--- ray/src/rt/source.c 1992/08/28 14:07:41 2.4 +++ ray/src/rt/source.c 1995/12/09 11:30:19 2.20 @@ -1,4 +1,4 @@ -/* Copyright (c) 1992 Regents of the University of California */ +/* Copyright (c) 1995 Regents of the University of California */ #ifndef lint static char SCCSid[] = "$SunId$ LBL"; @@ -18,6 +18,10 @@ static char SCCSid[] = "$SunId$ LBL"; #include "source.h" +#include "random.h" + +extern double ssampdist; /* scatter sampling distance */ + /* * Structures used by direct() */ @@ -68,6 +72,9 @@ marksources() /* find and mark source objects */ o->otype != OBJ_SOURCE && m->oargs.farg[3] <= FTINY) continue; /* don't bother */ + if (m->oargs.farg[0] <= FTINY && m->oargs.farg[1] <= FTINY && + m->oargs.farg[2] <= FTINY) + continue; /* don't bother */ if (sfun[o->otype].of == NULL || sfun[o->otype].of->setsrc == NULL) @@ -81,7 +88,7 @@ marksources() /* find and mark source objects */ if (m->otype == MAT_GLOW) { source[ns].sflags |= SPROX; source[ns].sl.prox = m->oargs.farg[3]; - if (o->otype == OBJ_SOURCE) + if (source[ns].sflags & SDISTANT) source[ns].sflags |= SSKIP; } else if (m->otype == MAT_SPOT) { source[ns].sflags |= SSPOT; @@ -128,7 +135,7 @@ SRCINDEX *si; /* source sample index */ sr->rsrc = si->sn; /* remember source */ srcp = source + si->sn; if (srcp->sflags & SDISTANT) { - if (srcp->sflags & SSPOT && spotout(sr, srcp->sl.s, 1)) + if (srcp->sflags & SSPOT && spotout(sr, srcp->sl.s)) continue; return(1); /* sample OK */ } @@ -138,7 +145,7 @@ SRCINDEX *si; /* source sample index */ continue; /* check angle */ if (srcp->sflags & SSPOT) { - if (spotout(sr, srcp->sl.s, 0)) + if (spotout(sr, srcp->sl.s)) continue; /* adjust solid angle */ si->dom *= d*d; @@ -152,7 +159,7 @@ SRCINDEX *si; /* source sample index */ srcvalue(r) /* punch ray to source and compute value */ -RAY *r; +register RAY *r; { register SRCREC *sp; @@ -161,7 +168,9 @@ RAY *r; /* check intersection */ if (!(*ofun[sp->so->otype].funp)(sp->so, r)) return; - raycont(r); /* compute contribution */ + if (!rayshade(r, r->ro->omod)) /* compute contribution */ + goto nomat; + rayparticipate(r); return; } /* compute intersection */ @@ -169,9 +178,12 @@ RAY *r; (*ofun[sp->so->otype].funp)(sp->so, r)) { if (sp->sa.success >= 0) sp->sa.success++; - raycont(r); /* compute contribution */ + if (!rayshade(r, r->ro->omod)) /* compute contribution */ + goto nomat; + rayparticipate(r); return; } + /* we missed our mark! */ if (sp->sa.success < 0) return; /* bitched already */ sp->sa.success -= AIMREQT; @@ -180,9 +192,47 @@ RAY *r; sprintf(errmsg, "aiming failure for light source \"%s\"", sp->so->oname); error(WARNING, errmsg); /* issue warning */ + return; +nomat: + objerror(r->ro, USER, "material not found"); } +sourcehit(r) /* check to see if ray hit distant source */ +register RAY *r; +{ + int first, last; + register int i; + + if (r->rsrc >= 0) { /* check only one if aimed */ + first = last = r->rsrc; + } else { /* otherwise check all */ + first = 0; last = nsources-1; + } + for (i = first; i <= last; i++) + if ((source[i].sflags & (SDISTANT|SVIRTUAL)) == SDISTANT) + /* + * Check to see if ray is within + * solid angle of source. + */ + if (2.0*PI * (1.0 - DOT(source[i].sloc,r->rdir)) + <= source[i].ss2) { + r->ro = source[i].so; + if (!(source[i].sflags & SSKIP)) + break; + } + + if (r->ro != NULL) { + for (i = 0; i < 3; i++) + r->ron[i] = -r->rdir[i]; + r->rod = 1.0; + r->rox = NULL; + return(1); + } + return(0); +} + + static int cntcmp(sc1, sc2) /* contribution compare (descending) */ register CNTPTR *sc1, *sc2; @@ -201,8 +251,8 @@ int (*f)(); /* direct component coefficient functio char *p; /* data for f */ { extern int (*trace)(); - extern double pow(); register int sn; + register CONTRIB *scp; SRCINDEX si; int nshadcheck, ncnts; int nhits; @@ -224,19 +274,20 @@ char *p; /* data for f */ error(SYSTEM, "out of memory in direct"); } cntord[sn].sndx = sn; - srccnt[sn].sno = sr.rsrc; + scp = srccnt + sn; + scp->sno = sr.rsrc; /* compute coefficient */ - (*f)(srccnt[sn].coef, p, sr.rdir, si.dom); - cntord[sn].brt = bright(srccnt[sn].coef); + (*f)(scp->coef, p, sr.rdir, si.dom); + cntord[sn].brt = bright(scp->coef); if (cntord[sn].brt <= 0.0) continue; - VCOPY(srccnt[sn].dir, sr.rdir); + VCOPY(scp->dir, sr.rdir); /* compute potential */ sr.revf = srcvalue; rayvalue(&sr); - copycolor(srccnt[sn].val, sr.rcol); - multcolor(srccnt[sn].val, srccnt[sn].coef); - cntord[sn].brt = bright(srccnt[sn].val); + copycolor(scp->val, sr.rcol); + multcolor(scp->val, scp->coef); + cntord[sn].brt = bright(scp->val); } /* sort contributions */ qsort(cntord, sn, sizeof(CNTPTR), cntcmp); @@ -263,91 +314,181 @@ char *p; /* data for f */ /* modify threshold */ ourthresh = shadthresh / r->rweight; /* test for shadows */ - nhits = 0; - for (sn = 0; sn < ncnts; sn++) { + 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, r, SHADOW, 1.0); - VCOPY(sr.rdir, srccnt[cntord[sn].sndx].dir); - sr.rsrc = srccnt[cntord[sn].sndx].sno; - source[sr.rsrc].ntests++; /* keep statistics */ + VCOPY(sr.rdir, scp->dir); + sr.rsrc = scp->sno; + source[scp->sno].ntests++; /* keep statistics */ if (localhit(&sr, &thescene) && - ( sr.ro != source[sr.rsrc].so || - source[sr.rsrc].sflags & SFOLLOW )) { + ( sr.ro != source[scp->sno].so || + source[scp->sno].sflags & SFOLLOW )) { /* follow entire path */ - raycont(&sr); + if (!raycont(&sr)) + objerror(sr.ro, USER, "material not found"); + rayparticipate(&sr); if (trace != NULL) (*trace)(&sr); /* trace execution */ if (bright(sr.rcol) <= FTINY) continue; /* missed! */ - copycolor(srccnt[cntord[sn].sndx].val, sr.rcol); - multcolor(srccnt[cntord[sn].sndx].val, - srccnt[cntord[sn].sndx].coef); + copycolor(scp->val, sr.rcol); + multcolor(scp->val, scp->coef); } /* add contribution if hit */ - addcolor(r->rcol, srccnt[cntord[sn].sndx].val); + addcolor(r->rcol, scp->val); nhits++; - source[sr.rsrc].nhits++; + source[scp->sno].nhits++; } - /* surface hit rate */ - if (sn > 0) - hwt = (double)nhits / (double)sn; + /* source hit rate */ + if (hwt > FTINY) + hwt = (double)nhits / hwt; else hwt = 0.5; #ifdef DEBUG - sprintf(errmsg, "%d tested, %d untested, %f hit rate\n", + sprintf(errmsg, "%d tested, %d untested, %f conditional hit rate\n", sn, ncnts-sn, hwt); eputs(errmsg); #endif /* add in untested sources */ for ( ; sn < ncnts; sn++) { - sr.rsrc = srccnt[cntord[sn].sndx].sno; - prob = hwt * (double)source[sr.rsrc].nhits / - (double)source[sr.rsrc].ntests; - scalecolor(srccnt[cntord[sn].sndx].val, prob); - addcolor(r->rcol, srccnt[cntord[sn].sndx].val); + scp = srccnt + cntord[sn].sndx; + prob = hwt * (double)source[scp->sno].nhits / + (double)source[scp->sno].ntests; + if (prob > 1.0) + prob = 1.0; + scalecolor(scp->val, prob); + addcolor(r->rcol, scp->val); } } +srcscatter(r) /* compute source scattering into ray */ +register RAY *r; +{ + int oldsampndx; + int nsamps; + RAY sr; + SRCINDEX si; + double t, lastt, d; + COLOR cumval, ctmp; + int i, j; + + if (r->slights == NULL || r->slights[0] == 0 || r->gecc >= 1.-FTINY) + return; + if (ssampdist <= FTINY || (nsamps = r->rot/ssampdist + .5) < 1) + nsamps = 1; + oldsampndx = samplendx; + samplendx = random()&0x7fff; /* randomize */ + initsrcindex(&si); + for (i = r->slights[0]; i > 0; i--) { /* for each source */ + setcolor(cumval, 0., 0., 0.); + lastt = r->rot; + for (j = nsamps; j-- > 0; ) { /* for each sample position */ + samplendx++; + t = r->rot * (j+frandom())/nsamps; + sr.rorg[0] = r->rorg[0] + r->rdir[0]*t; + sr.rorg[1] = r->rorg[1] + r->rdir[1]*t; + sr.rorg[2] = r->rorg[2] + r->rdir[2]*t; + sr.rmax = 0.; + /* sample ray to this source */ + if (si.sp >= si.np-1 || !srcray(&sr, NULL, &si) || + sr.rsrc != r->slights[i]) { + si.sn = r->slights[i]-1; /* reset */ + si.np = 0; + if (!srcray(&sr, NULL, &si) || + sr.rsrc != r->slights[i]) + continue; /* no path */ + } + copycolor(sr.cext, r->cext); + sr.albedo = r->albedo; + sr.gecc = r->gecc; + rayvalue(&sr); /* eval. source ray */ + if (bright(sr.rcol) <= FTINY) + continue; + /* compute fall-off */ + d = lastt - t; + setcolor(ctmp, 1.-d*colval(r->cext,RED), + 1.-d*colval(r->cext,GRN), + 1.-d*colval(r->cext,BLU)); + multcolor(cumval, ctmp); + lastt = t; + if (r->gecc <= FTINY) /* compute P(theta) */ + d = 1.; + else { + d = DOT(r->rdir, sr.rdir); + d = sqrt(1. + r->gecc*r->gecc - 2.*r->gecc*d); + d = (1. - r->gecc*r->gecc) / (d*d*d); + } + /* other factors */ + d *= si.dom * r->albedo * r->rot / (4.*PI*nsamps); + multcolor(sr.rcol, r->cext); + scalecolor(sr.rcol, d); + addcolor(cumval, sr.rcol); + } + /* final fall-off */ + setcolor(ctmp, 1.-lastt*colval(r->cext,RED), + 1.-lastt*colval(r->cext,GRN), + 1.-lastt*colval(r->cext,BLU)); + multcolor(cumval, ctmp); + addcolor(r->rcol, cumval); /* sum into ray result */ + } + samplendx = oldsampndx; +} + + /**************************************************************** * The following macros were separated from the m_light() routine * because they are very nasty and difficult to understand. */ -/* wrongillum * +/* illumblock * * * We cannot allow an illum to pass to another illum, because that * would almost certainly constitute overcounting. * However, we do allow an illum to pass to another illum * that is actually going to relay to a virtual light source. + * We also prevent an illum from passing to a glow; this provides a + * convenient mechanism for defining detailed light source + * geometry behind (or inside) an effective radiator. */ -#define wrongillum(m, r) (!(source[r->rsrc].sflags&SVIRTUAL) && \ - objptr(source[r->rsrc].so->omod)->otype==MAT_ILLUM) +static int weaksrcmod(obj) int obj; /* efficiency booster function */ +{register OBJREC *o = objptr(obj); +return(o->otype==MAT_ILLUM|o->otype==MAT_GLOW);} +#define illumblock(m, r) (!(source[r->rsrc].sflags&SVIRTUAL) && \ + r->rod > 0.0 && \ + weaksrcmod(source[r->rsrc].so->omod)) + /* wrongsource * * * This source is the wrong source (ie. overcounted) if we are * aimed to a different source than the one we hit and the one - * we hit is not an illum which should be passed. + * we hit is not an illum that should be passed. */ #define wrongsource(m, r) (r->rsrc>=0 && source[r->rsrc].so!=r->ro && \ - (m->otype!=MAT_ILLUM || wrongillum(m,r))) + (m->otype!=MAT_ILLUM || illumblock(m,r))) /* distglow * * * A distant glow is an object that sometimes acts as a light source, * but is too far away from the test point to be one in this case. + * (Glows with negative radii should NEVER participate in illumination.) */ -#define distglow(m, r) (m->otype==MAT_GLOW && \ - r->rot > m->oargs.farg[3]) +#define distglow(m, r, d) (m->otype==MAT_GLOW && \ + m->oargs.farg[3] >= -FTINY && \ + d > m->oargs.farg[3]) /* badcomponent * * @@ -360,15 +501,8 @@ char *p; /* data for f */ #define badcomponent(m, r) (r->crtype&(AMBIENT|SPECULAR) && \ !(r->crtype&SHADOW || r->rod < 0.0 || \ - distglow(m, r))) + /* not 100% correct */ distglow(m, r, r->rot))) -/* overcount * - * - * All overcounting possibilities are contained here. - */ - -#define overcount(m, r) (badcomponent(m,r) || wrongsource(m,r)) - /* passillum * * * An illum passes to another material type when we didn't hit it @@ -382,11 +516,11 @@ char *p; /* data for f */ /* srcignore * * - * The -di flag renders light sources invisible, and here is the test. + * The -dv flag is normally on for sources to be visible. */ -#define srcignore(m, r) (directinvis && !(r->crtype&SHADOW) && \ - !distglow(m, r)) +#define srcignore(m, r) !(directvis || r->crtype&SHADOW || \ + distglow(m, r, raydist(r,PRIMARY))) m_light(m, r) /* ray hit a light source */ @@ -394,26 +528,27 @@ register OBJREC *m; register RAY *r; { /* check for over-counting */ - if (overcount(m, r)) - return; + if (badcomponent(m, r)) + return(1); + if (wrongsource(m, r)) + return(1); /* check for passed illum */ if (passillum(m, r)) { - if (m->oargs.nsargs < 1 || !strcmp(m->oargs.sarg[0], VOIDID)) - raytrans(r); - else - rayshade(r, modifier(m->oargs.sarg[0])); - return; + if (m->oargs.nsargs && strcmp(m->oargs.sarg[0], VOIDID)) + return(rayshade(r, modifier(m->oargs.sarg[0]))); + raytrans(r); + return(1); } /* otherwise treat as source */ /* check for behind */ if (r->rod < 0.0) - return; + return(1); /* check for invisibility */ if (srcignore(m, r)) - return; + return(1); /* check for outside spot */ - if (m->otype==MAT_SPOT && spotout(r, (SPOT *)m->os, r->rot>=FHUGE)) - return; + if (m->otype==MAT_SPOT && spotout(r, makespot(m))) + return(1); /* get distribution pattern */ raytexture(r, m->omod); /* get source color */ @@ -422,4 +557,5 @@ register RAY *r; m->oargs.farg[2]); /* modify value */ multcolor(r->rcol, r->pcol); + return(1); }