src/px/pinterp.c

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

/*
 * Interpolate and extrapolate pictures with different view parameters.
 *
 *      Greg Ward       09Dec89
 */

#include "standard.h"

#include <fcntl.h>

#include "view.h"

#include "color.h"

#ifndef BSD
#define vfork           fork
#endif

#define pscan(y)        (ourpict+(y)*hresolu)
#define zscan(y)        (ourzbuf+(y)*hresolu)

#define F_FORE          1               /* fill foreground */
#define F_BACK          2               /* fill background */

#define PACKSIZ         42              /* calculation packet size */

#define RTCOM           "rtrace -h -ovl -fff %s"

#define ABS(x)          ((x)>0?(x):-(x))

struct position {int x,y; float z;};

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

double  zeps = .02;                     /* allowed z epsilon */

COLR    *ourpict;                       /* output picture */
float   *ourzbuf;                       /* corresponding z-buffer */

char    *progname;

int     fillo = F_FORE|F_BACK;          /* selected fill options */
int     fillsamp = 0;                   /* sample separation (0 == inf) */
extern int      backfill(), rcalfill(); /* fill functions */
int     (*fillfunc)() = backfill;       /* selected fill function */
COLR    backcolr = BLKCOLR;             /* background color */
double  backz = 0.0;                    /* background z value */
int     normdist = 1;                   /* normalized distance? */
double  ourexp = -1;                    /* output picture exposure */

VIEW    theirview = STDVIEW;            /* input view */
int     gotview;                        /* got input view? */
int     thresolu, tvresolu;             /* input resolution */
double  theirexp;                       /* input picture exposure */
double  theirs2ours[4][4];              /* transformation matrix */

int     childpid = -1;                  /* id of fill process */
FILE    *psend, *precv;                 /* pipes to/from fill calculation */
int     queue[PACKSIZ][2];              /* pending pixels */
int     queuesiz;                       /* number of pixels pending */


main(argc, argv)                        /* interpolate pictures */
int     argc;
char    *argv[];
{
#define check(olen,narg)        if (argv[i][olen] || narg >= argc-i) goto badopt
        extern double   atof();
        int     gotvfile = 0;
        char    *zfile = NULL;
        char    *err;
        int     i, rval;

        progname = argv[0];

        for (i = 1; i < argc && argv[i][0] == '-'; i++) {
                rval = getviewopt(&ourview, argc-i, argv+i);
                if (rval >= 0) {
                        i += rval;
                        continue;
                }
                switch (argv[i][1]) {
                case 't':                               /* threshold */
                        check(2,1);
                        zeps = atof(argv[++i]);
                        break;
                case 'n':                               /* dist. normalized? */
                        check(2,0);
                        normdist = !normdist;
                        break;
                case 'f':                               /* fill type */
                        switch (argv[i][2]) {
                        case '0':                               /* none */
                                check(3,0);
                                fillo = 0;
                                break;
                        case 'f':                               /* foreground */
                                check(3,0);
                                fillo = F_FORE;
                                break;
                        case 'b':                               /* background */
                                check(3,0);
                                fillo = F_BACK;
                                break;
                        case 'a':                               /* all */
                                check(3,0);
                                fillo = F_FORE|F_BACK;
                                break;
                        case 's':                               /* sample */
                                check(3,1);
                                fillsamp = atoi(argv[++i]);
                                break;
                        case 'c':                               /* color */
                                check(3,3);
                                fillfunc = backfill;
                                setcolr(backcolr, atof(argv[i+1]),
                                        atof(argv[i+2]), atof(argv[i+3]));
                                i += 3;
                                break;
                        case 'z':                               /* z value */
                                check(3,1);
                                fillfunc = backfill;
                                backz = atof(argv[++i]);
                                break;
                        case 'r':                               /* rtrace */
                                check(3,1);
                                fillfunc = rcalfill;
                                calstart(RTCOM, argv[++i]);
                                break;
                        default:
                                goto badopt;
                        }
                        break;
                case 'z':                               /* z file */
                        check(2,1);
                        zfile = argv[++i];
                        break;
                case 'x':                               /* x resolution */
                        check(2,1);
                        hresolu = atoi(argv[++i]);
                        break;
                case 'y':                               /* y resolution */
                        check(2,1);
                        vresolu = atoi(argv[++i]);
                        break;
                case 'p':                               /* pixel aspect */
                        check(2,1);
                        pixaspect = atof(argv[++i]);
                        break;
                case 'v':                               /* view file */
                        if (argv[i][2] != 'f')
                                goto badopt;
                        check(3,1);
                        gotvfile = viewfile(argv[++i], &ourview, 0, 0);
                        if (gotvfile < 0) {
                                perror(argv[i]);
                                exit(1);
                        } else if (gotvfile == 0) {
                                fprintf(stderr, "%s: bad view file\n",
                                                argv[i]);
                                exit(1);
                        }
                        break;
                default:
                badopt:
                        fprintf(stderr, "%s: command line error at '%s'\n",
                                        progname, argv[i]);
                        goto userr;
                }
        }
                                                /* check arguments */
        if ((argc-i)%2)
                goto userr;
                                                /* set view */
        if (err = setview(&ourview)) {
                fprintf(stderr, "%s: %s\n", progname, err);
                exit(1);
        }
        normaspect(viewaspect(&ourview), &pixaspect, &hresolu, &vresolu);
                                                /* allocate frame */
        ourpict = (COLR *)malloc(hresolu*vresolu*sizeof(COLR));
        ourzbuf = (float *)calloc(hresolu*vresolu,sizeof(float));
        if (ourpict == NULL || ourzbuf == NULL)
                syserror();
                                                        /* get input */
        for ( ; i < argc; i += 2)
                addpicture(argv[i], argv[i+1]);
                                                        /* fill in spaces */
        if (fillo&F_BACK)
                backpicture(fillfunc, fillsamp);
        else
                fillpicture(fillfunc);
                                                        /* close calculation */
        caldone();
                                                        /* add to header */
        printargs(argc, argv, stdout);
        if (gotvfile) {
                fputs(VIEWSTR, stdout);
                fprintview(&ourview, stdout);
                putc('\n', stdout);
        }
        if (pixaspect < .99 || pixaspect > 1.01)
                fputaspect(pixaspect, stdout);
        if (ourexp > 0 && (ourexp < .995 || ourexp > 1.005))
                fputexpos(ourexp, stdout);
        putc('\n', stdout);
                                                        /* write picture */
        writepicture();
                                                        /* write z file */
        if (zfile != NULL)
                writedistance(zfile);

        exit(0);
userr:
        fprintf(stderr,
        "Usage: %s [view opts][-t eps][-z zout][-fT][-n] pfile zspec ..\n",
                        progname);
        exit(1);
#undef check
}


headline(s)                             /* process header string */
char    *s;
{
        static char     *altname[] = {VIEWSTR,"rpict","rview","pinterp",NULL};
        register char   **an;

        putc('\t', stdout);
        fputs(s, stdout);

        if (isexpos(s)) {
                theirexp *= exposval(s);
                return;
        }
        for (an = altname; *an != NULL; an++)
                if (!strncmp(*an, s, strlen(*an))) {
                        if (sscanview(&theirview, s+strlen(*an)) > 0)
                                gotview++;
                        break;
                }
}


addpicture(pfile, zspec)                /* add picture to output */
char    *pfile, *zspec;
{
        extern double   atof();
        FILE    *pfp;
        int     zfd;
        char    *err;
        COLR    *scanin;
        float   *zin;
        struct position *plast;
        int     y;
                                        /* open picture file */
        if ((pfp = fopen(pfile, "r")) == NULL) {
                perror(pfile);
                exit(1);
        }
                                        /* get header with exposure and view */
        theirexp = 1.0;
        gotview = 0;
        printf("%s:\n", pfile);
        getheader(pfp, headline);
        if (!gotview || fgetresolu(&thresolu, &tvresolu, pfp)
                        != (YMAJOR|YDECR)) {
                fprintf(stderr, "%s: picture view error\n", pfile);
                exit(1);
        }
        if (ourexp <= 0)
                ourexp = theirexp;
        else if (ABS(theirexp-ourexp) > .01*ourexp)
                fprintf(stderr, "%s: different exposure (warning)\n", pfile);
        if (err = setview(&theirview)) {
                fprintf(stderr, "%s: %s\n", pfile, err);
                exit(1);
        }
                                        /* compute transformation */
        pixform(theirs2ours, &theirview, &ourview);
                                        /* allocate scanlines */
        scanin = (COLR *)malloc(thresolu*sizeof(COLR));
        zin = (float *)malloc(thresolu*sizeof(float));
        plast = (struct position *)calloc(thresolu, sizeof(struct position));
        if (scanin == NULL || zin == NULL || plast == NULL)
                syserror();
                                        /* get z specification or file */
        if ((zfd = open(zspec, O_RDONLY)) == -1) {
                double  zvalue;
                register int    x;
                if (!isfloat(zspec) || (zvalue = atof(zspec)) <= 0.0) {
                        perror(zspec);
                        exit(1);
                }
                for (x = 0; x < thresolu; x++)
                        zin[x] = zvalue;
        }
                                        /* load image */
        for (y = tvresolu-1; y >= 0; y--) {
                if (freadcolrs(scanin, thresolu, pfp) < 0) {
                        fprintf(stderr, "%s: read error\n", pfile);
                        exit(1);
                }
                if (zfd != -1 && read(zfd,(char *)zin,thresolu*sizeof(float))
                                < thresolu*sizeof(float)) {
                        fprintf(stderr, "%s: read error\n", zspec);
                        exit(1);
                }
                addscanline(y, scanin, zin, plast);
        }
                                        /* clean up */
        free((char *)scanin);
        free((char *)zin);
        free((char *)plast);
        fclose(pfp);
        if (zfd != -1)
                close(zfd);
}


pixform(xfmat, vw1, vw2)                /* compute view1 to view2 matrix */
register double xfmat[4][4];
register VIEW   *vw1, *vw2;
{
        double  m4t[4][4];

        setident4(xfmat);
        xfmat[0][0] = vw1->hvec[0];
        xfmat[0][1] = vw1->hvec[1];
        xfmat[0][2] = vw1->hvec[2];
        xfmat[1][0] = vw1->vvec[0];
        xfmat[1][1] = vw1->vvec[1];
        xfmat[1][2] = vw1->vvec[2];
        xfmat[2][0] = vw1->vdir[0];
        xfmat[2][1] = vw1->vdir[1];
        xfmat[2][2] = vw1->vdir[2];
        xfmat[3][0] = vw1->vp[0];
        xfmat[3][1] = vw1->vp[1];
        xfmat[3][2] = vw1->vp[2];
        setident4(m4t);
        m4t[0][0] = vw2->hvec[0]/vw2->hn2;
        m4t[1][0] = vw2->hvec[1]/vw2->hn2;
        m4t[2][0] = vw2->hvec[2]/vw2->hn2;
        m4t[3][0] = -DOT(vw2->vp,vw2->hvec)/vw2->hn2;
        m4t[0][1] = vw2->vvec[0]/vw2->vn2;
        m4t[1][1] = vw2->vvec[1]/vw2->vn2;
        m4t[2][1] = vw2->vvec[2]/vw2->vn2;
        m4t[3][1] = -DOT(vw2->vp,vw2->vvec)/vw2->vn2;
        m4t[0][2] = vw2->vdir[0];
        m4t[1][2] = vw2->vdir[1];
        m4t[2][2] = vw2->vdir[2];
        m4t[3][2] = -DOT(vw2->vp,vw2->vdir);
        multmat4(xfmat, xfmat, m4t);
}


addscanline(y, pline, zline, lasty)     /* add scanline to output */
int     y;
COLR    *pline;
float   *zline;
struct position *lasty;         /* input/output */
{
        extern double   sqrt();
        double  pos[3];
        struct position lastx, newpos;
        register int    x;

        lastx.z = 0;
        for (x = thresolu-1; x >= 0; x--) {
                pos[0] = (x+.5)/thresolu + theirview.hoff - .5;
                pos[1] = (y+.5)/tvresolu + theirview.voff - .5;
                pos[2] = zline[x];
                if (theirview.type == VT_PER) {
                        if (normdist)   /* adjust for eye-ray distance */
                                pos[2] /= sqrt( 1.
                                        + pos[0]*pos[0]*theirview.hn2
                                        + pos[1]*pos[1]*theirview.vn2 );
                        pos[0] *= pos[2];
                        pos[1] *= pos[2];
                }
                multp3(pos, pos, theirs2ours);
                if (pos[2] <= 0) {
                        lasty[x].z = lastx.z = 0;       /* mark invalid */
                        continue;
                }
                if (ourview.type == VT_PER) {
                        pos[0] /= pos[2];
                        pos[1] /= pos[2];
                }
                pos[0] += .5 - ourview.hoff;
                pos[1] += .5 - ourview.voff;
                newpos.x = pos[0] * hresolu;
                newpos.y = pos[1] * vresolu;
                newpos.z = zline[x];
                                        /* add pixel to our image */
                if (pos[0] >= 0 && newpos.x < hresolu
                                && pos[1] >= 0 && newpos.y < vresolu) {
                        addpixel(&newpos, &lastx, &lasty[x], pline[x], pos[2]);
                        lasty[x].x = lastx.x = newpos.x;
                        lasty[x].y = lastx.y = newpos.y;
                        lasty[x].z = lastx.z = newpos.z;
                } else
                        lasty[x].z = lastx.z = 0;       /* mark invalid */
        }
}


addpixel(p0, p1, p2, pix, z)            /* fill in pixel parallelogram */
struct position *p0, *p1, *p2;
COLR    pix;
double  z;
{
        double  zt = 2.*zeps*p0->z;             /* threshold */
        int     s1x, s1y, s2x, s2y;             /* step sizes */
        int     l1, l2, c1, c2;                 /* side lengths and counters */
        int     p1isy;                          /* p0p1 along y? */
        int     x1, y1;                         /* p1 position */
        register int    x, y;                   /* final position */

                                        /* compute vector p0p1 */
        if (fillo&F_FORE && ABS(p1->z-p0->z) <= zt) {
                s1x = p1->x - p0->x;
                s1y = p1->y - p0->y;
                l1 = ABS(s1x);
                if (p1isy = (ABS(s1y) > l1))
                        l1 = ABS(s1y);
        } else {
                l1 = s1x = s1y = 1;
                p1isy = -1;
        }
                                        /* compute vector p0p2 */
        if (fillo&F_FORE && ABS(p2->z-p0->z) <= zt) {
                s2x = p2->x - p0->x;
                s2y = p2->y - p0->y;
                if (p1isy == 1)
                        l2 = ABS(s2x);
                else {
                        l2 = ABS(s2y);
                        if (p1isy != 0 && ABS(s2x) > l2)
                                l2 = ABS(s2x);
                }
        } else
                l2 = s2x = s2y = 1;
                                        /* fill the parallelogram */
        for (c1 = l1; c1-- > 0; ) {
                x1 = p0->x + c1*s1x/l1;
                y1 = p0->y + c1*s1y/l1;
                for (c2 = l2; c2-- > 0; ) {
                        x = x1 + c2*s2x/l2;
                        y = y1 + c2*s2y/l2;
                        if (zscan(y)[x] <= 0 || zscan(y)[x]-z
                                                > zeps*zscan(y)[x]) {
                                zscan(y)[x] = z;
                                copycolr(pscan(y)[x], pix);
                        }
                }
        }
}


backpicture(fill, samp)                 /* background fill algorithm */
int     (*fill)();
int     samp;
{
        int     *yback, xback;
        int     y;
        COLR    pfill;
        register int    x, i;
                                                        /* get back buffer */
        yback = (int *)malloc(hresolu*sizeof(int));
        if (yback == NULL)
                syserror();
        for (x = 0; x < hresolu; x++)
                yback[x] = -2;
        /*
         * Xback and yback are the pixel locations of suitable
         * background values in each direction.
         * A value of -2 means unassigned, and -1 means
         * that there is no suitable background in this direction.
         */
                                                        /* fill image */
        for (y = 0; y < vresolu; y++) {
                xback = -2;
                for (x = 0; x < hresolu; x++)
                        if (zscan(y)[x] <= 0) {         /* empty pixel */
                                /*
                                 * First, find background from above or below.
                                 * (farthest assigned pixel)
                                 */
                                if (yback[x] == -2) {
                                        for (i = y+1; i < vresolu; i++)
                                                if (zscan(i)[x] > 0)
                                                        break;
                                        if (i < vresolu
                                && (y <= 0 || zscan(y-1)[x] < zscan(i)[x]))
                                                yback[x] = i;
                                        else
                                                yback[x] = y-1;
                                }
                                /*
                                 * Next, find background from left or right.
                                 */
                                if (xback == -2) {
                                        for (i = x+1; i < hresolu; i++)
                                                if (zscan(y)[i] > 0)
                                                        break;
                                        if (i < hresolu
                                && (x <= 0 || zscan(y)[x-1] < zscan(y)[i]))
                                                xback = i;
                                        else
                                                xback = x-1;
                                }
                                /*
                                 * If we have no background for this pixel,
                                 * use the given fill function.
                                 */
                                if (xback < 0 && yback[x] < 0)
                                        goto fillit;
                                /*
                                 * Compare, and use the background that is
                                 * farther, unless one of them is next to us.
                                 * If the background is too distant, call
                                 * the fill function.
                                 */
                                if ( yback[x] < 0
                                        || (xback >= 0 && ABS(x-xback) <= 1)
                                        || ( ABS(y-yback[x]) > 1
                                                && zscan(yback[x])[x]
                                                < zscan(y)[xback] ) ) {
                                        if (samp > 0 && ABS(x-xback) >= samp)
                                                goto fillit;
                                        copycolr(pscan(y)[x],pscan(y)[xback]);
                                        zscan(y)[x] = zscan(y)[xback];
                                } else {
                                        if (samp > 0 && ABS(y-yback[x]) > samp)
                                                goto fillit;
                                        copycolr(pscan(y)[x],pscan(yback[x])[x]);
                                        zscan(y)[x] = zscan(yback[x])[x];
                                }
                                continue;
                        fillit:
                                (*fill)(x,y);
                                if (fill == rcalfill) {         /* use it */
                                        clearqueue();
                                        xback = x;
                                        yback[x] = y;
                                }
                        } else {                                /* full pixel */
                                yback[x] = -2;
                                xback = -2;
                        }
        }
        free((char *)yback);
}


fillpicture(fill)               /* paint in empty pixels using fill */
int     (*fill)();
{
        register int    x, y;

        for (y = 0; y < vresolu; y++)
                for (x = 0; x < hresolu; x++)
                        if (zscan(y)[x] <= 0)
                                (*fill)(x,y);
}


writepicture()                          /* write out picture */
{
        int     y;

        fputresolu(YMAJOR|YDECR, hresolu, vresolu, stdout);
        for (y = vresolu-1; y >= 0; y--)
                if (fwritecolrs(pscan(y), hresolu, stdout) < 0)
                        syserror();
}


writedistance(fname)                    /* write out z file */
char    *fname;
{
        extern double   sqrt();
        int     donorm = normdist && ourview.type == VT_PER;
        int     fd;
        int     y;
        float   *zout;

        if ((fd = open(fname, O_WRONLY|O_CREAT|O_TRUNC, 0666)) == -1) {
                perror(fname);
                exit(1);
        }
        if (donorm
        && (zout = (float *)malloc(hresolu*sizeof(float))) == NULL)
                syserror();
        for (y = vresolu-1; y >= 0; y--) {
                if (donorm) {
                        double  vx, yzn2;
                        register int    x;
                        yzn2 = y - .5*(vresolu-1);
                        yzn2 = 1. + yzn2*yzn2*ourview.vn2;
                        for (x = 0; x < hresolu; x++) {
                                vx = x - .5*(hresolu-1);
                                zout[x] = zscan(y)[x]
                                        * sqrt(vx*vx*ourview.hn2 + yzn2);
                        }
                } else
                        zout = zscan(y);
                if (write(fd, (char *)zout, hresolu*sizeof(float))
                                < hresolu*sizeof(float)) {
                        perror(fname);
                        exit(1);
                }
        }
        if (donorm)
                free((char *)zout);
        close(fd);
}


isfloat(s)                              /* see if string is floating number */
register char   *s;
{
        for ( ; *s; s++)
                if ((*s < '0' || *s > '9') && *s != '.' && *s != '-'
                                && *s != 'e' && *s != 'E' && *s != '+')
                        return(0);
        return(1);
}


backfill(x, y)                          /* fill pixel with background */
int     x, y;
{
        register BYTE   *dest = pscan(y)[x];

        copycolr(dest, backcolr);
        zscan(y)[x] = backz;
}


calstart(prog, args)                    /* start fill calculation */
char    *prog, *args;
{
        char    combuf[512];
        int     p0[2], p1[2];

        if (childpid != -1) {
                fprintf(stderr, "%s: too many calculations\n", progname);
                exit(1);
        }
        sprintf(combuf, prog, args);
        if (pipe(p0) < 0 || pipe(p1) < 0)
                syserror();
        if ((childpid = vfork()) == 0) {        /* fork calculation */
                close(p0[1]);
                close(p1[0]);
                if (p0[0] != 0) {
                        dup2(p0[0], 0);
                        close(p0[0]);
                }
                if (p1[1] != 1) {
                        dup2(p1[1], 1);
                        close(p1[1]);
                }
                execl("/bin/sh", "sh", "-c", combuf, 0);
                perror("/bin/sh");
                _exit(127);
        }
        if (childpid == -1)
                syserror();
        close(p0[0]);
        close(p1[1]);
        if ((psend = fdopen(p0[1], "w")) == NULL)
                syserror();
        if ((precv = fdopen(p1[0], "r")) == NULL)
                syserror();
        queuesiz = 0;
}


caldone()                               /* done with calculation */
{
        int     pid;

        if (childpid == -1)
                return;
        clearqueue();
        fclose(psend);
        fclose(precv);
        while ((pid = wait(0)) != -1 && pid != childpid)
                ;
        childpid = -1;
}


rcalfill(x, y)                          /* fill with ray-calculated pixel */
int     x, y;
{
        if (queuesiz >= PACKSIZ)        /* flush queue if needed */
                clearqueue();
                                        /* add position to queue */
        queue[queuesiz][0] = x;
        queue[queuesiz][1] = y;
        queuesiz++;
}


clearqueue()                            /* process queue */
{
        FVECT   orig, dir;
        float   fbuf[6];
        register int    i;

        for (i = 0; i < queuesiz; i++) {
                viewray(orig, dir, &ourview,
                                (queue[i][0]+.5)/hresolu,
                                (queue[i][1]+.5)/vresolu);
                fbuf[0] = orig[0]; fbuf[1] = orig[1]; fbuf[2] = orig[2];
                fbuf[3] = dir[0]; fbuf[4] = dir[1]; fbuf[5] = dir[2];
                fwrite((char *)fbuf, sizeof(float), 6, psend);
        }
                                        /* flush output and get results */
        fbuf[3] = fbuf[4] = fbuf[5] = 0.0;              /* mark */
        fwrite((char *)fbuf, sizeof(float), 6, psend);
        if (fflush(psend) == EOF)
                syserror();
        for (i = 0; i < queuesiz; i++) {
                if (fread((char *)fbuf, sizeof(float), 4, precv) < 4) {
                        fprintf(stderr, "%s: read error in clearqueue\n",
                                        progname);
                        exit(1);
                }
                if (ourexp > 0 && ourexp != 1.0) {
                        fbuf[0] *= ourexp;
                        fbuf[1] *= ourexp;
                        fbuf[2] *= ourexp;
                }
                setcolr(pscan(queue[i][1])[queue[i][0]],
                                fbuf[0], fbuf[1], fbuf[2]);
                zscan(queue[i][1])[queue[i][0]] = fbuf[3];
        }
        queuesiz = 0;
}


syserror()                      /* report error and exit */
{
        perror(progname);
        exit(1);
}
Revision:	1.27
Committed:	Tue Mar 6 15:45:31 1990 UTC (34 years, 2 months ago) by greg
Content type:	text/plain
Branch:	MAIN
Changes since 1.26:	+16 -12 lines
Log Message:	fixed sampling so samples are reused as background
#	User	Rev	Content
1	greg	1.1	#ifndef lint
2			static char SCCSid[] = "$SunId$ LBL";
3			#endif
4
5			/*
6			* Interpolate and extrapolate pictures with different view parameters.
7			*
8			* Greg Ward 09Dec89
9			*/
10
11			#include "standard.h"
12
13	greg	1.24	#include <fcntl.h>
14	greg	1.19
15	greg	1.1	#include "view.h"
16
17			#include "color.h"
18
19	greg	1.21	#ifndef BSD
20			#define vfork fork
21			#endif
22
23	greg	1.17	#define pscan(y) (ourpict+(y)*hresolu)
24			#define zscan(y) (ourzbuf+(y)*hresolu)
25	greg	1.1
26	greg	1.13	#define F_FORE 1 /* fill foreground */
27			#define F_BACK 2 /* fill background */
28	greg	1.11
29	greg	1.13	#define PACKSIZ 42 /* calculation packet size */
30
31	greg	1.25	#define RTCOM "rtrace -h -ovl -fff %s"
32	greg	1.13
33	greg	1.3	#define ABS(x) ((x)>0?(x):-(x))
34
35	greg	1.15	struct position {int x,y; float z;};
36
37	greg	1.17	VIEW ourview = STDVIEW; /* desired view */
38			int hresolu = 512; /* horizontal resolution */
39			int vresolu = 512; /* vertical resolution */
40	greg	1.18	double pixaspect = 1.0; /* pixel aspect ratio */
41	greg	1.1
42	greg	1.8	double zeps = .02; /* allowed z epsilon */
43	greg	1.1
44			COLR ourpict; / output picture */
45			float ourzbuf; / corresponding z-buffer */
46
47			char *progname;
48
49	greg	1.25	int fillo = F_FORE\|F_BACK; /* selected fill options */
50	greg	1.26	int fillsamp = 0; /* sample separation (0 == inf) */
51	greg	1.14	extern int backfill(), rcalfill(); /* fill functions */
52	greg	1.25	int (fillfunc)() = backfill; / selected fill function */
53	greg	1.11	COLR backcolr = BLKCOLR; /* background color */
54	greg	1.13	double backz = 0.0; /* background z value */
55	greg	1.16	int normdist = 1; /* normalized distance? */
56			double ourexp = -1; /* output picture exposure */
57	greg	1.11
58	greg	1.17	VIEW theirview = STDVIEW; /* input view */
59	greg	1.16	int gotview; /* got input view? */
60	greg	1.17	int thresolu, tvresolu; /* input resolution */
61			double theirexp; /* input picture exposure */
62	greg	1.5	double theirs2ours[4][4]; /* transformation matrix */
63	greg	1.1
64	greg	1.14	int childpid = -1; /* id of fill process */
65	greg	1.13	FILE psend, precv; /* pipes to/from fill calculation */
66			int queue[PACKSIZ][2]; /* pending pixels */
67			int queuesiz; /* number of pixels pending */
68	greg	1.5
69	greg	1.13
70	greg	1.1	main(argc, argv) /* interpolate pictures */
71			int argc;
72			char *argv[];
73			{
74			#define check(olen,narg) if (argv[i][olen] \|\| narg >= argc-i) goto badopt
75	greg	1.11	extern double atof();
76	greg	1.1	int gotvfile = 0;
77	greg	1.11	char *zfile = NULL;
78	greg	1.1	char *err;
79	greg	1.17	int i, rval;
80	greg	1.1
81			progname = argv[0];
82
83	greg	1.17	for (i = 1; i < argc && argv[i][0] == '-'; i++) {
84			rval = getviewopt(&ourview, argc-i, argv+i);
85			if (rval >= 0) {
86			i += rval;
87			continue;
88			}
89	greg	1.1	switch (argv[i][1]) {
90			case 't': /* threshold */
91			check(2,1);
92			zeps = atof(argv[++i]);
93			break;
94	greg	1.11	case 'n': /* dist. normalized? */
95	greg	1.10	check(2,0);
96	greg	1.11	normdist = !normdist;
97	greg	1.10	break;
98	greg	1.11	case 'f': /* fill type */
99			switch (argv[i][2]) {
100			case '0': /* none */
101			check(3,0);
102	greg	1.25	fillo = 0;
103	greg	1.11	break;
104			case 'f': /* foreground */
105			check(3,0);
106	greg	1.25	fillo = F_FORE;
107	greg	1.11	break;
108			case 'b': /* background */
109			check(3,0);
110	greg	1.25	fillo = F_BACK;
111	greg	1.11	break;
112			case 'a': /* all */
113			check(3,0);
114	greg	1.25	fillo = F_FORE\|F_BACK;
115	greg	1.11	break;
116	greg	1.25	case 's': /* sample */
117			check(3,1);
118	greg	1.26	fillsamp = atoi(argv[++i]);
119	greg	1.25	break;
120	greg	1.11	case 'c': /* color */
121			check(3,3);
122	greg	1.25	fillfunc = backfill;
123	greg	1.11	setcolr(backcolr, atof(argv[i+1]),
124			atof(argv[i+2]), atof(argv[i+3]));
125			i += 3;
126			break;
127	greg	1.13	case 'z': /* z value */
128			check(3,1);
129	greg	1.25	fillfunc = backfill;
130	greg	1.13	backz = atof(argv[++i]);
131			break;
132			case 'r': /* rtrace */
133			check(3,1);
134	greg	1.25	fillfunc = rcalfill;
135	greg	1.13	calstart(RTCOM, argv[++i]);
136			break;
137	greg	1.11	default:
138			goto badopt;
139			}
140			break;
141			case 'z': /* z file */
142			check(2,1);
143			zfile = argv[++i];
144			break;
145	greg	1.6	case 'x': /* x resolution */
146			check(2,1);
147	greg	1.17	hresolu = atoi(argv[++i]);
148	greg	1.6	break;
149			case 'y': /* y resolution */
150			check(2,1);
151	greg	1.17	vresolu = atoi(argv[++i]);
152	greg	1.6	break;
153	greg	1.18	case 'p': /* pixel aspect */
154			check(2,1);
155			pixaspect = atof(argv[++i]);
156			break;
157	greg	1.17	case 'v': /* view file */
158			if (argv[i][2] != 'f')
159	greg	1.1	goto badopt;
160	greg	1.17	check(3,1);
161	greg	1.19	gotvfile = viewfile(argv[++i], &ourview, 0, 0);
162	greg	1.17	if (gotvfile < 0) {
163			perror(argv[i]);
164			exit(1);
165			} else if (gotvfile == 0) {
166			fprintf(stderr, "%s: bad view file\n",
167			argv[i]);
168			exit(1);
169	greg	1.1	}
170			break;
171			default:
172			badopt:
173	greg	1.10	fprintf(stderr, "%s: command line error at '%s'\n",
174	greg	1.1	progname, argv[i]);
175	greg	1.10	goto userr;
176	greg	1.1	}
177	greg	1.17	}
178	greg	1.1	/* check arguments */
179	greg	1.13	if ((argc-i)%2)
180	greg	1.10	goto userr;
181	greg	1.1	/* set view */
182			if (err = setview(&ourview)) {
183			fprintf(stderr, "%s: %s\n", progname, err);
184			exit(1);
185			}
186	greg	1.18	normaspect(viewaspect(&ourview), &pixaspect, &hresolu, &vresolu);
187	greg	1.1	/* allocate frame */
188	greg	1.17	ourpict = (COLR )malloc(hresoluvresolu*sizeof(COLR));
189			ourzbuf = (float )calloc(hresoluvresolu,sizeof(float));
190	greg	1.15	if (ourpict == NULL \|\| ourzbuf == NULL)
191			syserror();
192	greg	1.1	/* get input */
193			for ( ; i < argc; i += 2)
194			addpicture(argv[i], argv[i+1]);
195			/* fill in spaces */
196	greg	1.25	if (fillo&F_BACK)
197	greg	1.26	backpicture(fillfunc, fillsamp);
198	greg	1.12	else
199	greg	1.25	fillpicture(fillfunc);
200	greg	1.13	/* close calculation */
201	greg	1.14	caldone();
202	greg	1.1	/* add to header */
203			printargs(argc, argv, stdout);
204			if (gotvfile) {
205	greg	1.25	fputs(VIEWSTR, stdout);
206	greg	1.1	fprintview(&ourview, stdout);
207	greg	1.25	putc('\n', stdout);
208	greg	1.1	}
209	greg	1.18	if (pixaspect < .99 \|\| pixaspect > 1.01)
210			fputaspect(pixaspect, stdout);
211			if (ourexp > 0 && (ourexp < .995 \|\| ourexp > 1.005))
212	greg	1.16	fputexpos(ourexp, stdout);
213	greg	1.25	putc('\n', stdout);
214	greg	1.11	/* write picture */
215	greg	1.1	writepicture();
216	greg	1.11	/* write z file */
217			if (zfile != NULL)
218			writedistance(zfile);
219	greg	1.1
220			exit(0);
221	greg	1.10	userr:
222			fprintf(stderr,
223	greg	1.17	"Usage: %s [view opts][-t eps][-z zout][-fT][-n] pfile zspec ..\n",
224	greg	1.10	progname);
225			exit(1);
226	greg	1.1	#undef check
227			}
228
229
230			headline(s) /* process header string */
231			char *s;
232			{
233	greg	1.25	static char *altname[] = {VIEWSTR,"rpict","rview","pinterp",NULL};
234	greg	1.1	register char **an;
235
236	greg	1.25	putc('\t', stdout);
237			fputs(s, stdout);
238	greg	1.1
239	greg	1.16	if (isexpos(s)) {
240			theirexp *= exposval(s);
241			return;
242			}
243	greg	1.1	for (an = altname; *an != NULL; an++)
244			if (!strncmp(an, s, strlen(an))) {
245	greg	1.17	if (sscanview(&theirview, s+strlen(*an)) > 0)
246	greg	1.1	gotview++;
247			break;
248			}
249			}
250
251
252	greg	1.10	addpicture(pfile, zspec) /* add picture to output */
253			char pfile, zspec;
254	greg	1.1	{
255	greg	1.10	extern double atof();
256	greg	1.19	FILE *pfp;
257			int zfd;
258	greg	1.8	char *err;
259	greg	1.1	COLR *scanin;
260	greg	1.15	float *zin;
261			struct position *plast;
262	greg	1.1	int y;
263	greg	1.10	/* open picture file */
264	greg	1.1	if ((pfp = fopen(pfile, "r")) == NULL) {
265			perror(pfile);
266			exit(1);
267			}
268	greg	1.16	/* get header with exposure and view */
269			theirexp = 1.0;
270			gotview = 0;
271	greg	1.1	printf("%s:\n", pfile);
272			getheader(pfp, headline);
273	greg	1.17	if (!gotview \|\| fgetresolu(&thresolu, &tvresolu, pfp)
274	greg	1.9	!= (YMAJOR\|YDECR)) {
275	greg	1.1	fprintf(stderr, "%s: picture view error\n", pfile);
276			exit(1);
277			}
278	greg	1.16	if (ourexp <= 0)
279			ourexp = theirexp;
280			else if (ABS(theirexp-ourexp) > .01*ourexp)
281			fprintf(stderr, "%s: different exposure (warning)\n", pfile);
282	greg	1.1	if (err = setview(&theirview)) {
283			fprintf(stderr, "%s: %s\n", pfile, err);
284			exit(1);
285			}
286	greg	1.5	/* compute transformation */
287			pixform(theirs2ours, &theirview, &ourview);
288	greg	1.1	/* allocate scanlines */
289	greg	1.17	scanin = (COLR )malloc(thresolusizeof(COLR));
290			zin = (float )malloc(thresolusizeof(float));
291			plast = (struct position *)calloc(thresolu, sizeof(struct position));
292	greg	1.15	if (scanin == NULL \|\| zin == NULL \|\| plast == NULL)
293			syserror();
294	greg	1.10	/* get z specification or file */
295	greg	1.19	if ((zfd = open(zspec, O_RDONLY)) == -1) {
296	greg	1.10	double zvalue;
297			register int x;
298			if (!isfloat(zspec) \|\| (zvalue = atof(zspec)) <= 0.0) {
299			perror(zspec);
300			exit(1);
301			}
302	greg	1.17	for (x = 0; x < thresolu; x++)
303	greg	1.10	zin[x] = zvalue;
304			}
305	greg	1.1	/* load image */
306	greg	1.17	for (y = tvresolu-1; y >= 0; y--) {
307			if (freadcolrs(scanin, thresolu, pfp) < 0) {
308	greg	1.1	fprintf(stderr, "%s: read error\n", pfile);
309			exit(1);
310			}
311	greg	1.23	if (zfd != -1 && read(zfd,(char )zin,thresolusizeof(float))
312	greg	1.19	< thresolu*sizeof(float)) {
313	greg	1.10	fprintf(stderr, "%s: read error\n", zspec);
314	greg	1.1	exit(1);
315			}
316	greg	1.15	addscanline(y, scanin, zin, plast);
317	greg	1.1	}
318			/* clean up */
319			free((char *)scanin);
320			free((char *)zin);
321	greg	1.9	free((char *)plast);
322	greg	1.1	fclose(pfp);
323	greg	1.19	if (zfd != -1)
324			close(zfd);
325	greg	1.1	}
326
327
328	greg	1.5	pixform(xfmat, vw1, vw2) /* compute view1 to view2 matrix */
329			register double xfmat[4][4];
330			register VIEW vw1, vw2;
331			{
332			double m4t[4][4];
333
334			setident4(xfmat);
335	greg	1.17	xfmat[0][0] = vw1->hvec[0];
336			xfmat[0][1] = vw1->hvec[1];
337			xfmat[0][2] = vw1->hvec[2];
338			xfmat[1][0] = vw1->vvec[0];
339			xfmat[1][1] = vw1->vvec[1];
340			xfmat[1][2] = vw1->vvec[2];
341	greg	1.5	xfmat[2][0] = vw1->vdir[0];
342			xfmat[2][1] = vw1->vdir[1];
343			xfmat[2][2] = vw1->vdir[2];
344			xfmat[3][0] = vw1->vp[0];
345			xfmat[3][1] = vw1->vp[1];
346			xfmat[3][2] = vw1->vp[2];
347			setident4(m4t);
348	greg	1.17	m4t[0][0] = vw2->hvec[0]/vw2->hn2;
349			m4t[1][0] = vw2->hvec[1]/vw2->hn2;
350			m4t[2][0] = vw2->hvec[2]/vw2->hn2;
351			m4t[3][0] = -DOT(vw2->vp,vw2->hvec)/vw2->hn2;
352			m4t[0][1] = vw2->vvec[0]/vw2->vn2;
353			m4t[1][1] = vw2->vvec[1]/vw2->vn2;
354			m4t[2][1] = vw2->vvec[2]/vw2->vn2;
355			m4t[3][1] = -DOT(vw2->vp,vw2->vvec)/vw2->vn2;
356	greg	1.5	m4t[0][2] = vw2->vdir[0];
357			m4t[1][2] = vw2->vdir[1];
358			m4t[2][2] = vw2->vdir[2];
359			m4t[3][2] = -DOT(vw2->vp,vw2->vdir);
360			multmat4(xfmat, xfmat, m4t);
361			}
362
363
364	greg	1.15	addscanline(y, pline, zline, lasty) /* add scanline to output */
365	greg	1.1	int y;
366			COLR *pline;
367			float *zline;
368	greg	1.15	struct position lasty; / input/output */
369	greg	1.1	{
370	greg	1.11	extern double sqrt();
371	greg	1.5	double pos[3];
372	greg	1.15	struct position lastx, newpos;
373	greg	1.1	register int x;
374
375	greg	1.20	lastx.z = 0;
376	greg	1.17	for (x = thresolu-1; x >= 0; x--) {
377			pos[0] = (x+.5)/thresolu + theirview.hoff - .5;
378			pos[1] = (y+.5)/tvresolu + theirview.voff - .5;
379	greg	1.5	pos[2] = zline[x];
380			if (theirview.type == VT_PER) {
381	greg	1.11	if (normdist) /* adjust for eye-ray distance */
382	greg	1.10	pos[2] /= sqrt( 1.
383	greg	1.17	+ pos[0]pos[0]theirview.hn2
384			+ pos[1]pos[1]theirview.vn2 );
385	greg	1.5	pos[0] *= pos[2];
386			pos[1] *= pos[2];
387			}
388			multp3(pos, pos, theirs2ours);
389	greg	1.15	if (pos[2] <= 0) {
390			lasty[x].z = lastx.z = 0; /* mark invalid */
391	greg	1.1	continue;
392	greg	1.15	}
393	greg	1.5	if (ourview.type == VT_PER) {
394			pos[0] /= pos[2];
395			pos[1] /= pos[2];
396			}
397	greg	1.17	pos[0] += .5 - ourview.hoff;
398			pos[1] += .5 - ourview.voff;
399			newpos.x = pos[0] * hresolu;
400			newpos.y = pos[1] * vresolu;
401	greg	1.15	newpos.z = zline[x];
402	greg	1.8	/* add pixel to our image */
403	greg	1.17	if (pos[0] >= 0 && newpos.x < hresolu
404			&& pos[1] >= 0 && newpos.y < vresolu) {
405	greg	1.15	addpixel(&newpos, &lastx, &lasty[x], pline[x], pos[2]);
406			lasty[x].x = lastx.x = newpos.x;
407			lasty[x].y = lastx.y = newpos.y;
408			lasty[x].z = lastx.z = newpos.z;
409			} else
410			lasty[x].z = lastx.z = 0; /* mark invalid */
411	greg	1.1	}
412			}
413
414
415	greg	1.15	addpixel(p0, p1, p2, pix, z) /* fill in pixel parallelogram */
416			struct position p0, p1, *p2;
417	greg	1.8	COLR pix;
418			double z;
419			{
420	greg	1.15	double zt = 2.zepsp0->z; /* threshold */
421			int s1x, s1y, s2x, s2y; /* step sizes */
422			int l1, l2, c1, c2; /* side lengths and counters */
423			int p1isy; /* p0p1 along y? */
424			int x1, y1; /* p1 position */
425			register int x, y; /* final position */
426
427			/* compute vector p0p1 */
428	greg	1.25	if (fillo&F_FORE && ABS(p1->z-p0->z) <= zt) {
429	greg	1.15	s1x = p1->x - p0->x;
430			s1y = p1->y - p0->y;
431			l1 = ABS(s1x);
432			if (p1isy = (ABS(s1y) > l1))
433			l1 = ABS(s1y);
434			} else {
435			l1 = s1x = s1y = 1;
436			p1isy = -1;
437			}
438			/* compute vector p0p2 */
439	greg	1.25	if (fillo&F_FORE && ABS(p2->z-p0->z) <= zt) {
440	greg	1.15	s2x = p2->x - p0->x;
441			s2y = p2->y - p0->y;
442			if (p1isy == 1)
443			l2 = ABS(s2x);
444			else {
445			l2 = ABS(s2y);
446			if (p1isy != 0 && ABS(s2x) > l2)
447			l2 = ABS(s2x);
448			}
449			} else
450			l2 = s2x = s2y = 1;
451			/* fill the parallelogram */
452			for (c1 = l1; c1-- > 0; ) {
453			x1 = p0->x + c1*s1x/l1;
454			y1 = p0->y + c1*s1y/l1;
455			for (c2 = l2; c2-- > 0; ) {
456			x = x1 + c2*s2x/l2;
457			y = y1 + c2*s2y/l2;
458			if (zscan(y)[x] <= 0 \|\| zscan(y)[x]-z
459			> zeps*zscan(y)[x]) {
460	greg	1.8	zscan(y)[x] = z;
461			copycolr(pscan(y)[x], pix);
462			}
463	greg	1.15	}
464			}
465	greg	1.8	}
466
467
468	greg	1.26	backpicture(fill, samp) /* background fill algorithm */
469	greg	1.25	int (*fill)();
470	greg	1.26	int samp;
471	greg	1.1	{
472	greg	1.2	int *yback, xback;
473	greg	1.1	int y;
474	greg	1.2	COLR pfill;
475			register int x, i;
476			/* get back buffer */
477	greg	1.17	yback = (int )malloc(hresolusizeof(int));
478	greg	1.15	if (yback == NULL)
479			syserror();
480	greg	1.17	for (x = 0; x < hresolu; x++)
481	greg	1.4	yback[x] = -2;
482	greg	1.7	/*
483			* Xback and yback are the pixel locations of suitable
484			* background values in each direction.
485			* A value of -2 means unassigned, and -1 means
486			* that there is no suitable background in this direction.
487			*/
488	greg	1.2	/* fill image */
489	greg	1.17	for (y = 0; y < vresolu; y++) {
490	greg	1.4	xback = -2;
491	greg	1.17	for (x = 0; x < hresolu; x++)
492	greg	1.8	if (zscan(y)[x] <= 0) { /* empty pixel */
493	greg	1.7	/*
494			* First, find background from above or below.
495			* (farthest assigned pixel)
496			*/
497	greg	1.4	if (yback[x] == -2) {
498	greg	1.17	for (i = y+1; i < vresolu; i++)
499	greg	1.8	if (zscan(i)[x] > 0)
500	greg	1.4	break;
501	greg	1.17	if (i < vresolu
502	greg	1.2	&& (y <= 0 \|\| zscan(y-1)[x] < zscan(i)[x]))
503	greg	1.4	yback[x] = i;
504			else
505			yback[x] = y-1;
506	greg	1.2	}
507	greg	1.7	/*
508			* Next, find background from left or right.
509			*/
510	greg	1.4	if (xback == -2) {
511	greg	1.17	for (i = x+1; i < hresolu; i++)
512	greg	1.8	if (zscan(y)[i] > 0)
513	greg	1.4	break;
514	greg	1.17	if (i < hresolu
515	greg	1.4	&& (x <= 0 \|\| zscan(y)[x-1] < zscan(y)[i]))
516			xback = i;
517			else
518			xback = x-1;
519			}
520	greg	1.7	/*
521	greg	1.26	* If we have no background for this pixel,
522			* use the given fill function.
523	greg	1.11	*/
524	greg	1.27	if (xback < 0 && yback[x] < 0)
525			goto fillit;
526	greg	1.11	/*
527	greg	1.7	* Compare, and use the background that is
528			* farther, unless one of them is next to us.
529	greg	1.27	* If the background is too distant, call
530			* the fill function.
531	greg	1.7	*/
532	greg	1.11	if ( yback[x] < 0
533			\|\| (xback >= 0 && ABS(x-xback) <= 1)
534	greg	1.4	\|\| ( ABS(y-yback[x]) > 1
535	greg	1.11	&& zscan(yback[x])[x]
536	greg	1.13	< zscan(y)[xback] ) ) {
537	greg	1.27	if (samp > 0 && ABS(x-xback) >= samp)
538			goto fillit;
539	greg	1.4	copycolr(pscan(y)[x],pscan(y)[xback]);
540	greg	1.13	zscan(y)[x] = zscan(y)[xback];
541			} else {
542	greg	1.27	if (samp > 0 && ABS(y-yback[x]) > samp)
543			goto fillit;
544	greg	1.4	copycolr(pscan(y)[x],pscan(yback[x])[x]);
545	greg	1.13	zscan(y)[x] = zscan(yback[x])[x];
546	greg	1.27	}
547			continue;
548			fillit:
549			(*fill)(x,y);
550			if (fill == rcalfill) { /* use it */
551			clearqueue();
552			xback = x;
553			yback[x] = y;
554	greg	1.13	}
555	greg	1.4	} else { /* full pixel */
556			yback[x] = -2;
557			xback = -2;
558			}
559			}
560	greg	1.2	free((char *)yback);
561	greg	1.1	}
562
563
564	greg	1.25	fillpicture(fill) /* paint in empty pixels using fill */
565			int (*fill)();
566	greg	1.11	{
567			register int x, y;
568
569	greg	1.17	for (y = 0; y < vresolu; y++)
570			for (x = 0; x < hresolu; x++)
571	greg	1.11	if (zscan(y)[x] <= 0)
572	greg	1.25	(*fill)(x,y);
573	greg	1.11	}
574
575
576	greg	1.1	writepicture() /* write out picture */
577			{
578			int y;
579
580	greg	1.17	fputresolu(YMAJOR\|YDECR, hresolu, vresolu, stdout);
581			for (y = vresolu-1; y >= 0; y--)
582			if (fwritecolrs(pscan(y), hresolu, stdout) < 0)
583	greg	1.15	syserror();
584	greg	1.11	}
585
586
587			writedistance(fname) /* write out z file */
588			char *fname;
589			{
590			extern double sqrt();
591			int donorm = normdist && ourview.type == VT_PER;
592	greg	1.19	int fd;
593	greg	1.11	int y;
594			float *zout;
595
596	greg	1.19	if ((fd = open(fname, O_WRONLY\|O_CREAT\|O_TRUNC, 0666)) == -1) {
597	greg	1.11	perror(fname);
598			exit(1);
599			}
600			if (donorm
601	greg	1.17	&& (zout = (float )malloc(hresolusizeof(float))) == NULL)
602	greg	1.15	syserror();
603	greg	1.17	for (y = vresolu-1; y >= 0; y--) {
604	greg	1.11	if (donorm) {
605			double vx, yzn2;
606			register int x;
607	greg	1.17	yzn2 = y - .5*(vresolu-1);
608			yzn2 = 1. + yzn2yzn2ourview.vn2;
609			for (x = 0; x < hresolu; x++) {
610			vx = x - .5*(hresolu-1);
611	greg	1.11	zout[x] = zscan(y)[x]
612	greg	1.17	* sqrt(vxvxourview.hn2 + yzn2);
613	greg	1.11	}
614			} else
615			zout = zscan(y);
616	greg	1.23	if (write(fd, (char )zout, hresolusizeof(float))
617	greg	1.19	< hresolu*sizeof(float)) {
618	greg	1.11	perror(fname);
619			exit(1);
620			}
621			}
622			if (donorm)
623			free((char *)zout);
624	greg	1.19	close(fd);
625	greg	1.10	}
626
627
628			isfloat(s) /* see if string is floating number */
629			register char *s;
630			{
631			for ( ; *s; s++)
632			if ((s < '0' \|\| s > '9') && s != '.' && s != '-'
633			&& s != 'e' && s != 'E' && *s != '+')
634			return(0);
635			return(1);
636	greg	1.12	}
637
638
639			backfill(x, y) /* fill pixel with background */
640			int x, y;
641			{
642			register BYTE *dest = pscan(y)[x];
643
644			copycolr(dest, backcolr);
645	greg	1.13	zscan(y)[x] = backz;
646			}
647
648
649			calstart(prog, args) /* start fill calculation */
650			char prog, args;
651			{
652			char combuf[512];
653			int p0[2], p1[2];
654
655	greg	1.14	if (childpid != -1) {
656			fprintf(stderr, "%s: too many calculations\n", progname);
657			exit(1);
658			}
659	greg	1.25	sprintf(combuf, prog, args);
660	greg	1.13	if (pipe(p0) < 0 \|\| pipe(p1) < 0)
661	greg	1.14	syserror();
662	greg	1.13	if ((childpid = vfork()) == 0) { /* fork calculation */
663			close(p0[1]);
664			close(p1[0]);
665			if (p0[0] != 0) {
666			dup2(p0[0], 0);
667			close(p0[0]);
668			}
669			if (p1[1] != 1) {
670			dup2(p1[1], 1);
671			close(p1[1]);
672			}
673			execl("/bin/sh", "sh", "-c", combuf, 0);
674			perror("/bin/sh");
675			_exit(127);
676			}
677	greg	1.14	if (childpid == -1)
678			syserror();
679	greg	1.13	close(p0[0]);
680			close(p1[1]);
681			if ((psend = fdopen(p0[1], "w")) == NULL)
682	greg	1.14	syserror();
683	greg	1.13	if ((precv = fdopen(p1[0], "r")) == NULL)
684	greg	1.14	syserror();
685	greg	1.13	queuesiz = 0;
686			}
687
688
689			caldone() /* done with calculation */
690			{
691			int pid;
692
693	greg	1.14	if (childpid == -1)
694			return;
695	greg	1.25	clearqueue();
696			fclose(psend);
697			fclose(precv);
698	greg	1.13	while ((pid = wait(0)) != -1 && pid != childpid)
699			;
700	greg	1.14	childpid = -1;
701	greg	1.13	}
702
703
704	greg	1.14	rcalfill(x, y) /* fill with ray-calculated pixel */
705	greg	1.13	int x, y;
706			{
707	greg	1.22	if (queuesiz >= PACKSIZ) /* flush queue if needed */
708	greg	1.25	clearqueue();
709	greg	1.22	/* add position to queue */
710	greg	1.13	queue[queuesiz][0] = x;
711			queue[queuesiz][1] = y;
712			queuesiz++;
713			}
714
715
716	greg	1.25	clearqueue() /* process queue */
717	greg	1.13	{
718	greg	1.22	FVECT orig, dir;
719			float fbuf[6];
720	greg	1.13	register int i;
721
722			for (i = 0; i < queuesiz; i++) {
723	greg	1.22	viewray(orig, dir, &ourview,
724			(queue[i][0]+.5)/hresolu,
725			(queue[i][1]+.5)/vresolu);
726			fbuf[0] = orig[0]; fbuf[1] = orig[1]; fbuf[2] = orig[2];
727			fbuf[3] = dir[0]; fbuf[4] = dir[1]; fbuf[5] = dir[2];
728	greg	1.23	fwrite((char *)fbuf, sizeof(float), 6, psend);
729	greg	1.22	}
730	greg	1.25	/* flush output and get results */
731			fbuf[3] = fbuf[4] = fbuf[5] = 0.0; /* mark */
732			fwrite((char *)fbuf, sizeof(float), 6, psend);
733			if (fflush(psend) == EOF)
734	greg	1.22	syserror();
735			for (i = 0; i < queuesiz; i++) {
736	greg	1.23	if (fread((char *)fbuf, sizeof(float), 4, precv) < 4) {
737	greg	1.14	fprintf(stderr, "%s: read error in clearqueue\n",
738			progname);
739			exit(1);
740	greg	1.16	}
741			if (ourexp > 0 && ourexp != 1.0) {
742	greg	1.22	fbuf[0] *= ourexp;
743			fbuf[1] *= ourexp;
744			fbuf[2] *= ourexp;
745	greg	1.14	}
746	greg	1.13	setcolr(pscan(queue[i][1])[queue[i][0]],
747	greg	1.22	fbuf[0], fbuf[1], fbuf[2]);
748			zscan(queue[i][1])[queue[i][0]] = fbuf[3];
749	greg	1.13	}
750			queuesiz = 0;
751	greg	1.14	}
752
753
754			syserror() /* report error and exit */
755			{
756			perror(progname);
757			exit(1);
758	greg	1.1	}