| #include <u.h> | |
| #include <libc.h> | |
| #include "map.h" | |
| static int | |
| Xmercator(struct place *place, double *x, double *y) | |
| { | |
| if(fabs(place->nlat.l) > 80.*RAD) | |
| return(-1); | |
| *x = -place->wlon.l; | |
| *y = 0.5*log((1+place->nlat.s)/(1-place->nlat.s)); | |
| return(1); | |
| } | |
| proj | |
| mercator(void) | |
| { | |
| return(Xmercator); | |
| } | |
| static double ecc = ECC; | |
| static int | |
| Xspmercator(struct place *place, double *x, double *y) | |
| { | |
| if(Xmercator(place,x,y) < 0) | |
| return(-1); | |
| *y += 0.5*ecc*log((1-ecc*place->nlat.s)/(1+ecc*place->nlat.s)); | |
| return(1); | |
| } | |
| proj | |
| sp_mercator(void) | |
| { | |
| return(Xspmercator); | |
| } |