public AltosGreatCircle (double start_lat, double start_lon,
double end_lat, double end_lon) {
this(start_lat, start_lon, 0, end_lat, end_lon, 0);
public AltosGreatCircle (double start_lat, double start_lon,
double end_lat, double end_lon) {
this(start_lat, start_lon, 0, end_lat, end_lon, 0);