git: 9front

ref: 4f4a7afe98b8bd09f20db27200728fa5f0109323
dir: /sys/src/cmd/map/libmap/azequalarea.c/

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#include <u.h>
#include <libc.h>
#include "map.h"

int
Xazequalarea(struct place *place, double *x, double *y)
{
	double r;
	r = sqrt(1. - place->nlat.s);
	*x = - r * place->wlon.s;
	*y = - r * place->wlon.c;
	return(1);
}

proj
azequalarea(void)
{
	return(Xazequalarea);
}