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 -x %d %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     fill = F_FORE|F_BACK;           /* selected fill algorithm */
extern int      backfill(), rcalfill(); /* fill functions */
int     (*deffill)() = 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);
                                fill = 0;
                                break;
                        case 'f':                               /* foreground */
                                check(3,0);
                                fill = F_FORE;
                                break;
                        case 'b':                               /* background */
                                check(3,0);
                                fill = F_BACK;
                                break;
                        case 'a':                               /* all */
                                check(3,0);
                                fill = F_FORE|F_BACK;
                                break;
                        case 'c':                               /* color */
                                check(3,3);
                                deffill = 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);
                                deffill = backfill;
                                backz = atof(argv[++i]);
                                break;
                        case 'r':                               /* rtrace */
                                check(3,1);
                                deffill = 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 (fill&F_BACK)
                backpicture();
        else
                fillpicture();
                                                        /* close calculation */
        caldone();
                                                        /* add to header */
        printargs(argc, argv, stdout);
        if (gotvfile) {
                printf(VIEWSTR);
                fprintview(&ourview, stdout);
                printf("\n");
        }
        if (pixaspect < .99 || pixaspect > 1.01)
                fputaspect(pixaspect, stdout);
        if (ourexp > 0 && (ourexp < .995 || ourexp > 1.005))
                fputexpos(ourexp, stdout);
        printf("\n");
                                                        /* 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[] = {"rview","rpict","pinterp",VIEWSTR,NULL};
        register char   **an;

        printf("\t%s", s);

        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 (fill&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 (fill&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()                           /* background fill algorithm */
{
        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;
                                }
                                /*
                                 * Check to see if we have no background for
                                 * this pixel.  If not, use background color.
                                 */
                                if (xback < 0 && yback[x] < 0) {
                                        (*deffill)(x,y);
                                        continue;
                                }
                                /*
                                 * Compare, and use the background that is
                                 * farther, unless one of them is next to us.
                                 */
                                if ( yback[x] < 0
                                        || (xback >= 0 && ABS(x-xback) <= 1)
                                        || ( ABS(y-yback[x]) > 1
                                                && zscan(yback[x])[x]
                                                < zscan(y)[xback] ) ) {
                                        copycolr(pscan(y)[x],pscan(y)[xback]);
                                        zscan(y)[x] = zscan(y)[xback];
                                } else {
                                        copycolr(pscan(y)[x],pscan(yback[x])[x]);
                                        zscan(y)[x] = zscan(yback[x])[x];
                                }
                        } else {                                /* full pixel */
                                yback[x] = -2;
                                xback = -2;
                        }
        }
        free((char *)yback);
}


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

        for (y = 0; y < vresolu; y++)
                for (x = 0; x < hresolu; x++)
                        if (zscan(y)[x] <= 0)
                                (*deffill)(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, PACKSIZ, 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(1);
        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(0);
                                        /* add position to queue */
        queue[queuesiz][0] = x;
        queue[queuesiz][1] = y;
        queuesiz++;
}


clearqueue(done)                        /* process queue */
int     done;
{
        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);
        }
        if ((done ? fclose(psend) : 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];
        }
        if (done)
                fclose(precv);
        queuesiz = 0;
}


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