src/common/image.c

#ifndef lint
static const char       RCSid[] = "$Id: image.c,v 2.30 2005/02/07 20:13:55 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 (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;
        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]);
                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(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->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(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 (!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(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:	2.31
Committed:	Fri Feb 18 17:42:14 2005 UTC (19 years, 2 months ago) by greg
Content type:	text/plain
Branch:	MAIN
CVS Tags:	rad3R7P2, rad3R7P1
Changes since 2.30:	+3 -1 lines
Log Message:	Added check for illegal view distance
#	User	Rev	Content
1	greg	1.1	#ifndef lint
2	greg	2.31	static const char RCSid[] = "$Id: image.c,v 2.30 2005/02/07 20:13:55 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	2.31	if (v->vdist <= FTINY)
38			return("illegal view distance");
39	greg	2.29	v->vdist = normalize(v->vdir); / normalize direction */
40			if (v->vdist == 0.0)
41	greg	1.1	return("zero view direction");
42
43	greg	1.14	if (normalize(v->vup) == 0.0) /* normalize view up */
44			return("zero view up vector");
45
46	greg	1.5	fcross(v->hvec, v->vdir, v->vup); /* compute horiz dir */
47
48			if (normalize(v->hvec) == 0.0)
49	greg	1.14	return("view up parallel to view direction");
50	greg	1.1
51	greg	1.5	fcross(v->vvec, v->hvec, v->vdir); /* compute vert dir */
52
53	greg	1.12	if (v->horiz <= FTINY)
54			return(ill_horiz);
55			if (v->vert <= FTINY)
56			return(ill_vert);
57
58			switch (v->type) {
59			case VT_PAR: /* parallel view */
60	greg	1.5	v->hn2 = v->horiz;
61	greg	1.12	v->vn2 = v->vert;
62			break;
63			case VT_PER: /* perspective view */
64			if (v->horiz >= 180.0-FTINY)
65			return(ill_horiz);
66			if (v->vert >= 180.0-FTINY)
67			return(ill_vert);
68	greg	1.5	v->hn2 = 2.0 * tan(v->horiz*(PI/180.0/2.0));
69	greg	1.12	v->vn2 = 2.0 * tan(v->vert*(PI/180.0/2.0));
70			break;
71	greg	2.9	case VT_CYL: /* cylindrical panorama */
72			if (v->horiz > 360.0+FTINY)
73			return(ill_horiz);
74			if (v->vert >= 180.0-FTINY)
75			return(ill_vert);
76			v->hn2 = v->horiz * (PI/180.0);
77			v->vn2 = 2.0 * tan(v->vert*(PI/180.0/2.0));
78			break;
79	greg	1.12	case VT_ANG: /* angular fisheye */
80			if (v->horiz > 360.0+FTINY)
81			return(ill_horiz);
82			if (v->vert > 360.0+FTINY)
83			return(ill_vert);
84	greg	2.9	v->hn2 = v->horiz * (PI/180.0);
85			v->vn2 = v->vert * (PI/180.0);
86	greg	1.12	break;
87			case VT_HEM: /* hemispherical fisheye */
88			if (v->horiz > 180.0+FTINY)
89			return(ill_horiz);
90			if (v->vert > 180.0+FTINY)
91			return(ill_vert);
92			v->hn2 = 2.0 * sin(v->horiz*(PI/180.0/2.0));
93			v->vn2 = 2.0 * sin(v->vert*(PI/180.0/2.0));
94			break;
95			default:
96	greg	1.1	return("unknown view type");
97	greg	1.12	}
98	greg	1.13	if (v->type != VT_ANG) {
99	greg	2.9	if (v->type != VT_CYL) {
100			v->hvec[0] *= v->hn2;
101			v->hvec[1] *= v->hn2;
102			v->hvec[2] *= v->hn2;
103			}
104	greg	1.12	v->vvec[0] *= v->vn2;
105			v->vvec[1] *= v->vn2;
106			v->vvec[2] *= v->vn2;
107			}
108	greg	1.5	v->hn2 *= v->hn2;
109			v->vn2 *= v->vn2;
110	greg	1.1
111			return(NULL);
112			}
113
114
115	greg	2.16	void
116	greg	1.7	normaspect(va, ap, xp, yp) /* fix pixel aspect or resolution */
117			double va; /* view aspect ratio */
118			double ap; / pixel aspect in (or out if 0) */
119			int xp, yp; /* x and y resolution in (or out if ap!=0) /
120	greg	1.6	{
121			if (*ap <= FTINY)
122	greg	1.7	ap = va xp / yp; /* compute pixel aspect */
123	greg	1.6	else if (va * xp > ap * *yp)
124	greg	1.10	xp = yp / va * ap + .5; / reduce x resolution */
125	greg	1.6	else
126	greg	1.10	yp = xp * va / ap + .5; / reduce y resolution */
127	greg	1.6	}
128
129
130	greg	2.7	double
131	greg	1.5	viewray(orig, direc, v, x, y) /* compute ray origin and direction */
132	greg	1.1	FVECT orig, direc;
133			register VIEW *v;
134			double x, y;
135			{
136	greg	1.12	double d, z;
137
138	greg	1.5	x += v->hoff - 0.5;
139			y += v->voff - 0.5;
140	greg	1.1
141	greg	1.12	switch(v->type) {
142			case VT_PAR: /* parallel view */
143	greg	2.7	orig[0] = v->vp[0] + v->vfore*v->vdir[0]
144			+ xv->hvec[0] + yv->vvec[0];
145			orig[1] = v->vp[1] + v->vfore*v->vdir[1]
146			+ xv->hvec[1] + yv->vvec[1];
147			orig[2] = v->vp[2] + v->vfore*v->vdir[2]
148			+ xv->hvec[2] + yv->vvec[2];
149	greg	1.1	VCOPY(direc, v->vdir);
150	greg	2.8	return(v->vaft > FTINY ? v->vaft - v->vfore : 0.0);
151	greg	1.12	case VT_PER: /* perspective view */
152	greg	1.5	direc[0] = v->vdir[0] + xv->hvec[0] + yv->vvec[0];
153			direc[1] = v->vdir[1] + xv->hvec[1] + yv->vvec[1];
154			direc[2] = v->vdir[2] + xv->hvec[2] + yv->vvec[2];
155	greg	2.7	orig[0] = v->vp[0] + v->vfore*direc[0];
156			orig[1] = v->vp[1] + v->vfore*direc[1];
157			orig[2] = v->vp[2] + v->vfore*direc[2];
158			d = normalize(direc);
159	greg	2.8	return(v->vaft > FTINY ? (v->vaft - v->vfore)*d : 0.0);
160	greg	1.12	case VT_HEM: /* hemispherical fisheye */
161	greg	1.13	z = 1.0 - xxv->hn2 - yyv->vn2;
162	greg	1.12	if (z < 0.0)
163	greg	2.7	return(-1.0);
164	greg	1.12	z = sqrt(z);
165			direc[0] = zv->vdir[0] + xv->hvec[0] + y*v->vvec[0];
166			direc[1] = zv->vdir[1] + xv->hvec[1] + y*v->vvec[1];
167			direc[2] = zv->vdir[2] + xv->hvec[2] + y*v->vvec[2];
168	greg	2.7	orig[0] = v->vp[0] + v->vfore*direc[0];
169			orig[1] = v->vp[1] + v->vfore*direc[1];
170			orig[2] = v->vp[2] + v->vfore*direc[2];
171	greg	2.8	return(v->vaft > FTINY ? v->vaft - v->vfore : 0.0);
172	greg	2.9	case VT_CYL: /* cylindrical panorama */
173			d = x * v->horiz * (PI/180.0);
174			z = cos(d);
175			x = sin(d);
176			direc[0] = zv->vdir[0] + xv->hvec[0] + y*v->vvec[0];
177			direc[1] = zv->vdir[1] + xv->hvec[1] + y*v->vvec[1];
178			direc[2] = zv->vdir[2] + xv->hvec[2] + y*v->vvec[2];
179			orig[0] = v->vp[0] + v->vfore*direc[0];
180			orig[1] = v->vp[1] + v->vfore*direc[1];
181			orig[2] = v->vp[2] + v->vfore*direc[2];
182			d = normalize(direc);
183			return(v->vaft > FTINY ? (v->vaft - v->vfore)*d : 0.0);
184	greg	1.12	case VT_ANG: /* angular fisheye */
185			x *= v->horiz/180.0;
186			y *= v->vert/180.0;
187			d = xx + yy;
188			if (d > 1.0)
189	greg	2.7	return(-1.0);
190	greg	1.12	d = sqrt(d);
191			z = cos(PI*d);
192	greg	2.6	d = d <= FTINY ? PI : sqrt(1 - z*z)/d;
193	greg	1.12	x *= d;
194			y *= d;
195			direc[0] = zv->vdir[0] + xv->hvec[0] + y*v->vvec[0];
196			direc[1] = zv->vdir[1] + xv->hvec[1] + y*v->vvec[1];
197			direc[2] = zv->vdir[2] + xv->hvec[2] + y*v->vvec[2];
198	greg	2.7	orig[0] = v->vp[0] + v->vfore*direc[0];
199			orig[1] = v->vp[1] + v->vfore*direc[1];
200			orig[2] = v->vp[2] + v->vfore*direc[2];
201	greg	2.8	return(v->vaft > FTINY ? v->vaft - v->vfore : 0.0);
202	greg	1.1	}
203	greg	2.7	return(-1.0);
204	greg	1.1	}
205
206
207	greg	2.16	void
208	greg	1.17	viewloc(ip, v, p) /* find image location for point */
209			FVECT ip;
210	greg	1.3	register VIEW *v;
211			FVECT p;
212			{
213	gregl	2.13	double d, d2;
214	greg	1.3	FVECT disp;
215	greg	1.5
216	greg	1.3	disp[0] = p[0] - v->vp[0];
217			disp[1] = p[1] - v->vp[1];
218			disp[2] = p[2] - v->vp[2];
219
220	greg	1.12	switch (v->type) {
221			case VT_PAR: /* parallel view */
222	greg	2.7	ip[2] = DOT(disp,v->vdir) - v->vfore;
223	greg	1.13	break;
224	greg	1.12	case VT_PER: /* perspective view */
225	greg	1.11	d = DOT(disp,v->vdir);
226	gregl	2.13	ip[2] = VLEN(disp);
227	greg	1.17	if (d < 0.0) { /* fold pyramid */
228			ip[2] = -ip[2];
229	greg	1.11	d = -d;
230	greg	2.7	}
231			if (d > FTINY) {
232	greg	1.11	d = 1.0/d;
233			disp[0] *= d;
234			disp[1] *= d;
235			disp[2] *= d;
236			}
237	greg	2.7	ip[2] = (1.0 - v->vfored);
238	greg	1.13	break;
239	greg	1.12	case VT_HEM: /* hemispherical fisheye */
240			d = normalize(disp);
241	greg	1.17	if (DOT(disp,v->vdir) < 0.0)
242			ip[2] = -d;
243			else
244			ip[2] = d;
245	greg	2.7	ip[2] -= v->vfore;
246	greg	1.13	break;
247	greg	2.9	case VT_CYL: /* cylindrical panorama */
248			d = DOT(disp,v->hvec);
249	gregl	2.13	d2 = DOT(disp,v->vdir);
250			ip[0] = 180.0/PI * atan2(d,d2) / v->horiz + 0.5 - v->hoff;
251			d = 1.0/sqrt(dd + d2d2);
252			ip[1] = DOT(disp,v->vvec)*d/v->vn2 + 0.5 - v->voff;
253			ip[2] = VLEN(disp);
254	gwlarson	2.15	ip[2] = (1.0 - v->vfored);
255	greg	2.9	return;
256	greg	1.12	case VT_ANG: /* angular fisheye */
257	greg	1.17	ip[0] = 0.5 - v->hoff;
258			ip[1] = 0.5 - v->voff;
259	greg	2.7	ip[2] = normalize(disp) - v->vfore;
260	greg	1.12	d = DOT(disp,v->vdir);
261			if (d >= 1.0-FTINY)
262			return;
263			if (d <= -(1.0-FTINY)) {
264	greg	2.7	ip[0] += 180.0/v->horiz;
265	greg	1.12	return;
266			}
267			d = acos(d)/PI / sqrt(1.0 - d*d);
268	greg	1.17	ip[0] += DOT(disp,v->hvec)d180.0/v->horiz;
269			ip[1] += DOT(disp,v->vvec)d180.0/v->vert;
270	greg	1.12	return;
271	greg	1.3	}
272	greg	1.17	ip[0] = DOT(disp,v->hvec)/v->hn2 + 0.5 - v->hoff;
273			ip[1] = DOT(disp,v->vvec)/v->vn2 + 0.5 - v->voff;
274	greg	1.3	}
275
276
277	greg	2.16	void
278	greg	1.17	pix2loc(loc, rp, px, py) /* compute image location from pixel pos. */
279	schorsch	2.18	RREAL loc[2];
280	greg	1.17	register RESOLU *rp;
281			int px, py;
282			{
283			register int x, y;
284
285	greg	2.16	if (rp->rt & YMAJOR) {
286	greg	1.17	x = px;
287			y = py;
288			} else {
289			x = py;
290			y = px;
291			}
292	greg	2.16	if (rp->rt & XDECR)
293	greg	1.17	x = rp->xr-1 - x;
294	greg	2.16	if (rp->rt & YDECR)
295	greg	1.17	y = rp->yr-1 - y;
296			loc[0] = (x+.5)/rp->xr;
297			loc[1] = (y+.5)/rp->yr;
298			}
299
300
301	greg	2.16	void
302	greg	1.17	loc2pix(pp, rp, lx, ly) /* compute pixel pos. from image location */
303			int pp[2];
304			register RESOLU *rp;
305			double lx, ly;
306			{
307			register int x, y;
308
309			x = lx * rp->xr;
310			y = ly * rp->yr;
311	greg	2.16	if (rp->rt & XDECR)
312	greg	1.17	x = rp->xr-1 - x;
313	greg	2.16	if (rp->rt & YDECR)
314	greg	1.17	y = rp->yr-1 - y;
315	greg	2.16	if (rp->rt & YMAJOR) {
316	greg	1.17	pp[0] = x;
317			pp[1] = y;
318			} else {
319			pp[0] = y;
320			pp[1] = x;
321			}
322			}
323
324
325	greg	1.5	int
326			getviewopt(v, ac, av) /* process view argument */
327			register VIEW *v;
328			int ac;
329			register char *av[];
330			{
331	greg	1.16	#define check(c,l) if ((av[0][c]&&av[0][c]!=' ') \|\| \
332			badarg(ac-1,av+1,l)) return(-1)
333	greg	1.5
334	greg	1.9	if (ac <= 0 \|\| av[0][0] != '-' \|\| av[0][1] != 'v')
335	greg	1.5	return(-1);
336			switch (av[0][2]) {
337			case 't': /* type */
338			if (!av[0][3] \|\| av[0][3]==' ')
339			return(-1);
340	greg	1.16	check(4,"");
341	greg	1.5	v->type = av[0][3];
342			return(0);
343			case 'p': /* point */
344	greg	1.16	check(3,"fff");
345	greg	1.5	v->vp[0] = atof(av[1]);
346			v->vp[1] = atof(av[2]);
347			v->vp[2] = atof(av[3]);
348			return(3);
349			case 'd': /* direction */
350	greg	1.16	check(3,"fff");
351	greg	1.5	v->vdir[0] = atof(av[1]);
352			v->vdir[1] = atof(av[2]);
353			v->vdir[2] = atof(av[3]);
354	greg	2.30	v->vdist = 1.;
355	greg	1.5	return(3);
356			case 'u': /* up */
357	greg	1.16	check(3,"fff");
358	greg	1.5	v->vup[0] = atof(av[1]);
359			v->vup[1] = atof(av[2]);
360			v->vup[2] = atof(av[3]);
361			return(3);
362			case 'h': /* horizontal size */
363	greg	1.16	check(3,"f");
364	greg	1.5	v->horiz = atof(av[1]);
365			return(1);
366			case 'v': /* vertical size */
367	greg	1.16	check(3,"f");
368	greg	1.5	v->vert = atof(av[1]);
369			return(1);
370	greg	2.7	case 'o': /* fore clipping plane */
371			check(3,"f");
372			v->vfore = atof(av[1]);
373			return(1);
374			case 'a': /* aft clipping plane */
375			check(3,"f");
376			v->vaft = atof(av[1]);
377			return(1);
378	greg	1.5	case 's': /* shift */
379	greg	1.16	check(3,"f");
380	greg	1.5	v->hoff = atof(av[1]);
381			return(1);
382			case 'l': /* lift */
383	greg	1.16	check(3,"f");
384	greg	1.5	v->voff = atof(av[1]);
385			return(1);
386			default:
387			return(-1);
388			}
389			#undef check
390			}
391
392
393			int
394			sscanview(vp, s) /* get view parameters from string */
395			VIEW *vp;
396	greg	1.1	register char *s;
397			{
398	greg	1.5	int ac;
399			char *av[4];
400			int na;
401			int nvopts = 0;
402
403	greg	2.20	while (*s == ' ')
404	greg	2.19	s++;
405	greg	2.20	if (*s != '-')
406			s = sskip2(s,1);
407	greg	1.9	while (*s) {
408	greg	1.5	ac = 0;
409			do {
410	greg	2.21	if (ac \|\| *s == '-')
411			av[ac++] = s;
412	greg	1.5	while (s && s != ' ')
413			s++;
414			while (*s == ' ')
415			s++;
416			} while (*s && ac < 4);
417			if ((na = getviewopt(vp, ac, av)) >= 0) {
418			if (na+1 < ac)
419			s = av[na+1];
420			nvopts++;
421	greg	1.9	} else if (ac > 1)
422			s = av[1];
423			}
424	greg	1.5	return(nvopts);
425	greg	1.1	}
426
427
428	greg	2.16	void
429	greg	1.1	fprintview(vp, fp) /* write out view parameters */
430			register VIEW *vp;
431			FILE *fp;
432			{
433			fprintf(fp, " -vt%c", vp->type);
434			fprintf(fp, " -vp %.6g %.6g %.6g", vp->vp[0], vp->vp[1], vp->vp[2]);
435	greg	2.29	fprintf(fp, " -vd %.6g %.6g %.6g", vp->vdir[0]*vp->vdist,
436			vp->vdir[1]*vp->vdist,
437			vp->vdir[2]*vp->vdist);
438	greg	1.1	fprintf(fp, " -vu %.6g %.6g %.6g", vp->vup[0], vp->vup[1], vp->vup[2]);
439			fprintf(fp, " -vh %.6g -vv %.6g", vp->horiz, vp->vert);
440	greg	2.7	fprintf(fp, " -vo %.6g -va %.6g", vp->vfore, vp->vaft);
441	greg	1.9	fprintf(fp, " -vs %.6g -vl %.6g", vp->hoff, vp->voff);
442	greg	2.11	}
443
444
445			char *
446			viewopt(vp) /* translate to minimal view string */
447			register VIEW *vp;
448			{
449			static char vwstr[128];
450			register char *cp = vwstr;
451
452			if (vp->type != stdview.type) {
453			sprintf(cp, " -vt%c", vp->type);
454			cp += strlen(cp);
455			}
456			if (!VEQ(vp->vp,stdview.vp)) {
457			sprintf(cp, " -vp %.6g %.6g %.6g",
458			vp->vp[0], vp->vp[1], vp->vp[2]);
459			cp += strlen(cp);
460			}
461	greg	2.29	if (!FEQ(vp->vdist,stdview.vdist) \|\| !VEQ(vp->vdir,stdview.vdir)) {
462	greg	2.11	sprintf(cp, " -vd %.6g %.6g %.6g",
463	greg	2.29	vp->vdir[0]*vp->vdist,
464			vp->vdir[1]*vp->vdist,
465			vp->vdir[2]*vp->vdist);
466	greg	2.11	cp += strlen(cp);
467			}
468			if (!VEQ(vp->vup,stdview.vup)) {
469			sprintf(cp, " -vu %.6g %.6g %.6g",
470			vp->vup[0], vp->vup[1], vp->vup[2]);
471			cp += strlen(cp);
472			}
473			if (!FEQ(vp->horiz,stdview.horiz)) {
474			sprintf(cp, " -vh %.6g", vp->horiz);
475			cp += strlen(cp);
476			}
477			if (!FEQ(vp->vert,stdview.vert)) {
478			sprintf(cp, " -vv %.6g", vp->vert);
479			cp += strlen(cp);
480			}
481			if (!FEQ(vp->vfore,stdview.vfore)) {
482			sprintf(cp, " -vo %.6g", vp->vfore);
483			cp += strlen(cp);
484			}
485			if (!FEQ(vp->vaft,stdview.vaft)) {
486			sprintf(cp, " -va %.6g", vp->vaft);
487			cp += strlen(cp);
488			}
489			if (!FEQ(vp->hoff,stdview.hoff)) {
490			sprintf(cp, " -vs %.6g", vp->hoff);
491			cp += strlen(cp);
492			}
493			if (!FEQ(vp->voff,stdview.voff)) {
494			sprintf(cp, " -vl %.6g", vp->voff);
495			cp += strlen(cp);
496			}
497			return(vwstr);
498	greg	1.1	}
499
500
501	greg	2.3	int
502			isview(s) /* is this a view string? */
503			char *s;
504			{
505	greg	2.25	static char *altname[]={NULL,VIEWSTR,"rpict","rview","rvu","rpiece","pinterp",NULL};
506	greg	2.5	extern char *progname;
507	greg	2.3	register char *cp;
508			register char **an;
509			/* add program name to list */
510	greg	2.5	if (altname[0] == NULL) {
511			for (cp = progname; *cp; cp++)
512			;
513			while (cp > progname && !ISDIRSEP(cp[-1]))
514			cp--;
515			altname[0] = cp;
516			}
517	greg	2.3	/* skip leading path */
518			cp = s;
519			while (cp && cp != ' ')
520			cp++;
521	greg	2.5	while (cp > s && !ISDIRSEP(cp[-1]))
522	greg	2.3	cp--;
523			for (an = altname; *an != NULL; an++)
524			if (!strncmp(an, cp, strlen(an)))
525			return(1);
526			return(0);
527			}
528	greg	1.1
529	greg	2.3
530	greg	1.15	struct myview {
531			VIEW *hv;
532			int ok;
533			};
534	greg	1.1
535	greg	1.15
536	gwlarson	2.14	static int
537	schorsch	2.26	gethview( /* get view from header */
538			char *s,
539			void *v
540			)
541	greg	1.1	{
542	schorsch	2.26	if (isview(s) && sscanview(((struct myview*)v)->hv, s) > 0)
543			((struct myview*)v)->ok++;
544	gwlarson	2.14	return(0);
545	greg	1.1	}
546
547
548			int
549	greg	1.17	viewfile(fname, vp, rp) /* get view from file */
550	greg	1.1	char *fname;
551			VIEW *vp;
552	greg	1.17	RESOLU *rp;
553	greg	1.1	{
554	greg	1.15	struct myview mvs;
555	greg	1.1	FILE *fp;
556
557	greg	2.16	if (fname == NULL \|\| !strcmp(fname, "-"))
558			fp = stdin;
559			else if ((fp = fopen(fname, "r")) == NULL)
560	greg	1.1	return(-1);
561
562	greg	1.15	mvs.hv = vp;
563			mvs.ok = 0;
564	greg	1.1
565	schorsch	2.26	getheader(fp, gethview, &mvs);
566	greg	1.8
567	greg	1.17	if (rp != NULL && !fgetsresolu(rp, fp))
568	greg	1.15	mvs.ok = 0;
569	greg	1.1
570			fclose(fp);
571
572	greg	1.15	return(mvs.ok);
573	greg	1.1	}