src/common/image.c

#ifndef lint
static const char       RCSid[] = "$Id: image.c,v 2.38 2012/11/16 00:14:19 greg Exp $";
#endif
/*
 *  image.c - routines for image generation.
 *
 *  External symbols declared in view.h
 */

#include "copyright.h"

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

        if (v->vdist <= FTINY)
                return("illegal view distance");
        v->vdist *= normalize(v->vdir);         /* normalize direction */
        if (v->vdist == 0.0)
                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;
        case VT_PLS:                            /* planispheric fisheye */
                if (v->horiz >= 360.0-FTINY)
                        return(ill_horiz);
                if (v->vert >= 360.0-FTINY)
                        return(ill_vert);
                v->hn2 = 2.*sin(v->horiz*(PI/180.0/2.0)) /
                                (1.0 + cos(v->horiz*(PI/180.0/2.0)));
                v->vn2 = 2.*sin(v->vert*(PI/180.0/2.0)) /
                                (1.0 + cos(v->vert*(PI/180.0/2.0)));
                break;
        default:
                return("unknown view type");
        }
        if (v->type != VT_ANG && v->type != VT_PLS) {
                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(                             /* fix pixel aspect or resolution */
double  va,                     /* view aspect ratio */
double  *ap,                    /* pixel aspect in (or out if 0) */
int  *xp,
int  *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(                                /* compute ray origin and direction */
FVECT  orig,
FVECT  direc,
VIEW  *v,
double  x,
double  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 *= (1.0/180.0)*v->horiz;
                y *= (1.0/180.0)*v->vert;
                d = x*x + y*y;
                if (d > 1.0)
                        return(-1.0);
                d = sqrt(d);
                z = cos(PI*d);
                d = d <= FTINY ? PI : sqrt(1.0 - 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);
        case VT_PLS:                    /* planispheric fisheye */
                x *= sqrt(v->hn2);
                y *= sqrt(v->vn2);
                d = x*x + y*y;
                z = (1. - d)/(1. + d);
                x *= (1. + z);
                y *= (1. + 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);
        }
        return(-1.0);
}


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

        VSUB(disp, p, v->vp);

        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 = (180.0/PI)*acos(d) / sqrt(1.0 - d*d);
                ip[0] += DOT(disp,v->hvec)*d/v->horiz;
                ip[1] += DOT(disp,v->vvec)*d/v->vert;
                return;
        case VT_PLS:                    /* planispheric 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))
                        return;         /* really an error */
                ip[0] += DOT(disp,v->hvec)/((1. + d)*sqrt(v->hn2));
                ip[1] += DOT(disp,v->vvec)/((1. + d)*sqrt(v->vn2));
                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(                /* compute image location from pixel pos. */
RREAL  loc[2],
RESOLU  *rp,
int  px,
int  py
)
{
        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(                        /* compute pixel pos. from image location */
int  pp[2],
RESOLU  *rp,
double  lx,
double  ly
)
{
        int  x, y;

        x = (int)(lx*rp->xr + .5 - (lx < 0.0));
        y = (int)(ly*rp->yr + .5 - (ly < 0.0));

        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(                             /* process view argument */
VIEW  *v,
int  ac,
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]);
                v->vdist = 1.;
                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(                              /* get view parameters from string */
VIEW  *vp,
char  *s
)
{
        int  ac;
        char  *av[4];
        int  na;
        int  nvopts = 0;

        while (isspace(*s))
                if (!*s++)
                        return(0);
        while (*s) {
                ac = 0;
                do {
                        if (ac || *s == '-')
                                av[ac++] = s;
                        while (*s && !isspace(*s))
                                s++;
                        while (isspace(*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(                             /* write out view parameters */
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->vdist,
                                                vp->vdir[1]*vp->vdist,
                                                vp->vdir[2]*vp->vdist);
        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(                                /* translate to minimal view string */
VIEW  *vp
)
{
        static char  vwstr[128];
        char  *cp = vwstr;

        *cp = '\0';
        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 (!FEQ(vp->vdist,stdview.vdist) || !VEQ(vp->vdir,stdview.vdir)) {
                sprintf(cp, " -vd %.6g %.6g %.6g",
                                vp->vdir[0]*vp->vdist,
                                vp->vdir[1]*vp->vdist,
                                vp->vdir[2]*vp->vdist);
                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(                                 /* is this a view string? */
char  *s
)
{
        static char  *altname[]={NULL,VIEWSTR,"rpict","rview","rvu","rpiece","pinterp",NULL};
        extern char  *progname;
        char  *cp;
        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(                               /* 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:	2.39
Committed:	Sun Mar 24 19:40:26 2013 UTC (11 years, 1 month ago) by greg
Content type:	text/plain
Branch:	MAIN
Changes since 2.38:	+3 -2 lines
Log Message:	Added check for negative fore clipping plane
#	User	Rev	Content
1	greg	1.1	#ifndef lint
2	greg	2.39	static const char RCSid[] = "$Id: image.c,v 2.38 2012/11/16 00:14:19 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	greg	2.32	#include <ctype.h>
13	schorsch	2.22	#include "rtio.h"
14	greg	2.28	#include "rtmath.h"
15	greg	2.27	#include "paths.h"
16	greg	1.1	#include "view.h"
17
18	greg	2.4
19	greg	2.11	#define FEQ(x,y) (fabs((x)-(y)) <= FTINY)
20			#define VEQ(v,w) (FEQ((v)[0],(w)[0]) && FEQ((v)[1],(w)[1]) \
21			&& FEQ((v)[2],(w)[2]))
22
23	greg	1.5	VIEW stdview = STDVIEW; /* default view parameters */
24	greg	1.1
25	schorsch	2.26	static gethfunc gethview;
26
27	greg	1.1
28			char *
29	greg	2.35	setview( /* set hvec and vvec, return message on error */
30			VIEW *v
31			)
32	greg	1.3	{
33	greg	1.12	static char ill_horiz[] = "illegal horizontal view size";
34			static char ill_vert[] = "illegal vertical view size";
35
36	greg	2.39	if ((v->vfore < -FTINY) \| (v->vaft < -FTINY) \|\|
37			(v->vaft > FTINY) & (v->vaft <= v->vfore))
38	greg	2.7	return("illegal fore/aft clipping plane");
39
40	greg	2.31	if (v->vdist <= FTINY)
41			return("illegal view distance");
42	greg	2.29	v->vdist = normalize(v->vdir); / normalize direction */
43			if (v->vdist == 0.0)
44	greg	1.1	return("zero view direction");
45
46	greg	1.14	if (normalize(v->vup) == 0.0) /* normalize view up */
47			return("zero view up vector");
48
49	greg	1.5	fcross(v->hvec, v->vdir, v->vup); /* compute horiz dir */
50
51			if (normalize(v->hvec) == 0.0)
52	greg	1.14	return("view up parallel to view direction");
53	greg	1.1
54	greg	1.5	fcross(v->vvec, v->hvec, v->vdir); /* compute vert dir */
55
56	greg	1.12	if (v->horiz <= FTINY)
57			return(ill_horiz);
58			if (v->vert <= FTINY)
59			return(ill_vert);
60
61			switch (v->type) {
62			case VT_PAR: /* parallel view */
63	greg	1.5	v->hn2 = v->horiz;
64	greg	1.12	v->vn2 = v->vert;
65			break;
66			case VT_PER: /* perspective view */
67			if (v->horiz >= 180.0-FTINY)
68			return(ill_horiz);
69			if (v->vert >= 180.0-FTINY)
70			return(ill_vert);
71	greg	1.5	v->hn2 = 2.0 * tan(v->horiz*(PI/180.0/2.0));
72	greg	1.12	v->vn2 = 2.0 * tan(v->vert*(PI/180.0/2.0));
73			break;
74	greg	2.9	case VT_CYL: /* cylindrical panorama */
75			if (v->horiz > 360.0+FTINY)
76			return(ill_horiz);
77			if (v->vert >= 180.0-FTINY)
78			return(ill_vert);
79			v->hn2 = v->horiz * (PI/180.0);
80			v->vn2 = 2.0 * tan(v->vert*(PI/180.0/2.0));
81			break;
82	greg	1.12	case VT_ANG: /* angular fisheye */
83			if (v->horiz > 360.0+FTINY)
84			return(ill_horiz);
85			if (v->vert > 360.0+FTINY)
86			return(ill_vert);
87	greg	2.9	v->hn2 = v->horiz * (PI/180.0);
88			v->vn2 = v->vert * (PI/180.0);
89	greg	1.12	break;
90			case VT_HEM: /* hemispherical fisheye */
91			if (v->horiz > 180.0+FTINY)
92			return(ill_horiz);
93			if (v->vert > 180.0+FTINY)
94			return(ill_vert);
95			v->hn2 = 2.0 * sin(v->horiz*(PI/180.0/2.0));
96			v->vn2 = 2.0 * sin(v->vert*(PI/180.0/2.0));
97			break;
98	greg	2.34	case VT_PLS: /* planispheric fisheye */
99			if (v->horiz >= 360.0-FTINY)
100			return(ill_horiz);
101			if (v->vert >= 360.0-FTINY)
102			return(ill_vert);
103			v->hn2 = 2.sin(v->horiz(PI/180.0/2.0)) /
104			(1.0 + cos(v->horiz*(PI/180.0/2.0)));
105			v->vn2 = 2.sin(v->vert(PI/180.0/2.0)) /
106			(1.0 + cos(v->vert*(PI/180.0/2.0)));
107			break;
108	greg	1.12	default:
109	greg	1.1	return("unknown view type");
110	greg	1.12	}
111	greg	2.34	if (v->type != VT_ANG && v->type != VT_PLS) {
112	greg	2.9	if (v->type != VT_CYL) {
113			v->hvec[0] *= v->hn2;
114			v->hvec[1] *= v->hn2;
115			v->hvec[2] *= v->hn2;
116			}
117	greg	1.12	v->vvec[0] *= v->vn2;
118			v->vvec[1] *= v->vn2;
119			v->vvec[2] *= v->vn2;
120			}
121	greg	1.5	v->hn2 *= v->hn2;
122			v->vn2 *= v->vn2;
123	greg	1.1
124			return(NULL);
125			}
126
127
128	greg	2.16	void
129	greg	2.35	normaspect( /* fix pixel aspect or resolution */
130			double va, /* view aspect ratio */
131			double ap, / pixel aspect in (or out if 0) */
132			int *xp,
133			int yp / x and y resolution in (or out if ap!=0) /
134			)
135	greg	1.6	{
136			if (*ap <= FTINY)
137	greg	1.7	ap = va xp / yp; /* compute pixel aspect */
138	greg	1.6	else if (va * xp > ap * *yp)
139	greg	1.10	xp = yp / va * ap + .5; / reduce x resolution */
140	greg	1.6	else
141	greg	1.10	yp = xp * va / ap + .5; / reduce y resolution */
142	greg	1.6	}
143
144
145	greg	2.7	double
146	greg	2.35	viewray( /* compute ray origin and direction */
147			FVECT orig,
148			FVECT direc,
149			VIEW *v,
150			double x,
151			double y
152			)
153	greg	1.1	{
154	greg	1.12	double d, z;
155
156	greg	1.5	x += v->hoff - 0.5;
157			y += v->voff - 0.5;
158	greg	1.1
159	greg	1.12	switch(v->type) {
160			case VT_PAR: /* parallel view */
161	greg	2.7	orig[0] = v->vp[0] + v->vfore*v->vdir[0]
162			+ xv->hvec[0] + yv->vvec[0];
163			orig[1] = v->vp[1] + v->vfore*v->vdir[1]
164			+ xv->hvec[1] + yv->vvec[1];
165			orig[2] = v->vp[2] + v->vfore*v->vdir[2]
166			+ xv->hvec[2] + yv->vvec[2];
167	greg	1.1	VCOPY(direc, v->vdir);
168	greg	2.8	return(v->vaft > FTINY ? v->vaft - v->vfore : 0.0);
169	greg	1.12	case VT_PER: /* perspective view */
170	greg	1.5	direc[0] = v->vdir[0] + xv->hvec[0] + yv->vvec[0];
171			direc[1] = v->vdir[1] + xv->hvec[1] + yv->vvec[1];
172			direc[2] = v->vdir[2] + xv->hvec[2] + yv->vvec[2];
173	greg	2.7	orig[0] = v->vp[0] + v->vfore*direc[0];
174			orig[1] = v->vp[1] + v->vfore*direc[1];
175			orig[2] = v->vp[2] + v->vfore*direc[2];
176			d = normalize(direc);
177	greg	2.8	return(v->vaft > FTINY ? (v->vaft - v->vfore)*d : 0.0);
178	greg	1.12	case VT_HEM: /* hemispherical fisheye */
179	greg	1.13	z = 1.0 - xxv->hn2 - yyv->vn2;
180	greg	1.12	if (z < 0.0)
181	greg	2.7	return(-1.0);
182	greg	1.12	z = sqrt(z);
183			direc[0] = zv->vdir[0] + xv->hvec[0] + y*v->vvec[0];
184			direc[1] = zv->vdir[1] + xv->hvec[1] + y*v->vvec[1];
185			direc[2] = zv->vdir[2] + xv->hvec[2] + y*v->vvec[2];
186	greg	2.7	orig[0] = v->vp[0] + v->vfore*direc[0];
187			orig[1] = v->vp[1] + v->vfore*direc[1];
188			orig[2] = v->vp[2] + v->vfore*direc[2];
189	greg	2.8	return(v->vaft > FTINY ? v->vaft - v->vfore : 0.0);
190	greg	2.9	case VT_CYL: /* cylindrical panorama */
191			d = x * v->horiz * (PI/180.0);
192			z = cos(d);
193			x = sin(d);
194			direc[0] = zv->vdir[0] + xv->hvec[0] + y*v->vvec[0];
195			direc[1] = zv->vdir[1] + xv->hvec[1] + y*v->vvec[1];
196			direc[2] = zv->vdir[2] + xv->hvec[2] + y*v->vvec[2];
197			orig[0] = v->vp[0] + v->vfore*direc[0];
198			orig[1] = v->vp[1] + v->vfore*direc[1];
199			orig[2] = v->vp[2] + v->vfore*direc[2];
200			d = normalize(direc);
201			return(v->vaft > FTINY ? (v->vaft - v->vfore)*d : 0.0);
202	greg	1.12	case VT_ANG: /* angular fisheye */
203	greg	2.34	x = (1.0/180.0)v->horiz;
204			y = (1.0/180.0)v->vert;
205	greg	1.12	d = xx + yy;
206			if (d > 1.0)
207	greg	2.7	return(-1.0);
208	greg	1.12	d = sqrt(d);
209			z = cos(PI*d);
210	greg	2.34	d = d <= FTINY ? PI : sqrt(1.0 - z*z)/d;
211			x *= d;
212			y *= d;
213			direc[0] = zv->vdir[0] + xv->hvec[0] + y*v->vvec[0];
214			direc[1] = zv->vdir[1] + xv->hvec[1] + y*v->vvec[1];
215			direc[2] = zv->vdir[2] + xv->hvec[2] + y*v->vvec[2];
216			orig[0] = v->vp[0] + v->vfore*direc[0];
217			orig[1] = v->vp[1] + v->vfore*direc[1];
218			orig[2] = v->vp[2] + v->vfore*direc[2];
219			return(v->vaft > FTINY ? v->vaft - v->vfore : 0.0);
220			case VT_PLS: /* planispheric fisheye */
221			x *= sqrt(v->hn2);
222			y *= sqrt(v->vn2);
223			d = xx + yy;
224			z = (1. - d)/(1. + d);
225	greg	2.38	x *= (1. + z);
226			y *= (1. + z);
227	greg	1.12	direc[0] = zv->vdir[0] + xv->hvec[0] + y*v->vvec[0];
228			direc[1] = zv->vdir[1] + xv->hvec[1] + y*v->vvec[1];
229			direc[2] = zv->vdir[2] + xv->hvec[2] + y*v->vvec[2];
230	greg	2.7	orig[0] = v->vp[0] + v->vfore*direc[0];
231			orig[1] = v->vp[1] + v->vfore*direc[1];
232			orig[2] = v->vp[2] + v->vfore*direc[2];
233	greg	2.8	return(v->vaft > FTINY ? v->vaft - v->vfore : 0.0);
234	greg	1.1	}
235	greg	2.7	return(-1.0);
236	greg	1.1	}
237
238
239	greg	2.16	void
240	greg	2.35	viewloc( /* find image location for point */
241			FVECT ip,
242			VIEW *v,
243			FVECT p
244			)
245	greg	1.3	{
246	gregl	2.13	double d, d2;
247	greg	1.3	FVECT disp;
248	greg	1.5
249	greg	2.34	VSUB(disp, p, v->vp);
250	greg	1.3
251	greg	1.12	switch (v->type) {
252			case VT_PAR: /* parallel view */
253	greg	2.7	ip[2] = DOT(disp,v->vdir) - v->vfore;
254	greg	1.13	break;
255	greg	1.12	case VT_PER: /* perspective view */
256	greg	1.11	d = DOT(disp,v->vdir);
257	gregl	2.13	ip[2] = VLEN(disp);
258	greg	1.17	if (d < 0.0) { /* fold pyramid */
259			ip[2] = -ip[2];
260	greg	1.11	d = -d;
261	greg	2.7	}
262			if (d > FTINY) {
263	greg	1.11	d = 1.0/d;
264			disp[0] *= d;
265			disp[1] *= d;
266			disp[2] *= d;
267			}
268	greg	2.7	ip[2] = (1.0 - v->vfored);
269	greg	1.13	break;
270	greg	1.12	case VT_HEM: /* hemispherical fisheye */
271			d = normalize(disp);
272	greg	1.17	if (DOT(disp,v->vdir) < 0.0)
273			ip[2] = -d;
274			else
275			ip[2] = d;
276	greg	2.7	ip[2] -= v->vfore;
277	greg	1.13	break;
278	greg	2.9	case VT_CYL: /* cylindrical panorama */
279			d = DOT(disp,v->hvec);
280	gregl	2.13	d2 = DOT(disp,v->vdir);
281			ip[0] = 180.0/PI * atan2(d,d2) / v->horiz + 0.5 - v->hoff;
282			d = 1.0/sqrt(dd + d2d2);
283			ip[1] = DOT(disp,v->vvec)*d/v->vn2 + 0.5 - v->voff;
284			ip[2] = VLEN(disp);
285	gwlarson	2.15	ip[2] = (1.0 - v->vfored);
286	greg	2.9	return;
287	greg	1.12	case VT_ANG: /* angular fisheye */
288	greg	1.17	ip[0] = 0.5 - v->hoff;
289			ip[1] = 0.5 - v->voff;
290	greg	2.7	ip[2] = normalize(disp) - v->vfore;
291	greg	1.12	d = DOT(disp,v->vdir);
292			if (d >= 1.0-FTINY)
293			return;
294			if (d <= -(1.0-FTINY)) {
295	greg	2.7	ip[0] += 180.0/v->horiz;
296	greg	1.12	return;
297			}
298	greg	2.34	d = (180.0/PI)acos(d) / sqrt(1.0 - dd);
299			ip[0] += DOT(disp,v->hvec)*d/v->horiz;
300			ip[1] += DOT(disp,v->vvec)*d/v->vert;
301			return;
302			case VT_PLS: /* planispheric fisheye */
303			ip[0] = 0.5 - v->hoff;
304			ip[1] = 0.5 - v->voff;
305			ip[2] = normalize(disp) - v->vfore;
306			d = DOT(disp,v->vdir);
307			if (d >= 1.0-FTINY)
308			return;
309			if (d <= -(1.0-FTINY))
310			return; /* really an error */
311	greg	2.38	ip[0] += DOT(disp,v->hvec)/((1. + d)*sqrt(v->hn2));
312			ip[1] += DOT(disp,v->vvec)/((1. + d)*sqrt(v->vn2));
313	greg	1.12	return;
314	greg	1.3	}
315	greg	1.17	ip[0] = DOT(disp,v->hvec)/v->hn2 + 0.5 - v->hoff;
316			ip[1] = DOT(disp,v->vvec)/v->vn2 + 0.5 - v->voff;
317	greg	1.3	}
318
319
320	greg	2.16	void
321	greg	2.35	pix2loc( /* compute image location from pixel pos. */
322			RREAL loc[2],
323			RESOLU *rp,
324			int px,
325			int py
326			)
327	greg	1.17	{
328	greg	2.36	int x, y;
329	greg	1.17
330	greg	2.16	if (rp->rt & YMAJOR) {
331	greg	1.17	x = px;
332			y = py;
333			} else {
334			x = py;
335			y = px;
336			}
337	greg	2.16	if (rp->rt & XDECR)
338	greg	1.17	x = rp->xr-1 - x;
339	greg	2.16	if (rp->rt & YDECR)
340	greg	1.17	y = rp->yr-1 - y;
341			loc[0] = (x+.5)/rp->xr;
342			loc[1] = (y+.5)/rp->yr;
343			}
344
345
346	greg	2.16	void
347	greg	2.35	loc2pix( /* compute pixel pos. from image location */
348			int pp[2],
349			RESOLU *rp,
350			double lx,
351			double ly
352			)
353	greg	1.17	{
354	greg	2.36	int x, y;
355	greg	1.17
356	greg	2.37	x = (int)(lx*rp->xr + .5 - (lx < 0.0));
357			y = (int)(ly*rp->yr + .5 - (ly < 0.0));
358
359	greg	2.16	if (rp->rt & XDECR)
360	greg	1.17	x = rp->xr-1 - x;
361	greg	2.16	if (rp->rt & YDECR)
362	greg	1.17	y = rp->yr-1 - y;
363	greg	2.16	if (rp->rt & YMAJOR) {
364	greg	1.17	pp[0] = x;
365			pp[1] = y;
366			} else {
367			pp[0] = y;
368			pp[1] = x;
369			}
370			}
371
372
373	greg	1.5	int
374	greg	2.35	getviewopt( /* process view argument */
375			VIEW *v,
376			int ac,
377			char *av[]
378			)
379	greg	1.5	{
380	greg	1.16	#define check(c,l) if ((av[0][c]&&av[0][c]!=' ') \|\| \
381			badarg(ac-1,av+1,l)) return(-1)
382	greg	1.5
383	greg	1.9	if (ac <= 0 \|\| av[0][0] != '-' \|\| av[0][1] != 'v')
384	greg	1.5	return(-1);
385			switch (av[0][2]) {
386			case 't': /* type */
387			if (!av[0][3] \|\| av[0][3]==' ')
388			return(-1);
389	greg	1.16	check(4,"");
390	greg	1.5	v->type = av[0][3];
391			return(0);
392			case 'p': /* point */
393	greg	1.16	check(3,"fff");
394	greg	1.5	v->vp[0] = atof(av[1]);
395			v->vp[1] = atof(av[2]);
396			v->vp[2] = atof(av[3]);
397			return(3);
398			case 'd': /* direction */
399	greg	1.16	check(3,"fff");
400	greg	1.5	v->vdir[0] = atof(av[1]);
401			v->vdir[1] = atof(av[2]);
402			v->vdir[2] = atof(av[3]);
403	greg	2.30	v->vdist = 1.;
404	greg	1.5	return(3);
405			case 'u': /* up */
406	greg	1.16	check(3,"fff");
407	greg	1.5	v->vup[0] = atof(av[1]);
408			v->vup[1] = atof(av[2]);
409			v->vup[2] = atof(av[3]);
410			return(3);
411			case 'h': /* horizontal size */
412	greg	1.16	check(3,"f");
413	greg	1.5	v->horiz = atof(av[1]);
414			return(1);
415			case 'v': /* vertical size */
416	greg	1.16	check(3,"f");
417	greg	1.5	v->vert = atof(av[1]);
418			return(1);
419	greg	2.7	case 'o': /* fore clipping plane */
420			check(3,"f");
421			v->vfore = atof(av[1]);
422			return(1);
423			case 'a': /* aft clipping plane */
424			check(3,"f");
425			v->vaft = atof(av[1]);
426			return(1);
427	greg	1.5	case 's': /* shift */
428	greg	1.16	check(3,"f");
429	greg	1.5	v->hoff = atof(av[1]);
430			return(1);
431			case 'l': /* lift */
432	greg	1.16	check(3,"f");
433	greg	1.5	v->voff = atof(av[1]);
434			return(1);
435			default:
436			return(-1);
437			}
438			#undef check
439			}
440
441
442			int
443	greg	2.35	sscanview( /* get view parameters from string */
444			VIEW *vp,
445			char *s
446			)
447	greg	1.1	{
448	greg	1.5	int ac;
449			char *av[4];
450			int na;
451			int nvopts = 0;
452
453	greg	2.32	while (isspace(*s))
454			if (!*s++)
455			return(0);
456	greg	1.9	while (*s) {
457	greg	1.5	ac = 0;
458			do {
459	greg	2.21	if (ac \|\| *s == '-')
460			av[ac++] = s;
461	greg	2.32	while (s && !isspace(s))
462	greg	1.5	s++;
463	greg	2.32	while (isspace(*s))
464	greg	1.5	s++;
465			} while (*s && ac < 4);
466			if ((na = getviewopt(vp, ac, av)) >= 0) {
467			if (na+1 < ac)
468			s = av[na+1];
469			nvopts++;
470	greg	1.9	} else if (ac > 1)
471			s = av[1];
472			}
473	greg	1.5	return(nvopts);
474	greg	1.1	}
475
476
477	greg	2.16	void
478	greg	2.35	fprintview( /* write out view parameters */
479			VIEW *vp,
480			FILE *fp
481			)
482	greg	1.1	{
483			fprintf(fp, " -vt%c", vp->type);
484			fprintf(fp, " -vp %.6g %.6g %.6g", vp->vp[0], vp->vp[1], vp->vp[2]);
485	greg	2.29	fprintf(fp, " -vd %.6g %.6g %.6g", vp->vdir[0]*vp->vdist,
486			vp->vdir[1]*vp->vdist,
487			vp->vdir[2]*vp->vdist);
488	greg	1.1	fprintf(fp, " -vu %.6g %.6g %.6g", vp->vup[0], vp->vup[1], vp->vup[2]);
489			fprintf(fp, " -vh %.6g -vv %.6g", vp->horiz, vp->vert);
490	greg	2.7	fprintf(fp, " -vo %.6g -va %.6g", vp->vfore, vp->vaft);
491	greg	1.9	fprintf(fp, " -vs %.6g -vl %.6g", vp->hoff, vp->voff);
492	greg	2.11	}
493
494
495			char *
496	greg	2.35	viewopt( /* translate to minimal view string */
497			VIEW *vp
498			)
499	greg	2.11	{
500			static char vwstr[128];
501	greg	2.36	char *cp = vwstr;
502	greg	2.11
503	greg	2.33	*cp = '\0';
504	greg	2.11	if (vp->type != stdview.type) {
505			sprintf(cp, " -vt%c", vp->type);
506			cp += strlen(cp);
507			}
508			if (!VEQ(vp->vp,stdview.vp)) {
509			sprintf(cp, " -vp %.6g %.6g %.6g",
510			vp->vp[0], vp->vp[1], vp->vp[2]);
511			cp += strlen(cp);
512			}
513	greg	2.29	if (!FEQ(vp->vdist,stdview.vdist) \|\| !VEQ(vp->vdir,stdview.vdir)) {
514	greg	2.11	sprintf(cp, " -vd %.6g %.6g %.6g",
515	greg	2.29	vp->vdir[0]*vp->vdist,
516			vp->vdir[1]*vp->vdist,
517			vp->vdir[2]*vp->vdist);
518	greg	2.11	cp += strlen(cp);
519			}
520			if (!VEQ(vp->vup,stdview.vup)) {
521			sprintf(cp, " -vu %.6g %.6g %.6g",
522			vp->vup[0], vp->vup[1], vp->vup[2]);
523			cp += strlen(cp);
524			}
525			if (!FEQ(vp->horiz,stdview.horiz)) {
526			sprintf(cp, " -vh %.6g", vp->horiz);
527			cp += strlen(cp);
528			}
529			if (!FEQ(vp->vert,stdview.vert)) {
530			sprintf(cp, " -vv %.6g", vp->vert);
531			cp += strlen(cp);
532			}
533			if (!FEQ(vp->vfore,stdview.vfore)) {
534			sprintf(cp, " -vo %.6g", vp->vfore);
535			cp += strlen(cp);
536			}
537			if (!FEQ(vp->vaft,stdview.vaft)) {
538			sprintf(cp, " -va %.6g", vp->vaft);
539			cp += strlen(cp);
540			}
541			if (!FEQ(vp->hoff,stdview.hoff)) {
542			sprintf(cp, " -vs %.6g", vp->hoff);
543			cp += strlen(cp);
544			}
545			if (!FEQ(vp->voff,stdview.voff)) {
546			sprintf(cp, " -vl %.6g", vp->voff);
547			cp += strlen(cp);
548			}
549			return(vwstr);
550	greg	1.1	}
551
552
553	greg	2.3	int
554	greg	2.35	isview( /* is this a view string? */
555			char *s
556			)
557	greg	2.3	{
558	greg	2.25	static char *altname[]={NULL,VIEWSTR,"rpict","rview","rvu","rpiece","pinterp",NULL};
559	greg	2.5	extern char *progname;
560	greg	2.36	char *cp;
561			char **an;
562	greg	2.3	/* add program name to list */
563	greg	2.5	if (altname[0] == NULL) {
564			for (cp = progname; *cp; cp++)
565			;
566			while (cp > progname && !ISDIRSEP(cp[-1]))
567			cp--;
568			altname[0] = cp;
569			}
570	greg	2.3	/* skip leading path */
571			cp = s;
572			while (cp && cp != ' ')
573			cp++;
574	greg	2.5	while (cp > s && !ISDIRSEP(cp[-1]))
575	greg	2.3	cp--;
576			for (an = altname; *an != NULL; an++)
577			if (!strncmp(an, cp, strlen(an)))
578			return(1);
579			return(0);
580			}
581	greg	1.1
582	greg	2.3
583	greg	1.15	struct myview {
584			VIEW *hv;
585			int ok;
586			};
587	greg	1.1
588	greg	1.15
589	gwlarson	2.14	static int
590	schorsch	2.26	gethview( /* get view from header */
591			char *s,
592			void *v
593			)
594	greg	1.1	{
595	schorsch	2.26	if (isview(s) && sscanview(((struct myview*)v)->hv, s) > 0)
596			((struct myview*)v)->ok++;
597	gwlarson	2.14	return(0);
598	greg	1.1	}
599
600
601			int
602	greg	2.35	viewfile( /* get view from file */
603			char *fname,
604			VIEW *vp,
605			RESOLU *rp
606			)
607	greg	1.1	{
608	greg	1.15	struct myview mvs;
609	greg	1.1	FILE *fp;
610
611	greg	2.16	if (fname == NULL \|\| !strcmp(fname, "-"))
612			fp = stdin;
613			else if ((fp = fopen(fname, "r")) == NULL)
614	greg	1.1	return(-1);
615
616	greg	1.15	mvs.hv = vp;
617			mvs.ok = 0;
618	greg	1.1
619	schorsch	2.26	getheader(fp, gethview, &mvs);
620	greg	1.8
621	greg	1.17	if (rp != NULL && !fgetsresolu(rp, fp))
622	greg	1.15	mvs.ok = 0;
623	greg	1.1
624			fclose(fp);
625
626	greg	1.15	return(mvs.ok);
627	greg	1.1	}