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#ifndef lint
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static const char RCSid[] = "$Id: mkillum2.c,v 2.33 2009/09/08 23:05:47 greg Exp $";
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#endif
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/*
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* Routines to do the actual calculation for mkillum
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*/
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#include <string.h>
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#include "mkillum.h"
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#include "face.h"
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#include "cone.h"
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#include "source.h"
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#ifndef NBSDFSAMPS
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#define NBSDFSAMPS 256 /* BSDF resampling count */
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#endif
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| 19 |
COLORV * distarr = NULL; /* distribution array */
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int distsiz = 0;
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COLORV * direct_discount = NULL; /* amount to take off direct */
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void
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newdist( /* allocate & clear distribution array */
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int siz
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)
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{
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if (siz <= 0) {
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if (distsiz > 0)
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free((void *)distarr);
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distarr = NULL;
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distsiz = 0;
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return;
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}
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if (distsiz < siz) {
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if (distsiz > 0)
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free((void *)distarr);
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distarr = (COLORV *)malloc(sizeof(COLOR)*siz);
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if (distarr == NULL)
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error(SYSTEM, "out of memory in newdist");
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distsiz = siz;
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}
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memset(distarr, '\0', sizeof(COLOR)*siz);
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}
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static void
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new_discount() /* allocate space for direct contrib. record */
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{
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if (distsiz <= 0)
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return;
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direct_discount = (COLORV *)calloc(distsiz, sizeof(COLOR));
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if (direct_discount == NULL)
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error(SYSTEM, "out of memory in new_discount");
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}
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static void
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done_discount() /* clear off direct contrib. record */
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{
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if (direct_discount == NULL)
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return;
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free((void *)direct_discount);
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direct_discount = NULL;
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}
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int
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process_ray( /* process a ray result or report error */
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RAY *r,
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int rv
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)
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{
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COLORV *colp;
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if (rv == 0) /* no result ready */
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return(0);
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if (rv < 0)
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error(USER, "ray tracing process died");
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if (r->rno >= distsiz)
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error(INTERNAL, "bad returned index in process_ray");
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multcolor(r->rcol, r->rcoef); /* in case it's a source ray */
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colp = &distarr[r->rno * 3];
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addcolor(colp, r->rcol);
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if (r->rsrc >= 0 && /* remember source contrib. */
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direct_discount != NULL) {
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colp = &direct_discount[r->rno * 3];
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addcolor(colp, r->rcol);
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}
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return(1);
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}
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void
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raysamp( /* queue a ray sample */
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int ndx,
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FVECT org,
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FVECT dir
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)
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{
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RAY myRay;
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int rv;
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if ((ndx < 0) | (ndx >= distsiz))
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error(INTERNAL, "bad index in raysamp");
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VCOPY(myRay.rorg, org);
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VCOPY(myRay.rdir, dir);
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myRay.rmax = .0;
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rayorigin(&myRay, PRIMARY, NULL, NULL);
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myRay.rno = ndx;
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/* queue ray, check result */
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process_ray(&myRay, ray_pqueue(&myRay));
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}
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void
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srcsamps( /* sample sources from this surface position */
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struct illum_args *il,
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FVECT org,
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FVECT nrm,
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MAT4 ixfm
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)
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{
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int nalt, nazi;
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SRCINDEX si;
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RAY sr;
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FVECT v;
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double d;
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int i, j;
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/* get sampling density */
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if (il->sampdens <= 0) {
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nalt = nazi = 1;
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} else {
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i = PI * il->sampdens;
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nalt = sqrt(i/PI) + .5;
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nazi = PI*nalt + .5;
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}
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initsrcindex(&si); /* loop over (sub)sources */
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for ( ; ; ) {
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VCOPY(sr.rorg, org); /* pick side to shoot from */
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if (il->sd != NULL) {
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int sn = si.sn;
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if (si.sp+1 >= si.np) ++sn;
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if (sn >= nsources) break;
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if (source[sn].sflags & SDISTANT)
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d = DOT(source[sn].sloc, nrm);
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else {
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VSUB(v, source[sn].sloc, org);
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d = DOT(v, nrm);
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}
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} else
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d = 1.0; /* only transmission */
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if (d < 0.0)
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d = -1.0001*il->thick - 5.*FTINY;
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else
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d = 5.*FTINY;
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for (i = 3; i--; )
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sr.rorg[i] += d*nrm[i];
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samplendx++; /* increment sample counter */
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if (!srcray(&sr, NULL, &si))
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break; /* end of sources */
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/* index direction */
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if (ixfm != NULL)
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multv3(v, sr.rdir, ixfm);
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else
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VCOPY(v, sr.rdir);
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if (il->sd != NULL) {
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i = getBSDF_incndx(il->sd, v);
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if (i < 0)
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continue; /* must not be important */
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sr.rno = i;
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d = 1.0/getBSDF_incohm(il->sd, i);
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} else {
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if (v[2] >= -FTINY)
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continue; /* only sample transmission */
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v[0] = -v[0]; v[1] = -v[1]; v[2] = -v[2];
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sr.rno = flatindex(v, nalt, nazi);
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d = nalt*nazi*(1./PI) * v[2];
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}
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d *= si.dom; /* solid angle correction */
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scalecolor(sr.rcoef, d);
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process_ray(&sr, ray_pqueue(&sr));
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}
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}
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void
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rayclean() /* finish all pending rays */
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{
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RAY myRay;
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while (process_ray(&myRay, ray_presult(&myRay, 0)))
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;
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}
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static void
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mkaxes( /* compute u and v to go with n */
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FVECT u,
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FVECT v,
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FVECT n
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)
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{
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register int i;
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v[0] = v[1] = v[2] = 0.0;
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for (i = 0; i < 3; i++)
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if (n[i] < 0.6 && n[i] > -0.6)
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break;
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v[i] = 1.0;
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fcross(u, v, n);
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normalize(u);
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fcross(v, n, u);
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}
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static void
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rounddir( /* compute uniform spherical direction */
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register FVECT dv,
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double alt,
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double azi
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)
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{
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double d1, d2;
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dv[2] = 1. - 2.*alt;
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d1 = sqrt(1. - dv[2]*dv[2]);
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d2 = 2.*PI * azi;
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dv[0] = d1*cos(d2);
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dv[1] = d1*sin(d2);
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}
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void
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flatdir( /* compute uniform hemispherical direction */
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FVECT dv,
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double alt,
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double azi
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)
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{
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double d1, d2;
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d1 = sqrt(alt);
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d2 = 2.*PI * azi;
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dv[0] = d1*cos(d2);
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dv[1] = d1*sin(d2);
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dv[2] = sqrt(1. - alt);
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}
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int
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flatindex( /* compute index for hemispherical direction */
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FVECT dv,
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int nalt,
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int nazi
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)
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{
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double d;
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int i, j;
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d = 1.0 - dv[2]*dv[2];
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i = d*nalt;
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d = atan2(dv[1], dv[0]) * (0.5/PI);
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if (d < 0.0) d += 1.0;
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j = d*nazi + 0.5;
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if (j >= nazi) j = 0;
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return(i*nazi + j);
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}
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int
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my_default( /* default illum action */
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OBJREC *ob,
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struct illum_args *il,
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char *nm
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)
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{
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sprintf(errmsg, "(%s): cannot make illum for %s \"%s\"",
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nm, ofun[ob->otype].funame, ob->oname);
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error(WARNING, errmsg);
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printobj(il->altmat, ob);
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return(1);
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}
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int
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my_face( /* make an illum face */
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OBJREC *ob,
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struct illum_args *il,
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char *nm
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)
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{
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| 293 |
int dim[2];
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int n, nalt, nazi, alti;
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double sp[2], r1, r2;
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int h;
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FVECT dn, org, dir;
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FVECT u, v;
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| 299 |
double ur[2], vr[2];
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MAT4 xfm;
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| 301 |
int nallow;
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FACE *fa;
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int i, j;
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| 304 |
/* get/check arguments */
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| 305 |
fa = getface(ob);
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| 306 |
if (fa->area == 0.0) {
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freeface(ob);
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return(my_default(ob, il, nm));
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}
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/* set up sampling */
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| 311 |
if (il->sd != NULL) {
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if (!getBSDF_xfm(xfm, fa->norm, il->udir)) {
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objerror(ob, WARNING, "illegal up direction");
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freeface(ob);
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return(my_default(ob, il, nm));
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}
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n = il->sd->ninc;
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} else {
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| 319 |
if (il->sampdens <= 0) {
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nalt = nazi = 1; /* diffuse assumption */
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} else {
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n = PI * il->sampdens;
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nalt = sqrt(n/PI) + .5;
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nazi = PI*nalt + .5;
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}
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n = nazi*nalt;
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}
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newdist(n);
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/* take first edge >= sqrt(area) */
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for (j = fa->nv-1, i = 0; i < fa->nv; j = i++) {
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u[0] = VERTEX(fa,i)[0] - VERTEX(fa,j)[0];
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u[1] = VERTEX(fa,i)[1] - VERTEX(fa,j)[1];
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u[2] = VERTEX(fa,i)[2] - VERTEX(fa,j)[2];
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| 334 |
if ((r1 = DOT(u,u)) >= fa->area-FTINY)
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break;
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| 336 |
}
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| 337 |
if (i < fa->nv) { /* got one! -- let's align our axes */
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| 338 |
r2 = 1.0/sqrt(r1);
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u[0] *= r2; u[1] *= r2; u[2] *= r2;
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| 340 |
fcross(v, fa->norm, u);
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| 341 |
} else /* oh well, we'll just have to wing it */
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| 342 |
mkaxes(u, v, fa->norm);
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| 343 |
/* now, find limits in (u,v) coordinates */
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| 344 |
ur[0] = vr[0] = FHUGE;
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| 345 |
ur[1] = vr[1] = -FHUGE;
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| 346 |
for (i = 0; i < fa->nv; i++) {
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| 347 |
r1 = DOT(VERTEX(fa,i),u);
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| 348 |
if (r1 < ur[0]) ur[0] = r1;
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| 349 |
if (r1 > ur[1]) ur[1] = r1;
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| 350 |
r2 = DOT(VERTEX(fa,i),v);
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| 351 |
if (r2 < vr[0]) vr[0] = r2;
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| 352 |
if (r2 > vr[1]) vr[1] = r2;
|
| 353 |
}
|
| 354 |
dim[0] = random();
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| 355 |
/* sample polygon */
|
| 356 |
nallow = 5*n*il->nsamps;
|
| 357 |
for (dim[1] = 0; dim[1] < n; dim[1]++)
|
| 358 |
for (i = 0; i < il->nsamps; i++) {
|
| 359 |
/* randomize direction */
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| 360 |
h = ilhash(dim, 2) + i;
|
| 361 |
if (il->sd != NULL) {
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| 362 |
r_BSDF_incvec(dir, il->sd, dim[1], urand(h), xfm);
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| 363 |
} else {
|
| 364 |
multisamp(sp, 2, urand(h));
|
| 365 |
alti = dim[1]/nazi;
|
| 366 |
r1 = (alti + sp[0])/nalt;
|
| 367 |
r2 = (dim[1] - alti*nazi + sp[1] - .5)/nazi;
|
| 368 |
flatdir(dn, r1, r2);
|
| 369 |
for (j = 0; j < 3; j++)
|
| 370 |
dir[j] = -dn[0]*u[j] - dn[1]*v[j] -
|
| 371 |
dn[2]*fa->norm[j];
|
| 372 |
}
|
| 373 |
/* randomize location */
|
| 374 |
do {
|
| 375 |
multisamp(sp, 2, urand(h+4862+nallow));
|
| 376 |
r1 = ur[0] + (ur[1]-ur[0]) * sp[0];
|
| 377 |
r2 = vr[0] + (vr[1]-vr[0]) * sp[1];
|
| 378 |
for (j = 0; j < 3; j++)
|
| 379 |
org[j] = r1*u[j] + r2*v[j]
|
| 380 |
+ fa->offset*fa->norm[j];
|
| 381 |
} while (!inface(org, fa) && nallow-- > 0);
|
| 382 |
if (nallow < 0) {
|
| 383 |
objerror(ob, WARNING, "bad aspect");
|
| 384 |
rayclean();
|
| 385 |
freeface(ob);
|
| 386 |
return(my_default(ob, il, nm));
|
| 387 |
}
|
| 388 |
if (il->sd != NULL && DOT(dir, fa->norm) < -FTINY)
|
| 389 |
r1 = -1.0001*il->thick - 5.*FTINY;
|
| 390 |
else
|
| 391 |
r1 = 5.*FTINY;
|
| 392 |
for (j = 0; j < 3; j++)
|
| 393 |
org[j] += r1*fa->norm[j];
|
| 394 |
/* send sample */
|
| 395 |
raysamp(dim[1], org, dir);
|
| 396 |
}
|
| 397 |
/* add in direct component? */
|
| 398 |
if (!directvis && (il->flags & IL_LIGHT || il->sd != NULL)) {
|
| 399 |
MAT4 ixfm;
|
| 400 |
if (il->sd == NULL) {
|
| 401 |
for (i = 3; i--; ) {
|
| 402 |
ixfm[i][0] = u[i];
|
| 403 |
ixfm[i][1] = v[i];
|
| 404 |
ixfm[i][2] = fa->norm[i];
|
| 405 |
ixfm[i][3] = 0.;
|
| 406 |
}
|
| 407 |
ixfm[3][0] = ixfm[3][1] = ixfm[3][2] = 0.;
|
| 408 |
ixfm[3][3] = 1.;
|
| 409 |
} else {
|
| 410 |
if (!invmat4(ixfm, xfm))
|
| 411 |
objerror(ob, INTERNAL,
|
| 412 |
"cannot invert BSDF transform");
|
| 413 |
if (!(il->flags & IL_LIGHT))
|
| 414 |
new_discount();
|
| 415 |
}
|
| 416 |
dim[0] = random();
|
| 417 |
nallow = 10*il->nsamps;
|
| 418 |
for (i = 0; i < il->nsamps; i++) {
|
| 419 |
/* randomize location */
|
| 420 |
h = dim[0] + samplendx++;
|
| 421 |
do {
|
| 422 |
multisamp(sp, 2, urand(h+nallow));
|
| 423 |
r1 = ur[0] + (ur[1]-ur[0]) * sp[0];
|
| 424 |
r2 = vr[0] + (vr[1]-vr[0]) * sp[1];
|
| 425 |
for (j = 0; j < 3; j++)
|
| 426 |
org[j] = r1*u[j] + r2*v[j]
|
| 427 |
+ fa->offset*fa->norm[j];
|
| 428 |
} while (!inface(org, fa) && nallow-- > 0);
|
| 429 |
if (nallow < 0) {
|
| 430 |
objerror(ob, WARNING, "bad aspect");
|
| 431 |
rayclean();
|
| 432 |
freeface(ob);
|
| 433 |
return(my_default(ob, il, nm));
|
| 434 |
}
|
| 435 |
/* sample source rays */
|
| 436 |
srcsamps(il, org, fa->norm, ixfm);
|
| 437 |
}
|
| 438 |
}
|
| 439 |
/* wait for all rays to finish */
|
| 440 |
rayclean();
|
| 441 |
if (il->sd != NULL) { /* run distribution through BSDF */
|
| 442 |
nalt = sqrt(il->sd->nout/PI) + .5;
|
| 443 |
nazi = PI*nalt + .5;
|
| 444 |
redistribute(il->sd, nalt, nazi, u, v, fa->norm, xfm);
|
| 445 |
done_discount();
|
| 446 |
if (!il->sampdens)
|
| 447 |
il->sampdens = nalt*nazi/PI + .999;
|
| 448 |
}
|
| 449 |
/* write out the face and its distribution */
|
| 450 |
if (average(il, distarr, n)) {
|
| 451 |
if (il->sampdens > 0)
|
| 452 |
flatout(il, distarr, nalt, nazi, u, v, fa->norm);
|
| 453 |
illumout(il, ob);
|
| 454 |
} else
|
| 455 |
printobj(il->altmat, ob);
|
| 456 |
/* clean up */
|
| 457 |
freeface(ob);
|
| 458 |
return(0);
|
| 459 |
}
|
| 460 |
|
| 461 |
|
| 462 |
int
|
| 463 |
my_sphere( /* make an illum sphere */
|
| 464 |
register OBJREC *ob,
|
| 465 |
struct illum_args *il,
|
| 466 |
char *nm
|
| 467 |
)
|
| 468 |
{
|
| 469 |
int dim[3];
|
| 470 |
int n, nalt, nazi;
|
| 471 |
double sp[4], r1, r2, r3;
|
| 472 |
FVECT org, dir;
|
| 473 |
FVECT u, v;
|
| 474 |
register int i, j;
|
| 475 |
/* check arguments */
|
| 476 |
if (ob->oargs.nfargs != 4)
|
| 477 |
objerror(ob, USER, "bad # of arguments");
|
| 478 |
/* set up sampling */
|
| 479 |
if (il->sampdens <= 0)
|
| 480 |
nalt = nazi = 1;
|
| 481 |
else {
|
| 482 |
n = 4.*PI * il->sampdens;
|
| 483 |
nalt = sqrt(2./PI*n) + .5;
|
| 484 |
nazi = PI/2.*nalt + .5;
|
| 485 |
}
|
| 486 |
if (il->sd != NULL)
|
| 487 |
objerror(ob, WARNING, "BSDF ignored");
|
| 488 |
n = nalt*nazi;
|
| 489 |
newdist(n);
|
| 490 |
dim[0] = random();
|
| 491 |
/* sample sphere */
|
| 492 |
for (dim[1] = 0; dim[1] < nalt; dim[1]++)
|
| 493 |
for (dim[2] = 0; dim[2] < nazi; dim[2]++)
|
| 494 |
for (i = 0; i < il->nsamps; i++) {
|
| 495 |
/* next sample point */
|
| 496 |
multisamp(sp, 4, urand(ilhash(dim,3)+i));
|
| 497 |
/* random direction */
|
| 498 |
r1 = (dim[1] + sp[0])/nalt;
|
| 499 |
r2 = (dim[2] + sp[1] - .5)/nazi;
|
| 500 |
rounddir(dir, r1, r2);
|
| 501 |
/* random location */
|
| 502 |
mkaxes(u, v, dir); /* yuck! */
|
| 503 |
r3 = sqrt(sp[2]);
|
| 504 |
r2 = 2.*PI*sp[3];
|
| 505 |
r1 = r3*ob->oargs.farg[3]*cos(r2);
|
| 506 |
r2 = r3*ob->oargs.farg[3]*sin(r2);
|
| 507 |
r3 = ob->oargs.farg[3]*sqrt(1.01-r3*r3);
|
| 508 |
for (j = 0; j < 3; j++) {
|
| 509 |
org[j] = ob->oargs.farg[j] + r1*u[j] + r2*v[j] +
|
| 510 |
r3*dir[j];
|
| 511 |
dir[j] = -dir[j];
|
| 512 |
}
|
| 513 |
/* send sample */
|
| 514 |
raysamp(dim[1]*nazi+dim[2], org, dir);
|
| 515 |
}
|
| 516 |
/* wait for all rays to finish */
|
| 517 |
rayclean();
|
| 518 |
/* write out the sphere and its distribution */
|
| 519 |
if (average(il, distarr, n)) {
|
| 520 |
if (il->sampdens > 0)
|
| 521 |
roundout(il, distarr, nalt, nazi);
|
| 522 |
else
|
| 523 |
objerror(ob, WARNING, "diffuse distribution");
|
| 524 |
illumout(il, ob);
|
| 525 |
} else
|
| 526 |
printobj(il->altmat, ob);
|
| 527 |
/* clean up */
|
| 528 |
return(1);
|
| 529 |
}
|
| 530 |
|
| 531 |
|
| 532 |
int
|
| 533 |
my_ring( /* make an illum ring */
|
| 534 |
OBJREC *ob,
|
| 535 |
struct illum_args *il,
|
| 536 |
char *nm
|
| 537 |
)
|
| 538 |
{
|
| 539 |
int dim[2];
|
| 540 |
int n, nalt, nazi, alti;
|
| 541 |
double sp[2], r1, r2, r3;
|
| 542 |
int h;
|
| 543 |
FVECT dn, org, dir;
|
| 544 |
FVECT u, v;
|
| 545 |
MAT4 xfm;
|
| 546 |
CONE *co;
|
| 547 |
int i, j;
|
| 548 |
/* get/check arguments */
|
| 549 |
co = getcone(ob, 0);
|
| 550 |
/* set up sampling */
|
| 551 |
if (il->sd != NULL) {
|
| 552 |
if (!getBSDF_xfm(xfm, co->ad, il->udir)) {
|
| 553 |
objerror(ob, WARNING, "illegal up direction");
|
| 554 |
freecone(ob);
|
| 555 |
return(my_default(ob, il, nm));
|
| 556 |
}
|
| 557 |
n = il->sd->ninc;
|
| 558 |
} else {
|
| 559 |
if (il->sampdens <= 0) {
|
| 560 |
nalt = nazi = 1; /* diffuse assumption */
|
| 561 |
} else {
|
| 562 |
n = PI * il->sampdens;
|
| 563 |
nalt = sqrt(n/PI) + .5;
|
| 564 |
nazi = PI*nalt + .5;
|
| 565 |
}
|
| 566 |
n = nazi*nalt;
|
| 567 |
}
|
| 568 |
newdist(n);
|
| 569 |
mkaxes(u, v, co->ad);
|
| 570 |
dim[0] = random();
|
| 571 |
/* sample disk */
|
| 572 |
for (dim[1] = 0; dim[1] < n; dim[1]++)
|
| 573 |
for (i = 0; i < il->nsamps; i++) {
|
| 574 |
/* next sample point */
|
| 575 |
h = ilhash(dim,2) + i;
|
| 576 |
/* randomize direction */
|
| 577 |
if (il->sd != NULL) {
|
| 578 |
r_BSDF_incvec(dir, il->sd, dim[1], urand(h), xfm);
|
| 579 |
} else {
|
| 580 |
multisamp(sp, 2, urand(h));
|
| 581 |
alti = dim[1]/nazi;
|
| 582 |
r1 = (alti + sp[0])/nalt;
|
| 583 |
r2 = (dim[1] - alti*nazi + sp[1] - .5)/nazi;
|
| 584 |
flatdir(dn, r1, r2);
|
| 585 |
for (j = 0; j < 3; j++)
|
| 586 |
dir[j] = -dn[0]*u[j] - dn[1]*v[j] - dn[2]*co->ad[j];
|
| 587 |
}
|
| 588 |
/* randomize location */
|
| 589 |
multisamp(sp, 2, urand(h+8371));
|
| 590 |
r3 = sqrt(CO_R0(co)*CO_R0(co) +
|
| 591 |
sp[0]*(CO_R1(co)*CO_R1(co) - CO_R0(co)*CO_R0(co)));
|
| 592 |
r2 = 2.*PI*sp[1];
|
| 593 |
r1 = r3*cos(r2);
|
| 594 |
r2 = r3*sin(r2);
|
| 595 |
if (il->sd != NULL && DOT(dir, co->ad) < -FTINY)
|
| 596 |
r3 = -1.0001*il->thick - 5.*FTINY;
|
| 597 |
else
|
| 598 |
r3 = 5.*FTINY;
|
| 599 |
for (j = 0; j < 3; j++)
|
| 600 |
org[j] = CO_P0(co)[j] + r1*u[j] + r2*v[j] +
|
| 601 |
r3*co->ad[j];
|
| 602 |
/* send sample */
|
| 603 |
raysamp(dim[1], org, dir);
|
| 604 |
}
|
| 605 |
/* add in direct component? */
|
| 606 |
if (!directvis && (il->flags & IL_LIGHT || il->sd != NULL)) {
|
| 607 |
MAT4 ixfm;
|
| 608 |
if (il->sd == NULL) {
|
| 609 |
for (i = 3; i--; ) {
|
| 610 |
ixfm[i][0] = u[i];
|
| 611 |
ixfm[i][1] = v[i];
|
| 612 |
ixfm[i][2] = co->ad[i];
|
| 613 |
ixfm[i][3] = 0.;
|
| 614 |
}
|
| 615 |
ixfm[3][0] = ixfm[3][1] = ixfm[3][2] = 0.;
|
| 616 |
ixfm[3][3] = 1.;
|
| 617 |
} else {
|
| 618 |
if (!invmat4(ixfm, xfm))
|
| 619 |
objerror(ob, INTERNAL,
|
| 620 |
"cannot invert BSDF transform");
|
| 621 |
if (!(il->flags & IL_LIGHT))
|
| 622 |
new_discount();
|
| 623 |
}
|
| 624 |
dim[0] = random();
|
| 625 |
for (i = 0; i < il->nsamps; i++) {
|
| 626 |
/* randomize location */
|
| 627 |
h = dim[0] + samplendx++;
|
| 628 |
multisamp(sp, 2, urand(h));
|
| 629 |
r3 = sqrt(CO_R0(co)*CO_R0(co) +
|
| 630 |
sp[0]*(CO_R1(co)*CO_R1(co) - CO_R0(co)*CO_R0(co)));
|
| 631 |
r2 = 2.*PI*sp[1];
|
| 632 |
r1 = r3*cos(r2);
|
| 633 |
r2 = r3*sin(r2);
|
| 634 |
for (j = 0; j < 3; j++)
|
| 635 |
org[j] = CO_P0(co)[j] + r1*u[j] + r2*v[j];
|
| 636 |
/* sample source rays */
|
| 637 |
srcsamps(il, org, co->ad, ixfm);
|
| 638 |
}
|
| 639 |
}
|
| 640 |
/* wait for all rays to finish */
|
| 641 |
rayclean();
|
| 642 |
if (il->sd != NULL) { /* run distribution through BSDF */
|
| 643 |
nalt = sqrt(il->sd->nout/PI) + .5;
|
| 644 |
nazi = PI*nalt + .5;
|
| 645 |
redistribute(il->sd, nalt, nazi, u, v, co->ad, xfm);
|
| 646 |
done_discount();
|
| 647 |
if (!il->sampdens)
|
| 648 |
il->sampdens = nalt*nazi/PI + .999;
|
| 649 |
}
|
| 650 |
/* write out the ring and its distribution */
|
| 651 |
if (average(il, distarr, n)) {
|
| 652 |
if (il->sampdens > 0)
|
| 653 |
flatout(il, distarr, nalt, nazi, u, v, co->ad);
|
| 654 |
illumout(il, ob);
|
| 655 |
} else
|
| 656 |
printobj(il->altmat, ob);
|
| 657 |
/* clean up */
|
| 658 |
freecone(ob);
|
| 659 |
return(1);
|
| 660 |
}
|
| 661 |
|
| 662 |
|
| 663 |
void
|
| 664 |
redistribute( /* pass distarr ray sums through BSDF */
|
| 665 |
struct BSDF_data *b,
|
| 666 |
int nalt,
|
| 667 |
int nazi,
|
| 668 |
FVECT u,
|
| 669 |
FVECT v,
|
| 670 |
FVECT w,
|
| 671 |
MAT4 xm
|
| 672 |
)
|
| 673 |
{
|
| 674 |
int nout = 0;
|
| 675 |
MAT4 mymat, inmat;
|
| 676 |
COLORV *idist;
|
| 677 |
COLORV *cp;
|
| 678 |
FVECT dv;
|
| 679 |
double wt;
|
| 680 |
int i, j, k, c, o;
|
| 681 |
COLOR col, cinc;
|
| 682 |
/* copy incoming distribution */
|
| 683 |
if (b->ninc > distsiz)
|
| 684 |
error(INTERNAL, "error 1 in redistribute");
|
| 685 |
idist = (COLORV *)malloc(sizeof(COLOR)*b->ninc);
|
| 686 |
if (idist == NULL)
|
| 687 |
error(SYSTEM, "out of memory in redistribute");
|
| 688 |
memcpy(idist, distarr, sizeof(COLOR)*b->ninc);
|
| 689 |
/* compose direction transform */
|
| 690 |
for (i = 3; i--; ) {
|
| 691 |
mymat[i][0] = u[i];
|
| 692 |
mymat[i][1] = v[i];
|
| 693 |
mymat[i][2] = w[i];
|
| 694 |
mymat[i][3] = 0.;
|
| 695 |
}
|
| 696 |
mymat[3][0] = mymat[3][1] = mymat[3][2] = 0.;
|
| 697 |
mymat[3][3] = 1.;
|
| 698 |
if (xm != NULL)
|
| 699 |
multmat4(mymat, xm, mymat);
|
| 700 |
for (i = 3; i--; ) { /* make sure it's normalized */
|
| 701 |
wt = 1./sqrt( mymat[0][i]*mymat[0][i] +
|
| 702 |
mymat[1][i]*mymat[1][i] +
|
| 703 |
mymat[2][i]*mymat[2][i] );
|
| 704 |
for (j = 3; j--; )
|
| 705 |
mymat[j][i] *= wt;
|
| 706 |
}
|
| 707 |
if (!invmat4(inmat, mymat)) /* need inverse as well */
|
| 708 |
error(INTERNAL, "cannot invert BSDF transform");
|
| 709 |
newdist(nalt*nazi); /* resample distribution */
|
| 710 |
for (i = b->ninc; i--; ) {
|
| 711 |
int direct_out = -1;
|
| 712 |
COLOR cdir;
|
| 713 |
getBSDF_incvec(dv, b, i); /* compute incident irrad. */
|
| 714 |
multv3(dv, dv, mymat);
|
| 715 |
if (dv[2] < 0.0) {
|
| 716 |
dv[0] = -dv[0]; dv[1] = -dv[1]; dv[2] = -dv[2];
|
| 717 |
direct_out += (direct_discount != NULL);
|
| 718 |
}
|
| 719 |
wt = getBSDF_incohm(b, i);
|
| 720 |
wt *= dv[2]; /* solid_angle*cosine(theta) */
|
| 721 |
cp = &idist[3*i];
|
| 722 |
copycolor(cinc, cp);
|
| 723 |
scalecolor(cinc, wt);
|
| 724 |
if (!direct_out) { /* discount direct contr. */
|
| 725 |
cp = &direct_discount[3*i];
|
| 726 |
copycolor(cdir, cp);
|
| 727 |
scalecolor(cdir, -wt);
|
| 728 |
if (b->nout != b->ninc)
|
| 729 |
direct_out = flatindex(dv, nalt, nazi);
|
| 730 |
else
|
| 731 |
direct_out = i; /* assumes dist. mirroring */
|
| 732 |
}
|
| 733 |
for (k = nalt; k--; ) /* loop over distribution */
|
| 734 |
for (j = nazi; j--; ) {
|
| 735 |
int rstart = random();
|
| 736 |
for (c = NBSDFSAMPS; c--; ) {
|
| 737 |
double sp[2];
|
| 738 |
multisamp(sp, 2, urand(rstart+c));
|
| 739 |
flatdir(dv, (k + sp[0])/nalt,
|
| 740 |
(j + .5 - sp[1])/nazi);
|
| 741 |
multv3(dv, dv, inmat);
|
| 742 |
/* evaluate BSDF @ outgoing */
|
| 743 |
o = getBSDF_outndx(b, dv);
|
| 744 |
if (o < 0) {
|
| 745 |
nout++;
|
| 746 |
continue;
|
| 747 |
}
|
| 748 |
wt = BSDF_value(b, i, o) * (1./NBSDFSAMPS);
|
| 749 |
copycolor(col, cinc);
|
| 750 |
if (b->nout != b->ninc)
|
| 751 |
o = k*nazi + j;
|
| 752 |
if (o == direct_out)
|
| 753 |
addcolor(col, cdir); /* minus direct */
|
| 754 |
scalecolor(col, wt);
|
| 755 |
cp = &distarr[3*(k*nazi + j)];
|
| 756 |
addcolor(cp, col); /* sum into distribution */
|
| 757 |
}
|
| 758 |
}
|
| 759 |
}
|
| 760 |
free(idist); /* free temp space */
|
| 761 |
if (nout) {
|
| 762 |
sprintf(errmsg, "missing %.1f%% of BSDF directions",
|
| 763 |
100.*nout/(b->ninc*nalt*nazi*NBSDFSAMPS));
|
| 764 |
error(WARNING, errmsg);
|
| 765 |
}
|
| 766 |
}
|
