Jak centrować 'fillpoly'?

import cv2, numpy as np, os, sys

color = (255, 255, 255)
color2 = (0,0,0)

star = [(13, 101),(101,101), (128, 18),(151,101), (242, 101), (172,153), (198,236),(128,185), (57,236), (84,153)]

img = np.zeros((256, 256, 3), np.uint8)

x=2
new_star2 = tuple([list(map(lambda num: num // x, starx2)) for starx2 in star])
x2=4
new_star4 = tuple([list(map(lambda num: num // x2, starx3)) for starx3 in star])

cv2.fillPoly(img, np.array([star]), color)
cv2.imshow('window', img)

cv2.fillPoly(img, np.array([new_star2]), color2)
cv2.imshow('window1', img)

cv2.fillPoly(img, np.array([new_star4]), color)
cv2.imshow('window2', img)

cv2.waitKey(0)
cv2.destroyAllWindows()