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#include <u.h>#include <libc.h>#include "map.h"/* refractive fisheye, not logarithmic */ static double n; static intXfisheye(struct place *place, double *x, double *y){	double r;	double u = sin(PI/4-place->nlat.l/2)/n;	if(fabs(u) > .97)		return -1;	r = tan(asin(u));	*x = -r*place->wlon.s;	*y = -r*place->wlon.c;	return 1;} projfisheye(double par){	n = par;	return n<.1? 0: Xfisheye;}