| 93 |
|
colval(ro->cext,RED) : colval(ro->cext,GRN); |
| 94 |
|
if (colval(ro->cext,BLU) < re) re = colval(ro->cext,BLU); |
| 95 |
|
re *= ro->rot; |
| 96 |
< |
if (re > .1) |
| 97 |
< |
r->rweight *= exp(-re); |
| 96 |
> |
if (re > 0.1) |
| 97 |
> |
if (re > 92.) |
| 98 |
> |
r->rweight = 0.0; |
| 99 |
> |
else |
| 100 |
> |
r->rweight *= exp(-re); |
| 101 |
|
} |
| 102 |
|
rayclear(r); |
| 103 |
+ |
if (r->rweight <= 0.0) /* check for expiration */ |
| 104 |
+ |
return(-1); |
| 105 |
+ |
if (r->crtype & SHADOW) /* shadow commitment */ |
| 106 |
+ |
return(0); |
| 107 |
|
if (maxdepth <= 0 && rc != NULL) { /* Russian roulette */ |
| 108 |
|
if (minweight <= 0.0) |
| 109 |
|
error(USER, "zero ray weight in Russian roulette"); |
| 111 |
|
return(-1); /* upper reflection limit */ |
| 112 |
|
if (r->rweight >= minweight) |
| 113 |
|
return(0); |
| 114 |
< |
if (frandom() < r->rweight/minweight) |
| 114 |
> |
if (frandom() > r->rweight/minweight) |
| 115 |
|
return(-1); |
| 116 |
|
rw = minweight/r->rweight; /* promote survivor */ |
| 117 |
|
scalecolor(r->rcoef, rw); |
| 301 |
|
foremat = backmat = 0; |
| 302 |
|
/* foreground */ |
| 303 |
|
fr = *r; |
| 304 |
< |
if (coef > FTINY) |
| 304 |
> |
if (coef > FTINY) { |
| 305 |
> |
scalecolor(fr.rcoef, coef); |
| 306 |
|
foremat = rayshade(&fr, fore); |
| 307 |
+ |
} |
| 308 |
|
/* background */ |
| 309 |
|
br = *r; |
| 310 |
< |
if (coef < 1.0-FTINY) |
| 310 |
> |
if (coef < 1.0-FTINY) { |
| 311 |
> |
scalecolor(br.rcoef, 1.0-coef); |
| 312 |
|
backmat = rayshade(&br, back); |
| 313 |
+ |
} |
| 314 |
|
/* check for transparency */ |
| 315 |
|
if (backmat ^ foremat) { |
| 316 |
|
if (backmat && coef > FTINY) |
| 357 |
|
|
| 358 |
|
extern void |
| 359 |
|
raycontrib( /* compute (cumulative) ray contribution */ |
| 360 |
< |
COLOR rc, |
| 360 |
> |
double rc[3], |
| 361 |
|
const RAY *r, |
| 362 |
|
int flags |
| 363 |
|
) |
| 364 |
|
{ |
| 365 |
< |
COLOR eext, ext1; |
| 366 |
< |
|
| 356 |
< |
setcolor(eext, 0., 0., 0.); |
| 357 |
< |
setcolor(rc, 1., 1., 1.); |
| 365 |
> |
double eext[3]; |
| 366 |
> |
int i; |
| 367 |
|
|
| 368 |
+ |
eext[0] = eext[1] = eext[2] = 0.; |
| 369 |
+ |
rc[0] = rc[1] = rc[2] = 1.; |
| 370 |
+ |
|
| 371 |
|
while (r != NULL && r->crtype&flags) { |
| 372 |
< |
multcolor(rc, r->rcoef); |
| 373 |
< |
copycolor(ext1, r->cext); |
| 374 |
< |
scalecolor(ext1, r->rot); |
| 375 |
< |
addcolor(eext, ext1); |
| 372 |
> |
for (i = 3; i--; ) { |
| 373 |
> |
rc[i] *= colval(r->rcoef,i); |
| 374 |
> |
eext[i] += r->rot * colval(r->cext,i); |
| 375 |
> |
} |
| 376 |
|
r = r->parent; |
| 377 |
|
} |
| 378 |
< |
if (intens(eext) > FTINY) { |
| 379 |
< |
setcolor(ext1, exp(-colval(eext,RED)), |
| 380 |
< |
exp(-colval(eext,GRN)), |
| 369 |
< |
exp(-colval(eext,BLU))); |
| 370 |
< |
multcolor(rc, ext1); |
| 371 |
< |
} |
| 378 |
> |
for (i = 3; i--; ) |
| 379 |
> |
rc[i] *= (eext[i] <= FTINY) ? 1. : |
| 380 |
> |
(eext[i] > 92.) ? 0. : exp(-eext[i]); |
| 381 |
|
} |
| 382 |
|
|
| 383 |
|
|
