YNOTES笔记

#Python Turtle - Spirograph - www.101computing.net/python-turtle-spirograph/
import turtle
from math import cos,sin
from time import sleep

window = turtle.Screen()
window.bgcolor("#FFFFFF")

mySpirograph = turtle.Turtle()
mySpirograph.hideturtle()
mySpirograph.tracer(0)
mySpirograph.speed(0)
mySpirograph.pensize(2)

myPen = turtle.Turtle()
myPen.hideturtle()
myPen.tracer(0)
myPen.speed(0)
myPen.pensize(3)
myPen.color("#AA00AA")

R = 125
r = 75
d = 125

angle = 0

myPen.penup()
myPen.goto(R-r+d,0)
myPen.pendown()

theta = 0.2
steps = int(6*3.14/theta)

for t in range(0,steps):
    mySpirograph.clear()
    mySpirograph.penup()
    mySpirograph.setheading(0)
    mySpirograph.goto(0,-R)
    mySpirograph.color("#999999")
    mySpirograph.pendown()
    mySpirograph.circle(R)
    angle+=theta
    
    x = (R - r) * cos(angle)
    y = (R - r) * sin(angle)
    mySpirograph.penup()
    mySpirograph.goto(x,y-r)
    mySpirograph.color("#222222")
    mySpirograph.pendown()
    mySpirograph.circle(r)
    mySpirograph.penup()
    mySpirograph.goto(x,y)
    mySpirograph.dot(5)
    
    x = (R - r) * cos(angle) + d * cos(((R-r)/r)*angle)
    y = (R - r) * sin(angle) - d * sin(((R-r)/r)*angle)
    mySpirograph.pendown()
    mySpirograph.goto(x,y)
    #mySpirograph.setheading((R-r)*degrees(angle)/r)
    #mySpirograph.forward(d)
    mySpirograph.dot(5)
    myPen.goto(mySpirograph.pos())
    
    mySpirograph.getscreen().update() 
    sleep(0.05)

sleep(0.5)
#Hide Spirograph
mySpirograph.clear()
mySpirograph.getscreen().update()