python中的乌龟内圈边界

Question

好吧，我整天都在做这件事，但一点头绪都没有。我需要让我的海龟对象在圆的外画出随机线。

我之前编写了将随机线限制在边界内的代码，所以我认为我所要做的就是更改符号，但这不起作用。我不允许使用坐标几何 - 它必须是更基本的东西......

这是我当前格式的代码：

import turtle, random
mRoshi = turtle.Turtle()

def draw_any_shape(myTurtle, sideLength, numSides):
    turnAng = 360/numSides
    for i in range(numSides):
        myTurtle.forward(sideLength)
        myTurtle.right(turnAng)

def drawCircle(myTurtle, radius, startX, startY):
    circumference = 2*3.1415*radius
    sideLength = circumference/360
    myTurtle.penup()
    myTurtle.goto(startX, startY)
    #myTurtle.dot()
    myTurtle.goto(startX, startY+radius)
    myTurtle.pendown()
    draw_any_shape(myTurtle, sideLength, 360)


def stumblingTurtle(myTurtle, radius, startX, startY, paramN5):
    circumference = 2*3.1415*radius
    myTurtle.speed(6)
    drawCircle(myTurtle, radius, startX, startY)
    myTurtle.penup()
    for i in range(paramN5):
        drx = random.randint(-800, 800)
        drw = random.randint(-800, 800)
        if (drx**2 + drw**2) > radius**2:
            myTurtle.goto(drx,drw)
        crx = random.randint(-800, 800)
        crw = random.randint(-800, 800)
        xdif = crx-drx
        ydif = crw-drw
        for j in range(drx, crx):
            for k in range(drw, crw):
                if (xdif**2 + ydif**2) > radius**2:
                    myTurtle.goto(crx,crw)

Answer 1

这是你想要的吗？它也基于最初kept the turtle within a circle 的代码。它使用 Python3 乌龟的 undo 能力让乌龟意外地游走在圆圈中，然后像从未发生过一样撤消该意外：

import turtle
import random

RADIUS = 50
MAXIMUM_TURN = 45
STEP_SIZE = 10
BORDER = 20

def bounded_random_move():

    yertle.forward(STEP_SIZE)

    x, y = yertle.position()

    if (x * x + y * y) < RADIUS * RADIUS or x < -window_width/2 or x > window_width/2 or y < -window_height/2 or y > window_height/2:
        yertle.undo()  # undo misstep
        turn = random.randint(180 - MAXIMUM_TURN, 180 + MAXIMUM_TURN)
        yertle.left(turn)

    turtle.ontimer(bounded_random_move, 100)

turtle.setup(RADIUS * 10, RADIUS * 10)

window_width = turtle.window_width() - BORDER
window_height = turtle.window_height() - BORDER

magic_marker = turtle.Turtle(visible=False)
magic_marker.penup()
magic_marker.color("red")
magic_marker.sety(-RADIUS)
magic_marker.pendown()
magic_marker.circle(RADIUS)

yertle = turtle.Turtle(shape="turtle", visible=False)
yertle.speed("fastest")
yertle.penup()
yertle.goto(RADIUS * 2, RADIUS * 2)  # start outside circle
yertle.pendown()
yertle.showturtle()

turtle.ontimer(bounded_random_move, 100)

turtle.exitonclick()

但是，我的撤消技巧可能对每个人都不够严格。