def METHOD_NAME(_obj, _event):
    global pts, pts2, time, time_incre, angular_frq, phase_angle, wavenumber
    time += incre_time
    cnt = next(counter)
    x, y, z = update_coordinates(wavenumber, angular_frq, phase_angle, time)
    pts = np.array([(a, b, c) for (a, b, c) in zip(x, y, z)])
    vertices[:] = initial_vertices + np.repeat(pts, no_vertices_per_point, axis=0)
    utils.update_actor(wave_actor1)
    xx, zz, yy = update_coordinates(wavenumber, angular_frq, phase_angle, time)
    pts2 = np.array([(a, b, c) for (a, b, c) in zip(xx, yy, zz)])
    vertices2[:] = initial_vertices2 + np.repeat(pts2, no_vertices_per_point2, axis=0)
    utils.update_actor(wave_actor2)
    showm.render()
    # to end the animation
    if cnt == end:
        showm.exit()