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/* Copyright (c) 1991 Regents of the University of California */ |
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/* Copyright (c) 1993 Regents of the University of California */ |
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#ifndef lint |
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static char SCCSid[] = "$SunId$ LBL"; |
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#include "source.h" |
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|
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– |
#include "random.h" |
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– |
|
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/* |
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* Structures used by direct() |
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*/ |
| 24 |
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|
| 25 |
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typedef struct { |
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+ |
int sno; /* source number */ |
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FVECT dir; /* source direction */ |
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COLOR coef; /* material coefficient */ |
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COLOR val; /* contribution */ |
| 30 |
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} CONTRIB; /* direct contribution */ |
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|
| 32 |
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typedef struct { |
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< |
int sno; /* source number */ |
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> |
int sndx; /* source index (to CONTRIB array) */ |
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float brt; /* brightness (for comparison) */ |
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} CNTPTR; /* contribution pointer */ |
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|
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static CONTRIB *srccnt; /* source contributions in direct() */ |
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static CNTPTR *cntord; /* source ordering in direct() */ |
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+ |
static int maxcntr = 0; /* size of contribution arrays */ |
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|
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|
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marksources() /* find and mark source objects */ |
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{ |
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+ |
int foundsource = 0; |
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int i; |
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register OBJREC *o, *m; |
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register int ns; |
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if (m->otype == MAT_GLOW) { |
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source[ns].sflags |= SPROX; |
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source[ns].sl.prox = m->oargs.farg[3]; |
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< |
if (o->otype == OBJ_SOURCE) |
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> |
if (source[ns].sflags & SDISTANT) |
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source[ns].sflags |= SSKIP; |
| 86 |
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} else if (m->otype == MAT_SPOT) { |
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source[ns].sflags |= SSPOT; |
| 94 |
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source[ns].sflags |= SSKIP; |
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} |
| 96 |
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} |
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+ |
if (!(source[ns].sflags & SSKIP)) |
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+ |
foundsource++; |
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} |
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< |
if (nsources <= 0) { |
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> |
if (!foundsource) { |
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error(WARNING, "no light sources found"); |
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return; |
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} |
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markvirtuals(); /* find and add virtual sources */ |
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< |
srccnt = (CONTRIB *)malloc(nsources*sizeof(CONTRIB)); |
| 106 |
< |
cntord = (CNTPTR *)malloc(nsources*sizeof(CNTPTR)); |
| 107 |
< |
if (srccnt == NULL || cntord == NULL) |
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> |
/* allocate our contribution arrays */ |
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> |
maxcntr = nsources + MAXSPART; /* start with this many */ |
| 107 |
> |
srccnt = (CONTRIB *)malloc(maxcntr*sizeof(CONTRIB)); |
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> |
cntord = (CNTPTR *)malloc(maxcntr*sizeof(CNTPTR)); |
| 109 |
> |
if (srccnt == NULL | cntord == NULL) |
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goto memerr; |
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return; |
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memerr: |
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} |
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|
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< |
double |
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srcray(sr, r, sn) /* send a ray to a source, return domega */ |
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> |
srcray(sr, r, si) /* send a ray to a source, return domega */ |
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register RAY *sr; /* returned source ray */ |
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RAY *r; /* ray which hit object */ |
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< |
register int sn; /* source number */ |
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> |
SRCINDEX *si; /* source sample index */ |
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{ |
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< |
double ddot; /* (distance times) cosine */ |
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< |
FVECT vd; |
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< |
double d; |
| 121 |
< |
register int i; |
| 122 |
> |
double d; /* distance to source */ |
| 123 |
> |
register SRCREC *srcp; |
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|
| 125 |
< |
if (source[sn].sflags & SSKIP) |
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< |
return(0.0); /* skip this source */ |
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> |
rayorigin(sr, r, SHADOW, 1.0); /* ignore limits */ |
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|
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rayorigin(sr, r, SHADOW, 1.0); /* ignore limits */ |
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|
| 129 |
< |
sr->rsrc = sn; /* remember source */ |
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/* get source direction */ |
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if (source[sn].sflags & SDISTANT) { |
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/* constant direction */ |
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< |
VCOPY(sr->rdir, source[sn].sloc); |
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} else { /* compute direction */ |
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for (i = 0; i < 3; i++) |
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sr->rdir[i] = source[sn].sloc[i] - sr->rorg[i]; |
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< |
|
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< |
if (source[sn].sflags & SFLAT && |
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< |
(ddot = -DOT(sr->rdir, source[sn].snorm)) <= FTINY) |
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return(0.0); /* behind surface! */ |
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> |
while ((d = nextssamp(sr, si)) != 0.0) { |
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> |
sr->rsrc = si->sn; /* remember source */ |
| 129 |
> |
srcp = source + si->sn; |
| 130 |
> |
if (srcp->sflags & SDISTANT) { |
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> |
if (srcp->sflags & SSPOT && spotout(sr, srcp->sl.s, 1)) |
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> |
continue; |
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> |
return(1); /* sample OK */ |
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} |
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< |
if (dstrsrc > FTINY) { |
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< |
/* distribute source direction */ |
| 143 |
< |
dimlist[ndims] = sn + 8831; |
| 144 |
< |
peano(vd, 3, urand(ilhash(dimlist,ndims+1)+samplendx), .01); |
| 145 |
< |
for (i = 0; i < 3; i++) |
| 146 |
< |
vd[i] = dstrsrc * source[sn].ss * (1. - 2.*vd[i]); |
| 147 |
< |
if (source[sn].sflags & SFLAT) { /* project offset */ |
| 148 |
< |
d = DOT(vd, source[sn].snorm); |
| 149 |
< |
for (i = 0; i < 3; i++) |
| 150 |
< |
vd[i] -= d * source[sn].snorm[i]; |
| 151 |
< |
} |
| 152 |
< |
for (i = 0; i < 3; i++) /* offset source direction */ |
| 153 |
< |
sr->rdir[i] += vd[i]; |
| 154 |
< |
/* normalize */ |
| 155 |
< |
d = normalize(sr->rdir); |
| 156 |
< |
|
| 157 |
< |
} else if (!(source[sn].sflags & SDISTANT)) |
| 158 |
< |
/* normalize direction */ |
| 159 |
< |
d = normalize(sr->rdir); |
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< |
|
| 161 |
< |
if (source[sn].sflags & SDISTANT) { |
| 162 |
< |
if (source[sn].sflags & SSPOT) { /* check location */ |
| 163 |
< |
for (i = 0; i < 3; i++) |
| 164 |
< |
vd[i] = source[sn].sl.s->aim[i] - sr->rorg[i]; |
| 165 |
< |
d = DOT(sr->rdir,vd); |
| 166 |
< |
if (d <= FTINY) |
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< |
return(0.0); |
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< |
d = DOT(vd,vd) - d*d; |
| 169 |
< |
if (PI*d > source[sn].sl.s->siz) |
| 170 |
< |
return(0.0); |
| 171 |
< |
} |
| 172 |
< |
return(source[sn].ss2); /* domega constant */ |
| 173 |
< |
} |
| 174 |
< |
/* check direction */ |
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< |
if (d == 0.0) |
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< |
return(0.0); |
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> |
/* local source */ |
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/* check proximity */ |
| 137 |
< |
if (source[sn].sflags & SPROX && |
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< |
d > source[sn].sl.prox) |
| 180 |
< |
return(0.0); |
| 181 |
< |
/* compute dot product */ |
| 182 |
< |
if (source[sn].sflags & SFLAT) |
| 183 |
< |
ddot /= d; |
| 184 |
< |
else |
| 185 |
< |
ddot = 1.0; |
| 137 |
> |
if (srcp->sflags & SPROX && d > srcp->sl.prox) |
| 138 |
> |
continue; |
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/* check angle */ |
| 140 |
< |
if (source[sn].sflags & SSPOT) { |
| 141 |
< |
if (source[sn].sl.s->siz < 2.0*PI * |
| 142 |
< |
(1.0 + DOT(source[sn].sl.s->aim,sr->rdir))) |
| 143 |
< |
return(0.0); |
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< |
d += source[sn].sl.s->flen; /* adjust length */ |
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> |
if (srcp->sflags & SSPOT) { |
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> |
if (spotout(sr, srcp->sl.s, 0)) |
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> |
continue; |
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> |
/* adjust solid angle */ |
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> |
si->dom *= d*d; |
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> |
d += srcp->sl.s->flen; |
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> |
si->dom /= d*d; |
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} |
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< |
/* compute domega */ |
| 149 |
< |
return(ddot*source[sn].ss2/(d*d)); |
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> |
return(1); /* sample OK */ |
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> |
} |
| 150 |
> |
return(0); /* no more samples */ |
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} |
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|
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|
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srcvalue(r) /* punch ray to source and compute value */ |
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< |
RAY *r; |
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> |
register RAY *r; |
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{ |
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register SRCREC *sp; |
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|
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/* check intersection */ |
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if (!(*ofun[sp->so->otype].funp)(sp->so, r)) |
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return; |
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< |
raycont(r); /* compute contribution */ |
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> |
if (!rayshade(r, r->ro->omod)) /* compute contribution */ |
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> |
goto nomat; |
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return; |
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} |
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/* compute intersection */ |
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(*ofun[sp->so->otype].funp)(sp->so, r)) { |
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if (sp->sa.success >= 0) |
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sp->sa.success++; |
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< |
raycont(r); /* compute contribution */ |
| 173 |
> |
if (!rayshade(r, r->ro->omod)) /* compute contribution */ |
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> |
goto nomat; |
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return; |
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} |
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+ |
/* we missed our mark! */ |
| 178 |
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if (sp->sa.success < 0) |
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return; /* bitched already */ |
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sp->sa.success -= AIMREQT; |
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sprintf(errmsg, "aiming failure for light source \"%s\"", |
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sp->so->oname); |
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error(WARNING, errmsg); /* issue warning */ |
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+ |
return; |
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+ |
nomat: |
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+ |
objerror(r->ro, USER, "material not found"); |
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} |
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|
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|
| 192 |
+ |
sourcehit(r) /* check to see if ray hit distant source */ |
| 193 |
+ |
register RAY *r; |
| 194 |
+ |
{ |
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+ |
int first, last; |
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+ |
register int i; |
| 197 |
+ |
|
| 198 |
+ |
if (r->rsrc >= 0) { /* check only one if aimed */ |
| 199 |
+ |
first = last = r->rsrc; |
| 200 |
+ |
} else { /* otherwise check all */ |
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+ |
first = 0; last = nsources-1; |
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+ |
} |
| 203 |
+ |
for (i = first; i <= last; i++) |
| 204 |
+ |
if ((source[i].sflags & (SDISTANT|SVIRTUAL)) == SDISTANT) |
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+ |
/* |
| 206 |
+ |
* Check to see if ray is within |
| 207 |
+ |
* solid angle of source. |
| 208 |
+ |
*/ |
| 209 |
+ |
if (2.0*PI * (1.0 - DOT(source[i].sloc,r->rdir)) |
| 210 |
+ |
<= source[i].ss2) { |
| 211 |
+ |
r->ro = source[i].so; |
| 212 |
+ |
if (!(source[i].sflags & SSKIP)) |
| 213 |
+ |
break; |
| 214 |
+ |
} |
| 215 |
+ |
|
| 216 |
+ |
if (r->ro != NULL) { |
| 217 |
+ |
for (i = 0; i < 3; i++) |
| 218 |
+ |
r->ron[i] = -r->rdir[i]; |
| 219 |
+ |
r->rod = 1.0; |
| 220 |
+ |
r->rox = NULL; |
| 221 |
+ |
return(1); |
| 222 |
+ |
} |
| 223 |
+ |
return(0); |
| 224 |
+ |
} |
| 225 |
+ |
|
| 226 |
+ |
|
| 227 |
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static int |
| 228 |
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cntcmp(sc1, sc2) /* contribution compare (descending) */ |
| 229 |
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register CNTPTR *sc1, *sc2; |
| 242 |
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char *p; /* data for f */ |
| 243 |
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{ |
| 244 |
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extern int (*trace)(); |
| 248 |
– |
extern double pow(); |
| 245 |
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register int sn; |
| 246 |
+ |
register CONTRIB *scp; |
| 247 |
+ |
SRCINDEX si; |
| 248 |
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int nshadcheck, ncnts; |
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int nhits; |
| 250 |
< |
double dom, prob, ourthresh, hwt; |
| 250 |
> |
double prob, ourthresh, hwt; |
| 251 |
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RAY sr; |
| 252 |
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/* NOTE: srccnt and cntord global so no recursion */ |
| 253 |
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if (nsources <= 0) |
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return; /* no sources?! */ |
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– |
/* compute number to check */ |
| 258 |
– |
nshadcheck = pow((double)nsources, shadcert) + .5; |
| 259 |
– |
/* modify threshold */ |
| 260 |
– |
ourthresh = shadthresh / r->rweight; |
| 255 |
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/* potential contributions */ |
| 256 |
< |
for (sn = 0; sn < nsources; sn++) { |
| 257 |
< |
cntord[sn].sno = sn; |
| 258 |
< |
cntord[sn].brt = 0.0; |
| 259 |
< |
/* get source ray */ |
| 260 |
< |
if ((dom = srcray(&sr, r, sn)) == 0.0) |
| 261 |
< |
continue; |
| 262 |
< |
VCOPY(srccnt[sn].dir, sr.rdir); |
| 256 |
> |
initsrcindex(&si); |
| 257 |
> |
for (sn = 0; srcray(&sr, r, &si); sn++) { |
| 258 |
> |
if (sn >= maxcntr) { |
| 259 |
> |
maxcntr = sn + MAXSPART; |
| 260 |
> |
srccnt = (CONTRIB *)realloc((char *)srccnt, |
| 261 |
> |
maxcntr*sizeof(CONTRIB)); |
| 262 |
> |
cntord = (CNTPTR *)realloc((char *)cntord, |
| 263 |
> |
maxcntr*sizeof(CNTPTR)); |
| 264 |
> |
if (srccnt == NULL | cntord == NULL) |
| 265 |
> |
error(SYSTEM, "out of memory in direct"); |
| 266 |
> |
} |
| 267 |
> |
cntord[sn].sndx = sn; |
| 268 |
> |
scp = srccnt + sn; |
| 269 |
> |
scp->sno = sr.rsrc; |
| 270 |
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/* compute coefficient */ |
| 271 |
< |
(*f)(srccnt[sn].coef, p, srccnt[sn].dir, dom); |
| 272 |
< |
cntord[sn].brt = bright(srccnt[sn].coef); |
| 271 |
> |
(*f)(scp->coef, p, sr.rdir, si.dom); |
| 272 |
> |
cntord[sn].brt = bright(scp->coef); |
| 273 |
|
if (cntord[sn].brt <= 0.0) |
| 274 |
|
continue; |
| 275 |
+ |
VCOPY(scp->dir, sr.rdir); |
| 276 |
|
/* compute potential */ |
| 277 |
|
sr.revf = srcvalue; |
| 278 |
|
rayvalue(&sr); |
| 279 |
< |
copycolor(srccnt[sn].val, sr.rcol); |
| 280 |
< |
multcolor(srccnt[sn].val, srccnt[sn].coef); |
| 281 |
< |
cntord[sn].brt = bright(srccnt[sn].val); |
| 279 |
> |
copycolor(scp->val, sr.rcol); |
| 280 |
> |
multcolor(scp->val, scp->coef); |
| 281 |
> |
cntord[sn].brt = bright(scp->val); |
| 282 |
|
} |
| 283 |
|
/* sort contributions */ |
| 284 |
< |
qsort(cntord, nsources, sizeof(CNTPTR), cntcmp); |
| 284 |
> |
qsort(cntord, sn, sizeof(CNTPTR), cntcmp); |
| 285 |
|
{ /* find last */ |
| 286 |
|
register int l, m; |
| 287 |
|
|
| 288 |
< |
sn = 0; ncnts = l = nsources; |
| 288 |
> |
ncnts = l = sn; |
| 289 |
> |
sn = 0; |
| 290 |
|
while ((m = (sn + ncnts) >> 1) != l) { |
| 291 |
|
if (cntord[m].brt > 0.0) |
| 292 |
|
sn = m; |
| 295 |
|
l = m; |
| 296 |
|
} |
| 297 |
|
} |
| 298 |
+ |
if (ncnts == 0) |
| 299 |
+ |
return; /* no contributions! */ |
| 300 |
|
/* accumulate tail */ |
| 301 |
|
for (sn = ncnts-1; sn > 0; sn--) |
| 302 |
|
cntord[sn-1].brt += cntord[sn].brt; |
| 303 |
+ |
/* compute number to check */ |
| 304 |
+ |
nshadcheck = pow((double)ncnts, shadcert) + .5; |
| 305 |
+ |
/* modify threshold */ |
| 306 |
+ |
ourthresh = shadthresh / r->rweight; |
| 307 |
|
/* test for shadows */ |
| 308 |
< |
nhits = 0; |
| 309 |
< |
for (sn = 0; sn < ncnts; sn++) { |
| 308 |
> |
for (nhits = 0, hwt = 0.0, sn = 0; sn < ncnts; |
| 309 |
> |
hwt += (double)source[scp->sno].nhits / |
| 310 |
> |
(double)source[scp->sno].ntests, |
| 311 |
> |
sn++) { |
| 312 |
|
/* check threshold */ |
| 313 |
|
if ((sn+nshadcheck>=ncnts ? cntord[sn].brt : |
| 314 |
|
cntord[sn].brt-cntord[sn+nshadcheck].brt) |
| 315 |
|
< ourthresh*bright(r->rcol)) |
| 316 |
|
break; |
| 317 |
< |
/* get statistics */ |
| 307 |
< |
source[cntord[sn].sno].ntests++; |
| 317 |
> |
scp = srccnt + cntord[sn].sndx; |
| 318 |
|
/* test for hit */ |
| 319 |
|
rayorigin(&sr, r, SHADOW, 1.0); |
| 320 |
< |
VCOPY(sr.rdir, srccnt[cntord[sn].sno].dir); |
| 321 |
< |
sr.rsrc = cntord[sn].sno; |
| 320 |
> |
VCOPY(sr.rdir, scp->dir); |
| 321 |
> |
sr.rsrc = scp->sno; |
| 322 |
> |
source[scp->sno].ntests++; /* keep statistics */ |
| 323 |
|
if (localhit(&sr, &thescene) && |
| 324 |
< |
( sr.ro != source[cntord[sn].sno].so || |
| 325 |
< |
source[cntord[sn].sno].sflags & SFOLLOW )) { |
| 324 |
> |
( sr.ro != source[scp->sno].so || |
| 325 |
> |
source[scp->sno].sflags & SFOLLOW )) { |
| 326 |
|
/* follow entire path */ |
| 327 |
< |
raycont(&sr); |
| 327 |
> |
if (!raycont(&sr)) |
| 328 |
> |
objerror(sr.ro, USER, "material not found"); |
| 329 |
|
if (trace != NULL) |
| 330 |
|
(*trace)(&sr); /* trace execution */ |
| 331 |
|
if (bright(sr.rcol) <= FTINY) |
| 332 |
|
continue; /* missed! */ |
| 333 |
< |
copycolor(srccnt[cntord[sn].sno].val, sr.rcol); |
| 334 |
< |
multcolor(srccnt[cntord[sn].sno].val, |
| 323 |
< |
srccnt[cntord[sn].sno].coef); |
| 333 |
> |
copycolor(scp->val, sr.rcol); |
| 334 |
> |
multcolor(scp->val, scp->coef); |
| 335 |
|
} |
| 336 |
|
/* add contribution if hit */ |
| 337 |
< |
addcolor(r->rcol, srccnt[cntord[sn].sno].val); |
| 337 |
> |
addcolor(r->rcol, scp->val); |
| 338 |
|
nhits++; |
| 339 |
< |
source[cntord[sn].sno].nhits++; |
| 339 |
> |
source[scp->sno].nhits++; |
| 340 |
|
} |
| 341 |
< |
/* surface hit rate */ |
| 342 |
< |
if (sn > 0) |
| 343 |
< |
hwt = (double)nhits / (double)sn; |
| 341 |
> |
/* source hit rate */ |
| 342 |
> |
if (hwt > FTINY) |
| 343 |
> |
hwt = (double)nhits / hwt; |
| 344 |
|
else |
| 345 |
|
hwt = 0.5; |
| 346 |
|
#ifdef DEBUG |
| 347 |
< |
sprintf(errmsg, "%d tested, %d untested, %f hit rate\n", |
| 347 |
> |
sprintf(errmsg, "%d tested, %d untested, %f conditional hit rate\n", |
| 348 |
|
sn, ncnts-sn, hwt); |
| 349 |
|
eputs(errmsg); |
| 350 |
|
#endif |
| 351 |
|
/* add in untested sources */ |
| 352 |
|
for ( ; sn < ncnts; sn++) { |
| 353 |
< |
prob = hwt * (double)source[cntord[sn].sno].nhits / |
| 354 |
< |
(double)source[cntord[sn].sno].ntests; |
| 355 |
< |
scalecolor(srccnt[cntord[sn].sno].val, prob); |
| 356 |
< |
addcolor(r->rcol, srccnt[cntord[sn].sno].val); |
| 353 |
> |
scp = srccnt + cntord[sn].sndx; |
| 354 |
> |
prob = hwt * (double)source[scp->sno].nhits / |
| 355 |
> |
(double)source[scp->sno].ntests; |
| 356 |
> |
if (prob > 1.0) |
| 357 |
> |
prob = 1.0; |
| 358 |
> |
scalecolor(scp->val, prob); |
| 359 |
> |
addcolor(r->rcol, scp->val); |
| 360 |
|
} |
| 361 |
+ |
} |
| 362 |
+ |
|
| 363 |
+ |
|
| 364 |
+ |
/**************************************************************** |
| 365 |
+ |
* The following macros were separated from the m_light() routine |
| 366 |
+ |
* because they are very nasty and difficult to understand. |
| 367 |
+ |
*/ |
| 368 |
+ |
|
| 369 |
+ |
/* illumblock * |
| 370 |
+ |
* |
| 371 |
+ |
* We cannot allow an illum to pass to another illum, because that |
| 372 |
+ |
* would almost certainly constitute overcounting. |
| 373 |
+ |
* However, we do allow an illum to pass to another illum |
| 374 |
+ |
* that is actually going to relay to a virtual light source. |
| 375 |
+ |
* We also prevent an illum from passing to a glow; this provides a |
| 376 |
+ |
* convenient mechanism for defining detailed light source |
| 377 |
+ |
* geometry behind (or inside) an effective radiator. |
| 378 |
+ |
*/ |
| 379 |
+ |
|
| 380 |
+ |
static int weaksrcmod(obj) int obj; /* efficiency booster function */ |
| 381 |
+ |
{register OBJREC *o = objptr(obj); |
| 382 |
+ |
return(o->otype==MAT_ILLUM|o->otype==MAT_GLOW);} |
| 383 |
+ |
|
| 384 |
+ |
#define illumblock(m, r) (!(source[r->rsrc].sflags&SVIRTUAL) && \ |
| 385 |
+ |
r->rod > 0.0 && \ |
| 386 |
+ |
weaksrcmod(source[r->rsrc].so->omod)) |
| 387 |
+ |
|
| 388 |
+ |
/* wrongsource * |
| 389 |
+ |
* |
| 390 |
+ |
* This source is the wrong source (ie. overcounted) if we are |
| 391 |
+ |
* aimed to a different source than the one we hit and the one |
| 392 |
+ |
* we hit is not an illum that should be passed. |
| 393 |
+ |
*/ |
| 394 |
+ |
|
| 395 |
+ |
#define wrongsource(m, r) (r->rsrc>=0 && source[r->rsrc].so!=r->ro && \ |
| 396 |
+ |
(m->otype!=MAT_ILLUM || illumblock(m,r))) |
| 397 |
+ |
|
| 398 |
+ |
/* distglow * |
| 399 |
+ |
* |
| 400 |
+ |
* A distant glow is an object that sometimes acts as a light source, |
| 401 |
+ |
* but is too far away from the test point to be one in this case. |
| 402 |
+ |
* (Glows with negative radii should NEVER participate in illumination.) |
| 403 |
+ |
*/ |
| 404 |
+ |
|
| 405 |
+ |
#define distglow(m, r) (m->otype==MAT_GLOW && \ |
| 406 |
+ |
m->oargs.farg[3] >= -FTINY && \ |
| 407 |
+ |
r->rot > m->oargs.farg[3]) |
| 408 |
+ |
|
| 409 |
+ |
/* badcomponent * |
| 410 |
+ |
* |
| 411 |
+ |
* We must avoid counting light sources in the ambient calculation, |
| 412 |
+ |
* since the direct component is handled separately. Therefore, any |
| 413 |
+ |
* ambient ray which hits an active light source must be discarded. |
| 414 |
+ |
* The same is true for stray specular samples, since the specular |
| 415 |
+ |
* contribution from light sources is calculated separately. |
| 416 |
+ |
*/ |
| 417 |
+ |
|
| 418 |
+ |
#define badcomponent(m, r) (r->crtype&(AMBIENT|SPECULAR) && \ |
| 419 |
+ |
!(r->crtype&SHADOW || r->rod < 0.0 || \ |
| 420 |
+ |
distglow(m, r))) |
| 421 |
+ |
|
| 422 |
+ |
/* passillum * |
| 423 |
+ |
* |
| 424 |
+ |
* An illum passes to another material type when we didn't hit it |
| 425 |
+ |
* on purpose (as part of a direct calculation), or it is relaying |
| 426 |
+ |
* a virtual light source. |
| 427 |
+ |
*/ |
| 428 |
+ |
|
| 429 |
+ |
#define passillum(m, r) (m->otype==MAT_ILLUM && \ |
| 430 |
+ |
(r->rsrc<0 || source[r->rsrc].so!=r->ro || \ |
| 431 |
+ |
source[r->rsrc].sflags&SVIRTUAL)) |
| 432 |
+ |
|
| 433 |
+ |
/* srcignore * |
| 434 |
+ |
* |
| 435 |
+ |
* The -dv flag is normally on for sources to be visible. |
| 436 |
+ |
*/ |
| 437 |
+ |
|
| 438 |
+ |
#define srcignore(m, r) (!directvis && !(r->crtype&SHADOW) && \ |
| 439 |
+ |
!distglow(m, r)) |
| 440 |
+ |
|
| 441 |
+ |
|
| 442 |
+ |
m_light(m, r) /* ray hit a light source */ |
| 443 |
+ |
register OBJREC *m; |
| 444 |
+ |
register RAY *r; |
| 445 |
+ |
{ |
| 446 |
+ |
/* check for over-counting */ |
| 447 |
+ |
if (badcomponent(m, r)) |
| 448 |
+ |
return(1); |
| 449 |
+ |
if (wrongsource(m,r)) |
| 450 |
+ |
return(1); |
| 451 |
+ |
/* check for passed illum */ |
| 452 |
+ |
if (passillum(m, r)) { |
| 453 |
+ |
if (m->oargs.nsargs && strcmp(m->oargs.sarg[0], VOIDID)) |
| 454 |
+ |
return(rayshade(r, modifier(m->oargs.sarg[0]))); |
| 455 |
+ |
raytrans(r); |
| 456 |
+ |
return(1); |
| 457 |
+ |
} |
| 458 |
+ |
/* otherwise treat as source */ |
| 459 |
+ |
/* check for behind */ |
| 460 |
+ |
if (r->rod < 0.0) |
| 461 |
+ |
return(1); |
| 462 |
+ |
/* check for invisibility */ |
| 463 |
+ |
if (srcignore(m, r)) |
| 464 |
+ |
return(1); |
| 465 |
+ |
/* check for outside spot */ |
| 466 |
+ |
if (m->otype==MAT_SPOT && spotout(r, makespot(m), r->rot>=FHUGE)) |
| 467 |
+ |
return(1); |
| 468 |
+ |
/* get distribution pattern */ |
| 469 |
+ |
raytexture(r, m->omod); |
| 470 |
+ |
/* get source color */ |
| 471 |
+ |
setcolor(r->rcol, m->oargs.farg[0], |
| 472 |
+ |
m->oargs.farg[1], |
| 473 |
+ |
m->oargs.farg[2]); |
| 474 |
+ |
/* modify value */ |
| 475 |
+ |
multcolor(r->rcol, r->pcol); |
| 476 |
+ |
return(1); |
| 477 |
|
} |
