import math


def ellipse(t, center, a, b):
    """ compute points on an elliplse, with t running from 0 to 2*math.pi, a
    and b being the radii and center as the origin of the ellipse. """
    xcenter, ycenter = center
    return int(xcenter - a / 2.0 * math.sin(t)), int(ycenter - b / 2.0 * math.cos(t))