figure = fpl.Figure(size=(700, 700))

start, stop, step = 0, 2 * np.pi, 0.4

# get uniform x, y positions
x, y = np.meshgrid(np.arange(start, stop, step), np.arange(start, stop, step))

# vectors, u and v are x and y components indication directions
u = np.cos(x)
v = np.sin(y)

# positions of each vector as [n_points, 2] array
positions = np.column_stack([x.ravel(), y.ravel()])
# directions of each vector as a [n_points, 2] array
directions = np.column_stack([u.ravel(), v.ravel()])


vector_field = figure[0, 0].add_vector_field(
    positions=positions,
    directions=directions,
)

def update(change):
    val = change["new"]
    start, stop, step = 0, 2 * np.pi, 0.4
    start += val
    stop += val
    
    # get uniform x, y positions
    x, y = np.meshgrid(np.arange(start, stop, step), np.arange(start, stop, step))
    
    # vectors, u and v are x and y components indication directions
    u = np.cos(x)
    v = np.sin(y)
    
    directions = np.column_stack([u.ravel(), v.ravel()])
    
    vector_field.directions = directions

slider = FloatSlider(value=0, min=-5, max=5, step=0.01)
slider.observe(update, "value")

VBox([figure.show(), slider])