前言
代码来源《python编程从入门到实践》Eric Matthes 署 袁国忠 译
使用软件：PyCharm Community Editor 2022
目的：记录一下按照书上敲的代码
alien_invasion.py
游戏的一些初始化设置，调用已经封装好的函数方法，一个函数的调用实现一个游戏的部分。
import pygamefrom settings import Settingsfrom ship import Shipimport game_functions as gffrom pygame.sprite import Groupfrom game_stats import GameStatsfrom button import Buttonfrom scoreboard import Scoreboarddef run_game():# 初始化游戏并创建一个屏幕对象pygame.init()ai_settigns = Settings()# 里面是一个元组screen = pygame.display.set_mode((ai_settigns.screen_width, ai_settigns.screen_height))# 窗口尺寸，宽高# screen=pygame.display.set_mode((1200,800))# 窗口标题pygame.display.set_caption("Alien Invasion")# 创建Play按钮play_button = Button(ai_settigns, screen, "Play")# 创建一个用于存储游戏统计信息的实例stats = GameStats(ai_settigns)# 创建储存游戏统计信息的实例，并创建记分牌sb = Scoreboard(ai_settigns, screen, stats)# 设置背景色# bg_color=(230,230,230)# 创建一艘飞船、一个子弹编组和一个外星人编组ship = Ship(ai_settigns, screen)# 创建一个用于存储子弹的编组bullets = Group()# 创建一个外星人# alien=Alien(ai_settigns,screen)aliens = Group()# 创建外星人群gf.create_fleet(ai_settigns, screen, ship, aliens)# 开始游戏的主循环while True:gf.check_events(ai_settigns, screen, stats, sb, play_button, ship, aliens, bullets)if stats.game_active:ship.update()gf.update_bullets(ai_settigns, screen, stats, sb, ship, aliens, bullets)gf.update_aliens(ai_settigns, screen, stats, sb, ship, aliens, bullets)# print(len(bullets))gf.update_screen(ai_settigns, screen, stats, sb, ship, aliens, bullets, play_button)# 监视键盘和鼠标事件# for event in pygame.event.get():# if event.type==pygame.QUIT:# sys.exit()# 每次循环都重绘屏幕# screen.fill(bg_color)# screen.fill(ai_settigns.gb_color)# ship.blitme()# 让最近绘制的屏幕可见# pygame.display.flip()run_game()game_functions.py
游戏主体，具体功能的实现被封装在里面，按下按键、松开按键的响应，界面的更新、子弹的发射、外星人和飞船之间碰撞的检查等等。
import sysimport pygamefrom bullet import Bulletfrom alien import Alienfrom time import sleep# 响应按键def check_keydown_events(event, ai_settings, screen, ship, bullets):if event.key == pygame.K_RIGHT:ship.moving_right = Trueelif event.key == pygame.K_LEFT:ship.moving_left = Trueelif event.key == pygame.K_SPACE:fire_bullet(ai_settings, screen, ship, bullets)# 按下键盘上的q键同样关闭游戏界面(需要是英文状态下)elif event.key == pygame.K_q:sys.exit()# 响应松开def check_keyup_events(event, ship):if event.key == pygame.K_RIGHT:ship.moving_right = Falseelif event.key == pygame.K_LEFT:ship.moving_left = False# 响应按键和鼠标事件def check_events(ai_settings, screen, stats, sb, play_button, ship, aliens, bullets):for event in pygame.event.get():if event.type == pygame.QUIT:sys.exit()elif event.type == pygame.KEYDOWN:# if event.key == pygame.K_RIGHT:# ship.moving_right = True# elif event.key == pygame.K_LEFT:# ship.moving_left = Truecheck_keydown_events(event, ai_settings, screen, ship, bullets)elif event.type == pygame.KEYUP:# if event.key == pygame.K_RIGHT:# ship.moving_right = False# elif event.key == pygame.K_LEFT:# ship.moving_left = Falsecheck_keyup_events(event, ship)elif event.type == pygame.MOUSEBUTTONDOWN:mouse_x, mouse_y = pygame.mouse.get_pos()check_play_button(ai_settings, screen, stats, sb, play_button, ship, aliens, bullets, mouse_x, mouse_y)# 更新屏幕上的图像，并切换到新屏幕def update_screen(ai_settings, screen, stats, sb, ship, aliens, bullets, play_button):# 每次循环时都重绘屏幕screen.fill(ai_settings.bg_color)# 在飞船和外星人后面重绘所有子弹for bullet in bullets.sprites():bullet.draw_bullet()ship.blitme()aliens.draw(screen)# 显示得分sb.show_score()# 如果游戏处于非活动状态，就绘制Play按钮if not stats.game_active:play_button.draw_button()# 让最近绘制的屏幕可见pygame.display.flip()# 更新子弹的位置，并删除已经消失的子弹def update_bullets(ai_settings, screen, stats, sb, ship, aliens, bullets):# 更新子弹的位置bullets.update()# 删除已经消失的子弹for bullet in bullets.copy():if bullet.rect.bottom <= 0:bullets.remove(bullet)# 检查是否有子弹击中了外星人# 如果是这样，就删除相应的子弹和外星人check_bullet_alien_collision(ai_settings, screen, stats, sb, ship, aliens, bullets)# 响应子弹和外星人的碰撞def check_bullet_alien_collision(ai_settings, screen, stats, sb, ship, aliens, bullets):# 删除发生碰撞的子弹和外星人collisions = pygame.sprite.groupcollide(bullets, aliens, True, True)if collisions:for aliens in collisions.values():stats.score += ai_settings.alien_pointssb.prep_score()check_high_score(stats, sb)if len(aliens) == 0:# 删除现有的子弹并新建一群外星人(如果整群外星人都被消灭，就提高一个等级)bullets.empty()ai_settings.increase_speed()# 提高等级stats.level += 1sb.prep_level()create_fleet(ai_settings, screen, ship, aliens)# 如果还没有到达限制，就发射一颗子弹def fire_bullet(ai_settings, screen, ship, bullets):# 创建一颗子弹,并将其加入到编组bullets中if len(bullets) 0:# 将ships_letf减1stats.ships_left -= 1# 更新记分牌sb.prep_ships()# 清空外星人列表和子弹列表aliens.empty()bullets.empty()# 创建一群新的外星人，并将飞船放到屏幕底端中央create_fleet(ai_settings, screen, ship, aliens)ship.center_ship()# 暂停sleep(0.5)else:stats.game_active = Falsepygame.mouse.set_visible(True)# 检查是否有外星人到达了屏幕底端def check_aliens_bottom(ai_settings, screen, stats, sb, ship, aliens, bullets):screen_rect = screen.get_rect()for alien in aliens.sprites():if alien.rect.bottom >= screen_rect.bottom:# 向飞船被撞到一样进行处理ship_hit(ai_settings, screen, stats, sb, ship, aliens, bullets)break# 在玩家单机Play按钮时开始新游戏def check_play_button(ai_settings, screen, stats, sb, play_button, ship, aliens, bullets, mouse_x, mouse_y):button_clicked = play_button.rect.collidepoint(mouse_x, mouse_y)if button_clicked and not stats.game_active:# 重置游戏设置ai_settings.initialize_dynamic_settings()# 隐藏光标pygame.mouse.set_visible(False)# 重置游戏统计信息stats.reset_stats()stats.game_active = True# 重置记分牌图像sb.prep_score()sb.prep_high_score()sb.prep_level()sb.prep_ships()# 清空外星人列表和子弹列表aliens.empty()bullets.empty()# 创建一群新的外星人，并让飞船居中create_fleet(ai_settings, screen, ship, aliens)ship.center_ship()# 检查是否诞生了新的最高部分def check_high_score(stats, sb):if stats.score > stats.high_score:stats.high_score = stats.scoresb.prep_high_score()settings.py
游戏的一些初始化数据的储存，子弹的速度，大小，屏幕的大小等等。
# 储存《外星人入侵》所设置的类class Settings():# 初始化游戏的静态属性def __init__(self):# 屏幕设置self.screen_width = 1200self.screen_height = 800self.bg_color = (230, 230, 230)# 飞船设置# 位置self.ship_speed_factor = 1.5self.ship_limit = 3# 子弹设置(宽高，颜色)self.bullet_speed_factor = 1# 速度self.bullet_width = 3# 宽度self.bullet_height = 15# 高度self.bullet_color = 60, 60, 60# 颜色self.bullets_allowed = 3# 外星人设置self.alien_speed_factor = 1self.fleet_drop_speed = 10# fleet_direction为1表示向右移，为-1表示向左移self.fleet_direction = 1# 以什么样的速度加快游戏节奏self.speedup_scale = 1.1# 外星人点数的提高速度self.score_scale = 1.5self.initialize_dynamic_settings()# 记分self.alien_points = 50# 初始化随游戏进行而变化的设置def initialize_dynamic_settings(self):self.ship_speed_factor = 1.5self.bullet_speed_factor = 3self.alien_speed_factor = 1# fleet_direction为1表示向右；为-1表示向左self.fleet_direction = 1# 提高速度和外星人点数设置def increase_speed(self):self.ship_speed_factor *= self.speedup_scaleself.bullet_speed_factor *= self.speedup_scaleself.alien_speed_factor *= self.speedup_scaleself.alien_points = int(self.alien_points * self.score_scale)print(self.alien_points)ship.py
飞船的初始化信息（在屏幕上面显示的位置）和移动。
import pygamefrom pygame.sprite import Spriteclass Ship(Sprite):# 初始化飞船并设置其初始位置def __init__(self, ai_settings, screen):super(Ship, self).__init__()self.screen = screenself.ai_settings = ai_settings# 加载飞船图像并获取外接矩形self.image = pygame.image.load('images/ship.png')self.rect = self.image.get_rect()self.screen_rect = screen.get_rect()# 将每艘新飞船放在屏幕底部中央self.rect.centerx = self.screen_rect.centerxself.rect.bottom = self.screen_rect.bottom# 在飞船的属性center中存储小数值self.center = float(self.rect.centerx)# 移动标志self.moving_right = Falseself.moving_left = False# 根据移动标志调整飞船的位置def update(self):# 更新飞船的center值，而不是rect# if self.moving_right:# 增加不能越界的条件if self.moving_right and self.rect.right 0:# self.rect.centerx -= 1self.center -= self.ai_settings.ship_speed_factor# 根据self.center更新rect对象self.rect.centerx = self.center# 在指定位置绘制飞船def blitme(self):self.screen.blit(self.image, self.rect)# 让飞船在屏幕上居中def center_ship(self):self.center = self.screen_rect.centerxalien.py
外星人的初始信息（在屏幕上面显示的位置）和移动。
import pygamefrom pygame.sprite import Sprite# 表示单个外星人的类class Alien(Sprite):# 初始化外星人并设置起始位置def __init__(self, ai_settings, screen):super(Alien, self).__init__()self.screen = screenself.ai_settins = ai_settings# 加载外星人图像，并设置其rect属性self.image = pygame.image.load('images/alien.png')self.rect = self.image.get_rect()# 每个外星人最初都在屏幕左上角附近self.rect.x = self.rect.widthself.rect.y = self.rect.height# 存储外星人的准确位置self.x = float(self.rect.x)# 在指定位置绘制外星人def blitme(self):self.screen.blit(self.image, self.rect)# 向右、左移动外星人def update(self):# self.x += self.ai_settins.alien_speed_factorself.x += (self.ai_settins.alien_speed_factor * self.ai_settins.fleet_direction)self.rect.x = self.x# 如果外星人位于屏幕边缘，就返回Truedef check_edges(self):screen_rect = self.screen.get_rect()if self.rect.right >= screen_rect.right:return Trueelif self.rect.left <= 0:return Truebullet.py
子弹的显示和移动。
import pygamefrom pygame.sprite import Sprite# 一个对飞船发射的子弹进行管理的类class Bullet(Sprite):# 在飞船所处的位置创建一个子弹对象def __init__(self, ai_settings, screen, ship):super(Bullet, self).__init__()self.screen = screen# 在(0,0)处创建一个表示子弹的矩形，在设置正确的位置self.rect = pygame.Rect(0, 0, ai_settings.bullet_width, ai_settings.bullet_height)self.rect.centerx = ship.rect.centerxself.rect.top = ship.rect.top# 存储用小数表示的子弹位置self.y = float(self.rect.y)self.color = ai_settings.bullet_colorself.speed_factor = ai_settings.bullet_speed_factor# 向上移动子弹def update(self):# 更新表示子弹位置的小数值self.y -= self.speed_factor# 更新表示子弹的rect的位置self.rect.y = self.y# 在屏幕上绘制子弹def draw_bullet(self):pygame.draw.rect(self.screen, self.color, self.rect)game_stats.py
游戏是否结束，统计游戏运行期间的变化。
# 跟踪游戏的统计信息class GameStats():# 初始化统计信息def __init__(self, ai_settings):self.ai_settings = ai_settingsself.reset_stats()# 游戏刚启动时处于非活动状态self.game_active = False# 在任何情况下都不应重置最高得分self.high_score = 0# 初始化在游戏运行期间可能变化的统计信息def reset_stats(self):self.ships_left = self.ai_settings.ship_limitself.score = 0self.level = 1
button.py
开始按钮
import pygame.fontclass Button():# 初始化按钮的属性def __init__(self, ai_setting, screen, msg):self.screen = screenself.screen_rect = screen.get_rect()# 设置按钮的尺寸和其他属性self.width, self.height = 200, 50self.button_color = (0, 0, 0)self.text_color = (255, 255, 255)self.font = pygame.font.SysFont(None, 48)# 创建按钮的rect的对象，并使其居中self.rect = pygame.Rect(0, 0, self.width, self.height)self.rect.center = self.screen_rect.center# 按钮的标签只需创建一次self.prep_msg(msg)# 将msg渲染为图像，并使其在按钮上居中def prep_msg(self, msg):self.msg_image = self.font.render(msg, True, self.text_color, self.button_color)self.msg_image_rect = self.msg_image.get_rect()self.msg_image_rect.center = self.rect.center# 绘制一个用颜色填充的按钮，再绘制文本def draw_button(self):self.screen.fill(self.button_color, self.rect)self.screen.blit(self.msg_image, self.msg_image_rect)scoreboard.py
当前得分，和最高得分
import pygame.fontfrom pygame.sprite import Groupfrom ship import Ship# 显示得分信息的类class Scoreboard():def __init__(self, ai_setting, screen, stats):self.screen = screenself.screen_rect = screen.get_rect()self.ai_setting = ai_settingself.stats = stats# 显示得分信息时使用的字体设置self.text_color = (30, 30, 30)self.font = pygame.font.SysFont(None, 48)# 准备初始得分图像self.prep_score()self.prep_high_score()self.prep_level()self.prep_ships()# 将得分转换为一幅渲染的图像def prep_score(self):rounded_score = int(round(self.stats.score, -1))score_str = "{:,}".format(rounded_score)self.score_image = self.font.render(score_str, True, self.text_color, self.ai_setting.bg_color)# 将得分放在屏幕右上角self.score_rect = self.score_image.get_rect()self.score_rect.right = self.screen_rect.right - 20;self.score_rect.top = 20# 在屏幕上显示得分和飞船def show_score(self):self.screen.blit(self.score_image, self.score_rect)self.screen.blit(self.high_score_image, self.high_score_rect)self.screen.blit(self.level_image, self.level_rect)# 绘制飞船self.ships.draw(self.screen)# 将最高得分转换为渲染的图像def prep_high_score(self):high_score = int(round(self.stats.high_score, -1))high_score_str = "{:,}".format(high_score)self.high_score_image = self.font.render(high_score_str, True, self.text_color, self.ai_setting.bg_color)# 将最高得分放在屏幕顶部中央self.high_score_rect = self.high_score_image.get_rect()self.high_score_rect.centerx = self.screen_rect.centerxself.high_score_rect.top = self.score_rect.top# 将等级转换为渲染的图像def prep_level(self):self.level_image = self.font.render(str(self.stats.level), True, self.text_color, self.ai_setting.bg_color)# 将等级放在得分下方self.level_rect = self.level_image.get_rect()self.level_rect.right = self.score_rect.rightself.level_rect.top = self.score_rect.bottom + 10# 显示还余下多少艘飞船def prep_ships(self):self.ships = Group()for ship_number in range(self.stats.ships_left):ship = Ship(self.ai_setting, self.screen)ship.rect.x = 10 + ship_number * ship.rect.widthship.rect.y = 10self.ships.add(ship)我们的飞船和下面的飞船相撞或者撞到下面的墙都会输出：“Ship hit!!!”(程序中已经注释)
图片可以自己去找，如果想修改图片可以运用电脑的“画图”工具来实现。
总结
主要是记录一下这个，毕竟敲了这么久了，不过还是要理解。
整个游戏的结构还是是否清晰的，游戏的流程储存在alien_invasion中，为了让程序的可读性更好，把功能封装成对应的函数，把这些函数全部储存到game_functions中，把游戏需要初始化的数据（子弹的大小，颜色，速度等等）全部储存到settings中，ship是对飞船的抽象表示，alien是对外星人的抽象表示，bullet是对子弹的抽象表示，通过button来开始游戏，game_stats来记录整个游戏，用scoreboard统计游戏得分。