python - 关于碰撞检测和更新标签的说明
问题描述
我正在尝试进行桨球比赛，该比赛需要尽可能长时间地让球远离底部弹跳。在这个游戏中，有 5 条生命，当球击中屏幕底部时会耗尽生命，一旦达到 0 生命就会自动重置。然而，球并没有按应有的方式从球拍上反弹，得分的标签也没有按应有的方式更新。我目前如何尝试实现碰撞的代码与球的垂直放置有关，其相关部分如下：
if vertical_direction == "south":
top_y += dy
if top_y >= (self.canvas_height - ball_diameter) - 20:
if self.top_paddle <= top_y and self.top_paddle + 80 >= top_y:
top_y = self.canvas_height - ball_diameter
vertical_direction = "north"
elif top_y >= self.canvas_height - ball_diameter:
lives -= 1
if (lives >= 0):
top_x = 2
top_y = 2
self.canvas.delete("ball")
ball = self.canvas.create_oval(top_x, top_y, top_x + ball_diameter,
top_y + ball_diameter, fill = "blue", tags = "ball")
var.set("Lives: " +lives_Label)
else:
lives= 5
top_x = 2
top_y = 2
self.canvas.delete(ball)
ball = self.canvas.create_oval(top_x, top_y, top_x + ball_diameter,
top_y + ball_diameter, fill = "blue", tags = "ball")
我查看了一些我发现与我的最相似的代码，并尝试实现其检测碰撞的方法，如上所示。我唯一的猜测是我没有注意到一些明显的逻辑不一致，这对于更有经验的编码人员来说是显而易见的，这就是我的两个问题的原因。
作为参考，这是迄今为止的完整代码：
from tkinter import *
import tkinter.font
class BallBounce (Frame):
def __init__(self):
Frame.__init__(self)
self.master.title("Bouncing Ball")
self.grid()
lives = 5
lives_Label = str(lives)
var = StringVar()
font = tkinter.font.Font(family = "Verdana", size = 20)
self._label = Label(self, font = font, textvariable = var)
var.set("Lives: "+lives_Label)
self._label.grid(row = 0, column = 0)
self.canvas_width = 800
self.canvas_height = 400
self.canvas = Canvas(self, width = self.canvas_width, height = self.canvas_height,
bg = "white")
self.canvas.grid(row = 1, column = 0)
frame = Frame(self)
frame.grid(row = 1, column = 0)
top_x = 0
top_y = 0
ball_diameter = 20
self.canvas.create_oval(top_x, top_y, ball_diameter, ball_diameter, fill = "blue", tags = "ball")
horizontal_direction = "east"
vertical_direction = "south"
self.canvas.create_rectangle (self.canvas_width / 2, self.canvas_height - 20, self.canvas_width / 2 + 80,
self.canvas_height, fill = "black", tags = "paddle")
self.top_paddle = self.canvas_width/2
self.canvas.bind("<Left>", lambda event: self.canvas.move("paddle", -5, 0))
self.canvas.bind("<Right>", lambda event: self.canvas.move("paddle", 5, 0))
self.canvas.focus_set()
dx = 2
dy = 2
while True:
if horizontal_direction == "east":
top_x += dx # dx is 2 because the ball moves 2 pixels horizontally every 15 milliseconds
if top_x >= self.canvas_width - ball_diameter: # ball has hit east wall
top_x = self.canvas_width - ball_diameter
horizontal_direction = "west" # change direction
self.canvas.move("ball", dx, 0) # move ball horizontally dx pixels to the right/east
else: # i.e., horizontal_direction is "west"
top_x -= dx
if top_x <= 0: # ball has hit west wall
top_x = 0 # you may need to adjust this a little
horizontal_direction = "east" # change direction
self.canvas.move("ball", -dx, 0) # move ball horizontally dx pixels to the left/west
if vertical_direction == "south":
top_y += dy
if top_y >= (self.canvas_height - ball_diameter) - 20:
if self.top_paddle <= top_y and self.top_paddle + 80 >= top_y:
top_y = self.canvas_height - ball_diameter
vertical_direction = "north"
elif top_y >= self.canvas_height - ball_diameter:
lives -= 1
if (lives >= 0):
top_x = 2
top_y = 2
self.canvas.delete("ball")
ball = self.canvas.create_oval(top_x, top_y, top_x + ball_diameter,
top_y + ball_diameter, fill = "blue", tags = "ball")
var.set("Lives: " +lives_Label)
else:
lives= 5
top_x = 2
top_y = 2
self.canvas.delete(ball)
ball = self.canvas.create_oval(top_x, top_y, top_x + ball_diameter,
top_y + ball_diameter, fill = "blue", tags = "ball")
self.canvas.move("ball", 0, dy)
else:
top_y -= dy
if top_y <= 0:
top_y = 0
vertical_direction = "south"
self.canvas.move("ball", 0, -dy)
self.canvas.after(15)
self.canvas.update()
def main():
BallBounce().mainloop()
main()