4 #define PI 3.14159265358979323846
6 INLINE float deg2rad(float deg)
11 INLINE float rad2deg(float rad)
13 return rad * 180 / PI;
16 float distance(float lat1, float lon1, float lat2, float lon2);
17 int bearing(float lat1, float lon1, float lat2, float lon2);
18 const char *compass_heading(int bearing);
20 #endif /* COMPASS_H */