1 |
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/* Copyright (c) 1991 Regents of the University of California */ |
2 |
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|
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#ifndef lint |
2 |
< |
static char SCCSid[] = "$SunId$ LBL"; |
2 |
> |
static const char RCSid[] = "$Id$"; |
3 |
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#endif |
6 |
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|
4 |
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/* |
5 |
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* source.c - routines dealing with illumination sources. |
6 |
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* |
7 |
< |
* 8/20/85 |
7 |
> |
* External symbols declared in source.h |
8 |
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*/ |
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|
10 |
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#include "copyright.h" |
11 |
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|
12 |
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#include "ray.h" |
13 |
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|
15 |
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#include "octree.h" |
16 |
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|
14 |
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#include "otypes.h" |
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|
16 |
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#include "source.h" |
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|
18 |
+ |
#include "random.h" |
19 |
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|
20 |
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extern double ssampdist; /* scatter sampling distance */ |
21 |
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|
22 |
+ |
#ifndef MAXSSAMP |
23 |
+ |
#define MAXSSAMP 16 /* maximum samples per ray */ |
24 |
+ |
#endif |
25 |
+ |
|
26 |
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/* |
27 |
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* Structures used by direct() |
28 |
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*/ |
44 |
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static int maxcntr = 0; /* size of contribution arrays */ |
45 |
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|
46 |
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|
47 |
+ |
void |
48 |
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marksources() /* find and mark source objects */ |
49 |
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{ |
50 |
+ |
int foundsource = 0; |
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int i; |
52 |
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register OBJREC *o, *m; |
53 |
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register int ns; |
54 |
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/* initialize dispatch table */ |
55 |
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initstypes(); |
56 |
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/* find direct sources */ |
57 |
< |
for (i = 0; i < nobjects; i++) { |
57 |
> |
for (i = 0; i < nsceneobjs; i++) { |
58 |
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|
59 |
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o = objptr(i); |
60 |
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|
61 |
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if (!issurface(o->otype) || o->omod == OVOID) |
62 |
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continue; |
63 |
< |
|
63 |
> |
/* find material */ |
64 |
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m = objptr(o->omod); |
65 |
< |
|
66 |
< |
if (!islight(m->otype)) |
67 |
< |
continue; |
65 |
> |
while (!ismaterial(m->otype)) |
66 |
> |
if (ismixture(m->otype) || m->omod == OVOID) { |
67 |
> |
m = NULL; |
68 |
> |
break; |
69 |
> |
} else |
70 |
> |
m = objptr(m->omod); |
71 |
> |
if (m == NULL || !islight(m->otype)) |
72 |
> |
continue; /* not source modifier */ |
73 |
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|
74 |
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if (m->oargs.nfargs != (m->otype == MAT_GLOW ? 4 : |
75 |
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m->otype == MAT_SPOT ? 7 : 3)) |
79 |
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o->otype != OBJ_SOURCE && |
80 |
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m->oargs.farg[3] <= FTINY) |
81 |
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continue; /* don't bother */ |
82 |
+ |
if (m->oargs.farg[0] <= FTINY && m->oargs.farg[1] <= FTINY && |
83 |
+ |
m->oargs.farg[2] <= FTINY) |
84 |
+ |
continue; /* don't bother */ |
85 |
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|
86 |
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if (sfun[o->otype].of == NULL || |
87 |
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sfun[o->otype].of->setsrc == NULL) |
95 |
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if (m->otype == MAT_GLOW) { |
96 |
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source[ns].sflags |= SPROX; |
97 |
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source[ns].sl.prox = m->oargs.farg[3]; |
98 |
< |
if (o->otype == OBJ_SOURCE) |
98 |
> |
if (source[ns].sflags & SDISTANT) |
99 |
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source[ns].sflags |= SSKIP; |
100 |
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} else if (m->otype == MAT_SPOT) { |
101 |
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source[ns].sflags |= SSPOT; |
108 |
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source[ns].sflags |= SSKIP; |
109 |
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} |
110 |
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} |
111 |
+ |
if (!(source[ns].sflags & SSKIP)) |
112 |
+ |
foundsource++; |
113 |
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} |
114 |
< |
if (nsources <= 0) { |
114 |
> |
if (!foundsource) { |
115 |
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error(WARNING, "no light sources found"); |
116 |
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return; |
117 |
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} |
118 |
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markvirtuals(); /* find and add virtual sources */ |
119 |
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/* allocate our contribution arrays */ |
120 |
< |
maxcntr = nsources + MAXSPART*2; /* start with this many */ |
120 |
> |
maxcntr = nsources + MAXSPART; /* start with this many */ |
121 |
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srccnt = (CONTRIB *)malloc(maxcntr*sizeof(CONTRIB)); |
122 |
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cntord = (CNTPTR *)malloc(maxcntr*sizeof(CNTPTR)); |
123 |
< |
if (srccnt == NULL || cntord == NULL) |
123 |
> |
if ((srccnt == NULL) | (cntord == NULL)) |
124 |
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goto memerr; |
125 |
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return; |
126 |
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memerr: |
128 |
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} |
129 |
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|
130 |
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|
131 |
+ |
void |
132 |
+ |
freesources() /* free all source structures */ |
133 |
+ |
{ |
134 |
+ |
if (nsources > 0) { |
135 |
+ |
free((void *)source); |
136 |
+ |
source = NULL; |
137 |
+ |
nsources = 0; |
138 |
+ |
} |
139 |
+ |
if (maxcntr <= 0) |
140 |
+ |
return; |
141 |
+ |
free((void *)srccnt); |
142 |
+ |
srccnt = NULL; |
143 |
+ |
free((void *)cntord); |
144 |
+ |
cntord = NULL; |
145 |
+ |
maxcntr = 0; |
146 |
+ |
} |
147 |
+ |
|
148 |
+ |
|
149 |
+ |
int |
150 |
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srcray(sr, r, si) /* send a ray to a source, return domega */ |
151 |
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register RAY *sr; /* returned source ray */ |
152 |
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RAY *r; /* ray which hit object */ |
153 |
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SRCINDEX *si; /* source sample index */ |
154 |
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{ |
155 |
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double d; /* distance to source */ |
120 |
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FVECT vd; |
156 |
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register SRCREC *srcp; |
122 |
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register int i; |
157 |
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|
158 |
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rayorigin(sr, r, SHADOW, 1.0); /* ignore limits */ |
159 |
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|
160 |
< |
while ((d = nextssamp(sr->rorg, sr->rdir, si)) != 0.0) { |
160 |
> |
while ((d = nextssamp(sr, si)) != 0.0) { |
161 |
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sr->rsrc = si->sn; /* remember source */ |
162 |
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srcp = source + si->sn; |
163 |
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if (srcp->sflags & SDISTANT) { |
164 |
< |
if (srcp->sflags & SSPOT) { /* check location */ |
165 |
< |
for (i = 0; i < 3; i++) |
132 |
< |
vd[i] = srcp->sl.s->aim[i] - sr->rorg[i]; |
133 |
< |
d = DOT(sr->rdir,vd); |
134 |
< |
if (d <= FTINY) |
135 |
< |
continue; |
136 |
< |
d = DOT(vd,vd) - d*d; |
137 |
< |
if (PI*d > srcp->sl.s->siz) |
138 |
< |
continue; |
139 |
< |
} |
164 |
> |
if (srcp->sflags & SSPOT && spotout(sr, srcp->sl.s)) |
165 |
> |
continue; |
166 |
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return(1); /* sample OK */ |
167 |
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} |
168 |
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/* local source */ |
171 |
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continue; |
172 |
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/* check angle */ |
173 |
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if (srcp->sflags & SSPOT) { |
174 |
< |
if (srcp->sl.s->siz < 2.0*PI * |
149 |
< |
(1.0 + DOT(srcp->sl.s->aim,sr->rdir))) |
174 |
> |
if (spotout(sr, srcp->sl.s)) |
175 |
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continue; |
176 |
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/* adjust solid angle */ |
177 |
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si->dom *= d*d; |
184 |
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} |
185 |
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|
186 |
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|
187 |
+ |
void |
188 |
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srcvalue(r) /* punch ray to source and compute value */ |
189 |
< |
RAY *r; |
189 |
> |
register RAY *r; |
190 |
|
{ |
191 |
|
register SRCREC *sp; |
192 |
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|
195 |
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/* check intersection */ |
196 |
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if (!(*ofun[sp->so->otype].funp)(sp->so, r)) |
197 |
|
return; |
198 |
< |
raycont(r); /* compute contribution */ |
198 |
> |
if (!rayshade(r, r->ro->omod)) /* compute contribution */ |
199 |
> |
goto nomat; |
200 |
> |
rayparticipate(r); |
201 |
|
return; |
202 |
|
} |
203 |
|
/* compute intersection */ |
205 |
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(*ofun[sp->so->otype].funp)(sp->so, r)) { |
206 |
|
if (sp->sa.success >= 0) |
207 |
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sp->sa.success++; |
208 |
< |
raycont(r); /* compute contribution */ |
208 |
> |
if (!rayshade(r, r->ro->omod)) /* compute contribution */ |
209 |
> |
goto nomat; |
210 |
> |
rayparticipate(r); |
211 |
|
return; |
212 |
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} |
213 |
+ |
/* we missed our mark! */ |
214 |
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if (sp->sa.success < 0) |
215 |
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return; /* bitched already */ |
216 |
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sp->sa.success -= AIMREQT; |
219 |
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sprintf(errmsg, "aiming failure for light source \"%s\"", |
220 |
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sp->so->oname); |
221 |
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error(WARNING, errmsg); /* issue warning */ |
222 |
+ |
return; |
223 |
+ |
nomat: |
224 |
+ |
objerror(r->ro, USER, "material not found"); |
225 |
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} |
226 |
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|
227 |
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|
228 |
+ |
int |
229 |
+ |
sourcehit(r) /* check to see if ray hit distant source */ |
230 |
+ |
register RAY *r; |
231 |
+ |
{ |
232 |
+ |
int first, last; |
233 |
+ |
register int i; |
234 |
+ |
|
235 |
+ |
if (r->rsrc >= 0) { /* check only one if aimed */ |
236 |
+ |
first = last = r->rsrc; |
237 |
+ |
} else { /* otherwise check all */ |
238 |
+ |
first = 0; last = nsources-1; |
239 |
+ |
} |
240 |
+ |
for (i = first; i <= last; i++) |
241 |
+ |
if ((source[i].sflags & (SDISTANT|SVIRTUAL)) == SDISTANT) |
242 |
+ |
/* |
243 |
+ |
* Check to see if ray is within |
244 |
+ |
* solid angle of source. |
245 |
+ |
*/ |
246 |
+ |
if (2.0*PI * (1.0 - DOT(source[i].sloc,r->rdir)) |
247 |
+ |
<= source[i].ss2) { |
248 |
+ |
r->ro = source[i].so; |
249 |
+ |
if (!(source[i].sflags & SSKIP)) |
250 |
+ |
break; |
251 |
+ |
} |
252 |
+ |
|
253 |
+ |
if (r->ro != NULL) { |
254 |
+ |
r->robj = objndx(r->ro); |
255 |
+ |
for (i = 0; i < 3; i++) |
256 |
+ |
r->ron[i] = -r->rdir[i]; |
257 |
+ |
r->rod = 1.0; |
258 |
+ |
r->pert[0] = r->pert[1] = r->pert[2] = 0.0; |
259 |
+ |
r->uv[0] = r->uv[1] = 0.0; |
260 |
+ |
r->rox = NULL; |
261 |
+ |
return(1); |
262 |
+ |
} |
263 |
+ |
return(0); |
264 |
+ |
} |
265 |
+ |
|
266 |
+ |
|
267 |
|
static int |
268 |
|
cntcmp(sc1, sc2) /* contribution compare (descending) */ |
269 |
|
register CNTPTR *sc1, *sc2; |
276 |
|
} |
277 |
|
|
278 |
|
|
279 |
+ |
void |
280 |
|
direct(r, f, p) /* add direct component */ |
281 |
|
RAY *r; /* ray that hit surface */ |
282 |
< |
int (*f)(); /* direct component coefficient function */ |
282 |
> |
void (*f)(); /* direct component coefficient function */ |
283 |
|
char *p; /* data for f */ |
284 |
|
{ |
285 |
< |
extern int (*trace)(); |
212 |
< |
extern double pow(); |
285 |
> |
extern void (*trace)(); |
286 |
|
register int sn; |
287 |
+ |
register CONTRIB *scp; |
288 |
|
SRCINDEX si; |
289 |
|
int nshadcheck, ncnts; |
290 |
|
int nhits; |
298 |
|
for (sn = 0; srcray(&sr, r, &si); sn++) { |
299 |
|
if (sn >= maxcntr) { |
300 |
|
maxcntr = sn + MAXSPART; |
301 |
< |
srccnt = (CONTRIB *)realloc((char *)srccnt, |
301 |
> |
srccnt = (CONTRIB *)realloc((void *)srccnt, |
302 |
|
maxcntr*sizeof(CONTRIB)); |
303 |
< |
cntord = (CNTPTR *)realloc((char *)cntord, |
303 |
> |
cntord = (CNTPTR *)realloc((void *)cntord, |
304 |
|
maxcntr*sizeof(CNTPTR)); |
305 |
< |
if (srccnt == NULL || cntord == NULL) |
305 |
> |
if ((srccnt == NULL) | (cntord == NULL)) |
306 |
|
error(SYSTEM, "out of memory in direct"); |
307 |
|
} |
308 |
|
cntord[sn].sndx = sn; |
309 |
< |
cntord[sn].brt = 0.0; |
309 |
> |
scp = srccnt + sn; |
310 |
> |
scp->sno = sr.rsrc; |
311 |
|
/* compute coefficient */ |
312 |
< |
(*f)(srccnt[sn].coef, p, srccnt[sn].dir, si.dom); |
313 |
< |
cntord[sn].brt = bright(srccnt[sn].coef); |
312 |
> |
(*f)(scp->coef, p, sr.rdir, si.dom); |
313 |
> |
cntord[sn].brt = bright(scp->coef); |
314 |
|
if (cntord[sn].brt <= 0.0) |
315 |
|
continue; |
316 |
< |
VCOPY(srccnt[sn].dir, sr.rdir); |
316 |
> |
VCOPY(scp->dir, sr.rdir); |
317 |
|
/* compute potential */ |
318 |
|
sr.revf = srcvalue; |
319 |
|
rayvalue(&sr); |
320 |
< |
copycolor(srccnt[sn].val, sr.rcol); |
321 |
< |
multcolor(srccnt[sn].val, srccnt[sn].coef); |
322 |
< |
cntord[sn].brt = bright(srccnt[sn].val); |
320 |
> |
copycolor(scp->val, sr.rcol); |
321 |
> |
multcolor(scp->val, scp->coef); |
322 |
> |
cntord[sn].brt = bright(scp->val); |
323 |
|
} |
324 |
|
/* sort contributions */ |
325 |
|
qsort(cntord, sn, sizeof(CNTPTR), cntcmp); |
336 |
|
l = m; |
337 |
|
} |
338 |
|
} |
339 |
+ |
if (ncnts == 0) |
340 |
+ |
return; /* no contributions! */ |
341 |
|
/* accumulate tail */ |
342 |
|
for (sn = ncnts-1; sn > 0; sn--) |
343 |
|
cntord[sn-1].brt += cntord[sn].brt; |
346 |
|
/* modify threshold */ |
347 |
|
ourthresh = shadthresh / r->rweight; |
348 |
|
/* test for shadows */ |
349 |
< |
nhits = 0; |
350 |
< |
for (sn = 0; sn < ncnts; sn++) { |
349 |
> |
for (nhits = 0, hwt = 0.0, sn = 0; sn < ncnts; |
350 |
> |
hwt += (double)source[scp->sno].nhits / |
351 |
> |
(double)source[scp->sno].ntests, |
352 |
> |
sn++) { |
353 |
|
/* check threshold */ |
354 |
|
if ((sn+nshadcheck>=ncnts ? cntord[sn].brt : |
355 |
|
cntord[sn].brt-cntord[sn+nshadcheck].brt) |
356 |
|
< ourthresh*bright(r->rcol)) |
357 |
|
break; |
358 |
+ |
scp = srccnt + cntord[sn].sndx; |
359 |
|
/* test for hit */ |
360 |
|
rayorigin(&sr, r, SHADOW, 1.0); |
361 |
< |
VCOPY(sr.rdir, srccnt[cntord[sn].sndx].dir); |
362 |
< |
sr.rsrc = srccnt[cntord[sn].sndx].sno; |
363 |
< |
source[sr.rsrc].ntests++; /* keep statistics */ |
361 |
> |
VCOPY(sr.rdir, scp->dir); |
362 |
> |
sr.rsrc = scp->sno; |
363 |
> |
/* keep statistics */ |
364 |
> |
if (source[scp->sno].ntests++ > 0xfffffff0) { |
365 |
> |
source[scp->sno].ntests >>= 1; |
366 |
> |
source[scp->sno].nhits >>= 1; |
367 |
> |
} |
368 |
|
if (localhit(&sr, &thescene) && |
369 |
< |
( sr.ro != source[sr.rsrc].so || |
370 |
< |
source[sr.rsrc].sflags & SFOLLOW )) { |
369 |
> |
( sr.ro != source[scp->sno].so || |
370 |
> |
source[scp->sno].sflags & SFOLLOW )) { |
371 |
|
/* follow entire path */ |
372 |
|
raycont(&sr); |
373 |
+ |
rayparticipate(&sr); |
374 |
|
if (trace != NULL) |
375 |
|
(*trace)(&sr); /* trace execution */ |
376 |
|
if (bright(sr.rcol) <= FTINY) |
377 |
|
continue; /* missed! */ |
378 |
< |
copycolor(srccnt[cntord[sn].sndx].val, sr.rcol); |
379 |
< |
multcolor(srccnt[cntord[sn].sndx].val, |
295 |
< |
srccnt[cntord[sn].sndx].coef); |
378 |
> |
copycolor(scp->val, sr.rcol); |
379 |
> |
multcolor(scp->val, scp->coef); |
380 |
|
} |
381 |
|
/* add contribution if hit */ |
382 |
< |
addcolor(r->rcol, srccnt[cntord[sn].sndx].val); |
382 |
> |
addcolor(r->rcol, scp->val); |
383 |
|
nhits++; |
384 |
< |
source[sr.rsrc].nhits++; |
384 |
> |
source[scp->sno].nhits++; |
385 |
|
} |
386 |
< |
/* surface hit rate */ |
387 |
< |
if (sn > 0) |
388 |
< |
hwt = (double)nhits / (double)sn; |
386 |
> |
/* source hit rate */ |
387 |
> |
if (hwt > FTINY) |
388 |
> |
hwt = (double)nhits / hwt; |
389 |
|
else |
390 |
|
hwt = 0.5; |
391 |
|
#ifdef DEBUG |
392 |
< |
sprintf(errmsg, "%d tested, %d untested, %f hit rate\n", |
392 |
> |
sprintf(errmsg, "%d tested, %d untested, %f conditional hit rate\n", |
393 |
|
sn, ncnts-sn, hwt); |
394 |
|
eputs(errmsg); |
395 |
|
#endif |
396 |
|
/* add in untested sources */ |
397 |
|
for ( ; sn < ncnts; sn++) { |
398 |
< |
sr.rsrc = srccnt[cntord[sn].sndx].sno; |
399 |
< |
prob = hwt * (double)source[sr.rsrc].nhits / |
400 |
< |
(double)source[sr.rsrc].ntests; |
401 |
< |
scalecolor(srccnt[cntord[sn].sndx].val, prob); |
402 |
< |
addcolor(r->rcol, srccnt[cntord[sn].sndx].val); |
398 |
> |
scp = srccnt + cntord[sn].sndx; |
399 |
> |
prob = hwt * (double)source[scp->sno].nhits / |
400 |
> |
(double)source[scp->sno].ntests; |
401 |
> |
if (prob > 1.0) |
402 |
> |
prob = 1.0; |
403 |
> |
scalecolor(scp->val, prob); |
404 |
> |
addcolor(r->rcol, scp->val); |
405 |
|
} |
406 |
+ |
} |
407 |
+ |
|
408 |
+ |
|
409 |
+ |
void |
410 |
+ |
srcscatter(r) /* compute source scattering into ray */ |
411 |
+ |
register RAY *r; |
412 |
+ |
{ |
413 |
+ |
int oldsampndx; |
414 |
+ |
int nsamps; |
415 |
+ |
RAY sr; |
416 |
+ |
SRCINDEX si; |
417 |
+ |
double t, d; |
418 |
+ |
double re, ge, be; |
419 |
+ |
COLOR cvext; |
420 |
+ |
int i, j; |
421 |
+ |
|
422 |
+ |
if (r->slights == NULL || r->slights[0] == 0 |
423 |
+ |
|| r->gecc >= 1.-FTINY || r->rot >= FHUGE) |
424 |
+ |
return; |
425 |
+ |
if (ssampdist <= FTINY || (nsamps = r->rot/ssampdist + .5) < 1) |
426 |
+ |
nsamps = 1; |
427 |
+ |
#if MAXSSAMP |
428 |
+ |
else if (nsamps > MAXSSAMP) |
429 |
+ |
nsamps = MAXSSAMP; |
430 |
+ |
#endif |
431 |
+ |
oldsampndx = samplendx; |
432 |
+ |
samplendx = random()&0x7fff; /* randomize */ |
433 |
+ |
for (i = r->slights[0]; i > 0; i--) { /* for each source */ |
434 |
+ |
for (j = 0; j < nsamps; j++) { /* for each sample position */ |
435 |
+ |
samplendx++; |
436 |
+ |
t = r->rot * (j+frandom())/nsamps; |
437 |
+ |
/* extinction */ |
438 |
+ |
re = t*colval(r->cext,RED); |
439 |
+ |
ge = t*colval(r->cext,GRN); |
440 |
+ |
be = t*colval(r->cext,BLU); |
441 |
+ |
setcolor(cvext, re > 92. ? 0. : exp(-re), |
442 |
+ |
ge > 92. ? 0. : exp(-ge), |
443 |
+ |
be > 92. ? 0. : exp(-be)); |
444 |
+ |
if (intens(cvext) <= FTINY) |
445 |
+ |
break; /* too far away */ |
446 |
+ |
sr.rorg[0] = r->rorg[0] + r->rdir[0]*t; |
447 |
+ |
sr.rorg[1] = r->rorg[1] + r->rdir[1]*t; |
448 |
+ |
sr.rorg[2] = r->rorg[2] + r->rdir[2]*t; |
449 |
+ |
sr.rmax = 0.; |
450 |
+ |
initsrcindex(&si); /* sample ray to this source */ |
451 |
+ |
si.sn = r->slights[i]; |
452 |
+ |
nopart(&si, &sr); |
453 |
+ |
if (!srcray(&sr, NULL, &si) || |
454 |
+ |
sr.rsrc != r->slights[i]) |
455 |
+ |
continue; /* no path */ |
456 |
+ |
copycolor(sr.cext, r->cext); |
457 |
+ |
copycolor(sr.albedo, r->albedo); |
458 |
+ |
sr.gecc = r->gecc; |
459 |
+ |
sr.slights = r->slights; |
460 |
+ |
rayvalue(&sr); /* eval. source ray */ |
461 |
+ |
if (bright(sr.rcol) <= FTINY) |
462 |
+ |
continue; |
463 |
+ |
if (r->gecc <= FTINY) /* compute P(theta) */ |
464 |
+ |
d = 1.; |
465 |
+ |
else { |
466 |
+ |
d = DOT(r->rdir, sr.rdir); |
467 |
+ |
d = 1. + r->gecc*r->gecc - 2.*r->gecc*d; |
468 |
+ |
d = (1. - r->gecc*r->gecc) / (d*sqrt(d)); |
469 |
+ |
} |
470 |
+ |
/* other factors */ |
471 |
+ |
d *= si.dom * r->rot / (4.*PI*nsamps); |
472 |
+ |
multcolor(sr.rcol, r->cext); |
473 |
+ |
multcolor(sr.rcol, r->albedo); |
474 |
+ |
scalecolor(sr.rcol, d); |
475 |
+ |
multcolor(sr.rcol, cvext); |
476 |
+ |
addcolor(r->rcol, sr.rcol); /* add it in */ |
477 |
+ |
} |
478 |
+ |
} |
479 |
+ |
samplendx = oldsampndx; |
480 |
+ |
} |
481 |
+ |
|
482 |
+ |
|
483 |
+ |
/**************************************************************** |
484 |
+ |
* The following macros were separated from the m_light() routine |
485 |
+ |
* because they are very nasty and difficult to understand. |
486 |
+ |
*/ |
487 |
+ |
|
488 |
+ |
/* illumblock * |
489 |
+ |
* |
490 |
+ |
* We cannot allow an illum to pass to another illum, because that |
491 |
+ |
* would almost certainly constitute overcounting. |
492 |
+ |
* However, we do allow an illum to pass to another illum |
493 |
+ |
* that is actually going to relay to a virtual light source. |
494 |
+ |
* We also prevent an illum from passing to a glow; this provides a |
495 |
+ |
* convenient mechanism for defining detailed light source |
496 |
+ |
* geometry behind (or inside) an effective radiator. |
497 |
+ |
*/ |
498 |
+ |
|
499 |
+ |
static int |
500 |
+ |
weaksrcmat(int obj) /* identify material */ |
501 |
+ |
{ |
502 |
+ |
register OBJREC *o = objptr(obj); |
503 |
+ |
|
504 |
+ |
while (!ismaterial(o->otype)) /* find material */ |
505 |
+ |
o = objptr(o->omod); |
506 |
+ |
return((o->otype==MAT_ILLUM)|(o->otype==MAT_GLOW)); |
507 |
+ |
} |
508 |
+ |
|
509 |
+ |
#define illumblock(m, r) (!(source[r->rsrc].sflags&SVIRTUAL) && \ |
510 |
+ |
r->rod > 0.0 && \ |
511 |
+ |
weaksrcmat(source[r->rsrc].so->omod)) |
512 |
+ |
|
513 |
+ |
/* wrongsource * |
514 |
+ |
* |
515 |
+ |
* This source is the wrong source (ie. overcounted) if we are |
516 |
+ |
* aimed to a different source than the one we hit and the one |
517 |
+ |
* we hit is not an illum that should be passed. |
518 |
+ |
*/ |
519 |
+ |
|
520 |
+ |
#define wrongsource(m, r) (r->rsrc>=0 && source[r->rsrc].so!=r->ro && \ |
521 |
+ |
(m->otype!=MAT_ILLUM || illumblock(m,r))) |
522 |
+ |
|
523 |
+ |
/* distglow * |
524 |
+ |
* |
525 |
+ |
* A distant glow is an object that sometimes acts as a light source, |
526 |
+ |
* but is too far away from the test point to be one in this case. |
527 |
+ |
* (Glows with negative radii should NEVER participate in illumination.) |
528 |
+ |
*/ |
529 |
+ |
|
530 |
+ |
#define distglow(m, r, d) (m->otype==MAT_GLOW && \ |
531 |
+ |
m->oargs.farg[3] >= -FTINY && \ |
532 |
+ |
d > m->oargs.farg[3]) |
533 |
+ |
|
534 |
+ |
/* badcomponent * |
535 |
+ |
* |
536 |
+ |
* We must avoid counting light sources in the ambient calculation, |
537 |
+ |
* since the direct component is handled separately. Therefore, any |
538 |
+ |
* ambient ray which hits an active light source must be discarded. |
539 |
+ |
* The same is true for stray specular samples, since the specular |
540 |
+ |
* contribution from light sources is calculated separately. |
541 |
+ |
*/ |
542 |
+ |
|
543 |
+ |
#define badcomponent(m, r) (r->crtype&(AMBIENT|SPECULAR) && \ |
544 |
+ |
!(r->crtype&SHADOW || r->rod < 0.0 || \ |
545 |
+ |
/* not 100% correct */ distglow(m, r, r->rot))) |
546 |
+ |
|
547 |
+ |
/* passillum * |
548 |
+ |
* |
549 |
+ |
* An illum passes to another material type when we didn't hit it |
550 |
+ |
* on purpose (as part of a direct calculation), or it is relaying |
551 |
+ |
* a virtual light source. |
552 |
+ |
*/ |
553 |
+ |
|
554 |
+ |
#define passillum(m, r) (m->otype==MAT_ILLUM && \ |
555 |
+ |
(r->rsrc<0 || source[r->rsrc].so!=r->ro || \ |
556 |
+ |
source[r->rsrc].sflags&SVIRTUAL)) |
557 |
+ |
|
558 |
+ |
/* srcignore * |
559 |
+ |
* |
560 |
+ |
* The -dv flag is normally on for sources to be visible. |
561 |
+ |
*/ |
562 |
+ |
|
563 |
+ |
#define srcignore(m, r) !(directvis || r->crtype&SHADOW || \ |
564 |
+ |
distglow(m, r, raydist(r,PRIMARY))) |
565 |
+ |
|
566 |
+ |
|
567 |
+ |
int |
568 |
+ |
m_light(m, r) /* ray hit a light source */ |
569 |
+ |
register OBJREC *m; |
570 |
+ |
register RAY *r; |
571 |
+ |
{ |
572 |
+ |
/* check for over-counting */ |
573 |
+ |
if (badcomponent(m, r)) |
574 |
+ |
return(1); |
575 |
+ |
if (wrongsource(m, r)) |
576 |
+ |
return(1); |
577 |
+ |
/* check for passed illum */ |
578 |
+ |
if (passillum(m, r)) { |
579 |
+ |
if (m->oargs.nsargs && strcmp(m->oargs.sarg[0], VOIDID)) |
580 |
+ |
return(rayshade(r,lastmod(objndx(m),m->oargs.sarg[0]))); |
581 |
+ |
raytrans(r); |
582 |
+ |
return(1); |
583 |
+ |
} |
584 |
+ |
/* otherwise treat as source */ |
585 |
+ |
/* check for behind */ |
586 |
+ |
if (r->rod < 0.0) |
587 |
+ |
return(1); |
588 |
+ |
/* check for invisibility */ |
589 |
+ |
if (srcignore(m, r)) |
590 |
+ |
return(1); |
591 |
+ |
/* check for outside spot */ |
592 |
+ |
if (m->otype==MAT_SPOT && spotout(r, makespot(m))) |
593 |
+ |
return(1); |
594 |
+ |
/* get distribution pattern */ |
595 |
+ |
raytexture(r, m->omod); |
596 |
+ |
/* get source color */ |
597 |
+ |
setcolor(r->rcol, m->oargs.farg[0], |
598 |
+ |
m->oargs.farg[1], |
599 |
+ |
m->oargs.farg[2]); |
600 |
+ |
/* modify value */ |
601 |
+ |
multcolor(r->rcol, r->pcol); |
602 |
+ |
return(1); |
603 |
|
} |