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->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);
                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 int
gethview(s, v)                          /* get view from header */
char  *s;
register struct myview  *v;
{
        if (isview(s) && sscanview(v->hv, s) > 0)
                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 ((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:	2.15
Committed:	Fri Feb 26 12:24:07 1999 UTC (25 years, 2 months ago) by gwlarson
Content type:	text/plain
Branch:	MAIN
Changes since 2.14:	+2 -4 lines
Log Message:	allowed negative fore clipping plane for holographic rendering
#	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	gwlarson	2.15	if (v->vaft < -FTINY \|\| (v->vaft > FTINY && v->vaft <= v->vfore))
34	greg	2.7	return("illegal fore/aft clipping plane");
35
36	greg	1.1	if (normalize(v->vdir) == 0.0) /* normalize direction */
37			return("zero view direction");
38
39	greg	1.14	if (normalize(v->vup) == 0.0) /* normalize view up */
40			return("zero view up vector");
41
42	greg	1.5	fcross(v->hvec, v->vdir, v->vup); /* compute horiz dir */
43
44			if (normalize(v->hvec) == 0.0)
45	greg	1.14	return("view up parallel to view direction");
46	greg	1.1
47	greg	1.5	fcross(v->vvec, v->hvec, v->vdir); /* compute vert dir */
48
49	greg	1.12	if (v->horiz <= FTINY)
50			return(ill_horiz);
51			if (v->vert <= FTINY)
52			return(ill_vert);
53
54			switch (v->type) {
55			case VT_PAR: /* parallel view */
56	greg	1.5	v->hn2 = v->horiz;
57	greg	1.12	v->vn2 = v->vert;
58			break;
59			case VT_PER: /* perspective view */
60			if (v->horiz >= 180.0-FTINY)
61			return(ill_horiz);
62			if (v->vert >= 180.0-FTINY)
63			return(ill_vert);
64	greg	1.5	v->hn2 = 2.0 * tan(v->horiz*(PI/180.0/2.0));
65	greg	1.12	v->vn2 = 2.0 * tan(v->vert*(PI/180.0/2.0));
66			break;
67	greg	2.9	case VT_CYL: /* cylindrical panorama */
68			if (v->horiz > 360.0+FTINY)
69			return(ill_horiz);
70			if (v->vert >= 180.0-FTINY)
71			return(ill_vert);
72			v->hn2 = v->horiz * (PI/180.0);
73			v->vn2 = 2.0 * tan(v->vert*(PI/180.0/2.0));
74			break;
75	greg	1.12	case VT_ANG: /* angular fisheye */
76			if (v->horiz > 360.0+FTINY)
77			return(ill_horiz);
78			if (v->vert > 360.0+FTINY)
79			return(ill_vert);
80	greg	2.9	v->hn2 = v->horiz * (PI/180.0);
81			v->vn2 = v->vert * (PI/180.0);
82	greg	1.12	break;
83			case VT_HEM: /* hemispherical fisheye */
84			if (v->horiz > 180.0+FTINY)
85			return(ill_horiz);
86			if (v->vert > 180.0+FTINY)
87			return(ill_vert);
88			v->hn2 = 2.0 * sin(v->horiz*(PI/180.0/2.0));
89			v->vn2 = 2.0 * sin(v->vert*(PI/180.0/2.0));
90			break;
91			default:
92	greg	1.1	return("unknown view type");
93	greg	1.12	}
94	greg	1.13	if (v->type != VT_ANG) {
95	greg	2.9	if (v->type != VT_CYL) {
96			v->hvec[0] *= v->hn2;
97			v->hvec[1] *= v->hn2;
98			v->hvec[2] *= v->hn2;
99			}
100	greg	1.12	v->vvec[0] *= v->vn2;
101			v->vvec[1] *= v->vn2;
102			v->vvec[2] *= v->vn2;
103			}
104	greg	1.5	v->hn2 *= v->hn2;
105			v->vn2 *= v->vn2;
106	greg	1.1
107			return(NULL);
108			}
109
110
111	greg	1.7	normaspect(va, ap, xp, yp) /* fix pixel aspect or resolution */
112			double va; /* view aspect ratio */
113			double ap; / pixel aspect in (or out if 0) */
114			int xp, yp; /* x and y resolution in (or out if ap!=0) /
115	greg	1.6	{
116			if (*ap <= FTINY)
117	greg	1.7	ap = va xp / yp; /* compute pixel aspect */
118	greg	1.6	else if (va * xp > ap * *yp)
119	greg	1.10	xp = yp / va * ap + .5; / reduce x resolution */
120	greg	1.6	else
121	greg	1.10	yp = xp * va / ap + .5; / reduce y resolution */
122	greg	1.6	}
123
124
125	greg	2.7	double
126	greg	1.5	viewray(orig, direc, v, x, y) /* compute ray origin and direction */
127	greg	1.1	FVECT orig, direc;
128			register VIEW *v;
129			double x, y;
130			{
131	greg	1.12	double d, z;
132
133	greg	1.5	x += v->hoff - 0.5;
134			y += v->voff - 0.5;
135	greg	1.1
136	greg	1.12	switch(v->type) {
137			case VT_PAR: /* parallel view */
138	greg	2.7	orig[0] = v->vp[0] + v->vfore*v->vdir[0]
139			+ xv->hvec[0] + yv->vvec[0];
140			orig[1] = v->vp[1] + v->vfore*v->vdir[1]
141			+ xv->hvec[1] + yv->vvec[1];
142			orig[2] = v->vp[2] + v->vfore*v->vdir[2]
143			+ xv->hvec[2] + yv->vvec[2];
144	greg	1.1	VCOPY(direc, v->vdir);
145	greg	2.8	return(v->vaft > FTINY ? v->vaft - v->vfore : 0.0);
146	greg	1.12	case VT_PER: /* perspective view */
147	greg	1.5	direc[0] = v->vdir[0] + xv->hvec[0] + yv->vvec[0];
148			direc[1] = v->vdir[1] + xv->hvec[1] + yv->vvec[1];
149			direc[2] = v->vdir[2] + xv->hvec[2] + yv->vvec[2];
150	greg	2.7	orig[0] = v->vp[0] + v->vfore*direc[0];
151			orig[1] = v->vp[1] + v->vfore*direc[1];
152			orig[2] = v->vp[2] + v->vfore*direc[2];
153			d = normalize(direc);
154	greg	2.8	return(v->vaft > FTINY ? (v->vaft - v->vfore)*d : 0.0);
155	greg	1.12	case VT_HEM: /* hemispherical fisheye */
156	greg	1.13	z = 1.0 - xxv->hn2 - yyv->vn2;
157	greg	1.12	if (z < 0.0)
158	greg	2.7	return(-1.0);
159	greg	1.12	z = sqrt(z);
160			direc[0] = zv->vdir[0] + xv->hvec[0] + y*v->vvec[0];
161			direc[1] = zv->vdir[1] + xv->hvec[1] + y*v->vvec[1];
162			direc[2] = zv->vdir[2] + xv->hvec[2] + y*v->vvec[2];
163	greg	2.7	orig[0] = v->vp[0] + v->vfore*direc[0];
164			orig[1] = v->vp[1] + v->vfore*direc[1];
165			orig[2] = v->vp[2] + v->vfore*direc[2];
166	greg	2.8	return(v->vaft > FTINY ? v->vaft - v->vfore : 0.0);
167	greg	2.9	case VT_CYL: /* cylindrical panorama */
168			d = x * v->horiz * (PI/180.0);
169			z = cos(d);
170			x = sin(d);
171			direc[0] = zv->vdir[0] + xv->hvec[0] + y*v->vvec[0];
172			direc[1] = zv->vdir[1] + xv->hvec[1] + y*v->vvec[1];
173			direc[2] = zv->vdir[2] + xv->hvec[2] + y*v->vvec[2];
174			orig[0] = v->vp[0] + v->vfore*direc[0];
175			orig[1] = v->vp[1] + v->vfore*direc[1];
176			orig[2] = v->vp[2] + v->vfore*direc[2];
177			d = normalize(direc);
178			return(v->vaft > FTINY ? (v->vaft - v->vfore)*d : 0.0);
179	greg	1.12	case VT_ANG: /* angular fisheye */
180			x *= v->horiz/180.0;
181			y *= v->vert/180.0;
182			d = xx + yy;
183			if (d > 1.0)
184	greg	2.7	return(-1.0);
185	greg	1.12	d = sqrt(d);
186			z = cos(PI*d);
187	greg	2.6	d = d <= FTINY ? PI : sqrt(1 - z*z)/d;
188	greg	1.12	x *= d;
189			y *= d;
190			direc[0] = zv->vdir[0] + xv->hvec[0] + y*v->vvec[0];
191			direc[1] = zv->vdir[1] + xv->hvec[1] + y*v->vvec[1];
192			direc[2] = zv->vdir[2] + xv->hvec[2] + y*v->vvec[2];
193	greg	2.7	orig[0] = v->vp[0] + v->vfore*direc[0];
194			orig[1] = v->vp[1] + v->vfore*direc[1];
195			orig[2] = v->vp[2] + v->vfore*direc[2];
196	greg	2.8	return(v->vaft > FTINY ? v->vaft - v->vfore : 0.0);
197	greg	1.1	}
198	greg	2.7	return(-1.0);
199	greg	1.1	}
200
201
202	greg	1.17	viewloc(ip, v, p) /* find image location for point */
203			FVECT ip;
204	greg	1.3	register VIEW *v;
205			FVECT p;
206			{
207	gregl	2.13	double d, d2;
208	greg	1.3	FVECT disp;
209	greg	1.5
210	greg	1.3	disp[0] = p[0] - v->vp[0];
211			disp[1] = p[1] - v->vp[1];
212			disp[2] = p[2] - v->vp[2];
213
214	greg	1.12	switch (v->type) {
215			case VT_PAR: /* parallel view */
216	greg	2.7	ip[2] = DOT(disp,v->vdir) - v->vfore;
217	greg	1.13	break;
218	greg	1.12	case VT_PER: /* perspective view */
219	greg	1.11	d = DOT(disp,v->vdir);
220	gregl	2.13	ip[2] = VLEN(disp);
221	greg	1.17	if (d < 0.0) { /* fold pyramid */
222			ip[2] = -ip[2];
223	greg	1.11	d = -d;
224	greg	2.7	}
225			if (d > FTINY) {
226	greg	1.11	d = 1.0/d;
227			disp[0] *= d;
228			disp[1] *= d;
229			disp[2] *= d;
230			}
231	greg	2.7	ip[2] = (1.0 - v->vfored);
232	greg	1.13	break;
233	greg	1.12	case VT_HEM: /* hemispherical fisheye */
234			d = normalize(disp);
235	greg	1.17	if (DOT(disp,v->vdir) < 0.0)
236			ip[2] = -d;
237			else
238			ip[2] = d;
239	greg	2.7	ip[2] -= v->vfore;
240	greg	1.13	break;
241	greg	2.9	case VT_CYL: /* cylindrical panorama */
242			d = DOT(disp,v->hvec);
243	gregl	2.13	d2 = DOT(disp,v->vdir);
244			ip[0] = 180.0/PI * atan2(d,d2) / v->horiz + 0.5 - v->hoff;
245			d = 1.0/sqrt(dd + d2d2);
246			ip[1] = DOT(disp,v->vvec)*d/v->vn2 + 0.5 - v->voff;
247			ip[2] = VLEN(disp);
248	gwlarson	2.15	ip[2] = (1.0 - v->vfored);
249	greg	2.9	return;
250	greg	1.12	case VT_ANG: /* angular fisheye */
251	greg	1.17	ip[0] = 0.5 - v->hoff;
252			ip[1] = 0.5 - v->voff;
253	greg	2.7	ip[2] = normalize(disp) - v->vfore;
254	greg	1.12	d = DOT(disp,v->vdir);
255			if (d >= 1.0-FTINY)
256			return;
257			if (d <= -(1.0-FTINY)) {
258	greg	2.7	ip[0] += 180.0/v->horiz;
259	greg	1.12	return;
260			}
261			d = acos(d)/PI / sqrt(1.0 - d*d);
262	greg	1.17	ip[0] += DOT(disp,v->hvec)d180.0/v->horiz;
263			ip[1] += DOT(disp,v->vvec)d180.0/v->vert;
264	greg	1.12	return;
265	greg	1.3	}
266	greg	1.17	ip[0] = DOT(disp,v->hvec)/v->hn2 + 0.5 - v->hoff;
267			ip[1] = DOT(disp,v->vvec)/v->vn2 + 0.5 - v->voff;
268	greg	1.3	}
269
270
271	greg	1.17	pix2loc(loc, rp, px, py) /* compute image location from pixel pos. */
272			FLOAT loc[2];
273			register RESOLU *rp;
274			int px, py;
275			{
276			register int x, y;
277
278			if (rp->or & YMAJOR) {
279			x = px;
280			y = py;
281			} else {
282			x = py;
283			y = px;
284			}
285			if (rp->or & XDECR)
286			x = rp->xr-1 - x;
287			if (rp->or & YDECR)
288			y = rp->yr-1 - y;
289			loc[0] = (x+.5)/rp->xr;
290			loc[1] = (y+.5)/rp->yr;
291			}
292
293
294			loc2pix(pp, rp, lx, ly) /* compute pixel pos. from image location */
295			int pp[2];
296			register RESOLU *rp;
297			double lx, ly;
298			{
299			register int x, y;
300
301			x = lx * rp->xr;
302			y = ly * rp->yr;
303			if (rp->or & XDECR)
304			x = rp->xr-1 - x;
305			if (rp->or & YDECR)
306			y = rp->yr-1 - y;
307			if (rp->or & YMAJOR) {
308			pp[0] = x;
309			pp[1] = y;
310			} else {
311			pp[0] = y;
312			pp[1] = x;
313			}
314			}
315
316
317	greg	1.5	int
318			getviewopt(v, ac, av) /* process view argument */
319			register VIEW *v;
320			int ac;
321			register char *av[];
322			{
323	greg	1.16	#define check(c,l) if ((av[0][c]&&av[0][c]!=' ') \|\| \
324			badarg(ac-1,av+1,l)) return(-1)
325	greg	1.5
326	greg	1.9	if (ac <= 0 \|\| av[0][0] != '-' \|\| av[0][1] != 'v')
327	greg	1.5	return(-1);
328			switch (av[0][2]) {
329			case 't': /* type */
330			if (!av[0][3] \|\| av[0][3]==' ')
331			return(-1);
332	greg	1.16	check(4,"");
333	greg	1.5	v->type = av[0][3];
334			return(0);
335			case 'p': /* point */
336	greg	1.16	check(3,"fff");
337	greg	1.5	v->vp[0] = atof(av[1]);
338			v->vp[1] = atof(av[2]);
339			v->vp[2] = atof(av[3]);
340			return(3);
341			case 'd': /* direction */
342	greg	1.16	check(3,"fff");
343	greg	1.5	v->vdir[0] = atof(av[1]);
344			v->vdir[1] = atof(av[2]);
345			v->vdir[2] = atof(av[3]);
346			return(3);
347			case 'u': /* up */
348	greg	1.16	check(3,"fff");
349	greg	1.5	v->vup[0] = atof(av[1]);
350			v->vup[1] = atof(av[2]);
351			v->vup[2] = atof(av[3]);
352			return(3);
353			case 'h': /* horizontal size */
354	greg	1.16	check(3,"f");
355	greg	1.5	v->horiz = atof(av[1]);
356			return(1);
357			case 'v': /* vertical size */
358	greg	1.16	check(3,"f");
359	greg	1.5	v->vert = atof(av[1]);
360			return(1);
361	greg	2.7	case 'o': /* fore clipping plane */
362			check(3,"f");
363			v->vfore = atof(av[1]);
364			return(1);
365			case 'a': /* aft clipping plane */
366			check(3,"f");
367			v->vaft = atof(av[1]);
368			return(1);
369	greg	1.5	case 's': /* shift */
370	greg	1.16	check(3,"f");
371	greg	1.5	v->hoff = atof(av[1]);
372			return(1);
373			case 'l': /* lift */
374	greg	1.16	check(3,"f");
375	greg	1.5	v->voff = atof(av[1]);
376			return(1);
377			default:
378			return(-1);
379			}
380			#undef check
381			}
382
383
384			int
385			sscanview(vp, s) /* get view parameters from string */
386			VIEW *vp;
387	greg	1.1	register char *s;
388			{
389	greg	1.5	int ac;
390			char *av[4];
391			int na;
392			int nvopts = 0;
393
394	greg	2.3	if (*s != '-')
395	greg	2.12	s = sskip2(s,1);
396	greg	1.9	while (*s) {
397	greg	1.5	ac = 0;
398			do {
399			av[ac++] = s;
400			while (s && s != ' ')
401			s++;
402			while (*s == ' ')
403			s++;
404			} while (*s && ac < 4);
405			if ((na = getviewopt(vp, ac, av)) >= 0) {
406			if (na+1 < ac)
407			s = av[na+1];
408			nvopts++;
409	greg	1.9	} else if (ac > 1)
410			s = av[1];
411			}
412	greg	1.5	return(nvopts);
413	greg	1.1	}
414
415
416			fprintview(vp, fp) /* write out view parameters */
417			register VIEW *vp;
418			FILE *fp;
419			{
420			fprintf(fp, " -vt%c", vp->type);
421			fprintf(fp, " -vp %.6g %.6g %.6g", vp->vp[0], vp->vp[1], vp->vp[2]);
422			fprintf(fp, " -vd %.6g %.6g %.6g", vp->vdir[0], vp->vdir[1], vp->vdir[2]);
423			fprintf(fp, " -vu %.6g %.6g %.6g", vp->vup[0], vp->vup[1], vp->vup[2]);
424			fprintf(fp, " -vh %.6g -vv %.6g", vp->horiz, vp->vert);
425	greg	2.7	fprintf(fp, " -vo %.6g -va %.6g", vp->vfore, vp->vaft);
426	greg	1.9	fprintf(fp, " -vs %.6g -vl %.6g", vp->hoff, vp->voff);
427	greg	2.11	}
428
429
430			char *
431			viewopt(vp) /* translate to minimal view string */
432			register VIEW *vp;
433			{
434			static char vwstr[128];
435			register char *cp = vwstr;
436
437			if (vp->type != stdview.type) {
438			sprintf(cp, " -vt%c", vp->type);
439			cp += strlen(cp);
440			}
441			if (!VEQ(vp->vp,stdview.vp)) {
442			sprintf(cp, " -vp %.6g %.6g %.6g",
443			vp->vp[0], vp->vp[1], vp->vp[2]);
444			cp += strlen(cp);
445			}
446			if (!VEQ(vp->vdir,stdview.vdir)) {
447			sprintf(cp, " -vd %.6g %.6g %.6g",
448			vp->vdir[0], vp->vdir[1], vp->vdir[2]);
449			cp += strlen(cp);
450			}
451			if (!VEQ(vp->vup,stdview.vup)) {
452			sprintf(cp, " -vu %.6g %.6g %.6g",
453			vp->vup[0], vp->vup[1], vp->vup[2]);
454			cp += strlen(cp);
455			}
456			if (!FEQ(vp->horiz,stdview.horiz)) {
457			sprintf(cp, " -vh %.6g", vp->horiz);
458			cp += strlen(cp);
459			}
460			if (!FEQ(vp->vert,stdview.vert)) {
461			sprintf(cp, " -vv %.6g", vp->vert);
462			cp += strlen(cp);
463			}
464			if (!FEQ(vp->vfore,stdview.vfore)) {
465			sprintf(cp, " -vo %.6g", vp->vfore);
466			cp += strlen(cp);
467			}
468			if (!FEQ(vp->vaft,stdview.vaft)) {
469			sprintf(cp, " -va %.6g", vp->vaft);
470			cp += strlen(cp);
471			}
472			if (!FEQ(vp->hoff,stdview.hoff)) {
473			sprintf(cp, " -vs %.6g", vp->hoff);
474			cp += strlen(cp);
475			}
476			if (!FEQ(vp->voff,stdview.voff)) {
477			sprintf(cp, " -vl %.6g", vp->voff);
478			cp += strlen(cp);
479			}
480			return(vwstr);
481	greg	1.1	}
482
483
484	greg	2.3	int
485			isview(s) /* is this a view string? */
486			char *s;
487			{
488	greg	2.5	static char *altname[]={NULL,VIEWSTR,"rpict","rview","pinterp",NULL};
489			extern char *progname;
490	greg	2.3	register char *cp;
491			register char **an;
492			/* add program name to list */
493	greg	2.5	if (altname[0] == NULL) {
494			for (cp = progname; *cp; cp++)
495			;
496			while (cp > progname && !ISDIRSEP(cp[-1]))
497			cp--;
498			altname[0] = cp;
499			}
500	greg	2.3	/* skip leading path */
501			cp = s;
502			while (cp && cp != ' ')
503			cp++;
504	greg	2.5	while (cp > s && !ISDIRSEP(cp[-1]))
505	greg	2.3	cp--;
506			for (an = altname; *an != NULL; an++)
507			if (!strncmp(an, cp, strlen(an)))
508			return(1);
509			return(0);
510			}
511	greg	1.1
512	greg	2.3
513	greg	1.15	struct myview {
514			VIEW *hv;
515			int ok;
516			};
517	greg	1.1
518	greg	1.15
519	gwlarson	2.14	static int
520	greg	1.15	gethview(s, v) /* get view from header */
521	greg	1.1	char *s;
522	greg	1.15	register struct myview *v;
523	greg	1.1	{
524	greg	2.3	if (isview(s) && sscanview(v->hv, s) > 0)
525			v->ok++;
526	gwlarson	2.14	return(0);
527	greg	1.1	}
528
529
530			int
531	greg	1.17	viewfile(fname, vp, rp) /* get view from file */
532	greg	1.1	char *fname;
533			VIEW *vp;
534	greg	1.17	RESOLU *rp;
535	greg	1.1	{
536	greg	1.15	struct myview mvs;
537	greg	1.1	FILE *fp;
538
539			if ((fp = fopen(fname, "r")) == NULL)
540			return(-1);
541
542	greg	1.15	mvs.hv = vp;
543			mvs.ok = 0;
544	greg	1.1
545	greg	1.15	getheader(fp, gethview, &mvs);
546	greg	1.8
547	greg	1.17	if (rp != NULL && !fgetsresolu(rp, fp))
548	greg	1.15	mvs.ok = 0;
549	greg	1.1
550			fclose(fp);
551
552	greg	1.15	return(mvs.ok);
553	greg	1.1	}