【有书共读05】python编程--从入门到实践13

1、alien.py

import pygame
from pygame.sprite import Sprite

class Alien(Sprite):
    """表示单个外星人的类"""

    def __init__(self, ai_settings, screen):
        """初始化外星人并设置其位置"""
        super(Alien, self).__init__()
        self.screen = screen
        self.ai_settings = ai_settings

        # 加载外星人图像，设置其rect属性
        self.image = pygame.image.load('images/alien.bmp')
        self.rect = self.image.get_rect()

        # 每个外星人的位置都是屏幕左上角.
        self.rect.x = self.rect.width
        self.rect.y = self.rect.height

        # 存储外星人的准确位置
        self.x = float(self.rect.x)

    def check_edges(self):
        """如果外星人在屏幕边缘，返回True."""
        screen_rect = self.screen.get_rect()
        if self.rect.right >= screen_rect.right:
            return True
        elif self.rect.left <= 0:
            return True

    def update(self):
        """外星人左右移动."""
        self.x += (self.ai_settings.alien_speed_factor *
                        self.ai_settings.fleet_direction)
        self.rect.x = self.x

    def blitme(self):
        """在指定位置绘制外星人的图形."""
        self.screen.blit(self.image, self.rect)

2、alien_invasion.py

import pygame
from pygame.sprite import Group

from settings import Settings
from game_stats import GameStats
from scoreboard import Scoreboard
from button import Button
from ship import Ship
import game_functions as gf

def run_game():
    # 初始化pygame、设置和屏幕对象.
    pygame.init()
    ai_settings = Settings()
    screen = pygame.display.set_mode(
        (ai_settings.screen_width, ai_settings.screen_height))
    pygame.display.set_caption("Alien Invasion")

    # 制作Play按钮.
    play_button = Button(ai_settings, screen, "Play")

    # 创建一个实例来存储游戏统计信息，以及一个记分牌.
    stats = GameStats(ai_settings)
    sb = Scoreboard(ai_settings, screen, stats)

    # 设置背景颜色.
    bg_color = (230, 230, 230)

    # 制作一个飞船、一组子弹、一组外星人.
    ship = Ship(ai_settings, screen)
    bullets = Group()
    aliens = Group()

    # 创建一个外星人舰队.
    gf.create_fleet(ai_settings, screen, ship, aliens)

    # 开始游戏主循环
    while True:
        gf.check_events(ai_settings, screen, stats, sb, play_button, ship,
            aliens, bullets)

        if stats.game_active:
            ship.update()
            gf.update_bullets(ai_settings, screen, stats, sb, ship, aliens,
                bullets)
            gf.update_aliens(ai_settings, screen, stats, sb, ship, aliens,
                bullets)

        gf.update_screen(ai_settings, screen, stats, sb, ship, aliens,
            bullets, play_button)

run_game()

3、bullet.py

import pygame
from pygame.sprite import Sprite

class Bullet(Sprite):
    """管理从船上发射的子弹的类."""

    def __init__(self, ai_settings, screen, ship):
        """在飞船的当前位置创建一个bullet类."""
        super(Bullet, self).__init__()
        self.screen = screen

        # 在（0，0）设置一个表示子弹的矩阵，并设置正确的位置.
        self.rect = pygame.Rect(0, 0, ai_settings.bullet_width,
            ai_settings.bullet_height)
        self.rect.centerx = ship.rect.centerx
        self.rect.top = ship.rect.top

        # 存储一个用小数表示的子弹位置.
        self.y = float(self.rect.y)

        self.color = ai_settings.bullet_color
        self.speed_factor = ai_settings.bullet_speed_factor

    def update(self):
        """子弹向上移动."""
        # 更新用小数表示的子弹位置.
        self.y -= self.speed_factor
        # 更新矩阵位置.
        self.rect.y = self.y

    def draw_bullet(self):
        """将子弹绘制到屏幕上."""
        pygame.draw.rect(self.screen, self.color, self.rect)

4、 button.py

import pygame.font

class Button():

    def __init__(self, ai_settings, screen, msg):
        """初始化按钮的属性."""
        self.screen = screen
        self.screen_rect = screen.get_rect()

        # 设置按钮的大小和其他属性.
        self.width, self.height = 200, 50
        self.button_color = (0, 255, 0)
        self.text_color = (255, 255, 255)
        self.font = pygame.font.SysFont(None, 48)

        # 创建button的rect属性，并使它居中.
        self.rect = pygame.Rect(0, 0, self.width, self.height)
        self.rect.center = self.screen_rect.center

        # 按钮标签只需要准备一次
        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"""
        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

    def draw_button(self):
        # 绘制一个用颜色填充的按钮，在绘制文本.
        self.screen.fill(self.button_color, self.rect)
        self.screen.blit(self.msg_image, self.msg_image_rect)

5、 game_functions.py

import sys
from time import sleep

import pygame

from bullet import Bullet
from alien import Alien

def check_keydown_events(event, ai_settings, screen, ship, bullets):
    """响应按键."""
    if event.key == pygame.K_RIGHT:
        ship.moving_right = True
    elif event.key == pygame.K_LEFT:
        ship.moving_left = True
    elif event.key == pygame.K_SPACE:
        fire_bullet(ai_settings, screen, ship, bullets)
    elif event.key == pygame.K_q:
        sys.exit()

def check_keyup_events(event, ship):
    """响应按键释放."""
    if event.key == pygame.K_RIGHT:
        ship.moving_right = False
    elif event.key == pygame.K_LEFT:
        ship.moving_left = False

def check_events(ai_settings, screen, stats, sb, play_button, ship, aliens,
        bullets):
    """响应按键和鼠标移动."""
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            sys.exit()
        elif event.type == pygame.KEYDOWN:
            check_keydown_events(event, ai_settings, screen, ship, bullets)
        elif event.type == pygame.KEYUP:
            check_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)

def check_play_button(ai_settings, screen, stats, sb, play_button, ship,
        aliens, bullets, mouse_x, mouse_y):
    """当玩家点击Play按钮时，开始新游戏."""
    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()

        # 隐藏游戏光标
        pygame.mouse.set_visible(False)

        # 重置游戏数据.
        stats.reset_stats()
        stats.game_active = True

        # 重绘得分板.
        sb.prep_score()
        sb.prep_high_score()
        sb.prep_level()
        sb.prep_ships()

        #清空子弹和外星人.
        aliens.empty()
        bullets.empty()

        # 创建一个新飞船并将其设置在中间.
        create_fleet(ai_settings, screen, ship, aliens)
        ship.center_ship()

def fire_bullet(ai_settings, screen, ship, bullets):
    """没有限制时，发射子弹."""
    # 创建一个新子弹，并将其加入bullet group中.
    if len(bullets) < ai_settings.bullets_allowed:
        new_bullet = Bullet(ai_settings, screen, ship)
        bullets.add(new_bullet)

def update_screen(ai_settings, screen, stats, sb, ship, aliens, bullets,
        play_button):
    """更新图形，并将其投影到屏幕上."""
    # 每次循环，重绘屏幕.
    screen.fill(ai_settings.bg_color)

    # 重绘所有的bullet、ship和aliens.
    for bullet in bullets.sprites():
        bullet.draw_bullet()
    ship.blitme()
    aliens.draw(screen)

    # 绘制得分信息.
    sb.show_score()

    # 游戏结束重绘Play按钮.
    if not stats.game_active:
        play_button.draw_button()

    # 将重绘图案投影到屏幕上.
    pygame.display.flip()

def update_bullets(ai_settings, screen, stats, sb, ship, aliens, bullets):
    """更新子弹位置，并将旧的子弹移出屏幕."""
    # 更新子弹位置.
    bullets.update()

    # 删除已经在屏幕中消失的子弹.
    for bullet in bullets.copy():
        if bullet.rect.bottom <= 0:
            bullets.remove(bullet)

    check_bullet_alien_collisions(ai_settings, screen, stats, sb, ship,
        aliens, bullets)

def check_high_score(stats, sb):
    """点击此处，查看最高分."""
    if stats.score > stats.high_score:
        stats.high_score = stats.score
        sb.prep_high_score()

def check_bullet_alien_collisions(ai_settings, screen, stats, sb, ship,
        aliens, bullets):
    """响***和外星人相撞."""
    # 移除所有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_points * len(aliens)
            sb.prep_score()
        check_high_score(stats, sb)

    if len(aliens) == 0:
        # 如果整个舰队都被消灭，开始新的等级.
        bullets.empty()
        ai_settings.increase_speed()

        # 提升等级.
        stats.level += 1
        sb.prep_level()

        create_fleet(ai_settings, screen, ship, aliens)

def check_fleet_edges(ai_settings, aliens):
    """响应外星人碰到边界."""
    for alien in aliens.sprites():
        if alien.check_edges():
            change_fleet_direction(ai_settings, aliens)
            break

def change_fleet_direction(ai_settings, aliens):
    """使整个舰队下降，并改变其方向."""
    for alien in aliens.sprites():
        alien.rect.y += ai_settings.fleet_drop_speed
    ai_settings.fleet_direction *= -1

def ship_hit(ai_settings, screen, stats, sb, ship, aliens, bullets):
    """响应飞船被外星人击中."""
    if stats.ships_left > 0:
        # 衰减 ships_left.
        stats.ships_left -= 1

        # 更新得分板.
        sb.prep_ships()

    else:
        stats.game_active = False
        pygame.mouse.set_visible(True)

    # 清空外星人和子弹.
    aliens.empty()
    bullets.empty()

    # 创建一个新的舰队和一个新的飞船.
    create_fleet(ai_settings, screen, ship, aliens)
    ship.center_ship()

    # 暂停.
    sleep(0.5)

def check_aliens_bottom(ai_settings, screen, stats, sb, ship, aliens,
        bullets):
    """检查是否有外星人叨叨屏幕底部."""
    screen_rect = screen.get_rect()
    for alien in aliens.sprites():
        if alien.rect.bottom >= screen_rect.bottom:
            # 认为这种情况和飞船被攻击了相同.
            ship_hit(ai_settings, screen, stats, sb, ship, aliens, bullets)
            break

def update_aliens(ai_settings, screen, stats, sb, ship, aliens, bullets):
    """
    检查舰队是否在边缘,
      更新舰队中所有外星人的位置.
    """
    check_fleet_edges(ai_settings, aliens)
    aliens.update()

    # 寻找飞船和外星人相撞.
    if pygame.sprite.spritecollideany(ship, aliens):
        ship_hit(ai_settings, screen, stats, sb, ship, aliens, bullets)

    # 寻找飞船撞在屏幕底部.
    check_aliens_bottom(ai_settings, screen, stats, sb, ship, aliens, bullets)

def get_number_aliens_x(ai_settings, alien_width):
    """确定一行外星人的数量."""
    available_space_x = ai_settings.screen_width - 2 * alien_width
    number_aliens_x = int(available_space_x / (2 * alien_width))
    return number_aliens_x

def get_number_rows(ai_settings, ship_height, alien_height):
    """确定屏幕中外星人的行数."""
    available_space_y = (ai_settings.screen_height -
                            (3 * alien_height) - ship_height)
    number_rows = int(available_space_y / (2 * alien_height))
    return number_rows

def create_alien(ai_settings, screen, aliens, alien_number, row_number):
    """创建一个外星人，把它放入行中."""
    alien = Alien(ai_settings, screen)
    alien_width = alien.rect.width
    alien.x = alien_width + 2 * alien_width * alien_number
    alien.rect.x = alien.x
    alien.rect.y = alien.rect.height + 2 * alien.rect.height * row_number
    aliens.add(alien)

def create_fleet(ai_settings, screen, ship, aliens):
    """创建一个满的外星人舰队"""
    # 创建一个外星人, 并得出一行外星人的数量.
    alien = Alien(ai_settings, screen)
    number_aliens_x = get_number_aliens_x(ai_settings, alien.rect.width)
    number_rows = get_number_rows(ai_settings, ship.rect.height,
        alien.rect.height)

    # 创建按外星人舰队.
    for row_number in range(number_rows):
        for alien_number in range(number_aliens_x):
            create_alien(ai_settings, screen, aliens, alien_number,
                row_number)

6、 game_stats.py

class GameStats():
    """Track statistics for Alien Invasion."""

    def __init__(self, ai_settings):
        """初始化数据."""
        self.ai_settings = ai_settings
        self.reset_stats()

        # 开始游戏.
        self.game_active = False

        # 最高分不会被重设.
        self.high_score = 0

    def reset_stats(self):
        """在游戏中可能重设的初始化数据."""
        self.ships_left = self.ai_settings.ship_limit
        self.score = 0
        self.level = 1

7、 scoreboard.py

import pygame.font
from pygame.sprite import Group

from ship import Ship

class Scoreboard():
    """显示分数的类."""

    def __init__(self, ai_settings, screen, stats):
        """初始化scoreboard属性."""
        self.screen = screen
        self.screen_rect = screen.get_rect()
        self.ai_settings = ai_settings
        self.stats = stats

        # 得分信息的字体设置.
        self.text_color = (30, 30, 30)
        self.font = pygame.font.SysFont(None, 48)

        # 图片准备.
        self.prep_score()
        self.prep_high_score()
        self.prep_level()
        self.prep_ships()

    def prep_score(self):
        """将得分信息显示在已选图片上."""
        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_settings.bg_color)

        # 将的饭信息显示在屏幕右上方.
        self.score_rect = self.score_image.get_rect()
        self.score_rect.right = self.screen_rect.right - 20
        self.score_rect.top = 20

    def prep_high_score(self):
        """显示最高分."""
        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_settings.bg_color)

        # 将最高分放在正上方.
        self.high_score_rect = self.high_score_image.get_rect()
        self.high_score_rect.centerx = self.screen_rect.centerx
        self.high_score_rect.top = self.score_rect.top

    def prep_level(self):
        """将等级信息显示在图片上."""
        self.level_image = self.font.render(str(self.stats.level), True,
                self.text_color, self.ai_settings.bg_color)

        # 将等级信息显示在得分下方.
        self.level_rect = self.level_image.get_rect()
        self.level_rect.right = self.score_rect.right
        self.level_rect.top = self.score_rect.bottom + 10

    def prep_ships(self):
        """显示飞船剩余数量."""
        self.ships = Group()
        for ship_number in range(self.stats.ships_left):
            ship = Ship(self.ai_settings, self.screen)
            ship.rect.x = 10 + ship_number * ship.rect.width
            ship.rect.y = 10
            self.ships.add(ship)

    def show_score(self):
        """在屏幕上绘制得分."""
        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)

8、 settings.py

class Settings():
    """存储外星人入侵的设置信息"""

    def __init__(self):
        """初始化游戏的数据设置."""
        # 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

        # 子弹设置.
        self.bullet_width = 3
        self.bullet_height = 15
        self.bullet_color = 60, 60, 60
        self.bullets_allowed = 3

        # 外星人设置.
        self.fleet_drop_speed = 10

        # 游戏速度设置.
        self.speedup_scale = 1.1
        # 外星人增加速率.
        self.score_scale = 1.5

        self.initialize_dynamic_settings()

    def initialize_dynamic_settings(self):
        """游戏中初始化设置."""
        self.ship_speed_factor = 1.5
        self.bullet_speed_factor = 3
        self.alien_speed_factor = 1

        # S得分.
        self.alien_points = 50

        # 舰队方向，1代表左面，-1代表右面
        self.fleet_direction = 1

    def increase_speed(self):
        """增加速度设置和 击落外星人分值."""
        self.ship_speed_factor *= self.speedup_scale
        self.bullet_speed_factor *= self.speedup_scale
        self.alien_speed_factor *= self.speedup_scale

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

9、 ship.py

import pygame
from pygame.sprite import Sprite

class Ship(Sprite):

    def __init__(self, ai_settings, screen):
        """初始化飞船, 设置初始位置"""
        super(Ship, self).__init__()
        self.screen = screen
        self.ai_settings = ai_settings

        # 加载飞船图片，获取rect.
        self.image = pygame.image.load('images/ship.bmp')
        self.rect = self.image.get_rect()
        self.screen_rect = screen.get_rect()

        # 开始时飞船位置，位置在底部***.
        self.rect.centerx = self.screen_rect.centerx
        self.rect.bottom = self.screen_rect.bottom

        # 用小数存储飞船的位置.
        self.center = float(self.rect.centerx)

        # 是否移动的标识.
        self.moving_right = False
        self.moving_left = False

    def center_ship(self):
        """将飞船放置在***."""
        self.center = self.screen_rect.centerx

    def update(self):
        """以移动标志为依据，对飞船进行移动."""
        # 更新center的值.
        if self.moving_right and self.rect.right < self.screen_rect.right:
            self.center += self.ai_settings.ship_speed_factor
        if self.moving_left and self.rect.left > 0:
            self.center -= self.ai_settings.ship_speed_factor

        # 用self.center更新rect值.
        self.rect.centerx = self.center

    def blitme(self):
        """绘制飞船."""
        self.screen.blit(self.image, self.rect)

10、 images（文件夹）

（1）alien.bmp

（2）ship.bmp

11、 运行方式

运行alien_invasion.py即可