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- #include <u.h>
- #include <libc.h>
- #include "map.h"
- static double r0, a;
- static int
- Xsimpleconic(struct place *place, double *x, double *y)
- {
- double r = r0 - place->nlat.l;
- double t = a*place->wlon.l;
- *x = -r*sin(t);
- *y = -r*cos(t);
- return 1;
- }
- proj
- simpleconic(double par0, double par1)
- {
- struct coord lat0;
- struct coord lat1;
- deg2rad(par0,&lat0);
- deg2rad(par1,&lat1);
- if(fabs(lat0.l+lat1.l)<.01)
- return rectangular(par0);
- if(fabs(lat0.l-lat1.l)<.01) {
- a = lat0.s/lat0.l;
- r0 = lat0.c/lat0.s + lat0.l;
- } else {
- a = (lat1.c-lat0.c)/(lat0.l-lat1.l);
- r0 = ((lat0.c+lat1.c)/a + lat1.l + lat0.l)/2;
- }
- return Xsimpleconic;
- }
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