1 |
/* Copyright (c) 1993 Regents of the University of California */ |
2 |
|
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#ifndef lint |
4 |
static char SCCSid[] = "$SunId$ LBL"; |
5 |
#endif |
6 |
|
7 |
/* |
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* 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 |
#define MAXASET 511 /* maximum number of elements in ambient set */ |
31 |
OBJECT ambset[MAXASET+1]={0}; /* ambient include/exclude set */ |
32 |
|
33 |
double maxarad; /* maximum ambient radius */ |
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double minarad; /* minimum ambient radius */ |
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|
36 |
static AMBTREE atrunk; /* our ambient trunk node */ |
37 |
|
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static FILE *ambfp = NULL; /* ambient file pointer */ |
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static int nunflshed = 0; /* number of unflushed ambient values */ |
40 |
|
41 |
#define AMBFLUSH (BUFSIZ/AMBVALSIZ) |
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|
43 |
#define newambval() (AMBVAL *)bmalloc(sizeof(AMBVAL)) |
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|
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#define newambtree() (AMBTREE *)calloc(8, sizeof(AMBTREE)) |
46 |
#define freeambtree(t) free((char *)(t)) |
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|
48 |
extern long ftell(), lseek(); |
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static int initambfile(), avsave(), avinsert(), loadatree(); |
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static AMBVAL *avstore(); |
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#ifdef F_SETLKW |
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static aflock(); |
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#endif |
54 |
|
55 |
|
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setambres(ar) /* set ambient resolution */ |
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int ar; |
58 |
{ |
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ambres = ar < 0 ? 0 : ar; /* may be done already */ |
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/* set min & max radii */ |
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if (ar <= 0) { |
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minarad = 0.0; |
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maxarad = thescene.cusize / 2.0; |
64 |
} else { |
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minarad = thescene.cusize / ar; |
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maxarad = 16.0 * minarad; /* heuristic */ |
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if (maxarad > thescene.cusize / 2.0) |
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maxarad = thescene.cusize / 2.0; |
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} |
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if (maxarad <= FTINY) |
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maxarad = .001; |
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} |
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|
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|
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setambacc(newa) /* set ambient accuracy */ |
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double newa; |
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{ |
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static double oldambacc = -1.0; |
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AMBTREE oldatrunk; |
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|
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ambacc = newa < 0.0 ? 0.0 : newa; /* may be done already */ |
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if (oldambacc < -FTINY) |
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oldambacc = ambacc; /* do nothing first call */ |
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if (fabs(newa - oldambacc) < 0.01) |
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return; /* insignificant -- don't bother */ |
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if (ambacc <= FTINY) |
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return; /* cannot build new tree */ |
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/* else need to rebuild tree */ |
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copystruct(&oldatrunk, &atrunk); |
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atrunk.alist = NULL; |
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atrunk.kid = NULL; |
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loadatree(&oldatrunk); |
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oldambacc = ambacc; /* remeber setting for next call */ |
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} |
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|
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|
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setambient(afile) /* initialize calculation */ |
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char *afile; |
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{ |
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long headlen; |
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AMBVAL amb; |
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/* init ambient limits */ |
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setambres(ambres); |
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setambacc(ambacc); |
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if (afile == NULL) |
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return; |
107 |
if (ambacc <= FTINY) { |
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sprintf(errmsg, "zero ambient accuracy so \"%s\" not opened", |
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afile); |
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error(WARNING, errmsg); |
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return; |
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} |
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/* open ambient file */ |
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if ((ambfp = fopen(afile, "r+")) != NULL) { |
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initambfile(0); |
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headlen = ftell(ambfp); |
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while (readambval(&amb, ambfp)) |
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avinsert(avstore(&amb)); |
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/* align */ |
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fseek(ambfp, -((ftell(ambfp)-headlen)%AMBVALSIZ), 1); |
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} else if ((ambfp = fopen(afile, "w+")) != NULL) |
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initambfile(1); |
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else { |
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sprintf(errmsg, "cannot open ambient file \"%s\"", afile); |
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error(SYSTEM, errmsg); |
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} |
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nunflshed++; /* lie */ |
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ambsync(); |
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} |
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|
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|
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ambnotify(obj) /* record new modifier */ |
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OBJECT obj; |
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{ |
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static int hitlimit = 0; |
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register OBJREC *o = objptr(obj); |
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register char **amblp; |
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|
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if (hitlimit || !ismodifier(o->otype)) |
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return; |
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for (amblp = amblist; *amblp != NULL; amblp++) |
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if (!strcmp(o->oname, *amblp)) { |
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if (ambset[0] >= MAXASET) { |
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error(WARNING, "too many modifiers in ambient list"); |
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hitlimit++; |
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return; /* should this be fatal? */ |
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} |
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insertelem(ambset, obj); |
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return; |
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} |
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} |
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|
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|
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ambient(acol, r) /* compute ambient component for ray */ |
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COLOR acol; |
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register RAY *r; |
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{ |
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static int rdepth = 0; /* ambient recursion */ |
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double d; |
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|
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if (ambdiv <= 0) /* no ambient calculation */ |
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goto dumbamb; |
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/* check number of bounces */ |
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if (rdepth >= ambounce) |
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goto dumbamb; |
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/* check ambient list */ |
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if (ambincl != -1 && r->ro != NULL && |
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ambincl != inset(ambset, r->ro->omod)) |
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goto dumbamb; |
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|
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if (ambacc <= FTINY) { /* no ambient storage */ |
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rdepth++; |
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d = doambient(acol, r, r->rweight, NULL, NULL); |
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rdepth--; |
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if (d == 0.0) |
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goto dumbamb; |
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return; |
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} |
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/* get ambient value */ |
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setcolor(acol, 0.0, 0.0, 0.0); |
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d = sumambient(acol, r, rdepth, |
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&atrunk, thescene.cuorg, thescene.cusize); |
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if (d > FTINY) |
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scalecolor(acol, 1.0/d); |
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else { |
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d = makeambient(acol, r, rdepth++); |
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rdepth--; |
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} |
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if (d > FTINY) |
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return; |
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dumbamb: /* return global value */ |
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copycolor(acol, ambval); |
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} |
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|
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|
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double |
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sumambient(acol, r, al, at, c0, s) /* get interpolated ambient value */ |
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COLOR acol; |
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register RAY *r; |
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int al; |
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AMBTREE *at; |
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FVECT c0; |
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double s; |
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{ |
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double d, e1, e2, wt, wsum; |
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COLOR ct; |
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FVECT ck0; |
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int i; |
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register int j; |
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register AMBVAL *av; |
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/* do this node */ |
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wsum = 0.0; |
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for (av = at->alist; av != NULL; av = av->next) { |
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/* |
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* Ambient level test. |
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*/ |
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if (av->lvl > al) /* list sorted, so this works */ |
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break; |
219 |
if (av->weight < r->rweight-FTINY) |
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continue; |
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/* |
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* Ambient radius test. |
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*/ |
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e1 = 0.0; |
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for (j = 0; j < 3; j++) { |
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d = av->pos[j] - r->rop[j]; |
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e1 += d * d; |
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} |
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e1 /= av->rad * av->rad; |
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if (e1 > ambacc*ambacc*1.21) |
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continue; |
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/* |
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* Normal direction test. |
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*/ |
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e2 = (1.0 - DOT(av->dir, r->ron)) * r->rweight; |
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if (e2 < 0.0) e2 = 0.0; |
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if (e1 + e2 > ambacc*ambacc*1.21) |
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continue; |
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/* |
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* Ray behind test. |
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*/ |
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d = 0.0; |
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for (j = 0; j < 3; j++) |
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d += (r->rop[j] - av->pos[j]) * |
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(av->dir[j] + r->ron[j]); |
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if (d*0.5 < -minarad*ambacc-.001) |
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continue; |
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/* |
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* Jittering final test reduces image artifacts. |
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*/ |
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wt = sqrt(e1) + sqrt(e2); |
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wt *= .9 + .2*urand(9015+samplendx); |
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if (wt > ambacc) |
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continue; |
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if (wt <= 1e-3) |
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wt = 1e3; |
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else |
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wt = 1.0 / wt; |
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wsum += wt; |
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extambient(ct, av, r->rop, r->ron); |
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scalecolor(ct, wt); |
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addcolor(acol, ct); |
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} |
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if (at->kid == NULL) |
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return(wsum); |
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/* do children */ |
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s *= 0.5; |
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for (i = 0; i < 8; i++) { |
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for (j = 0; j < 3; j++) { |
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ck0[j] = c0[j]; |
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if (1<<j & i) |
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ck0[j] += s; |
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if (r->rop[j] < ck0[j] - OCTSCALE*s) |
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break; |
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if (r->rop[j] > ck0[j] + (1.0+OCTSCALE)*s) |
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break; |
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} |
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if (j == 3) |
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wsum += sumambient(acol, r, al, at->kid+i, ck0, s); |
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} |
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return(wsum); |
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} |
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|
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|
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double |
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makeambient(acol, r, al) /* make a new ambient value */ |
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COLOR acol; |
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register RAY *r; |
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int al; |
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{ |
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AMBVAL amb; |
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FVECT gp, gd; |
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/* compute weight */ |
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amb.weight = pow(AVGREFL, (double)al); |
295 |
if (r->rweight < 0.2*amb.weight) /* heuristic */ |
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amb.weight = r->rweight; |
297 |
/* compute ambient */ |
298 |
amb.rad = doambient(acol, r, amb.weight, gp, gd); |
299 |
if (amb.rad == 0.0) |
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return(0.0); |
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/* store it */ |
302 |
VCOPY(amb.pos, r->rop); |
303 |
VCOPY(amb.dir, r->ron); |
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amb.lvl = al; |
305 |
copycolor(amb.val, acol); |
306 |
VCOPY(amb.gpos, gp); |
307 |
VCOPY(amb.gdir, gd); |
308 |
/* insert into tree */ |
309 |
avsave(&amb); /* and save to file */ |
310 |
return(amb.rad); |
311 |
} |
312 |
|
313 |
|
314 |
extambient(cr, ap, pv, nv) /* extrapolate value at pv, nv */ |
315 |
COLOR cr; |
316 |
register AMBVAL *ap; |
317 |
FVECT pv, nv; |
318 |
{ |
319 |
FVECT v1, v2; |
320 |
register int i; |
321 |
double d; |
322 |
|
323 |
d = 1.0; /* zeroeth order */ |
324 |
/* gradient due to translation */ |
325 |
for (i = 0; i < 3; i++) |
326 |
d += ap->gpos[i]*(pv[i]-ap->pos[i]); |
327 |
/* gradient due to rotation */ |
328 |
VCOPY(v1, ap->dir); |
329 |
fcross(v2, v1, nv); |
330 |
d += DOT(ap->gdir, v2); |
331 |
if (d <= 0.0) { |
332 |
setcolor(cr, 0.0, 0.0, 0.0); |
333 |
return; |
334 |
} |
335 |
copycolor(cr, ap->val); |
336 |
scalecolor(cr, d); |
337 |
} |
338 |
|
339 |
|
340 |
static |
341 |
initambfile(creat) /* initialize ambient file */ |
342 |
int creat; |
343 |
{ |
344 |
extern char *progname, *octname, VersionID[]; |
345 |
|
346 |
#ifdef F_SETLKW |
347 |
aflock(creat ? F_WRLCK : F_RDLCK); |
348 |
#endif |
349 |
#ifdef MSDOS |
350 |
setmode(fileno(ambfp), O_BINARY); |
351 |
#endif |
352 |
setbuf(ambfp, bmalloc(BUFSIZ+8)); |
353 |
if (creat) { /* new file */ |
354 |
newheader("RADIANCE", ambfp); |
355 |
fprintf(ambfp, "%s -av %g %g %g -ab %d -aa %g ", |
356 |
progname, colval(ambval,RED), |
357 |
colval(ambval,GRN), colval(ambval,BLU), |
358 |
ambounce, ambacc); |
359 |
fprintf(ambfp, "-ad %d -as %d -ar %d %s\n", |
360 |
ambdiv, ambssamp, ambres, |
361 |
octname==NULL ? "" : octname); |
362 |
fprintf(ambfp, "SOFTWARE= %s\n", VersionID); |
363 |
fputformat(AMBFMT, ambfp); |
364 |
putc('\n', ambfp); |
365 |
putambmagic(ambfp); |
366 |
} else if (checkheader(ambfp, AMBFMT, NULL) < 0 || !hasambmagic(ambfp)) |
367 |
error(USER, "bad ambient file"); |
368 |
} |
369 |
|
370 |
|
371 |
static |
372 |
avsave(av) /* insert and save an ambient value */ |
373 |
AMBVAL *av; |
374 |
{ |
375 |
avinsert(avstore(av)); |
376 |
if (ambfp == NULL) |
377 |
return; |
378 |
if (writambval(av, ambfp) < 0) |
379 |
goto writerr; |
380 |
if (++nunflshed >= AMBFLUSH) |
381 |
if (ambsync() == EOF) |
382 |
goto writerr; |
383 |
return; |
384 |
writerr: |
385 |
error(SYSTEM, "error writing ambient file"); |
386 |
} |
387 |
|
388 |
|
389 |
static AMBVAL * |
390 |
avstore(aval) /* allocate memory and store aval */ |
391 |
register AMBVAL *aval; |
392 |
{ |
393 |
register AMBVAL *av; |
394 |
|
395 |
if ((av = newambval()) == NULL) |
396 |
error(SYSTEM, "out of memory in avstore"); |
397 |
copystruct(av, aval); |
398 |
return(av); |
399 |
} |
400 |
|
401 |
|
402 |
static |
403 |
avinsert(av) /* insert ambient value in our tree */ |
404 |
register AMBVAL *av; |
405 |
{ |
406 |
register AMBTREE *at; |
407 |
register AMBVAL *ap; |
408 |
AMBVAL avh; |
409 |
FVECT ck0; |
410 |
double s; |
411 |
int branch; |
412 |
register int i; |
413 |
|
414 |
if (av->rad <= FTINY) |
415 |
error(CONSISTENCY, "zero ambient radius in avinsert"); |
416 |
at = &atrunk; |
417 |
VCOPY(ck0, thescene.cuorg); |
418 |
s = thescene.cusize; |
419 |
while (s*(OCTSCALE/2) > av->rad*ambacc) { |
420 |
if (at->kid == NULL) |
421 |
if ((at->kid = newambtree()) == NULL) |
422 |
error(SYSTEM, "out of memory in avinsert"); |
423 |
s *= 0.5; |
424 |
branch = 0; |
425 |
for (i = 0; i < 3; i++) |
426 |
if (av->pos[i] > ck0[i] + s) { |
427 |
ck0[i] += s; |
428 |
branch |= 1 << i; |
429 |
} |
430 |
at = at->kid + branch; |
431 |
} |
432 |
avh.next = at->alist; /* order by increasing level */ |
433 |
for (ap = &avh; ap->next != NULL; ap = ap->next) |
434 |
if (ap->next->lvl >= av->lvl) |
435 |
break; |
436 |
av->next = ap->next; |
437 |
ap->next = av; |
438 |
at->alist = avh.next; |
439 |
} |
440 |
|
441 |
|
442 |
static |
443 |
loadatree(at) /* move tree to main store */ |
444 |
register AMBTREE *at; |
445 |
{ |
446 |
register AMBVAL *av; |
447 |
register int i; |
448 |
/* transfer values at this node */ |
449 |
for (av = at->alist; av != NULL; av = at->alist) { |
450 |
at->alist = av->next; |
451 |
avinsert(av); |
452 |
} |
453 |
if (at->kid == NULL) |
454 |
return; |
455 |
for (i = 0; i < 8; i++) /* transfer and free children */ |
456 |
loadatree(at->kid+i); |
457 |
freeambtree(at->kid); |
458 |
} |
459 |
|
460 |
|
461 |
#ifdef F_SETLKW |
462 |
|
463 |
static |
464 |
aflock(typ) /* lock/unlock ambient file */ |
465 |
int typ; |
466 |
{ |
467 |
static struct flock fls; /* static so initialized to zeroes */ |
468 |
|
469 |
fls.l_type = typ; |
470 |
if (fcntl(fileno(ambfp), F_SETLKW, &fls) < 0) |
471 |
error(SYSTEM, "cannot (un)lock ambient file"); |
472 |
} |
473 |
|
474 |
|
475 |
int |
476 |
ambsync() /* synchronize ambient file */ |
477 |
{ |
478 |
static FILE *ambinp = NULL; |
479 |
static long lastpos = -1; |
480 |
long flen; |
481 |
AMBVAL avs; |
482 |
register int n; |
483 |
|
484 |
if (nunflshed == 0) |
485 |
return(0); |
486 |
if (lastpos < 0) /* initializing (locked in initambfile) */ |
487 |
goto syncend; |
488 |
/* gain exclusive access */ |
489 |
aflock(F_WRLCK); |
490 |
/* see if file has grown */ |
491 |
if ((flen = lseek(fileno(ambfp), 0L, 2)) < 0) |
492 |
goto seekerr; |
493 |
if (n = flen - lastpos) { /* file has grown */ |
494 |
if (ambinp == NULL) { /* use duplicate filedes */ |
495 |
ambinp = fdopen(dup(fileno(ambfp)), "r"); |
496 |
if (ambinp == NULL) |
497 |
error(SYSTEM, "fdopen failed in ambsync"); |
498 |
} |
499 |
if (fseek(ambinp, lastpos, 0) < 0) |
500 |
goto seekerr; |
501 |
while (n >= AMBVALSIZ) { /* load contributed values */ |
502 |
readambval(&avs, ambinp); |
503 |
avinsert(avstore(&avs)); |
504 |
n -= AMBVALSIZ; |
505 |
} |
506 |
/*** seek always as safety measure |
507 |
if (n) ***/ /* alignment */ |
508 |
if (lseek(fileno(ambfp), flen-n, 0) < 0) |
509 |
goto seekerr; |
510 |
} |
511 |
#ifdef DEBUG |
512 |
if (ambfp->_ptr - ambfp->_base != nunflshed*AMBVALSIZ) { |
513 |
sprintf(errmsg, "ambient file buffer at %d rather than %d", |
514 |
ambfp->_ptr - ambfp->_base, |
515 |
nunflshed*AMBVALSIZ); |
516 |
error(CONSISTENCY, errmsg); |
517 |
} |
518 |
#endif |
519 |
syncend: |
520 |
n = fflush(ambfp); /* calls write() at last */ |
521 |
if ((lastpos = lseek(fileno(ambfp), 0L, 1)) < 0) |
522 |
goto seekerr; |
523 |
aflock(F_UNLCK); /* release file */ |
524 |
nunflshed = 0; |
525 |
return(n); |
526 |
seekerr: |
527 |
error(SYSTEM, "seek failed in ambsync"); |
528 |
} |
529 |
|
530 |
#else |
531 |
|
532 |
int |
533 |
ambsync() /* flush ambient file */ |
534 |
{ |
535 |
if (nunflshed == 0) |
536 |
return(0); |
537 |
nunflshed = 0; |
538 |
return(fflush(ambfp)); |
539 |
} |
540 |
|
541 |
#endif |