >= -FTINY) |
462 |
|
continue; |
463 |
|
normalize(sr.rdir); /* OK, normalize */ |
464 |
< |
if (specjitter > 1.5) /* multi-sampling */ |
464 |
> |
if (nstaken) /* multi-sampling */ |
465 |
|
rayclear(&sr); |
466 |
|
rayvalue(&sr); |
467 |
|
multcolor(sr.rcol, sr.rcoef); |
468 |
|
addcolor(r->rcol, sr.rcol); |
469 |
< |
--ns2go; |
469 |
> |
++nstaken; |
470 |
|
} |
471 |
|
ndims--; |
472 |
|
} |