src/common/image.c

/* Copyright (c) 1996 Regents of the University of California */

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

/*
 *  image.c - routines for image generation.
 */

#include  "standard.h"

#include  "view.h"

#include  "resolu.h"

#include  "paths.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 */


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->vfore < -FTINY || v->vaft < -FTINY ||
                        (v->vaft > FTINY && v->vaft <= v->vfore))
                return("illegal fore/aft clipping plane");

        if (normalize(v->vdir) == 0.0)          /* normalize direction */
                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;
        default:
                return("unknown view type");
        }
        if (v->type != VT_ANG) {
                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);
}


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 *= v->horiz/180.0;
                y *= v->vert/180.0;
                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 - 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);
}


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

        disp[0] = p[0] - v->vp[0];
        disp[1] = p[1] - v->vp[1];
        disp[2] = p[2] - v->vp[2];

        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);
                if (v->vfore > FTINY)
                        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 = acos(d)/PI / sqrt(1.0 - d*d);
                ip[0] += DOT(disp,v->hvec)*d*180.0/v->horiz;
                ip[1] += DOT(disp,v->vvec)*d*180.0/v->vert;
                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;
}


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

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


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->or & XDECR)
                x = rp->xr-1 - x;
        if (rp->or & YDECR)
                y = rp->yr-1 - y;
        if (rp->or & 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]);
                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;

        if (*s != '-')
                s = sskip2(s,1);
        while (*s) {
                ac = 0;
                do {
                        av[ac++] = s;
                        while (*s && *s != ' ')
                                s++;
                        while (*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);
}


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->vdir[1], vp->vdir[2]);
        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;

        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 (!VEQ(vp->vdir,stdview.vdir)) {
                sprintf(cp, " -vd %.6g %.6g %.6g",
                                vp->vdir[0], vp->vdir[1], vp->vdir[2]);
                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","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
gethview(s, v)                          /* get view from header */
char  *s;
register struct myview  *v;
{
        if (isview(s) && sscanview(v->hv, s) > 0)
                v->ok++;
}


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

        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:	2.13
Committed:	Tue Dec 9 16:41:03 1997 UTC (27 years, 10 months ago) by gregl
Content type:	text/plain
Branch:	MAIN
Changes since 2.12:	+8 -9 lines
Log Message:	fixed computation for VT_CYL in viewloc() -- at last!
#	User	Rev	Content
1	greg	2.11	/* Copyright (c) 1996 Regents of the University of California */
2	greg	1.1
3			#ifndef lint
4			static char SCCSid[] = "$SunId$ LBL";
5			#endif
6
7			/*
8			* image.c - routines for image generation.
9			*/
10
11			#include "standard.h"
12
13			#include "view.h"
14
15	greg	1.17	#include "resolu.h"
16
17	greg	2.4	#include "paths.h"
18
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
26			char *
27	greg	1.5	setview(v) /* set hvec and vvec, return message on error */
28			register VIEW *v;
29	greg	1.3	{
30	greg	1.12	static char ill_horiz[] = "illegal horizontal view size";
31			static char ill_vert[] = "illegal vertical view size";
32
33	greg	2.7	if (v->vfore < -FTINY \|\| v->vaft < -FTINY \|\|
34			(v->vaft > FTINY && v->vaft <= v->vfore))
35			return("illegal fore/aft clipping plane");
36
37	greg	1.1	if (normalize(v->vdir) == 0.0) /* normalize direction */
38			return("zero view direction");
39
40	greg	1.14	if (normalize(v->vup) == 0.0) /* normalize view up */
41			return("zero view up vector");
42
43	greg	1.5	fcross(v->hvec, v->vdir, v->vup); /* compute horiz dir */
44
45			if (normalize(v->hvec) == 0.0)
46	greg	1.14	return("view up parallel to view direction");
47	greg	1.1
48	greg	1.5	fcross(v->vvec, v->hvec, v->vdir); /* compute vert dir */
49
50	greg	1.12	if (v->horiz <= FTINY)
51			return(ill_horiz);
52			if (v->vert <= FTINY)
53			return(ill_vert);
54
55			switch (v->type) {
56			case VT_PAR: /* parallel view */
57	greg	1.5	v->hn2 = v->horiz;
58	greg	1.12	v->vn2 = v->vert;
59			break;
60			case VT_PER: /* perspective view */
61			if (v->horiz >= 180.0-FTINY)
62			return(ill_horiz);
63			if (v->vert >= 180.0-FTINY)
64			return(ill_vert);
65	greg	1.5	v->hn2 = 2.0 * tan(v->horiz*(PI/180.0/2.0));
66	greg	1.12	v->vn2 = 2.0 * tan(v->vert*(PI/180.0/2.0));
67			break;
68	greg	2.9	case VT_CYL: /* cylindrical panorama */
69			if (v->horiz > 360.0+FTINY)
70			return(ill_horiz);
71			if (v->vert >= 180.0-FTINY)
72			return(ill_vert);
73			v->hn2 = v->horiz * (PI/180.0);
74			v->vn2 = 2.0 * tan(v->vert*(PI/180.0/2.0));
75			break;
76	greg	1.12	case VT_ANG: /* angular fisheye */
77			if (v->horiz > 360.0+FTINY)
78			return(ill_horiz);
79			if (v->vert > 360.0+FTINY)
80			return(ill_vert);
81	greg	2.9	v->hn2 = v->horiz * (PI/180.0);
82			v->vn2 = v->vert * (PI/180.0);
83	greg	1.12	break;
84			case VT_HEM: /* hemispherical fisheye */
85			if (v->horiz > 180.0+FTINY)
86			return(ill_horiz);
87			if (v->vert > 180.0+FTINY)
88			return(ill_vert);
89			v->hn2 = 2.0 * sin(v->horiz*(PI/180.0/2.0));
90			v->vn2 = 2.0 * sin(v->vert*(PI/180.0/2.0));
91			break;
92			default:
93	greg	1.1	return("unknown view type");
94	greg	1.12	}
95	greg	1.13	if (v->type != VT_ANG) {
96	greg	2.9	if (v->type != VT_CYL) {
97			v->hvec[0] *= v->hn2;
98			v->hvec[1] *= v->hn2;
99			v->hvec[2] *= v->hn2;
100			}
101	greg	1.12	v->vvec[0] *= v->vn2;
102			v->vvec[1] *= v->vn2;
103			v->vvec[2] *= v->vn2;
104			}
105	greg	1.5	v->hn2 *= v->hn2;
106			v->vn2 *= v->vn2;
107	greg	1.1
108			return(NULL);
109			}
110
111
112	greg	1.7	normaspect(va, ap, xp, yp) /* fix pixel aspect or resolution */
113			double va; /* view aspect ratio */
114			double ap; / pixel aspect in (or out if 0) */
115			int xp, yp; /* x and y resolution in (or out if ap!=0) /
116	greg	1.6	{
117			if (*ap <= FTINY)
118	greg	1.7	ap = va xp / yp; /* compute pixel aspect */
119	greg	1.6	else if (va * xp > ap * *yp)
120	greg	1.10	xp = yp / va * ap + .5; / reduce x resolution */
121	greg	1.6	else
122	greg	1.10	yp = xp * va / ap + .5; / reduce y resolution */
123	greg	1.6	}
124
125
126	greg	2.7	double
127	greg	1.5	viewray(orig, direc, v, x, y) /* compute ray origin and direction */
128	greg	1.1	FVECT orig, direc;
129			register VIEW *v;
130			double x, y;
131			{
132	greg	1.12	double d, z;
133
134	greg	1.5	x += v->hoff - 0.5;
135			y += v->voff - 0.5;
136	greg	1.1
137	greg	1.12	switch(v->type) {
138			case VT_PAR: /* parallel view */
139	greg	2.7	orig[0] = v->vp[0] + v->vfore*v->vdir[0]
140			+ xv->hvec[0] + yv->vvec[0];
141			orig[1] = v->vp[1] + v->vfore*v->vdir[1]
142			+ xv->hvec[1] + yv->vvec[1];
143			orig[2] = v->vp[2] + v->vfore*v->vdir[2]
144			+ xv->hvec[2] + yv->vvec[2];
145	greg	1.1	VCOPY(direc, v->vdir);
146	greg	2.8	return(v->vaft > FTINY ? v->vaft - v->vfore : 0.0);
147	greg	1.12	case VT_PER: /* perspective view */
148	greg	1.5	direc[0] = v->vdir[0] + xv->hvec[0] + yv->vvec[0];
149			direc[1] = v->vdir[1] + xv->hvec[1] + yv->vvec[1];
150			direc[2] = v->vdir[2] + xv->hvec[2] + yv->vvec[2];
151	greg	2.7	orig[0] = v->vp[0] + v->vfore*direc[0];
152			orig[1] = v->vp[1] + v->vfore*direc[1];
153			orig[2] = v->vp[2] + v->vfore*direc[2];
154			d = normalize(direc);
155	greg	2.8	return(v->vaft > FTINY ? (v->vaft - v->vfore)*d : 0.0);
156	greg	1.12	case VT_HEM: /* hemispherical fisheye */
157	greg	1.13	z = 1.0 - xxv->hn2 - yyv->vn2;
158	greg	1.12	if (z < 0.0)
159	greg	2.7	return(-1.0);
160	greg	1.12	z = sqrt(z);
161			direc[0] = zv->vdir[0] + xv->hvec[0] + y*v->vvec[0];
162			direc[1] = zv->vdir[1] + xv->hvec[1] + y*v->vvec[1];
163			direc[2] = zv->vdir[2] + xv->hvec[2] + y*v->vvec[2];
164	greg	2.7	orig[0] = v->vp[0] + v->vfore*direc[0];
165			orig[1] = v->vp[1] + v->vfore*direc[1];
166			orig[2] = v->vp[2] + v->vfore*direc[2];
167	greg	2.8	return(v->vaft > FTINY ? v->vaft - v->vfore : 0.0);
168	greg	2.9	case VT_CYL: /* cylindrical panorama */
169			d = x * v->horiz * (PI/180.0);
170			z = cos(d);
171			x = sin(d);
172			direc[0] = zv->vdir[0] + xv->hvec[0] + y*v->vvec[0];
173			direc[1] = zv->vdir[1] + xv->hvec[1] + y*v->vvec[1];
174			direc[2] = zv->vdir[2] + xv->hvec[2] + y*v->vvec[2];
175			orig[0] = v->vp[0] + v->vfore*direc[0];
176			orig[1] = v->vp[1] + v->vfore*direc[1];
177			orig[2] = v->vp[2] + v->vfore*direc[2];
178			d = normalize(direc);
179			return(v->vaft > FTINY ? (v->vaft - v->vfore)*d : 0.0);
180	greg	1.12	case VT_ANG: /* angular fisheye */
181			x *= v->horiz/180.0;
182			y *= v->vert/180.0;
183			d = xx + yy;
184			if (d > 1.0)
185	greg	2.7	return(-1.0);
186	greg	1.12	d = sqrt(d);
187			z = cos(PI*d);
188	greg	2.6	d = d <= FTINY ? PI : sqrt(1 - z*z)/d;
189	greg	1.12	x *= d;
190			y *= d;
191			direc[0] = zv->vdir[0] + xv->hvec[0] + y*v->vvec[0];
192			direc[1] = zv->vdir[1] + xv->hvec[1] + y*v->vvec[1];
193			direc[2] = zv->vdir[2] + xv->hvec[2] + y*v->vvec[2];
194	greg	2.7	orig[0] = v->vp[0] + v->vfore*direc[0];
195			orig[1] = v->vp[1] + v->vfore*direc[1];
196			orig[2] = v->vp[2] + v->vfore*direc[2];
197	greg	2.8	return(v->vaft > FTINY ? v->vaft - v->vfore : 0.0);
198	greg	1.1	}
199	greg	2.7	return(-1.0);
200	greg	1.1	}
201
202
203	greg	1.17	viewloc(ip, v, p) /* find image location for point */
204			FVECT ip;
205	greg	1.3	register VIEW *v;
206			FVECT p;
207			{
208	gregl	2.13	double d, d2;
209	greg	1.3	FVECT disp;
210	greg	1.5
211	greg	1.3	disp[0] = p[0] - v->vp[0];
212			disp[1] = p[1] - v->vp[1];
213			disp[2] = p[2] - v->vp[2];
214
215	greg	1.12	switch (v->type) {
216			case VT_PAR: /* parallel view */
217	greg	2.7	ip[2] = DOT(disp,v->vdir) - v->vfore;
218	greg	1.13	break;
219	greg	1.12	case VT_PER: /* perspective view */
220	greg	1.11	d = DOT(disp,v->vdir);
221	gregl	2.13	ip[2] = VLEN(disp);
222	greg	1.17	if (d < 0.0) { /* fold pyramid */
223			ip[2] = -ip[2];
224	greg	1.11	d = -d;
225	greg	2.7	}
226			if (d > FTINY) {
227	greg	1.11	d = 1.0/d;
228			disp[0] *= d;
229			disp[1] *= d;
230			disp[2] *= d;
231			}
232	greg	2.7	ip[2] = (1.0 - v->vfored);
233	greg	1.13	break;
234	greg	1.12	case VT_HEM: /* hemispherical fisheye */
235			d = normalize(disp);
236	greg	1.17	if (DOT(disp,v->vdir) < 0.0)
237			ip[2] = -d;
238			else
239			ip[2] = d;
240	greg	2.7	ip[2] -= v->vfore;
241	greg	1.13	break;
242	greg	2.9	case VT_CYL: /* cylindrical panorama */
243			d = DOT(disp,v->hvec);
244	gregl	2.13	d2 = DOT(disp,v->vdir);
245			ip[0] = 180.0/PI * atan2(d,d2) / v->horiz + 0.5 - v->hoff;
246			d = 1.0/sqrt(dd + d2d2);
247			ip[1] = DOT(disp,v->vvec)*d/v->vn2 + 0.5 - v->voff;
248			ip[2] = VLEN(disp);
249	greg	2.9	if (v->vfore > FTINY)
250	gregl	2.13	ip[2] = (1.0 - v->vfored);
251	greg	2.9	return;
252	greg	1.12	case VT_ANG: /* angular fisheye */
253	greg	1.17	ip[0] = 0.5 - v->hoff;
254			ip[1] = 0.5 - v->voff;
255	greg	2.7	ip[2] = normalize(disp) - v->vfore;
256	greg	1.12	d = DOT(disp,v->vdir);
257			if (d >= 1.0-FTINY)
258			return;
259			if (d <= -(1.0-FTINY)) {
260	greg	2.7	ip[0] += 180.0/v->horiz;
261	greg	1.12	return;
262			}
263			d = acos(d)/PI / sqrt(1.0 - d*d);
264	greg	1.17	ip[0] += DOT(disp,v->hvec)d180.0/v->horiz;
265			ip[1] += DOT(disp,v->vvec)d180.0/v->vert;
266	greg	1.12	return;
267	greg	1.3	}
268	greg	1.17	ip[0] = DOT(disp,v->hvec)/v->hn2 + 0.5 - v->hoff;
269			ip[1] = DOT(disp,v->vvec)/v->vn2 + 0.5 - v->voff;
270	greg	1.3	}
271
272
273	greg	1.17	pix2loc(loc, rp, px, py) /* compute image location from pixel pos. */
274			FLOAT loc[2];
275			register RESOLU *rp;
276			int px, py;
277			{
278			register int x, y;
279
280			if (rp->or & YMAJOR) {
281			x = px;
282			y = py;
283			} else {
284			x = py;
285			y = px;
286			}
287			if (rp->or & XDECR)
288			x = rp->xr-1 - x;
289			if (rp->or & YDECR)
290			y = rp->yr-1 - y;
291			loc[0] = (x+.5)/rp->xr;
292			loc[1] = (y+.5)/rp->yr;
293			}
294
295
296			loc2pix(pp, rp, lx, ly) /* compute pixel pos. from image location */
297			int pp[2];
298			register RESOLU *rp;
299			double lx, ly;
300			{
301			register int x, y;
302
303			x = lx * rp->xr;
304			y = ly * rp->yr;
305			if (rp->or & XDECR)
306			x = rp->xr-1 - x;
307			if (rp->or & YDECR)
308			y = rp->yr-1 - y;
309			if (rp->or & YMAJOR) {
310			pp[0] = x;
311			pp[1] = y;
312			} else {
313			pp[0] = y;
314			pp[1] = x;
315			}
316			}
317
318
319	greg	1.5	int
320			getviewopt(v, ac, av) /* process view argument */
321			register VIEW *v;
322			int ac;
323			register char *av[];
324			{
325	greg	1.16	#define check(c,l) if ((av[0][c]&&av[0][c]!=' ') \|\| \
326			badarg(ac-1,av+1,l)) return(-1)
327	greg	1.5
328	greg	1.9	if (ac <= 0 \|\| av[0][0] != '-' \|\| av[0][1] != 'v')
329	greg	1.5	return(-1);
330			switch (av[0][2]) {
331			case 't': /* type */
332			if (!av[0][3] \|\| av[0][3]==' ')
333			return(-1);
334	greg	1.16	check(4,"");
335	greg	1.5	v->type = av[0][3];
336			return(0);
337			case 'p': /* point */
338	greg	1.16	check(3,"fff");
339	greg	1.5	v->vp[0] = atof(av[1]);
340			v->vp[1] = atof(av[2]);
341			v->vp[2] = atof(av[3]);
342			return(3);
343			case 'd': /* direction */
344	greg	1.16	check(3,"fff");
345	greg	1.5	v->vdir[0] = atof(av[1]);
346			v->vdir[1] = atof(av[2]);
347			v->vdir[2] = atof(av[3]);
348			return(3);
349			case 'u': /* up */
350	greg	1.16	check(3,"fff");
351	greg	1.5	v->vup[0] = atof(av[1]);
352			v->vup[1] = atof(av[2]);
353			v->vup[2] = atof(av[3]);
354			return(3);
355			case 'h': /* horizontal size */
356	greg	1.16	check(3,"f");
357	greg	1.5	v->horiz = atof(av[1]);
358			return(1);
359			case 'v': /* vertical size */
360	greg	1.16	check(3,"f");
361	greg	1.5	v->vert = atof(av[1]);
362			return(1);
363	greg	2.7	case 'o': /* fore clipping plane */
364			check(3,"f");
365			v->vfore = atof(av[1]);
366			return(1);
367			case 'a': /* aft clipping plane */
368			check(3,"f");
369			v->vaft = atof(av[1]);
370			return(1);
371	greg	1.5	case 's': /* shift */
372	greg	1.16	check(3,"f");
373	greg	1.5	v->hoff = atof(av[1]);
374			return(1);
375			case 'l': /* lift */
376	greg	1.16	check(3,"f");
377	greg	1.5	v->voff = atof(av[1]);
378			return(1);
379			default:
380			return(-1);
381			}
382			#undef check
383			}
384
385
386			int
387			sscanview(vp, s) /* get view parameters from string */
388			VIEW *vp;
389	greg	1.1	register char *s;
390			{
391	greg	1.5	int ac;
392			char *av[4];
393			int na;
394			int nvopts = 0;
395
396	greg	2.3	if (*s != '-')
397	greg	2.12	s = sskip2(s,1);
398	greg	1.9	while (*s) {
399	greg	1.5	ac = 0;
400			do {
401			av[ac++] = s;
402			while (s && s != ' ')
403			s++;
404			while (*s == ' ')
405			s++;
406			} while (*s && ac < 4);
407			if ((na = getviewopt(vp, ac, av)) >= 0) {
408			if (na+1 < ac)
409			s = av[na+1];
410			nvopts++;
411	greg	1.9	} else if (ac > 1)
412			s = av[1];
413			}
414	greg	1.5	return(nvopts);
415	greg	1.1	}
416
417
418			fprintview(vp, fp) /* write out view parameters */
419			register VIEW *vp;
420			FILE *fp;
421			{
422			fprintf(fp, " -vt%c", vp->type);
423			fprintf(fp, " -vp %.6g %.6g %.6g", vp->vp[0], vp->vp[1], vp->vp[2]);
424			fprintf(fp, " -vd %.6g %.6g %.6g", vp->vdir[0], vp->vdir[1], vp->vdir[2]);
425			fprintf(fp, " -vu %.6g %.6g %.6g", vp->vup[0], vp->vup[1], vp->vup[2]);
426			fprintf(fp, " -vh %.6g -vv %.6g", vp->horiz, vp->vert);
427	greg	2.7	fprintf(fp, " -vo %.6g -va %.6g", vp->vfore, vp->vaft);
428	greg	1.9	fprintf(fp, " -vs %.6g -vl %.6g", vp->hoff, vp->voff);
429	greg	2.11	}
430
431
432			char *
433			viewopt(vp) /* translate to minimal view string */
434			register VIEW *vp;
435			{
436			static char vwstr[128];
437			register char *cp = vwstr;
438
439			if (vp->type != stdview.type) {
440			sprintf(cp, " -vt%c", vp->type);
441			cp += strlen(cp);
442			}
443			if (!VEQ(vp->vp,stdview.vp)) {
444			sprintf(cp, " -vp %.6g %.6g %.6g",
445			vp->vp[0], vp->vp[1], vp->vp[2]);
446			cp += strlen(cp);
447			}
448			if (!VEQ(vp->vdir,stdview.vdir)) {
449			sprintf(cp, " -vd %.6g %.6g %.6g",
450			vp->vdir[0], vp->vdir[1], vp->vdir[2]);
451			cp += strlen(cp);
452			}
453			if (!VEQ(vp->vup,stdview.vup)) {
454			sprintf(cp, " -vu %.6g %.6g %.6g",
455			vp->vup[0], vp->vup[1], vp->vup[2]);
456			cp += strlen(cp);
457			}
458			if (!FEQ(vp->horiz,stdview.horiz)) {
459			sprintf(cp, " -vh %.6g", vp->horiz);
460			cp += strlen(cp);
461			}
462			if (!FEQ(vp->vert,stdview.vert)) {
463			sprintf(cp, " -vv %.6g", vp->vert);
464			cp += strlen(cp);
465			}
466			if (!FEQ(vp->vfore,stdview.vfore)) {
467			sprintf(cp, " -vo %.6g", vp->vfore);
468			cp += strlen(cp);
469			}
470			if (!FEQ(vp->vaft,stdview.vaft)) {
471			sprintf(cp, " -va %.6g", vp->vaft);
472			cp += strlen(cp);
473			}
474			if (!FEQ(vp->hoff,stdview.hoff)) {
475			sprintf(cp, " -vs %.6g", vp->hoff);
476			cp += strlen(cp);
477			}
478			if (!FEQ(vp->voff,stdview.voff)) {
479			sprintf(cp, " -vl %.6g", vp->voff);
480			cp += strlen(cp);
481			}
482			return(vwstr);
483	greg	1.1	}
484
485
486	greg	2.3	int
487			isview(s) /* is this a view string? */
488			char *s;
489			{
490	greg	2.5	static char *altname[]={NULL,VIEWSTR,"rpict","rview","pinterp",NULL};
491			extern char *progname;
492	greg	2.3	register char *cp;
493			register char **an;
494			/* add program name to list */
495	greg	2.5	if (altname[0] == NULL) {
496			for (cp = progname; *cp; cp++)
497			;
498			while (cp > progname && !ISDIRSEP(cp[-1]))
499			cp--;
500			altname[0] = cp;
501			}
502	greg	2.3	/* skip leading path */
503			cp = s;
504			while (cp && cp != ' ')
505			cp++;
506	greg	2.5	while (cp > s && !ISDIRSEP(cp[-1]))
507	greg	2.3	cp--;
508			for (an = altname; *an != NULL; an++)
509			if (!strncmp(an, cp, strlen(an)))
510			return(1);
511			return(0);
512			}
513	greg	1.1
514	greg	2.3
515	greg	1.15	struct myview {
516			VIEW *hv;
517			int ok;
518			};
519	greg	1.1
520	greg	1.15
521	greg	1.1	static
522	greg	1.15	gethview(s, v) /* get view from header */
523	greg	1.1	char *s;
524	greg	1.15	register struct myview *v;
525	greg	1.1	{
526	greg	2.3	if (isview(s) && sscanview(v->hv, s) > 0)
527			v->ok++;
528	greg	1.1	}
529
530
531			int
532	greg	1.17	viewfile(fname, vp, rp) /* get view from file */
533	greg	1.1	char *fname;
534			VIEW *vp;
535	greg	1.17	RESOLU *rp;
536	greg	1.1	{
537	greg	1.15	struct myview mvs;
538	greg	1.1	FILE *fp;
539
540			if ((fp = fopen(fname, "r")) == NULL)
541			return(-1);
542
543	greg	1.15	mvs.hv = vp;
544			mvs.ok = 0;
545	greg	1.1
546	greg	1.15	getheader(fp, gethview, &mvs);
547	greg	1.8
548	greg	1.17	if (rp != NULL && !fgetsresolu(rp, fp))
549	greg	1.15	mvs.ok = 0;
550	greg	1.1
551			fclose(fp);
552
553	greg	1.15	return(mvs.ok);
554	greg	1.1	}