弹跳球游戏tkinter帆布

Question

我用python写了一个游戏，目标是将球从平台上弹开。 一切运行良好，但平台的运动并不那么顺利。你能帮我让平台移动更顺畅吗？如果代码不是太清楚，对不起，但我是python的新手

import tkinter as tk
import random
root = tk.Tk()
width = 900
height = 500
canvas = tk.Canvas(root, bg='white', width=width, height=height)
canvas.pack()
x = random.randrange(700)
ball = canvas.create_oval(x+10, 10, x+50, 50, fill='green')
platform_y = height - 20
platform = canvas.create_rectangle(width//2-50, platform_y, width//2+50, platform_y+10, fill='black')
xspeed = 2
yspeed = 2
skore = 0
body = 0
def move_ball():
global xspeed
global yspeed
x1, y1, x2, y2 = canvas.coords(ball)
if x1 <= 0 or x2 >= width:
xspeed = -xspeed
if y1 <= 0:
yspeed = 10
elif y2 == platform_y: 
cx = (x1 + x2) // 2
px1, _, px2, _ = canvas.coords(platform)
if px1 <= cx <= px2:
yspeed = -10
else:
canvas.create_text(width//2, height//2, text='Game Over', font=('Arial Bold', 32), fill='red')
return
canvas.move(ball, xspeed, yspeed)
canvas.after(20, move_ball)
def board_right(event):
x1, y1, x2, y2 = canvas.coords(platform) 
if x2 < width:
dx = min(width-x2, 10)
canvas.move(platform, dx, 0)
def board_left(event):
x1, y1, x2, y2 = canvas.coords(platform)
if x1 > 0:
dx = min(x1, 10)
canvas.move(platform, -dx, 0)
canvas.bind_all('<Right>', board_right)
canvas.bind_all('<Left>', board_left)
move_ball()
root.mainloop()

Answer 1

问题是平台的速度取决于键盘的自动重复速度。

不要为每个<Right>或<Left>事件移动一次，而是使用按键启动平台沿所需方向移动，并释放键以停止平台移动。然后，使用after向给定方向重复移动平台。

例：

after_id = None
def platform_move(direction):
"""
direction should be -1 to move left, +1 to move right,
or 0 to stop moving
"""
global after_id
speed = 10
if direction == 0:
canvas.after_cancel(after_id)
after_id = None
else:
canvas.move(platform, direction*speed, 0)
after_id = canvas.after(5, platform_move, direction)
canvas.bind_all("<KeyPress-Right>", lambda event: platform_move(1))
canvas.bind_all("<KeyRelease-Right>", lambda event: platform_move(0))
canvas.bind_all("<KeyPress-Left>", lambda event: platform_move(-1))
canvas.bind_all("<KeyRelease-Left>", lambda event: platform_move(0))

上面的代码不处理您可能同时按下两个键的情况，但这可以通过一些额外的逻辑来处理。重点是展示如何使用这些键来启动和停止动画。