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 */
}
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);
}
extern void
raytrans( /* transmit ray as is */
RAY *r
)
{
RAY tr;
if (rayorigin(&tr, TRANS, r, NULL) == 0) {
VCOPY(tr.rdir, r->rdir);
rayvalue(&tr);
copycolor(r->rcol, tr.rcol);
r->rt = r->rot + tr.rt;
}
}
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 int
srcray( /* send a ray to a source, return domega */
register RAY *sr, /* returned source ray */
RAY *r, /* ray which hit object */
SRCINDEX *si /* source sample index */
)
{
double d; /* distance to source */
register SRCREC *srcp;
rayorigin(sr, SHADOW, r, NULL); /* ignore limits */
if (r == NULL)
sr->rmax = 0.0;
while ((d = nextssamp(sr, si)) != 0.0) {
sr->rsrc = si->sn; /* remember source */
srcp = source + si->sn;
if (srcp->sflags & SDISTANT) {
if (srcp->sflags & SSPOT && spotout(sr, srcp->sl.s))
continue;
return(1); /* sample OK */
}
/* local source */
/* check proximity */
if (srcp->sflags & SPROX && d > srcp->sl.prox)
continue;
/* check angle */
if (srcp->sflags & SSPOT) {
if (spotout(sr, srcp->sl.s))
continue;
/* adjust solid angle */
si->dom *= d*d;
d += srcp->sl.s->flen;
si->dom /= d*d;
}
return(1); /* sample OK */
}
return(0); /* no more samples */
}
int
m_dielectric( /* color a ray which hit a dielectric interface */
OBJREC *m,
RAY *r
)
{
double cos1, cos2, nratio;
COLOR ctrans;
COLOR talb;
int hastexture;
int flatsurface;
double refl, trans;
FVECT dnorm;
double d1, d2;
RAY p;
int i;
/* PMAP: skip refracted shadow or ambient ray if accounted for in
photon map */
if (shadowRayInPmap(r) || ambRayInPmap(r))
return(1);
if (m->oargs.nfargs != (m->otype==MAT_DIELECTRIC ? 5 : 8))
objerror(m, USER, "bad arguments");
raytexture(r, m->omod); /* get modifiers */
if ( (hastexture = DOT(r->pert,r->pert) > FTINY*FTINY) )
cos1 = raynormal(dnorm, r); /* perturb normal */
else {
VCOPY(dnorm, r->ron);
cos1 = r->rod;
}
flatsurface = r->ro != NULL && isflat(r->ro->otype) &&
!hastexture | (r->crtype & AMBIENT);
/* index of refraction */
if (m->otype == MAT_DIELECTRIC)
nratio = m->oargs.farg[3] + m->oargs.farg[4]/MLAMBDA;
else
nratio = m->oargs.farg[3] / m->oargs.farg[7];
if (cos1 < 0.0) { /* inside */
hastexture = -hastexture;
cos1 = -cos1;
dnorm[0] = -dnorm[0];
dnorm[1] = -dnorm[1];
dnorm[2] = -dnorm[2];
setcolor(r->cext, -mylog(m->oargs.farg[0]*colval(r->pcol,RED)),
-mylog(m->oargs.farg[1]*colval(r->pcol,GRN)),
-mylog(m->oargs.farg[2]*colval(r->pcol,BLU)));
setcolor(r->albedo, 0., 0., 0.);
r->gecc = 0.;
if (m->otype == MAT_INTERFACE) {
setcolor(ctrans,
-mylog(m->oargs.farg[4]*colval(r->pcol,RED)),
-mylog(m->oargs.farg[5]*colval(r->pcol,GRN)),
-mylog(m->oargs.farg[6]*colval(r->pcol,BLU)));
setcolor(talb, 0., 0., 0.);
} else {
copycolor(ctrans, cextinction);
copycolor(talb, salbedo);
}
} else { /* outside */
nratio = 1.0 / nratio;
setcolor(ctrans, -mylog(m->oargs.farg[0]*colval(r->pcol,RED)),
-mylog(m->oargs.farg[1]*colval(r->pcol,GRN)),
-mylog(m->oargs.farg[2]*colval(r->pcol,BLU)));
setcolor(talb, 0., 0., 0.);
if (m->otype == MAT_INTERFACE) {
setcolor(r->cext,
-mylog(m->oargs.farg[4]*colval(r->pcol,RED)),
-mylog(m->oargs.farg[5]*colval(r->pcol,GRN)),
-mylog(m->oargs.farg[6]*colval(r->pcol,BLU)));
setcolor(r->albedo, 0., 0., 0.);
r->gecc = 0.;
}
}
d2 = 1.0 - nratio*nratio*(1.0 - cos1*cos1); /* compute cos theta2 */
if (d2 < FTINY) /* total reflection */
refl = 1.0;
else { /* refraction occurs */
/* compute Fresnel's equations */
cos2 = sqrt(d2);
d1 = cos1;
d2 = nratio*cos2;
d1 = (d1 - d2) / (d1 + d2);
refl = d1 * d1;
d1 = 1.0 / cos1;
d2 = nratio / cos2;
d1 = (d1 - d2) / (d1 + d2);
refl += d1 * d1;
refl *= 0.5;
trans = 1.0 - refl;
trans *= nratio*nratio; /* solid angle ratio */
setcolor(p.rcoef, trans, trans, trans);
if (rayorigin(&p, REFRACTED, r, p.rcoef) == 0) {
/* compute refracted ray */
d1 = nratio*cos1 - cos2;
for (i = 0; i < 3; i++)
p.rdir[i] = nratio*r->rdir[i] + d1*dnorm[i];
/* accidental reflection? */
if (hastexture &&
DOT(p.rdir,r->ron)*hastexture >= -FTINY) {
d1 *= (double)hastexture;
for (i = 0; i < 3; i++) /* ignore texture */
p.rdir[i] = nratio*r->rdir[i] +
d1*r->ron[i];
normalize(p.rdir); /* not exact */
} else
checknorm(p.rdir);
#ifdef DISPERSE
if (m->otype != MAT_DIELECTRIC
|| r->rod > 0.0
|| r->crtype & SHADOW
|| !directvis
|| m->oargs.farg[4] == 0.0
|| !disperse(m, r, p.rdir,
trans, ctrans, talb))
#endif
{
copycolor(p.cext, ctrans);
copycolor(p.albedo, talb);
rayvalue(&p);
multcolor(p.rcol, p.rcoef);
addcolor(r->rcol, p.rcol);
/* virtual distance */
if (flatsurface ||
(1.-FTINY <= nratio) &
(nratio <= 1.+FTINY))
r->rxt = r->rot + raydistance(&p);
}
}
}
setcolor(p.rcoef, refl, refl, refl);
if (!(r->crtype & SHADOW) &&
rayorigin(&p, REFLECTED, r, p.rcoef) == 0) {
/* compute reflected ray */
VSUM(p.rdir, r->rdir, dnorm, 2.*cos1);
/* accidental penetration? */
if (hastexture && DOT(p.rdir,r->ron)*hastexture <= FTINY)
VSUM(p.rdir, r->rdir, r->ron, 2.*r->rod);
checknorm(p.rdir);
rayvalue(&p); /* reflected ray value */
multcolor(p.rcol, p.rcoef); /* color contribution */
copycolor(r->mcol, p.rcol);
addcolor(r->rcol, p.rcol);
/* virtual distance */
r->rmt = r->rot;
if (flatsurface)
r->rmt += raydistance(&p);
}
/* rayvalue() computes absorption */
return(1);
}
int
m_brdf( /* color a ray that hit a BRDTfunc material */
OBJREC *m,
RAY *r
)
{
int hitfront = 1;
BRDFDAT nd;
RAY sr;
double mirtest=0, mirdist=0;
double transtest=0, transdist=0;
int hasrefl, hastrans;
int hastexture;
COLOR ctmp;
FVECT vtmp;
double d;
MFUNC *mf;
int i;
/* check arguments */
if ((m->oargs.nsargs < 10) | (m->oargs.nfargs < 9))
objerror(m, USER, "bad # arguments");
nd.mp = m;
nd.pr = r;
/* dummy values */
nd.rspec = nd.tspec = 1.0;
nd.trans = 0.5;
/* diffuse reflectance */
if (r->rod > 0.0)
setcolor(nd.rdiff, m->oargs.farg[0],
m->oargs.farg[1],
m->oargs.farg[2]);
else
setcolor(nd.rdiff, m->oargs.farg[3],
m->oargs.farg[4],
m->oargs.farg[5]);
/* diffuse transmittance */
setcolor(nd.tdiff, m->oargs.farg[6],
m->oargs.farg[7],
m->oargs.farg[8]);
/* get modifiers */
raytexture(r, m->omod);
hastexture = DOT(r->pert,r->pert) > FTINY*FTINY;
if (hastexture) { /* perturb normal */
nd.pdot = raynormal(nd.pnorm, r);
} else {
VCOPY(nd.pnorm, r->ron);
nd.pdot = r->rod;
}
if (r->rod < 0.0) { /* orient perturbed values */
nd.pdot = -nd.pdot;
for (i = 0; i < 3; i++) {
nd.pnorm[i] = -nd.pnorm[i];
r->pert[i] = -r->pert[i];
}
hitfront = 0;
}
copycolor(nd.mcolor, r->pcol); /* get pattern color */
multcolor(nd.rdiff, nd.mcolor); /* modify diffuse values */
multcolor(nd.tdiff, nd.mcolor);
hasrefl = bright(nd.rdiff) > FTINY;
hastrans = bright(nd.tdiff) > FTINY;
/* load cal file */
nd.dp = NULL;
mf = getfunc(m, 9, 0x3f, 0);
/* compute transmitted ray */
setbrdfunc(&nd);
errno = 0;
setcolor(ctmp, evalue(mf->ep[3]),
evalue(mf->ep[4]),
evalue(mf->ep[5]));
if ((errno == EDOM) | (errno == ERANGE))
objerror(m, WARNING, "compute error");
else if (rayorigin(&sr, TRANS, r, ctmp) == 0) {
if (!(r->crtype & SHADOW) && hastexture) {
/* perturb direction */
VSUM(sr.rdir, r->rdir, r->pert, -.75);
if (normalize(sr.rdir) == 0.0) {
objerror(m, WARNING, "illegal perturbation");
VCOPY(sr.rdir, r->rdir);
}
} else {
VCOPY(sr.rdir, r->rdir);
}
rayvalue(&sr);
multcolor(sr.rcol, sr.rcoef);
addcolor(r->rcol, sr.rcol);
if (!hastexture) {
transtest = 2.0*bright(sr.rcol);
transdist = r->rot + sr.rt;
}
}
if (r->crtype & SHADOW) /* the rest is shadow */
return(1);
/* compute reflected ray */
setbrdfunc(&nd);
errno = 0;
setcolor(ctmp, evalue(mf->ep[0]),
evalue(mf->ep[1]),
evalue(mf->ep[2]));
if ((errno == EDOM) | (errno == ERANGE))
objerror(m, WARNING, "compute error");
else if (rayorigin(&sr, REFLECTED, r, ctmp) == 0) {
VSUM(sr.rdir, r->rdir, nd.pnorm, 2.*nd.pdot);
checknorm(sr.rdir);
rayvalue(&sr);
multcolor(sr.rcol, sr.rcoef);
addcolor(r->rcol, sr.rcol);
if (!hastexture && r->ro != NULL && isflat(r->ro->otype)) {
mirtest = 2.0*bright(sr.rcol);
mirdist = r->rot + sr.rt;
}
}
/* compute ambient */
if (hasrefl) {
if (!hitfront)
flipsurface(r);
copycolor(ctmp, nd.rdiff);
multambient(ctmp, r, nd.pnorm);
addcolor(r->rcol, ctmp); /* add to returned color */
if (!hitfront)
flipsurface(r);
}
if (hastrans) { /* from other side */
if (hitfront)
flipsurface(r);
vtmp[0] = -nd.pnorm[0];
vtmp[1] = -nd.pnorm[1];
vtmp[2] = -nd.pnorm[2];
copycolor(ctmp, nd.tdiff);
multambient(ctmp, r, vtmp);
addcolor(r->rcol, ctmp);
if (hitfront)
flipsurface(r);
}
if (hasrefl | hastrans || m->oargs.sarg[6][0] != '0')
direct(r, dirbrdf, &nd); /* add direct component */
d = bright(r->rcol); /* set effective distance */
if (transtest > d)
r->rt = transdist;
else if (mirtest > d)
r->rt = mirdist;
return(1);
}
extern void /* add sources smaller than rad to computed subimage */
drawsources(
COLOR *pic[], /* subimage pixel value array */
float *zbf[], /* subimage distance array (opt.) */
int x0, /* origin and size of subimage */
int xsiz,
int y0,
int ysiz
)
{
RREAL spoly[MAXVERT][2], ppoly[MAXVERT][2];
int nsv, npv;
int xmin, xmax, ymin, ymax, x, y;
RREAL cxy[2];
double w;
RAY sr;
register SPLIST *sp;
register int i;
/* check each source in our list */
for (sp = sphead; sp != NULL; sp = sp->next) {
/* clip source poly to subimage */
nsv = box_clip_poly(sp->vl, sp->nv,
(double)x0/hres, (double)(x0+xsiz)/hres,
(double)y0/vres, (double)(y0+ysiz)/vres, spoly);
if (!nsv)
continue;
/* find common subimage (BBox) */
xmin = x0 + xsiz; xmax = x0;
ymin = y0 + ysiz; ymax = y0;
for (i = 0; i < nsv; i++) {
if ((double)xmin/hres > spoly[i][0])
xmin = spoly[i][0]*hres + FTINY;
if ((double)xmax/hres < spoly[i][0])
xmax = spoly[i][0]*hres - FTINY;
if ((double)ymin/vres > spoly[i][1])
ymin = spoly[i][1]*vres + FTINY;
if ((double)ymax/vres < spoly[i][1])
ymax = spoly[i][1]*vres - FTINY;
}
/* evaluate each pixel in BBox */
for (y = ymin; y <= ymax; y++)
for (x = xmin; x <= xmax; x++) {
/* subarea for pixel */
npv = box_clip_poly(spoly, nsv,
(double)x/hres, (x+1.)/hres,
(double)y/vres, (y+1.)/vres,
ppoly);
if (!npv)
continue; /* no overlap */
convex_center(ppoly, npv, cxy);
if ((sr.rmax = viewray(sr.rorg,sr.rdir,&ourview,
cxy[0],cxy[1])) < -FTINY)
continue; /* not in view */
if (source[sp->sn].sflags & SSPOT &&
spotout(&sr, source[sp->sn].sl.s))
continue; /* outside spot */
rayorigin(&sr, SHADOW, NULL, NULL);
sr.rsrc = sp->sn;
rayvalue(&sr); /* compute value */
if (bright(sr.rcol) <= FTINY)
continue; /* missed/blocked */
/* modify pixel */
w = poly_area(ppoly, npv) * hres * vres;
if (zbf[y-y0] != NULL &&
sr.rt < 0.99*zbf[y-y0][x-x0]) {
zbf[y-y0][x-x0] = sr.rt;
} else if (!bigdiff(sr.rcol, pic[y-y0][x-x0],
0.01)) { /* source sample */
scalecolor(pic[y-y0][x-x0], w);
continue;
}
scalecolor(sr.rcol, w);
scalecolor(pic[y-y0][x-x0], 1.-w);
addcolor(pic[y-y0][x-x0], sr.rcol);
}
}
}
static int
redirect( /* compute n'th ray redirection */
OBJREC *m,
RAY *r,
int n
)
{
MFUNC *mf;
EPNODE **va;
FVECT nsdir;
RAY nr;
double coef;
int j;
/* set up function */
mf = getdfunc(m);
setfunc(m, r);
/* assign direction variable */
if (r->rsrc >= 0) {
SRCREC *sp = source + source[r->rsrc].sa.sv.sn;
if (sp->sflags & SDISTANT)
VCOPY(nsdir, sp->sloc);
else {
for (j = 0; j < 3; j++)
nsdir[j] = sp->sloc[j] - r->rop[j];
normalize(nsdir);
}
multv3(nsdir, nsdir, funcxf.xfm);
varset("DxA", '=', nsdir[0]/funcxf.sca);
varset("DyA", '=', nsdir[1]/funcxf.sca);
varset("DzA", '=', nsdir[2]/funcxf.sca);
} else {
varset("DxA", '=', 0.0);
varset("DyA", '=', 0.0);
varset("DzA", '=', 0.0);
}
/* compute coefficient */
errno = 0;
va = mf->ep + 4*n;
coef = evalue(va[0]);
if ((errno == EDOM) | (errno == ERANGE))
goto computerr;
setcolor(nr.rcoef, coef, coef, coef);
if (rayorigin(&nr, TRANS, r, nr.rcoef) < 0)
return(0);
va++; /* compute direction */
for (j = 0; j < 3; j++) {
nr.rdir[j] = evalue(va[j]);
if (errno == EDOM || errno == ERANGE)
goto computerr;
}
if (mf->fxp != &unitxf)
multv3(nr.rdir, nr.rdir, mf->fxp->xfm);
if (r->rox != NULL)
multv3(nr.rdir, nr.rdir, r->rox->f.xfm);
if (normalize(nr.rdir) == 0.0)
goto computerr;
/* compute value */
if (r->rsrc >= 0)
nr.rsrc = source[r->rsrc].sa.sv.sn;
rayvalue(&nr);
multcolor(nr.rcol, nr.rcoef);
addcolor(r->rcol, nr.rcol);
if (r->ro != NULL && isflat(r->ro->otype))
r->rt = r->rot + nr.rt;
return(1);
computerr:
objerror(m, WARNING, "compute error");
return(-1);
}
static int
dir_proj( /* compute a director's projection */
MAT4 pm,
OBJREC *o,
SRCREC *s,
int n
)
{
RAY tr;
OBJREC *m;
MFUNC *mf;
EPNODE **va;
FVECT cent, newdir, nv, h;
double coef, olddot, newdot, od;
int i, j;
/* initialize test ray */
getmaxdisk(cent, o);
if (s->sflags & SDISTANT)
for (i = 0; i < 3; i++) {
tr.rdir[i] = -s->sloc[i];
tr.rorg[i] = cent[i] - tr.rdir[i];
}
else {
for (i = 0; i < 3; i++) {
tr.rdir[i] = cent[i] - s->sloc[i];
tr.rorg[i] = s->sloc[i];
}
if (normalize(tr.rdir) == 0.0)
return(0); /* at source! */
}
od = getplaneq(nv, o);
olddot = DOT(tr.rdir, nv);
if (olddot <= FTINY && olddot >= -FTINY)
return(0); /* old dir parallels plane */
tr.rmax = 0.0;
rayorigin(&tr, PRIMARY, NULL, NULL);
if (!(*ofun[o->otype].funp)(o, &tr))
return(0); /* no intersection! */
/* compute redirection */
m = vsmaterial(o);
mf = getdfunc(m);
setfunc(m, &tr);
varset("DxA", '=', 0.0);
varset("DyA", '=', 0.0);
varset("DzA", '=', 0.0);
errno = 0;
va = mf->ep + 4*n;
coef = evalue(va[0]);
if (errno == EDOM || errno == ERANGE)
goto computerr;
if (coef <= FTINY)
return(0); /* insignificant */
va++;
for (i = 0; i < 3; i++) {
newdir[i] = evalue(va[i]);
if (errno == EDOM || errno == ERANGE)
goto computerr;
}
if (mf->fxp != &unitxf)
multv3(newdir, newdir, mf->fxp->xfm);
/* normalization unnecessary */
newdot = DOT(newdir, nv);
if (newdot <= FTINY && newdot >= -FTINY)
return(0); /* new dir parallels plane */
/* everything OK -- compute shear */
for (i = 0; i < 3; i++)
h[i] = newdir[i]/newdot - tr.rdir[i]/olddot;
setident4(pm);
for (j = 0; j < 3; j++) {
for (i = 0; i < 3; i++)
pm[i][j] += nv[i]*h[j];
pm[3][j] = -od*h[j];
}
if ((newdot > 0.0) ^ (olddot > 0.0)) /* add mirroring */
for (j = 0; j < 3; j++) {
for (i = 0; i < 3; i++)
pm[i][j] -= 2.*nv[i]*nv[j];
pm[3][j] += 2.*od*nv[j];
}
return(1);
computerr:
objerror(m, WARNING, "projection compute error");
return(0);
}
int
m_mist( /* process a ray entering or leaving some mist */
OBJREC *m,
RAY *r
)
{
RAY p;
int *myslist = NULL;
int newslist[MAXSLIST+1];
COLOR mext;
double re, ge, be;
int i, j;
/* check arguments */
if (m->oargs.nfargs > 7)
objerror(m, USER, "bad arguments");
/* get source indices */
if (m->oargs.nsargs > 0 && (myslist = (int *)m->os) == NULL) {
if (m->oargs.nsargs > MAXSLIST)
objerror(m, INTERNAL, "too many sources in list");
myslist = (int *)malloc((m->oargs.nsargs+1)*sizeof(int));
if (myslist == NULL)
goto memerr;
myslist[0] = 0; /* size is first in list */
for (j = 0; j < m->oargs.nsargs; j++) {
i = nsources; /* look up each source id */
while (i--)
if (srcmatch(source+i, m->oargs.sarg[j]))
break;
if (i < 0) {
sprintf(errmsg, "unknown source \"%s\"",
m->oargs.sarg[j]);
objerror(m, WARNING, errmsg);
} else if (inslist(myslist, i)) {
sprintf(errmsg, "duplicate source \"%s\"",
m->oargs.sarg[j]);
objerror(m, WARNING, errmsg);
} else
myslist[++myslist[0]] = i;
}
m->os = (char *)myslist;
}
if (m->oargs.nfargs > 2) { /* compute extinction */
setcolor(mext, m->oargs.farg[0], m->oargs.farg[1],
m->oargs.farg[2]);
raytexture(r, m->omod); /* get modifiers */
multcolor(mext, r->pcol);
} else
setcolor(mext, 0., 0., 0.);
/* start transmitted ray */
if (rayorigin(&p, TRANS, r, NULL) < 0)
return(1);
VCOPY(p.rdir, r->rdir);
p.slights = newslist;
if (r->slights != NULL) /* copy old list if one */
for (j = r->slights[0]; j >= 0; j--)
p.slights[j] = r->slights[j];
else
p.slights[0] = 0;
if (r->rod > 0.) { /* entering ray */
addcolor(p.cext, mext);
if (m->oargs.nfargs > 5)
setcolor(p.albedo, m->oargs.farg[3],
m->oargs.farg[4], m->oargs.farg[5]);
if (m->oargs.nfargs > 6)
p.gecc = m->oargs.farg[6];
add2slist(&p, myslist); /* add to list */
} else { /* leaving ray */
if (myslist != NULL) { /* delete from list */
for (j = myslist[0]; j > 0; j--)
if ( (i = inslist(p.slights, myslist[j])) )
p.slights[i] = -1;
for (i = 0, j = 1; j <= p.slights[0]; j++)
if (p.slights[j] != -1)
p.slights[++i] = p.slights[j];
if (p.slights[0] - i < myslist[0]) { /* fix old */
addcolor(r->cext, mext);
if (m->oargs.nfargs > 5)
setcolor(r->albedo, m->oargs.farg[3],
m->oargs.farg[4], m->oargs.farg[5]);
if (m->oargs.nfargs > 6)
r->gecc = m->oargs.farg[6];
add2slist(r, myslist);
}
p.slights[0] = i;
}
if ((re = colval(r->cext,RED) - colval(mext,RED)) <
colval(cextinction,RED))
re = colval(cextinction,RED);
if ((ge = colval(r->cext,GRN) - colval(mext,GRN)) <
colval(cextinction,GRN))
ge = colval(cextinction,GRN);
if ((be = colval(r->cext,BLU) - colval(mext,BLU)) <
colval(cextinction,BLU))
be = colval(cextinction,BLU);
setcolor(p.cext, re, ge, be);
if (m->oargs.nfargs > 5)
copycolor(p.albedo, salbedo);
if (m->oargs.nfargs > 6)
p.gecc = seccg;
}
rayvalue(&p); /* calls rayparticipate() */
copycolor(r->rcol, p.rcol); /* return value */
r->rt = r->rot + p.rt;
return(1);
memerr:
error(SYSTEM, "out of memory in m_mist");
return 0; /* pro forma return */
}
static void
ashiksamp( /* sample anisotropic Ashikhmin-Shirley specular */
ASHIKDAT *np
)
{
RAY sr;
FVECT h;
double rv[2], dtmp;
double cosph, sinph, costh, sinth;
int maxiter, ntrials, nstarget, nstaken;
int i;
if (np->specfl & SPA_BADU ||
rayorigin(&sr, SPECULAR, np->rp, np->scolor) < 0)
return;
nstarget = 1;
if (specjitter > 1.5) { /* multiple samples? */
nstarget = specjitter*np->rp->rweight + .5;
if (sr.rweight <= minweight*nstarget)
nstarget = sr.rweight/minweight;
if (nstarget > 1) {
dtmp = 1./nstarget;
scalecolor(sr.rcoef, dtmp);
sr.rweight *= dtmp;
} else
nstarget = 1;
}
dimlist[ndims++] = (int)(size_t)np->mp;
maxiter = MAXITER*nstarget;
for (nstaken = ntrials = 0; nstaken < nstarget &&
ntrials < maxiter; ntrials++) {
if (ntrials)
dtmp = frandom();
else
dtmp = urand(ilhash(dimlist,ndims)+647+samplendx);
multisamp(rv, 2, dtmp);
dtmp = 2.*PI * rv[0];
cosph = sqrt(np->v_power + 1.) * tcos(dtmp);
sinph = sqrt(np->u_power + 1.) * tsin(dtmp);
dtmp = 1./sqrt(cosph*cosph + sinph*sinph);
cosph *= dtmp;
sinph *= dtmp;
costh = pow(rv[1], 1./(np->u_power*cosph*cosph+np->v_power*sinph*sinph+1.));
if (costh <= FTINY)
continue;
sinth = sqrt(1. - costh*costh);
for (i = 0; i < 3; i++)
h[i] = cosph*sinth*np->u[i] + sinph*sinth*np->v[i] + costh*np->pnorm[i];
if (nstaken)
rayclear(&sr);
dtmp = -2.*DOT(h, np->rp->rdir);
VSUM(sr.rdir, np->rp->rdir, h, dtmp);
/* sample rejection test */
if (DOT(sr.rdir, np->rp->ron) <= FTINY)
continue;
checknorm(sr.rdir);
rayvalue(&sr);
multcolor(sr.rcol, sr.rcoef);
addcolor(np->rp->rcol, sr.rcol);
++nstaken;
}
ndims--;
}
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++;
}
int
paint( /* compute and paint a rectangle */
PNODE *p
)
{
static RAY thisray;
double h, v;
if ((p->xmax <= p->xmin) | (p->ymax <= p->ymin)) { /* empty */
p->x = p->xmin;
p->y = p->ymin;
setcolor(p->v, 0.0, 0.0, 0.0);
return(0);
}
/* jitter ray direction */
p->x = h = p->xmin + (p->xmax-p->xmin)*frandom();
p->y = v = p->ymin + (p->ymax-p->ymin)*frandom();
if ((thisray.rmax = viewray(thisray.rorg, thisray.rdir, &ourview,
h/hresolu, v/vresolu)) < -FTINY) {
setcolor(thisray.rcol, 0.0, 0.0, 0.0);
} else if (!ray_pnprocs) { /* immediate mode */
ray_trace(&thisray);
} else { /* queuing mode */
int rval;
rayorigin(&thisray, PRIMARY, NULL, NULL);
thisray.rno = (RNUMBER)p;
rval = ray_pqueue(&thisray);
if (!rval)
return(0);
if (rval < 0)
return(-1);
/* get node for returned ray */
p = (PNODE *)thisray.rno;
}
copycolor(p->v, thisray.rcol);
scalecolor(p->v, exposure);
recolor(p); /* paint it */
if (dev->flush != NULL) { /* shall we check for input? */
static RNUMBER lastflush = 0;
RNUMBER counter = raynum;
int flushintvl;
if (!ray_pnprocs) {
counter = nrays;
flushintvl = WFLUSH1;
} else if (ambounce == 0)
flushintvl = ray_pnprocs*WFLUSH;
else if (niflush < WFLUSH)
flushintvl = ray_pnprocs*niflush/(ambounce+1);
else
flushintvl = ray_pnprocs*WFLUSH/(ambounce+1);
if (lastflush > counter)
lastflush = 0; /* counter wrapped */
if (counter - lastflush >= flushintvl) {
lastflush = counter;
(*dev->flush)();
niflush++;
}
}
return(1);
}
static int
ambsample( /* initial ambient division sample */
AMBHEMI *hp,
int i,
int j,
int n
)
{
AMBSAMP *ap = &ambsam(hp,i,j);
RAY ar;
int hlist[3], ii;
double spt[2], zd;
/* generate hemispherical sample */
/* ambient coefficient for weight */
if (ambacc > FTINY)
setcolor(ar.rcoef, AVGREFL, AVGREFL, AVGREFL);
else
copycolor(ar.rcoef, hp->acoef);
if (rayorigin(&ar, AMBIENT, hp->rp, ar.rcoef) < 0)
return(0);
if (ambacc > FTINY) {
multcolor(ar.rcoef, hp->acoef);
scalecolor(ar.rcoef, 1./AVGREFL);
}
hlist[0] = hp->rp->rno;
hlist[1] = j;
hlist[2] = i;
multisamp(spt, 2, urand(ilhash(hlist,3)+n));
resample:
SDsquare2disk(spt, (j+spt[1])/hp->ns, (i+spt[0])/hp->ns);
zd = sqrt(1. - spt[0]*spt[0] - spt[1]*spt[1]);
for (ii = 3; ii--; )
ar.rdir[ii] = spt[0]*hp->ux[ii] +
spt[1]*hp->uy[ii] +
zd*hp->rp->ron[ii];
checknorm(ar.rdir);
/* avoid coincident samples */
if (!n && ambcollision(hp, i, j, ar.rdir)) {
spt[0] = frandom(); spt[1] = frandom();
goto resample; /* reject this sample */
}
dimlist[ndims++] = AI(hp,i,j) + 90171;
rayvalue(&ar); /* evaluate ray */
ndims--;
zd = raydistance(&ar);
if (zd <= FTINY)
return(0); /* should never happen */
multcolor(ar.rcol, ar.rcoef); /* apply coefficient */
if (zd*ap->d < 1.0) /* new/closer distance? */
ap->d = 1.0/zd;
if (!n) { /* record first vertex & value */
if (zd > 10.0*thescene.cusize + 1000.)
zd = 10.0*thescene.cusize + 1000.;
VSUM(ap->p, ar.rorg, ar.rdir, zd);
copycolor(ap->v, ar.rcol);
} else { /* else update recorded value */
hp->acol[RED] -= colval(ap->v,RED);
hp->acol[GRN] -= colval(ap->v,GRN);
hp->acol[BLU] -= colval(ap->v,BLU);
zd = 1.0/(double)(n+1);
scalecolor(ar.rcol, zd);
zd *= (double)n;
scalecolor(ap->v, zd);
addcolor(ap->v, ar.rcol);
}
addcolor(hp->acol, ap->v); /* add to our sum */
return(1);
}
static void
agaussamp( /* sample anisotropic Gaussian specular */
ANISODAT *np
)
{
RAY sr;
FVECT h;
double rv[2];
double d, sinp, cosp;
COLOR scol;
int maxiter, ntrials, nstarget, nstaken;
int i;
/* compute reflection */
if ((np->specfl & (SP_REFL|SP_RBLT)) == SP_REFL &&
rayorigin(&sr, SPECULAR, np->rp, np->scolor) == 0) {
nstarget = 1;
if (specjitter > 1.5) { /* multiple samples? */
nstarget = specjitter*np->rp->rweight + .5;
if (sr.rweight <= minweight*nstarget)
nstarget = sr.rweight/minweight;
if (nstarget > 1) {
d = 1./nstarget;
scalecolor(sr.rcoef, d);
sr.rweight *= d;
} else
nstarget = 1;
}
setcolor(scol, 0., 0., 0.);
dimlist[ndims++] = (int)(size_t)np->mp;
maxiter = MAXITER*nstarget;
for (nstaken = ntrials = 0; nstaken < nstarget &&
ntrials < maxiter; ntrials++) {
if (ntrials)
d = frandom();
else
d = urand(ilhash(dimlist,ndims)+samplendx);
multisamp(rv, 2, d);
d = 2.0*PI * rv[0];
cosp = tcos(d) * np->u_alpha;
sinp = tsin(d) * np->v_alpha;
d = 1./sqrt(cosp*cosp + sinp*sinp);
cosp *= d;
sinp *= d;
if ((0. <= specjitter) & (specjitter < 1.))
rv[1] = 1.0 - specjitter*rv[1];
if (rv[1] <= FTINY)
d = 1.0;
else
d = sqrt(-log(rv[1]) /
(cosp*cosp/(np->u_alpha*np->u_alpha) +
sinp*sinp/(np->v_alpha*np->v_alpha)));
for (i = 0; i < 3; i++)
h[i] = np->pnorm[i] +
d*(cosp*np->u[i] + sinp*np->v[i]);
d = -2.0 * DOT(h, np->rp->rdir) / (1.0 + d*d);
VSUM(sr.rdir, np->rp->rdir, h, d);
/* sample rejection test */
if ((d = DOT(sr.rdir, np->rp->ron)) <= FTINY)
continue;
checknorm(sr.rdir);
if (nstarget > 1) { /* W-G-M-D adjustment */
if (nstaken) rayclear(&sr);
rayvalue(&sr);
d = 2./(1. + np->rp->rod/d);
scalecolor(sr.rcol, d);
addcolor(scol, sr.rcol);
} else {
rayvalue(&sr);
multcolor(sr.rcol, sr.rcoef);
addcolor(np->rp->rcol, sr.rcol);
}
++nstaken;
}
if (nstarget > 1) { /* final W-G-M-D weighting */
multcolor(scol, sr.rcoef);
d = (double)nstarget/ntrials;
scalecolor(scol, d);
addcolor(np->rp->rcol, scol);
}
ndims--;
}
/* compute transmission */
copycolor(sr.rcoef, np->mcolor); /* modify by material color */
scalecolor(sr.rcoef, np->tspec);
if ((np->specfl & (SP_TRAN|SP_TBLT)) == SP_TRAN &&
rayorigin(&sr, SPECULAR, np->rp, sr.rcoef) == 0) {
nstarget = 1;
if (specjitter > 1.5) { /* multiple samples? */
nstarget = specjitter*np->rp->rweight + .5;
if (sr.rweight <= minweight*nstarget)
nstarget = sr.rweight/minweight;
if (nstarget > 1) {
d = 1./nstarget;
scalecolor(sr.rcoef, d);
sr.rweight *= d;
} else
nstarget = 1;
}
dimlist[ndims++] = (int)(size_t)np->mp;
maxiter = MAXITER*nstarget;
for (nstaken = ntrials = 0; nstaken < nstarget &&
ntrials < maxiter; ntrials++) {
if (ntrials)
d = frandom();
else
d = urand(ilhash(dimlist,ndims)+1823+samplendx);
multisamp(rv, 2, d);
d = 2.0*PI * rv[0];
cosp = tcos(d) * np->u_alpha;
sinp = tsin(d) * np->v_alpha;
d = 1./sqrt(cosp*cosp + sinp*sinp);
cosp *= d;
sinp *= d;
if ((0. <= specjitter) & (specjitter < 1.))
rv[1] = 1.0 - specjitter*rv[1];
if (rv[1] <= FTINY)
d = 1.0;
else
d = sqrt(-log(rv[1]) /
(cosp*cosp/(np->u_alpha*np->u_alpha) +
sinp*sinp/(np->v_alpha*np->v_alpha)));
for (i = 0; i < 3; i++)
sr.rdir[i] = np->prdir[i] +
d*(cosp*np->u[i] + sinp*np->v[i]);
if (DOT(sr.rdir, np->rp->ron) >= -FTINY)
continue;
normalize(sr.rdir); /* OK, normalize */
if (nstaken) /* multi-sampling */
rayclear(&sr);
rayvalue(&sr);
multcolor(sr.rcol, sr.rcoef);
addcolor(np->rp->rcol, sr.rcol);
++nstaken;
}
ndims--;
}
}
