--- ray/src/rt/ambient.c 1992/07/16 15:53:42 2.9 +++ ray/src/rt/ambient.c 2003/06/30 14:59:12 2.52 @@ -1,109 +1,225 @@ -/* Copyright (c) 1991 Regents of the University of California */ - #ifndef lint -static char SCCSid[] = "$SunId$ LBL"; +static const char RCSid[] = "$Id: ambient.c,v 2.52 2003/06/30 14:59:12 schorsch Exp $"; #endif - /* * ambient.c - routines dealing with ambient (inter-reflected) component. * - * The macro AMBFLUSH (if defined) is the number of ambient values - * to wait before flushing to the ambient file. - * - * 5/9/86 + * Declarations of external symbols in ambient.h */ -#include "ray.h" +#include "copyright.h" -#include "octree.h" +#include +#include "platform.h" +#include "ray.h" #include "otypes.h" - #include "ambient.h" - #include "random.h" -#define OCTSCALE 0.5 /* ceil((valid rad.)/(cube size)) */ +#ifndef OCTSCALE +#define OCTSCALE 1.0 /* ceil((valid rad.)/(cube size)) */ +#endif -typedef struct ambtree { - AMBVAL *alist; /* ambient value list */ - struct ambtree *kid; /* 8 child nodes */ -} AMBTREE; /* ambient octree */ +extern char *shm_boundary; /* memory sharing boundary */ -extern CUBE thescene; /* contains space boundaries */ +#define MAXASET 511 /* maximum number of elements in ambient set */ +OBJECT ambset[MAXASET+1]={0}; /* ambient include/exclude set */ -#define MAXASET 511 /* maximum number of elements in ambient set */ -OBJECT ambset[MAXASET+1]={0}; /* ambient include/exclude set */ +double maxarad; /* maximum ambient radius */ +double minarad; /* minimum ambient radius */ -double maxarad; /* maximum ambient radius */ -double minarad; /* minimum ambient radius */ +static AMBTREE atrunk; /* our ambient trunk node */ -static AMBTREE atrunk; /* our ambient trunk node */ - static FILE *ambfp = NULL; /* ambient file pointer */ -static char *afname; /* ambient file name */ +static int nunflshed = 0; /* number of unflushed ambient values */ -#define AMBFLUSH (BUFSIZ/AMBVALSIZ) +#ifndef SORT_THRESH +#ifdef SMLMEM +#define SORT_THRESH ((3L<<20)/sizeof(AMBVAL)) +#else +#define SORT_THRESH ((9L<<20)/sizeof(AMBVAL)) +#endif +#endif +#ifndef SORT_INTVL +#define SORT_INTVL (SORT_THRESH<<1) +#endif +#ifndef MAX_SORT_INTVL +#define MAX_SORT_INTVL (SORT_INTVL<<6) +#endif -#define newambval() (AMBVAL *)bmalloc(sizeof(AMBVAL)) +static double avsum = 0.; /* computed ambient value sum (log) */ +static unsigned int navsum = 0; /* number of values in avsum */ +static unsigned int nambvals = 0; /* total number of indirect values */ +static unsigned int nambshare = 0; /* number of values from file */ +static unsigned long ambclock = 0; /* ambient access clock */ +static unsigned long lastsort = 0; /* time of last value sort */ +static long sortintvl = SORT_INTVL; /* time until next sort */ +static FILE *ambinp = NULL; /* auxiliary file for input */ +static long lastpos = -1; /* last flush position */ -#define newambtree() (AMBTREE *)calloc(8, sizeof(AMBTREE)) +#define MAXACLOCK (1L<<30) /* clock turnover value */ + /* + * Track access times unless we are sharing ambient values + * through memory on a multiprocessor, when we want to avoid + * claiming our own memory (copy on write). Go ahead anyway + * if more than two thirds of our values are unshared. + * Compile with -Dtracktime=0 to turn this code off. + */ +#ifndef tracktime +#define tracktime (shm_boundary == NULL || nambvals > 3*nambshare) +#endif -extern long ftell(), lseek(); +#define AMBFLUSH (BUFSIZ/AMBVALSIZ) +#define newambval() (AMBVAL *)malloc(sizeof(AMBVAL)) +#define freeav(av) free((void *)av); +static void initambfile(), avsave(), avinsert(), sortambvals(), unloadatree(); +static int avlmemi(); +static AMBVAL *avstore(); +#ifdef F_SETLKW +static void aflock(); +#endif + + +void setambres(ar) /* set ambient resolution */ int ar; { + ambres = ar < 0 ? 0 : ar; /* may be done already */ /* set min & max radii */ if (ar <= 0) { - minarad = 0.0; + minarad = 0; maxarad = thescene.cusize / 2.0; } else { minarad = thescene.cusize / ar; - maxarad = 16.0 * minarad; /* heuristic */ + maxarad = 64 * minarad; /* heuristic */ if (maxarad > thescene.cusize / 2.0) maxarad = thescene.cusize / 2.0; } - if (maxarad <= FTINY) - maxarad = .001; + if (minarad <= FTINY) + minarad = 10*FTINY; + if (maxarad <= minarad) + maxarad = 64 * minarad; } -setambient(afile) /* initialize calculation */ -char *afile; +void +setambacc(newa) /* set ambient accuracy */ +double newa; { - long headlen; - AMBVAL amb; + double ambdiff; + + if (newa < 0.0) + newa = 0.0; + ambdiff = fabs(newa - ambacc); + if (ambdiff >= .01 && (ambacc = newa) > FTINY && nambvals > 0) + sortambvals(1); /* rebuild tree */ +} + + +void +setambient() /* initialize calculation */ +{ + int readonly = 0; + long pos, flen; + AMBVAL amb; + /* make sure we're fresh */ + ambdone(); /* init ambient limits */ setambres(ambres); + setambacc(ambacc); + if (ambfile == NULL || !ambfile[0]) + return; + if (ambacc <= FTINY) { + sprintf(errmsg, "zero ambient accuracy so \"%s\" not opened", + ambfile); + error(WARNING, errmsg); + return; + } /* open ambient file */ - if ((afname = afile) != NULL) - if ((ambfp = fopen(afile, "r+")) != NULL) { - initambfile(0); - headlen = ftell(ambfp); - while (readambval(&amb, ambfp)) - avinsert(&amb, &atrunk, thescene.cuorg, - thescene.cusize); - /* align */ - fseek(ambfp, -((ftell(ambfp)-headlen)%AMBVALSIZ), 1); - } else if ((ambfp = fopen(afile, "w")) != NULL) - initambfile(1); - else { - sprintf(errmsg, "cannot open ambient file \"%s\"", - afile); - error(SYSTEM, errmsg); + if ((ambfp = fopen(ambfile, "r+")) == NULL) + readonly = (ambfp = fopen(ambfile, "r")) != NULL; + if (ambfp != NULL) { + initambfile(0); /* file exists */ + pos = ftell(ambfp); + while (readambval(&amb, ambfp)) + avinsert(avstore(&amb)); + nambshare = nambvals; /* share loaded values */ + if (readonly) { + sprintf(errmsg, + "loaded %u values from read-only ambient file", + nambvals); + error(WARNING, errmsg); + fclose(ambfp); /* close file so no writes */ + ambfp = NULL; + return; /* avoid ambsync() */ } + /* align file pointer */ + pos += (long)nambvals*AMBVALSIZ; + flen = lseek(fileno(ambfp), (off_t)0L, 2); + if (flen != pos) { + sprintf(errmsg, + "ignoring last %ld values in ambient file (corrupted)", + (flen - pos)/AMBVALSIZ); + error(WARNING, errmsg); + fseek(ambfp, pos, 0); +#ifndef _WIN32 /* XXX we need a replacement for that one */ + ftruncate(fileno(ambfp), (off_t)pos); +#endif + } + } else if ((ambfp = fopen(ambfile, "w+")) != NULL) { + initambfile(1); /* else create new file */ + } else { + sprintf(errmsg, "cannot open ambient file \"%s\"", ambfile); + error(SYSTEM, errmsg); + } + nunflshed++; /* lie */ + ambsync(); } +void +ambdone() /* close ambient file and free memory */ +{ + if (ambfp != NULL) { /* close ambient file */ + ambsync(); + fclose(ambfp); + ambfp = NULL; + if (ambinp != NULL) { + fclose(ambinp); + ambinp = NULL; + } + lastpos = -1; + } + /* free ambient tree */ + unloadatree(&atrunk, free); + /* reset state variables */ + avsum = 0.; + navsum = 0; + nambvals = 0; + nambshare = 0; + ambclock = 0; + lastsort = 0; + sortintvl = SORT_INTVL; +} + + +void ambnotify(obj) /* record new modifier */ -OBJECT obj; +OBJECT obj; { static int hitlimit = 0; - register OBJREC *o = objptr(obj); + register OBJREC *o; register char **amblp; + if (obj == OVOID) { /* starting over */ + ambset[0] = 0; + hitlimit = 0; + return; + } + o = objptr(obj); if (hitlimit || !ismodifier(o->otype)) return; for (amblp = amblist; *amblp != NULL; amblp++) @@ -119,12 +235,14 @@ OBJECT obj; } -ambient(acol, r) /* compute ambient component for ray */ +void +ambient(acol, r, nrm) /* compute ambient component for ray */ COLOR acol; register RAY *r; +FVECT nrm; { static int rdepth = 0; /* ambient recursion */ - double d; + double d, l; if (ambdiv <= 0) /* no ambient calculation */ goto dumbamb; @@ -140,66 +258,99 @@ register RAY *r; rdepth++; d = doambient(acol, r, r->rweight, NULL, NULL); rdepth--; - if (d == 0.0) + if (d <= FTINY) goto dumbamb; return; } + + if (tracktime) /* sort to minimize thrashing */ + sortambvals(0); /* get ambient value */ setcolor(acol, 0.0, 0.0, 0.0); - d = sumambient(acol, r, rdepth, + d = sumambient(acol, r, nrm, rdepth, &atrunk, thescene.cuorg, thescene.cusize); - if (d > FTINY) + if (d > FTINY) { scalecolor(acol, 1.0/d); - else { - d = makeambient(acol, r, rdepth++); - rdepth--; + return; } + rdepth++; /* need to cache new value */ + d = makeambient(acol, r, nrm, rdepth-1); + rdepth--; if (d > FTINY) return; dumbamb: /* return global value */ copycolor(acol, ambval); + if (ambvwt <= 0 | navsum == 0) + return; + l = bright(ambval); /* average in computations */ + if (l > FTINY) { + d = (log(l)*(double)ambvwt + avsum) / + (double)(ambvwt + navsum); + d = exp(d) / l; + scalecolor(acol, d); /* apply color of ambval */ + } else { + d = exp( avsum / (double)navsum ); + setcolor(acol, d, d, d); /* neutral color */ + } } double -sumambient(acol, r, al, at, c0, s) /* get interpolated ambient value */ +sumambient(acol, r, rn, al, at, c0, s) /* get interpolated ambient value */ COLOR acol; register RAY *r; +FVECT rn; int al; -AMBTREE *at; +AMBTREE *at; FVECT c0; -double s; +double s; { - extern double sqrt(); - double d, e1, e2, wt, wsum; + double d, e1, e2, wt, wsum; COLOR ct; FVECT ck0; int i; register int j; - register AMBVAL *av; - /* do this node */ + register AMBVAL *av; + wsum = 0.0; + /* do this node */ for (av = at->alist; av != NULL; av = av->next) { + double rn_dot = -2.0; + if (tracktime) + av->latick = ambclock; /* * Ambient level test. */ - if (av->lvl > al || av->weight < r->rweight-FTINY) + if (av->lvl > al) /* list sorted, so this works */ + break; + if (av->weight < r->rweight-FTINY) continue; /* * Ambient radius test. */ - e1 = 0.0; - for (j = 0; j < 3; j++) { - d = av->pos[j] - r->rop[j]; - e1 += d * d; - } + d = av->pos[0] - r->rop[0]; + e1 = d * d; + d = av->pos[1] - r->rop[1]; + e1 += d * d; + d = av->pos[2] - r->rop[2]; + e1 += d * d; e1 /= av->rad * av->rad; if (e1 > ambacc*ambacc*1.21) continue; /* - * Normal direction test. + * Direction test using closest normal. */ - e2 = (1.0 - DOT(av->dir, r->ron)) * r->rweight; + d = DOT(av->dir, r->ron); + if (rn != r->ron) { + rn_dot = DOT(av->dir, rn); + if (rn_dot > 1.0-FTINY) + rn_dot = 1.0-FTINY; + if (rn_dot >= d-FTINY) { + d = rn_dot; + rn_dot = -2.0; + } + } + e2 = (1.0 - d) * r->rweight; if (e2 < 0.0) e2 = 0.0; if (e1 + e2 > ambacc*ambacc*1.21) continue; @@ -215,16 +366,24 @@ double s; /* * Jittering final test reduces image artifacts. */ - wt = sqrt(e1) + sqrt(e2); - wt *= .9 + .2*urand(9015+samplendx); - if (wt > ambacc) + e1 = sqrt(e1); + e2 = sqrt(e2); + wt = e1 + e2; + if (wt > ambacc*(.9+.2*urand(9015+samplendx))) continue; + /* + * Recompute directional error using perturbed normal + */ + if (rn_dot > 0.0) { + e2 = sqrt((1.0 - rn_dot)*r->rweight); + wt = e1 + e2; + } if (wt <= 1e-3) wt = 1e3; else wt = 1.0 / wt; wsum += wt; - extambient(ct, av, r->rop, r->ron); + extambient(ct, av, r->rop, rn); scalecolor(ct, wt); addcolor(acol, ct); } @@ -243,27 +402,28 @@ double s; break; } if (j == 3) - wsum += sumambient(acol, r, al, at->kid+i, ck0, s); + wsum += sumambient(acol, r, rn, al, at->kid+i, ck0, s); } return(wsum); } double -makeambient(acol, r, al) /* make a new ambient value */ +makeambient(acol, r, rn, al) /* make a new ambient value */ COLOR acol; register RAY *r; +FVECT rn; int al; { - AMBVAL amb; + AMBVAL amb; FVECT gp, gd; /* compute weight */ amb.weight = pow(AVGREFL, (double)al); - if (r->rweight < 0.2*amb.weight) /* heuristic */ + if (r->rweight < 0.1*amb.weight) /* heuristic */ amb.weight = r->rweight; /* compute ambient */ amb.rad = doambient(acol, r, amb.weight, gp, gd); - if (amb.rad == 0.0) + if (amb.rad <= FTINY) return(0.0); /* store it */ VCOPY(amb.pos, r->rop); @@ -274,27 +434,29 @@ int al; VCOPY(amb.gdir, gd); /* insert into tree */ avsave(&amb); /* and save to file */ + if (rn != r->ron) + extambient(acol, &amb, r->rop, rn); /* texture */ return(amb.rad); } +void extambient(cr, ap, pv, nv) /* extrapolate value at pv, nv */ COLOR cr; -register AMBVAL *ap; +register AMBVAL *ap; FVECT pv, nv; { - FVECT v1, v2; + FVECT v1; register int i; - double d; + double d; d = 1.0; /* zeroeth order */ /* gradient due to translation */ for (i = 0; i < 3; i++) d += ap->gpos[i]*(pv[i]-ap->pos[i]); /* gradient due to rotation */ - VCOPY(v1, ap->dir); - fcross(v2, v1, nv); - d += DOT(ap->gdir, v2); + VCROSS(v1, ap->dir, nv); + d += DOT(ap->gdir, v1); if (d <= 0.0) { setcolor(cr, 0.0, 0.0, 0.0); return; @@ -304,76 +466,139 @@ FVECT pv, nv; } -static +static void initambfile(creat) /* initialize ambient file */ int creat; { - extern char *progname, *octname, VersionID[]; + extern char *progname, *octname; + static char *mybuf = NULL; - setbuf(ambfp, bmalloc(BUFSIZ)); +#ifdef F_SETLKW + aflock(creat ? F_WRLCK : F_RDLCK); +#endif + SET_FILE_BINARY(ambfp); + if (mybuf == NULL) + mybuf = (char *)bmalloc(BUFSIZ+8); + setbuf(ambfp, mybuf); if (creat) { /* new file */ - fprintf(ambfp, "%s -av %g %g %g -ab %d -aa %g ", + newheader("RADIANCE", ambfp); + fprintf(ambfp, "%s -av %g %g %g -aw %d -ab %d -aa %g ", progname, colval(ambval,RED), colval(ambval,GRN), colval(ambval,BLU), - ambounce, ambacc); - fprintf(ambfp, "-ad %d -as %d -ar %d %s\n", - ambdiv, ambssamp, ambres, - octname==NULL ? "" : octname); + ambvwt, ambounce, ambacc); + fprintf(ambfp, "-ad %d -as %d -ar %d ", + ambdiv, ambssamp, ambres); + if (octname != NULL) + printargs(1, &octname, ambfp); + else + fputc('\n', ambfp); fprintf(ambfp, "SOFTWARE= %s\n", VersionID); + fputnow(ambfp); fputformat(AMBFMT, ambfp); putc('\n', ambfp); putambmagic(ambfp); - fflush(ambfp); - } else if (checkheader(ambfp, AMBFMT, NULL) < 0 - || !hasambmagic(ambfp)) { - sprintf(errmsg, "\"%s\" is not an ambient file", afname); - error(USER, errmsg); - } + } else if (checkheader(ambfp, AMBFMT, NULL) < 0 || !hasambmagic(ambfp)) + error(USER, "bad ambient file"); } -static +static void avsave(av) /* insert and save an ambient value */ -AMBVAL *av; +AMBVAL *av; { - static int nunflshed = 0; - - avinsert(av, &atrunk, thescene.cuorg, thescene.cusize); + avinsert(avstore(av)); if (ambfp == NULL) return; if (writambval(av, ambfp) < 0) goto writerr; - if (++nunflshed >= AMBFLUSH) { + if (++nunflshed >= AMBFLUSH) if (ambsync() == EOF) goto writerr; - nunflshed = 0; - } return; writerr: - error(SYSTEM, "error writing ambient file"); + error(SYSTEM, "error writing to ambient file"); } -static -avinsert(aval, at, c0, s) /* insert ambient value in a tree */ -AMBVAL *aval; -register AMBTREE *at; -FVECT c0; -double s; +static AMBVAL * +avstore(aval) /* allocate memory and store aval */ +register AMBVAL *aval; { - FVECT ck0; - int branch; register AMBVAL *av; - register int i; + double d; if ((av = newambval()) == NULL) - goto memerr; + error(SYSTEM, "out of memory in avstore"); copystruct(av, aval); - VCOPY(ck0, c0); + av->latick = ambclock; + av->next = NULL; + nambvals++; + d = bright(av->val); + if (d > FTINY) { /* add to log sum for averaging */ + avsum += log(d); + navsum++; + } + return(av); +} + + +#define ATALLOCSZ 512 /* #/8 trees to allocate at once */ + +static AMBTREE *atfreelist = NULL; /* free ambient tree structures */ + + +static AMBTREE * +newambtree() /* allocate 8 ambient tree structs */ +{ + register AMBTREE *atp, *upperlim; + + if (atfreelist == NULL) { /* get more nodes */ + atfreelist = (AMBTREE *)malloc(ATALLOCSZ*8*sizeof(AMBTREE)); + if (atfreelist == NULL) + return(NULL); + /* link new free list */ + upperlim = atfreelist + 8*(ATALLOCSZ-1); + for (atp = atfreelist; atp < upperlim; atp += 8) + atp->kid = atp + 8; + atp->kid = NULL; + } + atp = atfreelist; + atfreelist = atp->kid; + memset((char *)atp, '\0', 8*sizeof(AMBTREE)); + return(atp); +} + + +static void +freeambtree(atp) /* free 8 ambient tree structs */ +AMBTREE *atp; +{ + atp->kid = atfreelist; + atfreelist = atp; +} + + +static void +avinsert(av) /* insert ambient value in our tree */ +register AMBVAL *av; +{ + register AMBTREE *at; + register AMBVAL *ap; + AMBVAL avh; + FVECT ck0; + double s; + int branch; + register int i; + + if (av->rad <= FTINY) + error(CONSISTENCY, "zero ambient radius in avinsert"); + at = &atrunk; + VCOPY(ck0, thescene.cuorg); + s = thescene.cusize; while (s*(OCTSCALE/2) > av->rad*ambacc) { if (at->kid == NULL) if ((at->kid = newambtree()) == NULL) - goto memerr; + error(SYSTEM, "out of memory in avinsert"); s *= 0.5; branch = 0; for (i = 0; i < 3; i++) @@ -383,48 +608,281 @@ double s; } at = at->kid + branch; } - av->next = at->alist; - at->alist = av; - return; -memerr: - error(SYSTEM, "out of memory in avinsert"); + avh.next = at->alist; /* order by increasing level */ + for (ap = &avh; ap->next != NULL; ap = ap->next) + if (ap->next->lvl >= av->lvl) + break; + av->next = ap->next; + ap->next = av; + at->alist = avh.next; } -#include +static void +unloadatree(at, f) /* unload an ambient value tree */ +register AMBTREE *at; +void (*f)(); +{ + register AMBVAL *av; + register int i; + /* transfer values at this node */ + for (av = at->alist; av != NULL; av = at->alist) { + at->alist = av->next; + (*f)(av); + } + if (at->kid == NULL) + return; + for (i = 0; i < 8; i++) /* transfer and free children */ + unloadatree(at->kid+i, f); + freeambtree(at->kid); + at->kid = NULL; +} -static +static struct avl { + AMBVAL *p; + unsigned long t; +} *avlist1; /* ambient value list with ticks */ +static AMBVAL **avlist2; /* memory positions for sorting */ +static int i_avlist; /* index for lists */ + + +static int +av2list(av) +register AMBVAL *av; +{ +#ifdef DEBUG + if (i_avlist >= nambvals) + error(CONSISTENCY, "too many ambient values in av2list1"); +#endif + avlist1[i_avlist].p = avlist2[i_avlist] = av; + avlist1[i_avlist++].t = av->latick; +} + + +static int +alatcmp(av1, av2) /* compare ambient values for MRA */ +struct avl *av1, *av2; +{ + register long lc = av2->t - av1->t; + return(lc<0 ? -1 : lc>0 ? 1 : 0); +} + + +/* GW NOTE 2002/10/3: + * I used to compare AMBVAL pointers, but found that this was the + * cause of a serious consistency error with gcc, since the optimizer + * uses some dangerous trick in pointer subtraction that + * assumes pointers differ by exact struct size increments. + */ +static int +aposcmp(avp1, avp2) /* compare ambient value positions */ +const void *avp1, *avp2; +{ + register long diff = *(char * const *)avp1 - *(char * const *)avp2; + if (diff < 0) + return(-1); + return(diff > 0); +} + +#if 1 +static int +avlmemi(avaddr) /* find list position from address */ +AMBVAL *avaddr; +{ + register AMBVAL **avlpp; + + avlpp = (AMBVAL **)bsearch((char *)&avaddr, (char *)avlist2, + nambvals, sizeof(AMBVAL *), aposcmp); + if (avlpp == NULL) + error(CONSISTENCY, "address not found in avlmemi"); + return(avlpp - avlist2); +} +#else +#define avlmemi(avaddr) ((AMBVAL **)bsearch((char *)&avaddr,(char *)avlist2, \ + nambvals,sizeof(AMBVAL *),aposcmp) - avlist2) +#endif + + +static void +sortambvals(always) /* resort ambient values */ +int always; +{ + AMBTREE oldatrunk; + AMBVAL tav, *tap, *pnext; + register int i, j; + /* see if it's time yet */ + if (!always && (ambclock++ < lastsort+sortintvl || + nambvals < SORT_THRESH)) + return; + /* + * The idea here is to minimize memory thrashing + * in VM systems by improving reference locality. + * We do this by periodically sorting our stored ambient + * values in memory in order of most recently to least + * recently accessed. This ordering was chosen so that new + * ambient values (which tend to be less important) go into + * higher memory with the infrequently accessed values. + * Since we expect our values to need sorting less + * frequently as the process continues, we double our + * waiting interval after each call. + * This routine is also called by setambacc() with + * the "always" parameter set to 1 so that the ambient + * tree will be rebuilt with the new accuracy parameter. + */ + if (tracktime) { /* allocate pointer arrays to sort */ + avlist2 = (AMBVAL **)malloc(nambvals*sizeof(AMBVAL *)); + avlist1 = (struct avl *)malloc(nambvals*sizeof(struct avl)); + } else { + avlist2 = NULL; + avlist1 = NULL; + } + if (avlist1 == NULL) { /* no time tracking -- rebuild tree? */ + if (avlist2 != NULL) + free((void *)avlist2); + if (always) { /* rebuild without sorting */ + copystruct(&oldatrunk, &atrunk); + atrunk.alist = NULL; + atrunk.kid = NULL; + unloadatree(&oldatrunk, avinsert); + } + } else { /* sort memory by last access time */ + /* + * Sorting memory is tricky because it isn't contiguous. + * We have to sort an array of pointers by MRA and also + * by memory position. We then copy values in "loops" + * to minimize memory hits. Nevertheless, we will visit + * everyone at least twice, and this is an expensive process + * when we're thrashing, which is when we need to do it. + */ +#ifdef DEBUG + sprintf(errmsg, "sorting %u ambient values at ambclock=%lu...", + nambvals, ambclock); + eputs(errmsg); +#endif + i_avlist = 0; + unloadatree(&atrunk, av2list); /* empty current tree */ +#ifdef DEBUG + if (i_avlist < nambvals) + error(CONSISTENCY, "missing ambient values in sortambvals"); +#endif + qsort((char *)avlist1, nambvals, sizeof(struct avl), alatcmp); + qsort((char *)avlist2, nambvals, sizeof(AMBVAL *), aposcmp); + for (i = 0; i < nambvals; i++) { + if (avlist1[i].p == NULL) + continue; + tap = avlist2[i]; + copystruct(&tav, tap); + for (j = i; (pnext = avlist1[j].p) != tap; + j = avlmemi(pnext)) { + copystruct(avlist2[j], pnext); + avinsert(avlist2[j]); + avlist1[j].p = NULL; + } + copystruct(avlist2[j], &tav); + avinsert(avlist2[j]); + avlist1[j].p = NULL; + } + free((void *)avlist1); + free((void *)avlist2); + /* compute new sort interval */ + sortintvl = ambclock - lastsort; + if (sortintvl >= MAX_SORT_INTVL/2) + sortintvl = MAX_SORT_INTVL; + else + sortintvl <<= 1; /* wait twice as long next */ +#ifdef DEBUG + eputs("done\n"); +#endif + } + if (ambclock >= MAXACLOCK) + ambclock = MAXACLOCK/2; + lastsort = ambclock; +} + + +#ifdef F_SETLKW + +static void +aflock(typ) /* lock/unlock ambient file */ +int typ; +{ + static struct flock fls; /* static so initialized to zeroes */ + + fls.l_type = typ; + if (fcntl(fileno(ambfp), F_SETLKW, &fls) < 0) + error(SYSTEM, "cannot (un)lock ambient file"); +} + + +int ambsync() /* synchronize ambient file */ { - static FILE *ambinp = NULL; - struct flock fls; - AMBVAL avs; - long lastpos, flen; + long flen; + AMBVAL avs; register int n; + + if (nunflshed == 0) + return(0); + if (lastpos < 0) /* initializing (locked in initambfile) */ + goto syncend; /* gain exclusive access */ - fls.l_type = F_WRLCK; - fls.l_whence = 0; - fls.l_start = 0L; - fls.l_len = 0L; - if (fcntl(fileno(ambfp), F_SETLKW, &fls) < 0) - error(SYSTEM, "cannot lock ambient file"); + aflock(F_WRLCK); /* see if file has grown */ - lastpos = lseek(fileno(ambfp), 0L, 1); /* get previous position */ - flen = lseek(fileno(ambfp), 0L, 2); /* new(?) file length */ - if (n = (flen - lastpos)%AMBVALSIZ) /* assure alignment */ - lseek(fileno(ambfp), (long)-n, 1); - if (n = (flen - lastpos)/AMBVALSIZ) { /* file has grown */ - if (ambinp == NULL && (ambinp = fopen(afname, "r")) == NULL) - error(SYSTEM, "cannot reopen ambient file"); - fseek(ambinp, lastpos, 0); /* go to previous position */ - while (n--) { /* load contributed values */ - readambval(&avs, ambinp); - avinsert(&avs,&atrunk,thescene.cuorg,thescene.cusize); + if ((flen = lseek(fileno(ambfp), (off_t)0L, 2)) < 0) + goto seekerr; + if (n = flen - lastpos) { /* file has grown */ + if (ambinp == NULL) { /* use duplicate filedes */ + ambinp = fdopen(dup(fileno(ambfp)), "r"); + if (ambinp == NULL) + error(SYSTEM, "fdopen failed in ambsync"); } + if (fseek(ambinp, lastpos, 0) < 0) + goto seekerr; + while (n >= AMBVALSIZ) { /* load contributed values */ + if (!readambval(&avs, ambinp)) { + sprintf(errmsg, + "ambient file \"%s\" corrupted near character %ld", + ambfile, flen - n); + error(WARNING, errmsg); + break; + } + avinsert(avstore(&avs)); + n -= AMBVALSIZ; + } + /*** seek always as safety measure + if (n) ***/ /* alignment */ + if (lseek(fileno(ambfp), (off_t)(flen-n), 0) < 0) + goto seekerr; } +#ifdef DEBUG + if (ambfp->_ptr - ambfp->_base != nunflshed*AMBVALSIZ) { + sprintf(errmsg, "ambient file buffer at %d rather than %d", + ambfp->_ptr - ambfp->_base, + nunflshed*AMBVALSIZ); + error(CONSISTENCY, errmsg); + } +#endif +syncend: n = fflush(ambfp); /* calls write() at last */ - fls.l_type = F_UNLCK; /* release file */ - fcntl(fileno(ambfp), F_SETLKW, &fls); + if ((lastpos = lseek(fileno(ambfp), (off_t)0L, 1)) < 0) + goto seekerr; + aflock(F_UNLCK); /* release file */ + nunflshed = 0; return(n); +seekerr: + error(SYSTEM, "seek failed in ambsync"); } + +#else + +int +ambsync() /* flush ambient file */ +{ + if (nunflshed == 0) + return(0); + nunflshed = 0; + return(fflush(ambfp)); +} + +#endif