src/common/image.c

#ifndef lint
static const char       RCSid[] = "$Id: image.c,v 2.27 2004/02/12 18:55:50 greg Exp $";
#endif
/*
 *  image.c - routines for image generation.
 *
 *  External symbols declared in view.h
 */

#include "copyright.h"

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


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

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

static gethfunc gethview;


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

        if (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:	2.28
Committed:	Tue Jun 8 19:48:29 2004 UTC (19 years, 10 months ago) by greg
Content type:	text/plain
Branch:	MAIN
CVS Tags:	rad3R6, rad3R6P1
Changes since 2.27:	+2 -1 lines
Log Message:	Removed redundant #include's and fixed ordering on some headers
#	User	Rev	Content
1	greg	1.1	#ifndef lint
2	greg	2.28	static const char RCSid[] = "$Id: image.c,v 2.27 2004/02/12 18:55:50 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	schorsch	2.22	#include "rtio.h"
13	greg	2.28	#include "rtmath.h"
14	greg	2.27	#include "paths.h"
15	greg	1.1	#include "view.h"
16
17	greg	2.4
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	schorsch	2.26	static gethfunc gethview;
25
26	greg	1.1
27			char *
28	greg	1.5	setview(v) /* set hvec and vvec, return message on error */
29			register VIEW *v;
30	greg	1.3	{
31	greg	1.12	static char ill_horiz[] = "illegal horizontal view size";
32			static char ill_vert[] = "illegal vertical view size";
33
34	gwlarson	2.15	if (v->vaft < -FTINY \|\| (v->vaft > FTINY && v->vaft <= v->vfore))
35	greg	2.7	return("illegal fore/aft clipping plane");
36
37	greg	1.1	if (normalize(v->vdir) == 0.0) /* normalize direction */
38			return("zero view direction");
39
40	greg	1.14	if (normalize(v->vup) == 0.0) /* normalize view up */
41			return("zero view up vector");
42
43	greg	1.5	fcross(v->hvec, v->vdir, v->vup); /* compute horiz dir */
44
45			if (normalize(v->hvec) == 0.0)
46	greg	1.14	return("view up parallel to view direction");
47	greg	1.1
48	greg	1.5	fcross(v->vvec, v->hvec, v->vdir); /* compute vert dir */
49
50	greg	1.12	if (v->horiz <= FTINY)
51			return(ill_horiz);
52			if (v->vert <= FTINY)
53			return(ill_vert);
54
55			switch (v->type) {
56			case VT_PAR: /* parallel view */
57	greg	1.5	v->hn2 = v->horiz;
58	greg	1.12	v->vn2 = v->vert;
59			break;
60			case VT_PER: /* perspective view */
61			if (v->horiz >= 180.0-FTINY)
62			return(ill_horiz);
63			if (v->vert >= 180.0-FTINY)
64			return(ill_vert);
65	greg	1.5	v->hn2 = 2.0 * tan(v->horiz*(PI/180.0/2.0));
66	greg	1.12	v->vn2 = 2.0 * tan(v->vert*(PI/180.0/2.0));
67			break;
68	greg	2.9	case VT_CYL: /* cylindrical panorama */
69			if (v->horiz > 360.0+FTINY)
70			return(ill_horiz);
71			if (v->vert >= 180.0-FTINY)
72			return(ill_vert);
73			v->hn2 = v->horiz * (PI/180.0);
74			v->vn2 = 2.0 * tan(v->vert*(PI/180.0/2.0));
75			break;
76	greg	1.12	case VT_ANG: /* angular fisheye */
77			if (v->horiz > 360.0+FTINY)
78			return(ill_horiz);
79			if (v->vert > 360.0+FTINY)
80			return(ill_vert);
81	greg	2.9	v->hn2 = v->horiz * (PI/180.0);
82			v->vn2 = v->vert * (PI/180.0);
83	greg	1.12	break;
84			case VT_HEM: /* hemispherical fisheye */
85			if (v->horiz > 180.0+FTINY)
86			return(ill_horiz);
87			if (v->vert > 180.0+FTINY)
88			return(ill_vert);
89			v->hn2 = 2.0 * sin(v->horiz*(PI/180.0/2.0));
90			v->vn2 = 2.0 * sin(v->vert*(PI/180.0/2.0));
91			break;
92			default:
93	greg	1.1	return("unknown view type");
94	greg	1.12	}
95	greg	1.13	if (v->type != VT_ANG) {
96	greg	2.9	if (v->type != VT_CYL) {
97			v->hvec[0] *= v->hn2;
98			v->hvec[1] *= v->hn2;
99			v->hvec[2] *= v->hn2;
100			}
101	greg	1.12	v->vvec[0] *= v->vn2;
102			v->vvec[1] *= v->vn2;
103			v->vvec[2] *= v->vn2;
104			}
105	greg	1.5	v->hn2 *= v->hn2;
106			v->vn2 *= v->vn2;
107	greg	1.1
108			return(NULL);
109			}
110
111
112	greg	2.16	void
113	greg	1.7	normaspect(va, ap, xp, yp) /* fix pixel aspect or resolution */
114			double va; /* view aspect ratio */
115			double ap; / pixel aspect in (or out if 0) */
116			int xp, yp; /* x and y resolution in (or out if ap!=0) /
117	greg	1.6	{
118			if (*ap <= FTINY)
119	greg	1.7	ap = va xp / yp; /* compute pixel aspect */
120	greg	1.6	else if (va * xp > ap * *yp)
121	greg	1.10	xp = yp / va * ap + .5; / reduce x resolution */
122	greg	1.6	else
123	greg	1.10	yp = xp * va / ap + .5; / reduce y resolution */
124	greg	1.6	}
125
126
127	greg	2.7	double
128	greg	1.5	viewray(orig, direc, v, x, y) /* compute ray origin and direction */
129	greg	1.1	FVECT orig, direc;
130			register VIEW *v;
131			double x, y;
132			{
133	greg	1.12	double d, z;
134
135	greg	1.5	x += v->hoff - 0.5;
136			y += v->voff - 0.5;
137	greg	1.1
138	greg	1.12	switch(v->type) {
139			case VT_PAR: /* parallel view */
140	greg	2.7	orig[0] = v->vp[0] + v->vfore*v->vdir[0]
141			+ xv->hvec[0] + yv->vvec[0];
142			orig[1] = v->vp[1] + v->vfore*v->vdir[1]
143			+ xv->hvec[1] + yv->vvec[1];
144			orig[2] = v->vp[2] + v->vfore*v->vdir[2]
145			+ xv->hvec[2] + yv->vvec[2];
146	greg	1.1	VCOPY(direc, v->vdir);
147	greg	2.8	return(v->vaft > FTINY ? v->vaft - v->vfore : 0.0);
148	greg	1.12	case VT_PER: /* perspective view */
149	greg	1.5	direc[0] = v->vdir[0] + xv->hvec[0] + yv->vvec[0];
150			direc[1] = v->vdir[1] + xv->hvec[1] + yv->vvec[1];
151			direc[2] = v->vdir[2] + xv->hvec[2] + yv->vvec[2];
152	greg	2.7	orig[0] = v->vp[0] + v->vfore*direc[0];
153			orig[1] = v->vp[1] + v->vfore*direc[1];
154			orig[2] = v->vp[2] + v->vfore*direc[2];
155			d = normalize(direc);
156	greg	2.8	return(v->vaft > FTINY ? (v->vaft - v->vfore)*d : 0.0);
157	greg	1.12	case VT_HEM: /* hemispherical fisheye */
158	greg	1.13	z = 1.0 - xxv->hn2 - yyv->vn2;
159	greg	1.12	if (z < 0.0)
160	greg	2.7	return(-1.0);
161	greg	1.12	z = sqrt(z);
162			direc[0] = zv->vdir[0] + xv->hvec[0] + y*v->vvec[0];
163			direc[1] = zv->vdir[1] + xv->hvec[1] + y*v->vvec[1];
164			direc[2] = zv->vdir[2] + xv->hvec[2] + y*v->vvec[2];
165	greg	2.7	orig[0] = v->vp[0] + v->vfore*direc[0];
166			orig[1] = v->vp[1] + v->vfore*direc[1];
167			orig[2] = v->vp[2] + v->vfore*direc[2];
168	greg	2.8	return(v->vaft > FTINY ? v->vaft - v->vfore : 0.0);
169	greg	2.9	case VT_CYL: /* cylindrical panorama */
170			d = x * v->horiz * (PI/180.0);
171			z = cos(d);
172			x = sin(d);
173			direc[0] = zv->vdir[0] + xv->hvec[0] + y*v->vvec[0];
174			direc[1] = zv->vdir[1] + xv->hvec[1] + y*v->vvec[1];
175			direc[2] = zv->vdir[2] + xv->hvec[2] + y*v->vvec[2];
176			orig[0] = v->vp[0] + v->vfore*direc[0];
177			orig[1] = v->vp[1] + v->vfore*direc[1];
178			orig[2] = v->vp[2] + v->vfore*direc[2];
179			d = normalize(direc);
180			return(v->vaft > FTINY ? (v->vaft - v->vfore)*d : 0.0);
181	greg	1.12	case VT_ANG: /* angular fisheye */
182			x *= v->horiz/180.0;
183			y *= v->vert/180.0;
184			d = xx + yy;
185			if (d > 1.0)
186	greg	2.7	return(-1.0);
187	greg	1.12	d = sqrt(d);
188			z = cos(PI*d);
189	greg	2.6	d = d <= FTINY ? PI : sqrt(1 - z*z)/d;
190	greg	1.12	x *= d;
191			y *= d;
192			direc[0] = zv->vdir[0] + xv->hvec[0] + y*v->vvec[0];
193			direc[1] = zv->vdir[1] + xv->hvec[1] + y*v->vvec[1];
194			direc[2] = zv->vdir[2] + xv->hvec[2] + y*v->vvec[2];
195	greg	2.7	orig[0] = v->vp[0] + v->vfore*direc[0];
196			orig[1] = v->vp[1] + v->vfore*direc[1];
197			orig[2] = v->vp[2] + v->vfore*direc[2];
198	greg	2.8	return(v->vaft > FTINY ? v->vaft - v->vfore : 0.0);
199	greg	1.1	}
200	greg	2.7	return(-1.0);
201	greg	1.1	}
202
203
204	greg	2.16	void
205	greg	1.17	viewloc(ip, v, p) /* find image location for point */
206			FVECT ip;
207	greg	1.3	register VIEW *v;
208			FVECT p;
209			{
210	gregl	2.13	double d, d2;
211	greg	1.3	FVECT disp;
212	greg	1.5
213	greg	1.3	disp[0] = p[0] - v->vp[0];
214			disp[1] = p[1] - v->vp[1];
215			disp[2] = p[2] - v->vp[2];
216
217	greg	1.12	switch (v->type) {
218			case VT_PAR: /* parallel view */
219	greg	2.7	ip[2] = DOT(disp,v->vdir) - v->vfore;
220	greg	1.13	break;
221	greg	1.12	case VT_PER: /* perspective view */
222	greg	1.11	d = DOT(disp,v->vdir);
223	gregl	2.13	ip[2] = VLEN(disp);
224	greg	1.17	if (d < 0.0) { /* fold pyramid */
225			ip[2] = -ip[2];
226	greg	1.11	d = -d;
227	greg	2.7	}
228			if (d > FTINY) {
229	greg	1.11	d = 1.0/d;
230			disp[0] *= d;
231			disp[1] *= d;
232			disp[2] *= d;
233			}
234	greg	2.7	ip[2] = (1.0 - v->vfored);
235	greg	1.13	break;
236	greg	1.12	case VT_HEM: /* hemispherical fisheye */
237			d = normalize(disp);
238	greg	1.17	if (DOT(disp,v->vdir) < 0.0)
239			ip[2] = -d;
240			else
241			ip[2] = d;
242	greg	2.7	ip[2] -= v->vfore;
243	greg	1.13	break;
244	greg	2.9	case VT_CYL: /* cylindrical panorama */
245			d = DOT(disp,v->hvec);
246	gregl	2.13	d2 = DOT(disp,v->vdir);
247			ip[0] = 180.0/PI * atan2(d,d2) / v->horiz + 0.5 - v->hoff;
248			d = 1.0/sqrt(dd + d2d2);
249			ip[1] = DOT(disp,v->vvec)*d/v->vn2 + 0.5 - v->voff;
250			ip[2] = VLEN(disp);
251	gwlarson	2.15	ip[2] = (1.0 - v->vfored);
252	greg	2.9	return;
253	greg	1.12	case VT_ANG: /* angular fisheye */
254	greg	1.17	ip[0] = 0.5 - v->hoff;
255			ip[1] = 0.5 - v->voff;
256	greg	2.7	ip[2] = normalize(disp) - v->vfore;
257	greg	1.12	d = DOT(disp,v->vdir);
258			if (d >= 1.0-FTINY)
259			return;
260			if (d <= -(1.0-FTINY)) {
261	greg	2.7	ip[0] += 180.0/v->horiz;
262	greg	1.12	return;
263			}
264			d = acos(d)/PI / sqrt(1.0 - d*d);
265	greg	1.17	ip[0] += DOT(disp,v->hvec)d180.0/v->horiz;
266			ip[1] += DOT(disp,v->vvec)d180.0/v->vert;
267	greg	1.12	return;
268	greg	1.3	}
269	greg	1.17	ip[0] = DOT(disp,v->hvec)/v->hn2 + 0.5 - v->hoff;
270			ip[1] = DOT(disp,v->vvec)/v->vn2 + 0.5 - v->voff;
271	greg	1.3	}
272
273
274	greg	2.16	void
275	greg	1.17	pix2loc(loc, rp, px, py) /* compute image location from pixel pos. */
276	schorsch	2.18	RREAL loc[2];
277	greg	1.17	register RESOLU *rp;
278			int px, py;
279			{
280			register int x, y;
281
282	greg	2.16	if (rp->rt & YMAJOR) {
283	greg	1.17	x = px;
284			y = py;
285			} else {
286			x = py;
287			y = px;
288			}
289	greg	2.16	if (rp->rt & XDECR)
290	greg	1.17	x = rp->xr-1 - x;
291	greg	2.16	if (rp->rt & YDECR)
292	greg	1.17	y = rp->yr-1 - y;
293			loc[0] = (x+.5)/rp->xr;
294			loc[1] = (y+.5)/rp->yr;
295			}
296
297
298	greg	2.16	void
299	greg	1.17	loc2pix(pp, rp, lx, ly) /* compute pixel pos. from image location */
300			int pp[2];
301			register RESOLU *rp;
302			double lx, ly;
303			{
304			register int x, y;
305
306			x = lx * rp->xr;
307			y = ly * rp->yr;
308	greg	2.16	if (rp->rt & XDECR)
309	greg	1.17	x = rp->xr-1 - x;
310	greg	2.16	if (rp->rt & YDECR)
311	greg	1.17	y = rp->yr-1 - y;
312	greg	2.16	if (rp->rt & YMAJOR) {
313	greg	1.17	pp[0] = x;
314			pp[1] = y;
315			} else {
316			pp[0] = y;
317			pp[1] = x;
318			}
319			}
320
321
322	greg	1.5	int
323			getviewopt(v, ac, av) /* process view argument */
324			register VIEW *v;
325			int ac;
326			register char *av[];
327			{
328	greg	1.16	#define check(c,l) if ((av[0][c]&&av[0][c]!=' ') \|\| \
329			badarg(ac-1,av+1,l)) return(-1)
330	greg	1.5
331	greg	1.9	if (ac <= 0 \|\| av[0][0] != '-' \|\| av[0][1] != 'v')
332	greg	1.5	return(-1);
333			switch (av[0][2]) {
334			case 't': /* type */
335			if (!av[0][3] \|\| av[0][3]==' ')
336			return(-1);
337	greg	1.16	check(4,"");
338	greg	1.5	v->type = av[0][3];
339			return(0);
340			case 'p': /* point */
341	greg	1.16	check(3,"fff");
342	greg	1.5	v->vp[0] = atof(av[1]);
343			v->vp[1] = atof(av[2]);
344			v->vp[2] = atof(av[3]);
345			return(3);
346			case 'd': /* direction */
347	greg	1.16	check(3,"fff");
348	greg	1.5	v->vdir[0] = atof(av[1]);
349			v->vdir[1] = atof(av[2]);
350			v->vdir[2] = atof(av[3]);
351			return(3);
352			case 'u': /* up */
353	greg	1.16	check(3,"fff");
354	greg	1.5	v->vup[0] = atof(av[1]);
355			v->vup[1] = atof(av[2]);
356			v->vup[2] = atof(av[3]);
357			return(3);
358			case 'h': /* horizontal size */
359	greg	1.16	check(3,"f");
360	greg	1.5	v->horiz = atof(av[1]);
361			return(1);
362			case 'v': /* vertical size */
363	greg	1.16	check(3,"f");
364	greg	1.5	v->vert = atof(av[1]);
365			return(1);
366	greg	2.7	case 'o': /* fore clipping plane */
367			check(3,"f");
368			v->vfore = atof(av[1]);
369			return(1);
370			case 'a': /* aft clipping plane */
371			check(3,"f");
372			v->vaft = atof(av[1]);
373			return(1);
374	greg	1.5	case 's': /* shift */
375	greg	1.16	check(3,"f");
376	greg	1.5	v->hoff = atof(av[1]);
377			return(1);
378			case 'l': /* lift */
379	greg	1.16	check(3,"f");
380	greg	1.5	v->voff = atof(av[1]);
381			return(1);
382			default:
383			return(-1);
384			}
385			#undef check
386			}
387
388
389			int
390			sscanview(vp, s) /* get view parameters from string */
391			VIEW *vp;
392	greg	1.1	register char *s;
393			{
394	greg	1.5	int ac;
395			char *av[4];
396			int na;
397			int nvopts = 0;
398
399	greg	2.20	while (*s == ' ')
400	greg	2.19	s++;
401	greg	2.20	if (*s != '-')
402			s = sskip2(s,1);
403	greg	1.9	while (*s) {
404	greg	1.5	ac = 0;
405			do {
406	greg	2.21	if (ac \|\| *s == '-')
407			av[ac++] = s;
408	greg	1.5	while (s && s != ' ')
409			s++;
410			while (*s == ' ')
411			s++;
412			} while (*s && ac < 4);
413			if ((na = getviewopt(vp, ac, av)) >= 0) {
414			if (na+1 < ac)
415			s = av[na+1];
416			nvopts++;
417	greg	1.9	} else if (ac > 1)
418			s = av[1];
419			}
420	greg	1.5	return(nvopts);
421	greg	1.1	}
422
423
424	greg	2.16	void
425	greg	1.1	fprintview(vp, fp) /* write out view parameters */
426			register VIEW *vp;
427			FILE *fp;
428			{
429			fprintf(fp, " -vt%c", vp->type);
430			fprintf(fp, " -vp %.6g %.6g %.6g", vp->vp[0], vp->vp[1], vp->vp[2]);
431			fprintf(fp, " -vd %.6g %.6g %.6g", vp->vdir[0], vp->vdir[1], vp->vdir[2]);
432			fprintf(fp, " -vu %.6g %.6g %.6g", vp->vup[0], vp->vup[1], vp->vup[2]);
433			fprintf(fp, " -vh %.6g -vv %.6g", vp->horiz, vp->vert);
434	greg	2.7	fprintf(fp, " -vo %.6g -va %.6g", vp->vfore, vp->vaft);
435	greg	1.9	fprintf(fp, " -vs %.6g -vl %.6g", vp->hoff, vp->voff);
436	greg	2.11	}
437
438
439			char *
440			viewopt(vp) /* translate to minimal view string */
441			register VIEW *vp;
442			{
443			static char vwstr[128];
444			register char *cp = vwstr;
445
446			if (vp->type != stdview.type) {
447			sprintf(cp, " -vt%c", vp->type);
448			cp += strlen(cp);
449			}
450			if (!VEQ(vp->vp,stdview.vp)) {
451			sprintf(cp, " -vp %.6g %.6g %.6g",
452			vp->vp[0], vp->vp[1], vp->vp[2]);
453			cp += strlen(cp);
454			}
455			if (!VEQ(vp->vdir,stdview.vdir)) {
456			sprintf(cp, " -vd %.6g %.6g %.6g",
457			vp->vdir[0], vp->vdir[1], vp->vdir[2]);
458			cp += strlen(cp);
459			}
460			if (!VEQ(vp->vup,stdview.vup)) {
461			sprintf(cp, " -vu %.6g %.6g %.6g",
462			vp->vup[0], vp->vup[1], vp->vup[2]);
463			cp += strlen(cp);
464			}
465			if (!FEQ(vp->horiz,stdview.horiz)) {
466			sprintf(cp, " -vh %.6g", vp->horiz);
467			cp += strlen(cp);
468			}
469			if (!FEQ(vp->vert,stdview.vert)) {
470			sprintf(cp, " -vv %.6g", vp->vert);
471			cp += strlen(cp);
472			}
473			if (!FEQ(vp->vfore,stdview.vfore)) {
474			sprintf(cp, " -vo %.6g", vp->vfore);
475			cp += strlen(cp);
476			}
477			if (!FEQ(vp->vaft,stdview.vaft)) {
478			sprintf(cp, " -va %.6g", vp->vaft);
479			cp += strlen(cp);
480			}
481			if (!FEQ(vp->hoff,stdview.hoff)) {
482			sprintf(cp, " -vs %.6g", vp->hoff);
483			cp += strlen(cp);
484			}
485			if (!FEQ(vp->voff,stdview.voff)) {
486			sprintf(cp, " -vl %.6g", vp->voff);
487			cp += strlen(cp);
488			}
489			return(vwstr);
490	greg	1.1	}
491
492
493	greg	2.3	int
494			isview(s) /* is this a view string? */
495			char *s;
496			{
497	greg	2.25	static char *altname[]={NULL,VIEWSTR,"rpict","rview","rvu","rpiece","pinterp",NULL};
498	greg	2.5	extern char *progname;
499	greg	2.3	register char *cp;
500			register char **an;
501			/* add program name to list */
502	greg	2.5	if (altname[0] == NULL) {
503			for (cp = progname; *cp; cp++)
504			;
505			while (cp > progname && !ISDIRSEP(cp[-1]))
506			cp--;
507			altname[0] = cp;
508			}
509	greg	2.3	/* skip leading path */
510			cp = s;
511			while (cp && cp != ' ')
512			cp++;
513	greg	2.5	while (cp > s && !ISDIRSEP(cp[-1]))
514	greg	2.3	cp--;
515			for (an = altname; *an != NULL; an++)
516			if (!strncmp(an, cp, strlen(an)))
517			return(1);
518			return(0);
519			}
520	greg	1.1
521	greg	2.3
522	greg	1.15	struct myview {
523			VIEW *hv;
524			int ok;
525			};
526	greg	1.1
527	greg	1.15
528	gwlarson	2.14	static int
529	schorsch	2.26	gethview( /* get view from header */
530			char *s,
531			void *v
532			)
533	greg	1.1	{
534	schorsch	2.26	if (isview(s) && sscanview(((struct myview*)v)->hv, s) > 0)
535			((struct myview*)v)->ok++;
536	gwlarson	2.14	return(0);
537	greg	1.1	}
538
539
540			int
541	greg	1.17	viewfile(fname, vp, rp) /* get view from file */
542	greg	1.1	char *fname;
543			VIEW *vp;
544	greg	1.17	RESOLU *rp;
545	greg	1.1	{
546	greg	1.15	struct myview mvs;
547	greg	1.1	FILE *fp;
548
549	greg	2.16	if (fname == NULL \|\| !strcmp(fname, "-"))
550			fp = stdin;
551			else if ((fp = fopen(fname, "r")) == NULL)
552	greg	1.1	return(-1);
553
554	greg	1.15	mvs.hv = vp;
555			mvs.ok = 0;
556	greg	1.1
557	schorsch	2.26	getheader(fp, gethview, &mvs);
558	greg	1.8
559	greg	1.17	if (rp != NULL && !fgetsresolu(rp, fp))
560	greg	1.15	mvs.ok = 0;
561	greg	1.1
562			fclose(fp);
563
564	greg	1.15	return(mvs.ok);
565	greg	1.1	}