from turtle import *
from random import random,randint
screen = Screen()
width ,height = 800,600
screen.setup(width,height)
screen.title("模拟3D星空")
screen.bgcolor("black")
screen.mode("logo")
screen.delay(0)#这里要设为0，否则很卡
t = Turtle(visible = False,shape='circle')
t.pencolor("white")
t.fillcolor("white")
t.penup()
t.setheading(-90)
t.goto(width/2,randint(-height/2,height/2))
stars = []
for i in range(200):
star = t.clone()
s =random() /3
star.shapesize(s,s)
star.speed(int(s*10))
star.setx(width/2 + randint(1,width))
star.sety( randint(-height/2,height/2))
star.showturtle()
stars.append(star)
while True:
for star in stars:
star.setx(star.xcor() - 3 * star.speed())
if star.xcor()<-width/2:
star.hideturtle()
star.setx(width/2 + randint(1,width))
star.sety( randint(-height/2,height/2))
star.showturtle()
