src/rt/rpict.c

/* Copyright (c) 1996 Regents of the University of California */

#ifndef lint
static char SCCSid[] = "$SunId$ LBL";
#endif

/*
 *  rpict.c - routines and variables for picture generation.
 */

#include  "ray.h"

#include  <sys/types.h>

#ifndef NIX
#ifdef BSD
#include  <sys/time.h>
#include  <sys/resource.h>
#else
#include  <sys/times.h>
#include  <unistd.h>
#endif
#endif

extern time_t   time();

#include  <signal.h>

#include  "view.h"

#include  "resolu.h"

#include  "random.h"

#include  "paths.h"

#define  RFTEMPLATE     "rfXXXXXX"

#ifndef SIGCONT
#define SIGCONT         SIGIO
#endif

int  dimlist[MAXDIM];                   /* sampling dimensions */
int  ndims = 0;                         /* number of sampling dimensions */
int  samplendx;                         /* sample index number */

VIEW  ourview = STDVIEW;                /* view parameters */
int  hresolu = 512;                     /* horizontal resolution */
int  vresolu = 512;                     /* vertical resolution */
double  pixaspect = 1.0;                /* pixel aspect ratio */

int  psample = 4;                       /* pixel sample size */
double  maxdiff = .05;                  /* max. difference for interpolation */
double  dstrpix = 0.67;                 /* square pixel distribution */

double  dstrsrc = 0.0;                  /* square source distribution */
double  shadthresh = .05;               /* shadow threshold */
double  shadcert = .5;                  /* shadow certainty */
int  directrelay = 1;                   /* number of source relays */
int  vspretest = 512;                   /* virtual source pretest density */
int  directvis = 1;                     /* sources visible? */
double  srcsizerat = .25;               /* maximum ratio source size/dist. */

COLOR  cextinction = BLKCOLOR;          /* global extinction coefficient */
COLOR  salbedo = BLKCOLOR;              /* global scattering albedo */
double  seccg = 0.;                     /* global scattering eccentricity */
double  ssampdist = 0.;                 /* scatter sampling distance */

double  specthresh = .15;               /* specular sampling threshold */
double  specjitter = 1.;                /* specular sampling jitter */

int  backvis = 1;                       /* back face visibility */

int  maxdepth = 6;                      /* maximum recursion depth */
double  minweight = 5e-3;               /* minimum ray weight */

COLOR  ambval = BLKCOLOR;               /* ambient value */
int  ambvwt = 0;                        /* initial weight for ambient value */
double  ambacc = 0.2;                   /* ambient accuracy */
int  ambres = 32;                       /* ambient resolution */
int  ambdiv = 128;                      /* ambient divisions */
int  ambssamp = 0;                      /* ambient super-samples */
int  ambounce = 0;                      /* ambient bounces */
char  *amblist[128];                    /* ambient include/exclude list */
int  ambincl = -1;                      /* include == 1, exclude == 0 */

#ifdef MSDOS
int  ralrm = 60;                        /* seconds between reports */
#else
int  ralrm = 0;                         /* seconds between reports */
#endif

double  pctdone = 0.0;                  /* percentage done */

time_t  tlastrept = 0L;                 /* time at last report */

extern time_t  tstart;                  /* starting time */

extern unsigned long  nrays;            /* number of rays traced */

#define  MAXDIV         16              /* maximum sample size */

#define  pixjitter()    (.5+dstrpix*(.5-frandom()))

int  hres, vres;                        /* resolution for this frame */

extern char  *mktemp();

double  pixvalue();

#ifdef NIX
#define  file_exists(f) (access(f,F_OK)==0)
#else
#include  <sys/types.h>
#include  <sys/stat.h>
int
file_exists(fname)                              /* ordinary file exists? */
char  *fname;
{
        struct stat  sbuf;
        if (stat(fname, &sbuf) < 0) return(0);
        return((sbuf.st_mode & S_IFREG) != 0);
}
#endif


quit(code)                      /* quit program */
int  code;
{
        if (code)                       /* report status */
                report();
        headclean();                    /* delete header file */
        pfclean();                      /* clean up persist files */
        exit(code);
}


#ifndef NIX
report()                /* report progress */
{
        extern char  *myhostname();
        double  u, s;
#ifdef BSD
        struct rusage  rubuf;
#else
        struct tms  tbuf;
        double  period;
#endif

        tlastrept = time((time_t *)NULL);
#ifdef BSD
        getrusage(RUSAGE_SELF, &rubuf);
        u = rubuf.ru_utime.tv_sec + rubuf.ru_utime.tv_usec/1e6;
        s = rubuf.ru_stime.tv_sec + rubuf.ru_stime.tv_usec/1e6;
        getrusage(RUSAGE_CHILDREN, &rubuf);
        u += rubuf.ru_utime.tv_sec + rubuf.ru_utime.tv_usec/1e6;
        s += rubuf.ru_stime.tv_sec + rubuf.ru_stime.tv_usec/1e6;
#else
        times(&tbuf);
#ifdef _SC_CLK_TCK
        period = 1.0 / sysconf(_SC_CLK_TCK);
#else
        period = 1.0 / 60.0;
#endif
        u = ( tbuf.tms_utime + tbuf.tms_cutime ) * period;
        s = ( tbuf.tms_stime + tbuf.tms_cstime ) * period;
#endif

        sprintf(errmsg,
                "%lu rays, %4.2f%% after %.3fu %.3fs %.3fr hours on %s\n",
                        nrays, pctdone, u/3600., s/3600.,
                        (tlastrept-tstart)/3600., myhostname());
        eputs(errmsg);
#ifndef BSD
        signal(SIGCONT, report);
#endif
}
#else
report()                /* report progress */
{
        tlastrept = time((time_t *)NULL);
        sprintf(errmsg, "%lu rays, %4.2f%% after %5.4f hours\n",
                        nrays, pctdone, (tlastrept-tstart)/3600.0);
        eputs(errmsg);
}
#endif


rpict(seq, pout, zout, prvr)                    /* generate image(s) */
int  seq;
char  *pout, *zout, *prvr;
/*
 * If seq is greater than zero, then we will render a sequence of
 * images based on view parameter strings read from the standard input.
 * If pout is NULL, then all images will be sent to the standard ouput.
 * If seq is greater than zero and prvr is an integer, then it is the
 * frame number at which rendering should begin.  Preceeding view parameter
 * strings will be skipped in the input.
 * If pout and prvr are the same, prvr is renamed to avoid overwriting.
 * Note that pout and zout should contain %d format specifications for
 * sequenced file naming.
 */
{
        extern char  *rindex(), *strncpy(), *strcat(), *strcpy();
        char  fbuf[128], fbuf2[128];
        int  npicts;
        register char  *cp;
        RESOLU  rs;
        double  pa;
                                        /* check sampling */
        if (psample < 1)
                psample = 1;
        else if (psample > MAXDIV) {
                sprintf(errmsg, "pixel sampling reduced from %d to %d",
                                psample, MAXDIV);
                error(WARNING, errmsg);
                psample = MAXDIV;
        }
                                        /* get starting frame */
        if (seq <= 0)
                seq = 0;
        else if (prvr != NULL && isint(prvr)) {
                register int  rn;               /* skip to specified view */
                if ((rn = atoi(prvr)) < seq)
                        error(USER, "recover frame less than start frame");
                if (pout == NULL)
                        error(USER, "missing output file specification");
                for ( ; seq < rn; seq++)
                        if (nextview(stdin) == EOF)
                                error(USER, "unexpected EOF on view input");
                prvr = fbuf;                    /* mark for renaming */
        }
        if (pout != NULL & prvr != NULL) {
                sprintf(fbuf, pout, seq);
                if (!strcmp(prvr, fbuf)) {      /* rename */
                        strcpy(fbuf2, fbuf);
                        for (cp = fbuf2; *cp; cp++)
                                ;
                        while (cp > fbuf2 && !ISDIRSEP(cp[-1]))
                                cp--;
                        strcpy(cp, RFTEMPLATE);
                        prvr = mktemp(fbuf2);
                        if (rename(fbuf, prvr) < 0)
                                if (errno == ENOENT) {  /* ghost file */
                                        sprintf(errmsg,
                                                "new output file \"%s\"",
                                                fbuf);
                                        error(WARNING, errmsg);
                                        prvr = NULL;
                                } else {                /* serious error */
                                        sprintf(errmsg,
                                        "cannot rename \"%s\" to \"%s\"",
                                                fbuf, prvr);
                                        error(SYSTEM, errmsg);
                                }
                }
        }
        npicts = 0;                     /* render sequence */
        do {
                if (seq && nextview(stdin) == EOF)
                        break;
                pctdone = 0.0;
                if (pout != NULL) {
                        sprintf(fbuf, pout, seq);
                        if (file_exists(fbuf)) {
                                if (prvr != NULL || !strcmp(fbuf, pout)) {
                                        sprintf(errmsg,
                                                "output file \"%s\" exists",
                                                fbuf);
                                        error(USER, errmsg);
                                }
                                continue;               /* don't clobber */
                        }
                        if (freopen(fbuf, "w", stdout) == NULL) {
                                sprintf(errmsg,
                                        "cannot open output file \"%s\"", fbuf);
                                error(SYSTEM, errmsg);
                        }
#ifdef MSDOS
                        setmode(fileno(stdout), O_BINARY);
#endif
                        dupheader();
                }
                hres = hresolu; vres = vresolu; pa = pixaspect;
                if (prvr != NULL)
                        if (viewfile(prvr, &ourview, &rs) <= 0
                                        || rs.or != PIXSTANDARD) {
                                sprintf(errmsg,
                        "cannot recover view parameters from \"%s\"", prvr);
                                error(WARNING, errmsg);
                        } else {
                                pa = 0.0;
                                hres = scanlen(&rs);
                                vres = numscans(&rs);
                        }
                if ((cp = setview(&ourview)) != NULL)
                        error(USER, cp);
                normaspect(viewaspect(&ourview), &pa, &hres, &vres);
                if (seq) {
                        if (ralrm > 0) {
                                fprintf(stderr, "FRAME %d:", seq);
                                fprintview(&ourview, stderr);
                                putc('\n', stderr);
                                fflush(stderr);
                        }
                        printf("FRAME=%d\n", seq);
                }
                fputs(VIEWSTR, stdout);
                fprintview(&ourview, stdout);
                putchar('\n');
                if (pa < .99 || pa > 1.01)
                        fputaspect(pa, stdout);
                fputformat(COLRFMT, stdout);
                putchar('\n');
                if (zout != NULL)
                        sprintf(cp=fbuf, zout, seq);
                else
                        cp = NULL;
                render(cp, prvr);
                prvr = NULL;
                npicts++;
        } while (seq++);
                                        /* check that we did something */
        if (npicts == 0)
                error(WARNING, "no output produced");
}


nextview(fp)                            /* get next view from fp */
FILE  *fp;
{
        char  linebuf[256];

        while (fgets(linebuf, sizeof(linebuf), fp) != NULL)
                if (isview(linebuf) && sscanview(&ourview, linebuf) > 0)
                        return(0);
        return(EOF);
}       


render(zfile, oldfile)                          /* render the scene */
char  *zfile, *oldfile;
{
        extern long  lseek();
        COLOR  *scanbar[MAXDIV+1];      /* scanline arrays of pixel values */
        float  *zbar[MAXDIV+1];         /* z values */
        char  *sampdens;                /* previous sample density */
        int  ypos;                      /* current scanline */
        int  ystep;                     /* current y step size */
        int  hstep;                     /* h step size */
        int  zfd;
        COLOR  *colptr;
        float  *zptr;
        register int  i;
                                        /* allocate scanlines */
        for (i = 0; i <= psample; i++) {
                scanbar[i] = (COLOR *)malloc(hres*sizeof(COLOR));
                if (scanbar[i] == NULL)
                        goto memerr;
        }
        hstep = (psample*140+49)/99;            /* quincunx sampling */
        ystep = (psample*99+70)/140;
        if (hstep > 2) {
                i = hres/hstep + 2;
                if ((sampdens = malloc(i)) == NULL)
                        goto memerr;
                while (i--)
                        sampdens[i] = hstep;
        } else
                sampdens = NULL;
                                        /* open z-file */
        if (zfile != NULL) {
                if ((zfd = open(zfile, O_WRONLY|O_CREAT, 0666)) == -1) {
                        sprintf(errmsg, "cannot open z-file \"%s\"", zfile);
                        error(SYSTEM, errmsg);
                }
#ifdef MSDOS
                setmode(zfd, O_BINARY);
#endif
                for (i = 0; i <= psample; i++) {
                        zbar[i] = (float *)malloc(hres*sizeof(float));
                        if (zbar[i] == NULL)
                                goto memerr;
                }
        } else {
                zfd = -1;
                for (i = 0; i <= psample; i++)
                        zbar[i] = NULL;
        }
                                        /* write out boundaries */
        fprtresolu(hres, vres, stdout);
                                        /* recover file and compute first */
        i = salvage(oldfile);
        if (i >= vres)
                goto alldone;
        if (zfd != -1 && i > 0 &&
                        lseek(zfd, (long)i*hres*sizeof(float), 0) == -1)
                error(SYSTEM, "z-file seek error in render");
        pctdone = 100.0*i/vres;
        if (ralrm > 0)                  /* report init stats */
                report();
#ifndef  BSD
        else
#endif
        signal(SIGCONT, report);
        ypos = vres-1 - i;                      /* initialize sampling */
        if (directvis)
                init_drawsources(psample);
        fillscanline(scanbar[0], zbar[0], sampdens, hres, ypos, hstep);
                                                /* compute scanlines */
        for (ypos -= ystep; ypos > -ystep; ypos -= ystep) {
                                                        /* bottom adjust? */
                if (ypos < 0) {
                        ystep += ypos;
                        ypos = 0;
                }
                colptr = scanbar[ystep];                /* move base to top */
                scanbar[ystep] = scanbar[0];
                scanbar[0] = colptr;
                zptr = zbar[ystep];
                zbar[ystep] = zbar[0];
                zbar[0] = zptr;
                                                        /* fill base line */
                fillscanline(scanbar[0], zbar[0], sampdens,
                                hres, ypos, hstep);
                                                        /* fill bar */
                fillscanbar(scanbar, zbar, hres, ypos, ystep);
                if (directvis)                          /* add bitty sources */
                        drawsources(scanbar, zbar, 0, hres, ypos, ystep);
                                                        /* write it out */
#ifndef  BSD
                signal(SIGCONT, SIG_IGN);       /* don't interrupt writes */
#endif
                for (i = ystep; i > 0; i--) {
                        if (zfd != -1 && write(zfd, (char *)zbar[i],
                                        hres*sizeof(float))
                                        < hres*sizeof(float))
                                goto writerr;
                        if (fwritescan(scanbar[i], hres, stdout) < 0)
                                goto writerr;
                }
                if (fflush(stdout) == EOF)
                        goto writerr;
                                                        /* record progress */
                pctdone = 100.0*(vres-1-ypos)/vres;
                if (ralrm > 0 && time((time_t *)NULL) >= tlastrept+ralrm)
                        report();
#ifndef  BSD
                else
                        signal(SIGCONT, report);
#endif
        }
                                                /* clean up */
        signal(SIGCONT, SIG_IGN);
        if (zfd != -1 && write(zfd, (char *)zbar[0], hres*sizeof(float))
                                < hres*sizeof(float))
                goto writerr;
        fwritescan(scanbar[0], hres, stdout);
        if (fflush(stdout) == EOF)
                goto writerr;
alldone:
        if (zfd != -1) {
                if (close(zfd) == -1)
                        goto writerr;
                for (i = 0; i <= psample; i++)
                        free((char *)zbar[i]);
        }
        for (i = 0; i <= psample; i++)
                free((char *)scanbar[i]);
        if (sampdens != NULL)
                free(sampdens);
        pctdone = 100.0;
        if (ralrm > 0)
                report();
        signal(SIGCONT, SIG_DFL);
        return;
writerr:
        error(SYSTEM, "write error in render");
memerr:
        error(SYSTEM, "out of memory in render");
}


fillscanline(scanline, zline, sd, xres, y, xstep)       /* fill scan at y */
register COLOR  *scanline;
register float  *zline;
register char  *sd;
int  xres, y, xstep;
{
        static int  nc = 0;             /* number of calls */
        int  bl = xstep, b = xstep;
        double  z;
        register int  i;

        z = pixvalue(scanline[0], 0, y);
        if (zline) zline[0] = z;
                                /* zig-zag start for quincunx pattern */
        for (i = ++nc & 1 ? xstep : xstep/2; i < xres-1+xstep; i += xstep) {
                if (i >= xres) {
                        xstep += xres-1-i;
                        i = xres-1;
                }
                z = pixvalue(scanline[i], i, y);
                if (zline) zline[i] = z;
                if (sd) b = sd[0] > sd[1] ? sd[0] : sd[1];
                if (i <= xstep)
                        b = fillsample(scanline, zline, 0, y, i, 0, b/2);
                else
                        b = fillsample(scanline+i-xstep,
                                        zline ? zline+i-xstep : (float *)NULL,
                                        i-xstep, y, xstep, 0, b/2);
                if (sd) *sd++ = nc & 1 ? bl : b;
                bl = b;
        }
        if (sd && nc & 1) *sd = bl;
}


fillscanbar(scanbar, zbar, xres, y, ysize)      /* fill interior */
register COLOR  *scanbar[];
register float  *zbar[];
int  xres, y, ysize;
{
        COLOR  vline[MAXDIV+1];
        float  zline[MAXDIV+1];
        int  b = ysize;
        register int  i, j;

        for (i = 0; i < xres; i++) {
                copycolor(vline[0], scanbar[0][i]);
                copycolor(vline[ysize], scanbar[ysize][i]);
                if (zbar[0]) {
                        zline[0] = zbar[0][i];
                        zline[ysize] = zbar[ysize][i];
                }
                b = fillsample(vline, zbar[0] ? zline : (float *)NULL,
                                i, y, 0, ysize, b/2);

                for (j = 1; j < ysize; j++)
                        copycolor(scanbar[j][i], vline[j]);
                if (zbar[0])
                        for (j = 1; j < ysize; j++)
                                zbar[j][i] = zline[j];
        }
}


int
fillsample(colline, zline, x, y, xlen, ylen, b) /* fill interior points */
register COLOR  *colline;
register float  *zline;
int  x, y;
int  xlen, ylen;
int  b;
{
        double  ratio;
        double  z;
        COLOR  ctmp;
        int  ncut;
        register int  len;

        if (xlen > 0)                   /* x or y length is zero */
                len = xlen;
        else
                len = ylen;

        if (len <= 1)                   /* limit recursion */
                return(0);

        if (b > 0 ||
        (zline && 2.*fabs(zline[0]-zline[len]) > maxdiff*(zline[0]+zline[len]))
                        || bigdiff(colline[0], colline[len], maxdiff)) {

                z = pixvalue(colline[len>>1], x + (xlen>>1), y + (ylen>>1));
                if (zline) zline[len>>1] = z;
                ncut = 1;
        } else {                                        /* interpolate */
                copycolor(colline[len>>1], colline[len]);
                ratio = (double)(len>>1) / len;
                scalecolor(colline[len>>1], ratio);
                if (zline) zline[len>>1] = zline[len] * ratio;
                ratio = 1.0 - ratio;
                copycolor(ctmp, colline[0]);
                scalecolor(ctmp, ratio);
                addcolor(colline[len>>1], ctmp);
                if (zline) zline[len>>1] += zline[0] * ratio;
                ncut = 0;
        }
                                                        /* recurse */
        ncut += fillsample(colline, zline, x, y, xlen>>1, ylen>>1, (b-1)/2);

        ncut += fillsample(colline+(len>>1),
                        zline ? zline+(len>>1) : (float *)NULL,
                        x+(xlen>>1), y+(ylen>>1),
                        xlen-(xlen>>1), ylen-(ylen>>1), b/2);

        return(ncut);
}


double
pixvalue(col, x, y)             /* compute pixel value */
COLOR  col;                     /* returned color */
int  x, y;                      /* pixel position */
{
        static RAY  thisray;

        if ((thisray.rmax = viewray(thisray.rorg, thisray.rdir, &ourview,
                        (x+pixjitter())/hres, (y+pixjitter())/vres)) < -FTINY) {
                setcolor(col, 0.0, 0.0, 0.0);
                return(0.0);
        }

        rayorigin(&thisray, NULL, PRIMARY, 1.0);

        samplendx = pixnumber(x,y,hres,vres);   /* set pixel index */

        rayvalue(&thisray);                     /* trace ray */

        copycolor(col, thisray.rcol);           /* return color */

        return(thisray.rt);                     /* return distance */
}


int
salvage(oldfile)                /* salvage scanlines from killed program */
char  *oldfile;
{
        COLR  *scanline;
        FILE  *fp;
        int  x, y;

        if (oldfile == NULL)
                goto gotzip;

        if ((fp = fopen(oldfile, "r")) == NULL) {
                sprintf(errmsg, "cannot open recover file \"%s\"", oldfile);
                error(WARNING, errmsg);
                goto gotzip;
        }
#ifdef MSDOS
        setmode(fileno(fp), O_BINARY);
#endif
                                /* discard header */
        getheader(fp, NULL, NULL);
                                /* get picture size */
        if (!fscnresolu(&x, &y, fp)) {
                sprintf(errmsg, "bad recover file \"%s\" - not removed",
                                oldfile);
                error(WARNING, errmsg);
                fclose(fp);
                goto gotzip;
        }

        if (x != hres || y != vres) {
                sprintf(errmsg, "resolution mismatch in recover file \"%s\"",
                                oldfile);
                error(USER, errmsg);
        }

        scanline = (COLR *)malloc(hres*sizeof(COLR));
        if (scanline == NULL)
                error(SYSTEM, "out of memory in salvage");
        for (y = 0; y < vres; y++) {
                if (freadcolrs(scanline, hres, fp) < 0)
                        break;
                if (fwritecolrs(scanline, hres, stdout) < 0)
                        goto writerr;
        }
        if (fflush(stdout) == EOF)
                goto writerr;
        free((char *)scanline);
        fclose(fp);
        unlink(oldfile);
        return(y);
gotzip:
        if (fflush(stdout) == EOF)
                error(SYSTEM, "error writing picture header");
        return(0);
writerr:
        sprintf(errmsg, "write error during recovery of \"%s\"", oldfile);
        error(SYSTEM, errmsg);
}


int
pixnumber(x, y, xres, yres)             /* compute pixel index (brushed) */
register int  x, y;
int  xres, yres;
{
        x -= y;
        while (x < 0)
                x += xres;
        return((((x>>2)*yres + y) << 2) + (x & 3));
}
Revision:	2.48
Committed:	Mon Oct 20 16:46:37 1997 UTC (26 years, 6 months ago) by gregl
Content type:	text/plain
Branch:	MAIN
Changes since 2.47:	+4 -3 lines
Log Message:	added test of directvis before call to drawsources()
#	User	Rev	Content
1	greg	2.47	/* Copyright (c) 1996 Regents of the University of California */
2	greg	1.1
3			#ifndef lint
4			static char SCCSid[] = "$SunId$ LBL";
5			#endif
6
7			/*
8			* rpict.c - routines and variables for picture generation.
9			*/
10
11			#include "ray.h"
12
13	greg	2.32	#include <sys/types.h>
14
15	greg	2.30	#ifndef NIX
16	greg	1.1	#ifdef BSD
17			#include <sys/time.h>
18			#include <sys/resource.h>
19	greg	2.30	#else
20			#include <sys/times.h>
21	greg	2.33	#include <unistd.h>
22	greg	1.34	#endif
23	greg	2.30	#endif
24	greg	1.34
25	greg	2.32	extern time_t time();
26
27	greg	1.14	#include <signal.h>
28	greg	1.1
29			#include "view.h"
30
31	greg	1.36	#include "resolu.h"
32
33	greg	1.1	#include "random.h"
34
35	greg	2.12	#include "paths.h"
36
37	greg	2.21	#define RFTEMPLATE "rfXXXXXX"
38
39	greg	2.22	#ifndef SIGCONT
40			#define SIGCONT SIGIO
41			#endif
42
43	greg	1.25	int dimlist[MAXDIM]; /* sampling dimensions */
44			int ndims = 0; /* number of sampling dimensions */
45			int samplendx; /* sample index number */
46
47	greg	1.12	VIEW ourview = STDVIEW; /* view parameters */
48			int hresolu = 512; /* horizontal resolution */
49			int vresolu = 512; /* vertical resolution */
50	greg	2.14	double pixaspect = 1.0; /* pixel aspect ratio */
51	greg	1.1
52			int psample = 4; /* pixel sample size */
53	greg	2.14	double maxdiff = .05; /* max. difference for interpolation */
54			double dstrpix = 0.67; /* square pixel distribution */
55	greg	1.1
56	greg	2.14	double dstrsrc = 0.0; /* square source distribution */
57			double shadthresh = .05; /* shadow threshold */
58			double shadcert = .5; /* shadow certainty */
59	greg	1.35	int directrelay = 1; /* number of source relays */
60	greg	1.29	int vspretest = 512; /* virtual source pretest density */
61	greg	2.20	int directvis = 1; /* sources visible? */
62	greg	2.14	double srcsizerat = .25; /* maximum ratio source size/dist. */
63	greg	2.41
64			COLOR cextinction = BLKCOLOR; /* global extinction coefficient */
65	greg	2.46	COLOR salbedo = BLKCOLOR; /* global scattering albedo */
66	greg	2.41	double seccg = 0.; /* global scattering eccentricity */
67			double ssampdist = 0.; /* scatter sampling distance */
68	greg	1.1
69	greg	2.14	double specthresh = .15; /* specular sampling threshold */
70			double specjitter = 1.; /* specular sampling jitter */
71	greg	2.5
72	greg	2.40	int backvis = 1; /* back face visibility */
73
74	greg	1.1	int maxdepth = 6; /* maximum recursion depth */
75	greg	2.14	double minweight = 5e-3; /* minimum ray weight */
76	greg	1.1
77			COLOR ambval = BLKCOLOR; /* ambient value */
78	greg	2.44	int ambvwt = 0; /* initial weight for ambient value */
79	greg	2.14	double ambacc = 0.2; /* ambient accuracy */
80	greg	1.6	int ambres = 32; /* ambient resolution */
81	greg	1.1	int ambdiv = 128; /* ambient divisions */
82			int ambssamp = 0; /* ambient super-samples */
83			int ambounce = 0; /* ambient bounces */
84			char amblist[128]; / ambient include/exclude list */
85			int ambincl = -1; /* include == 1, exclude == 0 */
86
87	greg	2.16	#ifdef MSDOS
88			int ralrm = 60; /* seconds between reports */
89			#else
90	greg	1.1	int ralrm = 0; /* seconds between reports */
91	greg	2.16	#endif
92	greg	1.1
93	greg	2.14	double pctdone = 0.0; /* percentage done */
94	greg	1.1
95	greg	2.32	time_t tlastrept = 0L; /* time at last report */
96	greg	1.24
97	greg	2.32	extern time_t tstart; /* starting time */
98	greg	1.24
99	greg	2.24	extern unsigned long nrays; /* number of rays traced */
100	greg	1.1
101	greg	2.14	#define MAXDIV 16 /* maximum sample size */
102	greg	1.1
103	greg	2.14	#define pixjitter() (.5+dstrpix*(.5-frandom()))
104	greg	1.1
105	greg	2.47	int hres, vres; /* resolution for this frame */
106	greg	2.8
107			extern char *mktemp();
108
109	greg	2.14	double pixvalue();
110	greg	1.1
111	greg	2.27	#ifdef NIX
112			#define file_exists(f) (access(f,F_OK)==0)
113			#else
114			#include <sys/types.h>
115			#include <sys/stat.h>
116			int
117			file_exists(fname) /* ordinary file exists? */
118			char *fname;
119			{
120			struct stat sbuf;
121			if (stat(fname, &sbuf) < 0) return(0);
122			return((sbuf.st_mode & S_IFREG) != 0);
123			}
124			#endif
125	greg	1.11
126	greg	2.27
127	greg	1.1	quit(code) /* quit program */
128			int code;
129			{
130	greg	2.8	if (code) /* report status */
131	greg	1.1	report();
132	greg	2.21	headclean(); /* delete header file */
133			pfclean(); /* clean up persist files */
134	greg	1.1	exit(code);
135			}
136
137
138	greg	2.30	#ifndef NIX
139	greg	1.1	report() /* report progress */
140			{
141	greg	2.43	extern char *myhostname();
142	greg	2.30	double u, s;
143			#ifdef BSD
144	greg	1.1	struct rusage rubuf;
145	greg	2.30	#else
146			struct tms tbuf;
147	greg	2.33	double period;
148	greg	2.30	#endif
149	greg	1.1
150	greg	2.32	tlastrept = time((time_t *)NULL);
151	greg	2.30	#ifdef BSD
152	greg	1.1	getrusage(RUSAGE_SELF, &rubuf);
153	greg	2.30	u = rubuf.ru_utime.tv_sec + rubuf.ru_utime.tv_usec/1e6;
154			s = rubuf.ru_stime.tv_sec + rubuf.ru_stime.tv_usec/1e6;
155	greg	1.1	getrusage(RUSAGE_CHILDREN, &rubuf);
156	greg	2.30	u += rubuf.ru_utime.tv_sec + rubuf.ru_utime.tv_usec/1e6;
157			s += rubuf.ru_stime.tv_sec + rubuf.ru_stime.tv_usec/1e6;
158			#else
159			times(&tbuf);
160	greg	2.36	#ifdef _SC_CLK_TCK
161	greg	2.33	period = 1.0 / sysconf(_SC_CLK_TCK);
162	greg	2.36	#else
163			period = 1.0 / 60.0;
164			#endif
165	greg	2.33	u = ( tbuf.tms_utime + tbuf.tms_cutime ) * period;
166			s = ( tbuf.tms_stime + tbuf.tms_cstime ) * period;
167	greg	2.30	#endif
168	greg	1.1
169	greg	2.30	sprintf(errmsg,
170			"%lu rays, %4.2f%% after %.3fu %.3fs %.3fr hours on %s\n",
171			nrays, pctdone, u/3600., s/3600.,
172	greg	2.43	(tlastrept-tstart)/3600., myhostname());
173	greg	1.24	eputs(errmsg);
174	greg	2.35	#ifndef BSD
175			signal(SIGCONT, report);
176			#endif
177	greg	1.24	}
178	greg	1.1	#else
179	greg	1.24	report() /* report progress */
180			{
181	greg	2.32	tlastrept = time((time_t *)NULL);
182	greg	2.30	sprintf(errmsg, "%lu rays, %4.2f%% after %5.4f hours\n",
183	greg	1.24	nrays, pctdone, (tlastrept-tstart)/3600.0);
184	greg	1.1	eputs(errmsg);
185			}
186	greg	1.24	#endif
187	greg	1.1
188
189	greg	2.8	rpict(seq, pout, zout, prvr) /* generate image(s) */
190			int seq;
191			char pout, zout, *prvr;
192			/*
193			* If seq is greater than zero, then we will render a sequence of
194			* images based on view parameter strings read from the standard input.
195			* If pout is NULL, then all images will be sent to the standard ouput.
196			* If seq is greater than zero and prvr is an integer, then it is the
197			* frame number at which rendering should begin. Preceeding view parameter
198			* strings will be skipped in the input.
199			* If pout and prvr are the same, prvr is renamed to avoid overwriting.
200			* Note that pout and zout should contain %d format specifications for
201			* sequenced file naming.
202			*/
203			{
204	greg	2.21	extern char rindex(), strncpy(), strcat(), strcpy();
205	greg	2.9	char fbuf[128], fbuf2[128];
206	greg	2.26	int npicts;
207	greg	2.9	register char *cp;
208	greg	2.14	RESOLU rs;
209			double pa;
210	greg	2.8	/* check sampling */
211			if (psample < 1)
212			psample = 1;
213			else if (psample > MAXDIV) {
214			sprintf(errmsg, "pixel sampling reduced from %d to %d",
215			psample, MAXDIV);
216			error(WARNING, errmsg);
217			psample = MAXDIV;
218			}
219			/* get starting frame */
220			if (seq <= 0)
221			seq = 0;
222			else if (prvr != NULL && isint(prvr)) {
223	greg	2.9	register int rn; /* skip to specified view */
224	greg	2.8	if ((rn = atoi(prvr)) < seq)
225			error(USER, "recover frame less than start frame");
226			if (pout == NULL)
227			error(USER, "missing output file specification");
228			for ( ; seq < rn; seq++)
229			if (nextview(stdin) == EOF)
230			error(USER, "unexpected EOF on view input");
231			prvr = fbuf; /* mark for renaming */
232			}
233	greg	2.18	if (pout != NULL & prvr != NULL) {
234	greg	2.8	sprintf(fbuf, pout, seq);
235	greg	2.18	if (!strcmp(prvr, fbuf)) { /* rename */
236			strcpy(fbuf2, fbuf);
237			for (cp = fbuf2; *cp; cp++)
238			;
239			while (cp > fbuf2 && !ISDIRSEP(cp[-1]))
240			cp--;
241			strcpy(cp, RFTEMPLATE);
242	greg	2.8	prvr = mktemp(fbuf2);
243	greg	2.28	if (rename(fbuf, prvr) < 0)
244			if (errno == ENOENT) { /* ghost file */
245			sprintf(errmsg,
246			"new output file \"%s\"",
247			fbuf);
248			error(WARNING, errmsg);
249			prvr = NULL;
250			} else { /* serious error */
251			sprintf(errmsg,
252	greg	2.8	"cannot rename \"%s\" to \"%s\"",
253			fbuf, prvr);
254	greg	2.28	error(SYSTEM, errmsg);
255			}
256	greg	2.8	}
257			}
258	greg	2.26	npicts = 0; /* render sequence */
259	greg	2.8	do {
260			if (seq && nextview(stdin) == EOF)
261			break;
262	greg	2.25	pctdone = 0.0;
263	greg	2.8	if (pout != NULL) {
264			sprintf(fbuf, pout, seq);
265	greg	2.27	if (file_exists(fbuf)) {
266			if (prvr != NULL \|\| !strcmp(fbuf, pout)) {
267			sprintf(errmsg,
268			"output file \"%s\" exists",
269			fbuf);
270			error(USER, errmsg);
271			}
272	greg	2.26	continue; /* don't clobber */
273	greg	2.27	}
274	greg	2.8	if (freopen(fbuf, "w", stdout) == NULL) {
275			sprintf(errmsg,
276			"cannot open output file \"%s\"", fbuf);
277			error(SYSTEM, errmsg);
278			}
279	greg	2.17	#ifdef MSDOS
280			setmode(fileno(stdout), O_BINARY);
281			#endif
282	greg	2.8	dupheader();
283			}
284			hres = hresolu; vres = vresolu; pa = pixaspect;
285			if (prvr != NULL)
286			if (viewfile(prvr, &ourview, &rs) <= 0
287			\|\| rs.or != PIXSTANDARD) {
288			sprintf(errmsg,
289			"cannot recover view parameters from \"%s\"", prvr);
290			error(WARNING, errmsg);
291			} else {
292			pa = 0.0;
293			hres = scanlen(&rs);
294			vres = numscans(&rs);
295			}
296	greg	2.9	if ((cp = setview(&ourview)) != NULL)
297			error(USER, cp);
298	greg	2.8	normaspect(viewaspect(&ourview), &pa, &hres, &vres);
299			if (seq) {
300			if (ralrm > 0) {
301	greg	2.11	fprintf(stderr, "FRAME %d:", seq);
302			fprintview(&ourview, stderr);
303			putc('\n', stderr);
304			fflush(stderr);
305	greg	2.8	}
306			printf("FRAME=%d\n", seq);
307			}
308			fputs(VIEWSTR, stdout);
309			fprintview(&ourview, stdout);
310			putchar('\n');
311			if (pa < .99 \|\| pa > 1.01)
312			fputaspect(pa, stdout);
313			fputformat(COLRFMT, stdout);
314			putchar('\n');
315			if (zout != NULL)
316	greg	2.9	sprintf(cp=fbuf, zout, seq);
317	greg	2.8	else
318	greg	2.9	cp = NULL;
319			render(cp, prvr);
320	greg	2.8	prvr = NULL;
321	greg	2.26	npicts++;
322	greg	2.8	} while (seq++);
323	greg	2.26	/* check that we did something */
324			if (npicts == 0)
325			error(WARNING, "no output produced");
326	greg	2.8	}
327
328
329			nextview(fp) /* get next view from fp */
330			FILE *fp;
331			{
332	greg	2.9	char linebuf[256];
333	greg	2.8
334			while (fgets(linebuf, sizeof(linebuf), fp) != NULL)
335	greg	2.9	if (isview(linebuf) && sscanview(&ourview, linebuf) > 0)
336	greg	2.8	return(0);
337			return(EOF);
338			}
339
340
341	greg	1.11	render(zfile, oldfile) /* render the scene */
342			char zfile, oldfile;
343	greg	1.1	{
344	greg	1.16	extern long lseek();
345	greg	1.1	COLOR scanbar[MAXDIV+1]; / scanline arrays of pixel values */
346	greg	1.11	float zbar[MAXDIV+1]; / z values */
347	greg	2.2	char sampdens; / previous sample density */
348	greg	1.1	int ypos; /* current scanline */
349	greg	1.15	int ystep; /* current y step size */
350	greg	1.33	int hstep; /* h step size */
351	greg	1.16	int zfd;
352	greg	1.1	COLOR *colptr;
353	greg	1.11	float *zptr;
354	greg	1.1	register int i;
355	greg	1.9	/* allocate scanlines */
356	greg	1.1	for (i = 0; i <= psample; i++) {
357	greg	2.8	scanbar[i] = (COLOR )malloc(hressizeof(COLOR));
358	greg	1.1	if (scanbar[i] == NULL)
359	greg	1.11	goto memerr;
360	greg	1.1	}
361	greg	2.2	hstep = (psample140+49)/99; / quincunx sampling */
362			ystep = (psample*99+70)/140;
363			if (hstep > 2) {
364	greg	2.8	i = hres/hstep + 2;
365	greg	2.2	if ((sampdens = malloc(i)) == NULL)
366			goto memerr;
367			while (i--)
368			sampdens[i] = hstep;
369			} else
370			sampdens = NULL;
371	greg	2.26	/* open z-file */
372	greg	1.11	if (zfile != NULL) {
373	greg	1.16	if ((zfd = open(zfile, O_WRONLY\|O_CREAT, 0666)) == -1) {
374	greg	2.26	sprintf(errmsg, "cannot open z-file \"%s\"", zfile);
375	greg	1.11	error(SYSTEM, errmsg);
376			}
377	greg	2.17	#ifdef MSDOS
378			setmode(zfd, O_BINARY);
379			#endif
380	greg	1.11	for (i = 0; i <= psample; i++) {
381	greg	2.8	zbar[i] = (float )malloc(hressizeof(float));
382	greg	1.11	if (zbar[i] == NULL)
383			goto memerr;
384			}
385			} else {
386	greg	1.16	zfd = -1;
387	greg	1.11	for (i = 0; i <= psample; i++)
388			zbar[i] = NULL;
389			}
390	greg	1.1	/* write out boundaries */
391	greg	2.8	fprtresolu(hres, vres, stdout);
392	greg	1.10	/* recover file and compute first */
393	greg	1.11	i = salvage(oldfile);
394	greg	2.42	if (i >= vres)
395			goto alldone;
396	greg	1.23	if (zfd != -1 && i > 0 &&
397	greg	2.8	lseek(zfd, (long)ihressizeof(float), 0) == -1)
398	greg	2.26	error(SYSTEM, "z-file seek error in render");
399	greg	2.8	pctdone = 100.0*i/vres;
400	greg	1.24	if (ralrm > 0) /* report init stats */
401			report();
402	greg	2.14	#ifndef BSD
403	greg	1.32	else
404			#endif
405	greg	2.22	signal(SIGCONT, report);
406	greg	2.47	ypos = vres-1 - i; /* initialize sampling */
407	gregl	2.48	if (directvis)
408			init_drawsources(psample);
409	greg	2.8	fillscanline(scanbar[0], zbar[0], sampdens, hres, ypos, hstep);
410	greg	1.10	/* compute scanlines */
411	greg	1.15	for (ypos -= ystep; ypos > -ystep; ypos -= ystep) {
412			/* bottom adjust? */
413			if (ypos < 0) {
414			ystep += ypos;
415			ypos = 0;
416			}
417			colptr = scanbar[ystep]; /* move base to top */
418			scanbar[ystep] = scanbar[0];
419	greg	1.1	scanbar[0] = colptr;
420	greg	1.15	zptr = zbar[ystep];
421			zbar[ystep] = zbar[0];
422	greg	1.11	zbar[0] = zptr;
423	greg	1.10	/* fill base line */
424	greg	2.2	fillscanline(scanbar[0], zbar[0], sampdens,
425	greg	2.8	hres, ypos, hstep);
426	greg	1.10	/* fill bar */
427	greg	2.8	fillscanbar(scanbar, zbar, hres, ypos, ystep);
428	gregl	2.48	if (directvis) /* add bitty sources */
429			drawsources(scanbar, zbar, 0, hres, ypos, ystep);
430	greg	1.10	/* write it out */
431	greg	2.14	#ifndef BSD
432	greg	2.22	signal(SIGCONT, SIG_IGN); /* don't interrupt writes */
433	greg	1.32	#endif
434	greg	1.15	for (i = ystep; i > 0; i--) {
435	greg	1.17	if (zfd != -1 && write(zfd, (char *)zbar[i],
436	greg	2.8	hres*sizeof(float))
437			< hres*sizeof(float))
438	greg	1.1	goto writerr;
439	greg	2.8	if (fwritescan(scanbar[i], hres, stdout) < 0)
440	greg	1.11	goto writerr;
441			}
442	greg	1.1	if (fflush(stdout) == EOF)
443			goto writerr;
444	greg	1.24	/* record progress */
445	greg	2.8	pctdone = 100.0*(vres-1-ypos)/vres;
446	greg	2.32	if (ralrm > 0 && time((time_t *)NULL) >= tlastrept+ralrm)
447	greg	1.24	report();
448	greg	2.14	#ifndef BSD
449	greg	1.32	else
450	greg	2.22	signal(SIGCONT, report);
451	greg	1.32	#endif
452	greg	1.1	}
453	greg	1.11	/* clean up */
454	greg	2.22	signal(SIGCONT, SIG_IGN);
455	greg	2.42	if (zfd != -1 && write(zfd, (char )zbar[0], hressizeof(float))
456			< hres*sizeof(float))
457			goto writerr;
458			fwritescan(scanbar[0], hres, stdout);
459			if (fflush(stdout) == EOF)
460			goto writerr;
461			alldone:
462	greg	1.16	if (zfd != -1) {
463	greg	1.20	if (close(zfd) == -1)
464			goto writerr;
465	greg	1.11	for (i = 0; i <= psample; i++)
466			free((char *)zbar[i]);
467			}
468	greg	1.1	for (i = 0; i <= psample; i++)
469			free((char *)scanbar[i]);
470	greg	2.2	if (sampdens != NULL)
471			free(sampdens);
472	greg	1.11	pctdone = 100.0;
473	greg	2.13	if (ralrm > 0)
474			report();
475	greg	2.23	signal(SIGCONT, SIG_DFL);
476	greg	1.1	return;
477			writerr:
478			error(SYSTEM, "write error in render");
479	greg	1.11	memerr:
480			error(SYSTEM, "out of memory in render");
481	greg	1.1	}
482
483
484	greg	2.2	fillscanline(scanline, zline, sd, xres, y, xstep) /* fill scan at y */
485	greg	2.14	register COLOR *scanline;
486			register float *zline;
487	greg	2.2	register char *sd;
488	greg	1.9	int xres, y, xstep;
489	greg	1.1	{
490	greg	1.33	static int nc = 0; /* number of calls */
491	greg	2.2	int bl = xstep, b = xstep;
492	greg	2.14	double z;
493	greg	1.1	register int i;
494	greg	2.45
495	greg	1.11	z = pixvalue(scanline[0], 0, y);
496			if (zline) zline[0] = z;
497	greg	1.33	/* zig-zag start for quincunx pattern */
498	greg	2.2	for (i = ++nc & 1 ? xstep : xstep/2; i < xres-1+xstep; i += xstep) {
499	greg	1.15	if (i >= xres) {
500			xstep += xres-1-i;
501			i = xres-1;
502			}
503	greg	1.11	z = pixvalue(scanline[i], i, y);
504			if (zline) zline[i] = z;
505	greg	2.2	if (sd) b = sd[0] > sd[1] ? sd[0] : sd[1];
506	greg	2.3	if (i <= xstep)
507			b = fillsample(scanline, zline, 0, y, i, 0, b/2);
508			else
509			b = fillsample(scanline+i-xstep,
510	greg	2.38	zline ? zline+i-xstep : (float *)NULL,
511	greg	2.3	i-xstep, y, xstep, 0, b/2);
512	greg	2.2	if (sd) *sd++ = nc & 1 ? bl : b;
513			bl = b;
514	greg	1.1	}
515	greg	2.2	if (sd && nc & 1) *sd = bl;
516	greg	1.1	}
517
518
519	greg	1.11	fillscanbar(scanbar, zbar, xres, y, ysize) /* fill interior */
520	greg	2.14	register COLOR *scanbar[];
521			register float *zbar[];
522	greg	1.9	int xres, y, ysize;
523	greg	1.1	{
524			COLOR vline[MAXDIV+1];
525	greg	1.11	float zline[MAXDIV+1];
526	greg	1.1	int b = ysize;
527			register int i, j;
528	greg	2.45
529	greg	1.8	for (i = 0; i < xres; i++) {
530	greg	1.1	copycolor(vline[0], scanbar[0][i]);
531			copycolor(vline[ysize], scanbar[ysize][i]);
532	greg	1.11	if (zbar[0]) {
533			zline[0] = zbar[0][i];
534			zline[ysize] = zbar[ysize][i];
535			}
536	greg	2.38	b = fillsample(vline, zbar[0] ? zline : (float *)NULL,
537	greg	1.11	i, y, 0, ysize, b/2);
538	greg	2.45
539	greg	1.1	for (j = 1; j < ysize; j++)
540			copycolor(scanbar[j][i], vline[j]);
541	greg	1.11	if (zbar[0])
542			for (j = 1; j < ysize; j++)
543			zbar[j][i] = zline[j];
544	greg	1.1	}
545			}
546
547
548			int
549	greg	2.14	fillsample(colline, zline, x, y, xlen, ylen, b) /* fill interior points */
550			register COLOR *colline;
551			register float *zline;
552	greg	1.1	int x, y;
553			int xlen, ylen;
554			int b;
555			{
556	greg	2.14	double ratio;
557			double z;
558	greg	1.1	COLOR ctmp;
559			int ncut;
560			register int len;
561	greg	2.45
562	greg	1.1	if (xlen > 0) /* x or y length is zero */
563			len = xlen;
564			else
565			len = ylen;
566	greg	2.45
567	greg	1.1	if (len <= 1) /* limit recursion */
568			return(0);
569	greg	2.45
570			if (b > 0 \|\|
571			(zline && 2.fabs(zline[0]-zline[len]) > maxdiff(zline[0]+zline[len]))
572	greg	1.11	\|\| bigdiff(colline[0], colline[len], maxdiff)) {
573	greg	2.45
574	greg	1.11	z = pixvalue(colline[len>>1], x + (xlen>>1), y + (ylen>>1));
575			if (zline) zline[len>>1] = z;
576	greg	1.1	ncut = 1;
577			} else { /* interpolate */
578			copycolor(colline[len>>1], colline[len]);
579			ratio = (double)(len>>1) / len;
580			scalecolor(colline[len>>1], ratio);
581	greg	1.11	if (zline) zline[len>>1] = zline[len] * ratio;
582			ratio = 1.0 - ratio;
583	greg	1.1	copycolor(ctmp, colline[0]);
584			scalecolor(ctmp, ratio);
585			addcolor(colline[len>>1], ctmp);
586	greg	1.11	if (zline) zline[len>>1] += zline[0] * ratio;
587	greg	1.1	ncut = 0;
588			}
589			/* recurse */
590	greg	1.11	ncut += fillsample(colline, zline, x, y, xlen>>1, ylen>>1, (b-1)/2);
591	greg	2.45
592	greg	2.38	ncut += fillsample(colline+(len>>1),
593			zline ? zline+(len>>1) : (float *)NULL,
594	greg	1.11	x+(xlen>>1), y+(ylen>>1),
595			xlen-(xlen>>1), ylen-(ylen>>1), b/2);
596	greg	1.1
597			return(ncut);
598			}
599
600
601	greg	1.11	double
602	greg	1.1	pixvalue(col, x, y) /* compute pixel value */
603			COLOR col; /* returned color */
604			int x, y; /* pixel position */
605			{
606	greg	1.25	static RAY thisray;
607	greg	1.1
608	greg	2.39	if ((thisray.rmax = viewray(thisray.rorg, thisray.rdir, &ourview,
609			(x+pixjitter())/hres, (y+pixjitter())/vres)) < -FTINY) {
610	greg	1.22	setcolor(col, 0.0, 0.0, 0.0);
611			return(0.0);
612			}
613	greg	1.1
614			rayorigin(&thisray, NULL, PRIMARY, 1.0);
615	greg	1.25
616	greg	2.8	samplendx = pixnumber(x,y,hres,vres); /* set pixel index */
617	greg	1.25
618	greg	1.1	rayvalue(&thisray); /* trace ray */
619
620			copycolor(col, thisray.rcol); /* return color */
621	greg	2.45
622	greg	1.20	return(thisray.rt); /* return distance */
623	greg	1.1	}
624
625
626			int
627			salvage(oldfile) /* salvage scanlines from killed program */
628			char *oldfile;
629			{
630			COLR *scanline;
631			FILE *fp;
632			int x, y;
633
634			if (oldfile == NULL)
635	greg	2.37	goto gotzip;
636
637	greg	1.9	if ((fp = fopen(oldfile, "r")) == NULL) {
638	greg	1.1	sprintf(errmsg, "cannot open recover file \"%s\"", oldfile);
639			error(WARNING, errmsg);
640	greg	2.37	goto gotzip;
641	greg	1.1	}
642	greg	2.17	#ifdef MSDOS
643			setmode(fileno(fp), O_BINARY);
644			#endif
645	greg	1.1	/* discard header */
646	greg	2.19	getheader(fp, NULL, NULL);
647	greg	1.1	/* get picture size */
648	greg	1.36	if (!fscnresolu(&x, &y, fp)) {
649	greg	2.29	sprintf(errmsg, "bad recover file \"%s\" - not removed",
650			oldfile);
651	greg	1.2	error(WARNING, errmsg);
652	greg	1.1	fclose(fp);
653	greg	2.37	goto gotzip;
654	greg	1.1	}
655
656	greg	2.8	if (x != hres \|\| y != vres) {
657	greg	1.1	sprintf(errmsg, "resolution mismatch in recover file \"%s\"",
658			oldfile);
659			error(USER, errmsg);
660			}
661
662	greg	2.8	scanline = (COLR )malloc(hressizeof(COLR));
663	greg	1.1	if (scanline == NULL)
664			error(SYSTEM, "out of memory in salvage");
665	greg	2.8	for (y = 0; y < vres; y++) {
666			if (freadcolrs(scanline, hres, fp) < 0)
667	greg	1.1	break;
668	greg	2.8	if (fwritecolrs(scanline, hres, stdout) < 0)
669	greg	1.1	goto writerr;
670			}
671			if (fflush(stdout) == EOF)
672			goto writerr;
673			free((char *)scanline);
674			fclose(fp);
675			unlink(oldfile);
676			return(y);
677	greg	2.37	gotzip:
678			if (fflush(stdout) == EOF)
679			error(SYSTEM, "error writing picture header");
680			return(0);
681	greg	1.1	writerr:
682	greg	2.9	sprintf(errmsg, "write error during recovery of \"%s\"", oldfile);
683			error(SYSTEM, errmsg);
684	greg	1.31	}
685
686
687			int
688			pixnumber(x, y, xres, yres) /* compute pixel index (brushed) */
689			register int x, y;
690			int xres, yres;
691			{
692			x -= y;
693			while (x < 0)
694			x += xres;
695			return((((x>>2)*yres + y) << 2) + (x & 3));
696	greg	1.1	}