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root/radiance/ray/src/rt/ambient.c
Revision: 2.27
Committed: Sat Apr 29 10:51:28 1995 UTC (29 years ago) by greg
Content type: text/plain
Branch: MAIN
Changes since 2.26: +63 -29 lines
Log Message:
minor improvements

File Contents

# Content
1 /* Copyright (c) 1995 Regents of the University of California */
2
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
11 #include "ray.h"
12
13 #include "octree.h"
14
15 #include "otypes.h"
16
17 #include "ambient.h"
18
19 #include "random.h"
20
21 #define OCTSCALE 0.5 /* ceil((valid rad.)/(cube size)) */
22
23 typedef struct ambtree {
24 AMBVAL *alist; /* ambient value list */
25 struct ambtree *kid; /* 8 child nodes */
26 } AMBTREE; /* ambient octree */
27
28 extern CUBE thescene; /* contains space boundaries */
29
30 extern char *shm_boundary; /* memory sharing boundary */
31
32 #define MAXASET 511 /* maximum number of elements in ambient set */
33 OBJECT ambset[MAXASET+1]={0}; /* ambient include/exclude set */
34
35 double maxarad; /* maximum ambient radius */
36 double minarad; /* minimum ambient radius */
37
38 static AMBTREE atrunk; /* our ambient trunk node */
39
40 static FILE *ambfp = NULL; /* ambient file pointer */
41 static int nunflshed = 0; /* number of unflushed ambient values */
42
43 #ifndef SORT_THRESH
44 #ifdef BIGMEM
45 #define SORT_THRESH ((9L<<20)/sizeof(AMBVAL))
46 #else
47 #define SORT_THRESH ((3L<<20)/sizeof(AMBVAL))
48 #endif
49 #endif
50 #ifndef SORT_INTVL
51 #define SORT_INTVL (SORT_THRESH*8)
52 #endif
53
54 static unsigned long ambclock = 0; /* ambient access clock */
55 static unsigned int nambvals = 0; /* number of stored ambient values */
56 static unsigned long lastsort = 0; /* time of last value sort */
57 static long sortintvl = SORT_INTVL; /* time until next sort */
58
59 #define MAXACLOCK (1L<<30) /* clock turnover value */
60 /*
61 * Track access times unless we are sharing ambient values
62 * through memory on a multiprocessor, when we want to avoid
63 * claiming our own memory (copy on write).
64 */
65 #define tracktime (shm_boundary == NULL || ambfp == NULL)
66 #define checksort() if (ambclock > lastsort+sortintvl && \
67 nambvals > SORT_THRESH) sortambvals(0)
68
69 #define AMBFLUSH (BUFSIZ/AMBVALSIZ)
70
71 #define newambval() (AMBVAL *)bmalloc(sizeof(AMBVAL))
72
73 extern long ftell(), lseek();
74 static int initambfile(), avsave(), avinsert(), sortambvals();
75 static AMBVAL *avstore();
76 #ifdef F_SETLKW
77 static aflock();
78 #endif
79
80
81 setambres(ar) /* set ambient resolution */
82 int ar;
83 {
84 ambres = ar < 0 ? 0 : ar; /* may be done already */
85 /* set min & max radii */
86 if (ar <= 0) {
87 minarad = 0;
88 maxarad = thescene.cusize / 2.0;
89 } else {
90 minarad = thescene.cusize / ar;
91 maxarad = 16 * minarad; /* heuristic */
92 if (maxarad > thescene.cusize / 2.0)
93 maxarad = thescene.cusize / 2.0;
94 }
95 if (minarad <= FTINY)
96 minarad = 10*FTINY;
97 if (maxarad <= minarad)
98 maxarad = 64 * minarad;
99 }
100
101
102 setambacc(newa) /* set ambient accuracy */
103 double newa;
104 {
105 static double oldambacc = -1.0;
106
107 ambacc = newa < 0.0 ? 0.0 : newa; /* may be done already */
108 if (oldambacc < -FTINY)
109 oldambacc = ambacc; /* do nothing first call */
110 if (fabs(newa - oldambacc) < 0.01)
111 return; /* insignificant -- don't bother */
112 if (ambacc <= FTINY)
113 return; /* cannot build new tree */
114 /* else need to rebuild tree */
115 sortambvals(1);
116 oldambacc = ambacc; /* remeber setting for next call */
117 }
118
119
120 setambient(afile) /* initialize calculation */
121 char *afile;
122 {
123 long headlen;
124 AMBVAL amb;
125 /* init ambient limits */
126 setambres(ambres);
127 setambacc(ambacc);
128 if (afile == NULL)
129 return;
130 if (ambacc <= FTINY) {
131 sprintf(errmsg, "zero ambient accuracy so \"%s\" not opened",
132 afile);
133 error(WARNING, errmsg);
134 return;
135 }
136 /* open ambient file */
137 if ((ambfp = fopen(afile, "r+")) != NULL) {
138 initambfile(0);
139 headlen = ftell(ambfp);
140 while (readambval(&amb, ambfp))
141 avinsert(avstore(&amb));
142 /* align */
143 fseek(ambfp, -((ftell(ambfp)-headlen)%AMBVALSIZ), 1);
144 } else if ((ambfp = fopen(afile, "w+")) != NULL)
145 initambfile(1);
146 else {
147 sprintf(errmsg, "cannot open ambient file \"%s\"", afile);
148 error(SYSTEM, errmsg);
149 }
150 nunflshed++; /* lie */
151 ambsync();
152 }
153
154
155 ambnotify(obj) /* record new modifier */
156 OBJECT obj;
157 {
158 static int hitlimit = 0;
159 register OBJREC *o = objptr(obj);
160 register char **amblp;
161
162 if (hitlimit || !ismodifier(o->otype))
163 return;
164 for (amblp = amblist; *amblp != NULL; amblp++)
165 if (!strcmp(o->oname, *amblp)) {
166 if (ambset[0] >= MAXASET) {
167 error(WARNING, "too many modifiers in ambient list");
168 hitlimit++;
169 return; /* should this be fatal? */
170 }
171 insertelem(ambset, obj);
172 return;
173 }
174 }
175
176
177 ambient(acol, r) /* compute ambient component for ray */
178 COLOR acol;
179 register RAY *r;
180 {
181 static int rdepth = 0; /* ambient recursion */
182 double d;
183
184 if (ambdiv <= 0) /* no ambient calculation */
185 goto dumbamb;
186 /* check number of bounces */
187 if (rdepth >= ambounce)
188 goto dumbamb;
189 /* check ambient list */
190 if (ambincl != -1 && r->ro != NULL &&
191 ambincl != inset(ambset, r->ro->omod))
192 goto dumbamb;
193
194 if (ambacc <= FTINY) { /* no ambient storage */
195 rdepth++;
196 d = doambient(acol, r, r->rweight, NULL, NULL);
197 rdepth--;
198 if (d == 0.0)
199 goto dumbamb;
200 return;
201 }
202 /* resort memory? */
203 checksort();
204 /* get ambient value */
205 setcolor(acol, 0.0, 0.0, 0.0);
206 d = sumambient(acol, r, rdepth,
207 &atrunk, thescene.cuorg, thescene.cusize);
208 if (d > FTINY)
209 scalecolor(acol, 1.0/d);
210 else {
211 d = makeambient(acol, r, rdepth++);
212 rdepth--;
213 }
214 if (d > FTINY)
215 return;
216 dumbamb: /* return global value */
217 copycolor(acol, ambval);
218 }
219
220
221 double
222 sumambient(acol, r, al, at, c0, s) /* get interpolated ambient value */
223 COLOR acol;
224 register RAY *r;
225 int al;
226 AMBTREE *at;
227 FVECT c0;
228 double s;
229 {
230 double d, e1, e2, wt, wsum;
231 COLOR ct;
232 FVECT ck0;
233 int i;
234 register int j;
235 register AMBVAL *av;
236 /* do this node */
237 wsum = 0.0;
238 for (av = at->alist; av != NULL; av = av->next) {
239 if (tracktime)
240 av->latick = ambclock++;
241 /*
242 * Ambient level test.
243 */
244 if (av->lvl > al) /* list sorted, so this works */
245 break;
246 if (av->weight < r->rweight-FTINY)
247 continue;
248 /*
249 * Ambient radius test.
250 */
251 e1 = 0.0;
252 for (j = 0; j < 3; j++) {
253 d = av->pos[j] - r->rop[j];
254 e1 += d * d;
255 }
256 e1 /= av->rad * av->rad;
257 if (e1 > ambacc*ambacc*1.21)
258 continue;
259 /*
260 * Normal direction test.
261 */
262 e2 = (1.0 - DOT(av->dir, r->ron)) * r->rweight;
263 if (e2 < 0.0) e2 = 0.0;
264 if (e1 + e2 > ambacc*ambacc*1.21)
265 continue;
266 /*
267 * Ray behind test.
268 */
269 d = 0.0;
270 for (j = 0; j < 3; j++)
271 d += (r->rop[j] - av->pos[j]) *
272 (av->dir[j] + r->ron[j]);
273 if (d*0.5 < -minarad*ambacc-.001)
274 continue;
275 /*
276 * Jittering final test reduces image artifacts.
277 */
278 wt = sqrt(e1) + sqrt(e2);
279 wt *= .9 + .2*urand(9015+samplendx);
280 if (wt > ambacc)
281 continue;
282 if (wt <= 1e-3)
283 wt = 1e3;
284 else
285 wt = 1.0 / wt;
286 wsum += wt;
287 extambient(ct, av, r->rop, r->ron);
288 scalecolor(ct, wt);
289 addcolor(acol, ct);
290 }
291 if (at->kid == NULL)
292 return(wsum);
293 /* do children */
294 s *= 0.5;
295 for (i = 0; i < 8; i++) {
296 for (j = 0; j < 3; j++) {
297 ck0[j] = c0[j];
298 if (1<<j & i)
299 ck0[j] += s;
300 if (r->rop[j] < ck0[j] - OCTSCALE*s)
301 break;
302 if (r->rop[j] > ck0[j] + (1.0+OCTSCALE)*s)
303 break;
304 }
305 if (j == 3)
306 wsum += sumambient(acol, r, al, at->kid+i, ck0, s);
307 }
308 return(wsum);
309 }
310
311
312 double
313 makeambient(acol, r, al) /* make a new ambient value */
314 COLOR acol;
315 register RAY *r;
316 int al;
317 {
318 AMBVAL amb;
319 FVECT gp, gd;
320 /* compute weight */
321 amb.weight = pow(AVGREFL, (double)al);
322 if (r->rweight < 0.2*amb.weight) /* heuristic */
323 amb.weight = r->rweight;
324 /* compute ambient */
325 amb.rad = doambient(acol, r, amb.weight, gp, gd);
326 if (amb.rad == 0.0)
327 return(0.0);
328 /* store it */
329 VCOPY(amb.pos, r->rop);
330 VCOPY(amb.dir, r->ron);
331 amb.lvl = al;
332 copycolor(amb.val, acol);
333 VCOPY(amb.gpos, gp);
334 VCOPY(amb.gdir, gd);
335 /* insert into tree */
336 avsave(&amb); /* and save to file */
337 return(amb.rad);
338 }
339
340
341 extambient(cr, ap, pv, nv) /* extrapolate value at pv, nv */
342 COLOR cr;
343 register AMBVAL *ap;
344 FVECT pv, nv;
345 {
346 FVECT v1, v2;
347 register int i;
348 double d;
349
350 d = 1.0; /* zeroeth order */
351 /* gradient due to translation */
352 for (i = 0; i < 3; i++)
353 d += ap->gpos[i]*(pv[i]-ap->pos[i]);
354 /* gradient due to rotation */
355 VCOPY(v1, ap->dir);
356 fcross(v2, v1, nv);
357 d += DOT(ap->gdir, v2);
358 if (d <= 0.0) {
359 setcolor(cr, 0.0, 0.0, 0.0);
360 return;
361 }
362 copycolor(cr, ap->val);
363 scalecolor(cr, d);
364 }
365
366
367 static
368 initambfile(creat) /* initialize ambient file */
369 int creat;
370 {
371 extern char *progname, *octname, VersionID[];
372
373 #ifdef F_SETLKW
374 aflock(creat ? F_WRLCK : F_RDLCK);
375 #endif
376 #ifdef MSDOS
377 setmode(fileno(ambfp), O_BINARY);
378 #endif
379 setbuf(ambfp, bmalloc(BUFSIZ+8));
380 if (creat) { /* new file */
381 newheader("RADIANCE", ambfp);
382 fprintf(ambfp, "%s -av %g %g %g -ab %d -aa %g ",
383 progname, colval(ambval,RED),
384 colval(ambval,GRN), colval(ambval,BLU),
385 ambounce, ambacc);
386 fprintf(ambfp, "-ad %d -as %d -ar %d %s\n",
387 ambdiv, ambssamp, ambres,
388 octname==NULL ? "" : octname);
389 fprintf(ambfp, "SOFTWARE= %s\n", VersionID);
390 fputformat(AMBFMT, ambfp);
391 putc('\n', ambfp);
392 putambmagic(ambfp);
393 } else if (checkheader(ambfp, AMBFMT, NULL) < 0 || !hasambmagic(ambfp))
394 error(USER, "bad ambient file");
395 }
396
397
398 static
399 avsave(av) /* insert and save an ambient value */
400 AMBVAL *av;
401 {
402 avinsert(avstore(av));
403 if (ambfp == NULL)
404 return;
405 if (writambval(av, ambfp) < 0)
406 goto writerr;
407 if (++nunflshed >= AMBFLUSH)
408 if (ambsync() == EOF)
409 goto writerr;
410 return;
411 writerr:
412 error(SYSTEM, "error writing ambient file");
413 }
414
415
416 static AMBVAL *
417 avstore(aval) /* allocate memory and store aval */
418 register AMBVAL *aval;
419 {
420 register AMBVAL *av;
421
422 if ((av = newambval()) == NULL)
423 error(SYSTEM, "out of memory in avstore");
424 copystruct(av, aval);
425 av->latick = ambclock;
426 av->next = NULL;
427 nambvals++;
428 return(av);
429 }
430
431
432 #define ATALLOCSZ 512 /* #/8 trees to allocate at once */
433
434 static AMBTREE *atfreelist = NULL; /* free ambient tree structures */
435
436
437 static
438 AMBTREE *
439 newambtree() /* allocate 8 ambient tree structs */
440 {
441 register AMBTREE *atp, *upperlim;
442
443 if (atfreelist == NULL) { /* get more nodes */
444 atfreelist = (AMBTREE *)bmalloc(ATALLOCSZ*8*sizeof(AMBTREE));
445 if (atfreelist == NULL)
446 return(NULL);
447 /* link new free list */
448 upperlim = atfreelist + 8*(ATALLOCSZ-1);
449 for (atp = atfreelist; atp < upperlim; atp += 8)
450 atp->kid = atp + 8;
451 atp->kid = NULL;
452 }
453 atp = atfreelist;
454 atfreelist = atp->kid;
455 bzero((char *)atp, 8*sizeof(AMBTREE));
456 return(atp);
457 }
458
459
460 static
461 freeambtree(atp) /* free 8 ambient tree structs */
462 AMBTREE *atp;
463 {
464 atp->kid = atfreelist;
465 atfreelist = atp;
466 }
467
468
469 static
470 avinsert(av) /* insert ambient value in our tree */
471 register AMBVAL *av;
472 {
473 register AMBTREE *at;
474 register AMBVAL *ap;
475 AMBVAL avh;
476 FVECT ck0;
477 double s;
478 int branch;
479 register int i;
480
481 if (av->rad <= FTINY)
482 error(CONSISTENCY, "zero ambient radius in avinsert");
483 at = &atrunk;
484 VCOPY(ck0, thescene.cuorg);
485 s = thescene.cusize;
486 while (s*(OCTSCALE/2) > av->rad*ambacc) {
487 if (at->kid == NULL)
488 if ((at->kid = newambtree()) == NULL)
489 error(SYSTEM, "out of memory in avinsert");
490 s *= 0.5;
491 branch = 0;
492 for (i = 0; i < 3; i++)
493 if (av->pos[i] > ck0[i] + s) {
494 ck0[i] += s;
495 branch |= 1 << i;
496 }
497 at = at->kid + branch;
498 }
499 avh.next = at->alist; /* order by increasing level */
500 for (ap = &avh; ap->next != NULL; ap = ap->next)
501 if (ap->next->lvl >= av->lvl)
502 break;
503 av->next = ap->next;
504 ap->next = av;
505 at->alist = avh.next;
506 }
507
508
509 static
510 unloadatree(at, f) /* unload an ambient value tree */
511 register AMBTREE *at;
512 int (*f)();
513 {
514 register AMBVAL *av;
515 register int i;
516 /* transfer values at this node */
517 for (av = at->alist; av != NULL; av = at->alist) {
518 at->alist = av->next;
519 (*f)(av);
520 }
521 if (at->kid == NULL)
522 return;
523 for (i = 0; i < 8; i++) /* transfer and free children */
524 unloadatree(at->kid+i, f);
525 freeambtree(at->kid);
526 at->kid = NULL;
527 }
528
529
530 static AMBVAL **avlist1, **avlist2; /* ambient value lists for sorting */
531 static int i_avlist; /* index for lists */
532
533
534 static
535 av2list(av)
536 AMBVAL *av;
537 {
538 #ifdef DEBUG
539 if (i_avlist >= nambvals)
540 error(CONSISTENCY, "too many ambient values in av2list1");
541 #endif
542 avlist1[i_avlist] = avlist2[i_avlist] = av;
543 i_avlist++;
544 }
545
546
547 static int
548 alatcmp(avp1, avp2) /* compare ambient values for MRA */
549 AMBVAL **avp1, **avp2;
550 {
551 return((**avp2).latick - (**avp1).latick);
552 }
553
554
555 static int
556 aposcmp(avp1, avp2) /* compare ambient value positions */
557 AMBVAL **avp1, **avp2;
558 {
559 return(*avp1 - *avp2);
560 }
561
562
563 #ifdef DEBUG
564 static int
565 avlmemi(avaddr) /* find list position from address */
566 AMBVAL *avaddr;
567 {
568 register AMBVAL **avlpp;
569
570 avlpp = (AMBVAL **)bsearch((char *)&avaddr, (char *)avlist2,
571 nambvals, sizeof(AMBVAL *), aposcmp);
572 if (avlpp == NULL)
573 error(CONSISTENCY, "address not found in avlmemi");
574 return(avlpp - avlist2);
575 }
576 #else
577 #define avlmemi(avaddr) ((AMBVAL **)bsearch((char *)&avaddr,(char *)avlist2, \
578 nambvals,sizeof(AMBVAL *),aposcmp) - avlist2)
579 #endif
580
581
582 static
583 sortambvals(always) /* resort ambient values */
584 int always;
585 {
586 AMBTREE oldatrunk;
587 AMBVAL tav, *tap, *pnext;
588 register int i, j;
589 /*
590 * The idea here is to minimize memory thrashing
591 * in VM systems by improving reference locality.
592 * We do this by periodically sorting our stored ambient
593 * values in memory in order of most recently to least
594 * recently accessed. This ordering was chosen so that new
595 * ambient values (which tend to be less important) go into
596 * higher memory with the infrequently accessed values.
597 * Since we expect our values to need sorting less
598 * frequently as the process continues, we double our
599 * waiting interval after each call.
600 * This routine is also called by setambacc() with
601 * the "always" parameter set to 1 so that the ambient
602 * tree will be rebuilt with the new accuracy parameter.
603 */
604 if (tracktime) { /* allocate pointer arrays to sort */
605 avlist1 = (AMBVAL **)malloc(nambvals*sizeof(AMBVAL *));
606 avlist2 = (AMBVAL **)malloc(nambvals*sizeof(AMBVAL *));
607 } else
608 avlist1 = avlist2 = NULL;
609 if (avlist2 == NULL) { /* no time tracking -- rebuild tree? */
610 if (avlist1 != NULL)
611 free((char *)avlist1);
612 if (always) { /* rebuild without sorting */
613 copystruct(&oldatrunk, &atrunk);
614 atrunk.alist = NULL;
615 atrunk.kid = NULL;
616 unloadatree(&oldatrunk, avinsert);
617 }
618 } else { /* sort memory by last access time */
619 /*
620 * Sorting memory is tricky because it isn't contiguous.
621 * We have to sort an array of pointers by MRA and also
622 * by memory position. We then copy values in "loops"
623 * to minimize memory hits. Nevertheless, we will visit
624 * everyone at least twice, and this is an expensive process
625 * when we're thrashing, which is when we need to do it.
626 */
627 #ifdef DEBUG
628 sprintf(errmsg, "sorting %u ambient values...", nambvals);
629 eputs(errmsg);
630 #endif
631 i_avlist = 0;
632 unloadatree(&atrunk, av2list); /* empty current tree */
633 #ifdef DEBUG
634 if (i_avlist < nambvals)
635 error(CONSISTENCY, "missing ambient values in sortambvals");
636 #endif
637 qsort((char *)avlist1, nambvals, sizeof(AMBVAL *), alatcmp);
638 qsort((char *)avlist2, nambvals, sizeof(AMBVAL *), aposcmp);
639 for (i = 0; i < nambvals; i++) {
640 if (avlist1[i] == NULL)
641 continue;
642 tap = avlist2[i];
643 copystruct(&tav, tap);
644 for (j = i; (pnext = avlist1[j]) != tap;
645 j = avlmemi(pnext)) {
646 copystruct(avlist2[j], pnext);
647 avinsert(avlist2[j]);
648 avlist1[j] = NULL;
649 }
650 copystruct(avlist2[j], &tav);
651 avinsert(avlist2[j]);
652 avlist1[j] = NULL;
653 }
654 free((char *)avlist1);
655 free((char *)avlist2);
656 if (sortintvl < SORT_INTVL<<6)
657 sortintvl <<= 1; /* wait twice as long next */
658 #ifdef DEBUG
659 eputs("done\n");
660 #endif
661 }
662 if (ambclock >= MAXACLOCK)
663 ambclock = MAXACLOCK/2;
664 lastsort = ambclock;
665 }
666
667
668 #ifdef F_SETLKW
669
670 static
671 aflock(typ) /* lock/unlock ambient file */
672 int typ;
673 {
674 static struct flock fls; /* static so initialized to zeroes */
675
676 fls.l_type = typ;
677 if (fcntl(fileno(ambfp), F_SETLKW, &fls) < 0)
678 error(SYSTEM, "cannot (un)lock ambient file");
679 }
680
681
682 int
683 ambsync() /* synchronize ambient file */
684 {
685 static FILE *ambinp = NULL;
686 static long lastpos = -1;
687 long flen;
688 AMBVAL avs;
689 register int n;
690
691 if (nunflshed == 0)
692 return(0);
693 if (lastpos < 0) /* initializing (locked in initambfile) */
694 goto syncend;
695 /* gain exclusive access */
696 aflock(F_WRLCK);
697 /* see if file has grown */
698 if ((flen = lseek(fileno(ambfp), 0L, 2)) < 0)
699 goto seekerr;
700 if (n = flen - lastpos) { /* file has grown */
701 if (ambinp == NULL) { /* use duplicate filedes */
702 ambinp = fdopen(dup(fileno(ambfp)), "r");
703 if (ambinp == NULL)
704 error(SYSTEM, "fdopen failed in ambsync");
705 }
706 if (fseek(ambinp, lastpos, 0) < 0)
707 goto seekerr;
708 while (n >= AMBVALSIZ) { /* load contributed values */
709 readambval(&avs, ambinp);
710 avinsert(avstore(&avs));
711 n -= AMBVALSIZ;
712 }
713 /*** seek always as safety measure
714 if (n) ***/ /* alignment */
715 if (lseek(fileno(ambfp), flen-n, 0) < 0)
716 goto seekerr;
717 }
718 #ifdef DEBUG
719 if (ambfp->_ptr - ambfp->_base != nunflshed*AMBVALSIZ) {
720 sprintf(errmsg, "ambient file buffer at %d rather than %d",
721 ambfp->_ptr - ambfp->_base,
722 nunflshed*AMBVALSIZ);
723 error(CONSISTENCY, errmsg);
724 }
725 #endif
726 syncend:
727 n = fflush(ambfp); /* calls write() at last */
728 if ((lastpos = lseek(fileno(ambfp), 0L, 1)) < 0)
729 goto seekerr;
730 aflock(F_UNLCK); /* release file */
731 nunflshed = 0;
732 return(n);
733 seekerr:
734 error(SYSTEM, "seek failed in ambsync");
735 }
736
737 #else
738
739 int
740 ambsync() /* flush ambient file */
741 {
742 if (nunflshed == 0)
743 return(0);
744 nunflshed = 0;
745 return(fflush(ambfp));
746 }
747
748 #endif