src/common/image.c

#ifndef lint
static const char       RCSid[] = "$Id: image.c,v 2.33 2006/11/19 01:14:31 greg Exp $";
#endif
/*
 *  image.c - routines for image generation.
 *
 *  External symbols declared in view.h
 */

#include "copyright.h"

#include  <ctype.h>
#include  "rtio.h"
#include  "rtmath.h"
#include  "paths.h"
#include  "view.h"


#define  FEQ(x,y)       (fabs((x)-(y)) <= FTINY)
#define  VEQ(v,w)       (FEQ((v)[0],(w)[0]) && FEQ((v)[1],(w)[1]) \
                                && FEQ((v)[2],(w)[2]))

VIEW  stdview = STDVIEW;                /* default view parameters */

static gethfunc gethview;


char *
setview(v)              /* set hvec and vvec, return message on error */
register VIEW  *v;
{
        static char  ill_horiz[] = "illegal horizontal view size";
        static char  ill_vert[] = "illegal vertical view size";
        
        if (v->vaft < -FTINY || (v->vaft > FTINY && v->vaft <= v->vfore))
                return("illegal fore/aft clipping plane");

        if (v->vdist <= FTINY)
                return("illegal view distance");
        v->vdist *= normalize(v->vdir);         /* normalize direction */
        if (v->vdist == 0.0)
                return("zero view direction");

        if (normalize(v->vup) == 0.0)           /* normalize view up */
                return("zero view up vector");

        fcross(v->hvec, v->vdir, v->vup);       /* compute horiz dir */

        if (normalize(v->hvec) == 0.0)
                return("view up parallel to view direction");

        fcross(v->vvec, v->hvec, v->vdir);      /* compute vert dir */

        if (v->horiz <= FTINY)
                return(ill_horiz);
        if (v->vert <= FTINY)
                return(ill_vert);

        switch (v->type) {
        case VT_PAR:                            /* parallel view */
                v->hn2 = v->horiz;
                v->vn2 = v->vert;
                break;
        case VT_PER:                            /* perspective view */
                if (v->horiz >= 180.0-FTINY)
                        return(ill_horiz);
                if (v->vert >= 180.0-FTINY)
                        return(ill_vert);
                v->hn2 = 2.0 * tan(v->horiz*(PI/180.0/2.0));
                v->vn2 = 2.0 * tan(v->vert*(PI/180.0/2.0));
                break;
        case VT_CYL:                            /* cylindrical panorama */
                if (v->horiz > 360.0+FTINY)
                        return(ill_horiz);
                if (v->vert >= 180.0-FTINY)
                        return(ill_vert);
                v->hn2 = v->horiz * (PI/180.0);
                v->vn2 = 2.0 * tan(v->vert*(PI/180.0/2.0));
                break;
        case VT_ANG:                            /* angular fisheye */
                if (v->horiz > 360.0+FTINY)
                        return(ill_horiz);
                if (v->vert > 360.0+FTINY)
                        return(ill_vert);
                v->hn2 = v->horiz * (PI/180.0);
                v->vn2 = v->vert * (PI/180.0);
                break;
        case VT_HEM:                            /* hemispherical fisheye */
                if (v->horiz > 180.0+FTINY)
                        return(ill_horiz);
                if (v->vert > 180.0+FTINY)
                        return(ill_vert);
                v->hn2 = 2.0 * sin(v->horiz*(PI/180.0/2.0));
                v->vn2 = 2.0 * sin(v->vert*(PI/180.0/2.0));
                break;
        case VT_PLS:                            /* planispheric fisheye */
                if (v->horiz >= 360.0-FTINY)
                        return(ill_horiz);
                if (v->vert >= 360.0-FTINY)
                        return(ill_vert);
                v->hn2 = 2.*sin(v->horiz*(PI/180.0/2.0)) /
                                (1.0 + cos(v->horiz*(PI/180.0/2.0)));
                v->vn2 = 2.*sin(v->vert*(PI/180.0/2.0)) /
                                (1.0 + cos(v->vert*(PI/180.0/2.0)));
                break;
        default:
                return("unknown view type");
        }
        if (v->type != VT_ANG && v->type != VT_PLS) {
                if (v->type != VT_CYL) {
                        v->hvec[0] *= v->hn2;
                        v->hvec[1] *= v->hn2;
                        v->hvec[2] *= v->hn2;
                }
                v->vvec[0] *= v->vn2;
                v->vvec[1] *= v->vn2;
                v->vvec[2] *= v->vn2;
        }
        v->hn2 *= v->hn2;
        v->vn2 *= v->vn2;

        return(NULL);
}


void
normaspect(va, ap, xp, yp)              /* fix pixel aspect or resolution */
double  va;                     /* view aspect ratio */
double  *ap;                    /* pixel aspect in (or out if 0) */
int  *xp, *yp;                  /* x and y resolution in (or out if *ap!=0) */
{
        if (*ap <= FTINY)
                *ap = va * *xp / *yp;           /* compute pixel aspect */
        else if (va * *xp > *ap * *yp)
                *xp = *yp / va * *ap + .5;      /* reduce x resolution */
        else
                *yp = *xp * va / *ap + .5;      /* reduce y resolution */
}


double
viewray(orig, direc, v, x, y)           /* compute ray origin and direction */
FVECT  orig, direc;
register VIEW  *v;
double  x, y;
{
        double  d, z;
        
        x += v->hoff - 0.5;
        y += v->voff - 0.5;

        switch(v->type) {
        case VT_PAR:                    /* parallel view */
                orig[0] = v->vp[0] + v->vfore*v->vdir[0]
                                + x*v->hvec[0] + y*v->vvec[0];
                orig[1] = v->vp[1] + v->vfore*v->vdir[1]
                                + x*v->hvec[1] + y*v->vvec[1];
                orig[2] = v->vp[2] + v->vfore*v->vdir[2]
                                + x*v->hvec[2] + y*v->vvec[2];
                VCOPY(direc, v->vdir);
                return(v->vaft > FTINY ? v->vaft - v->vfore : 0.0);
        case VT_PER:                    /* perspective view */
                direc[0] = v->vdir[0] + x*v->hvec[0] + y*v->vvec[0];
                direc[1] = v->vdir[1] + x*v->hvec[1] + y*v->vvec[1];
                direc[2] = v->vdir[2] + x*v->hvec[2] + y*v->vvec[2];
                orig[0] = v->vp[0] + v->vfore*direc[0];
                orig[1] = v->vp[1] + v->vfore*direc[1];
                orig[2] = v->vp[2] + v->vfore*direc[2];
                d = normalize(direc);
                return(v->vaft > FTINY ? (v->vaft - v->vfore)*d : 0.0);
        case VT_HEM:                    /* hemispherical fisheye */
                z = 1.0 - x*x*v->hn2 - y*y*v->vn2;
                if (z < 0.0)
                        return(-1.0);
                z = sqrt(z);
                direc[0] = z*v->vdir[0] + x*v->hvec[0] + y*v->vvec[0];
                direc[1] = z*v->vdir[1] + x*v->hvec[1] + y*v->vvec[1];
                direc[2] = z*v->vdir[2] + x*v->hvec[2] + y*v->vvec[2];
                orig[0] = v->vp[0] + v->vfore*direc[0];
                orig[1] = v->vp[1] + v->vfore*direc[1];
                orig[2] = v->vp[2] + v->vfore*direc[2];
                return(v->vaft > FTINY ? v->vaft - v->vfore : 0.0);
        case VT_CYL:                    /* cylindrical panorama */
                d = x * v->horiz * (PI/180.0);
                z = cos(d);
                x = sin(d);
                direc[0] = z*v->vdir[0] + x*v->hvec[0] + y*v->vvec[0];
                direc[1] = z*v->vdir[1] + x*v->hvec[1] + y*v->vvec[1];
                direc[2] = z*v->vdir[2] + x*v->hvec[2] + y*v->vvec[2];
                orig[0] = v->vp[0] + v->vfore*direc[0];
                orig[1] = v->vp[1] + v->vfore*direc[1];
                orig[2] = v->vp[2] + v->vfore*direc[2];
                d = normalize(direc);
                return(v->vaft > FTINY ? (v->vaft - v->vfore)*d : 0.0);
        case VT_ANG:                    /* angular fisheye */
                x *= (1.0/180.0)*v->horiz;
                y *= (1.0/180.0)*v->vert;
                d = x*x + y*y;
                if (d > 1.0)
                        return(-1.0);
                d = sqrt(d);
                z = cos(PI*d);
                d = d <= FTINY ? PI : sqrt(1.0 - z*z)/d;
                x *= d;
                y *= d;
                direc[0] = z*v->vdir[0] + x*v->hvec[0] + y*v->vvec[0];
                direc[1] = z*v->vdir[1] + x*v->hvec[1] + y*v->vvec[1];
                direc[2] = z*v->vdir[2] + x*v->hvec[2] + y*v->vvec[2];
                orig[0] = v->vp[0] + v->vfore*direc[0];
                orig[1] = v->vp[1] + v->vfore*direc[1];
                orig[2] = v->vp[2] + v->vfore*direc[2];
                return(v->vaft > FTINY ? v->vaft - v->vfore : 0.0);
        case VT_PLS:                    /* planispheric fisheye */
                x *= sqrt(v->hn2);
                y *= sqrt(v->vn2);
                d = x*x + y*y;
                z = (1. - d)/(1. + d);
                d = d <= FTINY*FTINY ? PI : sqrt((1.0 - z*z)/d);
                x *= d;
                y *= d;
                direc[0] = z*v->vdir[0] + x*v->hvec[0] + y*v->vvec[0];
                direc[1] = z*v->vdir[1] + x*v->hvec[1] + y*v->vvec[1];
                direc[2] = z*v->vdir[2] + x*v->hvec[2] + y*v->vvec[2];
                orig[0] = v->vp[0] + v->vfore*direc[0];
                orig[1] = v->vp[1] + v->vfore*direc[1];
                orig[2] = v->vp[2] + v->vfore*direc[2];
                return(v->vaft > FTINY ? v->vaft - v->vfore : 0.0);
        }
        return(-1.0);
}


void
viewloc(ip, v, p)               /* find image location for point */
FVECT  ip;
register VIEW  *v;
FVECT  p;
{
        double  d, d2;
        FVECT  disp;

        VSUB(disp, p, v->vp);

        switch (v->type) {
        case VT_PAR:                    /* parallel view */
                ip[2] = DOT(disp,v->vdir) - v->vfore;
                break;
        case VT_PER:                    /* perspective view */
                d = DOT(disp,v->vdir);
                ip[2] = VLEN(disp);
                if (d < 0.0) {          /* fold pyramid */
                        ip[2] = -ip[2];
                        d = -d;
                }
                if (d > FTINY) {
                        d = 1.0/d;
                        disp[0] *= d;
                        disp[1] *= d;
                        disp[2] *= d;
                }
                ip[2] *= (1.0 - v->vfore*d);
                break;
        case VT_HEM:                    /* hemispherical fisheye */
                d = normalize(disp);
                if (DOT(disp,v->vdir) < 0.0)
                        ip[2] = -d;
                else
                        ip[2] = d;
                ip[2] -= v->vfore;
                break;
        case VT_CYL:                    /* cylindrical panorama */
                d = DOT(disp,v->hvec);
                d2 = DOT(disp,v->vdir);
                ip[0] = 180.0/PI * atan2(d,d2) / v->horiz + 0.5 - v->hoff;
                d = 1.0/sqrt(d*d + d2*d2);
                ip[1] = DOT(disp,v->vvec)*d/v->vn2 + 0.5 - v->voff;
                ip[2] = VLEN(disp);
                ip[2] *= (1.0 - v->vfore*d);
                return;
        case VT_ANG:                    /* angular fisheye */
                ip[0] = 0.5 - v->hoff;
                ip[1] = 0.5 - v->voff;
                ip[2] = normalize(disp) - v->vfore;
                d = DOT(disp,v->vdir);
                if (d >= 1.0-FTINY)
                        return;
                if (d <= -(1.0-FTINY)) {
                        ip[0] += 180.0/v->horiz;
                        return;
                }
                d = (180.0/PI)*acos(d) / sqrt(1.0 - d*d);
                ip[0] += DOT(disp,v->hvec)*d/v->horiz;
                ip[1] += DOT(disp,v->vvec)*d/v->vert;
                return;
        case VT_PLS:                    /* planispheric fisheye */
                ip[0] = 0.5 - v->hoff;
                ip[1] = 0.5 - v->voff;
                ip[2] = normalize(disp) - v->vfore;
                d = DOT(disp,v->vdir);
                if (d >= 1.0-FTINY)
                        return;
                if (d <= -(1.0-FTINY))
                        return;         /* really an error */
                d = sqrt(1.0 - d*d) / (1.0 + d);
                ip[0] += DOT(disp,v->hvec)*d/sqrt(v->hn2);
                ip[1] += DOT(disp,v->vvec)*d/sqrt(v->vn2);
                return;
        }
        ip[0] = DOT(disp,v->hvec)/v->hn2 + 0.5 - v->hoff;
        ip[1] = DOT(disp,v->vvec)/v->vn2 + 0.5 - v->voff;
}


void
pix2loc(loc, rp, px, py)        /* compute image location from pixel pos. */
RREAL  loc[2];
register RESOLU  *rp;
int  px, py;
{
        register int  x, y;

        if (rp->rt & YMAJOR) {
                x = px;
                y = py;
        } else {
                x = py;
                y = px;
        }
        if (rp->rt & XDECR)
                x = rp->xr-1 - x;
        if (rp->rt & YDECR)
                y = rp->yr-1 - y;
        loc[0] = (x+.5)/rp->xr;
        loc[1] = (y+.5)/rp->yr;
}


void
loc2pix(pp, rp, lx, ly)         /* compute pixel pos. from image location */
int  pp[2];
register RESOLU  *rp;
double  lx, ly;
{
        register int  x, y;

        x = lx * rp->xr;
        y = ly * rp->yr;
        if (rp->rt & XDECR)
                x = rp->xr-1 - x;
        if (rp->rt & YDECR)
                y = rp->yr-1 - y;
        if (rp->rt & YMAJOR) {
                pp[0] = x;
                pp[1] = y;
        } else {
                pp[0] = y;
                pp[1] = x;
        }
}


int
getviewopt(v, ac, av)                   /* process view argument */
register VIEW  *v;
int  ac;
register char  *av[];
{
#define check(c,l)      if ((av[0][c]&&av[0][c]!=' ') || \
                        badarg(ac-1,av+1,l)) return(-1)

        if (ac <= 0 || av[0][0] != '-' || av[0][1] != 'v')
                return(-1);
        switch (av[0][2]) {
        case 't':                       /* type */
                if (!av[0][3] || av[0][3]==' ')
                        return(-1);
                check(4,"");
                v->type = av[0][3];
                return(0);
        case 'p':                       /* point */
                check(3,"fff");
                v->vp[0] = atof(av[1]);
                v->vp[1] = atof(av[2]);
                v->vp[2] = atof(av[3]);
                return(3);
        case 'd':                       /* direction */
                check(3,"fff");
                v->vdir[0] = atof(av[1]);
                v->vdir[1] = atof(av[2]);
                v->vdir[2] = atof(av[3]);
                v->vdist = 1.;
                return(3);
        case 'u':                       /* up */
                check(3,"fff");
                v->vup[0] = atof(av[1]);
                v->vup[1] = atof(av[2]);
                v->vup[2] = atof(av[3]);
                return(3);
        case 'h':                       /* horizontal size */
                check(3,"f");
                v->horiz = atof(av[1]);
                return(1);
        case 'v':                       /* vertical size */
                check(3,"f");
                v->vert = atof(av[1]);
                return(1);
        case 'o':                       /* fore clipping plane */
                check(3,"f");
                v->vfore = atof(av[1]);
                return(1);
        case 'a':                       /* aft clipping plane */
                check(3,"f");
                v->vaft = atof(av[1]);
                return(1);
        case 's':                       /* shift */
                check(3,"f");
                v->hoff = atof(av[1]);
                return(1);
        case 'l':                       /* lift */
                check(3,"f");
                v->voff = atof(av[1]);
                return(1);
        default:
                return(-1);
        }
#undef check
}


int
sscanview(vp, s)                        /* get view parameters from string */
VIEW  *vp;
register char  *s;
{
        int  ac;
        char  *av[4];
        int  na;
        int  nvopts = 0;

        while (isspace(*s))
                if (!*s++)
                        return(0);
        while (*s) {
                ac = 0;
                do {
                        if (ac || *s == '-')
                                av[ac++] = s;
                        while (*s && !isspace(*s))
                                s++;
                        while (isspace(*s))
                                s++;
                } while (*s && ac < 4);
                if ((na = getviewopt(vp, ac, av)) >= 0) {
                        if (na+1 < ac)
                                s = av[na+1];
                        nvopts++;
                } else if (ac > 1)
                        s = av[1];
        }
        return(nvopts);
}


void
fprintview(vp, fp)                      /* write out view parameters */
register VIEW  *vp;
FILE  *fp;
{
        fprintf(fp, " -vt%c", vp->type);
        fprintf(fp, " -vp %.6g %.6g %.6g", vp->vp[0], vp->vp[1], vp->vp[2]);
        fprintf(fp, " -vd %.6g %.6g %.6g", vp->vdir[0]*vp->vdist,
                                                vp->vdir[1]*vp->vdist,
                                                vp->vdir[2]*vp->vdist);
        fprintf(fp, " -vu %.6g %.6g %.6g", vp->vup[0], vp->vup[1], vp->vup[2]);
        fprintf(fp, " -vh %.6g -vv %.6g", vp->horiz, vp->vert);
        fprintf(fp, " -vo %.6g -va %.6g", vp->vfore, vp->vaft);
        fprintf(fp, " -vs %.6g -vl %.6g", vp->hoff, vp->voff);
}


char *
viewopt(vp)                             /* translate to minimal view string */
register VIEW  *vp;
{
        static char  vwstr[128];
        register char  *cp = vwstr;

        *cp = '\0';
        if (vp->type != stdview.type) {
                sprintf(cp, " -vt%c", vp->type);
                cp += strlen(cp);
        }
        if (!VEQ(vp->vp,stdview.vp)) {
                sprintf(cp, " -vp %.6g %.6g %.6g",
                                vp->vp[0], vp->vp[1], vp->vp[2]);
                cp += strlen(cp);
        }
        if (!FEQ(vp->vdist,stdview.vdist) || !VEQ(vp->vdir,stdview.vdir)) {
                sprintf(cp, " -vd %.6g %.6g %.6g",
                                vp->vdir[0]*vp->vdist,
                                vp->vdir[1]*vp->vdist,
                                vp->vdir[2]*vp->vdist);
                cp += strlen(cp);
        }
        if (!VEQ(vp->vup,stdview.vup)) {
                sprintf(cp, " -vu %.6g %.6g %.6g",
                                vp->vup[0], vp->vup[1], vp->vup[2]);
                cp += strlen(cp);
        }
        if (!FEQ(vp->horiz,stdview.horiz)) {
                sprintf(cp, " -vh %.6g", vp->horiz);
                cp += strlen(cp);
        }
        if (!FEQ(vp->vert,stdview.vert)) {
                sprintf(cp, " -vv %.6g", vp->vert);
                cp += strlen(cp);
        }
        if (!FEQ(vp->vfore,stdview.vfore)) {
                sprintf(cp, " -vo %.6g", vp->vfore);
                cp += strlen(cp);
        }
        if (!FEQ(vp->vaft,stdview.vaft)) {
                sprintf(cp, " -va %.6g", vp->vaft);
                cp += strlen(cp);
        }
        if (!FEQ(vp->hoff,stdview.hoff)) {
                sprintf(cp, " -vs %.6g", vp->hoff);
                cp += strlen(cp);
        }
        if (!FEQ(vp->voff,stdview.voff)) {
                sprintf(cp, " -vl %.6g", vp->voff);
                cp += strlen(cp);
        }
        return(vwstr);
}


int
isview(s)                               /* is this a view string? */
char  *s;
{
        static char  *altname[]={NULL,VIEWSTR,"rpict","rview","rvu","rpiece","pinterp",NULL};
        extern char  *progname;
        register char  *cp;
        register char  **an;
                                        /* add program name to list */
        if (altname[0] == NULL) {
                for (cp = progname; *cp; cp++)
                        ;
                while (cp > progname && !ISDIRSEP(cp[-1]))
                        cp--;
                altname[0] = cp;
        }
                                        /* skip leading path */
        cp = s;
        while (*cp && *cp != ' ')
                cp++;
        while (cp > s && !ISDIRSEP(cp[-1]))
                cp--;
        for (an = altname; *an != NULL; an++)
                if (!strncmp(*an, cp, strlen(*an)))
                        return(1);
        return(0);
}


struct myview {
        VIEW    *hv;
        int     ok;
};


static int
gethview(                               /* get view from header */
        char  *s,
        void  *v
)
{
        if (isview(s) && sscanview(((struct myview*)v)->hv, s) > 0)
                ((struct myview*)v)->ok++;
        return(0);
}


int
viewfile(fname, vp, rp)                 /* get view from file */
char  *fname;
VIEW  *vp;
RESOLU  *rp;
{
        struct myview   mvs;
        FILE  *fp;

        if (fname == NULL || !strcmp(fname, "-"))
                fp = stdin;
        else if ((fp = fopen(fname, "r")) == NULL)
                return(-1);

        mvs.hv = vp;
        mvs.ok = 0;

        getheader(fp, gethview, &mvs);

        if (rp != NULL && !fgetsresolu(rp, fp))
                mvs.ok = 0;

        fclose(fp);

        return(mvs.ok);
}
Revision:	2.34
Committed:	Tue Mar 11 02:21:46 2008 UTC (16 years, 1 month ago) by greg
Content type:	text/plain
Branch:	MAIN
CVS Tags:	rad3R9
Changes since 2.33:	+47 -11 lines
Log Message:	Added planisphere view type (-vts option) as requested by Axel Jacobs
#	User	Rev	Content
1	greg	1.1	#ifndef lint
2	greg	2.34	static const char RCSid[] = "$Id: image.c,v 2.33 2006/11/19 01:14:31 greg Exp $";
3	greg	1.1	#endif
4			/*
5			* image.c - routines for image generation.
6	greg	2.16	*
7			* External symbols declared in view.h
8			*/
9
10	greg	2.17	#include "copyright.h"
11	greg	1.1
12	greg	2.32	#include <ctype.h>
13	schorsch	2.22	#include "rtio.h"
14	greg	2.28	#include "rtmath.h"
15	greg	2.27	#include "paths.h"
16	greg	1.1	#include "view.h"
17
18	greg	2.4
19	greg	2.11	#define FEQ(x,y) (fabs((x)-(y)) <= FTINY)
20			#define VEQ(v,w) (FEQ((v)[0],(w)[0]) && FEQ((v)[1],(w)[1]) \
21			&& FEQ((v)[2],(w)[2]))
22
23	greg	1.5	VIEW stdview = STDVIEW; /* default view parameters */
24	greg	1.1
25	schorsch	2.26	static gethfunc gethview;
26
27	greg	1.1
28			char *
29	greg	1.5	setview(v) /* set hvec and vvec, return message on error */
30			register VIEW *v;
31	greg	1.3	{
32	greg	1.12	static char ill_horiz[] = "illegal horizontal view size";
33			static char ill_vert[] = "illegal vertical view size";
34
35	gwlarson	2.15	if (v->vaft < -FTINY \|\| (v->vaft > FTINY && v->vaft <= v->vfore))
36	greg	2.7	return("illegal fore/aft clipping plane");
37
38	greg	2.31	if (v->vdist <= FTINY)
39			return("illegal view distance");
40	greg	2.29	v->vdist = normalize(v->vdir); / normalize direction */
41			if (v->vdist == 0.0)
42	greg	1.1	return("zero view direction");
43
44	greg	1.14	if (normalize(v->vup) == 0.0) /* normalize view up */
45			return("zero view up vector");
46
47	greg	1.5	fcross(v->hvec, v->vdir, v->vup); /* compute horiz dir */
48
49			if (normalize(v->hvec) == 0.0)
50	greg	1.14	return("view up parallel to view direction");
51	greg	1.1
52	greg	1.5	fcross(v->vvec, v->hvec, v->vdir); /* compute vert dir */
53
54	greg	1.12	if (v->horiz <= FTINY)
55			return(ill_horiz);
56			if (v->vert <= FTINY)
57			return(ill_vert);
58
59			switch (v->type) {
60			case VT_PAR: /* parallel view */
61	greg	1.5	v->hn2 = v->horiz;
62	greg	1.12	v->vn2 = v->vert;
63			break;
64			case VT_PER: /* perspective view */
65			if (v->horiz >= 180.0-FTINY)
66			return(ill_horiz);
67			if (v->vert >= 180.0-FTINY)
68			return(ill_vert);
69	greg	1.5	v->hn2 = 2.0 * tan(v->horiz*(PI/180.0/2.0));
70	greg	1.12	v->vn2 = 2.0 * tan(v->vert*(PI/180.0/2.0));
71			break;
72	greg	2.9	case VT_CYL: /* cylindrical panorama */
73			if (v->horiz > 360.0+FTINY)
74			return(ill_horiz);
75			if (v->vert >= 180.0-FTINY)
76			return(ill_vert);
77			v->hn2 = v->horiz * (PI/180.0);
78			v->vn2 = 2.0 * tan(v->vert*(PI/180.0/2.0));
79			break;
80	greg	1.12	case VT_ANG: /* angular fisheye */
81			if (v->horiz > 360.0+FTINY)
82			return(ill_horiz);
83			if (v->vert > 360.0+FTINY)
84			return(ill_vert);
85	greg	2.9	v->hn2 = v->horiz * (PI/180.0);
86			v->vn2 = v->vert * (PI/180.0);
87	greg	1.12	break;
88			case VT_HEM: /* hemispherical fisheye */
89			if (v->horiz > 180.0+FTINY)
90			return(ill_horiz);
91			if (v->vert > 180.0+FTINY)
92			return(ill_vert);
93			v->hn2 = 2.0 * sin(v->horiz*(PI/180.0/2.0));
94			v->vn2 = 2.0 * sin(v->vert*(PI/180.0/2.0));
95			break;
96	greg	2.34	case VT_PLS: /* planispheric fisheye */
97			if (v->horiz >= 360.0-FTINY)
98			return(ill_horiz);
99			if (v->vert >= 360.0-FTINY)
100			return(ill_vert);
101			v->hn2 = 2.sin(v->horiz(PI/180.0/2.0)) /
102			(1.0 + cos(v->horiz*(PI/180.0/2.0)));
103			v->vn2 = 2.sin(v->vert(PI/180.0/2.0)) /
104			(1.0 + cos(v->vert*(PI/180.0/2.0)));
105			break;
106	greg	1.12	default:
107	greg	1.1	return("unknown view type");
108	greg	1.12	}
109	greg	2.34	if (v->type != VT_ANG && v->type != VT_PLS) {
110	greg	2.9	if (v->type != VT_CYL) {
111			v->hvec[0] *= v->hn2;
112			v->hvec[1] *= v->hn2;
113			v->hvec[2] *= v->hn2;
114			}
115	greg	1.12	v->vvec[0] *= v->vn2;
116			v->vvec[1] *= v->vn2;
117			v->vvec[2] *= v->vn2;
118			}
119	greg	1.5	v->hn2 *= v->hn2;
120			v->vn2 *= v->vn2;
121	greg	1.1
122			return(NULL);
123			}
124
125
126	greg	2.16	void
127	greg	1.7	normaspect(va, ap, xp, yp) /* fix pixel aspect or resolution */
128			double va; /* view aspect ratio */
129			double ap; / pixel aspect in (or out if 0) */
130			int xp, yp; /* x and y resolution in (or out if ap!=0) /
131	greg	1.6	{
132			if (*ap <= FTINY)
133	greg	1.7	ap = va xp / yp; /* compute pixel aspect */
134	greg	1.6	else if (va * xp > ap * *yp)
135	greg	1.10	xp = yp / va * ap + .5; / reduce x resolution */
136	greg	1.6	else
137	greg	1.10	yp = xp * va / ap + .5; / reduce y resolution */
138	greg	1.6	}
139
140
141	greg	2.7	double
142	greg	1.5	viewray(orig, direc, v, x, y) /* compute ray origin and direction */
143	greg	1.1	FVECT orig, direc;
144			register VIEW *v;
145			double x, y;
146			{
147	greg	1.12	double d, z;
148
149	greg	1.5	x += v->hoff - 0.5;
150			y += v->voff - 0.5;
151	greg	1.1
152	greg	1.12	switch(v->type) {
153			case VT_PAR: /* parallel view */
154	greg	2.7	orig[0] = v->vp[0] + v->vfore*v->vdir[0]
155			+ xv->hvec[0] + yv->vvec[0];
156			orig[1] = v->vp[1] + v->vfore*v->vdir[1]
157			+ xv->hvec[1] + yv->vvec[1];
158			orig[2] = v->vp[2] + v->vfore*v->vdir[2]
159			+ xv->hvec[2] + yv->vvec[2];
160	greg	1.1	VCOPY(direc, v->vdir);
161	greg	2.8	return(v->vaft > FTINY ? v->vaft - v->vfore : 0.0);
162	greg	1.12	case VT_PER: /* perspective view */
163	greg	1.5	direc[0] = v->vdir[0] + xv->hvec[0] + yv->vvec[0];
164			direc[1] = v->vdir[1] + xv->hvec[1] + yv->vvec[1];
165			direc[2] = v->vdir[2] + xv->hvec[2] + yv->vvec[2];
166	greg	2.7	orig[0] = v->vp[0] + v->vfore*direc[0];
167			orig[1] = v->vp[1] + v->vfore*direc[1];
168			orig[2] = v->vp[2] + v->vfore*direc[2];
169			d = normalize(direc);
170	greg	2.8	return(v->vaft > FTINY ? (v->vaft - v->vfore)*d : 0.0);
171	greg	1.12	case VT_HEM: /* hemispherical fisheye */
172	greg	1.13	z = 1.0 - xxv->hn2 - yyv->vn2;
173	greg	1.12	if (z < 0.0)
174	greg	2.7	return(-1.0);
175	greg	1.12	z = sqrt(z);
176			direc[0] = zv->vdir[0] + xv->hvec[0] + y*v->vvec[0];
177			direc[1] = zv->vdir[1] + xv->hvec[1] + y*v->vvec[1];
178			direc[2] = zv->vdir[2] + xv->hvec[2] + y*v->vvec[2];
179	greg	2.7	orig[0] = v->vp[0] + v->vfore*direc[0];
180			orig[1] = v->vp[1] + v->vfore*direc[1];
181			orig[2] = v->vp[2] + v->vfore*direc[2];
182	greg	2.8	return(v->vaft > FTINY ? v->vaft - v->vfore : 0.0);
183	greg	2.9	case VT_CYL: /* cylindrical panorama */
184			d = x * v->horiz * (PI/180.0);
185			z = cos(d);
186			x = sin(d);
187			direc[0] = zv->vdir[0] + xv->hvec[0] + y*v->vvec[0];
188			direc[1] = zv->vdir[1] + xv->hvec[1] + y*v->vvec[1];
189			direc[2] = zv->vdir[2] + xv->hvec[2] + y*v->vvec[2];
190			orig[0] = v->vp[0] + v->vfore*direc[0];
191			orig[1] = v->vp[1] + v->vfore*direc[1];
192			orig[2] = v->vp[2] + v->vfore*direc[2];
193			d = normalize(direc);
194			return(v->vaft > FTINY ? (v->vaft - v->vfore)*d : 0.0);
195	greg	1.12	case VT_ANG: /* angular fisheye */
196	greg	2.34	x = (1.0/180.0)v->horiz;
197			y = (1.0/180.0)v->vert;
198	greg	1.12	d = xx + yy;
199			if (d > 1.0)
200	greg	2.7	return(-1.0);
201	greg	1.12	d = sqrt(d);
202			z = cos(PI*d);
203	greg	2.34	d = d <= FTINY ? PI : sqrt(1.0 - z*z)/d;
204			x *= d;
205			y *= d;
206			direc[0] = zv->vdir[0] + xv->hvec[0] + y*v->vvec[0];
207			direc[1] = zv->vdir[1] + xv->hvec[1] + y*v->vvec[1];
208			direc[2] = zv->vdir[2] + xv->hvec[2] + y*v->vvec[2];
209			orig[0] = v->vp[0] + v->vfore*direc[0];
210			orig[1] = v->vp[1] + v->vfore*direc[1];
211			orig[2] = v->vp[2] + v->vfore*direc[2];
212			return(v->vaft > FTINY ? v->vaft - v->vfore : 0.0);
213			case VT_PLS: /* planispheric fisheye */
214			x *= sqrt(v->hn2);
215			y *= sqrt(v->vn2);
216			d = xx + yy;
217			z = (1. - d)/(1. + d);
218			d = d <= FTINYFTINY ? PI : sqrt((1.0 - zz)/d);
219	greg	1.12	x *= d;
220			y *= d;
221			direc[0] = zv->vdir[0] + xv->hvec[0] + y*v->vvec[0];
222			direc[1] = zv->vdir[1] + xv->hvec[1] + y*v->vvec[1];
223			direc[2] = zv->vdir[2] + xv->hvec[2] + y*v->vvec[2];
224	greg	2.7	orig[0] = v->vp[0] + v->vfore*direc[0];
225			orig[1] = v->vp[1] + v->vfore*direc[1];
226			orig[2] = v->vp[2] + v->vfore*direc[2];
227	greg	2.8	return(v->vaft > FTINY ? v->vaft - v->vfore : 0.0);
228	greg	1.1	}
229	greg	2.7	return(-1.0);
230	greg	1.1	}
231
232
233	greg	2.16	void
234	greg	1.17	viewloc(ip, v, p) /* find image location for point */
235			FVECT ip;
236	greg	1.3	register VIEW *v;
237			FVECT p;
238			{
239	gregl	2.13	double d, d2;
240	greg	1.3	FVECT disp;
241	greg	1.5
242	greg	2.34	VSUB(disp, p, v->vp);
243	greg	1.3
244	greg	1.12	switch (v->type) {
245			case VT_PAR: /* parallel view */
246	greg	2.7	ip[2] = DOT(disp,v->vdir) - v->vfore;
247	greg	1.13	break;
248	greg	1.12	case VT_PER: /* perspective view */
249	greg	1.11	d = DOT(disp,v->vdir);
250	gregl	2.13	ip[2] = VLEN(disp);
251	greg	1.17	if (d < 0.0) { /* fold pyramid */
252			ip[2] = -ip[2];
253	greg	1.11	d = -d;
254	greg	2.7	}
255			if (d > FTINY) {
256	greg	1.11	d = 1.0/d;
257			disp[0] *= d;
258			disp[1] *= d;
259			disp[2] *= d;
260			}
261	greg	2.7	ip[2] = (1.0 - v->vfored);
262	greg	1.13	break;
263	greg	1.12	case VT_HEM: /* hemispherical fisheye */
264			d = normalize(disp);
265	greg	1.17	if (DOT(disp,v->vdir) < 0.0)
266			ip[2] = -d;
267			else
268			ip[2] = d;
269	greg	2.7	ip[2] -= v->vfore;
270	greg	1.13	break;
271	greg	2.9	case VT_CYL: /* cylindrical panorama */
272			d = DOT(disp,v->hvec);
273	gregl	2.13	d2 = DOT(disp,v->vdir);
274			ip[0] = 180.0/PI * atan2(d,d2) / v->horiz + 0.5 - v->hoff;
275			d = 1.0/sqrt(dd + d2d2);
276			ip[1] = DOT(disp,v->vvec)*d/v->vn2 + 0.5 - v->voff;
277			ip[2] = VLEN(disp);
278	gwlarson	2.15	ip[2] = (1.0 - v->vfored);
279	greg	2.9	return;
280	greg	1.12	case VT_ANG: /* angular fisheye */
281	greg	1.17	ip[0] = 0.5 - v->hoff;
282			ip[1] = 0.5 - v->voff;
283	greg	2.7	ip[2] = normalize(disp) - v->vfore;
284	greg	1.12	d = DOT(disp,v->vdir);
285			if (d >= 1.0-FTINY)
286			return;
287			if (d <= -(1.0-FTINY)) {
288	greg	2.7	ip[0] += 180.0/v->horiz;
289	greg	1.12	return;
290			}
291	greg	2.34	d = (180.0/PI)acos(d) / sqrt(1.0 - dd);
292			ip[0] += DOT(disp,v->hvec)*d/v->horiz;
293			ip[1] += DOT(disp,v->vvec)*d/v->vert;
294			return;
295			case VT_PLS: /* planispheric fisheye */
296			ip[0] = 0.5 - v->hoff;
297			ip[1] = 0.5 - v->voff;
298			ip[2] = normalize(disp) - v->vfore;
299			d = DOT(disp,v->vdir);
300			if (d >= 1.0-FTINY)
301			return;
302			if (d <= -(1.0-FTINY))
303			return; /* really an error */
304			d = sqrt(1.0 - d*d) / (1.0 + d);
305			ip[0] += DOT(disp,v->hvec)*d/sqrt(v->hn2);
306			ip[1] += DOT(disp,v->vvec)*d/sqrt(v->vn2);
307	greg	1.12	return;
308	greg	1.3	}
309	greg	1.17	ip[0] = DOT(disp,v->hvec)/v->hn2 + 0.5 - v->hoff;
310			ip[1] = DOT(disp,v->vvec)/v->vn2 + 0.5 - v->voff;
311	greg	1.3	}
312
313
314	greg	2.16	void
315	greg	1.17	pix2loc(loc, rp, px, py) /* compute image location from pixel pos. */
316	schorsch	2.18	RREAL loc[2];
317	greg	1.17	register RESOLU *rp;
318			int px, py;
319			{
320			register int x, y;
321
322	greg	2.16	if (rp->rt & YMAJOR) {
323	greg	1.17	x = px;
324			y = py;
325			} else {
326			x = py;
327			y = px;
328			}
329	greg	2.16	if (rp->rt & XDECR)
330	greg	1.17	x = rp->xr-1 - x;
331	greg	2.16	if (rp->rt & YDECR)
332	greg	1.17	y = rp->yr-1 - y;
333			loc[0] = (x+.5)/rp->xr;
334			loc[1] = (y+.5)/rp->yr;
335			}
336
337
338	greg	2.16	void
339	greg	1.17	loc2pix(pp, rp, lx, ly) /* compute pixel pos. from image location */
340			int pp[2];
341			register RESOLU *rp;
342			double lx, ly;
343			{
344			register int x, y;
345
346			x = lx * rp->xr;
347			y = ly * rp->yr;
348	greg	2.16	if (rp->rt & XDECR)
349	greg	1.17	x = rp->xr-1 - x;
350	greg	2.16	if (rp->rt & YDECR)
351	greg	1.17	y = rp->yr-1 - y;
352	greg	2.16	if (rp->rt & YMAJOR) {
353	greg	1.17	pp[0] = x;
354			pp[1] = y;
355			} else {
356			pp[0] = y;
357			pp[1] = x;
358			}
359			}
360
361
362	greg	1.5	int
363			getviewopt(v, ac, av) /* process view argument */
364			register VIEW *v;
365			int ac;
366			register char *av[];
367			{
368	greg	1.16	#define check(c,l) if ((av[0][c]&&av[0][c]!=' ') \|\| \
369			badarg(ac-1,av+1,l)) return(-1)
370	greg	1.5
371	greg	1.9	if (ac <= 0 \|\| av[0][0] != '-' \|\| av[0][1] != 'v')
372	greg	1.5	return(-1);
373			switch (av[0][2]) {
374			case 't': /* type */
375			if (!av[0][3] \|\| av[0][3]==' ')
376			return(-1);
377	greg	1.16	check(4,"");
378	greg	1.5	v->type = av[0][3];
379			return(0);
380			case 'p': /* point */
381	greg	1.16	check(3,"fff");
382	greg	1.5	v->vp[0] = atof(av[1]);
383			v->vp[1] = atof(av[2]);
384			v->vp[2] = atof(av[3]);
385			return(3);
386			case 'd': /* direction */
387	greg	1.16	check(3,"fff");
388	greg	1.5	v->vdir[0] = atof(av[1]);
389			v->vdir[1] = atof(av[2]);
390			v->vdir[2] = atof(av[3]);
391	greg	2.30	v->vdist = 1.;
392	greg	1.5	return(3);
393			case 'u': /* up */
394	greg	1.16	check(3,"fff");
395	greg	1.5	v->vup[0] = atof(av[1]);
396			v->vup[1] = atof(av[2]);
397			v->vup[2] = atof(av[3]);
398			return(3);
399			case 'h': /* horizontal size */
400	greg	1.16	check(3,"f");
401	greg	1.5	v->horiz = atof(av[1]);
402			return(1);
403			case 'v': /* vertical size */
404	greg	1.16	check(3,"f");
405	greg	1.5	v->vert = atof(av[1]);
406			return(1);
407	greg	2.7	case 'o': /* fore clipping plane */
408			check(3,"f");
409			v->vfore = atof(av[1]);
410			return(1);
411			case 'a': /* aft clipping plane */
412			check(3,"f");
413			v->vaft = atof(av[1]);
414			return(1);
415	greg	1.5	case 's': /* shift */
416	greg	1.16	check(3,"f");
417	greg	1.5	v->hoff = atof(av[1]);
418			return(1);
419			case 'l': /* lift */
420	greg	1.16	check(3,"f");
421	greg	1.5	v->voff = atof(av[1]);
422			return(1);
423			default:
424			return(-1);
425			}
426			#undef check
427			}
428
429
430			int
431			sscanview(vp, s) /* get view parameters from string */
432			VIEW *vp;
433	greg	1.1	register char *s;
434			{
435	greg	1.5	int ac;
436			char *av[4];
437			int na;
438			int nvopts = 0;
439
440	greg	2.32	while (isspace(*s))
441			if (!*s++)
442			return(0);
443	greg	1.9	while (*s) {
444	greg	1.5	ac = 0;
445			do {
446	greg	2.21	if (ac \|\| *s == '-')
447			av[ac++] = s;
448	greg	2.32	while (s && !isspace(s))
449	greg	1.5	s++;
450	greg	2.32	while (isspace(*s))
451	greg	1.5	s++;
452			} while (*s && ac < 4);
453			if ((na = getviewopt(vp, ac, av)) >= 0) {
454			if (na+1 < ac)
455			s = av[na+1];
456			nvopts++;
457	greg	1.9	} else if (ac > 1)
458			s = av[1];
459			}
460	greg	1.5	return(nvopts);
461	greg	1.1	}
462
463
464	greg	2.16	void
465	greg	1.1	fprintview(vp, fp) /* write out view parameters */
466			register VIEW *vp;
467			FILE *fp;
468			{
469			fprintf(fp, " -vt%c", vp->type);
470			fprintf(fp, " -vp %.6g %.6g %.6g", vp->vp[0], vp->vp[1], vp->vp[2]);
471	greg	2.29	fprintf(fp, " -vd %.6g %.6g %.6g", vp->vdir[0]*vp->vdist,
472			vp->vdir[1]*vp->vdist,
473			vp->vdir[2]*vp->vdist);
474	greg	1.1	fprintf(fp, " -vu %.6g %.6g %.6g", vp->vup[0], vp->vup[1], vp->vup[2]);
475			fprintf(fp, " -vh %.6g -vv %.6g", vp->horiz, vp->vert);
476	greg	2.7	fprintf(fp, " -vo %.6g -va %.6g", vp->vfore, vp->vaft);
477	greg	1.9	fprintf(fp, " -vs %.6g -vl %.6g", vp->hoff, vp->voff);
478	greg	2.11	}
479
480
481			char *
482			viewopt(vp) /* translate to minimal view string */
483			register VIEW *vp;
484			{
485			static char vwstr[128];
486			register char *cp = vwstr;
487
488	greg	2.33	*cp = '\0';
489	greg	2.11	if (vp->type != stdview.type) {
490			sprintf(cp, " -vt%c", vp->type);
491			cp += strlen(cp);
492			}
493			if (!VEQ(vp->vp,stdview.vp)) {
494			sprintf(cp, " -vp %.6g %.6g %.6g",
495			vp->vp[0], vp->vp[1], vp->vp[2]);
496			cp += strlen(cp);
497			}
498	greg	2.29	if (!FEQ(vp->vdist,stdview.vdist) \|\| !VEQ(vp->vdir,stdview.vdir)) {
499	greg	2.11	sprintf(cp, " -vd %.6g %.6g %.6g",
500	greg	2.29	vp->vdir[0]*vp->vdist,
501			vp->vdir[1]*vp->vdist,
502			vp->vdir[2]*vp->vdist);
503	greg	2.11	cp += strlen(cp);
504			}
505			if (!VEQ(vp->vup,stdview.vup)) {
506			sprintf(cp, " -vu %.6g %.6g %.6g",
507			vp->vup[0], vp->vup[1], vp->vup[2]);
508			cp += strlen(cp);
509			}
510			if (!FEQ(vp->horiz,stdview.horiz)) {
511			sprintf(cp, " -vh %.6g", vp->horiz);
512			cp += strlen(cp);
513			}
514			if (!FEQ(vp->vert,stdview.vert)) {
515			sprintf(cp, " -vv %.6g", vp->vert);
516			cp += strlen(cp);
517			}
518			if (!FEQ(vp->vfore,stdview.vfore)) {
519			sprintf(cp, " -vo %.6g", vp->vfore);
520			cp += strlen(cp);
521			}
522			if (!FEQ(vp->vaft,stdview.vaft)) {
523			sprintf(cp, " -va %.6g", vp->vaft);
524			cp += strlen(cp);
525			}
526			if (!FEQ(vp->hoff,stdview.hoff)) {
527			sprintf(cp, " -vs %.6g", vp->hoff);
528			cp += strlen(cp);
529			}
530			if (!FEQ(vp->voff,stdview.voff)) {
531			sprintf(cp, " -vl %.6g", vp->voff);
532			cp += strlen(cp);
533			}
534			return(vwstr);
535	greg	1.1	}
536
537
538	greg	2.3	int
539			isview(s) /* is this a view string? */
540			char *s;
541			{
542	greg	2.25	static char *altname[]={NULL,VIEWSTR,"rpict","rview","rvu","rpiece","pinterp",NULL};
543	greg	2.5	extern char *progname;
544	greg	2.3	register char *cp;
545			register char **an;
546			/* add program name to list */
547	greg	2.5	if (altname[0] == NULL) {
548			for (cp = progname; *cp; cp++)
549			;
550			while (cp > progname && !ISDIRSEP(cp[-1]))
551			cp--;
552			altname[0] = cp;
553			}
554	greg	2.3	/* skip leading path */
555			cp = s;
556			while (cp && cp != ' ')
557			cp++;
558	greg	2.5	while (cp > s && !ISDIRSEP(cp[-1]))
559	greg	2.3	cp--;
560			for (an = altname; *an != NULL; an++)
561			if (!strncmp(an, cp, strlen(an)))
562			return(1);
563			return(0);
564			}
565	greg	1.1
566	greg	2.3
567	greg	1.15	struct myview {
568			VIEW *hv;
569			int ok;
570			};
571	greg	1.1
572	greg	1.15
573	gwlarson	2.14	static int
574	schorsch	2.26	gethview( /* get view from header */
575			char *s,
576			void *v
577			)
578	greg	1.1	{
579	schorsch	2.26	if (isview(s) && sscanview(((struct myview*)v)->hv, s) > 0)
580			((struct myview*)v)->ok++;
581	gwlarson	2.14	return(0);
582	greg	1.1	}
583
584
585			int
586	greg	1.17	viewfile(fname, vp, rp) /* get view from file */
587	greg	1.1	char *fname;
588			VIEW *vp;
589	greg	1.17	RESOLU *rp;
590	greg	1.1	{
591	greg	1.15	struct myview mvs;
592	greg	1.1	FILE *fp;
593
594	greg	2.16	if (fname == NULL \|\| !strcmp(fname, "-"))
595			fp = stdin;
596			else if ((fp = fopen(fname, "r")) == NULL)
597	greg	1.1	return(-1);
598
599	greg	1.15	mvs.hv = vp;
600			mvs.ok = 0;
601	greg	1.1
602	schorsch	2.26	getheader(fp, gethview, &mvs);
603	greg	1.8
604	greg	1.17	if (rp != NULL && !fgetsresolu(rp, fp))
605	greg	1.15	mvs.ok = 0;
606	greg	1.1
607			fclose(fp);
608
609	greg	1.15	return(mvs.ok);
610	greg	1.1	}