alien_invasion

import sys
from time import sleep  # sleep函数使飞船撞到外星人后让游戏暂停一会
import pygame

from settings import Settings
from game_stats import GameStats
from scoreboard import Scoreboard
from button import Button
from ship import Ship
from bullet import Bullet
from alien import Alien


class AlienInvasion:
    def __init__(self):
        pygame.init()
        self.clock = pygame.time.Clock()
        self.settings = Settings()

        self.screen = pygame.display.set_mode((0, 0), pygame.FULLSCREEN)
        self.settings.screen_width = self.screen.get_rect().width
        self.settings.screen_height = self.screen.get_rect().height
        pygame.display.set_caption('Alien Invasion')

        # 创建存储游戏统计信息的实例，并创建记分牌
        self.stats = GameStats(self)
        self.sb = Scoreboard(self)

        self.ship = Ship(self)
        self.bullets = pygame.sprite.Group()
        self.aliens = pygame.sprite.Group()

        self._create_fleet()

        # 游戏启动后处于活动状态
        self.game_active = False

        # 创建play按钮
        # 这些代码创建一个标签为play的button实例，但没有将他显示到屏幕上
        self.play_button = Button(self, "play")

    def run_game(self):
        while True:
            # 在所有情况下都需要运行_check_events()，即便处于非活动状态也是如此。
            self._check_events()

            if self.game_active:
                self.ship.update()
                self._update_bullet()
                self._update_aliens()

            self._update_screen()
            self.clock.tick(60)

    def _check_events(self):
        for event in pygame.event.get():
            if event.type == pygame.QUIT:
                sys.exit()
            elif event.type == pygame.KEYDOWN:
                self._check_keydown_events(event)
            elif event.type == pygame.KEYUP:
                self._check_keyup_events(event)
            elif event.type == pygame.MOUSEBUTTONDOWN:
                mouse_pos = pygame.mouse.get_pos()
                self._check_play_button(mouse_pos)

    def _check_play_button(self, mouse_pos):
        """在玩家单击paly按钮时开始新游戏"""
        # 使用rect的collidepoint()方法检查鼠标的单机位置是否在play按钮的rect内
        button_clicked = self.play_button.rect.collidepoint(mouse_pos)
        # 仅当玩家单机了play按钮且游戏处于非活动状态是，游戏才会重新开始
        if button_clicked and not self.game_active:
            # 还原游戏的设置
            self.settings.initialize_dynamic_settings()
            self.stats.reset_stasts()
            self.sb.prep_score()
            # 为了确保在开始新游戏时更新等级图像，还需在玩家单击按钮play时调用prep_level()
            self.sb.prep_level()
            # 让玩家知道自己有多少艘飞船
            self.sb.prep_ships()
            self.game_active = True

            # 清空外星人列表和子弹列表
            self.bullets.empty()
            self.aliens.empty()

            # 创建一个新的外星舰队，并将飞船放在屏幕底部的中央
            self._create_fleet()
            self.ship.center_ship()

            # 隐藏光标
            pygame.mouse.set_visible(False)

    def _check_keydown_events(self, event):
        if event.key == pygame.K_RIGHT:
            self.ship.moving_right = True
        elif event.key == pygame.K_LEFT:
            self.ship.moving_left = True
        elif event.key == pygame.K_q:
            sys.exit()
        elif event.key == pygame.K_SPACE:
            self._fire_bullet()

    def _check_keyup_events(self, event):
        if event.key == pygame.K_RIGHT:
            self.ship.moving_right = False
        elif event.key == pygame.K_LEFT:
            self.ship.moving_left = False

    def _create_fleet(self):
        alien = Alien(self)
        alien_width, alien_height = alien.rect.size

        current_x, current_y = alien_width, alien_height
        while current_y < (self.settings.screen_height - 3 * alien_height):
            while current_x < (self.settings.screen_width - 2 * alien_width):
                self._create_alien(current_x, current_y)
                current_x += 2 * alien_width

            current_x = alien_width
            current_y += 2 * alien_height

    def _create_alien(self, x_position, y_position):
        new_alien = Alien(self)
        new_alien.x = x_position
        new_alien.rect.x = x_position
        new_alien.rect.y = y_position
        self.aliens.add(new_alien)

    def _fire_bullet(self):
        new_bullet = Bullet(self)
        self.bullets.add(new_bullet)

    def _update_bullet(self):
        self.bullets.update()

        for bullet in self.bullets.copy():
            if bullet.rect.bottom <= 0:
                self.bullets.remove(bullet)

        self._check_bullet_alien_collisions()

    def _check_bullet_alien_collisions(self):
        collisions = pygame.sprite.groupcollide(
            self.bullets, self.aliens, True, True)

        if collisions:
            # 当有子弹击中外星人时，pygame返回字典collisions
            for alien in collisions.values():
                self.stats.score += self.settings.alien_points * len(alien)
            self.sb.prep_score()
            # 如果字典存在，就根据击落的外星人数量更新分数，在调用check_high_score()
            self.sb.check_high_score()

        if not self.aliens:
            # 删除现有的子弹并创建一个新的外星舰队
            self.bullets.empty()
            self._create_fleet()
            # 在整个外星舰队被全部消灭后调用increase_speed()来加快游戏的节奏
            self.settings.increase_speed()

            # 提高等级
            # 如果整个外星舰队都被击落，就将stats.level得值加1，并调用prep_level()以确保正确地显示了新等级
            self.stats.level += 1
            self.sb.prep_level()

    def _update_aliens(self):
        self._check_fleet_edges()
        self.aliens.update()

        # 检测外星人与飞船之间的碰撞
        if pygame.sprite.spritecollideany(self.ship, self.aliens):
            self._ship_hit()

        # 检查是否有外星人到达了屏幕的下边缘
        # 每当有外星人撞到飞船或抵达屏幕的下边缘时，都将出现一个新的外星舰队
        self._check_alien_bottom()

    def _check_fleet_edges(self):
        for alien in self.aliens.sprites():
            if alien.check_edges():
                self._change_fleet_direction()
                break

    def _change_fleet_direction(self):
        for alien in self.aliens.sprites():
            alien.rect.y += self.settings.fleet_drop_speed
        self.settings.fleet_direction *= -1

    def _check_alien_bottom(self):
        """检查是否有外星人到达了屏幕的下边缘"""
        for alien in self.aliens.sprites():
            if alien.rect.bottom >= self.settings.screen_height:
                # 像飞船被撞到一样进行处理
                self._ship_hit()
                break

    def _ship_hit(self):
        """响应飞船和外星人的碰撞"""
        # 将ships_left 减 1
        # 检查飞船数量是否大于一
        if self.stats.ships_left > 0:
            self.stats.ships_left -= 1
            # 飞船撞到外星人，飞船显示数量减1
            self.sb.prep_ships()

            # 清空外星人列表和子弹列表
            self.bullets.empty()
            self.aliens.empty()

            # 创建一个新的外星舰队，并将飞船放在屏幕底部的中央
            self._create_fleet()
            self.ship.center_ship()

            # 暂停
            sleep(0.5)

        else:
            # 在玩家的飞船用完后将game_active设置为False
            self.game_active = False
            pygame.mouse.set_visible(True)

    def _update_screen(self):
        self.screen.fill(self.settings.bg_color)
        for bullet in self.bullets.sprites():
            bullet.draw_bullet()
        self.ship.blitme()
        self.aliens.draw(self.screen)

        # 显示得分
        self.sb.show_score()

        # 如果游戏处于非活动状态，就绘制play按钮
        if not self.game_active:
            self.play_button.draw_button()

        pygame.display.flip()


if __name__ == "__main__":
    ai = AlienInvasion()
    ai.run_game()

settings

class Settings:
    def __init__(self):
        """初始化游戏的静态设置"""
        # 屏幕设置
        self.screen_width = 1200
        self.screen_height = 800
        self.bg_color = (230, 230, 230)

        # 飞船设置
        self.ship_limit = 3  # 三条命

        # 子弹设置
        self.bullet_width = 3
        self.bullet_height = 15
        self.bullet_color = (60, 60, 60)
        self.bullet_allowed = 3

        # 外星人设置
        self.fleet_drop_speed = 10

        # 以什么速度加快游戏的节奏
        self.speedup_scale = 1.1

        # 外星人分数的提高速度
        self.score_scale = 1.5

        self.initialize_dynamic_settings()

    def initialize_dynamic_settings(self):
        """初始化随游戏进行而变化的设置"""
        self.ship_speed = 2.0
        self.bullet_speed = 3.0
        self.alien_speed = 1.0

        # fleet_direction 为1表示向右，为-1表示向左
        self.fleet_direction = 1

        # 计分设置
        self.alien_points = 50

    def increase_speed(self):
        """提高速度设置的值"""
        self.ship_speed *= self.speedup_scale
        self.bullet_speed *= self.speedup_scale
        self.alien_speed *= self.speedup_scale

        self.alien_points = int(self.alien_points * self.score_scale)

bullet

import pygame
from pygame.sprite import Sprite

class Bullet(Sprite):
    def __init__(self, ai_game):
        super().__init__()
        self.screen = ai_game.screen
        self.settings = ai_game.settings
        self.color = self.settings.bullet_color

        self.rect = pygame.Rect(0, 0, self.settings.bullet_width, self.settings.bullet_height)
        self.rect.midtop = ai_game.ship.rect.midtop

        self.y = float(self.rect.y)

    def update(self):
        self.y -= self.settings.bullet_speed
        self.rect.y = self.y

    def draw_bullet(self):
        pygame.draw.rect(self.screen, self.color, self.rect)

aliens

import pygame
from pygame.sprite import Sprite


class Alien(Sprite):

    def __init__(self, ai_game):
        super().__init__()
        self.screen = ai_game.screen
        self.settings = ai_game.settings

        self.image = pygame.image.load('images/alien.bmp')
        self.rect = self.image.get_rect()

        self.rect.x = self.rect.width
        self.rect.y = self.rect.height

        self.x = float(self.rect.x)

    def check_edges(self):
        screen_rect = self.screen.get_rect()
        return (self.rect.right >= screen_rect.right) or (self.rect.left <= 0)

    def update(self):
        self.x += self.settings.alien_speed * self.settings.fleet_direction
        self.rect.x = self.x

ship

import pygame
from pygame.sprite import Sprite

class Ship(Sprite):
    # 让ship继承sprite，并在 __init__()开头调用super()以完成精灵得初始化工作
    def __init__(self, ai_game):
        """初始化飞船并设置其起始位置"""
        super().__init__()
        self.screen = ai_game.screen
        self.settings = ai_game.settings
        self.screen_rect = ai_game.screen.get_rect()

        self.image = pygame.image.load('images/ship.bmp')
        self.rect = self.image.get_rect()

        self.rect.midbottom = self.screen_rect.midbottom
        self.x = float(self.rect.x)

        self.moving_right = False
        self.moving_left = False

    def update(self):
        if self.moving_right and self.rect.right < self.screen_rect.right:
            self.x += self.settings.ship_speed
        if self.moving_left and self.rect.left > 0:
            self.x -= self.settings.ship_speed

        self.rect.x = self.x

    def blitme(self):
        self.screen.blit(self.image, self.rect)

    def center_ship(self):
        """将飞船放在屏幕底部中央"""
        self.rect.midbottom = self.screen_rect.midbottom
        self.x = float(self.rect.x)  # rect.x用于跟踪飞船确切位置的属性

game_stats

class GameStats:
    """跟踪游戏的统计信息"""

    def __init__(self, ai_game):
        """初始化统计信息"""
        self.settings = ai_game.settings
        self.reset_stasts()

        # 在任何情况下都不会重置最高分
        self.high_score = 0

    def reset_stasts(self):
        """初始化在游戏运行期间可能变化的统计信息"""
        # 然后在_init_()中直接初始化
        self.ships_left = self.settings.ship_limit
        # 每次游戏开始时都重置得分
        self.score = 0
        # 初始等级为1
        self.level = 1

scoreboard

import pygame.font
from pygame.sprite import Group

from ship import Ship

class Scoreboard:
    """显示得分信息的类"""
    def __init__(self, ai_game):
        """初始化显示得分涉及的属性"""
        # 将游戏属性赋给一个属性，因为创建飞船时需要用到它
        self.ai_game = ai_game
        self.screen = ai_game.screen
        self.screen_rect = ai_game.screen.get_rect()
        self.settings = ai_game.settings
        self.stats = ai_game.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)

        # 准备最高分和当前的分的图像
        self.prep_score()  # 将显示的文本转化为图像
        self.prep_high_score()
        self.prep_level()
        self.prep_ships()

    def prep_score(self):
        """将得分渲染为图像"""
        # round()函数让浮点数精确到小数点后某一位，其中的小数位数由第二个实参指定
        rounded_score = round(self.stats.score, -1)
        score_str = f"{rounded_score:,}"  # 将数值stats.score转化为字符串
        # 再将这个字符串传递给创建图像的render()
        self.score_image = self.font.render(score_str, True, self.text_color)
        # 在屏幕右上角显示得分
        self.score_rect = self.score_image.get_rect()
        # 右边缘与屏幕边缘相距20像素
        self.score_rect.right = self.screen_rect.right - 20
        # 让其上边缘与屏幕上边缘相距20像素
        self.score_rect.top = 20

    def show_score(self):
        """在屏幕上显示得分"""
        self.screen.blit(self.score_image, self.score_rect)
        self.screen.blit(self.high_score_image, self.high_score_rect)
        # 在屏幕上显示等级图像
        self.screen.blit(self.level_image, self.level_rect)
        # 在屏幕上绘制每艘飞船
        self.ships.draw(self.screen)

    def prep_high_score(self):
        """将最高分渲染为图像"""
        # 将最高分舍入到最近的10的整数倍，并添加用逗号表示的千位分隔符
        high_score = round(self.stats.high_score, -1)
        high_score_str = f"{high_score:,}"
        # 根据最高分生成一幅图像
        self.high_score_image = self.font.render(high_score_str, True,
                                                 self.text_color, self.settings.bg_color)

        # 将最高分放在屏幕顶部的中央
        self.high_score_rect = self.high_score_image.get_rect()
        # 使其水平居中
        self.high_score_rect.centerx = self.screen_rect.centerx
        # 将其top属性设置为当前得分图像的top属性
        self.high_score_rect.top = self.score_rect.top

    def check_high_score(self):
        """检查是否诞生了新的最高分"""
        if self.stats.score > self.stats.high_score:
            # 如果当前得分更高，就更新high_score的值，并调用prep_high_score()来更新包含最高分的图像
            self.stats.high_score = self.stats.score
            self.prep_high_score()

    def prep_level(self):
        """将等级渲染为图像"""
        # prep_level()方法会根据存储在stats.level中的值创建一副图像
        level_str = str(self.stats.level)
        self.level_image = self.font.render(level_str, True,
                self.text_color, self.settings.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.right
        # 将rect属性设置为得分的right属性
        self.level_rect.top = self.score_rect.bottom + 10
        # 将top属性设置得比得分图像bottom属性大10像素，在得分和等级之间留出一定的空间

    def prep_ships(self):
        """显示还余下多少飞船"""
        self.ships = Group()  # 用来存储飞船实例
        for ship_number in range(self.stats.ships_left):
            ship = Ship(self.ai_game)
            ship.rect.x = 10 + ship_number * ship.rect.width
            # 让飞船编组都位于屏幕左边缘，且没艘飞船得左边距都为10像素
            ship.rect.y = 10
            # y坐标设置为距离屏幕上边缘10像素，让所有飞船都出现在屏幕的左上角
            self.ships.add(ship)
            # 将每艘新飞船都添加到ships编组中

button

import pygame.font  # 让pygame能够将文本渲染到屏幕上

class Button:
    """为游戏创建按钮的类"""

    def __init__(self, ai_game, msg):  # msg是要在按钮中显示的文本
        """初始化按钮的属性"""
        self.screen = ai_game.screen
        self.screen_rect = ai_game.screen.get_rect()

        # 设置按钮的尺寸和其他属性
        self.width, self.height = 200, 50
        self.button_color = (0, 135, 0)  # 将按钮设置为深绿色
        self.text_color = (255, 255, 255)  # 并通过设置text_color让文本为白色
        # 实参none让pygame使用默认字体，而48指定了文本的字号
        self.font = pygame.font.SysFont(None, 48)

        # 创建按钮的rect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)

    def _prep_msg(self, msg):
        """将msg渲染为图像，并使其在按钮上居中"""
        # pygame处理文本的方式是，将要显示的字符串渲染为图像，最后，调用_prep_msg()来处理这样的渲染
        self.msg_image = self.font.render(msg, True, self.text_color,
                                          self.button_color)
        # font.render()方法还接受一个布尔实参，该实参指定是否开启反锯齿功能
        # 余下的两个实参分别是文本颜色和背景色

        # 让文本图像在按钮上居中：根据文本图像创建一个rect，并将其center属性设置为按钮的center属性
        self.msg_image_rect = self.msg_image.get_rect()
        self.msg_image_rect.center = self.rect.center

    def draw_button(self):
        """绘制一个用颜色填充的按钮，在绘制文本"""
        # 调用screen.fill()来绘制表示按钮的矩形，
        # 在调用screen.blit()来向它传递一副图像以及该图像相关联的rect，
        # 从而在屏幕上绘制文本图像
        self.screen.fill(self.button_color, self.rect)
        self.screen.blit(self.msg_image, self.msg_image_rect)