1 #include <u.h> 2 #include <libc.h> 3 #include "map.h" 4 5 static struct coord stdpar; 6 static double r0; 7 8 static Xbonne(struct place * place,double * x,double * y)9Xbonne(struct place *place, double *x, double *y) 10 { 11 double r, alpha; 12 r = r0 - place->nlat.l; 13 if(r<.001) 14 if(fabs(stdpar.c)<1e-10) 15 alpha = place->wlon.l; 16 else if(fabs(place->nlat.c)==0) 17 alpha = 0; 18 else 19 alpha = place->wlon.l/(1+ 20 stdpar.c*stdpar.c*stdpar.c/place->nlat.c/3); 21 else 22 alpha = place->wlon.l * place->nlat.c / r; 23 *x = - r*sin(alpha); 24 *y = - r*cos(alpha); 25 return(1); 26 } 27 28 proj bonne(double par)29bonne(double par) 30 { 31 if(fabs(par*RAD) < .01) 32 return(Xsinusoidal); 33 deg2rad(par, &stdpar); 34 r0 = stdpar.c/stdpar.s + stdpar.l; 35 return(Xbonne); 36 } 37