34 lines
1.1 KiB
Plaintext
34 lines
1.1 KiB
Plaintext
import pygame
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from pygame.sprite import Sprite
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class Alien(Sprite):
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"""表示单个外星人的类"""
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def __init__(self,ai_game):
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"""初始化外星人并设置其起始位置"""
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super().__init__()
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self.screen = ai_game.screen
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self.settings = ai_game.settings
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# 加载外星人图像并设置其rect属性
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self.image = pygame.image.load('images/alien.bmp')
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self.rect = self.image.get_rect()
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# 每个外星人最初都在屏幕左上角附近
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self.rect.x = self.rect.width
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self.rect.y = self.rect.height
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# 存储外星人的精确水平位置
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self.x = float(self.rect.x)
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def check_edges(self):
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"""如果外星人位于屏幕边缘，就返回True"""
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screen_rect = self.screen.get_rect()
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if self.rect.right >= screen_rect.right or self.rect.left <= 0:
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return True
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def update(self):
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"""向左或向右移动外星人"""
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self.x += (self.settings.alien_speed *
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self.settings.fleet_direction)
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self.rect.x = self.x |