Pong Collision Pygame

Question

我正在为pygame中的一个拍子乒乓球游戏编写代码，在这个游戏中，球将从没有拍子的三面墙上反弹，当它击中拍子的墙壁而不是拍子时，它会让你失去一条生命。我的问题是，我找不到碰撞检测来做到这一点。以下是我到目前为止所做的工作：

import pygame, sys
from pygame.locals import *

pygame.init()

screen_width = 640
screen_height = 480
Display = pygame.display.set_mode((screen_width, screen_height), 0, 32)
pygame.display.set_caption('Lonely Pong')

back = pygame.Surface((screen_width, screen_height))
background = back.convert()
background.fill((255, 255, 255))

paddle = pygame.Surface((80, 20))
_paddle = paddle.convert()
_paddle.fill((128, 0, 0))

ball = pygame.Surface((15, 15))
circle = pygame.draw.circle(ball, (0, 0, 0), (7, 7), 7)
_ball = ball.convert()
_ball.set_colorkey((0, 0, 0))

_paddle_x = (screen_width / 2) - 40
_paddle_y = screen_height - 20
_paddlemove = 0
_ball_x, _ball_y = 8, 8
speed_x, speed_y, speed_circle = 250, 250, 250
Lives = 5

clock = pygame.time.Clock()
font = pygame.font.SysFont("verdana", 20)
paddle_spd = 5

while True:

    for event in pygame.event.get():
        if event.type == QUIT:
            sys.exit()
        if event.type == KEYDOWN:
            if event.key == K_RIGHT:
                _paddlemove = paddle_spd
            elif event.key == K_LEFT:
                _paddlemove = -paddle_spd
        elif event.type == KEYUP:
            if event.key == K_RIGHT:
                _paddlemove = 0
            elif event.key == K_LEFT:
                _paddlemove = 0

    Livespr = font.render(str(Lives), True, (0, 0, 0))
    Display.blit(background, (0, 0))
    Display.blit(_paddle, (_paddle_x, _paddle_y))
    Display.blit(_ball, (_ball_x, _ball_y))
    Display.blit(Livespr, ((screen_width / 2), 5))

    _paddle_x += _paddlemove

    passed = clock.tick(30)
    sec = passed / 1000

    _ball_x += speed_x * sec
    _ball_y += speed_y * sec

    pygame.display.update()

我一直有的另一个问题是，当我启动它时，球根本不出现。有人能给我指个方向吗？

Answer 1

首先，球不会出现，因为你没有填充表面，你正在设置color_key：

_ball.set_colorkey((0, 0, 0))

应该是

_ball.fill((0, 0, 0))

其次，对于碰撞检测，pygame提供了一些功能，如碰撞点和碰撞检测。

https://www.pygame.org/docs/ref/rect.html#pygame.Rect.collidepoint

这意味着你需要曲面的矩形。为此，请执行以下操作：

my_surface.get_rect()

https://www.pygame.org/docs/ref/surface.html#pygame.Surface.get_rect

为了与屏幕的边缘发生碰撞，你总是可以这样做

if _ball_x <= 0 or _ball_y <= 0 or _ball_x >= 640 or _ball_y >= 480:
    # collision detected