src/common/image.c

#ifndef lint
static const char       RCSid[] = "$Id: image.c,v 2.26 2004/01/02 11:36:26 schorsch Exp $";
#endif
/*
 *  image.c - routines for image generation.
 *
 *  External symbols declared in view.h
 */

#include "copyright.h"

#include  "rtio.h"
#include  "paths.h"
#include  "view.h"


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

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

static gethfunc gethview;


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

        if (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","rvu","rpiece","pinterp",NULL};
        extern char  *progname;
        register char  *cp;
        register char  **an;
                                        /* add program name to list */
        if (altname[0] == NULL) {
                for (cp = progname; *cp; cp++)
                        ;
                while (cp > progname && !ISDIRSEP(cp[-1]))
                        cp--;
                altname[0] = cp;
        }
                                        /* skip leading path */
        cp = s;
        while (*cp && *cp != ' ')
                cp++;
        while (cp > s && !ISDIRSEP(cp[-1]))
                cp--;
        for (an = altname; *an != NULL; an++)
                if (!strncmp(*an, cp, strlen(*an)))
                        return(1);
        return(0);
}


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


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


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

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

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

        getheader(fp, gethview, &mvs);

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

        fclose(fp);

        return(mvs.ok);
}
Revision:	2.27
Committed:	Thu Feb 12 18:55:50 2004 UTC (20 years, 2 months ago) by greg
Content type:	text/plain
Branch:	MAIN
Changes since 2.26:	+2 -1 lines
Log Message:	Moved paths.h out of rtio.h and included it manually where R_OK was needed
#	User	Rev	Content
1	greg	1.1	#ifndef lint
2	greg	2.27	static const char RCSid[] = "$Id: image.c,v 2.26 2004/01/02 11:36:26 schorsch 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	schorsch	2.22	#include "rtio.h"
13	greg	2.27	#include "paths.h"
14	greg	1.1	#include "view.h"
15
16	greg	2.4
17	greg	2.11	#define FEQ(x,y) (fabs((x)-(y)) <= FTINY)
18			#define VEQ(v,w) (FEQ((v)[0],(w)[0]) && FEQ((v)[1],(w)[1]) \
19			&& FEQ((v)[2],(w)[2]))
20
21	greg	1.5	VIEW stdview = STDVIEW; /* default view parameters */
22	greg	1.1
23	schorsch	2.26	static gethfunc gethview;
24
25	greg	1.1
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	2.16	void
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	2.16	void
204	greg	1.17	viewloc(ip, v, p) /* find image location for point */
205			FVECT ip;
206	greg	1.3	register VIEW *v;
207			FVECT p;
208			{
209	gregl	2.13	double d, d2;
210	greg	1.3	FVECT disp;
211	greg	1.5
212	greg	1.3	disp[0] = p[0] - v->vp[0];
213			disp[1] = p[1] - v->vp[1];
214			disp[2] = p[2] - v->vp[2];
215
216	greg	1.12	switch (v->type) {
217			case VT_PAR: /* parallel view */
218	greg	2.7	ip[2] = DOT(disp,v->vdir) - v->vfore;
219	greg	1.13	break;
220	greg	1.12	case VT_PER: /* perspective view */
221	greg	1.11	d = DOT(disp,v->vdir);
222	gregl	2.13	ip[2] = VLEN(disp);
223	greg	1.17	if (d < 0.0) { /* fold pyramid */
224			ip[2] = -ip[2];
225	greg	1.11	d = -d;
226	greg	2.7	}
227			if (d > FTINY) {
228	greg	1.11	d = 1.0/d;
229			disp[0] *= d;
230			disp[1] *= d;
231			disp[2] *= d;
232			}
233	greg	2.7	ip[2] = (1.0 - v->vfored);
234	greg	1.13	break;
235	greg	1.12	case VT_HEM: /* hemispherical fisheye */
236			d = normalize(disp);
237	greg	1.17	if (DOT(disp,v->vdir) < 0.0)
238			ip[2] = -d;
239			else
240			ip[2] = d;
241	greg	2.7	ip[2] -= v->vfore;
242	greg	1.13	break;
243	greg	2.9	case VT_CYL: /* cylindrical panorama */
244			d = DOT(disp,v->hvec);
245	gregl	2.13	d2 = DOT(disp,v->vdir);
246			ip[0] = 180.0/PI * atan2(d,d2) / v->horiz + 0.5 - v->hoff;
247			d = 1.0/sqrt(dd + d2d2);
248			ip[1] = DOT(disp,v->vvec)*d/v->vn2 + 0.5 - v->voff;
249			ip[2] = VLEN(disp);
250	gwlarson	2.15	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	2.16	void
274	greg	1.17	pix2loc(loc, rp, px, py) /* compute image location from pixel pos. */
275	schorsch	2.18	RREAL loc[2];
276	greg	1.17	register RESOLU *rp;
277			int px, py;
278			{
279			register int x, y;
280
281	greg	2.16	if (rp->rt & YMAJOR) {
282	greg	1.17	x = px;
283			y = py;
284			} else {
285			x = py;
286			y = px;
287			}
288	greg	2.16	if (rp->rt & XDECR)
289	greg	1.17	x = rp->xr-1 - x;
290	greg	2.16	if (rp->rt & YDECR)
291	greg	1.17	y = rp->yr-1 - y;
292			loc[0] = (x+.5)/rp->xr;
293			loc[1] = (y+.5)/rp->yr;
294			}
295
296
297	greg	2.16	void
298	greg	1.17	loc2pix(pp, rp, lx, ly) /* compute pixel pos. from image location */
299			int pp[2];
300			register RESOLU *rp;
301			double lx, ly;
302			{
303			register int x, y;
304
305			x = lx * rp->xr;
306			y = ly * rp->yr;
307	greg	2.16	if (rp->rt & XDECR)
308	greg	1.17	x = rp->xr-1 - x;
309	greg	2.16	if (rp->rt & YDECR)
310	greg	1.17	y = rp->yr-1 - y;
311	greg	2.16	if (rp->rt & YMAJOR) {
312	greg	1.17	pp[0] = x;
313			pp[1] = y;
314			} else {
315			pp[0] = y;
316			pp[1] = x;
317			}
318			}
319
320
321	greg	1.5	int
322			getviewopt(v, ac, av) /* process view argument */
323			register VIEW *v;
324			int ac;
325			register char *av[];
326			{
327	greg	1.16	#define check(c,l) if ((av[0][c]&&av[0][c]!=' ') \|\| \
328			badarg(ac-1,av+1,l)) return(-1)
329	greg	1.5
330	greg	1.9	if (ac <= 0 \|\| av[0][0] != '-' \|\| av[0][1] != 'v')
331	greg	1.5	return(-1);
332			switch (av[0][2]) {
333			case 't': /* type */
334			if (!av[0][3] \|\| av[0][3]==' ')
335			return(-1);
336	greg	1.16	check(4,"");
337	greg	1.5	v->type = av[0][3];
338			return(0);
339			case 'p': /* point */
340	greg	1.16	check(3,"fff");
341	greg	1.5	v->vp[0] = atof(av[1]);
342			v->vp[1] = atof(av[2]);
343			v->vp[2] = atof(av[3]);
344			return(3);
345			case 'd': /* direction */
346	greg	1.16	check(3,"fff");
347	greg	1.5	v->vdir[0] = atof(av[1]);
348			v->vdir[1] = atof(av[2]);
349			v->vdir[2] = atof(av[3]);
350			return(3);
351			case 'u': /* up */
352	greg	1.16	check(3,"fff");
353	greg	1.5	v->vup[0] = atof(av[1]);
354			v->vup[1] = atof(av[2]);
355			v->vup[2] = atof(av[3]);
356			return(3);
357			case 'h': /* horizontal size */
358	greg	1.16	check(3,"f");
359	greg	1.5	v->horiz = atof(av[1]);
360			return(1);
361			case 'v': /* vertical size */
362	greg	1.16	check(3,"f");
363	greg	1.5	v->vert = atof(av[1]);
364			return(1);
365	greg	2.7	case 'o': /* fore clipping plane */
366			check(3,"f");
367			v->vfore = atof(av[1]);
368			return(1);
369			case 'a': /* aft clipping plane */
370			check(3,"f");
371			v->vaft = atof(av[1]);
372			return(1);
373	greg	1.5	case 's': /* shift */
374	greg	1.16	check(3,"f");
375	greg	1.5	v->hoff = atof(av[1]);
376			return(1);
377			case 'l': /* lift */
378	greg	1.16	check(3,"f");
379	greg	1.5	v->voff = atof(av[1]);
380			return(1);
381			default:
382			return(-1);
383			}
384			#undef check
385			}
386
387
388			int
389			sscanview(vp, s) /* get view parameters from string */
390			VIEW *vp;
391	greg	1.1	register char *s;
392			{
393	greg	1.5	int ac;
394			char *av[4];
395			int na;
396			int nvopts = 0;
397
398	greg	2.20	while (*s == ' ')
399	greg	2.19	s++;
400	greg	2.20	if (*s != '-')
401			s = sskip2(s,1);
402	greg	1.9	while (*s) {
403	greg	1.5	ac = 0;
404			do {
405	greg	2.21	if (ac \|\| *s == '-')
406			av[ac++] = s;
407	greg	1.5	while (s && s != ' ')
408			s++;
409			while (*s == ' ')
410			s++;
411			} while (*s && ac < 4);
412			if ((na = getviewopt(vp, ac, av)) >= 0) {
413			if (na+1 < ac)
414			s = av[na+1];
415			nvopts++;
416	greg	1.9	} else if (ac > 1)
417			s = av[1];
418			}
419	greg	1.5	return(nvopts);
420	greg	1.1	}
421
422
423	greg	2.16	void
424	greg	1.1	fprintview(vp, fp) /* write out view parameters */
425			register VIEW *vp;
426			FILE *fp;
427			{
428			fprintf(fp, " -vt%c", vp->type);
429			fprintf(fp, " -vp %.6g %.6g %.6g", vp->vp[0], vp->vp[1], vp->vp[2]);
430			fprintf(fp, " -vd %.6g %.6g %.6g", vp->vdir[0], vp->vdir[1], vp->vdir[2]);
431			fprintf(fp, " -vu %.6g %.6g %.6g", vp->vup[0], vp->vup[1], vp->vup[2]);
432			fprintf(fp, " -vh %.6g -vv %.6g", vp->horiz, vp->vert);
433	greg	2.7	fprintf(fp, " -vo %.6g -va %.6g", vp->vfore, vp->vaft);
434	greg	1.9	fprintf(fp, " -vs %.6g -vl %.6g", vp->hoff, vp->voff);
435	greg	2.11	}
436
437
438			char *
439			viewopt(vp) /* translate to minimal view string */
440			register VIEW *vp;
441			{
442			static char vwstr[128];
443			register char *cp = vwstr;
444
445			if (vp->type != stdview.type) {
446			sprintf(cp, " -vt%c", vp->type);
447			cp += strlen(cp);
448			}
449			if (!VEQ(vp->vp,stdview.vp)) {
450			sprintf(cp, " -vp %.6g %.6g %.6g",
451			vp->vp[0], vp->vp[1], vp->vp[2]);
452			cp += strlen(cp);
453			}
454			if (!VEQ(vp->vdir,stdview.vdir)) {
455			sprintf(cp, " -vd %.6g %.6g %.6g",
456			vp->vdir[0], vp->vdir[1], vp->vdir[2]);
457			cp += strlen(cp);
458			}
459			if (!VEQ(vp->vup,stdview.vup)) {
460			sprintf(cp, " -vu %.6g %.6g %.6g",
461			vp->vup[0], vp->vup[1], vp->vup[2]);
462			cp += strlen(cp);
463			}
464			if (!FEQ(vp->horiz,stdview.horiz)) {
465			sprintf(cp, " -vh %.6g", vp->horiz);
466			cp += strlen(cp);
467			}
468			if (!FEQ(vp->vert,stdview.vert)) {
469			sprintf(cp, " -vv %.6g", vp->vert);
470			cp += strlen(cp);
471			}
472			if (!FEQ(vp->vfore,stdview.vfore)) {
473			sprintf(cp, " -vo %.6g", vp->vfore);
474			cp += strlen(cp);
475			}
476			if (!FEQ(vp->vaft,stdview.vaft)) {
477			sprintf(cp, " -va %.6g", vp->vaft);
478			cp += strlen(cp);
479			}
480			if (!FEQ(vp->hoff,stdview.hoff)) {
481			sprintf(cp, " -vs %.6g", vp->hoff);
482			cp += strlen(cp);
483			}
484			if (!FEQ(vp->voff,stdview.voff)) {
485			sprintf(cp, " -vl %.6g", vp->voff);
486			cp += strlen(cp);
487			}
488			return(vwstr);
489	greg	1.1	}
490
491
492	greg	2.3	int
493			isview(s) /* is this a view string? */
494			char *s;
495			{
496	greg	2.25	static char *altname[]={NULL,VIEWSTR,"rpict","rview","rvu","rpiece","pinterp",NULL};
497	greg	2.5	extern char *progname;
498	greg	2.3	register char *cp;
499			register char **an;
500			/* add program name to list */
501	greg	2.5	if (altname[0] == NULL) {
502			for (cp = progname; *cp; cp++)
503			;
504			while (cp > progname && !ISDIRSEP(cp[-1]))
505			cp--;
506			altname[0] = cp;
507			}
508	greg	2.3	/* skip leading path */
509			cp = s;
510			while (cp && cp != ' ')
511			cp++;
512	greg	2.5	while (cp > s && !ISDIRSEP(cp[-1]))
513	greg	2.3	cp--;
514			for (an = altname; *an != NULL; an++)
515			if (!strncmp(an, cp, strlen(an)))
516			return(1);
517			return(0);
518			}
519	greg	1.1
520	greg	2.3
521	greg	1.15	struct myview {
522			VIEW *hv;
523			int ok;
524			};
525	greg	1.1
526	greg	1.15
527	gwlarson	2.14	static int
528	schorsch	2.26	gethview( /* get view from header */
529			char *s,
530			void *v
531			)
532	greg	1.1	{
533	schorsch	2.26	if (isview(s) && sscanview(((struct myview*)v)->hv, s) > 0)
534			((struct myview*)v)->ok++;
535	gwlarson	2.14	return(0);
536	greg	1.1	}
537
538
539			int
540	greg	1.17	viewfile(fname, vp, rp) /* get view from file */
541	greg	1.1	char *fname;
542			VIEW *vp;
543	greg	1.17	RESOLU *rp;
544	greg	1.1	{
545	greg	1.15	struct myview mvs;
546	greg	1.1	FILE *fp;
547
548	greg	2.16	if (fname == NULL \|\| !strcmp(fname, "-"))
549			fp = stdin;
550			else if ((fp = fopen(fname, "r")) == NULL)
551	greg	1.1	return(-1);
552
553	greg	1.15	mvs.hv = vp;
554			mvs.ok = 0;
555	greg	1.1
556	schorsch	2.26	getheader(fp, gethview, &mvs);
557	greg	1.8
558	greg	1.17	if (rp != NULL && !fgetsresolu(rp, fp))
559	greg	1.15	mvs.ok = 0;
560	greg	1.1
561			fclose(fp);
562
563	greg	1.15	return(mvs.ok);
564	greg	1.1	}