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 "view.h"

#include "color.h"

#define pscan(y)        (ourpict+(y)*ourview.hresolu)
#define zscan(y)        (ourzbuf+(y)*ourview.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(512);         /* desired view */

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(512);       /* input view */
int     gotview;                        /* got input view? */
double  theirs2ours[4][4];              /* transformation matrix */
double  theirexp;                       /* input picture exposure */

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;

        progname = argv[0];

        for (i = 1; i < argc && argv[i][0] == '-'; i++)
                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);
                        ourview.hresolu = atoi(argv[++i]);
                        break;
                case 'y':                               /* y resolution */
                        check(2,1);
                        ourview.vresolu = atoi(argv[++i]);
                        break;
                case 'v':                               /* view */
                        switch (argv[i][2]) {
                        case 't':                               /* type */
                                check(4,0);
                                ourview.type = argv[i][3];
                                break;
                        case 'p':                               /* point */
                                check(3,3);
                                ourview.vp[0] = atof(argv[++i]);
                                ourview.vp[1] = atof(argv[++i]);
                                ourview.vp[2] = atof(argv[++i]);
                                break;
                        case 'd':                               /* direction */
                                check(3,3);
                                ourview.vdir[0] = atof(argv[++i]);
                                ourview.vdir[1] = atof(argv[++i]);
                                ourview.vdir[2] = atof(argv[++i]);
                                break;
                        case 'u':                               /* up */
                                check(3,3);
                                ourview.vup[0] = atof(argv[++i]);
                                ourview.vup[1] = atof(argv[++i]);
                                ourview.vup[2] = atof(argv[++i]);
                                break;
                        case 'h':                               /* horizontal */
                                check(3,1);
                                ourview.horiz = atof(argv[++i]);
                                break;
                        case 'v':                               /* vertical */
                                check(3,1);
                                ourview.vert = atof(argv[++i]);
                                break;
                        case 'f':                               /* file */
                                check(3,1);
                                gotvfile = viewfile(argv[++i], &ourview);
                                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:
                                goto badopt;
                        }
                        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);
        }
                                                /* allocate frame */
        ourpict = (COLR *)malloc(ourview.hresolu*ourview.vresolu*sizeof(COLR));
        ourzbuf = (float *)calloc(ourview.hresolu*ourview.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 (ourexp > 0 && ourexp != 1.0)
                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 zthresh][-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, *zfp;
        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(&theirview.hresolu, &theirview.vresolu, 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(theirview.hresolu*sizeof(COLR));
        zin = (float *)malloc(theirview.hresolu*sizeof(float));
        plast = (struct position *)calloc(theirview.hresolu,
                                                sizeof(struct position));
        if (scanin == NULL || zin == NULL || plast == NULL)
                syserror();
                                        /* get z specification or file */
        if ((zfp = fopen(zspec, "r")) == NULL) {
                double  zvalue;
                register int    x;
                if (!isfloat(zspec) || (zvalue = atof(zspec)) <= 0.0) {
                        perror(zspec);
                        exit(1);
                }
                for (x = 0; x < theirview.hresolu; x++)
                        zin[x] = zvalue;
        }
                                        /* load image */
        for (y = theirview.vresolu-1; y >= 0; y--) {
                if (freadcolrs(scanin, theirview.hresolu, pfp) < 0) {
                        fprintf(stderr, "%s: read error\n", pfile);
                        exit(1);
                }
                if (zfp != NULL
                        && fread(zin,sizeof(float),theirview.hresolu,zfp)
                                < theirview.hresolu) {
                        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 (zfp != NULL)
                fclose(zfp);
}


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->vhinc[0];
        xfmat[0][1] = vw1->vhinc[1];
        xfmat[0][2] = vw1->vhinc[2];
        xfmat[1][0] = vw1->vvinc[0];
        xfmat[1][1] = vw1->vvinc[1];
        xfmat[1][2] = vw1->vvinc[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->vhinc[0]/vw2->vhn2;
        m4t[1][0] = vw2->vhinc[1]/vw2->vhn2;
        m4t[2][0] = vw2->vhinc[2]/vw2->vhn2;
        m4t[3][0] = -DOT(vw2->vp,vw2->vhinc)/vw2->vhn2;
        m4t[0][1] = vw2->vvinc[0]/vw2->vvn2;
        m4t[1][1] = vw2->vvinc[1]/vw2->vvn2;
        m4t[2][1] = vw2->vvinc[2]/vw2->vvn2;
        m4t[3][1] = -DOT(vw2->vp,vw2->vvinc)/vw2->vvn2;
        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;

        for (x = theirview.hresolu-1; x >= 0; x--) {
                pos[0] = x - .5*(theirview.hresolu-1);
                pos[1] = y - .5*(theirview.vresolu-1);
                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.vhn2
                                        + pos[1]*pos[1]*theirview.vvn2 );
                        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.hresolu;
                pos[1] += .5*ourview.vresolu;
                newpos.x = pos[0];
                newpos.y = pos[1];
                newpos.z = zline[x];
                                        /* add pixel to our image */
                if (pos[0] >= 0 && newpos.x < ourview.hresolu
                                && pos[1] >= 0 && newpos.y < ourview.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(ourview.hresolu*sizeof(int));
        if (yback == NULL)
                syserror();
        for (x = 0; x < ourview.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 < ourview.vresolu; y++) {
                xback = -2;
                for (x = 0; x < ourview.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 < ourview.vresolu; i++)
                                                if (zscan(i)[x] > 0)
                                                        break;
                                        if (i < ourview.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 < ourview.hresolu; i++)
                                                if (zscan(y)[i] > 0)
                                                        break;
                                        if (i < ourview.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 < ourview.vresolu; y++)
                for (x = 0; x < ourview.hresolu; x++)
                        if (zscan(y)[x] <= 0)
                                (*deffill)(x,y);
}


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

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


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

        if ((fp = fopen(fname, "w")) == NULL) {
                perror(fname);
                exit(1);
        }
        if (donorm
        && (zout = (float *)malloc(ourview.hresolu*sizeof(float))) == NULL)
                syserror();
        for (y = ourview.vresolu-1; y >= 0; y--) {
                if (donorm) {
                        double  vx, yzn2;
                        register int    x;
                        yzn2 = y - .5*(ourview.vresolu-1);
                        yzn2 = 1. + yzn2*yzn2*ourview.vvn2;
                        for (x = 0; x < ourview.hresolu; x++) {
                                vx = x - .5*(ourview.hresolu-1);
                                zout[x] = zscan(y)[x]
                                        * sqrt(vx*vx*ourview.vhn2 + yzn2);
                        }
                } else
                        zout = zscan(y);
                if (fwrite(zout, sizeof(float), ourview.hresolu, fp)
                                < ourview.hresolu) {
                        perror(fname);
                        exit(1);
                }
        }
        if (donorm)
                free((char *)zout);
        fclose(fp);
}


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


rcalfill(x, y)                          /* fill with ray-calculated pixel */
int     x, y;
{
        FVECT   orig, dir;
        float   outbuf[6];

        if (queuesiz >= PACKSIZ) {      /* flush queue */
                if (fflush(psend) == EOF)
                        syserror();
                clearqueue();
        }
                                        /* send new ray */
        rayview(orig, dir, &ourview, x+.5, y+.5);
        outbuf[0] = orig[0]; outbuf[1] = orig[1]; outbuf[2] = orig[2];
        outbuf[3] = dir[0]; outbuf[4] = dir[1]; outbuf[5] = dir[2];
        if (fwrite(outbuf, sizeof(float), 6, psend) < 6)
                syserror();
                                        /* remember it */
        queue[queuesiz][0] = x;
        queue[queuesiz][1] = y;
        queuesiz++;
}


clearqueue()                            /* get results from queue */
{
        float   inbuf[4];
        register int    i;

        for (i = 0; i < queuesiz; i++) {
                if (fread(inbuf, sizeof(float), 4, precv) < 4) {
                        fprintf(stderr, "%s: read error in clearqueue\n",
                                        progname);
                        exit(1);
                }
                if (ourexp > 0 && ourexp != 1.0) {
                        inbuf[0] *= ourexp;
                        inbuf[1] *= ourexp;
                        inbuf[2] *= ourexp;
                }
                setcolr(pscan(queue[i][1])[queue[i][0]],
                                inbuf[0], inbuf[1], inbuf[2]);
                zscan(queue[i][1])[queue[i][0]] = inbuf[3];
        }
        queuesiz = 0;
}


syserror()                      /* report error and exit */
{
        perror(progname);
        exit(1);
}
Revision:	1.16
Committed:	Sat Jan 6 22:27:10 1990 UTC (34 years, 3 months ago) by greg
Content type:	text/plain
Branch:	MAIN
Changes since 1.15:	+23 -6 lines
Log Message:	added code to deal with picture exposure
#	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			#include "view.h"
14
15			#include "color.h"
16
17			#define pscan(y) (ourpict+(y)*ourview.hresolu)
18			#define zscan(y) (ourzbuf+(y)*ourview.hresolu)
19
20	greg	1.13	#define F_FORE 1 /* fill foreground */
21			#define F_BACK 2 /* fill background */
22	greg	1.11
23	greg	1.13	#define PACKSIZ 42 /* calculation packet size */
24
25			#define RTCOM "rtrace -h -ovl -fff -x %d %s"
26
27	greg	1.3	#define ABS(x) ((x)>0?(x):-(x))
28
29	greg	1.15	struct position {int x,y; float z;};
30
31	greg	1.1	VIEW ourview = STDVIEW(512); /* desired view */
32
33	greg	1.8	double zeps = .02; /* allowed z epsilon */
34	greg	1.1
35			COLR ourpict; / output picture */
36			float ourzbuf; / corresponding z-buffer */
37
38			char *progname;
39
40	greg	1.12	int fill = F_FORE\|F_BACK; /* selected fill algorithm */
41	greg	1.14	extern int backfill(), rcalfill(); /* fill functions */
42	greg	1.12	int (deffill)() = backfill; / selected fill function */
43	greg	1.11	COLR backcolr = BLKCOLR; /* background color */
44	greg	1.13	double backz = 0.0; /* background z value */
45	greg	1.16	int normdist = 1; /* normalized distance? */
46			double ourexp = -1; /* output picture exposure */
47	greg	1.11
48	greg	1.16	VIEW theirview = STDVIEW(512); /* input view */
49			int gotview; /* got input view? */
50	greg	1.5	double theirs2ours[4][4]; /* transformation matrix */
51	greg	1.16	double theirexp; /* input picture exposure */
52	greg	1.1
53	greg	1.14	int childpid = -1; /* id of fill process */
54	greg	1.13	FILE psend, precv; /* pipes to/from fill calculation */
55			int queue[PACKSIZ][2]; /* pending pixels */
56			int queuesiz; /* number of pixels pending */
57	greg	1.5
58	greg	1.13
59	greg	1.1	main(argc, argv) /* interpolate pictures */
60			int argc;
61			char *argv[];
62			{
63			#define check(olen,narg) if (argv[i][olen] \|\| narg >= argc-i) goto badopt
64	greg	1.11	extern double atof();
65	greg	1.1	int gotvfile = 0;
66	greg	1.11	char *zfile = NULL;
67	greg	1.1	char *err;
68			int i;
69
70			progname = argv[0];
71
72			for (i = 1; i < argc && argv[i][0] == '-'; i++)
73			switch (argv[i][1]) {
74			case 't': /* threshold */
75			check(2,1);
76			zeps = atof(argv[++i]);
77			break;
78	greg	1.11	case 'n': /* dist. normalized? */
79	greg	1.10	check(2,0);
80	greg	1.11	normdist = !normdist;
81	greg	1.10	break;
82	greg	1.11	case 'f': /* fill type */
83			switch (argv[i][2]) {
84			case '0': /* none */
85			check(3,0);
86			fill = 0;
87			break;
88			case 'f': /* foreground */
89			check(3,0);
90			fill = F_FORE;
91			break;
92			case 'b': /* background */
93			check(3,0);
94			fill = F_BACK;
95			break;
96			case 'a': /* all */
97			check(3,0);
98			fill = F_FORE\|F_BACK;
99			break;
100			case 'c': /* color */
101			check(3,3);
102	greg	1.12	deffill = backfill;
103	greg	1.11	setcolr(backcolr, atof(argv[i+1]),
104			atof(argv[i+2]), atof(argv[i+3]));
105			i += 3;
106			break;
107	greg	1.13	case 'z': /* z value */
108			check(3,1);
109			deffill = backfill;
110			backz = atof(argv[++i]);
111			break;
112			case 'r': /* rtrace */
113			check(3,1);
114	greg	1.14	deffill = rcalfill;
115	greg	1.13	calstart(RTCOM, argv[++i]);
116			break;
117	greg	1.11	default:
118			goto badopt;
119			}
120			break;
121			case 'z': /* z file */
122			check(2,1);
123			zfile = argv[++i];
124			break;
125	greg	1.6	case 'x': /* x resolution */
126			check(2,1);
127			ourview.hresolu = atoi(argv[++i]);
128			break;
129			case 'y': /* y resolution */
130			check(2,1);
131			ourview.vresolu = atoi(argv[++i]);
132			break;
133	greg	1.1	case 'v': /* view */
134			switch (argv[i][2]) {
135			case 't': /* type */
136			check(4,0);
137			ourview.type = argv[i][3];
138			break;
139			case 'p': /* point */
140			check(3,3);
141			ourview.vp[0] = atof(argv[++i]);
142			ourview.vp[1] = atof(argv[++i]);
143			ourview.vp[2] = atof(argv[++i]);
144			break;
145			case 'd': /* direction */
146			check(3,3);
147			ourview.vdir[0] = atof(argv[++i]);
148			ourview.vdir[1] = atof(argv[++i]);
149			ourview.vdir[2] = atof(argv[++i]);
150			break;
151			case 'u': /* up */
152			check(3,3);
153			ourview.vup[0] = atof(argv[++i]);
154			ourview.vup[1] = atof(argv[++i]);
155			ourview.vup[2] = atof(argv[++i]);
156			break;
157			case 'h': /* horizontal */
158			check(3,1);
159			ourview.horiz = atof(argv[++i]);
160			break;
161			case 'v': /* vertical */
162			check(3,1);
163			ourview.vert = atof(argv[++i]);
164			break;
165			case 'f': /* file */
166			check(3,1);
167			gotvfile = viewfile(argv[++i], &ourview);
168			if (gotvfile < 0) {
169			perror(argv[i]);
170			exit(1);
171			} else if (gotvfile == 0) {
172			fprintf(stderr, "%s: bad view file\n",
173			argv[i]);
174			exit(1);
175			}
176			break;
177			default:
178			goto badopt;
179			}
180			break;
181			default:
182			badopt:
183	greg	1.10	fprintf(stderr, "%s: command line error at '%s'\n",
184	greg	1.1	progname, argv[i]);
185	greg	1.10	goto userr;
186	greg	1.1	}
187			/* check arguments */
188	greg	1.13	if ((argc-i)%2)
189	greg	1.10	goto userr;
190	greg	1.1	/* set view */
191			if (err = setview(&ourview)) {
192			fprintf(stderr, "%s: %s\n", progname, err);
193			exit(1);
194			}
195			/* allocate frame */
196	greg	1.12	ourpict = (COLR )malloc(ourview.hresoluourview.vresolu*sizeof(COLR));
197	greg	1.1	ourzbuf = (float )calloc(ourview.hresoluourview.vresolu,sizeof(float));
198	greg	1.15	if (ourpict == NULL \|\| ourzbuf == NULL)
199			syserror();
200	greg	1.1	/* get input */
201			for ( ; i < argc; i += 2)
202			addpicture(argv[i], argv[i+1]);
203			/* fill in spaces */
204	greg	1.11	if (fill&F_BACK)
205	greg	1.12	backpicture();
206			else
207	greg	1.11	fillpicture();
208	greg	1.13	/* close calculation */
209	greg	1.14	caldone();
210	greg	1.1	/* add to header */
211			printargs(argc, argv, stdout);
212			if (gotvfile) {
213			printf(VIEWSTR);
214			fprintview(&ourview, stdout);
215			printf("\n");
216			}
217	greg	1.16	if (ourexp > 0 && ourexp != 1.0)
218			fputexpos(ourexp, stdout);
219	greg	1.1	printf("\n");
220	greg	1.11	/* write picture */
221	greg	1.1	writepicture();
222	greg	1.11	/* write z file */
223			if (zfile != NULL)
224			writedistance(zfile);
225	greg	1.1
226			exit(0);
227	greg	1.10	userr:
228			fprintf(stderr,
229	greg	1.11	"Usage: %s [view opts][-t zthresh][-z zout][-fT][-n] pfile zspec ..\n",
230	greg	1.10	progname);
231			exit(1);
232	greg	1.1	#undef check
233			}
234
235
236			headline(s) /* process header string */
237			char *s;
238			{
239			static char *altname[] = {"rview","rpict","pinterp",VIEWSTR,NULL};
240			register char **an;
241
242			printf("\t%s", s);
243
244	greg	1.16	if (isexpos(s)) {
245			theirexp *= exposval(s);
246			return;
247			}
248	greg	1.1	for (an = altname; *an != NULL; an++)
249			if (!strncmp(an, s, strlen(an))) {
250			if (sscanview(&theirview, s+strlen(*an)) == 0)
251			gotview++;
252			break;
253			}
254			}
255
256
257	greg	1.10	addpicture(pfile, zspec) /* add picture to output */
258			char pfile, zspec;
259	greg	1.1	{
260	greg	1.10	extern double atof();
261	greg	1.1	FILE pfp, zfp;
262	greg	1.8	char *err;
263	greg	1.1	COLR *scanin;
264	greg	1.15	float *zin;
265			struct position *plast;
266	greg	1.1	int y;
267	greg	1.10	/* open picture file */
268	greg	1.1	if ((pfp = fopen(pfile, "r")) == NULL) {
269			perror(pfile);
270			exit(1);
271			}
272	greg	1.16	/* get header with exposure and view */
273			theirexp = 1.0;
274			gotview = 0;
275	greg	1.1	printf("%s:\n", pfile);
276			getheader(pfp, headline);
277	greg	1.9	if (!gotview \|\| fgetresolu(&theirview.hresolu, &theirview.vresolu, pfp)
278			!= (YMAJOR\|YDECR)) {
279	greg	1.1	fprintf(stderr, "%s: picture view error\n", pfile);
280			exit(1);
281			}
282	greg	1.16	if (ourexp <= 0)
283			ourexp = theirexp;
284			else if (ABS(theirexp-ourexp) > .01*ourexp)
285			fprintf(stderr, "%s: different exposure (warning)\n", pfile);
286	greg	1.1	if (err = setview(&theirview)) {
287			fprintf(stderr, "%s: %s\n", pfile, err);
288			exit(1);
289			}
290	greg	1.5	/* compute transformation */
291			pixform(theirs2ours, &theirview, &ourview);
292	greg	1.1	/* allocate scanlines */
293	greg	1.9	scanin = (COLR )malloc(theirview.hresolusizeof(COLR));
294			zin = (float )malloc(theirview.hresolusizeof(float));
295	greg	1.15	plast = (struct position *)calloc(theirview.hresolu,
296			sizeof(struct position));
297			if (scanin == NULL \|\| zin == NULL \|\| plast == NULL)
298			syserror();
299	greg	1.10	/* get z specification or file */
300			if ((zfp = fopen(zspec, "r")) == NULL) {
301			double zvalue;
302			register int x;
303			if (!isfloat(zspec) \|\| (zvalue = atof(zspec)) <= 0.0) {
304			perror(zspec);
305			exit(1);
306			}
307			for (x = 0; x < theirview.hresolu; x++)
308			zin[x] = zvalue;
309			}
310	greg	1.1	/* load image */
311	greg	1.9	for (y = theirview.vresolu-1; y >= 0; y--) {
312			if (freadcolrs(scanin, theirview.hresolu, pfp) < 0) {
313	greg	1.1	fprintf(stderr, "%s: read error\n", pfile);
314			exit(1);
315			}
316	greg	1.10	if (zfp != NULL
317			&& fread(zin,sizeof(float),theirview.hresolu,zfp)
318	greg	1.9	< theirview.hresolu) {
319	greg	1.10	fprintf(stderr, "%s: read error\n", zspec);
320	greg	1.1	exit(1);
321			}
322	greg	1.15	addscanline(y, scanin, zin, plast);
323	greg	1.1	}
324			/* clean up */
325			free((char *)scanin);
326			free((char *)zin);
327	greg	1.9	free((char *)plast);
328	greg	1.1	fclose(pfp);
329	greg	1.10	if (zfp != NULL)
330			fclose(zfp);
331	greg	1.1	}
332
333
334	greg	1.5	pixform(xfmat, vw1, vw2) /* compute view1 to view2 matrix */
335			register double xfmat[4][4];
336			register VIEW vw1, vw2;
337			{
338			double m4t[4][4];
339
340			setident4(xfmat);
341			xfmat[0][0] = vw1->vhinc[0];
342			xfmat[0][1] = vw1->vhinc[1];
343			xfmat[0][2] = vw1->vhinc[2];
344			xfmat[1][0] = vw1->vvinc[0];
345			xfmat[1][1] = vw1->vvinc[1];
346			xfmat[1][2] = vw1->vvinc[2];
347			xfmat[2][0] = vw1->vdir[0];
348			xfmat[2][1] = vw1->vdir[1];
349			xfmat[2][2] = vw1->vdir[2];
350			xfmat[3][0] = vw1->vp[0];
351			xfmat[3][1] = vw1->vp[1];
352			xfmat[3][2] = vw1->vp[2];
353			setident4(m4t);
354			m4t[0][0] = vw2->vhinc[0]/vw2->vhn2;
355			m4t[1][0] = vw2->vhinc[1]/vw2->vhn2;
356			m4t[2][0] = vw2->vhinc[2]/vw2->vhn2;
357			m4t[3][0] = -DOT(vw2->vp,vw2->vhinc)/vw2->vhn2;
358			m4t[0][1] = vw2->vvinc[0]/vw2->vvn2;
359			m4t[1][1] = vw2->vvinc[1]/vw2->vvn2;
360			m4t[2][1] = vw2->vvinc[2]/vw2->vvn2;
361			m4t[3][1] = -DOT(vw2->vp,vw2->vvinc)/vw2->vvn2;
362			m4t[0][2] = vw2->vdir[0];
363			m4t[1][2] = vw2->vdir[1];
364			m4t[2][2] = vw2->vdir[2];
365			m4t[3][2] = -DOT(vw2->vp,vw2->vdir);
366			multmat4(xfmat, xfmat, m4t);
367			}
368
369
370	greg	1.15	addscanline(y, pline, zline, lasty) /* add scanline to output */
371	greg	1.1	int y;
372			COLR *pline;
373			float *zline;
374	greg	1.15	struct position lasty; / input/output */
375	greg	1.1	{
376	greg	1.11	extern double sqrt();
377	greg	1.5	double pos[3];
378	greg	1.15	struct position lastx, newpos;
379	greg	1.1	register int x;
380
381	greg	1.8	for (x = theirview.hresolu-1; x >= 0; x--) {
382	greg	1.5	pos[0] = x - .5*(theirview.hresolu-1);
383			pos[1] = y - .5*(theirview.vresolu-1);
384			pos[2] = zline[x];
385			if (theirview.type == VT_PER) {
386	greg	1.11	if (normdist) /* adjust for eye-ray distance */
387	greg	1.10	pos[2] /= sqrt( 1.
388	greg	1.5	+ pos[0]pos[0]theirview.vhn2
389			+ pos[1]pos[1]theirview.vvn2 );
390			pos[0] *= pos[2];
391			pos[1] *= pos[2];
392			}
393			multp3(pos, pos, theirs2ours);
394	greg	1.15	if (pos[2] <= 0) {
395			lasty[x].z = lastx.z = 0; /* mark invalid */
396	greg	1.1	continue;
397	greg	1.15	}
398	greg	1.5	if (ourview.type == VT_PER) {
399			pos[0] /= pos[2];
400			pos[1] /= pos[2];
401			}
402			pos[0] += .5*ourview.hresolu;
403			pos[1] += .5*ourview.vresolu;
404	greg	1.15	newpos.x = pos[0];
405			newpos.y = pos[1];
406			newpos.z = zline[x];
407	greg	1.8	/* add pixel to our image */
408	greg	1.15	if (pos[0] >= 0 && newpos.x < ourview.hresolu
409			&& pos[1] >= 0 && newpos.y < ourview.vresolu) {
410			addpixel(&newpos, &lastx, &lasty[x], pline[x], pos[2]);
411			lasty[x].x = lastx.x = newpos.x;
412			lasty[x].y = lastx.y = newpos.y;
413			lasty[x].z = lastx.z = newpos.z;
414			} else
415			lasty[x].z = lastx.z = 0; /* mark invalid */
416	greg	1.1	}
417			}
418
419
420	greg	1.15	addpixel(p0, p1, p2, pix, z) /* fill in pixel parallelogram */
421			struct position p0, p1, *p2;
422	greg	1.8	COLR pix;
423			double z;
424			{
425	greg	1.15	double zt = 2.zepsp0->z; /* threshold */
426			int s1x, s1y, s2x, s2y; /* step sizes */
427			int l1, l2, c1, c2; /* side lengths and counters */
428			int p1isy; /* p0p1 along y? */
429			int x1, y1; /* p1 position */
430			register int x, y; /* final position */
431
432			/* compute vector p0p1 */
433			if (fill&F_FORE && ABS(p1->z-p0->z) <= zt) {
434			s1x = p1->x - p0->x;
435			s1y = p1->y - p0->y;
436			l1 = ABS(s1x);
437			if (p1isy = (ABS(s1y) > l1))
438			l1 = ABS(s1y);
439			} else {
440			l1 = s1x = s1y = 1;
441			p1isy = -1;
442			}
443			/* compute vector p0p2 */
444			if (fill&F_FORE && ABS(p2->z-p0->z) <= zt) {
445			s2x = p2->x - p0->x;
446			s2y = p2->y - p0->y;
447			if (p1isy == 1)
448			l2 = ABS(s2x);
449			else {
450			l2 = ABS(s2y);
451			if (p1isy != 0 && ABS(s2x) > l2)
452			l2 = ABS(s2x);
453			}
454			} else
455			l2 = s2x = s2y = 1;
456			/* fill the parallelogram */
457			for (c1 = l1; c1-- > 0; ) {
458			x1 = p0->x + c1*s1x/l1;
459			y1 = p0->y + c1*s1y/l1;
460			for (c2 = l2; c2-- > 0; ) {
461			x = x1 + c2*s2x/l2;
462			y = y1 + c2*s2y/l2;
463			if (zscan(y)[x] <= 0 \|\| zscan(y)[x]-z
464			> zeps*zscan(y)[x]) {
465	greg	1.8	zscan(y)[x] = z;
466			copycolr(pscan(y)[x], pix);
467			}
468	greg	1.15	}
469			}
470	greg	1.8	}
471
472
473	greg	1.12	backpicture() /* background fill algorithm */
474	greg	1.1	{
475	greg	1.2	int *yback, xback;
476	greg	1.1	int y;
477	greg	1.2	COLR pfill;
478			register int x, i;
479			/* get back buffer */
480			yback = (int )malloc(ourview.hresolusizeof(int));
481	greg	1.15	if (yback == NULL)
482			syserror();
483	greg	1.2	for (x = 0; x < ourview.hresolu; x++)
484	greg	1.4	yback[x] = -2;
485	greg	1.7	/*
486			* Xback and yback are the pixel locations of suitable
487			* background values in each direction.
488			* A value of -2 means unassigned, and -1 means
489			* that there is no suitable background in this direction.
490			*/
491	greg	1.2	/* fill image */
492	greg	1.4	for (y = 0; y < ourview.vresolu; y++) {
493			xback = -2;
494	greg	1.1	for (x = 0; x < ourview.hresolu; x++)
495	greg	1.8	if (zscan(y)[x] <= 0) { /* empty pixel */
496	greg	1.7	/*
497			* First, find background from above or below.
498			* (farthest assigned pixel)
499			*/
500	greg	1.4	if (yback[x] == -2) {
501			for (i = y+1; i < ourview.vresolu; i++)
502	greg	1.8	if (zscan(i)[x] > 0)
503	greg	1.4	break;
504			if (i < ourview.vresolu
505	greg	1.2	&& (y <= 0 \|\| zscan(y-1)[x] < zscan(i)[x]))
506	greg	1.4	yback[x] = i;
507			else
508			yback[x] = y-1;
509	greg	1.2	}
510	greg	1.7	/*
511			* Next, find background from left or right.
512			*/
513	greg	1.4	if (xback == -2) {
514	greg	1.11	for (i = x+1; i < ourview.hresolu; i++)
515	greg	1.8	if (zscan(y)[i] > 0)
516	greg	1.4	break;
517			if (i < ourview.hresolu
518			&& (x <= 0 \|\| zscan(y)[x-1] < zscan(y)[i]))
519			xback = i;
520			else
521			xback = x-1;
522			}
523	greg	1.7	/*
524	greg	1.11	* Check to see if we have no background for
525			* this pixel. If not, use background color.
526			*/
527			if (xback < 0 && yback[x] < 0) {
528	greg	1.12	(*deffill)(x,y);
529	greg	1.11	continue;
530			}
531			/*
532	greg	1.7	* Compare, and use the background that is
533			* farther, unless one of them is next to us.
534			*/
535	greg	1.11	if ( yback[x] < 0
536			\|\| (xback >= 0 && ABS(x-xback) <= 1)
537	greg	1.4	\|\| ( ABS(y-yback[x]) > 1
538	greg	1.11	&& zscan(yback[x])[x]
539	greg	1.13	< zscan(y)[xback] ) ) {
540	greg	1.4	copycolr(pscan(y)[x],pscan(y)[xback]);
541	greg	1.13	zscan(y)[x] = zscan(y)[xback];
542			} else {
543	greg	1.4	copycolr(pscan(y)[x],pscan(yback[x])[x]);
544	greg	1.13	zscan(y)[x] = zscan(yback[x])[x];
545			}
546	greg	1.4	} else { /* full pixel */
547			yback[x] = -2;
548			xback = -2;
549			}
550			}
551	greg	1.2	free((char *)yback);
552	greg	1.1	}
553
554
555	greg	1.12	fillpicture() /* paint in empty pixels with default */
556	greg	1.11	{
557			register int x, y;
558
559			for (y = 0; y < ourview.vresolu; y++)
560			for (x = 0; x < ourview.hresolu; x++)
561			if (zscan(y)[x] <= 0)
562	greg	1.12	(*deffill)(x,y);
563	greg	1.11	}
564
565
566	greg	1.1	writepicture() /* write out picture */
567			{
568			int y;
569
570			fputresolu(YMAJOR\|YDECR, ourview.hresolu, ourview.vresolu, stdout);
571			for (y = ourview.vresolu-1; y >= 0; y--)
572	greg	1.15	if (fwritecolrs(pscan(y), ourview.hresolu, stdout) < 0)
573			syserror();
574	greg	1.11	}
575
576
577			writedistance(fname) /* write out z file */
578			char *fname;
579			{
580			extern double sqrt();
581			int donorm = normdist && ourview.type == VT_PER;
582			FILE *fp;
583			int y;
584			float *zout;
585
586			if ((fp = fopen(fname, "w")) == NULL) {
587			perror(fname);
588			exit(1);
589			}
590			if (donorm
591	greg	1.15	&& (zout = (float )malloc(ourview.hresolusizeof(float))) == NULL)
592			syserror();
593	greg	1.11	for (y = ourview.vresolu-1; y >= 0; y--) {
594			if (donorm) {
595			double vx, yzn2;
596			register int x;
597			yzn2 = y - .5*(ourview.vresolu-1);
598			yzn2 = 1. + yzn2yzn2ourview.vvn2;
599			for (x = 0; x < ourview.hresolu; x++) {
600			vx = x - .5*(ourview.hresolu-1);
601			zout[x] = zscan(y)[x]
602			* sqrt(vxvxourview.vhn2 + yzn2);
603			}
604			} else
605			zout = zscan(y);
606			if (fwrite(zout, sizeof(float), ourview.hresolu, fp)
607			< ourview.hresolu) {
608			perror(fname);
609			exit(1);
610			}
611			}
612			if (donorm)
613			free((char *)zout);
614			fclose(fp);
615	greg	1.10	}
616
617
618			isfloat(s) /* see if string is floating number */
619			register char *s;
620			{
621			for ( ; *s; s++)
622			if ((s < '0' \|\| s > '9') && s != '.' && s != '-'
623			&& s != 'e' && s != 'E' && *s != '+')
624			return(0);
625			return(1);
626	greg	1.12	}
627
628
629			backfill(x, y) /* fill pixel with background */
630			int x, y;
631			{
632			register BYTE *dest = pscan(y)[x];
633
634			copycolr(dest, backcolr);
635	greg	1.13	zscan(y)[x] = backz;
636			}
637
638
639			calstart(prog, args) /* start fill calculation */
640			char prog, args;
641			{
642			char combuf[512];
643			int p0[2], p1[2];
644
645	greg	1.14	if (childpid != -1) {
646			fprintf(stderr, "%s: too many calculations\n", progname);
647			exit(1);
648			}
649	greg	1.13	sprintf(combuf, prog, PACKSIZ, args);
650			if (pipe(p0) < 0 \|\| pipe(p1) < 0)
651	greg	1.14	syserror();
652	greg	1.13	if ((childpid = vfork()) == 0) { /* fork calculation */
653			close(p0[1]);
654			close(p1[0]);
655			if (p0[0] != 0) {
656			dup2(p0[0], 0);
657			close(p0[0]);
658			}
659			if (p1[1] != 1) {
660			dup2(p1[1], 1);
661			close(p1[1]);
662			}
663			execl("/bin/sh", "sh", "-c", combuf, 0);
664			perror("/bin/sh");
665			_exit(127);
666			}
667	greg	1.14	if (childpid == -1)
668			syserror();
669	greg	1.13	close(p0[0]);
670			close(p1[1]);
671			if ((psend = fdopen(p0[1], "w")) == NULL)
672	greg	1.14	syserror();
673	greg	1.13	if ((precv = fdopen(p1[0], "r")) == NULL)
674	greg	1.14	syserror();
675	greg	1.13	queuesiz = 0;
676			}
677
678
679			caldone() /* done with calculation */
680			{
681			int pid;
682
683	greg	1.14	if (childpid == -1)
684			return;
685			if (fclose(psend) == EOF)
686			syserror();
687	greg	1.13	clearqueue();
688			fclose(precv);
689			while ((pid = wait(0)) != -1 && pid != childpid)
690			;
691	greg	1.14	childpid = -1;
692	greg	1.13	}
693
694
695	greg	1.14	rcalfill(x, y) /* fill with ray-calculated pixel */
696	greg	1.13	int x, y;
697			{
698			FVECT orig, dir;
699			float outbuf[6];
700
701			if (queuesiz >= PACKSIZ) { /* flush queue */
702	greg	1.14	if (fflush(psend) == EOF)
703			syserror();
704	greg	1.13	clearqueue();
705			}
706			/* send new ray */
707			rayview(orig, dir, &ourview, x+.5, y+.5);
708			outbuf[0] = orig[0]; outbuf[1] = orig[1]; outbuf[2] = orig[2];
709			outbuf[3] = dir[0]; outbuf[4] = dir[1]; outbuf[5] = dir[2];
710	greg	1.14	if (fwrite(outbuf, sizeof(float), 6, psend) < 6)
711			syserror();
712	greg	1.13	/* remember it */
713			queue[queuesiz][0] = x;
714			queue[queuesiz][1] = y;
715			queuesiz++;
716			}
717
718
719			clearqueue() /* get results from queue */
720			{
721			float inbuf[4];
722			register int i;
723
724			for (i = 0; i < queuesiz; i++) {
725	greg	1.14	if (fread(inbuf, sizeof(float), 4, precv) < 4) {
726			fprintf(stderr, "%s: read error in clearqueue\n",
727			progname);
728			exit(1);
729	greg	1.16	}
730			if (ourexp > 0 && ourexp != 1.0) {
731			inbuf[0] *= ourexp;
732			inbuf[1] *= ourexp;
733			inbuf[2] *= ourexp;
734	greg	1.14	}
735	greg	1.13	setcolr(pscan(queue[i][1])[queue[i][0]],
736			inbuf[0], inbuf[1], inbuf[2]);
737			zscan(queue[i][1])[queue[i][0]] = inbuf[3];
738			}
739			queuesiz = 0;
740	greg	1.14	}
741
742
743			syserror() /* report error and exit */
744			{
745			perror(progname);
746			exit(1);
747	greg	1.1	}