NAME sphere2xy FUNCTION sphere2xy(r, x, y, z) NOTES Convert x, y, z on a sphere object with radius r to longitude and latitude in degree. INPUTS x, y, x - coordinate OUTPUTS longitude (0 to 360) and latitude (-90 to 90) in degree. SOURCE function sphere2xy(r, x, y, z) local c = 57.29577951 lat = c * math.asin(z/r) r = math.sqrt(x*x + y*y) + 1.e-15 lon = c * math.acos(x/r) if y < 0 then lon = 360 - lon end return lon, lat end