/*  * This file is part of the UCB release of Plan 9. It is subject to the license * terms in the LICENSE file found in the top-level directory of this * distribution and at http://akaros.cs.berkeley.edu/files/Plan9License. No * part of the UCB release of Plan 9, including this file, may be copied, * modified, propagated, or distributed except according to the terms contained * in the LICENSE file. */ #include <u.h>#include <libc.h>#include "map.h" struct coord center; static intXelliptic(struct place *place, double *x, double *y){	double r1,r2;	r1 = acos(place->nlat.c*(place->wlon.c*center.c		- place->wlon.s*center.s));	r2 = acos(place->nlat.c*(place->wlon.c*center.c		+ place->wlon.s*center.s));	*x = -(r1*r1 - r2*r2)/(4*center.l);	*y = (r1*r1+r2*r2)/2 - (center.l*center.l+*x**x);	if(*y < 0)		*y = 0;	*y = sqrt(*y);	if(place->nlat.l<0)		*y = -*y;	return(1);} projelliptic(double l){	l = fabs(l);	if(l>89)		return(0);	if(l<1)		return(Xazequidistant);	deg2rad(l,&center);	return(Xelliptic);}