Question

我正在编写一个基本的蛇游戏，在屏幕上经过一段时间后，我无法找到一种方法来清除尾巴。有人可以帮忙吗？

Answer 1

我试图使该示例简洁明了，但是您可以看到有几件事可以跟踪何时使蛇的片段基于计时器消失。本示例从窗口的一个角开始蛇向另一角移动，每1/4秒移动一次。每次您在屏幕上单击时，都会获得一个身体部位。但是每1.5秒，它就会失去一个身体部位：

from turtle import Screen, Turtle

CURSOR_SIZE = 20

def add_segment(x, y):
    global locked

    screen.onclick(None)  # disable handler inside handler

    if not locked:
        locked = True

        head = segments[0]

        if spares:
            segment = spares.pop()
            segment.setposition(head.position())
            segment.showturtle()
        else:
            segment = head.clone()

        segment.forward(CURSOR_SIZE)
        segments.insert(0, segment)

        locked = False

    screen.update()

    head = segments[0]

    if head.distance(target) > CURSOR_SIZE:
        screen.onclick(add_segment)  # reenable handler

def remove_segment():
    global locked

    if not locked:
        locked = True

        if len(segments) > 1:
            segment = segments.pop()
            segment.hideturtle()
            spares.append(segment)

        locked = False

    screen.update()

    head = segments[0]

    if head.distance(target) > CURSOR_SIZE:
        screen.ontimer(remove_segment, 1500)
    else:
        screen.onclick(None)

def move_snake():
    global locked

    if not locked:
        locked = True

        for segment in segments:
            segment.forward(CURSOR_SIZE)

        locked = False

    screen.update()

    head = segments[0]

    if head.distance(target) > CURSOR_SIZE:
        screen.ontimer(move_snake, 250)
    else:
        screen.onclick(None)

screen = Screen()
screen.tracer(False)

width, height = screen.window_width(), screen.window_height()

start = CURSOR_SIZE - width/2, CURSOR_SIZE - height/2
target = width/2 - CURSOR_SIZE, height/2 - CURSOR_SIZE

snake = Turtle('circle', visible=False)
snake.penup()
snake.goto(start)
snake.setheading(snake.towards(target))
snake.showturtle()

segments = [snake]
spares = []
locked = False

move_snake()
remove_segment()

screen.onclick(add_segment)
screen.mainloop()

其他人可能建议使用非正式的锁定系统，以防止多个事件试图同时操纵蛇。

在屏幕上经过一定时间后清除海龟绘图

1 个答案: