20222313实验四 Python综合实践

20222313 2023-05-11 18:59:38

20222313 《Python程序设计》实验四报告
课程：《Python程序设计》
班级： 2223
姓名：冉皓宁
学号：20222313
实验教师：王志强
实验日期：2022年5月6日
必修/选修：公选课

1.关键代码讲解

创建Button类，Alien类，Ship类，Bullet类，Settings类并在alien_invasion中引入包

其中Settings中存放游戏的初始化设置

在alien_invasion中编写游戏运行的run_game函数

（代码过多，请看以下完整代码）

2.完整代码

1.alien_invasion.py

import sys
import pygame

from settings import Settings
from game_stats import GameStats
from ship import Ship
from alien import Alien
from button import Button
from pygame.sprite import Group
import game_functions as gf

def run_game():
    pygame.init()

    ai_settings = Settings()

    screen = pygame.display.set_mode((ai_settings.screen_width,ai_settings.screen_height))
    pygame.display.set_caption("Alien Invasion")

    play_button = Button(ai_settings,screen,"Play")
    ship = Ship(ai_settings,screen)
    bullets = Group()
    aliens = Group()
    alien = Alien(ai_settings,screen)
    stats = GameStats(ai_settings)

    gf.create_fleet(ai_settings,screen,ship,aliens)

    while True:
        gf.check_events(ai_settings,screen,stats,play_button,ship,aliens,bullets)
        if stats.game_active:
            ship.update()
            gf.update_bullets(ai_settings,screen,ship,aliens,bullets)
            gf.update_aliens(ai_settings,stats,screen,ship,aliens,bullets)
        gf.update_screen(ai_settings,screen,stats,ship,aliens,bullets,play_button)

run_game()

2.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()

        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)

        self.rect = pygame.Rect(0,0,self.width,self.height)
        self.rect.center = self.screen_rect.center

        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):
        self.screen.fill(self.button_color,self.rect)
        self.screen.blit(self.msg_image,self.msg_image_rect)

3.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起始位置"""
        super(Alien,self).__init__()
        self.screen = screen
        self.ai_settings = ai_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 blitme(self):
        """在指定位置绘制外星人"""
        self.screen.blit(self.image,self.rect)

    def check_edges(self):
        """如果外星人位于屏幕边缘，就返回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):
        """向左或向右移动外星人"""
        self.x += (self.ai_settings.alien_speed_factor * self.ai_settings.fleet_direction)
        self.rect.x = self.x

4.ship.py

import pygame

class Ship():
    def __init__(self,ai_settings,screen):
        """初始化飞船并设置其初始位置"""
        self.screen=screen
        self.ai_settings=ai_settings

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

        self.rect.centerx=self.screen_rect.centerx
        self.rect.bottom=self.screen_rect.bottom
        self.center=float(self.rect.centerx)
        self.moving_right = False
        self.moving_left = False

    def center_ship(self):
        """让飞船在屏幕上居中"""
        self.center = self.screen_rect.centerx

    def update(self):
        """根据移动标志调整飞船的位置"""
        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

        self.rect.centerx=self.center

    def blitme(self):
        """在指定位置绘制飞船"""
        self.screen.blit(self.image,self.rect)

5.game_functions.py

import sys
import pygame

from bullet import Bullet
from alien import Alien
from time import sleep

def check_aliens_bottom(ai_settings,stats,screen,ship,aliens,bullets):
    """检查是否有外星人到达了屏幕底端"""
    screen_rect = screen.get_rect()
    for alien in aliens.sprites():
        if alien.rect.bottom >= screen_rect.bottom:
            ship_hit(ai_settings,stats,screen,ship,aliens,bullets)
            break

def get_number_rows(ai_settings,ship_height,alien_height):
    """计算屏幕可容纳多少外星人"""
    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 get_number_aliens_x(ai_settings,alien_width):
    """计算每行可以容纳多少个外星人"""
    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 create_alien(ai_settings,screen,aliens,alien_number,row_nmber):
    """创建一个外星人并将其放在当前行"""
    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_nmber
    aliens.add(alien)

def create_fleet(ai_settings,screen,ship,aliens):
    """创建外星人群"""
    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)
    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)

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)

def fire_bullet(ai_settings,screen,ship,bullets):
    """如果还没有到达限制，就发射一颗子弹"""
    if len(bullets) < ai_settings.bullet_allowed:
        new_bullet = Bullet(ai_settings,screen,ship)
        bullets.add(new_bullet)

def check_keyup_events(event, ship):
    """响应松开"""
    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,play_button,ship,aliens,bullets):
    """响应按键和鼠标事件"""
    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,play_button,ship,aliens,bullets,mouse_x,mouse_y)

def check_play_button(ai_settings,screen,stats,play_button,ship,aliens,bullets,mouse_x,mouse_y):
    """玩家单击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:
        pygame.mouse.set_visible(False)
        stats.reset_stats()
        stats.game_active = True
        aliens.empty()
        bullets.empty()
        create_fleet(ai_settings,screen,ship,aliens)
        ship.center_ship()

def update_screen(ai_settings,screen,stats,ship,aliens,bullets,play_button):
    """更新屏幕上的图像，并切换到新屏幕"""
    screen.fill(ai_settings.bg_color)
    for bullet in bullets.sprites():
        bullet.draw_bullet()
    ship.blitme()
    aliens.draw(screen)
    if not stats.game_active:
        play_button.draw_button()

    pygame.display.flip()

def update_bullets(ai_settings,screen,ship,aliens,bullets):
    """更新子弹的位置，并删除已消失的子弹"""
    bullets.update()
    for bullet in bullets.copy():
        if bullet.rect.bottom <= 0:
            bullets.remove(bullet)

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

def check_bullet_alien_collisions(ai_settings,screen,ship,aliens,bullets):
    """响应子弹和外星人的碰撞"""
    collisions = pygame.sprite.groupcollide(bullets,aliens,True,True)

    if len(aliens) == 0:
        bullets.empty()
        create_fleet(ai_settings,screen,ship,aliens)

def check_fleet_edges(ai_settings,aliens):
    """有外星人到达边缘时采取的措施"""
    for alien in aliens.sprites():
        if alien.check_edges():
            change_fleet_direction(ai_settings,aliens)
            break

def change_fleet_direction(ai_settings,aliens):
    """将整群外星人下移，并改变它们的方向"""
    for alien in aliens.sprites():
        alien.rect.y += ai_settings.fleet_drop_speed
    ai_settings.fleet_direction *= -1

def ship_hit(ai_settings,stats,screen,ship,aliens,bullets):
    """响应被外星人撞到的飞船"""
    if stats.ships_left > 0:
        stats.ships_left -= 1
        aliens.empty()
        bullets.empty()
        create_fleet(ai_settings,screen,ship,aliens)
        ship.center_ship()

        sleep(0.5)
    else:
        stats.game_active = False
        pygame.mouse.set_visible(True)

def update_aliens(ai_settings,stats,screen,ship,aliens,bullets):
    """检查是否有外星人位于屏幕边缘，并更新整群外星人的位置"""
    check_fleet_edges(ai_settings,aliens)
    aliens.update()
    if pygame.sprite.spritecollideany(ship,aliens):
        ship_hit(ai_settings,stats,screen,ship,aliens,bullets)
    check_aliens_bottom(ai_settings,stats,screen,ship,aliens,bullets)

6.settings.py

class Settings():
    """存储《外星人入侵》的所有设置的类"""

    def __init__(self):
        """初始化游戏的设置"""
        self.screen_width = 1200
        self.screen_height = 800
        self.bg_color = (230,230,230)
        self.ship_speed_factor = 1
        self.ship_limit = 3

        self.bullet_speed_factor = 2
        self.bullet_width = 3
        self.bullet_height = 15
        self.bullet_color = (60,60,60)
        self.bullet_allowed = 3

        self.alien_speed_factor = 0.5
        self.fleet_drop_speed = 10
        self.fleet_direction = 1

7.bullet.py

import pygame
from pygame.sprite import Sprite

class Bullet(Sprite):
    """一个对飞船发射的子弹进行管理的类"""

    def __init__(self,ai_settings,screen,ship):
        """在飞船所处的位置创建一个子弹对象"""
        super(Bullet,self).__init__()
        self.screen = screen

        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

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

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

    def update(self):
        """向上移动子弹"""
        self.y -= self.speed_factor
        self.rect.y = self.y

    def draw_bullet(self):
        """在屏幕上绘制子弹"""
        pygame.draw.rect(self.screen,self.color,self.rect)