### 实现基于 Pygame 的简单射击游戏 #### 屏幕设置与初始化 为了创建一个简单的射击游戏，首先需要导入 `pygame` 并完成基本的游戏环境配置。 ```python import pygame import random # 定义常量 SCREEN_WIDTH = 800 SCREEN_HEIGHT = 600 FPS = 60 # 初始化Pygame并设置屏幕尺寸和标题 pygame.init() screen = pygame.display.set_mode((SCREEN_WIDTH, SCREEN_HEIGHT)) pygame.display.set_caption('Simple Shooter Game') clock = pygame.time.Clock() background_color = (255, 255, 255) ``` #### 英雄机类定义 英雄机由玩家通过鼠标来控制其位置，并能够发射子弹攻击敌方单位。 ```python class HeroPlane(pygame.sprite.Sprite): def __init__(self, image_path, position): super().__init__() self.image = pygame.image.load(image_path).convert_alpha() self.rect = self.image.get_rect(center=position) def update(self, mouse_pos): self.rect.center = mouse_pos ``` #### 敌机及小蜜蜂类定义 敌机和小蜜蜂会自动从屏幕顶部向下移动。当它们到达底部时重新出现在随机的位置继续下落。 ```python class Enemy(pygame.sprite.Sprite): def __init__(self, image_path, speed_min=1, speed_max=4): super().__init__() self.image = pygame.image.load(image_path).convert_alpha() self.rect = self.image.get_rect( center=(random.randint(0, SCREEN_WIDTH), -50)) self.speed = random.uniform(speed_min, speed_max) def update(self): global score self.rect.y += int(self.speed) if self.rect.top >= SCREEN_HEIGHT: self.reset_position() def reset_position(self): self.rect.x = random.randint(0, SCREEN_WIDTH) self.rect.y = -50 self.speed = random.uniform(1, 4) ``` 对于小蜜蜂可以继承自Enemy类并重写特定方法以实现不同的行为模式[^2]。 #### 子弹类定义 子弹用于打击敌人，每次按下空格键都会生成一颗新子弹向上飞行直到离开视野范围外消失。 ```python class Bullet(pygame.sprite.Sprite): def __init__(self, image_path, start_position): super().__init__() self.image = pygame.image.load(image_path).convert_alpha() self.rect = self.image.get_rect(midbottom=start_position) def update(self): self.rect.move_ip((0, -7)) if self.rect.bottom < 0: self.kill() ``` #### 主程序逻辑 最后，在主循环中处理事件、更新状态以及渲染画面。 ```python def main(): hero_plane = HeroPlane('./images/hero.png', (SCREEN_WIDTH//2, SCREEN_HEIGHT-50)) all_sprites_group = pygame.sprite.Group(hero_plane) enemies_group = pygame.sprite.Group() bullets_group = pygame.sprite.Group() for _ in range(5): # 初始生成五个敌人 enemy = Enemy('./images/enemy.png') enemies_group.add(enemy) all_sprites_group.add(enemy) running = True while running: clock.tick(FPS) screen.fill(background_color) for event in pygame.event.get(): if event.type == pygame.QUIT: running = False elif event.type == pygame.MOUSEBUTTONDOWN and event.button == 1: bullet = Bullet('./images/bullet.png', hero_plane.rect.midtop) bullets_group.add(bullet) all_sprites_group.add(bullet) hits = pygame.sprite.groupcollide(enemies_group, bullets_group, True, True) for hit in hits: score += 10 new_enemy = Enemy('./images/enemy.png') enemies_group.add(new_enemy) all_sprites_group.add(new_enemy) all_sprites_group.update() all_sprites_group.draw(screen) pygame.display.flip() if __name__ == '__main__': try: main() finally: pygame.quit() ```