src/rt/rpict.c

/* Copyright (c) 1992 Regents of the University of California */

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

/*
 *  rpict.c - routines and variables for picture generation.
 *
 *     8/14/85
 */

#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  <sys/utsname.h>
#include  <limits.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. */

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

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

COLOR  ambval = BLKCOLOR;               /* 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()))

static 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 */
{
        double  u, s;
#ifdef BSD
        char  hostname[257];
        struct rusage  rubuf;
#else
        struct tms  tbuf;
        struct utsname  nambuf;
#define hostname  nambuf.sysname
#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;
        gethostname(hostname, sizeof(hostname));
#else
        times(&tbuf);
        u = ( tbuf.tms_utime + tbuf.tms_cutime ) / CLK_TCK;
        s = ( tbuf.tms_stime + tbuf.tms_cstime ) / CLK_TCK;
        uname(&nambuf);
#endif

        sprintf(errmsg,
                "%lu rays, %4.2f%% after %.3fu %.3fs %.3fr hours on %s\n",
                        nrays, pctdone, u/3600., s/3600.,
                        (tlastrept-tstart)/3600., hostname);
        eputs(errmsg);
#undef hostname
}
#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);
        signal(SIGCONT, report);
}
#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 (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;
        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);
                                                        /* 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) {
                if (write(zfd, (char *)zbar[0], hres*sizeof(float))
                                < hres*sizeof(float))
                        goto writerr;
                if (close(zfd) == -1)
                        goto writerr;
                for (i = 0; i <= psample; i++)
                        free((char *)zbar[i]);
        }
        fwritescan(scanbar[0], hres, stdout);
        if (fflush(stdout) == EOF)
                goto writerr;
        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 : 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 : 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) : 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 (viewray(thisray.rorg, thisray.rdir, &ourview,
                        (x+pixjitter())/hres, (y+pixjitter())/vres) < 0) {
                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)
                return(0);
        
        if ((fp = fopen(oldfile, "r")) == NULL) {
                sprintf(errmsg, "cannot open recover file \"%s\"", oldfile);
                error(WARNING, errmsg);
                return(0);
        }
#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);
                return(0);
        }

        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);
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:	2.32
Committed:	Mon Nov 22 09:34:15 1993 UTC (30 years, 5 months ago) by greg
Content type:	text/plain
Branch:	MAIN
Changes since 2.31:	+16 -11 lines
Log Message:	compatibility fixes
#	User	Rev	Content
1	greg	2.8	/* Copyright (c) 1992 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			* 8/14/85
11			*/
12
13			#include "ray.h"
14
15	greg	2.32	#include <sys/types.h>
16
17	greg	2.30	#ifndef NIX
18	greg	1.1	#ifdef BSD
19			#include <sys/time.h>
20			#include <sys/resource.h>
21	greg	2.30	#else
22			#include <sys/times.h>
23	greg	2.32	#include <sys/utsname.h>
24	greg	2.30	#include <limits.h>
25	greg	1.34	#endif
26	greg	2.30	#endif
27	greg	1.34
28	greg	2.32	extern time_t time();
29
30	greg	1.14	#include <signal.h>
31	greg	1.1
32			#include "view.h"
33
34	greg	1.36	#include "resolu.h"
35
36	greg	1.1	#include "random.h"
37
38	greg	2.12	#include "paths.h"
39
40	greg	2.21	#define RFTEMPLATE "rfXXXXXX"
41
42	greg	2.22	#ifndef SIGCONT
43			#define SIGCONT SIGIO
44			#endif
45
46	greg	1.25	int dimlist[MAXDIM]; /* sampling dimensions */
47			int ndims = 0; /* number of sampling dimensions */
48			int samplendx; /* sample index number */
49
50	greg	1.12	VIEW ourview = STDVIEW; /* view parameters */
51			int hresolu = 512; /* horizontal resolution */
52			int vresolu = 512; /* vertical resolution */
53	greg	2.14	double pixaspect = 1.0; /* pixel aspect ratio */
54	greg	1.1
55			int psample = 4; /* pixel sample size */
56	greg	2.14	double maxdiff = .05; /* max. difference for interpolation */
57			double dstrpix = 0.67; /* square pixel distribution */
58	greg	1.1
59	greg	2.14	double dstrsrc = 0.0; /* square source distribution */
60			double shadthresh = .05; /* shadow threshold */
61			double shadcert = .5; /* shadow certainty */
62	greg	1.35	int directrelay = 1; /* number of source relays */
63	greg	1.29	int vspretest = 512; /* virtual source pretest density */
64	greg	2.20	int directvis = 1; /* sources visible? */
65	greg	2.14	double srcsizerat = .25; /* maximum ratio source size/dist. */
66	greg	1.1
67	greg	2.14	double specthresh = .15; /* specular sampling threshold */
68			double specjitter = 1.; /* specular sampling jitter */
69	greg	2.5
70	greg	1.1	int maxdepth = 6; /* maximum recursion depth */
71	greg	2.14	double minweight = 5e-3; /* minimum ray weight */
72	greg	1.1
73			COLOR ambval = BLKCOLOR; /* ambient value */
74	greg	2.14	double ambacc = 0.2; /* ambient accuracy */
75	greg	1.6	int ambres = 32; /* ambient resolution */
76	greg	1.1	int ambdiv = 128; /* ambient divisions */
77			int ambssamp = 0; /* ambient super-samples */
78			int ambounce = 0; /* ambient bounces */
79			char amblist[128]; / ambient include/exclude list */
80			int ambincl = -1; /* include == 1, exclude == 0 */
81
82	greg	2.16	#ifdef MSDOS
83			int ralrm = 60; /* seconds between reports */
84			#else
85	greg	1.1	int ralrm = 0; /* seconds between reports */
86	greg	2.16	#endif
87	greg	1.1
88	greg	2.14	double pctdone = 0.0; /* percentage done */
89	greg	1.1
90	greg	2.32	time_t tlastrept = 0L; /* time at last report */
91	greg	1.24
92	greg	2.32	extern time_t tstart; /* starting time */
93	greg	1.24
94	greg	2.24	extern unsigned long nrays; /* number of rays traced */
95	greg	1.1
96	greg	2.14	#define MAXDIV 16 /* maximum sample size */
97	greg	1.1
98	greg	2.14	#define pixjitter() (.5+dstrpix*(.5-frandom()))
99	greg	1.1
100	greg	2.8	static int hres, vres; /* resolution for this frame */
101
102			extern char *mktemp();
103
104	greg	2.14	double pixvalue();
105	greg	1.1
106	greg	2.27	#ifdef NIX
107			#define file_exists(f) (access(f,F_OK)==0)
108			#else
109			#include <sys/types.h>
110			#include <sys/stat.h>
111			int
112			file_exists(fname) /* ordinary file exists? */
113			char *fname;
114			{
115			struct stat sbuf;
116			if (stat(fname, &sbuf) < 0) return(0);
117			return((sbuf.st_mode & S_IFREG) != 0);
118			}
119			#endif
120	greg	1.11
121	greg	2.27
122	greg	1.1	quit(code) /* quit program */
123			int code;
124			{
125	greg	2.8	if (code) /* report status */
126	greg	1.1	report();
127	greg	2.21	headclean(); /* delete header file */
128			pfclean(); /* clean up persist files */
129	greg	1.1	exit(code);
130			}
131
132
133	greg	2.30	#ifndef NIX
134	greg	1.1	report() /* report progress */
135			{
136	greg	2.30	double u, s;
137			#ifdef BSD
138	greg	2.32	char hostname[257];
139	greg	1.1	struct rusage rubuf;
140	greg	2.30	#else
141			struct tms tbuf;
142	greg	2.32	struct utsname nambuf;
143			#define hostname nambuf.sysname
144	greg	2.30	#endif
145	greg	1.1
146	greg	2.32	tlastrept = time((time_t *)NULL);
147	greg	2.30	#ifdef BSD
148	greg	1.1	getrusage(RUSAGE_SELF, &rubuf);
149	greg	2.30	u = rubuf.ru_utime.tv_sec + rubuf.ru_utime.tv_usec/1e6;
150			s = rubuf.ru_stime.tv_sec + rubuf.ru_stime.tv_usec/1e6;
151	greg	1.1	getrusage(RUSAGE_CHILDREN, &rubuf);
152	greg	2.30	u += rubuf.ru_utime.tv_sec + rubuf.ru_utime.tv_usec/1e6;
153			s += rubuf.ru_stime.tv_sec + rubuf.ru_stime.tv_usec/1e6;
154	greg	2.32	gethostname(hostname, sizeof(hostname));
155	greg	2.30	#else
156			times(&tbuf);
157			u = ( tbuf.tms_utime + tbuf.tms_cutime ) / CLK_TCK;
158			s = ( tbuf.tms_stime + tbuf.tms_cstime ) / CLK_TCK;
159	greg	2.32	uname(&nambuf);
160	greg	2.30	#endif
161	greg	1.1
162	greg	2.30	sprintf(errmsg,
163			"%lu rays, %4.2f%% after %.3fu %.3fs %.3fr hours on %s\n",
164			nrays, pctdone, u/3600., s/3600.,
165			(tlastrept-tstart)/3600., hostname);
166	greg	1.24	eputs(errmsg);
167	greg	2.32	#undef hostname
168	greg	1.24	}
169	greg	1.1	#else
170	greg	1.24	report() /* report progress */
171			{
172	greg	2.32	tlastrept = time((time_t *)NULL);
173	greg	2.30	sprintf(errmsg, "%lu rays, %4.2f%% after %5.4f hours\n",
174	greg	1.24	nrays, pctdone, (tlastrept-tstart)/3600.0);
175	greg	1.1	eputs(errmsg);
176	greg	2.22	signal(SIGCONT, report);
177	greg	1.1	}
178	greg	1.24	#endif
179	greg	1.1
180
181	greg	2.8	rpict(seq, pout, zout, prvr) /* generate image(s) */
182			int seq;
183			char pout, zout, *prvr;
184			/*
185			* If seq is greater than zero, then we will render a sequence of
186			* images based on view parameter strings read from the standard input.
187			* If pout is NULL, then all images will be sent to the standard ouput.
188			* If seq is greater than zero and prvr is an integer, then it is the
189			* frame number at which rendering should begin. Preceeding view parameter
190			* strings will be skipped in the input.
191			* If pout and prvr are the same, prvr is renamed to avoid overwriting.
192			* Note that pout and zout should contain %d format specifications for
193			* sequenced file naming.
194			*/
195			{
196	greg	2.21	extern char rindex(), strncpy(), strcat(), strcpy();
197	greg	2.9	char fbuf[128], fbuf2[128];
198	greg	2.26	int npicts;
199	greg	2.9	register char *cp;
200	greg	2.14	RESOLU rs;
201			double pa;
202	greg	2.8	/* check sampling */
203			if (psample < 1)
204			psample = 1;
205			else if (psample > MAXDIV) {
206			sprintf(errmsg, "pixel sampling reduced from %d to %d",
207			psample, MAXDIV);
208			error(WARNING, errmsg);
209			psample = MAXDIV;
210			}
211			/* get starting frame */
212			if (seq <= 0)
213			seq = 0;
214			else if (prvr != NULL && isint(prvr)) {
215	greg	2.9	register int rn; /* skip to specified view */
216	greg	2.8	if ((rn = atoi(prvr)) < seq)
217			error(USER, "recover frame less than start frame");
218			if (pout == NULL)
219			error(USER, "missing output file specification");
220			for ( ; seq < rn; seq++)
221			if (nextview(stdin) == EOF)
222			error(USER, "unexpected EOF on view input");
223			prvr = fbuf; /* mark for renaming */
224			}
225	greg	2.18	if (pout != NULL & prvr != NULL) {
226	greg	2.8	sprintf(fbuf, pout, seq);
227	greg	2.18	if (!strcmp(prvr, fbuf)) { /* rename */
228			strcpy(fbuf2, fbuf);
229			for (cp = fbuf2; *cp; cp++)
230			;
231			while (cp > fbuf2 && !ISDIRSEP(cp[-1]))
232			cp--;
233			strcpy(cp, RFTEMPLATE);
234	greg	2.8	prvr = mktemp(fbuf2);
235	greg	2.28	if (rename(fbuf, prvr) < 0)
236			if (errno == ENOENT) { /* ghost file */
237			sprintf(errmsg,
238			"new output file \"%s\"",
239			fbuf);
240			error(WARNING, errmsg);
241			prvr = NULL;
242			} else { /* serious error */
243			sprintf(errmsg,
244	greg	2.8	"cannot rename \"%s\" to \"%s\"",
245			fbuf, prvr);
246	greg	2.28	error(SYSTEM, errmsg);
247			}
248	greg	2.8	}
249			}
250	greg	2.26	npicts = 0; /* render sequence */
251	greg	2.8	do {
252			if (seq && nextview(stdin) == EOF)
253			break;
254	greg	2.25	pctdone = 0.0;
255	greg	2.8	if (pout != NULL) {
256			sprintf(fbuf, pout, seq);
257	greg	2.27	if (file_exists(fbuf)) {
258			if (prvr != NULL \|\| !strcmp(fbuf, pout)) {
259			sprintf(errmsg,
260			"output file \"%s\" exists",
261			fbuf);
262			error(USER, errmsg);
263			}
264	greg	2.26	continue; /* don't clobber */
265	greg	2.27	}
266	greg	2.8	if (freopen(fbuf, "w", stdout) == NULL) {
267			sprintf(errmsg,
268			"cannot open output file \"%s\"", fbuf);
269			error(SYSTEM, errmsg);
270			}
271	greg	2.17	#ifdef MSDOS
272			setmode(fileno(stdout), O_BINARY);
273			#endif
274	greg	2.8	dupheader();
275			}
276			hres = hresolu; vres = vresolu; pa = pixaspect;
277			if (prvr != NULL)
278			if (viewfile(prvr, &ourview, &rs) <= 0
279			\|\| rs.or != PIXSTANDARD) {
280			sprintf(errmsg,
281			"cannot recover view parameters from \"%s\"", prvr);
282			error(WARNING, errmsg);
283			} else {
284			pa = 0.0;
285			hres = scanlen(&rs);
286			vres = numscans(&rs);
287			}
288	greg	2.9	if ((cp = setview(&ourview)) != NULL)
289			error(USER, cp);
290	greg	2.8	normaspect(viewaspect(&ourview), &pa, &hres, &vres);
291			if (seq) {
292			if (ralrm > 0) {
293	greg	2.11	fprintf(stderr, "FRAME %d:", seq);
294			fprintview(&ourview, stderr);
295			putc('\n', stderr);
296			fflush(stderr);
297	greg	2.8	}
298			printf("FRAME=%d\n", seq);
299			}
300			fputs(VIEWSTR, stdout);
301			fprintview(&ourview, stdout);
302			putchar('\n');
303			if (pa < .99 \|\| pa > 1.01)
304			fputaspect(pa, stdout);
305			fputformat(COLRFMT, stdout);
306			putchar('\n');
307			if (zout != NULL)
308	greg	2.9	sprintf(cp=fbuf, zout, seq);
309	greg	2.8	else
310	greg	2.9	cp = NULL;
311			render(cp, prvr);
312	greg	2.8	prvr = NULL;
313	greg	2.26	npicts++;
314	greg	2.8	} while (seq++);
315	greg	2.26	/* check that we did something */
316			if (npicts == 0)
317			error(WARNING, "no output produced");
318	greg	2.8	}
319
320
321			nextview(fp) /* get next view from fp */
322			FILE *fp;
323			{
324	greg	2.9	char linebuf[256];
325	greg	2.8
326			while (fgets(linebuf, sizeof(linebuf), fp) != NULL)
327	greg	2.9	if (isview(linebuf) && sscanview(&ourview, linebuf) > 0)
328	greg	2.8	return(0);
329			return(EOF);
330			}
331
332
333	greg	1.11	render(zfile, oldfile) /* render the scene */
334			char zfile, oldfile;
335	greg	1.1	{
336	greg	1.16	extern long lseek();
337	greg	1.1	COLOR scanbar[MAXDIV+1]; / scanline arrays of pixel values */
338	greg	1.11	float zbar[MAXDIV+1]; / z values */
339	greg	2.2	char sampdens; / previous sample density */
340	greg	1.1	int ypos; /* current scanline */
341	greg	1.15	int ystep; /* current y step size */
342	greg	1.33	int hstep; /* h step size */
343	greg	1.16	int zfd;
344	greg	1.1	COLOR *colptr;
345	greg	1.11	float *zptr;
346	greg	1.1	register int i;
347	greg	1.9	/* allocate scanlines */
348	greg	1.1	for (i = 0; i <= psample; i++) {
349	greg	2.8	scanbar[i] = (COLOR )malloc(hressizeof(COLOR));
350	greg	1.1	if (scanbar[i] == NULL)
351	greg	1.11	goto memerr;
352	greg	1.1	}
353	greg	2.2	hstep = (psample140+49)/99; / quincunx sampling */
354			ystep = (psample*99+70)/140;
355			if (hstep > 2) {
356	greg	2.8	i = hres/hstep + 2;
357	greg	2.2	if ((sampdens = malloc(i)) == NULL)
358			goto memerr;
359			while (i--)
360			sampdens[i] = hstep;
361			} else
362			sampdens = NULL;
363	greg	2.26	/* open z-file */
364	greg	1.11	if (zfile != NULL) {
365	greg	1.16	if ((zfd = open(zfile, O_WRONLY\|O_CREAT, 0666)) == -1) {
366	greg	2.26	sprintf(errmsg, "cannot open z-file \"%s\"", zfile);
367	greg	1.11	error(SYSTEM, errmsg);
368			}
369	greg	2.17	#ifdef MSDOS
370			setmode(zfd, O_BINARY);
371			#endif
372	greg	1.11	for (i = 0; i <= psample; i++) {
373	greg	2.8	zbar[i] = (float )malloc(hressizeof(float));
374	greg	1.11	if (zbar[i] == NULL)
375			goto memerr;
376			}
377			} else {
378	greg	1.16	zfd = -1;
379	greg	1.11	for (i = 0; i <= psample; i++)
380			zbar[i] = NULL;
381			}
382	greg	1.1	/* write out boundaries */
383	greg	2.8	fprtresolu(hres, vres, stdout);
384	greg	1.10	/* recover file and compute first */
385	greg	1.11	i = salvage(oldfile);
386	greg	1.23	if (zfd != -1 && i > 0 &&
387	greg	2.8	lseek(zfd, (long)ihressizeof(float), 0) == -1)
388	greg	2.26	error(SYSTEM, "z-file seek error in render");
389	greg	2.8	pctdone = 100.0*i/vres;
390	greg	1.24	if (ralrm > 0) /* report init stats */
391			report();
392	greg	2.14	#ifndef BSD
393	greg	1.32	else
394			#endif
395	greg	2.22	signal(SIGCONT, report);
396	greg	2.8	ypos = vres-1 - i;
397			fillscanline(scanbar[0], zbar[0], sampdens, hres, ypos, hstep);
398	greg	1.10	/* compute scanlines */
399	greg	1.15	for (ypos -= ystep; ypos > -ystep; ypos -= ystep) {
400			/* bottom adjust? */
401			if (ypos < 0) {
402			ystep += ypos;
403			ypos = 0;
404			}
405			colptr = scanbar[ystep]; /* move base to top */
406			scanbar[ystep] = scanbar[0];
407	greg	1.1	scanbar[0] = colptr;
408	greg	1.15	zptr = zbar[ystep];
409			zbar[ystep] = zbar[0];
410	greg	1.11	zbar[0] = zptr;
411	greg	1.10	/* fill base line */
412	greg	2.2	fillscanline(scanbar[0], zbar[0], sampdens,
413	greg	2.8	hres, ypos, hstep);
414	greg	1.10	/* fill bar */
415	greg	2.8	fillscanbar(scanbar, zbar, hres, ypos, ystep);
416	greg	1.10	/* write it out */
417	greg	2.14	#ifndef BSD
418	greg	2.22	signal(SIGCONT, SIG_IGN); /* don't interrupt writes */
419	greg	1.32	#endif
420	greg	1.15	for (i = ystep; i > 0; i--) {
421	greg	1.17	if (zfd != -1 && write(zfd, (char *)zbar[i],
422	greg	2.8	hres*sizeof(float))
423			< hres*sizeof(float))
424	greg	1.1	goto writerr;
425	greg	2.8	if (fwritescan(scanbar[i], hres, stdout) < 0)
426	greg	1.11	goto writerr;
427			}
428	greg	1.1	if (fflush(stdout) == EOF)
429			goto writerr;
430	greg	1.24	/* record progress */
431	greg	2.8	pctdone = 100.0*(vres-1-ypos)/vres;
432	greg	2.32	if (ralrm > 0 && time((time_t *)NULL) >= tlastrept+ralrm)
433	greg	1.24	report();
434	greg	2.14	#ifndef BSD
435	greg	1.32	else
436	greg	2.22	signal(SIGCONT, report);
437	greg	1.32	#endif
438	greg	1.1	}
439	greg	1.11	/* clean up */
440	greg	2.22	signal(SIGCONT, SIG_IGN);
441	greg	1.16	if (zfd != -1) {
442	greg	2.8	if (write(zfd, (char )zbar[0], hressizeof(float))
443			< hres*sizeof(float))
444	greg	1.11	goto writerr;
445	greg	1.20	if (close(zfd) == -1)
446			goto writerr;
447	greg	1.11	for (i = 0; i <= psample; i++)
448			free((char *)zbar[i]);
449			}
450	greg	2.8	fwritescan(scanbar[0], hres, stdout);
451	greg	1.10	if (fflush(stdout) == EOF)
452			goto writerr;
453	greg	1.1	for (i = 0; i <= psample; i++)
454			free((char *)scanbar[i]);
455	greg	2.2	if (sampdens != NULL)
456			free(sampdens);
457	greg	1.11	pctdone = 100.0;
458	greg	2.13	if (ralrm > 0)
459			report();
460	greg	2.23	signal(SIGCONT, SIG_DFL);
461	greg	1.1	return;
462			writerr:
463			error(SYSTEM, "write error in render");
464	greg	1.11	memerr:
465			error(SYSTEM, "out of memory in render");
466	greg	1.1	}
467
468
469	greg	2.2	fillscanline(scanline, zline, sd, xres, y, xstep) /* fill scan at y */
470	greg	2.14	register COLOR *scanline;
471			register float *zline;
472	greg	2.2	register char *sd;
473	greg	1.9	int xres, y, xstep;
474	greg	1.1	{
475	greg	1.33	static int nc = 0; /* number of calls */
476	greg	2.2	int bl = xstep, b = xstep;
477	greg	2.14	double z;
478	greg	1.1	register int i;
479
480	greg	1.11	z = pixvalue(scanline[0], 0, y);
481			if (zline) zline[0] = z;
482	greg	1.33	/* zig-zag start for quincunx pattern */
483	greg	2.2	for (i = ++nc & 1 ? xstep : xstep/2; i < xres-1+xstep; i += xstep) {
484	greg	1.15	if (i >= xres) {
485			xstep += xres-1-i;
486			i = xres-1;
487			}
488	greg	1.11	z = pixvalue(scanline[i], i, y);
489			if (zline) zline[i] = z;
490	greg	2.2	if (sd) b = sd[0] > sd[1] ? sd[0] : sd[1];
491	greg	2.3	if (i <= xstep)
492			b = fillsample(scanline, zline, 0, y, i, 0, b/2);
493			else
494			b = fillsample(scanline+i-xstep,
495			zline ? zline+i-xstep : NULL,
496			i-xstep, y, xstep, 0, b/2);
497	greg	2.2	if (sd) *sd++ = nc & 1 ? bl : b;
498			bl = b;
499	greg	1.1	}
500	greg	2.2	if (sd && nc & 1) *sd = bl;
501	greg	1.1	}
502
503
504	greg	1.11	fillscanbar(scanbar, zbar, xres, y, ysize) /* fill interior */
505	greg	2.14	register COLOR *scanbar[];
506			register float *zbar[];
507	greg	1.9	int xres, y, ysize;
508	greg	1.1	{
509			COLOR vline[MAXDIV+1];
510	greg	1.11	float zline[MAXDIV+1];
511	greg	1.1	int b = ysize;
512			register int i, j;
513
514	greg	1.8	for (i = 0; i < xres; i++) {
515	greg	1.1
516			copycolor(vline[0], scanbar[0][i]);
517			copycolor(vline[ysize], scanbar[ysize][i]);
518	greg	1.11	if (zbar[0]) {
519			zline[0] = zbar[0][i];
520			zline[ysize] = zbar[ysize][i];
521			}
522	greg	1.1
523	greg	1.11	b = fillsample(vline, zbar[0] ? zline : NULL,
524			i, y, 0, ysize, b/2);
525	greg	1.1
526			for (j = 1; j < ysize; j++)
527			copycolor(scanbar[j][i], vline[j]);
528	greg	1.11	if (zbar[0])
529			for (j = 1; j < ysize; j++)
530			zbar[j][i] = zline[j];
531	greg	1.1	}
532			}
533
534
535			int
536	greg	2.14	fillsample(colline, zline, x, y, xlen, ylen, b) /* fill interior points */
537			register COLOR *colline;
538			register float *zline;
539	greg	1.1	int x, y;
540			int xlen, ylen;
541			int b;
542			{
543	greg	2.14	double ratio;
544			double z;
545	greg	1.1	COLOR ctmp;
546			int ncut;
547			register int len;
548
549			if (xlen > 0) /* x or y length is zero */
550			len = xlen;
551			else
552			len = ylen;
553
554			if (len <= 1) /* limit recursion */
555			return(0);
556
557	greg	1.11	if (b > 0
558			\|\| (zline && 2.fabs(zline[0]-zline[len]) > maxdiff(zline[0]+zline[len]))
559			\|\| bigdiff(colline[0], colline[len], maxdiff)) {
560	greg	1.1
561	greg	1.11	z = pixvalue(colline[len>>1], x + (xlen>>1), y + (ylen>>1));
562			if (zline) zline[len>>1] = z;
563	greg	1.1	ncut = 1;
564
565			} else { /* interpolate */
566
567			copycolor(colline[len>>1], colline[len]);
568			ratio = (double)(len>>1) / len;
569			scalecolor(colline[len>>1], ratio);
570	greg	1.11	if (zline) zline[len>>1] = zline[len] * ratio;
571			ratio = 1.0 - ratio;
572	greg	1.1	copycolor(ctmp, colline[0]);
573			scalecolor(ctmp, ratio);
574			addcolor(colline[len>>1], ctmp);
575	greg	1.11	if (zline) zline[len>>1] += zline[0] * ratio;
576	greg	1.1	ncut = 0;
577			}
578			/* recurse */
579	greg	1.11	ncut += fillsample(colline, zline, x, y, xlen>>1, ylen>>1, (b-1)/2);
580	greg	1.1
581	greg	1.11	ncut += fillsample(colline+(len>>1), zline ? zline+(len>>1) : NULL,
582			x+(xlen>>1), y+(ylen>>1),
583			xlen-(xlen>>1), ylen-(ylen>>1), b/2);
584	greg	1.1
585			return(ncut);
586			}
587
588
589	greg	1.11	double
590	greg	1.1	pixvalue(col, x, y) /* compute pixel value */
591			COLOR col; /* returned color */
592			int x, y; /* pixel position */
593			{
594	greg	1.25	static RAY thisray;
595	greg	1.1
596	greg	1.22	if (viewray(thisray.rorg, thisray.rdir, &ourview,
597	greg	2.8	(x+pixjitter())/hres, (y+pixjitter())/vres) < 0) {
598	greg	1.22	setcolor(col, 0.0, 0.0, 0.0);
599			return(0.0);
600			}
601	greg	1.1
602			rayorigin(&thisray, NULL, PRIMARY, 1.0);
603	greg	1.25
604	greg	2.8	samplendx = pixnumber(x,y,hres,vres); /* set pixel index */
605	greg	1.25
606	greg	1.1	rayvalue(&thisray); /* trace ray */
607
608			copycolor(col, thisray.rcol); /* return color */
609	greg	1.11
610	greg	1.20	return(thisray.rt); /* return distance */
611	greg	1.1	}
612
613
614			int
615			salvage(oldfile) /* salvage scanlines from killed program */
616			char *oldfile;
617			{
618			COLR *scanline;
619			FILE *fp;
620			int x, y;
621
622			if (oldfile == NULL)
623			return(0);
624	greg	1.9
625			if ((fp = fopen(oldfile, "r")) == NULL) {
626	greg	1.1	sprintf(errmsg, "cannot open recover file \"%s\"", oldfile);
627			error(WARNING, errmsg);
628			return(0);
629			}
630	greg	2.17	#ifdef MSDOS
631			setmode(fileno(fp), O_BINARY);
632			#endif
633	greg	1.1	/* discard header */
634	greg	2.19	getheader(fp, NULL, NULL);
635	greg	1.1	/* get picture size */
636	greg	1.36	if (!fscnresolu(&x, &y, fp)) {
637	greg	2.29	sprintf(errmsg, "bad recover file \"%s\" - not removed",
638			oldfile);
639	greg	1.2	error(WARNING, errmsg);
640	greg	1.1	fclose(fp);
641			return(0);
642			}
643
644	greg	2.8	if (x != hres \|\| y != vres) {
645	greg	1.1	sprintf(errmsg, "resolution mismatch in recover file \"%s\"",
646			oldfile);
647			error(USER, errmsg);
648			}
649
650	greg	2.8	scanline = (COLR )malloc(hressizeof(COLR));
651	greg	1.1	if (scanline == NULL)
652			error(SYSTEM, "out of memory in salvage");
653	greg	2.8	for (y = 0; y < vres; y++) {
654			if (freadcolrs(scanline, hres, fp) < 0)
655	greg	1.1	break;
656	greg	2.8	if (fwritecolrs(scanline, hres, stdout) < 0)
657	greg	1.1	goto writerr;
658			}
659			if (fflush(stdout) == EOF)
660			goto writerr;
661			free((char *)scanline);
662			fclose(fp);
663			unlink(oldfile);
664			return(y);
665			writerr:
666	greg	2.9	sprintf(errmsg, "write error during recovery of \"%s\"", oldfile);
667			error(SYSTEM, errmsg);
668	greg	1.31	}
669
670
671			int
672			pixnumber(x, y, xres, yres) /* compute pixel index (brushed) */
673			register int x, y;
674			int xres, yres;
675			{
676			x -= y;
677			while (x < 0)
678			x += xres;
679			return((((x>>2)*yres + y) << 2) + (x & 3));
680	greg	1.1	}