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- #include <u.h>
- #include <libc.h>
- #include "map.h"
- static double scale;
- static int
- Xgall(struct place *place, double *x, double *y)
- {
- /* two ways to compute tan(place->nlat.l/2) */
- if(fabs(place->nlat.s)<.1)
- *y = sin(place->nlat.l/2)/cos(place->nlat.l/2);
- else
- *y = (1-place->nlat.c)/place->nlat.s;
- *x = -scale*place->wlon.l;
- return 1;
- }
- proj
- gall(double par)
- {
- double coshalf;
- if(fabs(par)>80)
- return 0;
- par *= RAD;
- coshalf = cos(par/2);
- scale = cos(par)/(2*coshalf*coshalf);
- return Xgall;
- }
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