1 |
greg |
1.14 |
/* Copyright (c) 1991 Regents of the University of California */ |
2 |
greg |
1.1 |
|
3 |
|
|
#ifndef lint |
4 |
|
|
static char SCCSid[] = "$SunId$ LBL"; |
5 |
|
|
#endif |
6 |
|
|
|
7 |
|
|
/* |
8 |
|
|
* ambient.c - routines dealing with ambient (inter-reflected) component. |
9 |
|
|
* |
10 |
|
|
* The macro AMBFLUSH (if defined) is the number of ambient values |
11 |
|
|
* to wait before flushing to the ambient file. |
12 |
|
|
* |
13 |
|
|
* 5/9/86 |
14 |
|
|
*/ |
15 |
|
|
|
16 |
|
|
#include "ray.h" |
17 |
|
|
|
18 |
|
|
#include "octree.h" |
19 |
|
|
|
20 |
greg |
1.8 |
#include "otypes.h" |
21 |
|
|
|
22 |
greg |
1.14 |
#include "ambient.h" |
23 |
|
|
|
24 |
greg |
1.1 |
#include "random.h" |
25 |
|
|
|
26 |
|
|
#define OCTSCALE 0.5 /* ceil((valid rad.)/(cube size)) */ |
27 |
|
|
|
28 |
greg |
1.14 |
typedef struct ambtree { |
29 |
|
|
AMBVAL *alist; /* ambient value list */ |
30 |
|
|
struct ambtree *kid; /* 8 child nodes */ |
31 |
|
|
} AMBTREE; /* ambient octree */ |
32 |
|
|
|
33 |
greg |
1.1 |
extern CUBE thescene; /* contains space boundaries */ |
34 |
|
|
|
35 |
greg |
1.11 |
#define MAXASET 511 /* maximum number of elements in ambient set */ |
36 |
|
|
OBJECT ambset[MAXASET+1]={0}; /* ambient include/exclude set */ |
37 |
greg |
1.1 |
|
38 |
|
|
double maxarad; /* maximum ambient radius */ |
39 |
|
|
double minarad; /* minimum ambient radius */ |
40 |
|
|
|
41 |
|
|
static AMBTREE atrunk; /* our ambient trunk node */ |
42 |
|
|
|
43 |
|
|
static FILE *ambfp = NULL; /* ambient file pointer */ |
44 |
|
|
|
45 |
|
|
#define newambval() (AMBVAL *)bmalloc(sizeof(AMBVAL)) |
46 |
|
|
|
47 |
|
|
#define newambtree() (AMBTREE *)calloc(8, sizeof(AMBTREE)) |
48 |
|
|
|
49 |
|
|
|
50 |
greg |
2.3 |
setambres(ar) /* set ambient resolution */ |
51 |
|
|
int ar; |
52 |
|
|
{ |
53 |
|
|
/* set min & max radii */ |
54 |
|
|
if (ar <= 0) { |
55 |
|
|
minarad = 0.0; |
56 |
|
|
maxarad = thescene.cusize / 2.0; |
57 |
|
|
} else { |
58 |
|
|
minarad = thescene.cusize / ar; |
59 |
|
|
maxarad = 16.0 * minarad; /* heuristic */ |
60 |
|
|
if (maxarad > thescene.cusize / 2.0) |
61 |
|
|
maxarad = thescene.cusize / 2.0; |
62 |
|
|
} |
63 |
greg |
2.4 |
if (maxarad <= FTINY) |
64 |
|
|
maxarad = .001; |
65 |
greg |
2.3 |
} |
66 |
|
|
|
67 |
|
|
|
68 |
greg |
1.1 |
setambient(afile) /* initialize calculation */ |
69 |
|
|
char *afile; |
70 |
|
|
{ |
71 |
|
|
long ftell(); |
72 |
|
|
AMBVAL amb; |
73 |
greg |
2.3 |
/* init ambient limits */ |
74 |
|
|
setambres(ambres); |
75 |
|
|
/* open ambient file */ |
76 |
greg |
1.1 |
if (afile != NULL) |
77 |
|
|
if ((ambfp = fopen(afile, "r+")) != NULL) { |
78 |
greg |
2.5 |
while (readambval(&amb, ambfp)) |
79 |
greg |
1.1 |
avinsert(&amb, &atrunk, thescene.cuorg, |
80 |
|
|
thescene.cusize); |
81 |
|
|
/* align */ |
82 |
greg |
2.5 |
fseek(ambfp, -(ftell(ambfp)%AMBVALSIZ), 1); |
83 |
greg |
1.1 |
} else if ((ambfp = fopen(afile, "w")) == NULL) { |
84 |
|
|
sprintf(errmsg, "cannot open ambient file \"%s\"", |
85 |
|
|
afile); |
86 |
|
|
error(SYSTEM, errmsg); |
87 |
greg |
1.8 |
} |
88 |
|
|
} |
89 |
|
|
|
90 |
|
|
|
91 |
|
|
ambnotify(obj) /* record new modifier */ |
92 |
|
|
OBJECT obj; |
93 |
|
|
{ |
94 |
greg |
1.11 |
static int hitlimit = 0; |
95 |
greg |
1.8 |
register OBJREC *o = objptr(obj); |
96 |
|
|
register char **amblp; |
97 |
|
|
|
98 |
greg |
1.11 |
if (hitlimit || !ismodifier(o->otype)) |
99 |
greg |
1.8 |
return; |
100 |
|
|
for (amblp = amblist; *amblp != NULL; amblp++) |
101 |
|
|
if (!strcmp(o->oname, *amblp)) { |
102 |
greg |
1.11 |
if (ambset[0] >= MAXASET) { |
103 |
|
|
error(WARNING, "too many modifiers in ambient list"); |
104 |
|
|
hitlimit++; |
105 |
|
|
return; /* should this be fatal? */ |
106 |
|
|
} |
107 |
greg |
1.8 |
insertelem(ambset, obj); |
108 |
|
|
return; |
109 |
greg |
1.1 |
} |
110 |
|
|
} |
111 |
|
|
|
112 |
|
|
|
113 |
|
|
ambient(acol, r) /* compute ambient component for ray */ |
114 |
|
|
COLOR acol; |
115 |
|
|
register RAY *r; |
116 |
|
|
{ |
117 |
|
|
static int rdepth = 0; /* ambient recursion */ |
118 |
greg |
1.16 |
double d; |
119 |
greg |
1.1 |
|
120 |
|
|
if (ambdiv <= 0) /* no ambient calculation */ |
121 |
|
|
goto dumbamb; |
122 |
|
|
/* check number of bounces */ |
123 |
greg |
1.16 |
if (rdepth >= ambounce) |
124 |
greg |
1.1 |
goto dumbamb; |
125 |
|
|
/* check ambient list */ |
126 |
|
|
if (ambincl != -1 && r->ro != NULL && |
127 |
|
|
ambincl != inset(ambset, r->ro->omod)) |
128 |
|
|
goto dumbamb; |
129 |
|
|
|
130 |
|
|
if (ambacc <= FTINY) { /* no ambient storage */ |
131 |
greg |
1.16 |
rdepth++; |
132 |
|
|
d = doambient(acol, r, r->rweight, NULL, NULL); |
133 |
|
|
rdepth--; |
134 |
|
|
if (d == 0.0) |
135 |
greg |
1.1 |
goto dumbamb; |
136 |
greg |
1.16 |
return; |
137 |
greg |
1.1 |
} |
138 |
|
|
/* get ambient value */ |
139 |
|
|
setcolor(acol, 0.0, 0.0, 0.0); |
140 |
greg |
1.16 |
d = sumambient(acol, r, rdepth, |
141 |
|
|
&atrunk, thescene.cuorg, thescene.cusize); |
142 |
|
|
if (d > FTINY) |
143 |
|
|
scalecolor(acol, 1.0/d); |
144 |
|
|
else { |
145 |
|
|
d = makeambient(acol, r, rdepth++); |
146 |
|
|
rdepth--; |
147 |
|
|
} |
148 |
|
|
if (d > FTINY) |
149 |
|
|
return; |
150 |
greg |
1.1 |
dumbamb: /* return global value */ |
151 |
|
|
copycolor(acol, ambval); |
152 |
|
|
} |
153 |
|
|
|
154 |
|
|
|
155 |
|
|
double |
156 |
greg |
1.16 |
sumambient(acol, r, al, at, c0, s) /* get interpolated ambient value */ |
157 |
greg |
1.1 |
COLOR acol; |
158 |
|
|
register RAY *r; |
159 |
greg |
1.16 |
int al; |
160 |
greg |
1.1 |
AMBTREE *at; |
161 |
|
|
FVECT c0; |
162 |
|
|
double s; |
163 |
|
|
{ |
164 |
|
|
extern double sqrt(); |
165 |
|
|
double d, e1, e2, wt, wsum; |
166 |
|
|
COLOR ct; |
167 |
|
|
FVECT ck0; |
168 |
|
|
int i; |
169 |
|
|
register int j; |
170 |
|
|
register AMBVAL *av; |
171 |
greg |
1.7 |
/* do this node */ |
172 |
greg |
1.1 |
wsum = 0.0; |
173 |
|
|
for (av = at->alist; av != NULL; av = av->next) { |
174 |
|
|
/* |
175 |
greg |
1.16 |
* Ambient level test. |
176 |
greg |
1.1 |
*/ |
177 |
greg |
1.16 |
if (av->lvl > al || av->weight < r->rweight-FTINY) |
178 |
greg |
1.1 |
continue; |
179 |
|
|
/* |
180 |
|
|
* Ambient radius test. |
181 |
|
|
*/ |
182 |
|
|
e1 = 0.0; |
183 |
|
|
for (j = 0; j < 3; j++) { |
184 |
|
|
d = av->pos[j] - r->rop[j]; |
185 |
|
|
e1 += d * d; |
186 |
|
|
} |
187 |
|
|
e1 /= av->rad * av->rad; |
188 |
|
|
if (e1 > ambacc*ambacc*1.21) |
189 |
|
|
continue; |
190 |
|
|
/* |
191 |
|
|
* Normal direction test. |
192 |
|
|
*/ |
193 |
|
|
e2 = (1.0 - DOT(av->dir, r->ron)) * r->rweight; |
194 |
|
|
if (e2 < 0.0) e2 = 0.0; |
195 |
|
|
if (e1 + e2 > ambacc*ambacc*1.21) |
196 |
|
|
continue; |
197 |
|
|
/* |
198 |
|
|
* Ray behind test. |
199 |
|
|
*/ |
200 |
|
|
d = 0.0; |
201 |
|
|
for (j = 0; j < 3; j++) |
202 |
|
|
d += (r->rop[j] - av->pos[j]) * |
203 |
|
|
(av->dir[j] + r->ron[j]); |
204 |
greg |
1.18 |
if (d*0.5 < -minarad*ambacc-.001) |
205 |
greg |
1.1 |
continue; |
206 |
|
|
/* |
207 |
|
|
* Jittering final test reduces image artifacts. |
208 |
|
|
*/ |
209 |
|
|
wt = sqrt(e1) + sqrt(e2); |
210 |
greg |
2.2 |
wt *= .9 + .2*urand(9015+samplendx); |
211 |
greg |
1.6 |
if (wt > ambacc) |
212 |
greg |
1.1 |
continue; |
213 |
|
|
if (wt <= 1e-3) |
214 |
|
|
wt = 1e3; |
215 |
|
|
else |
216 |
|
|
wt = 1.0 / wt; |
217 |
|
|
wsum += wt; |
218 |
greg |
1.15 |
extambient(ct, av, r->rop, r->ron); |
219 |
greg |
1.1 |
scalecolor(ct, wt); |
220 |
|
|
addcolor(acol, ct); |
221 |
greg |
1.7 |
} |
222 |
|
|
if (at->kid == NULL) |
223 |
|
|
return(wsum); |
224 |
|
|
/* do children */ |
225 |
|
|
s *= 0.5; |
226 |
|
|
for (i = 0; i < 8; i++) { |
227 |
|
|
for (j = 0; j < 3; j++) { |
228 |
|
|
ck0[j] = c0[j]; |
229 |
|
|
if (1<<j & i) |
230 |
|
|
ck0[j] += s; |
231 |
|
|
if (r->rop[j] < ck0[j] - OCTSCALE*s) |
232 |
|
|
break; |
233 |
|
|
if (r->rop[j] > ck0[j] + (1.0+OCTSCALE)*s) |
234 |
|
|
break; |
235 |
|
|
} |
236 |
|
|
if (j == 3) |
237 |
greg |
1.16 |
wsum += sumambient(acol, r, al, at->kid+i, ck0, s); |
238 |
greg |
1.1 |
} |
239 |
|
|
return(wsum); |
240 |
|
|
} |
241 |
|
|
|
242 |
|
|
|
243 |
|
|
double |
244 |
greg |
1.16 |
makeambient(acol, r, al) /* make a new ambient value */ |
245 |
greg |
1.1 |
COLOR acol; |
246 |
|
|
register RAY *r; |
247 |
greg |
1.16 |
int al; |
248 |
greg |
1.1 |
{ |
249 |
|
|
AMBVAL amb; |
250 |
greg |
1.14 |
FVECT gp, gd; |
251 |
greg |
1.16 |
/* compute weight */ |
252 |
|
|
amb.weight = pow(AVGREFL, (double)al); |
253 |
greg |
1.17 |
if (r->rweight < 0.2*amb.weight) /* heuristic */ |
254 |
greg |
1.16 |
amb.weight = r->rweight; |
255 |
|
|
/* compute ambient */ |
256 |
|
|
amb.rad = doambient(acol, r, amb.weight, gp, gd); |
257 |
greg |
1.1 |
if (amb.rad == 0.0) |
258 |
|
|
return(0.0); |
259 |
|
|
/* store it */ |
260 |
|
|
VCOPY(amb.pos, r->rop); |
261 |
|
|
VCOPY(amb.dir, r->ron); |
262 |
greg |
1.16 |
amb.lvl = al; |
263 |
greg |
1.1 |
copycolor(amb.val, acol); |
264 |
greg |
1.14 |
VCOPY(amb.gpos, gp); |
265 |
|
|
VCOPY(amb.gdir, gd); |
266 |
greg |
1.1 |
/* insert into tree */ |
267 |
|
|
avinsert(&amb, &atrunk, thescene.cuorg, thescene.cusize); |
268 |
|
|
avsave(&amb); /* write to file */ |
269 |
|
|
return(amb.rad); |
270 |
greg |
1.15 |
} |
271 |
|
|
|
272 |
|
|
|
273 |
|
|
extambient(cr, ap, pv, nv) /* extrapolate value at pv, nv */ |
274 |
|
|
COLOR cr; |
275 |
|
|
register AMBVAL *ap; |
276 |
|
|
FVECT pv, nv; |
277 |
|
|
{ |
278 |
|
|
FVECT v1, v2; |
279 |
|
|
register int i; |
280 |
|
|
double d; |
281 |
|
|
|
282 |
|
|
d = 1.0; /* zeroeth order */ |
283 |
|
|
/* gradient due to translation */ |
284 |
|
|
for (i = 0; i < 3; i++) |
285 |
|
|
d += ap->gpos[i]*(pv[i]-ap->pos[i]); |
286 |
|
|
/* gradient due to rotation */ |
287 |
|
|
VCOPY(v1, ap->dir); |
288 |
|
|
fcross(v2, v1, nv); |
289 |
|
|
d += DOT(ap->gdir, v2); |
290 |
|
|
if (d <= 0.0) { |
291 |
|
|
setcolor(cr, 0.0, 0.0, 0.0); |
292 |
|
|
return; |
293 |
|
|
} |
294 |
|
|
copycolor(cr, ap->val); |
295 |
|
|
scalecolor(cr, d); |
296 |
greg |
1.1 |
} |
297 |
|
|
|
298 |
|
|
|
299 |
|
|
static |
300 |
|
|
avsave(av) /* save an ambient value */ |
301 |
|
|
AMBVAL *av; |
302 |
|
|
{ |
303 |
|
|
#ifdef AMBFLUSH |
304 |
|
|
static int nunflshed = 0; |
305 |
|
|
#endif |
306 |
|
|
if (ambfp == NULL) |
307 |
|
|
return; |
308 |
greg |
2.5 |
if (writambval(av, ambfp) < 0) |
309 |
greg |
1.1 |
goto writerr; |
310 |
|
|
#ifdef AMBFLUSH |
311 |
|
|
if (++nunflshed >= AMBFLUSH) { |
312 |
|
|
if (fflush(ambfp) == EOF) |
313 |
|
|
goto writerr; |
314 |
|
|
nunflshed = 0; |
315 |
|
|
} |
316 |
|
|
#endif |
317 |
|
|
return; |
318 |
|
|
writerr: |
319 |
|
|
error(SYSTEM, "error writing ambient file"); |
320 |
|
|
} |
321 |
|
|
|
322 |
|
|
|
323 |
|
|
static |
324 |
|
|
avinsert(aval, at, c0, s) /* insert ambient value in a tree */ |
325 |
|
|
AMBVAL *aval; |
326 |
|
|
register AMBTREE *at; |
327 |
|
|
FVECT c0; |
328 |
|
|
double s; |
329 |
|
|
{ |
330 |
|
|
FVECT ck0; |
331 |
|
|
int branch; |
332 |
|
|
register AMBVAL *av; |
333 |
|
|
register int i; |
334 |
|
|
|
335 |
|
|
if ((av = newambval()) == NULL) |
336 |
|
|
goto memerr; |
337 |
greg |
1.9 |
copystruct(av, aval); |
338 |
greg |
1.1 |
VCOPY(ck0, c0); |
339 |
|
|
while (s*(OCTSCALE/2) > av->rad*ambacc) { |
340 |
|
|
if (at->kid == NULL) |
341 |
|
|
if ((at->kid = newambtree()) == NULL) |
342 |
|
|
goto memerr; |
343 |
|
|
s *= 0.5; |
344 |
|
|
branch = 0; |
345 |
|
|
for (i = 0; i < 3; i++) |
346 |
|
|
if (av->pos[i] > ck0[i] + s) { |
347 |
|
|
ck0[i] += s; |
348 |
|
|
branch |= 1 << i; |
349 |
|
|
} |
350 |
|
|
at = at->kid + branch; |
351 |
|
|
} |
352 |
|
|
av->next = at->alist; |
353 |
|
|
at->alist = av; |
354 |
|
|
return; |
355 |
|
|
memerr: |
356 |
|
|
error(SYSTEM, "out of memory in avinsert"); |
357 |
|
|
} |