Cesàro Fractal

最近在看How to think like a computer scientist:Learning with python这本书，下面是一个有趣的练习题：

用turtle module生成以下图形:

源代码如下：

import turtle

from math import radians

from math import sin



def cesaro(t, order, size):

    if order == 0:

        t.forward(size)

    else:

        s_size = size / 2 * (sin(radians(5)) + 1)

        for i in (85, -170, 85, 0):

            cesaro(t, order-1, s_size)

            t.left(i)



def square_cesaro(t, order, size):

    for i in range(4):

        cesaro(t, order, size)

        t.left(90)



screen = turtle.Screen()

screen.bgcolor("lightgreen")

t = turtle.Turtle()

t.color("blue")

square_cesaro(t, 3, 100)

screen.mainloop()

我想，只要是有规律的图形，再难也能用递归的方法画出来，是吗？