| 36 |
|
* hides geometry in front of the surface when rays hit from behind, |
| 37 |
|
* and applies only the transmission and backside reflectance properties. |
| 38 |
|
* Reflection is ignored on the hidden side, as those rays pass through. |
| 39 |
< |
* For the MAT_SBSDF type, we check for a strong "through" component. |
| 39 |
> |
* For the MAT_ABSDF type, we check for a strong "through" component. |
| 40 |
|
* Such a component will cause direct rays to pass through unscattered. |
| 41 |
|
* A separate test prevents over-counting by dropping samples that are |
| 42 |
|
* too close to this "through" direction. BSDFs with such a through direction |
| 43 |
|
* will also have a view component, meaning they are somewhat see-through. |
| 44 |
< |
* A MAT_BSDF type with zero thickness behaves the same as a MAT_SBSDF |
| 44 |
> |
* A MAT_BSDF type with zero thickness behaves the same as a MAT_ABSDF |
| 45 |
|
* type with no strong through component. |
| 46 |
|
* The "up" vector for the BSDF is given by three variables, defined |
| 47 |
|
* (along with the thickness) by the named function file, or '.' if none. |
| 55 |
|
* not multiplied. However, patterns affect this material as a multiplier |
| 56 |
|
* on everything except non-diffuse reflection. |
| 57 |
|
* |
| 58 |
< |
* Arguments for MAT_SBSDF are: |
| 58 |
> |
* Arguments for MAT_ABSDF are: |
| 59 |
|
* 5+ BSDFfile ux uy uz funcfile transform |
| 60 |
|
* 0 |
| 61 |
|
* 0|3|6|9 rdf gdf bdf |
| 86 |
|
RREAL toloc[3][3]; /* world to local BSDF coords */ |
| 87 |
|
RREAL fromloc[3][3]; /* local BSDF coords to world */ |
| 88 |
|
double thick; /* surface thickness */ |
| 89 |
< |
COLOR cthru; /* "through" component for MAT_SBSDF */ |
| 89 |
> |
COLOR cthru; /* "through" component for MAT_ABSDF */ |
| 90 |
|
SDData *sd; /* loaded BSDF data */ |
| 91 |
|
COLOR rdiff; /* diffuse reflection */ |
| 92 |
|
COLOR runsamp; /* BSDF hemispherical reflection */ |
| 96 |
|
|
| 97 |
|
#define cvt_sdcolor(cv, svp) ccy2rgb(&(svp)->spec, (svp)->cieY, cv) |
| 98 |
|
|
| 99 |
< |
/* Compute "through" component color for MAT_SBSDF */ |
| 99 |
> |
/* Compute "through" component color for MAT_ABSDF */ |
| 100 |
|
static void |
| 101 |
|
compute_through(BSDFDAT *ndp) |
| 102 |
|
{ |
| 162 |
|
goto baderror; |
| 163 |
|
if (tomega > 1.5*dfp->minProjSA) |
| 164 |
|
return; /* not really a peak? */ |
| 165 |
– |
tomega /= fabs(pdir[2]); /* remove cosine factor */ |
| 165 |
|
if ((bright(vpeak) - ndp->sd->tLamb.cieY*(1./PI))*tomega <= .001) |
| 166 |
|
return; /* < 0.1% transmission */ |
| 167 |
|
for (i = 3; i--; ) /* remove peak from average */ |
| 235 |
|
diffY = 0; |
| 236 |
|
setcolor(cdiff, 0, 0, 0); |
| 237 |
|
} |
| 238 |
< |
/* need projected solid angles */ |
| 238 |
> |
/* need projected solid angle */ |
| 239 |
|
omega *= fabs(vsrc[2]); |
| 241 |
– |
ec = SDsizeBSDF(&tomega, ndp->vray, vsrc, SDqueryMin, ndp->sd); |
| 242 |
– |
if (ec) |
| 243 |
– |
goto baderror; |
| 240 |
|
/* check indirect over-counting */ |
| 241 |
|
if ((vsrc[2] > 0) ^ (ndp->vray[2] > 0) && bright(ndp->cthru) > FTINY) { |
| 242 |
< |
double dx = vsrc[0] + ndp->vray[0]; |
| 243 |
< |
double dy = vsrc[1] + ndp->vray[1]; |
| 244 |
< |
if (dx*dx + dy*dy <= (2.5*4./PI)*(omega + tomega + |
| 245 |
< |
2.*sqrt(omega*tomega))) |
| 242 |
> |
double dx = vsrc[0] + ndp->vray[0]; |
| 243 |
> |
double dy = vsrc[1] + ndp->vray[1]; |
| 244 |
> |
SDSpectralDF *dfp = (ndp->pr->rod > 0) ? |
| 245 |
> |
((ndp->sd->tf != NULL) ? ndp->sd->tf : ndp->sd->tb) : |
| 246 |
> |
((ndp->sd->tb != NULL) ? ndp->sd->tb : ndp->sd->tf) ; |
| 247 |
> |
|
| 248 |
> |
if (dx*dx + dy*dy <= (2.5*4./PI)*(omega + dfp->minProjSA + |
| 249 |
> |
2.*sqrt(omega*dfp->minProjSA))) |
| 250 |
|
return(0); |
| 251 |
|
} |
| 252 |
+ |
ec = SDsizeBSDF(&tomega, ndp->vray, vsrc, SDqueryMin, ndp->sd); |
| 253 |
+ |
if (ec) |
| 254 |
+ |
goto baderror; |
| 255 |
|
/* assign number of samples */ |
| 256 |
|
sf = specjitter * ndp->pr->rweight; |
| 257 |
|
if (tomega <= 0) |
| 627 |
|
raytrans(r); /* hide our proxy */ |
| 628 |
|
return(1); |
| 629 |
|
} |
| 630 |
+ |
if (hasthick && r->crtype & SHADOW) /* early shadow check #1 */ |
| 631 |
+ |
return(1); |
| 632 |
|
nd.mp = m; |
| 633 |
|
nd.pr = r; |
| 634 |
|
/* get BSDF data */ |
| 635 |
|
nd.sd = loadBSDF(m->oargs.sarg[hasthick]); |
| 636 |
< |
/* early shadow check */ |
| 637 |
< |
if (r->crtype & SHADOW && (nd.sd->tf == NULL) & (nd.sd->tb == NULL)) |
| 636 |
> |
/* early shadow check #2 */ |
| 637 |
> |
if (r->crtype & SHADOW && (nd.sd->tf == NULL) & (nd.sd->tb == NULL)) { |
| 638 |
> |
SDfreeCache(nd.sd); |
| 639 |
|
return(1); |
| 640 |
+ |
} |
| 641 |
|
/* diffuse reflectance */ |
| 642 |
|
if (hitfront) { |
| 643 |
|
cvt_sdcolor(nd.rdiff, &nd.sd->rLambFront); |
| 693 |
|
} |
| 694 |
|
if (ec) { |
| 695 |
|
objerror(m, WARNING, "Illegal orientation vector"); |
| 696 |
+ |
SDfreeCache(nd.sd); |
| 697 |
|
return(1); |
| 698 |
|
} |
| 699 |
|
setcolor(nd.cthru, 0, 0, 0); /* consider through component */ |
| 700 |
< |
if (m->otype == MAT_SBSDF) { |
| 700 |
> |
if (m->otype == MAT_ABSDF) { |
| 701 |
|
compute_through(&nd); |
| 702 |
|
if (r->crtype & SHADOW) { |
| 703 |
|
RAY tr; /* attempt to pass shadow ray */ |
| 704 |
+ |
SDfreeCache(nd.sd); |
| 705 |
|
if (rayorigin(&tr, TRANS, r, nd.cthru) < 0) |
| 706 |
|
return(1); /* no through component */ |
| 707 |
|
VCOPY(tr.rdir, r->rdir); |
