| 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 |
– |
* |
| 10 |
|
* 5/9/86 |
| 11 |
|
*/ |
| 12 |
|
|
| 39 |
|
|
| 40 |
|
static FILE *ambfp = NULL; /* ambient file pointer */ |
| 41 |
|
|
| 42 |
+ |
#define AMBFLUSH (BUFSIZ/AMBVALSIZ) |
| 43 |
+ |
|
| 44 |
|
#define newambval() (AMBVAL *)bmalloc(sizeof(AMBVAL)) |
| 45 |
|
|
| 46 |
|
#define newambtree() (AMBTREE *)calloc(8, sizeof(AMBTREE)) |
| 47 |
|
|
| 48 |
+ |
extern long ftell(), lseek(); |
| 49 |
+ |
static int initambfile(), avsave(), avinsert(), ambsync(); |
| 50 |
|
|
| 51 |
+ |
|
| 52 |
+ |
setambres(ar) /* set ambient resolution */ |
| 53 |
+ |
int ar; |
| 54 |
+ |
{ |
| 55 |
+ |
/* set min & max radii */ |
| 56 |
+ |
if (ar <= 0) { |
| 57 |
+ |
minarad = 0.0; |
| 58 |
+ |
maxarad = thescene.cusize / 2.0; |
| 59 |
+ |
} else { |
| 60 |
+ |
minarad = thescene.cusize / ar; |
| 61 |
+ |
maxarad = 16.0 * minarad; /* heuristic */ |
| 62 |
+ |
if (maxarad > thescene.cusize / 2.0) |
| 63 |
+ |
maxarad = thescene.cusize / 2.0; |
| 64 |
+ |
} |
| 65 |
+ |
if (maxarad <= FTINY) |
| 66 |
+ |
maxarad = .001; |
| 67 |
+ |
} |
| 68 |
+ |
|
| 69 |
+ |
|
| 70 |
|
setambient(afile) /* initialize calculation */ |
| 71 |
|
char *afile; |
| 72 |
|
{ |
| 73 |
< |
long ftell(); |
| 73 |
> |
long headlen; |
| 74 |
|
AMBVAL amb; |
| 75 |
< |
|
| 76 |
< |
maxarad = thescene.cusize / 2.0; /* maximum radius */ |
| 77 |
< |
/* minimum radius */ |
| 58 |
< |
minarad = ambres > 0 ? thescene.cusize/ambres : 0.0; |
| 59 |
< |
|
| 60 |
< |
/* open ambient file */ |
| 75 |
> |
/* init ambient limits */ |
| 76 |
> |
setambres(ambres); |
| 77 |
> |
/* open ambient file */ |
| 78 |
|
if (afile != NULL) |
| 79 |
|
if ((ambfp = fopen(afile, "r+")) != NULL) { |
| 80 |
< |
while (fread((char *)&amb,sizeof(AMBVAL),1,ambfp) == 1) |
| 80 |
> |
initambfile(0); |
| 81 |
> |
headlen = ftell(ambfp); |
| 82 |
> |
while (readambval(&amb, ambfp)) |
| 83 |
|
avinsert(&amb, &atrunk, thescene.cuorg, |
| 84 |
|
thescene.cusize); |
| 85 |
|
/* align */ |
| 86 |
< |
fseek(ambfp, -(ftell(ambfp)%sizeof(AMBVAL)), 1); |
| 87 |
< |
} else if ((ambfp = fopen(afile, "w")) == NULL) { |
| 86 |
> |
fseek(ambfp, -((ftell(ambfp)-headlen)%AMBVALSIZ), 1); |
| 87 |
> |
} else if ((ambfp = fopen(afile, "w+")) != NULL) |
| 88 |
> |
initambfile(1); |
| 89 |
> |
else { |
| 90 |
|
sprintf(errmsg, "cannot open ambient file \"%s\"", |
| 91 |
|
afile); |
| 92 |
|
error(SYSTEM, errmsg); |
| 121 |
|
register RAY *r; |
| 122 |
|
{ |
| 123 |
|
static int rdepth = 0; /* ambient recursion */ |
| 124 |
< |
double wsum; |
| 124 |
> |
double d; |
| 125 |
|
|
| 105 |
– |
rdepth++; /* increment level */ |
| 106 |
– |
|
| 126 |
|
if (ambdiv <= 0) /* no ambient calculation */ |
| 127 |
|
goto dumbamb; |
| 128 |
|
/* check number of bounces */ |
| 129 |
< |
if (rdepth > ambounce) |
| 129 |
> |
if (rdepth >= ambounce) |
| 130 |
|
goto dumbamb; |
| 131 |
|
/* check ambient list */ |
| 132 |
|
if (ambincl != -1 && r->ro != NULL && |
| 134 |
|
goto dumbamb; |
| 135 |
|
|
| 136 |
|
if (ambacc <= FTINY) { /* no ambient storage */ |
| 137 |
< |
if (doambient(acol, r, NULL, NULL) == 0.0) |
| 137 |
> |
rdepth++; |
| 138 |
> |
d = doambient(acol, r, r->rweight, NULL, NULL); |
| 139 |
> |
rdepth--; |
| 140 |
> |
if (d == 0.0) |
| 141 |
|
goto dumbamb; |
| 142 |
< |
goto done; |
| 142 |
> |
return; |
| 143 |
|
} |
| 144 |
|
/* get ambient value */ |
| 145 |
|
setcolor(acol, 0.0, 0.0, 0.0); |
| 146 |
< |
wsum = sumambient(acol, r, &atrunk, thescene.cuorg, thescene.cusize); |
| 147 |
< |
if (wsum > FTINY) |
| 148 |
< |
scalecolor(acol, 1.0/wsum); |
| 149 |
< |
else if (makeambient(acol, r) == 0.0) |
| 150 |
< |
goto dumbamb; |
| 151 |
< |
goto done; |
| 152 |
< |
|
| 146 |
> |
d = sumambient(acol, r, rdepth, |
| 147 |
> |
&atrunk, thescene.cuorg, thescene.cusize); |
| 148 |
> |
if (d > FTINY) |
| 149 |
> |
scalecolor(acol, 1.0/d); |
| 150 |
> |
else { |
| 151 |
> |
d = makeambient(acol, r, rdepth++); |
| 152 |
> |
rdepth--; |
| 153 |
> |
} |
| 154 |
> |
if (d > FTINY) |
| 155 |
> |
return; |
| 156 |
|
dumbamb: /* return global value */ |
| 157 |
|
copycolor(acol, ambval); |
| 133 |
– |
done: /* must finish here! */ |
| 134 |
– |
rdepth--; |
| 158 |
|
} |
| 159 |
|
|
| 160 |
|
|
| 161 |
|
double |
| 162 |
< |
sumambient(acol, r, at, c0, s) /* get interpolated ambient value */ |
| 162 |
> |
sumambient(acol, r, al, at, c0, s) /* get interpolated ambient value */ |
| 163 |
|
COLOR acol; |
| 164 |
|
register RAY *r; |
| 165 |
+ |
int al; |
| 166 |
|
AMBTREE *at; |
| 167 |
|
FVECT c0; |
| 168 |
|
double s; |
| 178 |
|
wsum = 0.0; |
| 179 |
|
for (av = at->alist; av != NULL; av = av->next) { |
| 180 |
|
/* |
| 181 |
< |
* Ray strength test. |
| 181 |
> |
* Ambient level test. |
| 182 |
|
*/ |
| 183 |
< |
if (av->lvl > r->rlvl || av->weight < r->rweight-FTINY) |
| 183 |
> |
if (av->lvl > al || av->weight < r->rweight-FTINY) |
| 184 |
|
continue; |
| 185 |
|
/* |
| 186 |
|
* Ambient radius test. |
| 207 |
|
for (j = 0; j < 3; j++) |
| 208 |
|
d += (r->rop[j] - av->pos[j]) * |
| 209 |
|
(av->dir[j] + r->ron[j]); |
| 210 |
< |
if (d*0.5 < -minarad*ambacc) |
| 210 |
> |
if (d*0.5 < -minarad*ambacc-.001) |
| 211 |
|
continue; |
| 212 |
|
/* |
| 213 |
|
* Jittering final test reduces image artifacts. |
| 214 |
|
*/ |
| 215 |
|
wt = sqrt(e1) + sqrt(e2); |
| 216 |
< |
wt *= .9 + .2*frandom(); |
| 216 |
> |
wt *= .9 + .2*urand(9015+samplendx); |
| 217 |
|
if (wt > ambacc) |
| 218 |
|
continue; |
| 219 |
|
if (wt <= 1e-3) |
| 221 |
|
else |
| 222 |
|
wt = 1.0 / wt; |
| 223 |
|
wsum += wt; |
| 224 |
< |
copycolor(ct, av->val); |
| 224 |
> |
extambient(ct, av, r->rop, r->ron); |
| 225 |
|
scalecolor(ct, wt); |
| 226 |
|
addcolor(acol, ct); |
| 227 |
|
} |
| 240 |
|
break; |
| 241 |
|
} |
| 242 |
|
if (j == 3) |
| 243 |
< |
wsum += sumambient(acol, r, at->kid+i, ck0, s); |
| 243 |
> |
wsum += sumambient(acol, r, al, at->kid+i, ck0, s); |
| 244 |
|
} |
| 245 |
|
return(wsum); |
| 246 |
|
} |
| 247 |
|
|
| 248 |
|
|
| 249 |
|
double |
| 250 |
< |
makeambient(acol, r) /* make a new ambient value */ |
| 250 |
> |
makeambient(acol, r, al) /* make a new ambient value */ |
| 251 |
|
COLOR acol; |
| 252 |
|
register RAY *r; |
| 253 |
+ |
int al; |
| 254 |
|
{ |
| 255 |
|
AMBVAL amb; |
| 256 |
|
FVECT gp, gd; |
| 257 |
< |
|
| 258 |
< |
amb.rad = doambient(acol, r, gp, gd); /* compute ambient */ |
| 257 |
> |
/* compute weight */ |
| 258 |
> |
amb.weight = pow(AVGREFL, (double)al); |
| 259 |
> |
if (r->rweight < 0.2*amb.weight) /* heuristic */ |
| 260 |
> |
amb.weight = r->rweight; |
| 261 |
> |
/* compute ambient */ |
| 262 |
> |
amb.rad = doambient(acol, r, amb.weight, gp, gd); |
| 263 |
|
if (amb.rad == 0.0) |
| 264 |
|
return(0.0); |
| 265 |
|
/* store it */ |
| 266 |
|
VCOPY(amb.pos, r->rop); |
| 267 |
|
VCOPY(amb.dir, r->ron); |
| 268 |
< |
amb.lvl = r->rlvl; |
| 240 |
< |
amb.weight = r->rweight; |
| 268 |
> |
amb.lvl = al; |
| 269 |
|
copycolor(amb.val, acol); |
| 270 |
|
VCOPY(amb.gpos, gp); |
| 271 |
|
VCOPY(amb.gdir, gd); |
| 272 |
|
/* insert into tree */ |
| 273 |
< |
avinsert(&amb, &atrunk, thescene.cuorg, thescene.cusize); |
| 246 |
< |
avsave(&amb); /* write to file */ |
| 273 |
> |
avsave(&amb); /* and save to file */ |
| 274 |
|
return(amb.rad); |
| 275 |
|
} |
| 276 |
|
|
| 277 |
|
|
| 278 |
+ |
extambient(cr, ap, pv, nv) /* extrapolate value at pv, nv */ |
| 279 |
+ |
COLOR cr; |
| 280 |
+ |
register AMBVAL *ap; |
| 281 |
+ |
FVECT pv, nv; |
| 282 |
+ |
{ |
| 283 |
+ |
FVECT v1, v2; |
| 284 |
+ |
register int i; |
| 285 |
+ |
double d; |
| 286 |
+ |
|
| 287 |
+ |
d = 1.0; /* zeroeth order */ |
| 288 |
+ |
/* gradient due to translation */ |
| 289 |
+ |
for (i = 0; i < 3; i++) |
| 290 |
+ |
d += ap->gpos[i]*(pv[i]-ap->pos[i]); |
| 291 |
+ |
/* gradient due to rotation */ |
| 292 |
+ |
VCOPY(v1, ap->dir); |
| 293 |
+ |
fcross(v2, v1, nv); |
| 294 |
+ |
d += DOT(ap->gdir, v2); |
| 295 |
+ |
if (d <= 0.0) { |
| 296 |
+ |
setcolor(cr, 0.0, 0.0, 0.0); |
| 297 |
+ |
return; |
| 298 |
+ |
} |
| 299 |
+ |
copycolor(cr, ap->val); |
| 300 |
+ |
scalecolor(cr, d); |
| 301 |
+ |
} |
| 302 |
+ |
|
| 303 |
+ |
|
| 304 |
|
static |
| 305 |
< |
avsave(av) /* save an ambient value */ |
| 305 |
> |
initambfile(creat) /* initialize ambient file */ |
| 306 |
> |
int creat; |
| 307 |
> |
{ |
| 308 |
> |
extern char *progname, *octname, VersionID[]; |
| 309 |
> |
|
| 310 |
> |
setbuf(ambfp, bmalloc(BUFSIZ)); |
| 311 |
> |
if (creat) { /* new file */ |
| 312 |
> |
fprintf(ambfp, "%s -av %g %g %g -ab %d -aa %g ", |
| 313 |
> |
progname, colval(ambval,RED), |
| 314 |
> |
colval(ambval,GRN), colval(ambval,BLU), |
| 315 |
> |
ambounce, ambacc); |
| 316 |
> |
fprintf(ambfp, "-ad %d -as %d -ar %d %s\n", |
| 317 |
> |
ambdiv, ambssamp, ambres, |
| 318 |
> |
octname==NULL ? "" : octname); |
| 319 |
> |
fprintf(ambfp, "SOFTWARE= %s\n", VersionID); |
| 320 |
> |
fputformat(AMBFMT, ambfp); |
| 321 |
> |
putc('\n', ambfp); |
| 322 |
> |
putambmagic(ambfp); |
| 323 |
> |
fflush(ambfp); |
| 324 |
> |
#ifndef NIX |
| 325 |
> |
sync(); /* protect against NFS buffering */ |
| 326 |
> |
#endif |
| 327 |
> |
} else if (checkheader(ambfp, AMBFMT, NULL) < 0 || !hasambmagic(ambfp)) |
| 328 |
> |
error(USER, "bad ambient file"); |
| 329 |
> |
} |
| 330 |
> |
|
| 331 |
> |
|
| 332 |
> |
static |
| 333 |
> |
avsave(av) /* insert and save an ambient value */ |
| 334 |
|
AMBVAL *av; |
| 335 |
|
{ |
| 255 |
– |
#ifdef AMBFLUSH |
| 336 |
|
static int nunflshed = 0; |
| 337 |
< |
#endif |
| 337 |
> |
|
| 338 |
> |
avinsert(av, &atrunk, thescene.cuorg, thescene.cusize); |
| 339 |
|
if (ambfp == NULL) |
| 340 |
|
return; |
| 341 |
< |
if (fwrite((char *)av, sizeof(AMBVAL), 1, ambfp) != 1) |
| 341 |
> |
if (writambval(av, ambfp) < 0) |
| 342 |
|
goto writerr; |
| 262 |
– |
#ifdef AMBFLUSH |
| 343 |
|
if (++nunflshed >= AMBFLUSH) { |
| 344 |
< |
if (fflush(ambfp) == EOF) |
| 344 |
> |
if (ambsync() == EOF) |
| 345 |
|
goto writerr; |
| 346 |
|
nunflshed = 0; |
| 347 |
|
} |
| 268 |
– |
#endif |
| 348 |
|
return; |
| 349 |
|
writerr: |
| 350 |
|
error(SYSTEM, "error writing ambient file"); |
| 386 |
|
memerr: |
| 387 |
|
error(SYSTEM, "out of memory in avinsert"); |
| 388 |
|
} |
| 389 |
+ |
|
| 390 |
+ |
|
| 391 |
+ |
#ifdef NIX |
| 392 |
+ |
|
| 393 |
+ |
static |
| 394 |
+ |
ambsync() /* flush ambient file */ |
| 395 |
+ |
{ |
| 396 |
+ |
return(fflush(ambfp)); |
| 397 |
+ |
} |
| 398 |
+ |
|
| 399 |
+ |
#else |
| 400 |
+ |
|
| 401 |
+ |
#include <fcntl.h> |
| 402 |
+ |
#include <sys/types.h> |
| 403 |
+ |
#include <sys/stat.h> |
| 404 |
+ |
|
| 405 |
+ |
static |
| 406 |
+ |
ambsync() /* synchronize ambient file */ |
| 407 |
+ |
{ |
| 408 |
+ |
static FILE *ambinp = NULL; |
| 409 |
+ |
struct flock fls; |
| 410 |
+ |
struct stat sts; |
| 411 |
+ |
AMBVAL avs; |
| 412 |
+ |
long lastpos, flen; |
| 413 |
+ |
register int n; |
| 414 |
+ |
/* gain exclusive access */ |
| 415 |
+ |
fls.l_type = F_WRLCK; |
| 416 |
+ |
fls.l_whence = 0; |
| 417 |
+ |
fls.l_start = 0L; |
| 418 |
+ |
fls.l_len = 0L; |
| 419 |
+ |
if (fcntl(fileno(ambfp), F_SETLKW, &fls) < 0) |
| 420 |
+ |
error(SYSTEM, "cannot lock ambient file"); |
| 421 |
+ |
/* see if file has grown */ |
| 422 |
+ |
lastpos = lseek(fileno(ambfp), 0L, 1); /* get previous position */ |
| 423 |
+ |
if (fstat(fileno(ambfp), &sts) < 0) /* get current length */ |
| 424 |
+ |
error(SYSTEM, "cannot stat ambient file"); |
| 425 |
+ |
flen = sts.st_size; |
| 426 |
+ |
if (n = (flen - lastpos)/AMBVALSIZ) { /* file has grown */ |
| 427 |
+ |
if (ambinp == NULL) /* use duplicate file */ |
| 428 |
+ |
ambinp = fdopen(dup(fileno(ambfp)), "r"); |
| 429 |
+ |
while (n--) { /* load contributed values */ |
| 430 |
+ |
readambval(&avs, ambinp); |
| 431 |
+ |
avinsert(&avs,&atrunk,thescene.cuorg,thescene.cusize); |
| 432 |
+ |
} /* moves shared file pointer */ |
| 433 |
+ |
if (n = (flen - lastpos)%AMBVALSIZ) /* alignment */ |
| 434 |
+ |
lseek(fileno(ambfp), flen-n, 0); |
| 435 |
+ |
} |
| 436 |
+ |
n = fflush(ambfp); /* calls write() at last */ |
| 437 |
+ |
fls.l_type = F_UNLCK; /* release file */ |
| 438 |
+ |
fcntl(fileno(ambfp), F_SETLKW, &fls); |
| 439 |
+ |
return(n); |
| 440 |
+ |
} |
| 441 |
+ |
|
| 442 |
+ |
#endif |
