patterns — band

def g04_band(rng):
    """Warped radial field posterised into hard bands."""
    steps = rng.randint(5, 8)
    c = Canvas(rng.choice([30, 40]), _pal(rng), steps, "band", "mosaic")
    c.ground_from(Field(rng, "radial", warp=rng.uniform(0.3, 0.6), steps=steps))
    return c