4-多阶段
原理
本章是对第2章的延续。
我们希望为游戏添加多个阶段，比如开始界面、游戏界面、结束界面等。
为此，我们可以使用一个类来管理游戏的不同阶段。
我们创建了GameManager类，并通过self.status属性表示不同的阶段。
intro阶段：显示准备的背景。当用户按下鼠标时，将状态切换为main_gamemain_game阶段：进行游戏，更新游戏画面。
class GameManager: def __init__(self): self.status = "intro" def intro(self): for event in pygame.event.get(): if event.type == pygame.QUIT: pygame.quit() exit() if event.type == pygame.MOUSEBUTTONDOWN: self.status = "main_game" screen.blit(bg_img, (0, 0)) screen.blit(ready_img, (screen_width//2, screen_height//2)) pygame.display.flip() def main_game(self): for event in pygame.event.get(): if event.type == pygame.QUIT: pygame.quit() exit() if event.type == pygame.MOUSEBUTTONDOWN: crosshair.shoot() screen.blit(bg_img, (0, 0)) target_group.update() target_group.draw(screen) crosshair_group.update() crosshair_group.draw(screen) pygame.display.flip() def start_game(self): if self.status == "intro": self.intro() elif self.status == "main_game": self.main_game() game_manager = GameManager() while True: game_manager.start_game() clock.tick(60)
使用GameManager类管理游戏后，我们发现游戏的主循环变得很简单。
案例
完整代码。
添加了准备阶段。
# 使用pygame SPrite实现射击游戏 import pygame import random class Crosshair(pygame.sprite.Sprite): def __init__(self, img_path): super().__init__() self.image = pygame.image.load(img_path) self.rect = self.image.get_rect() self.gun_shot = pygame.mixer.Sound('gunshot.wav') def shoot(self): self.gun_shot.play() pygame.sprite.spritecollide(crosshair, target_group, True) def update(self): self.rect.center = pygame.mouse.get_pos() class Target(pygame.sprite.Sprite): def __init__(self, img_path, x, y): super().__init__() self.image = pygame.image.load(img_path) self.rect = self.image.get_rect() self.rect.center = (x, y) def update(self): pass # init pygame.init() screen_width = 800 screen_height = 600 screen = pygame.display.set_mode((screen_width, screen_height)) pygame.mouse.set_visible(False) clock = pygame.time.Clock() crosshair = Crosshair(r'PNG\HUD\crosshair_blue_small.png') crosshair_group = pygame.sprite.Group() crosshair_group.add(crosshair) target_group = pygame.sprite.Group() for i in range(20): x,y = random.randint(0, screen_width), random.randint(0, screen_height) target = Target(r'PNG\Objects\duck_target_yellow.png', x, y) target_group.add(target) bg_img = pygame.image.load(r'PNG\Stall\bg_wood.png') bg_img = pygame.transform.scale(bg_img, (screen_width, screen_height)) ready_img = pygame.image.load(r'PNG\HUD\text_ready.png') class GameManager: def __init__(self): self.status = "intro" def intro(self): for event in pygame.event.get(): if event.type == pygame.QUIT: pygame.quit() exit() if event.type == pygame.MOUSEBUTTONDOWN: self.status = "main_game" screen.blit(bg_img, (0, 0)) screen.blit(ready_img, (screen_width//2, screen_height//2)) pygame.display.flip() def main_game(self): for event in pygame.event.get(): if event.type == pygame.QUIT: pygame.quit() exit() if event.type == pygame.MOUSEBUTTONDOWN: crosshair.shoot() screen.blit(bg_img, (0, 0)) target_group.update() target_group.draw(screen) crosshair_group.update() crosshair_group.draw(screen) pygame.display.flip() def start_game(self): if self.status == "intro": self.intro() elif self.status == "main_game": self.main_game() game_manager = GameManager() while True: game_manager.start_game() clock.tick(60)
