void
getfocus( /* set focus distance */
char *s
)
{
char buf[64];
double dist;
if (sscanf(s, "%lf", &dist) < 1) {
int x, y;
RAY thisray;
if (dev->getcur == NULL)
return;
(*dev->comout)("Pick focus point\n");
if ((*dev->getcur)(&x, &y) == ABORT)
return;
if ((thisray.rmax = viewray(thisray.rorg, thisray.rdir,
&ourview, (x+.5)/hresolu, (y+.5)/vresolu)) < -FTINY) {
error(COMMAND, "not on image");
return;
}
rayorigin(&thisray, PRIMARY, NULL, NULL);
if (!localhit(&thisray, &thescene)) {
error(COMMAND, "not a local object");
return;
}
dist = thisray.rot;
} else if (dist <= .0) {
error(COMMAND, "focus distance must be positive");
return;
}
ourview.vdist = dist;
sprintf(buf, "Focus distance set to %f\n", dist);
(*dev->comout)(buf);
}
static int /* cast source ray to first blocker */
castshadow(int sn, FVECT rorg, FVECT rdir)
{
RAY rt;
VCOPY(rt.rorg, rorg);
VCOPY(rt.rdir, rdir);
rt.rmax = 0;
rayorigin(&rt, PRIMARY, NULL, NULL);
/* check for intersection */
while (localhit(&rt, &thescene)) {
RAY rt1 = rt; /* pretend we were aimed at source */
rt1.crtype |= rt1.rtype = SHADOW;
rt1.rdir[0] = -rt.rdir[0];
rt1.rdir[1] = -rt.rdir[1];
rt1.rdir[2] = -rt.rdir[2];
rt1.rod = -rt.rod;
VSUB(rt1.rorg, rt.rop, rt.rdir);
rt1.rot = 1.;
rt1.rsrc = sn;
/* record blocker */
if (srcblocker(&rt1))
return(1);
/* move past failed blocker */
VSUM(rt.rorg, rt.rop, rt.rdir, FTINY);
rayclear(&rt); /* & try again... */
}
return(0); /* found no blockers */
}
extern int
o_instance( /* compute ray intersection with octree */
OBJREC *o,
register RAY *r
)
{
RAY rcont;
double d;
register INSTANCE *ins;
register int i;
/* get the octree */
ins = getinstance(o, IO_ALL);
/* copy and transform ray */
rcont = *r;
multp3(rcont.rorg, r->rorg, ins->x.b.xfm);
multv3(rcont.rdir, r->rdir, ins->x.b.xfm);
for (i = 0; i < 3; i++)
rcont.rdir[i] /= ins->x.b.sca;
rcont.rmax *= ins->x.b.sca;
/* clear and trace it */
rayclear(&rcont);
if (!localhit(&rcont, &ins->obj->scube))
return(0); /* missed */
if (rcont.rot * ins->x.f.sca >= r->rot)
return(0); /* not close enough */
if (o->omod != OVOID) { /* if we have modifier, use it */
r->ro = o;
r->rox = NULL;
} else { /* else use theirs */
r->ro = rcont.ro;
if (rcont.rox != NULL) {
newrayxf(r); /* allocate transformation */
/* NOTE: r->rox may equal rcont.rox! */
multmat4(r->rox->f.xfm, rcont.rox->f.xfm, ins->x.f.xfm);
r->rox->f.sca = rcont.rox->f.sca * ins->x.f.sca;
multmat4(r->rox->b.xfm, ins->x.b.xfm, rcont.rox->b.xfm);
r->rox->b.sca = ins->x.b.sca * rcont.rox->b.sca;
} else
r->rox = &ins->x;
}
/* transform it back */
r->rot = rcont.rot * ins->x.f.sca;
multp3(r->rop, rcont.rop, ins->x.f.xfm);
multv3(r->ron, rcont.ron, ins->x.f.xfm);
multv3(r->pert, rcont.pert, ins->x.f.xfm);
d = 1./ins->x.f.sca;
for (i = 0; i < 3; i++) {
r->ron[i] *= d;
r->pert[i] *= d;
}
r->rod = rcont.rod;
r->uv[0] = rcont.uv[0];
r->uv[1] = rcont.uv[1];
/* return hit */
return(1);
}
int
getinterest( /* get area of interest */
char *s,
int direc,
FVECT vec,
double *mp
)
{
int x, y;
RAY thisray;
int i;
if (sscanf(s, "%lf", mp) != 1)
*mp = 1.0;
else if (*mp < -FTINY) /* negative zoom is reduction */
*mp = -1.0 / *mp;
else if (*mp <= FTINY) { /* too small */
error(COMMAND, "illegal magnification");
return(-1);
}
if (!sscanvec(sskip(s), vec)) {
if (dev->getcur == NULL)
return(-1);
(*dev->comout)("Pick view center\n");
if ((*dev->getcur)(&x, &y) == ABORT)
return(-1);
if ((thisray.rmax = viewray(thisray.rorg, thisray.rdir,
&ourview, (x+.5)/hresolu, (y+.5)/vresolu)) < -FTINY) {
error(COMMAND, "not on image");
return(-1);
}
if (!direc || ourview.type == VT_PAR) {
rayorigin(&thisray, PRIMARY, NULL, NULL);
if (!localhit(&thisray, &thescene)) {
error(COMMAND, "not a local object");
return(-1);
}
}
if (direc)
if (ourview.type == VT_PAR)
for (i = 0; i < 3; i++)
vec[i] = thisray.rop[i] - ourview.vp[i];
else
VCOPY(vec, thisray.rdir);
else
VCOPY(vec, thisray.rop);
} else if (direc) {
for (i = 0; i < 3; i++)
vec[i] -= ourview.vp[i];
if (normalize(vec) == 0.0) {
error(COMMAND, "point at view origin");
return(-1);
}
}
return(0);
}
void
getorigin( /* origin viewpoint */
char *s
)
{
VIEW nv = ourview;
double d;
/* get new view origin */
if (sscanf(s, "%lf %lf", &d, &d) == 1) {
/* just moving some distance */
VSUM(nv.vp, nv.vp, nv.vdir, d);
} else if (!sscanvec(s, nv.vp)) {
int x, y; /* need to pick origin */
RAY thisray;
if (dev->getcur == NULL)
return;
(*dev->comout)("Pick point on surface for new origin\n");
if ((*dev->getcur)(&x, &y) == ABORT)
return;
if ((thisray.rmax = viewray(thisray.rorg, thisray.rdir,
&ourview, (x+.5)/hresolu, (y+.5)/vresolu)) < -FTINY) {
error(COMMAND, "not on image");
return;
}
rayorigin(&thisray, PRIMARY, NULL, NULL);
if (!localhit(&thisray, &thescene)) {
error(COMMAND, "not a local object");
return;
}
if (thisray.rod < 0.0) /* don't look through other side */
flipsurface(&thisray);
VSUM(nv.vp, thisray.rop, thisray.ron, 20.0*FTINY);
VCOPY(nv.vdir, thisray.ron);
} else if (!sscanvec(sskip2(s,3), nv.vdir) || normalize(nv.vdir) == 0.0)
VCOPY(nv.vdir, ourview.vdir);
d = DOT(nv.vdir, nv.vup); /* need different up vector? */
if (d*d >= 1.-2.*FTINY) {
int i;
nv.vup[0] = nv.vup[1] = nv.vup[2] = 0.0;
for (i = 3; i--; )
if (nv.vdir[i]*nv.vdir[i] < 0.34)
break;
nv.vup[i] = 1.;
}
newview(&nv);
}
extern void
raytrace( /* trace a ray and compute its value */
RAY *r
)
{
if (localhit(r, &thescene))
raycont(r); /* hit local surface, evaluate */
else if (r->ro == &Aftplane) {
r->ro = NULL; /* hit aft clipping plane */
r->rot = FHUGE;
} else if (sourcehit(r))
rayshade(r, r->ro->omod); /* distant source */
if (trace != NULL)
(*trace)(r); /* trace execution */
rayparticipate(r); /* for participating medium */
}
extern void
direct( /* add direct component */
RAY *r, /* ray that hit surface */
srcdirf_t *f, /* direct component coefficient function */
void *p /* data for f */
)
{
register int sn;
register CONTRIB *scp;
SRCINDEX si;
int nshadcheck, ncnts;
int nhits;
double prob, ourthresh, hwt;
RAY sr;
/* NOTE: srccnt and cntord global so no recursion */
if (nsources <= 0)
return; /* no sources?! */
/* potential contributions */
initsrcindex(&si);
for (sn = 0; srcray(&sr, r, &si); sn++) {
if (sn >= maxcntr) {
maxcntr = sn + MAXSPART;
srccnt = (CONTRIB *)realloc((void *)srccnt,
maxcntr*sizeof(CONTRIB));
cntord = (CNTPTR *)realloc((void *)cntord,
maxcntr*sizeof(CNTPTR));
if ((srccnt == NULL) | (cntord == NULL))
error(SYSTEM, "out of memory in direct");
}
cntord[sn].sndx = sn;
scp = srccnt + sn;
scp->sno = sr.rsrc;
/* compute coefficient */
(*f)(scp->coef, p, sr.rdir, si.dom);
cntord[sn].brt = intens(scp->coef);
if (cntord[sn].brt <= 0.0)
continue;
#if SHADCACHE
/* check shadow cache */
if (si.np == 1 && srcblocked(&sr)) {
cntord[sn].brt = 0.0;
continue;
}
#endif
VCOPY(scp->dir, sr.rdir);
copycolor(sr.rcoef, scp->coef);
/* compute potential */
sr.revf = srcvalue;
rayvalue(&sr);
multcolor(sr.rcol, sr.rcoef);
copycolor(scp->val, sr.rcol);
cntord[sn].brt = bright(sr.rcol);
}
/* sort contributions */
qsort(cntord, sn, sizeof(CNTPTR), cntcmp);
{ /* find last */
register int l, m;
ncnts = l = sn;
sn = 0;
while ((m = (sn + ncnts) >> 1) != l) {
if (cntord[m].brt > 0.0)
sn = m;
else
ncnts = m;
l = m;
}
}
if (ncnts == 0)
return; /* no contributions! */
/* accumulate tail */
for (sn = ncnts-1; sn > 0; sn--)
cntord[sn-1].brt += cntord[sn].brt;
/* compute number to check */
nshadcheck = pow((double)ncnts, shadcert) + .5;
/* modify threshold */
ourthresh = shadthresh / r->rweight;
/* test for shadows */
for (nhits = 0, hwt = 0.0, sn = 0; sn < ncnts;
hwt += (double)source[scp->sno].nhits /
(double)source[scp->sno].ntests,
sn++) {
/* check threshold */
if ((sn+nshadcheck>=ncnts ? cntord[sn].brt :
cntord[sn].brt-cntord[sn+nshadcheck].brt)
< ourthresh*bright(r->rcol))
break;
scp = srccnt + cntord[sn].sndx;
/* test for hit */
rayorigin(&sr, SHADOW, r, NULL);
copycolor(sr.rcoef, scp->coef);
VCOPY(sr.rdir, scp->dir);
sr.rsrc = scp->sno;
/* keep statistics */
if (source[scp->sno].ntests++ > 0xfffffff0) {
source[scp->sno].ntests >>= 1;
source[scp->sno].nhits >>= 1;
}
if (localhit(&sr, &thescene) &&
( sr.ro != source[scp->sno].so ||
source[scp->sno].sflags & SFOLLOW )) {
/* follow entire path */
raycont(&sr);
if (trace != NULL)
(*trace)(&sr); /* trace execution */
if (bright(sr.rcol) <= FTINY) {
#if SHADCACHE
if ((scp <= srccnt || scp[-1].sno != scp->sno)
&& (scp >= srccnt+ncnts-1 ||
scp[1].sno != scp->sno))
srcblocker(&sr);
#endif
continue; /* missed! */
}
rayparticipate(&sr);
multcolor(sr.rcol, sr.rcoef);
copycolor(scp->val, sr.rcol);
} else if (trace != NULL &&
(source[scp->sno].sflags & (SDISTANT|SVIRTUAL|SFOLLOW))
== (SDISTANT|SFOLLOW) &&
sourcehit(&sr) && rayshade(&sr, sr.ro->omod)) {
(*trace)(&sr); /* trace execution */
/* skip call to rayparticipate() & scp->val update */
}
/* add contribution if hit */
addcolor(r->rcol, scp->val);
nhits++;
source[scp->sno].nhits++;
}
