landing.py 文件源码

def coords_down_bearing(lat, lon, bearing, distance, body):
        '''
        Takes a latitude, longitude and bearing in degrees, and a
        distance in meters over a given body.  Returns a tuple
        (latitude, longitude) of the point you've calculated.
        '''
        bearing = math.radians(bearing)
        R = body.equatorial_radius
        lat = math.radians(lat)
        lon = math.radians(lon)

        lat2 = math.asin( math.sin(lat)*math.cos(distance/R) +
                     math.cos(lat)*math.sin(distance/R)*math.cos(bearing))

        lon2 = lon + math.atan2(math.sin(bearing)*math.sin(distance/R
                        )*math.cos(lat),math.cos(distance/R)-math.sin(lat
                        )*math.sin(lat2))

        lat2 = math.degrees(lat2)
        lon2 = math.degrees(lon2)
        return (lat2, lon2)