extern OBJREC * /* find an object's actual material */
findmaterial(register OBJREC *o)
{
while (!ismaterial(o->otype)) {
if (o->otype == MOD_ALIAS && o->oargs.nsargs) {
OBJECT aobj;
OBJREC *ao;
aobj = lastmod(objndx(o), o->oargs.sarg[0]);
if (aobj < 0)
objerror(o, USER, "bad reference");
ao = objptr(aobj);
if (ismaterial(ao->otype))
return(ao);
if (ao->otype == MOD_ALIAS) {
o = ao;
continue;
}
}
if (o->omod == OVOID)
return(NULL);
o = objptr(o->omod);
}
return(o); /* mixtures will return NULL */
}
OBJREC *
findmaterial(OBJREC *o) /* find an object's actual material */
{
while (!ismaterial(o->otype)) {
if (o->otype == MOD_ALIAS && o->oargs.nsargs) {
OBJECT aobj;
OBJREC *ao;
aobj = lastmod(objndx(o), o->oargs.sarg[0]);
if (aobj < 0)
objerror(o, USER, "bad reference");
/* recursive check on alias branch */
if ((ao = findmaterial(objptr(aobj))) != NULL)
return(ao);
}
if (o->omod == OVOID) {
/* void mixture de facto material? */
if (ismixture(o->otype))
break;
return(NULL); /* else no material found */
}
o = objptr(o->omod);
}
return(o);
}
extern int
sourcehit( /* check to see if ray hit distant source */
register RAY *r
)
{
int glowsrc = -1;
int transrc = -1;
int first, last;
register int i;
if (r->rsrc >= 0) { /* check only one if aimed */
first = last = r->rsrc;
} else { /* otherwise check all */
first = 0; last = nsources-1;
}
for (i = first; i <= last; i++) {
if ((source[i].sflags & (SDISTANT|SVIRTUAL)) != SDISTANT)
continue;
/*
* Check to see if ray is within
* solid angle of source.
*/
if (2.*PI*(1. - DOT(source[i].sloc,r->rdir)) > source[i].ss2)
continue;
/* is it the only possibility? */
if (first == last) {
r->ro = source[i].so;
break;
}
/*
* If it's a glow or transparent illum, just remember it.
*/
if (source[i].sflags & SSKIP) {
if (glowsrc < 0)
glowsrc = i;
continue;
}
if (transillum(source[i].so->omod)) {
if (transrc < 0)
transrc = i;
continue;
}
r->ro = source[i].so; /* otherwise, use first hit */
break;
}
/*
* Do we need fallback?
*/
if (r->ro == NULL) {
if (transrc >= 0 && r->crtype & (AMBIENT|SPECULAR))
return(0); /* avoid overcounting */
if (glowsrc >= 0)
r->ro = source[glowsrc].so;
else
return(0); /* nothing usable */
}
/*
* Make assignments.
*/
r->robj = objndx(r->ro);
for (i = 0; i < 3; i++)
r->ron[i] = -r->rdir[i];
r->rod = 1.0;
r->pert[0] = r->pert[1] = r->pert[2] = 0.0;
r->uv[0] = r->uv[1] = 0.0;
r->rox = NULL;
return(1);
}
