Python开发的飞机打外星人小游戏

跟着《Python从入门到实践》这本书学习的Python，这本书最后的实践部分第一个就是实现一个飞机打外星人的小游戏，跟着书的步骤一步步做最终实现了，并扩展了飞机可以上下移动的功能。

 

游戏有9个py文件，分别是Alien_invasion.py游戏主程序，settings.py游戏设定，alien.py外星人，ship.py飞船，bullet.py子弹，game_status.py游戏启动与否状态，game_function游戏的函数，scoreborad游戏计数板，button.py游戏窗口的按钮。

下面简单说一下各个文件的作用。

 

首先是游戏的主程序Alien_invasion.py，主要是new一个游戏设定setting，new一个飞船，new存储子弹list，new存储外星人list，new计数板，设定初始游戏状态等游戏的初始化工作。

import sys
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
from alien import Alien
import game_function as gf

def run_game():
    #初始化游戏+创建一个屏幕
    pygame.init()
    ai_settings=Settings()
    screen=pygame.display.set_mode((ai_settings.screen_width,ai_settings.screen_height))
    pygame.display.set_caption("Alien Invasion")
    stats=GameStats(ai_settings)
    sb=Scoreboard(ai_settings,screen,stats)

    #Play按钮
    play_button=Button(ai_settings,screen,"Play")
    #创建一艘飞船
    ship=Ship(ai_settings,screen)
    #创建用于存储子弹的编组
    bullets=Group()
    #创建一个外星人编组
    aliens=Group()
    gf.creat_fleet(ai_settings,screen,ship,aliens)
  
    #游戏主循环
    while True:
        gf.check_events(ai_settings, screen, stats,sb, play_button, ship,aliens,bullets)    #监视键盘和鼠标事件
        if stats.game_active:
            ship.update()
            gf.update_bullets(ai_settings,stats,sb,screen,ship,aliens,bullets)
            gf.update_aliens(ai_settings,stats,screen,ship,aliens,bullets)
        gf.update_screen(ai_settings, screen,sb,stats,ship,aliens, bullets,play_button)  #更新屏幕


run_game()

 

settings.py

class Settings():
    #存储《外星人入侵》游戏的设置

    def __init__(self):
        #屏幕及飞船
        self.screen_width=1200
        self.screen_height=700
        self.bg_color=(230,230,230)
        self.ship_speed=3
        self.ship_lives=2
        #子弹
        self.bullet_width=5
        self.bullet_height=10
        self.bullet_speed=3
        self.bullet_color=60,60,60
        self.bullets_total=5
        #敌人
        self.alien_speed=0.5
        self.fleet_drop_speed=50    #敌人撞壁之后向下移动速度
        self.fleet_direction=1      #取1/-1为向右/向左
        self.alien_points=10

 

alien.py

import pygame
from pygame.sprite import Sprite

class Alien(Sprite):
    def __init__(self,ai_settings,screen):
        super(Alien,self).__init__()
        self.screen=screen
        self.ai_settings=ai_settings

        self.image=pygame.image.load('images/alien.bmp')
        self.image=pygame.transform.scale(self.image,(50,50))   #缩放图像
        self.rect=self.image.get_rect()

        #把飞船初始位置设为左上角
        self.rect.x=self.rect.width
        self.rect.y=self.rect.height

        self.x,self.y=0.0,0.0


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

    def check_edges(self):
        screen_rect=self.screen.get_rect()
        if self.rect.right>=screen_rect.right:
            return True
        elif self.rect.right<=0:
            return True
        else:
            return False

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

 

ship.py

#飞船类：管理飞船的行为
import pygame

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

        #self.rect取得飞船矩形     self.screen_rect取得屏幕矩形
        self.image=pygame.image.load("images/ship.bmp")
        self.image=pygame.transform.scale(self.image,(50,50))   #缩放图像
        self.rect=self.image.get_rect()
        self.screen_rect=screen.get_rect()

        '''
        可设置相应 rect 对象的属性center,centerx,centery 
        要让游戏元素与屏幕边缘对齐,可使用属性 top,bottom,left,right ；
        要调整游戏元素的水平或垂直位置，可使用属性 x,y ，它们分别是相应矩形左上角的 x 和 y 坐标。
        '''
        #将飞船放在屏幕最下方中央
        self.rect.centerx=self.screen_rect.centerx
        self.rect.bottom=self.screen_rect.bottom

        #移动标记
        self.moving_right=False
        self.moving_left=False
        self.moving_up=False
        self.moving_down=False

        #移动速度x/y
        self.center=float(self.rect.centerx)
        self.recty=float(self.rect.bottom)

    def update(self):
        #根据移动标记调整飞船位置（横轴）
        if self.moving_right and self.center<self.ai_seettings.screen_width:
            self.center+=self.ai_seettings.ship_speed
        if self.moving_left and self.center>0:
            self.center-=self.ai_seettings.ship_speed
        self.rect.centerx=int(self.center)
        #根据移动标记调整飞船位置（纵轴）
        if self.moving_up and self.recty>0:
            self.recty-=self.ai_seettings.ship_speed
        if self.moving_down and self.recty<self.ai_seettings.screen_height:
            self.recty+=self.ai_seettings.ship_speed
        self.rect.centery=int(self.recty)

    def blitme(self):
        #根据self.rect的指定位置将飞船绘制到屏幕上
        self.screen.blit(self.image,self.rect)

    def center_ship(self):
        self.center=float(self.screen_rect.centerx)
        self.recty=float(self.screen_rect.bottom)

 

bullet.py

import pygame

from pygame.sprite import Sprite

#子弹类：对飞船子弹进行管理，继承自Sprite
class Bullet(Sprite):
    #__init__在飞船位置创建一颗子弹
    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，再设置正确的位置
        self.rect=pygame.Rect(0, 0, ai_settings.bullet_width,ai_settings.bullet_height)
        #x轴设为飞船x轴
        self.rect.centerx = ship.rect.centerx   
        self.rect.top = ship.rect.top   #
  
        #记录self.y值用于以后改变，self.x不会变不用记录
        self.y=float(self.rect.y)

        #子弹颜色和速度
        self.color=ai_settings.bullet_color
        self.bullet_speed=ai_settings.bullet_speed

    #update将子弹向上移动
    def update(self):
        self.y-=self.bullet_speed
        self.rect.y=int(self.y)

    def draw_bullet(self):
        #用self.color的颜色填充self.screen的self.rect的矩形部分
        pygame.draw.rect(self.screen,self.color,self.rect)

 

game_status.py

class GameStats():

    def __init__(self,ai_settings):
        self.ai_settings=ai_settings
        self.reset_stats()

        self.game_active=False

    def reset_stats(self):
        self.ship_lives=self.ai_settings.ship_lives
        self.score=0

 

game_function

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

#响应键盘按下事件
def check_keydown_events(event,ai_settings,screen,ship,bullets):
    if event.key==pygame.K_RIGHT:
        ship.moving_right=True
    if event.key==pygame.K_LEFT:
        ship.moving_left=True
    if event.key==pygame.K_UP:
        ship.moving_up=True
    if event.key==pygame.K_DOWN:
        ship.moving_down=True
    if event.key==pygame.K_SPACE:
        fire_bullet(ai_settings,screen,ship,bullets)
    if event.key==pygame.K_q:
        sys.exit()

def fire_bullet(ai_settings,screen,ship,bullets):
    #监测到按下空格键：创建一颗子弹
    if len(bullets)<ai_settings.bullets_total:
        new_bullet=Bullet(ai_settings,screen,ship)
        bullets.add(new_bullet)

#响应键盘回弹事件
def check_keyup_events(event,ship):
    if event.key==pygame.K_RIGHT:
        ship.moving_right=False
    if event.key==pygame.K_LEFT:
        ship.moving_left=False
    if event.key==pygame.K_UP:
        ship.moving_up=False
    if event.key==pygame.K_LEFT:
        ship.moving_down=False

#监测并响应键盘鼠标事件
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.MOUSEBUTTONDOWN:
            mouse_x,mouse_y=pygame.mouse.get_pos()
            check_play_buttons(ai_settings,screen,stats,sb,play_button,mouse_x,mouse_y,ship,aliens,bullets)
        elif event.type==pygame.KEYDOWN:
            check_keydown_events(event,ai_settings,screen,ship,bullets)
        elif event.type==pygame.KEYUP:
            check_keyup_events(event,ship)

def check_play_buttons(ai_settings,screen,stats,sb,play_button,mouse_x,mouse_y,ship,aliens,bullets):
    if not stats.game_active and play_button.rect.collidepoint(mouse_x, mouse_y):
        pygame.mouse.set_visible(False)

        stats.reset_stats()
        stats.game_active = True

        aliens.empty()
        bullets.empty()

        creat_fleet(ai_settings,screen,ship,aliens)
        ship.center_ship()

        sb.prep_score()

#功能：更新屏幕图像，绘制新的图像
def update_screen(ai_settings, screen,stats,ship,aliens, bullets,play_button):
    #每次循环都重绘屏幕
    screen.fill(ai_setting.bg_color)
    #更新子弹group内子弹位置
    for bullet in bullets.sprites():
        bullet.draw_bullet()
    ship.blitme()
    aliens.draw(screen)
    # 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
def update_bullets(ai_settings,stats,sb,screen,ship,aliens,bullets):
    bullets.update()
    for bullet in bullets.copy():
        if bullet.rect.bottom<=0:
            bullets.remove(bullet)
    #print(len(bullets))
    #内置函数：一行就双重遍历子弹和敌人，矩形重叠就消失
    collisions=pygame.sprite.groupcollide(bullets,aliens,True,True)
    #更新分数
    if collisions:
        for aliens in collisions.values():
            stats.score+=ai_settings.alien_points*len(aliens)
            sb.prep_score()
    #检测现有敌人是否为0了
    if len(aliens)==0:
        bullets.empty()
        creat_fleet(ai_settings,screen,ship,aliens)

#创建外星人舰队：
def creat_fleet(ai_settings,screen,ship,aliens):
    #创建一个外星人，并计算每行可容纳多少个外星人
    alien=Alien(ai_settings,screen)
    number_aliens_x=calc_aliens_number(ai_settings,alien.rect.width)
    row_numbers=calc_row_number(ai_settings, ship.rect.height, alien.rect.height)

    for row_number in range(row_numbers-1):
        for alien_number in range(number_aliens_x-1):
            creat_an_alien(ai_settings,screen,aliens,alien_number,row_number)
        

def creat_an_alien(ai_settings,screen,aliens,alien_number,row_number):
    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
    alien.x=float(alien.rect.x)
    alien.y=float(alien.rect.y)
    aliens.add(alien)

def calc_aliens_number(ai_settings,alien_width):
    #公式计算
    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 calc_row_number(ai_settings, ship_height, alien_height):
    available_space_y = (ai_settings.screen_height -(3 * alien_height) - ship_height)
    number_rows = int(available_space_y / (2 * alien_height))
    return number_rows

#更新外星人
def update_aliens(ai_settings,stats,screen,ship,aliens,bullets):
    check_fleet_edges(ai_settings,aliens)
    aliens.update()
    #
    if pygame.sprite.spritecollideany(ship,aliens):
        ship_hit(ai_settings,stats,screen,ship,aliens,bullets)
        #print("Xiba!!!")

def check_fleet_edges(ai_settings,aliens):
    for alien in aliens.sprites():
        if alien.check_edges():
            change_direction(ai_settings,aliens)
            break

def change_direction(ai_settings,aliens):
    for alien in aliens.sprites():
        alien.y+=ai_settings.fleet_drop_speed
        alien.rect.y=int(alien.y)
    ai_settings.fleet_direction*=-1

def ship_hit(ai_settings,stats,screen,ship,aliens,bullets):
    if stats.ship_lives>0:
        stats.ship_lives-=1

        aliens.empty()
        bullets.empty()

        creat_fleet(ai_settings,screen,ship,aliens)
        ship.center_ship()

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

""" 更新屏幕上的图像，并切换到新屏幕 """
def update_screen(ai_settings, screen, sb,stats, ship, aliens, bullets,play_button):
    #每次循环都重绘屏幕
    screen.fill(ai_settings.bg_color)
    #更新子弹group内子弹位置
    for bullet in bullets.sprites():
        bullet.draw_bullet()
    ship.blitme()
    aliens.draw(screen)
    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:
        sb.prep_score()
        play_button.draw_button()

    # 让最近绘制的屏幕可见
    pygame.display.flip()

 

scoreboard.py

import pygame.font

class Scoreboard():

    def __init__(self,ai_settings,screen,stats):
        self.screen=screen
        self.screen_rect=screen.get_rect()
        self.ai_settings=ai_settings
        self.stats=stats

        #
        self.text_color=(30,30,30)
        self.font=pygame.font.SysFont(None,48)

        #
        self.prep_score()


    def prep_score(self):
        score_str=str(self.stats.score)
        self.score_image=self.font.render(score_str, True, self.text_color,self.ai_settings.bg_color)

        self.score_rect = self.score_image.get_rect()
        self.score_rect.right = self.screen_rect.right - 20
        self.score_rect.top = 20

    def show_score(self):
        self.screen.blit(self.score_image,self.score_rect)

 

button.py

import pygame.font

class Button:
    def __init__(self,ai_settings,screen,msg):
        self.screen=screen
        self.screen_rect=screen.get_rect()

        #设置按钮的大小/颜色/字体
        self.width,self.height=200,50
        self.button_color=(100,100,100)
        self.text_color=(255,255,255)
        self.font=pygame.font.SysFont(None,48)

        #创建按钮的矩形
        self.rect=pygame.Rect(0,0,self.width,self.height)
        self.rect.center=self.screen_rect.center

        #调用prep_msg函数绘制按钮
        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，再绘制文本
         self.screen.fill(self.button_color, self.rect)
         self.screen.blit(self.msg_image, self.msg_image_rect)

 

来源：https://www.cnblogs.com/clno1/p/12485548.html