def format_coord(*args):
    phi = self.trackball.phi
    theta = self.trackball.theta
    return ('Θ : %.1f, ɸ: %.1f' % (theta, phi))
def format_coord(*args):
    phi = self.trackball.phi
    theta = self.trackball.theta
    return ('Θ : %.1f, ɸ: %.1f' % (theta, phi))