extern int
raymixture( /* mix modifiers */
RAY *r,
OBJECT fore,
OBJECT back,
double coef
)
{
RAY fr, br;
int foremat, backmat;
int i;
/* bound coefficient */
if (coef > 1.0)
coef = 1.0;
else if (coef < 0.0)
coef = 0.0;
/* compute foreground and background */
foremat = backmat = 0;
/* foreground */
fr = *r;
if (coef > FTINY) {
fr.rweight *= coef;
scalecolor(fr.rcoef, coef);
foremat = rayshade(&fr, fore);
}
/* background */
br = *r;
if (coef < 1.0-FTINY) {
br.rweight *= 1.0-coef;
scalecolor(br.rcoef, 1.0-coef);
backmat = rayshade(&br, back);
}
/* check for transparency */
if (backmat ^ foremat) {
if (backmat && coef > FTINY)
raytrans(&fr);
else if (foremat && coef < 1.0-FTINY)
raytrans(&br);
}
/* mix perturbations */
for (i = 0; i < 3; i++)
r->pert[i] = coef*fr.pert[i] + (1.0-coef)*br.pert[i];
/* mix pattern colors */
scalecolor(fr.pcol, coef);
scalecolor(br.pcol, 1.0-coef);
copycolor(r->pcol, fr.pcol);
addcolor(r->pcol, br.pcol);
/* return value tells if material */
if (!foremat & !backmat)
return(0);
/* mix returned ray values */
scalecolor(fr.rcol, coef);
scalecolor(br.rcol, 1.0-coef);
copycolor(r->rcol, fr.rcol);
addcolor(r->rcol, br.rcol);
r->rt = bright(fr.rcol) > bright(br.rcol) ? fr.rt : br.rt;
return(1);
}
static void
dirashik( /* compute source contribution */
COLOR cval, /* returned coefficient */
void *nnp, /* material data */
FVECT ldir, /* light source direction */
double omega /* light source size */
)
{
ASHIKDAT *np = nnp;
double ldot;
double dtmp, dtmp1, dtmp2;
FVECT h;
COLOR ctmp;
setcolor(cval, 0.0, 0.0, 0.0);
ldot = DOT(np->pnorm, ldir);
if (ldot < 0.0)
return; /* wrong side */
/*
* Compute and add diffuse reflected component to returned
* color.
*/
copycolor(ctmp, np->mcolor);
dtmp = ldot * omega * (1.0/PI) * (1. - schlick_fres(ldot));
scalecolor(ctmp, dtmp);
addcolor(cval, ctmp);
if ((np->specfl & (SPA_REFL|SPA_BADU)) != SPA_REFL)
return;
/*
* Compute specular reflection coefficient
*/
/* half vector */
VSUB(h, ldir, np->rp->rdir);
normalize(h);
/* ellipse */
dtmp1 = DOT(np->u, h);
dtmp1 *= dtmp1 * np->u_power;
dtmp2 = DOT(np->v, h);
dtmp2 *= dtmp2 * np->v_power;
/* Ashikhmin-Shirley model*/
dtmp = DOT(np->pnorm, h);
dtmp = pow(dtmp, (dtmp1+dtmp2)/(1.-dtmp*dtmp));
dtmp *= sqrt((np->u_power+1.)*(np->v_power+1.));
dtmp /= 8.*PI * DOT(ldir,h) * MAX(ldot,np->pdot);
/* worth using? */
if (dtmp > FTINY) {
copycolor(ctmp, np->scolor);
dtmp *= ldot * omega;
scalecolor(ctmp, dtmp);
addcolor(cval, ctmp);
}
}
extern void
rayparticipate( /* compute ray medium participation */
RAY *r
)
{
COLOR ce, ca;
double re, ge, be;
if (intens(r->cext) <= 1./FHUGE)
return; /* no medium */
re = r->rot*colval(r->cext,RED);
ge = r->rot*colval(r->cext,GRN);
be = r->rot*colval(r->cext,BLU);
if (r->crtype & SHADOW) { /* no scattering for sources */
re *= 1. - colval(r->albedo,RED);
ge *= 1. - colval(r->albedo,GRN);
be *= 1. - colval(r->albedo,BLU);
}
setcolor(ce, re<=FTINY ? 1. : re>92. ? 0. : exp(-re),
ge<=FTINY ? 1. : ge>92. ? 0. : exp(-ge),
be<=FTINY ? 1. : be>92. ? 0. : exp(-be));
multcolor(r->rcol, ce); /* path extinction */
if (r->crtype & SHADOW || intens(r->albedo) <= FTINY)
return; /* no scattering */
setcolor(ca,
colval(r->albedo,RED)*colval(ambval,RED)*(1.-colval(ce,RED)),
colval(r->albedo,GRN)*colval(ambval,GRN)*(1.-colval(ce,GRN)),
colval(r->albedo,BLU)*colval(ambval,BLU)*(1.-colval(ce,BLU)));
addcolor(r->rcol, ca); /* ambient in scattering */
srcscatter(r); /* source in scattering */
}
extern void
scotscan( /* apply scotopic color sensitivity loss */
COLOR *scan,
int xres
)
{
COLOR ctmp;
double incolor, b, Lw;
register int i;
for (i = 0; i < xres; i++) {
Lw = plum(scan[i]);
if (Lw >= TopMesopic)
incolor = 1.;
else if (Lw <= BotMesopic)
incolor = 0.;
else
incolor = (Lw - BotMesopic) /
(TopMesopic - BotMesopic);
if (incolor < 1.-FTINY) {
b = (1.-incolor)*slum(scan[i])*inpexp/SWNORM;
if (lumf == rgblum) b /= WHTEFFICACY;
setcolor(ctmp, b, b, b);
if (incolor <= FTINY)
setcolor(scan[i], 0., 0., 0.);
else
scalecolor(scan[i], incolor);
addcolor(scan[i], ctmp);
}
}
}
static void
sum_consp( /* sum in conspicuity result */
register struct ConspSum *cdest,
register struct ConspSum *cs
)
{
if ((cdest == NULL) | (cs == NULL))
return;
addcolor(cdest->vsum, cs->vsum);
addcolor(cdest->v2sum, cs->v2sum);
cdest->nsamp += cs->nsamp;
cdest->xmsum += cs->xmsum;
cdest->ymsum += cs->ymsum;
cdest->npix += cs->npix;
if (cs->hls > cdest->hls)
cdest->hls = cs->hls;
}
static void
starpoint( /* pixel is on the star's point */
COLOR fcol,
int x,
int y,
register HOTPIX *hp
)
{
COLOR ctmp;
double d2;
d2 = (double)(x - hp->x)*(x - hp->x) + (double)(y - hp->y)*(y - hp->y);
if (d2 > sprdfact) {
d2 = sprdfact / d2;
if (d2 < FTINY)
return;
copycolor(ctmp, hp->val);
scalecolor(ctmp, d2);
addcolor(fcol, ctmp);
} else if (d2 > FTINY) {
addcolor(fcol, hp->val);
}
}
FormulaParser::FormulaParser(std::string const& descr, FormatFlags flags, AttributeMap const& values, PowerTag* context)
: descr(descr)
, flags(flags)
, values(values)
, pos(0)
, context(context)
{
if (!preloaded) {
preloaded = true;
addcolor("blue");
addcolor("magic", "blue");
addcolor("gray");
addcolor("gold");
addcolor("green");
addcolor("orange");
addcolor("purple");
addcolor("red");
addcolor("white");
addcolor("yellow");
pretags.emplace("/c", "</span>");
pretags.emplace("icon:bullet", "<span class=\"tooltip-icon-bullet\"></span>");
}
}
static void
getpicture(void) /* load in picture colors */
{
COLR *scanln;
COLOR pval;
int ccount[24];
double d;
int y, i;
register int x;
scanln = (COLR *)malloc(xmax*sizeof(COLR));
if (scanln == NULL) {
perror(progname);
exit(1);
}
for (i = 0; i < 24; i++) {
setcolor(inpRGB[i], 0., 0., 0.);
ccount[i] = 0;
}
for (y = ymax-1; y >= 0; y--) {
if (freadcolrs(scanln, xmax, stdin) < 0) {
fprintf(stderr, "%s: error reading input picture\n",
progname);
exit(1);
}
for (x = 0; x < xmax; x++)
if (chartndx(x, y, &i) == RG_CENT) {
colr_color(pval, scanln[x]);
addcolor(inpRGB[i], pval);
ccount[i]++;
}
}
for (i = 0; i < 24; i++) { /* compute averages */
if (ccount[i] == 0)
continue;
d = 1./ccount[i];
scalecolor(inpRGB[i], d);
inpflags |= 1L<<i;
}
free((void *)scanln);
}
extern void
dobox( /* simple box filter */
COLOR csum,
int xcent,
int ycent,
int c,
int r
)
{
int wsum;
double d;
int y;
register int x, offs;
register COLOR *scan;
wsum = 0;
setcolor(csum, 0.0, 0.0, 0.0);
for (y = ycent+1-ybrad; y <= ycent+ybrad; y++) {
if (y < 0) continue;
if (y >= yres) break;
d = y_r < 1.0 ? y_r*y - (r+.5) : (double)(y - ycent);
if (d < -0.5) continue;
if (d >= 0.5) break;
scan = scanin[y%barsize];
for (x = xcent+1-xbrad; x <= xcent+xbrad; x++) {
offs = x < 0 ? xres : x >= xres ? -xres : 0;
if (offs && !wrapfilt)
continue;
d = x_c < 1.0 ? x_c*x - (c+.5) : (double)(x - xcent);
if (d < -0.5) continue;
if (d >= 0.5) break;
wsum++;
addcolor(csum, scan[x+offs]);
}
}
if (wsum > 1) {
d = 1.0/wsum;
scalecolor(csum, d);
}
}
void
compavg( /* recompute averages */
PNODE *p
)
{
int i, navg;
if (p->kid == NULL)
return;
setcolor(p->v, .0, .0, .0);
navg = 0;
for (i = 0; i < 4; i++) {
if (p->kid[i].xmin >= p->kid[i].xmax) continue;
if (p->kid[i].ymin >= p->kid[i].ymax) continue;
compavg(p->kid+i);
addcolor(p->v, p->kid[i].v);
navg++;
}
if (navg > 1)
scalecolor(p->v, 1./navg);
}
extern void
dogauss( /* gaussian filter */
COLOR csum,
int xcent,
int ycent,
int c,
int r
)
{
double dy, dx, weight, wsum;
COLOR ctmp;
int y;
register int x, offs;
register COLOR *scan;
wsum = FTINY;
setcolor(csum, 0.0, 0.0, 0.0);
for (y = ycent-yrad; y <= ycent+yrad; y++) {
if (y < 0) continue;
if (y >= yres) break;
dy = (y_r*(y+.5) - (r+.5))/rad;
scan = scanin[y%barsize];
for (x = xcent-xrad; x <= xcent+xrad; x++) {
offs = x < 0 ? xres : x >= xres ? -xres : 0;
if (offs && !wrapfilt)
continue;
dx = (x_c*(x+.5) - (c+.5))/rad;
weight = lookgauss(dx*dx + dy*dy);
wsum += weight;
copycolor(ctmp, scan[x+offs]);
scalecolor(ctmp, weight);
addcolor(csum, ctmp);
}
}
weight = 1.0/wsum;
scalecolor(csum, weight);
}
char *
material(void) /* get (and print) current material */
{
char *mname = "mat";
COLOR radrgb, c2;
double d;
if (c_cmname != NULL)
mname = c_cmname;
if (!c_cmaterial->clock)
return(mname); /* already current */
/* else update output */
c_cmaterial->clock = 0;
if (c_cmaterial->ed > .1) { /* emitter */
cvtcolor(radrgb, &c_cmaterial->ed_c,
emult*c_cmaterial->ed/(PI*WHTEFFICACY));
if (glowdist < FHUGE) { /* do a glow */
fprintf(matfp, "\nvoid glow %s\n0\n0\n", mname);
fprintf(matfp, "4 %f %f %f %f\n", colval(radrgb,RED),
colval(radrgb,GRN),
colval(radrgb,BLU), glowdist);
} else {
fprintf(matfp, "\nvoid light %s\n0\n0\n", mname);
fprintf(matfp, "3 %f %f %f\n", colval(radrgb,RED),
colval(radrgb,GRN),
colval(radrgb,BLU));
}
return(mname);
}
d = c_cmaterial->rd + c_cmaterial->td +
c_cmaterial->rs + c_cmaterial->ts;
if ((d < 0.) | (d > 1.))
return(NULL);
/* check for glass/dielectric */
if (c_cmaterial->nr > 1.1 &&
c_cmaterial->ts > .25 && c_cmaterial->rs <= .125 &&
c_cmaterial->td <= .01 && c_cmaterial->rd <= .01 &&
c_cmaterial->rs_a <= .01 && c_cmaterial->ts_a <= .01) {
cvtcolor(radrgb, &c_cmaterial->ts_c,
c_cmaterial->ts + c_cmaterial->rs);
if (c_cmaterial->sided) { /* dielectric */
colval(radrgb,RED) = pow(colval(radrgb,RED),
1./C_1SIDEDTHICK);
colval(radrgb,GRN) = pow(colval(radrgb,GRN),
1./C_1SIDEDTHICK);
colval(radrgb,BLU) = pow(colval(radrgb,BLU),
1./C_1SIDEDTHICK);
fprintf(matfp, "\nvoid dielectric %s\n0\n0\n", mname);
fprintf(matfp, "5 %g %g %g %f 0\n", colval(radrgb,RED),
colval(radrgb,GRN), colval(radrgb,BLU),
c_cmaterial->nr);
return(mname);
}
/* glass */
fprintf(matfp, "\nvoid glass %s\n0\n0\n", mname);
fprintf(matfp, "4 %f %f %f %f\n", colval(radrgb,RED),
colval(radrgb,GRN), colval(radrgb,BLU),
c_cmaterial->nr);
return(mname);
}
/* check for trans */
if (c_cmaterial->td > .01 || c_cmaterial->ts > .01) {
double ts, a5, a6;
if (c_cmaterial->sided) {
ts = sqrt(c_cmaterial->ts); /* approximate */
a5 = .5;
} else {
ts = c_cmaterial->ts;
a5 = 1.;
}
/* average colors */
d = c_cmaterial->rd + c_cmaterial->td + ts;
cvtcolor(radrgb, &c_cmaterial->rd_c, c_cmaterial->rd/d);
cvtcolor(c2, &c_cmaterial->td_c, c_cmaterial->td/d);
addcolor(radrgb, c2);
cvtcolor(c2, &c_cmaterial->ts_c, ts/d);
addcolor(radrgb, c2);
if (c_cmaterial->rs + ts > .0001)
a5 = (c_cmaterial->rs*c_cmaterial->rs_a +
ts*a5*c_cmaterial->ts_a) /
(c_cmaterial->rs + ts);
a6 = (c_cmaterial->td + ts) /
(c_cmaterial->rd + c_cmaterial->td + ts);
if (a6 < .999)
d = c_cmaterial->rd/(1. - c_cmaterial->rs)/(1. - a6);
else
d = c_cmaterial->td + ts;
scalecolor(radrgb, d);
fprintf(matfp, "\nvoid trans %s\n0\n0\n", mname);
fprintf(matfp, "7 %f %f %f\n", colval(radrgb,RED),
colval(radrgb,GRN), colval(radrgb,BLU));
fprintf(matfp, "\t%f %f %f %f\n", c_cmaterial->rs, a5, a6,
ts/(ts + c_cmaterial->td));
return(mname);
}
/* check for plastic */
if (c_cmaterial->rs < .1) {
cvtcolor(radrgb, &c_cmaterial->rd_c,
c_cmaterial->rd/(1.-c_cmaterial->rs));
fprintf(matfp, "\nvoid plastic %s\n0\n0\n", mname);
fprintf(matfp, "5 %f %f %f %f %f\n", colval(radrgb,RED),
colval(radrgb,GRN), colval(radrgb,BLU),
c_cmaterial->rs, c_cmaterial->rs_a);
return(mname);
}
/* else it's metal */
/* average colors */
cvtcolor(radrgb, &c_cmaterial->rd_c, c_cmaterial->rd);
cvtcolor(c2, &c_cmaterial->rs_c, c_cmaterial->rs);
addcolor(radrgb, c2);
fprintf(matfp, "\nvoid metal %s\n0\n0\n", mname);
fprintf(matfp, "5 %f %f %f %f %f\n", colval(radrgb,RED),
colval(radrgb,GRN), colval(radrgb,BLU),
c_cmaterial->rs/(c_cmaterial->rd + c_cmaterial->rs),
c_cmaterial->rs_a);
return(mname);
}
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
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);
}
static int
disperse( /* check light sources for dispersion */
OBJREC *m,
RAY *r,
FVECT vt,
double tr,
COLOR cet,
COLOR abt
)
{
RAY sray;
const RAY *entray;
FVECT v1, v2, n1, n2;
FVECT dv, v2Xdv;
double v2Xdvv2Xdv;
int success = 0;
SRCINDEX si;
FVECT vtmp1, vtmp2;
double dtmp1, dtmp2;
int l1, l2;
COLOR ctmp;
int i;
/*
* This routine computes dispersion to the first order using
* the following assumptions:
*
* 1) The dependency of the index of refraction on wavelength
* is approximated by Hartmann's equation with lambda0
* equal to zero.
* 2) The entry and exit locations are constant with respect
* to dispersion.
*
* The second assumption permits us to model dispersion without
* having to sample refracted directions. We assume that the
* geometry inside the material is constant, and concern ourselves
* only with the relationship between the entering and exiting ray.
* We compute the first derivatives of the entering and exiting
* refraction with respect to the index of refraction. This
* is then used in a first order Taylor series to determine the
* index of refraction necessary to send the exiting ray to each
* light source.
* If an exiting ray hits a light source within the refraction
* boundaries, we sum all the frequencies over the disc of the
* light source to determine the resulting color. A smaller light
* source will therefore exhibit a sharper spectrum.
*/
if (!(r->crtype & REFRACTED)) { /* ray started in material */
VCOPY(v1, r->rdir);
n1[0] = -r->rdir[0]; n1[1] = -r->rdir[1]; n1[2] = -r->rdir[2];
} else {
/* find entry point */
for (entray = r; entray->rtype != REFRACTED;
entray = entray->parent)
;
entray = entray->parent;
if (entray->crtype & REFRACTED) /* too difficult */
return(0);
VCOPY(v1, entray->rdir);
VCOPY(n1, entray->ron);
}
VCOPY(v2, vt); /* exiting ray */
VCOPY(n2, r->ron);
/* first order dispersion approx. */
dtmp1 = 1./DOT(n1, v1);
dtmp2 = 1./DOT(n2, v2);
for (i = 0; i < 3; i++)
dv[i] = v1[i] + v2[i] - n1[i]*dtmp1 - n2[i]*dtmp2;
if (DOT(dv, dv) <= FTINY) /* null effect */
return(0);
/* compute plane normal */
fcross(v2Xdv, v2, dv);
v2Xdvv2Xdv = DOT(v2Xdv, v2Xdv);
/* check sources */
initsrcindex(&si);
while (srcray(&sray, r, &si)) {
if (DOT(sray.rdir, v2) < MINCOS)
continue; /* bad source */
/* adjust source ray */
dtmp1 = DOT(v2Xdv, sray.rdir) / v2Xdvv2Xdv;
sray.rdir[0] -= dtmp1 * v2Xdv[0];
sray.rdir[1] -= dtmp1 * v2Xdv[1];
sray.rdir[2] -= dtmp1 * v2Xdv[2];
l1 = lambda(m, v2, dv, sray.rdir); /* mean lambda */
if (l1 > MAXLAMBDA || l1 < MINLAMBDA) /* not visible */
continue;
/* trace source ray */
copycolor(sray.cext, cet);
copycolor(sray.albedo, abt);
normalize(sray.rdir);
rayvalue(&sray);
if (bright(sray.rcol) <= FTINY) /* missed it */
continue;
/*
* Compute spectral sum over diameter of source.
* First find directions for rays going to opposite
* sides of source, then compute wavelengths for each.
*/
fcross(vtmp1, v2Xdv, sray.rdir);
dtmp1 = sqrt(si.dom / v2Xdvv2Xdv / PI);
/* compute first ray */
VSUM(vtmp2, sray.rdir, vtmp1, dtmp1);
l1 = lambda(m, v2, dv, vtmp2); /* first lambda */
if (l1 < 0)
continue;
/* compute second ray */
VSUM(vtmp2, sray.rdir, vtmp1, -dtmp1);
l2 = lambda(m, v2, dv, vtmp2); /* second lambda */
if (l2 < 0)
continue;
/* compute color from spectrum */
if (l1 < l2)
spec_rgb(ctmp, l1, l2);
else
spec_rgb(ctmp, l2, l1);
multcolor(ctmp, sray.rcol);
scalecolor(ctmp, tr);
addcolor(r->rcol, ctmp);
success++;
}
return(success);
}
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
sumans( /* sum input pixel to output */
int px,
int py,
int rcent,
int ccent,
double m
)
{
double dy2, dx;
COLOR pval, ctmp;
int ksiz, r, offs;
double pc, pr, norm;
register int i, c;
register COLOR *scan;
/*
* This normalization method fails at the picture borders because
* a different number of input pixels contribute there.
*/
scan = scanin[py%barsize] + (px < 0 ? xres : px >= xres ? -xres : 0);
copycolor(pval, scan[px]);
pc = x_c*(px+.5);
pr = y_r*(py+.5);
ksiz = CHECKRAD*m*rad + 1;
if (ksiz > orad) ksiz = orad;
/* compute normalization */
norm = 0.0;
i = 0;
for (r = rcent-ksiz; r <= rcent+ksiz; r++) {
if (r < 0) continue;
if (r >= nrows) break;
dy2 = (pr - (r+.5))/(m*rad);
dy2 *= dy2;
for (c = ccent-ksiz; c <= ccent+ksiz; c++) {
if (!wrapfilt) {
if (c < 0) continue;
if (c >= ncols) break;
}
dx = (pc - (c+.5))/(m*rad);
norm += warr[i++] = lookgauss(dx*dx + dy2);
}
}
norm = 1.0/norm;
if (x_c < 1.0) norm *= x_c;
if (y_r < 1.0) norm *= y_r;
/* sum pixels */
i = 0;
for (r = rcent-ksiz; r <= rcent+ksiz; r++) {
if (r < 0) continue;
if (r >= nrows) break;
scan = scoutbar[r%obarsize];
for (c = ccent-ksiz; c <= ccent+ksiz; c++) {
offs = c < 0 ? ncols : c >= ncols ? -ncols : 0;
if (offs && !wrapfilt)
continue;
copycolor(ctmp, pval);
dx = norm*warr[i++];
scalecolor(ctmp, dx);
addcolor(scan[c+offs], ctmp);
}
}
}
void volumePhotonDensity (PhotonMap *pmap, RAY *ray, COLOR irrad)
/* Photon volume density estimate. Returns irradiance at ray -> rop. */
{
unsigned i;
float r2, gecc2, ph;
COLOR flux;
Photon *photon;
const PhotonSearchQueueNode *sqn;
setcolor(irrad, 0, 0, 0);
if (!pmap -> maxGather)
return;
findPhotons(pmap, ray);
/* Need at least 2 photons */
if (pmap -> squeue.tail < 2)
return;
#if 0
/* Volume biascomp disabled (probably redundant) */
if (pmap -> minGather == pmap -> maxGather)
#endif
{
/* No bias compensation. Just do a plain vanilla estimate */
gecc2 = ray -> gecc * ray -> gecc;
sqn = pmap -> squeue.node + 1;
/* Average radius^2 between furthest two photons to improve accuracy */
r2 = max(sqn -> dist2, (sqn + 1) -> dist2);
r2 = 0.25 * (pmap -> maxDist2 + r2 + 2 * sqrt(pmap -> maxDist2 * r2));
/* Skip the extra photon */
for (i = 1; i < pmap -> squeue.tail; i++, sqn++) {
photon = getNearestPhoton(&pmap -> squeue, sqn -> idx);
/* Compute phase function for inscattering from photon */
if (gecc2 <= FTINY)
ph = 1;
else {
ph = DOT(ray -> rdir, photon -> norm) / 127;
ph = 1 + gecc2 - 2 * ray -> gecc * ph;
ph = (1 - gecc2) / (ph * sqrt(ph));
}
getPhotonFlux(photon, flux);
scalecolor(flux, ph);
addcolor(irrad, flux);
}
/* Divide by search volume 4 / 3 * PI * r^3 and phase function
normalization factor 1 / (4 * PI) */
scalecolor(irrad, 3 / (16 * PI * PI * r2 * sqrt(r2)));
return;
}
#if 0
else
/* Apply bias compensation to density estimate */
volumeBiasComp(pmap, ray, irrad);
#endif
}
static void
diraniso( /* compute source contribution */
COLOR cval, /* returned coefficient */
void *nnp, /* material data */
FVECT ldir, /* light source direction */
double omega /* light source size */
)
{
ANISODAT *np = nnp;
double ldot;
double dtmp, dtmp1, dtmp2;
FVECT h;
double au2, av2;
COLOR ctmp;
setcolor(cval, 0.0, 0.0, 0.0);
ldot = DOT(np->pnorm, ldir);
if (ldot < 0.0 ? np->trans <= FTINY : np->trans >= 1.0-FTINY)
return; /* wrong side */
if ((ldot > FTINY) & (np->rdiff > FTINY)) {
/*
* Compute and add diffuse reflected component to returned
* color. The diffuse reflected component will always be
* modified by the color of the material.
*/
copycolor(ctmp, np->mcolor);
dtmp = ldot * omega * np->rdiff * (1.0/PI);
scalecolor(ctmp, dtmp);
addcolor(cval, ctmp);
}
if (ldot > FTINY && np->specfl&SP_REFL) {
/*
* Compute specular reflection coefficient using
* anisotropic Gaussian distribution model.
*/
/* add source width if flat */
if (np->specfl & SP_FLAT)
au2 = av2 = omega * (0.25/PI);
else
au2 = av2 = 0.0;
au2 += np->u_alpha*np->u_alpha;
av2 += np->v_alpha*np->v_alpha;
/* half vector */
VSUB(h, ldir, np->rp->rdir);
/* ellipse */
dtmp1 = DOT(np->u, h);
dtmp1 *= dtmp1 / au2;
dtmp2 = DOT(np->v, h);
dtmp2 *= dtmp2 / av2;
/* new W-G-M-D model */
dtmp = DOT(np->pnorm, h);
dtmp *= dtmp;
dtmp1 = (dtmp1 + dtmp2) / dtmp;
dtmp = exp(-dtmp1) * DOT(h,h) /
(PI * dtmp*dtmp * sqrt(au2*av2));
/* worth using? */
if (dtmp > FTINY) {
copycolor(ctmp, np->scolor);
dtmp *= ldot * omega;
scalecolor(ctmp, dtmp);
addcolor(cval, ctmp);
}
}
if ((ldot < -FTINY) & (np->tdiff > FTINY)) {
/*
* Compute diffuse transmission.
*/
copycolor(ctmp, np->mcolor);
dtmp = -ldot * omega * np->tdiff * (1.0/PI);
scalecolor(ctmp, dtmp);
addcolor(cval, ctmp);
}
if (ldot < -FTINY && np->specfl&SP_TRAN) {
/*
* Compute specular transmission. Specular transmission
* is always modified by material color.
*/
/* roughness + source */
au2 = av2 = omega * (1.0/PI);
au2 += np->u_alpha*np->u_alpha;
av2 += np->v_alpha*np->v_alpha;
/* "half vector" */
VSUB(h, ldir, np->prdir);
dtmp = DOT(h,h);
if (dtmp > FTINY*FTINY) {
dtmp1 = DOT(h,np->pnorm);
dtmp = 1.0 - dtmp1*dtmp1/dtmp;
if (dtmp > FTINY*FTINY) {
dtmp1 = DOT(h,np->u);
dtmp1 *= dtmp1 / au2;
dtmp2 = DOT(h,np->v);
dtmp2 *= dtmp2 / av2;
dtmp = (dtmp1 + dtmp2) / dtmp;
}
} else
dtmp = 0.0;
/* Gaussian */
dtmp = exp(-dtmp) * (1.0/PI) * sqrt(-ldot/(np->pdot*au2*av2));
/* worth using? */
if (dtmp > FTINY) {
copycolor(ctmp, np->mcolor);
dtmp *= np->tspec * omega;
scalecolor(ctmp, dtmp);
addcolor(cval, ctmp);
}
}
}
int
m_ashikhmin( /* shade ray that hit something anisotropic */
OBJREC *m,
RAY *r
)
{
ASHIKDAT nd;
COLOR ctmp;
double fres;
int i;
/* easy shadow test */
if (r->crtype & SHADOW)
return(1);
if (m->oargs.nfargs != 8)
objerror(m, USER, "bad number of real arguments");
/* check for back side */
if (r->rod < 0.0) {
if (!backvis) {
raytrans(r);
return(1);
}
raytexture(r, m->omod);
flipsurface(r); /* reorient if backvis */
} else
raytexture(r, m->omod);
/* get material color */
nd.mp = m;
nd.rp = r;
setcolor(nd.mcolor, m->oargs.farg[0],
m->oargs.farg[1],
m->oargs.farg[2]);
setcolor(nd.scolor, m->oargs.farg[3],
m->oargs.farg[4],
m->oargs.farg[5]);
/* get specular power */
nd.specfl = 0;
nd.u_power = m->oargs.farg[6];
nd.v_power = m->oargs.farg[7];
nd.pdot = raynormal(nd.pnorm, r); /* perturb normal */
if (nd.pdot < .001)
nd.pdot = .001; /* non-zero for dirashik() */
multcolor(nd.mcolor, r->pcol); /* modify diffuse color */
if (bright(nd.scolor) > FTINY) { /* adjust specular color */
nd.specfl |= SPA_REFL;
/* check threshold */
if (specthresh >= bright(nd.scolor)-FTINY)
nd.specfl |= SPA_RBLT;
fres = schlick_fres(nd.pdot); /* Schick's Fresnel approx */
for (i = 0; i < 3; i++)
colval(nd.scolor,i) += (1.-colval(nd.scolor,i))*fres;
}
if (r->ro != NULL && isflat(r->ro->otype))
nd.specfl |= SPA_FLAT;
/* set up coordinates */
getacoords_as(&nd);
/* specular sampling? */
if ((nd.specfl & (SPA_REFL|SPA_RBLT)) == SPA_REFL)
ashiksamp(&nd);
/* diffuse interreflection */
if (bright(nd.mcolor) > FTINY) {
copycolor(ctmp, nd.mcolor); /* modified by material color */
if (nd.specfl & SPA_RBLT) /* add in specular as well? */
addcolor(ctmp, nd.scolor);
multambient(ctmp, r, nd.pnorm);
addcolor(r->rcol, ctmp); /* add to returned color */
}
direct(r, dirashik, &nd); /* add direct component */
return(1);
}
extern double
sumambient( /* get interpolated ambient value */
COLOR acol,
RAY *r,
FVECT rn,
int al,
AMBTREE *at,
FVECT c0,
double s
)
{
double d, e1, e2, wt, wsum;
COLOR ct;
FVECT ck0;
int i;
int j;
AMBVAL *av;
wsum = 0.0;
/* do this node */
for (av = at->alist; av != NULL; av = av->next) {
double rn_dot = -2.0;
if (tracktime)
av->latick = ambclock;
/*
* Ambient level test.
*/
if (av->lvl > al) /* list sorted, so this works */
break;
if (av->weight < 0.9*r->rweight)
continue;
/*
* Ambient radius test.
*/
VSUB(ck0, av->pos, r->rop);
e1 = DOT(ck0, ck0) / (av->rad * av->rad);
if (e1 > ambacc*ambacc*1.21)
continue;
/*
* Direction test using closest normal.
*/
d = DOT(av->dir, r->ron);
if (rn != r->ron) {
rn_dot = DOT(av->dir, rn);
if (rn_dot > 1.0-FTINY)
rn_dot = 1.0-FTINY;
if (rn_dot >= d-FTINY) {
d = rn_dot;
rn_dot = -2.0;
}
}
e2 = (1.0 - d) * r->rweight;
if (e2 < 0.0)
e2 = 0.0;
else if (e1 + e2 > ambacc*ambacc*1.21)
continue;
/*
* Ray behind test.
*/
d = 0.0;
for (j = 0; j < 3; j++)
d += (r->rop[j] - av->pos[j]) *
(av->dir[j] + r->ron[j]);
if (d*0.5 < -minarad*ambacc-.001)
continue;
/*
* Jittering final test reduces image artifacts.
*/
e1 = sqrt(e1);
e2 = sqrt(e2);
wt = e1 + e2;
if (wt > ambacc*(.9+.2*urand(9015+samplendx)))
continue;
/*
* Recompute directional error using perturbed normal
*/
if (rn_dot > 0.0) {
e2 = sqrt((1.0 - rn_dot)*r->rweight);
wt = e1 + e2;
}
if (wt <= 1e-3)
wt = 1e3;
else
wt = 1.0 / wt;
wsum += wt;
extambient(ct, av, r->rop, rn);
scalecolor(ct, wt);
addcolor(acol, ct);
}
if (at->kid == NULL)
return(wsum);
/* do children */
s *= 0.5;
for (i = 0; i < 8; i++) {
for (j = 0; j < 3; j++) {
ck0[j] = c0[j];
if (1<<j & i)
ck0[j] += s;
if (r->rop[j] < ck0[j] - OCTSCALE*s)
break;
if (r->rop[j] > ck0[j] + (1.0+OCTSCALE)*s)
break;
}
if (j == 3)
wsum += sumambient(acol, r, rn, al,
at->kid+i, ck0, s);
}
return(wsum);
}
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--;
}
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
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);
}
void photonDensity (PhotonMap *pmap, RAY *ray, COLOR irrad)
/* Photon density estimate. Returns irradiance at ray -> rop. */
{
unsigned i;
float r2;
COLOR flux;
Photon *photon;
const PhotonSearchQueueNode *sqn;
setcolor(irrad, 0, 0, 0);
if (!pmap -> maxGather)
return;
/* Ignore sources */
if (ray -> ro && islight(objptr(ray -> ro -> omod) -> otype))
return;
findPhotons(pmap, ray);
/* Need at least 2 photons */
if (pmap -> squeue.tail < 2) {
#ifdef PMAP_NONEFOUND
sprintf(errmsg, "no photons found on %s at (%.3f, %.3f, %.3f)",
ray -> ro ? ray -> ro -> oname : "<null>",
ray -> rop [0], ray -> rop [1], ray -> rop [2]);
error(WARNING, errmsg);
#endif
return;
}
if (pmap -> minGather == pmap -> maxGather) {
/* No bias compensation. Just do a plain vanilla estimate */
sqn = pmap -> squeue.node + 1;
/* Average radius^2 between furthest two photons to improve accuracy */
r2 = max(sqn -> dist2, (sqn + 1) -> dist2);
r2 = 0.25 * (pmap -> maxDist2 + r2 + 2 * sqrt(pmap -> maxDist2 * r2));
/* Skip the extra photon */
for (i = 1 ; i < pmap -> squeue.tail; i++, sqn++) {
photon = getNearestPhoton(&pmap -> squeue, sqn -> idx);
getPhotonFlux(photon, flux);
#ifdef PMAP_EPANECHNIKOV
/* Apply Epanechnikov kernel to photon flux based on photon dist */
scalecolor(flux, 2 * (1 - sqn -> dist2 / r2));
#endif
addcolor(irrad, flux);
}
/* Divide by search area PI * r^2, 1 / PI required as ambient
normalisation factor */
scalecolor(irrad, 1 / (PI * PI * r2));
return;
}
else
/* Apply bias compensation to density estimate */
biasComp(pmap, irrad);
}
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);
}
int
m_brdf2( /* color a ray that hit a BRDF material */
OBJREC *m,
RAY *r
)
{
BRDFDAT nd;
COLOR ctmp;
FVECT vtmp;
double dtmp;
/* always a shadow */
if (r->crtype & SHADOW)
return(1);
/* check arguments */
if ((m->oargs.nsargs < (hasdata(m->otype)?4:2)) | (m->oargs.nfargs <
((m->otype==MAT_TFUNC)|(m->otype==MAT_TDATA)?6:4)))
objerror(m, USER, "bad # arguments");
/* check for back side */
if (r->rod < 0.0) {
if (!backvis) {
raytrans(r);
return(1);
}
raytexture(r, m->omod);
flipsurface(r); /* reorient if backvis */
} else
raytexture(r, m->omod);
nd.mp = m;
nd.pr = r;
/* get material color */
setcolor(nd.mcolor, m->oargs.farg[0],
m->oargs.farg[1],
m->oargs.farg[2]);
/* get specular component */
nd.rspec = m->oargs.farg[3];
/* compute transmittance */
if ((m->otype == MAT_TFUNC) | (m->otype == MAT_TDATA)) {
nd.trans = m->oargs.farg[4]*(1.0 - nd.rspec);
nd.tspec = nd.trans * m->oargs.farg[5];
dtmp = nd.trans - nd.tspec;
setcolor(nd.tdiff, dtmp, dtmp, dtmp);
} else {
nd.tspec = nd.trans = 0.0;
setcolor(nd.tdiff, 0.0, 0.0, 0.0);
}
/* compute reflectance */
dtmp = 1.0 - nd.trans - nd.rspec;
setcolor(nd.rdiff, dtmp, dtmp, dtmp);
nd.pdot = raynormal(nd.pnorm, r); /* perturb normal */
multcolor(nd.mcolor, r->pcol); /* modify material color */
multcolor(nd.rdiff, nd.mcolor);
multcolor(nd.tdiff, nd.mcolor);
/* load auxiliary files */
if (hasdata(m->otype)) {
nd.dp = getdata(m->oargs.sarg[1]);
getfunc(m, 2, 0, 0);
} else {
nd.dp = NULL;
getfunc(m, 1, 0, 0);
}
/* compute ambient */
if (nd.trans < 1.0-FTINY) {
copycolor(ctmp, nd.mcolor); /* modified by material color */
scalecolor(ctmp, 1.0-nd.trans);
multambient(ctmp, r, nd.pnorm);
addcolor(r->rcol, ctmp); /* add to returned color */
}
if (nd.trans > FTINY) { /* from other side */
flipsurface(r);
vtmp[0] = -nd.pnorm[0];
vtmp[1] = -nd.pnorm[1];
vtmp[2] = -nd.pnorm[2];
copycolor(ctmp, nd.mcolor);
scalecolor(ctmp, nd.trans);
multambient(ctmp, r, vtmp);
addcolor(r->rcol, ctmp);
flipsurface(r);
}
/* add direct component */
direct(r, dirbrdf, &nd);
return(1);
}
static void
dirbrdf( /* compute source contribution */
COLOR cval, /* returned coefficient */
void *nnp, /* material data */
FVECT ldir, /* light source direction */
double omega /* light source size */
)
{
BRDFDAT *np = nnp;
double ldot;
double dtmp;
COLOR ctmp;
FVECT ldx;
static double vldx[5], pt[MAXDIM];
char **sa;
int i;
#define lddx (vldx+1)
setcolor(cval, 0.0, 0.0, 0.0);
ldot = DOT(np->pnorm, ldir);
if (ldot <= FTINY && ldot >= -FTINY)
return; /* too close to grazing */
if (ldot < 0.0 ? np->trans <= FTINY : np->trans >= 1.0-FTINY)
return; /* wrong side */
if (ldot > 0.0) {
/*
* Compute and add diffuse reflected component to returned
* color. The diffuse reflected component will always be
* modified by the color of the material.
*/
copycolor(ctmp, np->rdiff);
dtmp = ldot * omega / PI;
scalecolor(ctmp, dtmp);
addcolor(cval, ctmp);
} else {
/*
* Diffuse transmitted component.
*/
copycolor(ctmp, np->tdiff);
dtmp = -ldot * omega / PI;
scalecolor(ctmp, dtmp);
addcolor(cval, ctmp);
}
if (ldot > 0.0 ? np->rspec <= FTINY : np->tspec <= FTINY)
return; /* diffuse only */
/* set up function */
setbrdfunc(np);
sa = np->mp->oargs.sarg;
errno = 0;
/* transform light vector */
multv3(ldx, ldir, funcxf.xfm);
for (i = 0; i < 3; i++)
lddx[i] = ldx[i]/funcxf.sca;
lddx[3] = omega;
/* compute BRTDF */
if (np->mp->otype == MAT_BRTDF) {
if (sa[6][0] == '0') /* special case */
colval(ctmp,RED) = 0.0;
else
colval(ctmp,RED) = funvalue(sa[6], 4, lddx);
if (sa[7][0] == '0')
colval(ctmp,GRN) = 0.0;
else if (!strcmp(sa[7],sa[6]))
colval(ctmp,GRN) = colval(ctmp,RED);
else
colval(ctmp,GRN) = funvalue(sa[7], 4, lddx);
if (!strcmp(sa[8],sa[6]))
colval(ctmp,BLU) = colval(ctmp,RED);
else if (!strcmp(sa[8],sa[7]))
colval(ctmp,BLU) = colval(ctmp,GRN);
else
colval(ctmp,BLU) = funvalue(sa[8], 4, lddx);
dtmp = bright(ctmp);
} else if (np->dp == NULL) {
dtmp = funvalue(sa[0], 4, lddx);
setcolor(ctmp, dtmp, dtmp, dtmp);
} else {
for (i = 0; i < np->dp->nd; i++)
pt[i] = funvalue(sa[3+i], 4, lddx);
vldx[0] = datavalue(np->dp, pt);
dtmp = funvalue(sa[0], 5, vldx);
setcolor(ctmp, dtmp, dtmp, dtmp);
}
if ((errno == EDOM) | (errno == ERANGE)) {
objerror(np->mp, WARNING, "compute error");
return;
}
if (dtmp <= FTINY)
return;
if (ldot > 0.0) {
/*
* Compute reflected non-diffuse component.
*/
if ((np->mp->otype == MAT_MFUNC) | (np->mp->otype == MAT_MDATA))
multcolor(ctmp, np->mcolor);
dtmp = ldot * omega * np->rspec;
scalecolor(ctmp, dtmp);
addcolor(cval, ctmp);
} else {
/*
* Compute transmitted non-diffuse component.
*/
if ((np->mp->otype == MAT_TFUNC) | (np->mp->otype == MAT_TDATA))
multcolor(ctmp, np->mcolor);
dtmp = -ldot * omega * np->tspec;
scalecolor(ctmp, dtmp);
addcolor(cval, ctmp);
}
#undef lddx
}
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);
}
}
}
void buildPhotonMap (PhotonMap *pmap, double *photonFlux,
PhotonPrimaryIdx *primaryOfs, unsigned nproc)
{
unsigned long n, nCheck = 0;
unsigned i;
Photon *p;
COLOR flux;
char nuHeapFname [sizeof(PMAP_TMPFNAME)];
FILE *nuHeap;
/* Need double here to reduce summation errors */
double avgFlux [3] = {0, 0, 0}, CoG [3] = {0, 0, 0}, CoGdist = 0;
FVECT d;
if (!pmap)
error(INTERNAL, "undefined photon map in buildPhotonMap");
/* Get number of photons from heapfile size */
if (fseek(pmap -> heap, 0, SEEK_END) < 0)
error(SYSTEM, "failed seek to end of photon heap in buildPhotonMap");
pmap -> numPhotons = ftell(pmap -> heap) / sizeof(Photon);
if (!pmap -> numPhotons)
error(INTERNAL, "empty photon map in buildPhotonMap");
if (!pmap -> heap)
error(INTERNAL, "no heap in buildPhotonMap");
#ifdef DEBUG_PMAP
eputs("Checking photon heap consistency...\n");
checkPhotonHeap(pmap -> heap);
sprintf(errmsg, "Heap contains %ld photons\n", pmap -> numPhotons);
eputs(errmsg);
#endif
/* Allocate heap buffa */
if (!pmap -> heapBuf) {
pmap -> heapBufSize = PMAP_HEAPBUFSIZE;
pmap -> heapBuf = calloc(pmap -> heapBufSize, sizeof(Photon));
if (!pmap -> heapBuf)
error(SYSTEM, "failed to allocate postprocessed photon heap in"
"buildPhotonMap");
}
/* We REALLY don't need yet another @%&*! heap just to hold the scaled
* photons, but can't think of a quicker fix... */
mktemp(strcpy(nuHeapFname, PMAP_TMPFNAME));
if (!(nuHeap = fopen(nuHeapFname, "w+b")))
error(SYSTEM, "failed to open postprocessed photon heap in "
"buildPhotonMap");
rewind(pmap -> heap);
#ifdef DEBUG_PMAP
eputs("Postprocessing photons...\n");
#endif
while (!feof(pmap -> heap)) {
#ifdef DEBUG_PMAP
printf("Reading %lu at %lu... ", pmap -> heapBufSize, ftell(pmap->heap));
#endif
pmap -> heapBufLen = fread(pmap -> heapBuf, sizeof(Photon),
pmap -> heapBufSize, pmap -> heap);
#ifdef DEBUG_PMAP
printf("Got %lu\n", pmap -> heapBufLen);
#endif
if (ferror(pmap -> heap))
error(SYSTEM, "failed to read photon heap in buildPhotonMap");
for (n = pmap -> heapBufLen, p = pmap -> heapBuf; n; n--, p++) {
/* Update min and max pos and set photon flux */
for (i = 0; i <= 2; i++) {
if (p -> pos [i] < pmap -> minPos [i])
pmap -> minPos [i] = p -> pos [i];
else if (p -> pos [i] > pmap -> maxPos [i])
pmap -> maxPos [i] = p -> pos [i];
/* Update centre of gravity with photon position */
CoG [i] += p -> pos [i];
}
if (primaryOfs)
/* Linearise photon primary index from subprocess index using the
* per-subprocess offsets in primaryOfs */
p -> primary += primaryOfs [p -> proc];
/* Scale photon's flux (hitherto normalised to 1 over RGB); in
* case of a contrib photon map, this is done per light source,
* and photonFlux is assumed to be an array */
getPhotonFlux(p, flux);
if (photonFlux) {
scalecolor(flux, photonFlux [isContribPmap(pmap) ?
photonSrcIdx(pmap, p) : 0]);
setPhotonFlux(p, flux);
}
/* Update average photon flux; need a double here */
addcolor(avgFlux, flux);
}
/* Write modified photons to new heap */
fwrite(pmap -> heapBuf, sizeof(Photon), pmap -> heapBufLen, nuHeap);
if (ferror(nuHeap))
error(SYSTEM, "failed postprocessing photon flux in "
"buildPhotonMap");
nCheck += pmap -> heapBufLen;
}
#ifdef DEBUG_PMAP
if (nCheck < pmap -> numPhotons)
error(INTERNAL, "truncated photon heap in buildPhotonMap");
#endif
/* Finalise average photon flux */
scalecolor(avgFlux, 1.0 / pmap -> numPhotons);
copycolor(pmap -> photonFlux, avgFlux);
/* Average photon positions to get centre of gravity */
for (i = 0; i < 3; i++)
pmap -> CoG [i] = CoG [i] /= pmap -> numPhotons;
rewind(pmap -> heap);
/* Compute average photon distance to centre of gravity */
while (!feof(pmap -> heap)) {
pmap -> heapBufLen = fread(pmap -> heapBuf, sizeof(Photon),
pmap -> heapBufSize, pmap -> heap);
for (n = pmap -> heapBufLen, p = pmap -> heapBuf; n; n--, p++) {
VSUB(d, p -> pos, CoG);
CoGdist += DOT(d, d);
}
}
pmap -> CoGdist = CoGdist /= pmap -> numPhotons;
/* Swap heaps, discarding unscaled photons */
fclose(pmap -> heap);
unlink(pmap -> heapFname);
pmap -> heap = nuHeap;
strcpy(pmap -> heapFname, nuHeapFname);
#ifdef PMAP_OOC
OOC_BuildPhotonMap(pmap, nproc);
#else
kdT_BuildPhotonMap(pmap);
#endif
/* Trash heap and its buffa */
free(pmap -> heapBuf);
fclose(pmap -> heap);
unlink(pmap -> heapFname);
pmap -> heap = NULL;
pmap -> heapBuf = NULL;
}
