1 #include <u.h>
2 #include <libc.h>
3 #include "map.h"
4 
5 #define Xaitwist Xaitpole.nlat
6 static struct place Xaitpole;
7 
8 static int
9 Xaitoff(struct place *place, double *x, double *y)
10 {
11 	struct place p;
12 	copyplace(place,&p);
13 	p.wlon.l /= 2.;
14 	sincos(&p.wlon);
15 	norm(&p,&Xaitpole,&Xaitwist);
16 	Xazequalarea(&p,x,y);
17 	*x *= 2.;
18 	return(1);
19 }
20 
21 proj
22 aitoff(void)
23 {
24 	latlon(0.,0.,&Xaitpole);
25 	return(Xaitoff);
26 }