src/common/image.c

#ifndef lint
static const char       RCSid[] = "$Id: image.c,v 2.20 2003/08/29 23:03:13 greg Exp $";
#endif
/*
 *  image.c - routines for image generation.
 *
 *  External symbols declared in view.h
 */

#include "copyright.h"

#include  "standard.h"

#include  "view.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);
}


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 *= 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);
}


void
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;
}


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


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

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

        getheader(fp, (int (*)(char *, char *))&gethview, (char *)&mvs);

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

        fclose(fp);

        return(mvs.ok);
}
Revision:	2.21
Committed:	Sun Sep 7 05:32:02 2003 UTC (20 years, 7 months ago) by greg
Content type:	text/plain
Branch:	MAIN
Changes since 2.20:	+3 -2 lines
Log Message:	Prototype fix
#	User	Rev	Content
1	greg	1.1	#ifndef lint
2	greg	2.21	static const char RCSid[] = "$Id: image.c,v 2.20 2003/08/29 23:03:13 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			#include "standard.h"
13
14			#include "view.h"
15
16	greg	2.4	#include "paths.h"
17
18	greg	2.11	#define FEQ(x,y) (fabs((x)-(y)) <= FTINY)
19			#define VEQ(v,w) (FEQ((v)[0],(w)[0]) && FEQ((v)[1],(w)[1]) \
20			&& FEQ((v)[2],(w)[2]))
21
22	greg	1.5	VIEW stdview = STDVIEW; /* default view parameters */
23	greg	1.1
24
25			char *
26	greg	1.5	setview(v) /* set hvec and vvec, return message on error */
27			register VIEW *v;
28	greg	1.3	{
29	greg	1.12	static char ill_horiz[] = "illegal horizontal view size";
30			static char ill_vert[] = "illegal vertical view size";
31
32	gwlarson	2.15	if (v->vaft < -FTINY \|\| (v->vaft > FTINY && v->vaft <= v->vfore))
33	greg	2.7	return("illegal fore/aft clipping plane");
34
35	greg	1.1	if (normalize(v->vdir) == 0.0) /* normalize direction */
36			return("zero view direction");
37
38	greg	1.14	if (normalize(v->vup) == 0.0) /* normalize view up */
39			return("zero view up vector");
40
41	greg	1.5	fcross(v->hvec, v->vdir, v->vup); /* compute horiz dir */
42
43			if (normalize(v->hvec) == 0.0)
44	greg	1.14	return("view up parallel to view direction");
45	greg	1.1
46	greg	1.5	fcross(v->vvec, v->hvec, v->vdir); /* compute vert dir */
47
48	greg	1.12	if (v->horiz <= FTINY)
49			return(ill_horiz);
50			if (v->vert <= FTINY)
51			return(ill_vert);
52
53			switch (v->type) {
54			case VT_PAR: /* parallel view */
55	greg	1.5	v->hn2 = v->horiz;
56	greg	1.12	v->vn2 = v->vert;
57			break;
58			case VT_PER: /* perspective view */
59			if (v->horiz >= 180.0-FTINY)
60			return(ill_horiz);
61			if (v->vert >= 180.0-FTINY)
62			return(ill_vert);
63	greg	1.5	v->hn2 = 2.0 * tan(v->horiz*(PI/180.0/2.0));
64	greg	1.12	v->vn2 = 2.0 * tan(v->vert*(PI/180.0/2.0));
65			break;
66	greg	2.9	case VT_CYL: /* cylindrical panorama */
67			if (v->horiz > 360.0+FTINY)
68			return(ill_horiz);
69			if (v->vert >= 180.0-FTINY)
70			return(ill_vert);
71			v->hn2 = v->horiz * (PI/180.0);
72			v->vn2 = 2.0 * tan(v->vert*(PI/180.0/2.0));
73			break;
74	greg	1.12	case VT_ANG: /* angular fisheye */
75			if (v->horiz > 360.0+FTINY)
76			return(ill_horiz);
77			if (v->vert > 360.0+FTINY)
78			return(ill_vert);
79	greg	2.9	v->hn2 = v->horiz * (PI/180.0);
80			v->vn2 = v->vert * (PI/180.0);
81	greg	1.12	break;
82			case VT_HEM: /* hemispherical fisheye */
83			if (v->horiz > 180.0+FTINY)
84			return(ill_horiz);
85			if (v->vert > 180.0+FTINY)
86			return(ill_vert);
87			v->hn2 = 2.0 * sin(v->horiz*(PI/180.0/2.0));
88			v->vn2 = 2.0 * sin(v->vert*(PI/180.0/2.0));
89			break;
90			default:
91	greg	1.1	return("unknown view type");
92	greg	1.12	}
93	greg	1.13	if (v->type != VT_ANG) {
94	greg	2.9	if (v->type != VT_CYL) {
95			v->hvec[0] *= v->hn2;
96			v->hvec[1] *= v->hn2;
97			v->hvec[2] *= v->hn2;
98			}
99	greg	1.12	v->vvec[0] *= v->vn2;
100			v->vvec[1] *= v->vn2;
101			v->vvec[2] *= v->vn2;
102			}
103	greg	1.5	v->hn2 *= v->hn2;
104			v->vn2 *= v->vn2;
105	greg	1.1
106			return(NULL);
107			}
108
109
110	greg	2.16	void
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	2.16	void
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	gwlarson	2.15	ip[2] = (1.0 - v->vfored);
250	greg	2.9	return;
251	greg	1.12	case VT_ANG: /* angular fisheye */
252	greg	1.17	ip[0] = 0.5 - v->hoff;
253			ip[1] = 0.5 - v->voff;
254	greg	2.7	ip[2] = normalize(disp) - v->vfore;
255	greg	1.12	d = DOT(disp,v->vdir);
256			if (d >= 1.0-FTINY)
257			return;
258			if (d <= -(1.0-FTINY)) {
259	greg	2.7	ip[0] += 180.0/v->horiz;
260	greg	1.12	return;
261			}
262			d = acos(d)/PI / sqrt(1.0 - d*d);
263	greg	1.17	ip[0] += DOT(disp,v->hvec)d180.0/v->horiz;
264			ip[1] += DOT(disp,v->vvec)d180.0/v->vert;
265	greg	1.12	return;
266	greg	1.3	}
267	greg	1.17	ip[0] = DOT(disp,v->hvec)/v->hn2 + 0.5 - v->hoff;
268			ip[1] = DOT(disp,v->vvec)/v->vn2 + 0.5 - v->voff;
269	greg	1.3	}
270
271
272	greg	2.16	void
273	greg	1.17	pix2loc(loc, rp, px, py) /* compute image location from pixel pos. */
274	schorsch	2.18	RREAL loc[2];
275	greg	1.17	register RESOLU *rp;
276			int px, py;
277			{
278			register int x, y;
279
280	greg	2.16	if (rp->rt & YMAJOR) {
281	greg	1.17	x = px;
282			y = py;
283			} else {
284			x = py;
285			y = px;
286			}
287	greg	2.16	if (rp->rt & XDECR)
288	greg	1.17	x = rp->xr-1 - x;
289	greg	2.16	if (rp->rt & YDECR)
290	greg	1.17	y = rp->yr-1 - y;
291			loc[0] = (x+.5)/rp->xr;
292			loc[1] = (y+.5)/rp->yr;
293			}
294
295
296	greg	2.16	void
297	greg	1.17	loc2pix(pp, rp, lx, ly) /* compute pixel pos. from image location */
298			int pp[2];
299			register RESOLU *rp;
300			double lx, ly;
301			{
302			register int x, y;
303
304			x = lx * rp->xr;
305			y = ly * rp->yr;
306	greg	2.16	if (rp->rt & XDECR)
307	greg	1.17	x = rp->xr-1 - x;
308	greg	2.16	if (rp->rt & YDECR)
309	greg	1.17	y = rp->yr-1 - y;
310	greg	2.16	if (rp->rt & YMAJOR) {
311	greg	1.17	pp[0] = x;
312			pp[1] = y;
313			} else {
314			pp[0] = y;
315			pp[1] = x;
316			}
317			}
318
319
320	greg	1.5	int
321			getviewopt(v, ac, av) /* process view argument */
322			register VIEW *v;
323			int ac;
324			register char *av[];
325			{
326	greg	1.16	#define check(c,l) if ((av[0][c]&&av[0][c]!=' ') \|\| \
327			badarg(ac-1,av+1,l)) return(-1)
328	greg	1.5
329	greg	1.9	if (ac <= 0 \|\| av[0][0] != '-' \|\| av[0][1] != 'v')
330	greg	1.5	return(-1);
331			switch (av[0][2]) {
332			case 't': /* type */
333			if (!av[0][3] \|\| av[0][3]==' ')
334			return(-1);
335	greg	1.16	check(4,"");
336	greg	1.5	v->type = av[0][3];
337			return(0);
338			case 'p': /* point */
339	greg	1.16	check(3,"fff");
340	greg	1.5	v->vp[0] = atof(av[1]);
341			v->vp[1] = atof(av[2]);
342			v->vp[2] = atof(av[3]);
343			return(3);
344			case 'd': /* direction */
345	greg	1.16	check(3,"fff");
346	greg	1.5	v->vdir[0] = atof(av[1]);
347			v->vdir[1] = atof(av[2]);
348			v->vdir[2] = atof(av[3]);
349			return(3);
350			case 'u': /* up */
351	greg	1.16	check(3,"fff");
352	greg	1.5	v->vup[0] = atof(av[1]);
353			v->vup[1] = atof(av[2]);
354			v->vup[2] = atof(av[3]);
355			return(3);
356			case 'h': /* horizontal size */
357	greg	1.16	check(3,"f");
358	greg	1.5	v->horiz = atof(av[1]);
359			return(1);
360			case 'v': /* vertical size */
361	greg	1.16	check(3,"f");
362	greg	1.5	v->vert = atof(av[1]);
363			return(1);
364	greg	2.7	case 'o': /* fore clipping plane */
365			check(3,"f");
366			v->vfore = atof(av[1]);
367			return(1);
368			case 'a': /* aft clipping plane */
369			check(3,"f");
370			v->vaft = atof(av[1]);
371			return(1);
372	greg	1.5	case 's': /* shift */
373	greg	1.16	check(3,"f");
374	greg	1.5	v->hoff = atof(av[1]);
375			return(1);
376			case 'l': /* lift */
377	greg	1.16	check(3,"f");
378	greg	1.5	v->voff = atof(av[1]);
379			return(1);
380			default:
381			return(-1);
382			}
383			#undef check
384			}
385
386
387			int
388			sscanview(vp, s) /* get view parameters from string */
389			VIEW *vp;
390	greg	1.1	register char *s;
391			{
392	greg	1.5	int ac;
393			char *av[4];
394			int na;
395			int nvopts = 0;
396
397	greg	2.20	while (*s == ' ')
398	greg	2.19	s++;
399	greg	2.20	if (*s != '-')
400			s = sskip2(s,1);
401	greg	1.9	while (*s) {
402	greg	1.5	ac = 0;
403			do {
404	greg	2.21	if (ac \|\| *s == '-')
405			av[ac++] = s;
406	greg	1.5	while (s && s != ' ')
407			s++;
408			while (*s == ' ')
409			s++;
410			} while (*s && ac < 4);
411			if ((na = getviewopt(vp, ac, av)) >= 0) {
412			if (na+1 < ac)
413			s = av[na+1];
414			nvopts++;
415	greg	1.9	} else if (ac > 1)
416			s = av[1];
417			}
418	greg	1.5	return(nvopts);
419	greg	1.1	}
420
421
422	greg	2.16	void
423	greg	1.1	fprintview(vp, fp) /* write out view parameters */
424			register VIEW *vp;
425			FILE *fp;
426			{
427			fprintf(fp, " -vt%c", vp->type);
428			fprintf(fp, " -vp %.6g %.6g %.6g", vp->vp[0], vp->vp[1], vp->vp[2]);
429			fprintf(fp, " -vd %.6g %.6g %.6g", vp->vdir[0], vp->vdir[1], vp->vdir[2]);
430			fprintf(fp, " -vu %.6g %.6g %.6g", vp->vup[0], vp->vup[1], vp->vup[2]);
431			fprintf(fp, " -vh %.6g -vv %.6g", vp->horiz, vp->vert);
432	greg	2.7	fprintf(fp, " -vo %.6g -va %.6g", vp->vfore, vp->vaft);
433	greg	1.9	fprintf(fp, " -vs %.6g -vl %.6g", vp->hoff, vp->voff);
434	greg	2.11	}
435
436
437			char *
438			viewopt(vp) /* translate to minimal view string */
439			register VIEW *vp;
440			{
441			static char vwstr[128];
442			register char *cp = vwstr;
443
444			if (vp->type != stdview.type) {
445			sprintf(cp, " -vt%c", vp->type);
446			cp += strlen(cp);
447			}
448			if (!VEQ(vp->vp,stdview.vp)) {
449			sprintf(cp, " -vp %.6g %.6g %.6g",
450			vp->vp[0], vp->vp[1], vp->vp[2]);
451			cp += strlen(cp);
452			}
453			if (!VEQ(vp->vdir,stdview.vdir)) {
454			sprintf(cp, " -vd %.6g %.6g %.6g",
455			vp->vdir[0], vp->vdir[1], vp->vdir[2]);
456			cp += strlen(cp);
457			}
458			if (!VEQ(vp->vup,stdview.vup)) {
459			sprintf(cp, " -vu %.6g %.6g %.6g",
460			vp->vup[0], vp->vup[1], vp->vup[2]);
461			cp += strlen(cp);
462			}
463			if (!FEQ(vp->horiz,stdview.horiz)) {
464			sprintf(cp, " -vh %.6g", vp->horiz);
465			cp += strlen(cp);
466			}
467			if (!FEQ(vp->vert,stdview.vert)) {
468			sprintf(cp, " -vv %.6g", vp->vert);
469			cp += strlen(cp);
470			}
471			if (!FEQ(vp->vfore,stdview.vfore)) {
472			sprintf(cp, " -vo %.6g", vp->vfore);
473			cp += strlen(cp);
474			}
475			if (!FEQ(vp->vaft,stdview.vaft)) {
476			sprintf(cp, " -va %.6g", vp->vaft);
477			cp += strlen(cp);
478			}
479			if (!FEQ(vp->hoff,stdview.hoff)) {
480			sprintf(cp, " -vs %.6g", vp->hoff);
481			cp += strlen(cp);
482			}
483			if (!FEQ(vp->voff,stdview.voff)) {
484			sprintf(cp, " -vl %.6g", vp->voff);
485			cp += strlen(cp);
486			}
487			return(vwstr);
488	greg	1.1	}
489
490
491	greg	2.3	int
492			isview(s) /* is this a view string? */
493			char *s;
494			{
495	greg	2.5	static char *altname[]={NULL,VIEWSTR,"rpict","rview","pinterp",NULL};
496			extern char *progname;
497	greg	2.3	register char *cp;
498			register char **an;
499			/* add program name to list */
500	greg	2.5	if (altname[0] == NULL) {
501			for (cp = progname; *cp; cp++)
502			;
503			while (cp > progname && !ISDIRSEP(cp[-1]))
504			cp--;
505			altname[0] = cp;
506			}
507	greg	2.3	/* skip leading path */
508			cp = s;
509			while (cp && cp != ' ')
510			cp++;
511	greg	2.5	while (cp > s && !ISDIRSEP(cp[-1]))
512	greg	2.3	cp--;
513			for (an = altname; *an != NULL; an++)
514			if (!strncmp(an, cp, strlen(an)))
515			return(1);
516			return(0);
517			}
518	greg	1.1
519	greg	2.3
520	greg	1.15	struct myview {
521			VIEW *hv;
522			int ok;
523			};
524	greg	1.1
525	greg	1.15
526	gwlarson	2.14	static int
527	greg	1.15	gethview(s, v) /* get view from header */
528	greg	1.1	char *s;
529	greg	1.15	register struct myview *v;
530	greg	1.1	{
531	greg	2.3	if (isview(s) && sscanview(v->hv, s) > 0)
532			v->ok++;
533	gwlarson	2.14	return(0);
534	greg	1.1	}
535
536
537			int
538	greg	1.17	viewfile(fname, vp, rp) /* get view from file */
539	greg	1.1	char *fname;
540			VIEW *vp;
541	greg	1.17	RESOLU *rp;
542	greg	1.1	{
543	greg	1.15	struct myview mvs;
544	greg	1.1	FILE *fp;
545
546	greg	2.16	if (fname == NULL \|\| !strcmp(fname, "-"))
547			fp = stdin;
548			else if ((fp = fopen(fname, "r")) == NULL)
549	greg	1.1	return(-1);
550
551	greg	1.15	mvs.hv = vp;
552			mvs.ok = 0;
553	greg	1.1
554	greg	2.16	getheader(fp, (int ()(char , char ))&gethview, (char )&mvs);
555	greg	1.8
556	greg	1.17	if (rp != NULL && !fgetsresolu(rp, fp))
557	greg	1.15	mvs.ok = 0;
558	greg	1.1
559			fclose(fp);
560
561	greg	1.15	return(mvs.ok);
562	greg	1.1	}