| 1 |
greg |
2.17 |
/* Copyright (c) 1995 Regents of the University of California */
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| 2 |
greg |
1.1 |
|
| 3 |
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#ifndef lint
|
| 4 |
|
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static char SCCSid[] = "$SunId$ LBL";
|
| 5 |
|
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#endif
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| 6 |
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|
| 7 |
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/*
|
| 8 |
|
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* source.c - routines dealing with illumination sources.
|
| 9 |
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*
|
| 10 |
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* 8/20/85
|
| 11 |
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*/
|
| 12 |
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|
| 13 |
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#include "ray.h"
|
| 14 |
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|
| 15 |
greg |
1.4 |
#include "octree.h"
|
| 16 |
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|
| 17 |
greg |
1.1 |
#include "otypes.h"
|
| 18 |
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|
| 19 |
greg |
1.35 |
#include "source.h"
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| 20 |
greg |
1.1 |
|
| 21 |
greg |
2.19 |
#include "random.h"
|
| 22 |
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|
|
| 23 |
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extern double ssampdist; /* scatter sampling distance */
|
| 24 |
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|
| 25 |
greg |
2.22 |
#ifndef MAXSSAMP
|
| 26 |
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#define MAXSSAMP 16 /* maximum samples per ray */
|
| 27 |
|
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#endif
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| 28 |
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|
| 29 |
greg |
1.35 |
/*
|
| 30 |
|
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* Structures used by direct()
|
| 31 |
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*/
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| 32 |
greg |
1.1 |
|
| 33 |
greg |
1.35 |
typedef struct {
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| 34 |
greg |
1.45 |
int sno; /* source number */
|
| 35 |
greg |
1.35 |
FVECT dir; /* source direction */
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| 36 |
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COLOR coef; /* material coefficient */
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| 37 |
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COLOR val; /* contribution */
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| 38 |
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} CONTRIB; /* direct contribution */
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| 39 |
greg |
1.1 |
|
| 40 |
greg |
1.35 |
typedef struct {
|
| 41 |
greg |
1.45 |
int sndx; /* source index (to CONTRIB array) */
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| 42 |
greg |
1.35 |
float brt; /* brightness (for comparison) */
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| 43 |
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} CNTPTR; /* contribution pointer */
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| 44 |
greg |
1.1 |
|
| 45 |
greg |
1.25 |
static CONTRIB *srccnt; /* source contributions in direct() */
|
| 46 |
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static CNTPTR *cntord; /* source ordering in direct() */
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| 47 |
greg |
1.45 |
static int maxcntr = 0; /* size of contribution arrays */
|
| 48 |
greg |
1.1 |
|
| 49 |
greg |
1.25 |
|
| 50 |
greg |
1.1 |
marksources() /* find and mark source objects */
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| 51 |
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{
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| 52 |
greg |
2.3 |
int foundsource = 0;
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| 53 |
greg |
1.33 |
int i;
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| 54 |
greg |
1.1 |
register OBJREC *o, *m;
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| 55 |
greg |
1.36 |
register int ns;
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| 56 |
greg |
1.35 |
/* initialize dispatch table */
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| 57 |
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initstypes();
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| 58 |
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/* find direct sources */
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| 59 |
greg |
1.1 |
for (i = 0; i < nobjects; i++) {
|
| 60 |
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| 61 |
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o = objptr(i);
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| 62 |
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| 63 |
greg |
1.35 |
if (!issurface(o->otype) || o->omod == OVOID)
|
| 64 |
greg |
1.1 |
continue;
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| 65 |
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|
| 66 |
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m = objptr(o->omod);
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| 67 |
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|
| 68 |
greg |
1.24 |
if (!islight(m->otype))
|
| 69 |
greg |
1.1 |
continue;
|
| 70 |
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|
|
| 71 |
greg |
1.6 |
if (m->oargs.nfargs != (m->otype == MAT_GLOW ? 4 :
|
| 72 |
|
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m->otype == MAT_SPOT ? 7 : 3))
|
| 73 |
greg |
1.1 |
objerror(m, USER, "bad # arguments");
|
| 74 |
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|
| 75 |
greg |
1.6 |
if (m->otype == MAT_GLOW &&
|
| 76 |
|
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o->otype != OBJ_SOURCE &&
|
| 77 |
|
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m->oargs.farg[3] <= FTINY)
|
| 78 |
greg |
1.1 |
continue; /* don't bother */
|
| 79 |
greg |
2.16 |
if (m->oargs.farg[0] <= FTINY && m->oargs.farg[1] <= FTINY &&
|
| 80 |
|
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m->oargs.farg[2] <= FTINY)
|
| 81 |
|
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continue; /* don't bother */
|
| 82 |
greg |
1.1 |
|
| 83 |
greg |
1.35 |
if (sfun[o->otype].of == NULL ||
|
| 84 |
|
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sfun[o->otype].of->setsrc == NULL)
|
| 85 |
|
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objerror(o, USER, "illegal material");
|
| 86 |
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|
| 87 |
greg |
1.36 |
if ((ns = newsource()) < 0)
|
| 88 |
greg |
1.25 |
goto memerr;
|
| 89 |
greg |
1.1 |
|
| 90 |
greg |
1.37 |
setsource(&source[ns], o);
|
| 91 |
greg |
1.1 |
|
| 92 |
greg |
1.6 |
if (m->otype == MAT_GLOW) {
|
| 93 |
greg |
1.36 |
source[ns].sflags |= SPROX;
|
| 94 |
|
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source[ns].sl.prox = m->oargs.farg[3];
|
| 95 |
greg |
2.8 |
if (source[ns].sflags & SDISTANT)
|
| 96 |
greg |
1.36 |
source[ns].sflags |= SSKIP;
|
| 97 |
greg |
1.6 |
} else if (m->otype == MAT_SPOT) {
|
| 98 |
greg |
1.36 |
source[ns].sflags |= SSPOT;
|
| 99 |
|
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if ((source[ns].sl.s = makespot(m)) == NULL)
|
| 100 |
greg |
1.33 |
goto memerr;
|
| 101 |
greg |
1.38 |
if (source[ns].sflags & SFLAT &&
|
| 102 |
|
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!checkspot(source[ns].sl.s,source[ns].snorm)) {
|
| 103 |
|
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objerror(o, WARNING,
|
| 104 |
|
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"invalid spotlight direction");
|
| 105 |
|
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source[ns].sflags |= SSKIP;
|
| 106 |
|
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}
|
| 107 |
greg |
1.6 |
}
|
| 108 |
greg |
2.3 |
if (!(source[ns].sflags & SSKIP))
|
| 109 |
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foundsource++;
|
| 110 |
greg |
1.1 |
}
|
| 111 |
greg |
2.3 |
if (!foundsource) {
|
| 112 |
greg |
1.25 |
error(WARNING, "no light sources found");
|
| 113 |
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return;
|
| 114 |
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}
|
| 115 |
greg |
1.33 |
markvirtuals(); /* find and add virtual sources */
|
| 116 |
greg |
1.45 |
/* allocate our contribution arrays */
|
| 117 |
greg |
1.48 |
maxcntr = nsources + MAXSPART; /* start with this many */
|
| 118 |
greg |
1.45 |
srccnt = (CONTRIB *)malloc(maxcntr*sizeof(CONTRIB));
|
| 119 |
|
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cntord = (CNTPTR *)malloc(maxcntr*sizeof(CNTPTR));
|
| 120 |
greg |
1.48 |
if (srccnt == NULL | cntord == NULL)
|
| 121 |
greg |
1.33 |
goto memerr;
|
| 122 |
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return;
|
| 123 |
greg |
1.25 |
memerr:
|
| 124 |
|
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error(SYSTEM, "out of memory in marksources");
|
| 125 |
greg |
1.1 |
}
|
| 126 |
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|
| 127 |
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|
| 128 |
greg |
1.45 |
srcray(sr, r, si) /* send a ray to a source, return domega */
|
| 129 |
greg |
1.1 |
register RAY *sr; /* returned source ray */
|
| 130 |
|
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RAY *r; /* ray which hit object */
|
| 131 |
greg |
1.45 |
SRCINDEX *si; /* source sample index */
|
| 132 |
greg |
1.1 |
{
|
| 133 |
greg |
1.45 |
double d; /* distance to source */
|
| 134 |
|
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register SRCREC *srcp;
|
| 135 |
greg |
1.1 |
|
| 136 |
greg |
1.45 |
rayorigin(sr, r, SHADOW, 1.0); /* ignore limits */
|
| 137 |
greg |
1.1 |
|
| 138 |
greg |
1.47 |
while ((d = nextssamp(sr, si)) != 0.0) {
|
| 139 |
greg |
1.45 |
sr->rsrc = si->sn; /* remember source */
|
| 140 |
|
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srcp = source + si->sn;
|
| 141 |
|
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if (srcp->sflags & SDISTANT) {
|
| 142 |
greg |
2.18 |
if (srcp->sflags & SSPOT && spotout(sr, srcp->sl.s))
|
| 143 |
greg |
2.4 |
continue;
|
| 144 |
greg |
1.45 |
return(1); /* sample OK */
|
| 145 |
greg |
1.40 |
}
|
| 146 |
greg |
1.45 |
/* local source */
|
| 147 |
greg |
1.6 |
/* check proximity */
|
| 148 |
greg |
1.45 |
if (srcp->sflags & SPROX && d > srcp->sl.prox)
|
| 149 |
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continue;
|
| 150 |
greg |
1.6 |
/* check angle */
|
| 151 |
greg |
1.45 |
if (srcp->sflags & SSPOT) {
|
| 152 |
greg |
2.18 |
if (spotout(sr, srcp->sl.s))
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| 153 |
greg |
1.45 |
continue;
|
| 154 |
|
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/* adjust solid angle */
|
| 155 |
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si->dom *= d*d;
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| 156 |
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d += srcp->sl.s->flen;
|
| 157 |
|
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si->dom /= d*d;
|
| 158 |
greg |
1.1 |
}
|
| 159 |
greg |
1.45 |
return(1); /* sample OK */
|
| 160 |
|
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}
|
| 161 |
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return(0); /* no more samples */
|
| 162 |
greg |
1.1 |
}
|
| 163 |
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|
| 164 |
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|
| 165 |
greg |
1.35 |
srcvalue(r) /* punch ray to source and compute value */
|
| 166 |
greg |
2.15 |
register RAY *r;
|
| 167 |
greg |
1.1 |
{
|
| 168 |
greg |
1.35 |
register SRCREC *sp;
|
| 169 |
greg |
1.1 |
|
| 170 |
greg |
1.35 |
sp = &source[r->rsrc];
|
| 171 |
|
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if (sp->sflags & SVIRTUAL) { /* virtual source */
|
| 172 |
|
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/* check intersection */
|
| 173 |
|
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if (!(*ofun[sp->so->otype].funp)(sp->so, r))
|
| 174 |
|
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return;
|
| 175 |
greg |
2.15 |
if (!rayshade(r, r->ro->omod)) /* compute contribution */
|
| 176 |
|
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goto nomat;
|
| 177 |
greg |
2.19 |
rayparticipate(r);
|
| 178 |
greg |
1.35 |
return;
|
| 179 |
greg |
1.1 |
}
|
| 180 |
greg |
1.35 |
/* compute intersection */
|
| 181 |
|
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if (sp->sflags & SDISTANT ? sourcehit(r) :
|
| 182 |
|
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(*ofun[sp->so->otype].funp)(sp->so, r)) {
|
| 183 |
|
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if (sp->sa.success >= 0)
|
| 184 |
|
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sp->sa.success++;
|
| 185 |
greg |
2.15 |
if (!rayshade(r, r->ro->omod)) /* compute contribution */
|
| 186 |
|
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goto nomat;
|
| 187 |
greg |
2.19 |
rayparticipate(r);
|
| 188 |
greg |
1.35 |
return;
|
| 189 |
greg |
1.1 |
}
|
| 190 |
greg |
2.15 |
/* we missed our mark! */
|
| 191 |
greg |
1.35 |
if (sp->sa.success < 0)
|
| 192 |
|
|
return; /* bitched already */
|
| 193 |
|
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sp->sa.success -= AIMREQT;
|
| 194 |
|
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if (sp->sa.success >= 0)
|
| 195 |
|
|
return; /* leniency */
|
| 196 |
|
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sprintf(errmsg, "aiming failure for light source \"%s\"",
|
| 197 |
|
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sp->so->oname);
|
| 198 |
|
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error(WARNING, errmsg); /* issue warning */
|
| 199 |
greg |
2.15 |
return;
|
| 200 |
|
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nomat:
|
| 201 |
|
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objerror(r->ro, USER, "material not found");
|
| 202 |
greg |
1.1 |
}
|
| 203 |
|
|
|
| 204 |
|
|
|
| 205 |
greg |
2.5 |
sourcehit(r) /* check to see if ray hit distant source */
|
| 206 |
|
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register RAY *r;
|
| 207 |
|
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{
|
| 208 |
|
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int first, last;
|
| 209 |
|
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register int i;
|
| 210 |
|
|
|
| 211 |
|
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if (r->rsrc >= 0) { /* check only one if aimed */
|
| 212 |
|
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first = last = r->rsrc;
|
| 213 |
|
|
} else { /* otherwise check all */
|
| 214 |
|
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first = 0; last = nsources-1;
|
| 215 |
|
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}
|
| 216 |
|
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for (i = first; i <= last; i++)
|
| 217 |
|
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if ((source[i].sflags & (SDISTANT|SVIRTUAL)) == SDISTANT)
|
| 218 |
|
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/*
|
| 219 |
|
|
* Check to see if ray is within
|
| 220 |
|
|
* solid angle of source.
|
| 221 |
|
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*/
|
| 222 |
|
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if (2.0*PI * (1.0 - DOT(source[i].sloc,r->rdir))
|
| 223 |
|
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<= source[i].ss2) {
|
| 224 |
|
|
r->ro = source[i].so;
|
| 225 |
|
|
if (!(source[i].sflags & SSKIP))
|
| 226 |
|
|
break;
|
| 227 |
|
|
}
|
| 228 |
|
|
|
| 229 |
|
|
if (r->ro != NULL) {
|
| 230 |
|
|
for (i = 0; i < 3; i++)
|
| 231 |
|
|
r->ron[i] = -r->rdir[i];
|
| 232 |
|
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r->rod = 1.0;
|
| 233 |
|
|
r->rox = NULL;
|
| 234 |
|
|
return(1);
|
| 235 |
|
|
}
|
| 236 |
|
|
return(0);
|
| 237 |
|
|
}
|
| 238 |
|
|
|
| 239 |
|
|
|
| 240 |
greg |
1.4 |
static int
|
| 241 |
|
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cntcmp(sc1, sc2) /* contribution compare (descending) */
|
| 242 |
greg |
1.9 |
register CNTPTR *sc1, *sc2;
|
| 243 |
greg |
1.4 |
{
|
| 244 |
|
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if (sc1->brt > sc2->brt)
|
| 245 |
|
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return(-1);
|
| 246 |
|
|
if (sc1->brt < sc2->brt)
|
| 247 |
|
|
return(1);
|
| 248 |
|
|
return(0);
|
| 249 |
|
|
}
|
| 250 |
|
|
|
| 251 |
|
|
|
| 252 |
|
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direct(r, f, p) /* add direct component */
|
| 253 |
|
|
RAY *r; /* ray that hit surface */
|
| 254 |
|
|
int (*f)(); /* direct component coefficient function */
|
| 255 |
|
|
char *p; /* data for f */
|
| 256 |
|
|
{
|
| 257 |
greg |
1.42 |
extern int (*trace)();
|
| 258 |
greg |
1.4 |
register int sn;
|
| 259 |
greg |
2.7 |
register CONTRIB *scp;
|
| 260 |
greg |
1.45 |
SRCINDEX si;
|
| 261 |
greg |
1.12 |
int nshadcheck, ncnts;
|
| 262 |
greg |
1.29 |
int nhits;
|
| 263 |
greg |
1.45 |
double prob, ourthresh, hwt;
|
| 264 |
greg |
1.4 |
RAY sr;
|
| 265 |
greg |
1.25 |
/* NOTE: srccnt and cntord global so no recursion */
|
| 266 |
greg |
1.22 |
if (nsources <= 0)
|
| 267 |
greg |
1.25 |
return; /* no sources?! */
|
| 268 |
greg |
1.4 |
/* potential contributions */
|
| 269 |
greg |
1.45 |
initsrcindex(&si);
|
| 270 |
|
|
for (sn = 0; srcray(&sr, r, &si); sn++) {
|
| 271 |
|
|
if (sn >= maxcntr) {
|
| 272 |
|
|
maxcntr = sn + MAXSPART;
|
| 273 |
|
|
srccnt = (CONTRIB *)realloc((char *)srccnt,
|
| 274 |
|
|
maxcntr*sizeof(CONTRIB));
|
| 275 |
|
|
cntord = (CNTPTR *)realloc((char *)cntord,
|
| 276 |
|
|
maxcntr*sizeof(CNTPTR));
|
| 277 |
greg |
1.48 |
if (srccnt == NULL | cntord == NULL)
|
| 278 |
greg |
1.45 |
error(SYSTEM, "out of memory in direct");
|
| 279 |
|
|
}
|
| 280 |
|
|
cntord[sn].sndx = sn;
|
| 281 |
greg |
2.7 |
scp = srccnt + sn;
|
| 282 |
|
|
scp->sno = sr.rsrc;
|
| 283 |
greg |
1.4 |
/* compute coefficient */
|
| 284 |
greg |
2.7 |
(*f)(scp->coef, p, sr.rdir, si.dom);
|
| 285 |
|
|
cntord[sn].brt = bright(scp->coef);
|
| 286 |
greg |
1.15 |
if (cntord[sn].brt <= 0.0)
|
| 287 |
greg |
1.4 |
continue;
|
| 288 |
greg |
2.7 |
VCOPY(scp->dir, sr.rdir);
|
| 289 |
greg |
1.35 |
/* compute potential */
|
| 290 |
|
|
sr.revf = srcvalue;
|
| 291 |
|
|
rayvalue(&sr);
|
| 292 |
greg |
2.7 |
copycolor(scp->val, sr.rcol);
|
| 293 |
|
|
multcolor(scp->val, scp->coef);
|
| 294 |
|
|
cntord[sn].brt = bright(scp->val);
|
| 295 |
greg |
1.4 |
}
|
| 296 |
|
|
/* sort contributions */
|
| 297 |
greg |
1.45 |
qsort(cntord, sn, sizeof(CNTPTR), cntcmp);
|
| 298 |
greg |
1.13 |
{ /* find last */
|
| 299 |
|
|
register int l, m;
|
| 300 |
|
|
|
| 301 |
greg |
1.45 |
ncnts = l = sn;
|
| 302 |
|
|
sn = 0;
|
| 303 |
greg |
1.13 |
while ((m = (sn + ncnts) >> 1) != l) {
|
| 304 |
|
|
if (cntord[m].brt > 0.0)
|
| 305 |
|
|
sn = m;
|
| 306 |
|
|
else
|
| 307 |
|
|
ncnts = m;
|
| 308 |
|
|
l = m;
|
| 309 |
|
|
}
|
| 310 |
|
|
}
|
| 311 |
greg |
2.2 |
if (ncnts == 0)
|
| 312 |
|
|
return; /* no contributions! */
|
| 313 |
greg |
1.12 |
/* accumulate tail */
|
| 314 |
|
|
for (sn = ncnts-1; sn > 0; sn--)
|
| 315 |
|
|
cntord[sn-1].brt += cntord[sn].brt;
|
| 316 |
greg |
1.45 |
/* compute number to check */
|
| 317 |
|
|
nshadcheck = pow((double)ncnts, shadcert) + .5;
|
| 318 |
|
|
/* modify threshold */
|
| 319 |
|
|
ourthresh = shadthresh / r->rweight;
|
| 320 |
greg |
1.10 |
/* test for shadows */
|
| 321 |
greg |
2.13 |
for (nhits = 0, hwt = 0.0, sn = 0; sn < ncnts;
|
| 322 |
|
|
hwt += (double)source[scp->sno].nhits /
|
| 323 |
|
|
(double)source[scp->sno].ntests,
|
| 324 |
|
|
sn++) {
|
| 325 |
greg |
1.10 |
/* check threshold */
|
| 326 |
greg |
1.12 |
if ((sn+nshadcheck>=ncnts ? cntord[sn].brt :
|
| 327 |
greg |
1.27 |
cntord[sn].brt-cntord[sn+nshadcheck].brt)
|
| 328 |
|
|
< ourthresh*bright(r->rcol))
|
| 329 |
greg |
1.4 |
break;
|
| 330 |
greg |
2.7 |
scp = srccnt + cntord[sn].sndx;
|
| 331 |
greg |
1.4 |
/* test for hit */
|
| 332 |
|
|
rayorigin(&sr, r, SHADOW, 1.0);
|
| 333 |
greg |
2.7 |
VCOPY(sr.rdir, scp->dir);
|
| 334 |
|
|
sr.rsrc = scp->sno;
|
| 335 |
|
|
source[scp->sno].ntests++; /* keep statistics */
|
| 336 |
greg |
1.4 |
if (localhit(&sr, &thescene) &&
|
| 337 |
greg |
2.7 |
( sr.ro != source[scp->sno].so ||
|
| 338 |
|
|
source[scp->sno].sflags & SFOLLOW )) {
|
| 339 |
greg |
1.33 |
/* follow entire path */
|
| 340 |
greg |
2.23 |
raycont(&sr);
|
| 341 |
greg |
2.19 |
rayparticipate(&sr);
|
| 342 |
greg |
1.42 |
if (trace != NULL)
|
| 343 |
|
|
(*trace)(&sr); /* trace execution */
|
| 344 |
greg |
1.5 |
if (bright(sr.rcol) <= FTINY)
|
| 345 |
greg |
1.4 |
continue; /* missed! */
|
| 346 |
greg |
2.7 |
copycolor(scp->val, sr.rcol);
|
| 347 |
|
|
multcolor(scp->val, scp->coef);
|
| 348 |
greg |
1.4 |
}
|
| 349 |
|
|
/* add contribution if hit */
|
| 350 |
greg |
2.7 |
addcolor(r->rcol, scp->val);
|
| 351 |
greg |
1.29 |
nhits++;
|
| 352 |
greg |
2.7 |
source[scp->sno].nhits++;
|
| 353 |
greg |
1.4 |
}
|
| 354 |
greg |
2.13 |
/* source hit rate */
|
| 355 |
|
|
if (hwt > FTINY)
|
| 356 |
|
|
hwt = (double)nhits / hwt;
|
| 357 |
greg |
1.29 |
else
|
| 358 |
|
|
hwt = 0.5;
|
| 359 |
greg |
1.20 |
#ifdef DEBUG
|
| 360 |
greg |
2.13 |
sprintf(errmsg, "%d tested, %d untested, %f conditional hit rate\n",
|
| 361 |
greg |
1.12 |
sn, ncnts-sn, hwt);
|
| 362 |
|
|
eputs(errmsg);
|
| 363 |
greg |
1.4 |
#endif
|
| 364 |
|
|
/* add in untested sources */
|
| 365 |
greg |
1.12 |
for ( ; sn < ncnts; sn++) {
|
| 366 |
greg |
2.7 |
scp = srccnt + cntord[sn].sndx;
|
| 367 |
|
|
prob = hwt * (double)source[scp->sno].nhits /
|
| 368 |
|
|
(double)source[scp->sno].ntests;
|
| 369 |
greg |
2.13 |
if (prob > 1.0)
|
| 370 |
|
|
prob = 1.0;
|
| 371 |
greg |
2.7 |
scalecolor(scp->val, prob);
|
| 372 |
|
|
addcolor(r->rcol, scp->val);
|
| 373 |
greg |
2.19 |
}
|
| 374 |
|
|
}
|
| 375 |
|
|
|
| 376 |
|
|
|
| 377 |
|
|
srcscatter(r) /* compute source scattering into ray */
|
| 378 |
|
|
register RAY *r;
|
| 379 |
|
|
{
|
| 380 |
greg |
2.20 |
int oldsampndx;
|
| 381 |
greg |
2.19 |
int nsamps;
|
| 382 |
|
|
RAY sr;
|
| 383 |
|
|
SRCINDEX si;
|
| 384 |
greg |
2.25 |
double t, d;
|
| 385 |
|
|
double re, ge, be;
|
| 386 |
|
|
COLOR cvext;
|
| 387 |
greg |
2.19 |
int i, j;
|
| 388 |
|
|
|
| 389 |
greg |
2.22 |
if (r->slights == NULL || r->slights[0] == 0
|
| 390 |
|
|
|| r->gecc >= 1.-FTINY || r->rot >= FHUGE)
|
| 391 |
greg |
2.19 |
return;
|
| 392 |
|
|
if (ssampdist <= FTINY || (nsamps = r->rot/ssampdist + .5) < 1)
|
| 393 |
|
|
nsamps = 1;
|
| 394 |
greg |
2.22 |
#if MAXSSAMP
|
| 395 |
|
|
else if (nsamps > MAXSSAMP)
|
| 396 |
|
|
nsamps = MAXSSAMP;
|
| 397 |
|
|
#endif
|
| 398 |
greg |
2.20 |
oldsampndx = samplendx;
|
| 399 |
|
|
samplendx = random()&0x7fff; /* randomize */
|
| 400 |
greg |
2.19 |
for (i = r->slights[0]; i > 0; i--) { /* for each source */
|
| 401 |
greg |
2.25 |
for (j = 0; j < nsamps; j++) { /* for each sample position */
|
| 402 |
greg |
2.19 |
samplendx++;
|
| 403 |
|
|
t = r->rot * (j+frandom())/nsamps;
|
| 404 |
greg |
2.25 |
/* extinction */
|
| 405 |
|
|
re = t*colval(r->cext,RED);
|
| 406 |
|
|
ge = t*colval(r->cext,GRN);
|
| 407 |
|
|
be = t*colval(r->cext,BLU);
|
| 408 |
|
|
setcolor(cvext, re > 92. ? 0. : exp(-re),
|
| 409 |
|
|
ge > 92. ? 0. : exp(-ge),
|
| 410 |
|
|
be > 92. ? 0. : exp(-be));
|
| 411 |
|
|
if (intens(cvext) <= FTINY)
|
| 412 |
|
|
break; /* too far away */
|
| 413 |
greg |
2.19 |
sr.rorg[0] = r->rorg[0] + r->rdir[0]*t;
|
| 414 |
|
|
sr.rorg[1] = r->rorg[1] + r->rdir[1]*t;
|
| 415 |
|
|
sr.rorg[2] = r->rorg[2] + r->rdir[2]*t;
|
| 416 |
|
|
sr.rmax = 0.;
|
| 417 |
greg |
2.21 |
initsrcindex(&si); /* sample ray to this source */
|
| 418 |
|
|
si.sn = r->slights[i];
|
| 419 |
|
|
nopart(&si, &sr);
|
| 420 |
|
|
if (!srcray(&sr, NULL, &si) ||
|
| 421 |
|
|
sr.rsrc != r->slights[i])
|
| 422 |
|
|
continue; /* no path */
|
| 423 |
greg |
2.19 |
copycolor(sr.cext, r->cext);
|
| 424 |
greg |
2.24 |
copycolor(sr.albedo, r->albedo);
|
| 425 |
greg |
2.19 |
sr.gecc = r->gecc;
|
| 426 |
gregl |
2.26 |
sr.slights = r->slights;
|
| 427 |
greg |
2.19 |
rayvalue(&sr); /* eval. source ray */
|
| 428 |
|
|
if (bright(sr.rcol) <= FTINY)
|
| 429 |
|
|
continue;
|
| 430 |
|
|
if (r->gecc <= FTINY) /* compute P(theta) */
|
| 431 |
|
|
d = 1.;
|
| 432 |
|
|
else {
|
| 433 |
|
|
d = DOT(r->rdir, sr.rdir);
|
| 434 |
greg |
2.25 |
d = 1. + r->gecc*r->gecc - 2.*r->gecc*d;
|
| 435 |
|
|
d = (1. - r->gecc*r->gecc) / (d*sqrt(d));
|
| 436 |
greg |
2.19 |
}
|
| 437 |
|
|
/* other factors */
|
| 438 |
greg |
2.24 |
d *= si.dom * r->rot / (4.*PI*nsamps);
|
| 439 |
greg |
2.19 |
multcolor(sr.rcol, r->cext);
|
| 440 |
greg |
2.24 |
multcolor(sr.rcol, r->albedo);
|
| 441 |
greg |
2.19 |
scalecolor(sr.rcol, d);
|
| 442 |
greg |
2.25 |
multcolor(sr.rcol, cvext);
|
| 443 |
|
|
addcolor(r->rcol, sr.rcol); /* add it in */
|
| 444 |
greg |
2.19 |
}
|
| 445 |
greg |
1.1 |
}
|
| 446 |
greg |
2.20 |
samplendx = oldsampndx;
|
| 447 |
greg |
2.4 |
}
|
| 448 |
|
|
|
| 449 |
|
|
|
| 450 |
|
|
/****************************************************************
|
| 451 |
|
|
* The following macros were separated from the m_light() routine
|
| 452 |
|
|
* because they are very nasty and difficult to understand.
|
| 453 |
|
|
*/
|
| 454 |
|
|
|
| 455 |
greg |
2.11 |
/* illumblock *
|
| 456 |
greg |
2.4 |
*
|
| 457 |
|
|
* We cannot allow an illum to pass to another illum, because that
|
| 458 |
|
|
* would almost certainly constitute overcounting.
|
| 459 |
|
|
* However, we do allow an illum to pass to another illum
|
| 460 |
|
|
* that is actually going to relay to a virtual light source.
|
| 461 |
greg |
2.11 |
* We also prevent an illum from passing to a glow; this provides a
|
| 462 |
|
|
* convenient mechanism for defining detailed light source
|
| 463 |
|
|
* geometry behind (or inside) an effective radiator.
|
| 464 |
greg |
2.4 |
*/
|
| 465 |
|
|
|
| 466 |
greg |
2.11 |
static int weaksrcmod(obj) int obj; /* efficiency booster function */
|
| 467 |
|
|
{register OBJREC *o = objptr(obj);
|
| 468 |
|
|
return(o->otype==MAT_ILLUM|o->otype==MAT_GLOW);}
|
| 469 |
greg |
2.4 |
|
| 470 |
greg |
2.11 |
#define illumblock(m, r) (!(source[r->rsrc].sflags&SVIRTUAL) && \
|
| 471 |
greg |
2.12 |
r->rod > 0.0 && \
|
| 472 |
greg |
2.11 |
weaksrcmod(source[r->rsrc].so->omod))
|
| 473 |
|
|
|
| 474 |
greg |
2.4 |
/* wrongsource *
|
| 475 |
|
|
*
|
| 476 |
|
|
* This source is the wrong source (ie. overcounted) if we are
|
| 477 |
|
|
* aimed to a different source than the one we hit and the one
|
| 478 |
greg |
2.11 |
* we hit is not an illum that should be passed.
|
| 479 |
greg |
2.4 |
*/
|
| 480 |
|
|
|
| 481 |
|
|
#define wrongsource(m, r) (r->rsrc>=0 && source[r->rsrc].so!=r->ro && \
|
| 482 |
greg |
2.11 |
(m->otype!=MAT_ILLUM || illumblock(m,r)))
|
| 483 |
greg |
2.4 |
|
| 484 |
|
|
/* distglow *
|
| 485 |
|
|
*
|
| 486 |
|
|
* A distant glow is an object that sometimes acts as a light source,
|
| 487 |
|
|
* but is too far away from the test point to be one in this case.
|
| 488 |
greg |
2.11 |
* (Glows with negative radii should NEVER participate in illumination.)
|
| 489 |
greg |
2.4 |
*/
|
| 490 |
|
|
|
| 491 |
greg |
2.17 |
#define distglow(m, r, d) (m->otype==MAT_GLOW && \
|
| 492 |
greg |
2.10 |
m->oargs.farg[3] >= -FTINY && \
|
| 493 |
greg |
2.17 |
d > m->oargs.farg[3])
|
| 494 |
greg |
2.4 |
|
| 495 |
|
|
/* badcomponent *
|
| 496 |
|
|
*
|
| 497 |
|
|
* We must avoid counting light sources in the ambient calculation,
|
| 498 |
|
|
* since the direct component is handled separately. Therefore, any
|
| 499 |
|
|
* ambient ray which hits an active light source must be discarded.
|
| 500 |
|
|
* The same is true for stray specular samples, since the specular
|
| 501 |
|
|
* contribution from light sources is calculated separately.
|
| 502 |
|
|
*/
|
| 503 |
|
|
|
| 504 |
|
|
#define badcomponent(m, r) (r->crtype&(AMBIENT|SPECULAR) && \
|
| 505 |
|
|
!(r->crtype&SHADOW || r->rod < 0.0 || \
|
| 506 |
greg |
2.17 |
/* not 100% correct */ distglow(m, r, r->rot)))
|
| 507 |
greg |
2.4 |
|
| 508 |
|
|
/* passillum *
|
| 509 |
|
|
*
|
| 510 |
|
|
* An illum passes to another material type when we didn't hit it
|
| 511 |
|
|
* on purpose (as part of a direct calculation), or it is relaying
|
| 512 |
|
|
* a virtual light source.
|
| 513 |
|
|
*/
|
| 514 |
|
|
|
| 515 |
|
|
#define passillum(m, r) (m->otype==MAT_ILLUM && \
|
| 516 |
|
|
(r->rsrc<0 || source[r->rsrc].so!=r->ro || \
|
| 517 |
|
|
source[r->rsrc].sflags&SVIRTUAL))
|
| 518 |
|
|
|
| 519 |
|
|
/* srcignore *
|
| 520 |
|
|
*
|
| 521 |
greg |
2.10 |
* The -dv flag is normally on for sources to be visible.
|
| 522 |
greg |
2.4 |
*/
|
| 523 |
|
|
|
| 524 |
greg |
2.17 |
#define srcignore(m, r) !(directvis || r->crtype&SHADOW || \
|
| 525 |
|
|
distglow(m, r, raydist(r,PRIMARY)))
|
| 526 |
greg |
2.4 |
|
| 527 |
|
|
|
| 528 |
|
|
m_light(m, r) /* ray hit a light source */
|
| 529 |
|
|
register OBJREC *m;
|
| 530 |
|
|
register RAY *r;
|
| 531 |
|
|
{
|
| 532 |
|
|
/* check for over-counting */
|
| 533 |
greg |
2.12 |
if (badcomponent(m, r))
|
| 534 |
greg |
2.14 |
return(1);
|
| 535 |
greg |
2.17 |
if (wrongsource(m, r))
|
| 536 |
greg |
2.14 |
return(1);
|
| 537 |
greg |
2.4 |
/* check for passed illum */
|
| 538 |
|
|
if (passillum(m, r)) {
|
| 539 |
greg |
2.14 |
if (m->oargs.nsargs && strcmp(m->oargs.sarg[0], VOIDID))
|
| 540 |
|
|
return(rayshade(r, modifier(m->oargs.sarg[0])));
|
| 541 |
|
|
raytrans(r);
|
| 542 |
|
|
return(1);
|
| 543 |
greg |
2.4 |
}
|
| 544 |
|
|
/* otherwise treat as source */
|
| 545 |
|
|
/* check for behind */
|
| 546 |
|
|
if (r->rod < 0.0)
|
| 547 |
greg |
2.14 |
return(1);
|
| 548 |
greg |
2.4 |
/* check for invisibility */
|
| 549 |
|
|
if (srcignore(m, r))
|
| 550 |
greg |
2.14 |
return(1);
|
| 551 |
greg |
2.4 |
/* check for outside spot */
|
| 552 |
greg |
2.18 |
if (m->otype==MAT_SPOT && spotout(r, makespot(m)))
|
| 553 |
greg |
2.14 |
return(1);
|
| 554 |
greg |
2.4 |
/* get distribution pattern */
|
| 555 |
|
|
raytexture(r, m->omod);
|
| 556 |
|
|
/* get source color */
|
| 557 |
|
|
setcolor(r->rcol, m->oargs.farg[0],
|
| 558 |
|
|
m->oargs.farg[1],
|
| 559 |
|
|
m->oargs.farg[2]);
|
| 560 |
|
|
/* modify value */
|
| 561 |
|
|
multcolor(r->rcol, r->pcol);
|
| 562 |
greg |
2.14 |
return(1);
|
| 563 |
greg |
1.1 |
}
|
