Python編程：從入門到實踐 項目《外星人入侵》完整代碼

學習《Python編程：從入門到實踐》有段時間了，跟着書本把所有代碼都敲了一遍，感悟很深，現在完成了《外星人入侵》項目，對於庫、類、函數、方法都有一定的理解，現在將該項目完整代碼分享出來，以供學習。

1.首先當然是主運行文件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、設置和屏幕對象
    pygame.init()
    ai_settings = Settings()
    screen = pygame.display.set_mode(
        (ai_settings.screen_width,ai_settings.screen_height))
    pygame.display.set_caption("Alien Invasion")
    
    # 創建Play按鈕
    play_button = Button(ai_settings, screen, "Play")
    
    # 創建存儲游戲統計信息的實例，並創建記分牌
    stats = GameStats(ai_settings)
    sb = Scoreboard(ai_settings, screen, stats)
    
    #創建一艘飛船、一個子彈編組和一個外星人編組
    ship = Ship(ai_settings,screen)
    bullets = Group()
    aliens = Group()
    
    # 創建外星人群
    gf.create_fleet(ai_settings,screen,ship,aliens)
    
    # 開始游戲的主循環
    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,stats,screen,sb,ship,aliens,bullets)

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

run_game()

　　

2.游戲相關參數設置settings.py

class Settings(): 
    """存儲《外星人入侵》的所有設置的類""" 
    def __init__(self): 
        """初始化游戲的靜態設置""" 
        # 屏幕設置
        self.screen_width = 800 
        self.screen_height = 600 
        self.bg_color = (230, 230, 230)
        
        # 飛船的設置
        self.ship_speed_factor = 0.3
        
        #子彈設置
        self.bullet_speed_factor = 1
        self.ship_limit = 3
        self.bullet_width = 3
        self.bullet_height = 15
        self.bullet_color = 60,60,60
        self.bullets_allowed = 3

		# 外星人設置
        self.alien_speed_factor = 0.1
        self.fleet_drop_speed = 10
        
        # 以什么樣的速度加快游戲節奏
        self.speedup_scale = 1.01
        # 外星人點數的提高速度
        self.score_scale = 1.1

        self.initialize_dynamic_settings()
        
		# fleet_direction為1表示向右移，為-1表示向左移
        self.fleet_direction = 1

    def initialize_dynamic_settings(self): 
        """初始化隨游戲進行而變化的設置""" 
        self.ship_speed_factor = 0.3 
        self.bullet_speed_factor = 1 
        self.alien_speed_factor = 0.1
        
        # fleet_direction為1表示向右；為-1表示向左
        self.fleet_direction = 1
        
        # 記分
        self.alien_points = 50
    
    def increase_speed(self): 
        """提高速度設置和外星人點數""" 
        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)

　　

3.按鍵及事件邏輯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):
    """響應按鍵"""
    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_UP:
        ship.moving_up = True
    elif event.key == pygame.K_DOWN:
        ship.moving_down = True
    elif event.key == pygame.K_SPACE:
        fire_bullet(ai_settings,screen,ship,bullets)
    elif event.key == pygame.K_q:
        sys.exit()
        
def fire_bullet(ai_settings,screen,ship,bullets):
    """如果還沒有到達限制，就發射一顆子彈"""
    # 創建一顆子彈，並將其加入到編組bullets中
    if len(bullets) < ai_settings.bullets_allowed:
        new_bullet = Bullet(ai_settings,screen,ship)
        bullets.add(new_bullet)

def check_keyup_events(event,ship):
    """響應松開"""
    if event.key == pygame.K_RIGHT:
        ship.moving_right = False
    elif event.key == pygame.K_LEFT:
        ship.moving_left = False
    elif event.key == pygame.K_UP:
        ship.moving_up = False
    elif event.key == pygame.K_DOWN:
        ship.moving_down = False

def check_events(ai_settings,screen,stats,sb,play_button,ship,aliens,
        bullets):
    """響應按鍵和鼠標事件"""
    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, 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): 
    """在玩家單擊Play按鈕時開始新游戲"""
    button_clicked = play_button.rect.collidepoint(mouse_x, mouse_y)
    if button_clicked and not stats.game_active:
        # 重置游戲設置
        ai_settings.initialize_dynamic_settings() 
        
        # 隱藏光標
        pygame.mouse.set_visible(False) 
        
        # 重置游戲統計信息
        stats.reset_stats()
        stats.game_active = True
        
        # 重置記分牌圖像
        sb.prep_score()
        sb.prep_high_score()
        sb.prep_level()
        sb.prep_ships()

        # 清空外星人列表和子彈列表
        aliens.empty() 
        bullets.empty()
        
        # 創建一群新的外星人，並讓飛船居中
        create_fleet(ai_settings, screen, ship, aliens) 
        ship.center_ship()

def update_bullets(ai_settings,screen,stats,sb,ship,aliens,bullets):
    """更新子彈的位置，並刪除已消失的子彈"""
    # 更新子彈的位置
    bullets.update()

    # 刪除已消失的子彈
    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_bullet_alien_collisions(ai_settings, screen, stats, sb, ship,
        aliens, bullets):
    """響應子彈和外星人的碰撞"""
    # 刪除發生碰撞的子彈和外星人
    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:
        # 如果整群外星人都被消滅，就提高一個等級
        bullets.empty()
        ai_settings.increase_speed()
        
        # 提高等級
        stats.level += 1
        sb.prep_level()
        
        create_fleet(ai_settings, screen, ship, aliens) 

def update_screen(ai_settings,screen,stats,sb,ship,aliens,bullets,
        play_button):
    """更新屏幕上的圖像，並切換到新屏幕"""
    #每次循環時都重繪屏幕
    screen.fill(ai_settings.bg_color)
    # 在飛船和外星人后面重繪所有子彈
    for bullet in bullets.sprites():
        bullet.draw_bullet()
    ship.blitme()
    aliens.draw(screen)
    
    # 顯示得分
    sb.show_score() 

    # 如果游戲處於非活動狀態，就繪制Play按鈕
    if not stats.game_active: 
        play_button.draw_button() 

    # 讓最近繪制的屏幕可見
    pygame.display.flip()

def get_number_aliens_x(ai_settings, alien_width): 
	"""計算每行可容納多少個外星人""" 
	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 get_number_rows(ai_settings, ship_height, alien_height): 
	"""計算屏幕可容納多少行外星人"""
	available_space_y = (ai_settings.screen_height - 
							(3 * alien_height) - ship_height) 
	number_rows = int(available_space_y / (3 * alien_height))
	return number_rows

def create_alien(ai_settings, screen, aliens, alien_number, row_number): 
	"""創建一個外星人並將其放在當前行""" 
	alien = Alien(ai_settings, screen)
	alien_width = alien.rect.width
	alien.x = alien_width + 2 * alien_width * alien_number
	alien.rect.y = alien.rect.height + 2 * alien.rect.height * row_number
	alien.rect.x = alien.x
	aliens.add(alien)
	
def create_fleet(ai_settings, screen, ship, aliens): 
	"""創建外星人群""" 
	# 創建一個外星人，並計算每行可容納多少個外星人
	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) 
  
	# 創建外星人群
	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_fleet_edges(ai_settings, aliens): 
    """有外星人到達邊緣時采取相應的措施""" 
    for alien in aliens.sprites(): 
        if alien.check_edges(): 
            change_fleet_direction(ai_settings, aliens) 
            break 
  
def change_fleet_direction(ai_settings, aliens): 
    """將整群外星人下移，並改變它們的方向""" 
    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, sb, ship, aliens, bullets): 
    """響應被外星人撞到的飛船"""
    if stats.ships_left > 0:
        # 將ships_left減1 
        stats.ships_left -= 1
        
        # 更新記分牌
        sb.prep_ships() 
          
        # 清空外星人列表和子彈列表
        aliens.empty() 
        bullets.empty() 
          
        # 創建一群新的外星人，並將飛船放到屏幕底端中央
        create_fleet(ai_settings, screen, ship, aliens) 
        ship.center_ship() 
          
        # 暫停
        sleep(0.5)
    
    else:
        stats.game_active = False
        pygame.mouse.set_visible(True)

def check_aliens_bottom(ai_settings, stats, screen, sb, ship, aliens, bullets): 
    """檢查是否有外星人到達了屏幕底端""" 
    screen_rect = screen.get_rect() 
    for alien in aliens.sprites():
        if alien.rect.bottom >= screen_rect.bottom: 
            # 像飛船被撞到一樣進行處理
            ship_hit(ai_settings, stats, screen, sb, ship, aliens, bullets) 
            break

def check_high_score(stats, sb): 
    """檢查是否誕生了新的最高得分""" 
    if stats.score > stats.high_score: 
        stats.high_score = stats.score 
        sb.prep_high_score()

def update_aliens(ai_settings, stats, screen, sb, ship, aliens, bullets): 
    """ 
    檢查是否有外星人位於屏幕邊緣，並更新整群外星人的位置
    """
    check_fleet_edges(ai_settings, aliens)
    aliens.update()
    
    # 檢測外星人和飛船之間的碰撞
    if pygame.sprite.spritecollideany(ship, aliens):
        ship_hit(ai_settings, stats, screen, sb, ship, aliens, bullets)
    
    # 檢查是否有外星人到達屏幕底端
    check_aliens_bottom(ai_settings, stats, screen, sb, ship, aliens, bullets)

　　

4.計分相關設置scoreboard.py

import pygame.font
from pygame.sprite import Group

from ship import Ship

class Scoreboard():
    """顯示得分信息的類"""

    def __init__(self, ai_settings, screen, stats): 
        """初始化顯示得分涉及的屬性""" 
        self.screen = screen 
        self.screen_rect = screen.get_rect() 
        self.ai_settings = ai_settings 
        self.stats = stats
          
        # 顯示得分信息時使用的字體設置
        self.text_color = (30, 30, 30)
        self.font = pygame.font.SysFont(None, 48)

        # 准備包含最高得分和當前得分的圖像
        self.prep_score()
        self.prep_high_score()
        self.prep_level()
        self.prep_ships()

    def prep_score(self): 
        """將得分轉換為一幅渲染的圖像"""
        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) 

        # 將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 

    def prep_high_score(self): 
        """將最高得分轉換為渲染的圖像""" 
        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) 
        
        #將最高得分放在屏幕頂部中央
        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): 
        """將等級轉換為渲染的圖像"""
        self.level_image = self.font.render(str(self.stats.level), True, 
                self.text_color, self.ai_settings.bg_color)
        
        # 將等級放在得分下方
        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): 
        """顯示還余下多少艘飛船"""
        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): 
        """在屏幕上顯示飛船和得分""" 
        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)
        # 繪制飛船
        self.ships.draw(self.screen)

　　

5.跟蹤游戲統計信息

class GameStats():
    """跟蹤游戲的統計信息"""
    
    def __init__(self, ai_settings): 
        """初始化統計信息""" 
        self.ai_settings = ai_settings
        self.reset_stats()
        # 游戲剛啟動時處於活動狀態
        self.game_active = False
        
        # 在任何情況下都不應重置最高得分
        self.high_score = 0 
        
    def reset_stats(self): 
        """初始化在游戲運行期間可能變化的統計信息""" 
        self.ships_left = self.ai_settings.ship_limit
        self.score = 0
        self.level = 1
        

　　

6.“游戲開始”按鍵設置button.py

import pygame.font

class Button():
    
    def __init__(self, ai_settings, screen, msg):
        """初始化按鈕的屬性"""
        self.screen = screen
        self.screen_rect = screen.get_rect()

        # 設置按鈕的尺寸和其他屬性
        self.width, self.height = 200, 50
        self.button_color = (0, 255, 0)
        self.text_color = (255, 255, 255)
        self.font = pygame.font.SysFont('arial', 48)
          
        # 創建按鈕的rect對象，並使其居中
        self.rect = pygame.Rect(0, 0, self.width, self.height)
        self.rect.center = self.screen_rect.center
          
        # 按鈕的標簽只需創建一次
        self.prep_msg(msg)

    def prep_msg(self, msg): 
        """將msg渲染為圖像，並使其在按鈕上居中"""
        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): 
        # 繪制一個用顏色填充的按鈕，再繪制文本
        self.screen.fill(self.button_color, self.rect) 
        self.screen.blit(self.msg_image, self.msg_image_rect) 

　　

7.飛船相關設置ship.py

import pygame
from pygame.sprite import Sprite

class Ship(Sprite):

    def __init__(self, ai_settings,screen):
        """初始化飛船並設置其初始位置"""
        super(Ship,self).__init__()
        self.screen = screen
        self.ai_settings = ai_settings
        
        # 加載飛船圖像並獲取其外接矩形
        self.image = pygame.image.load('images/ship.bmp')
        self.rect = self.image.get_rect()
        self.screen_rect = screen.get_rect()

        # 將每艘新飛船放在屏幕底部中央
        self.rect.centerx = self.screen_rect.centerx 
        self.rect.bottom = self.screen_rect.bottom

        # 在飛船的屬性center中存儲小數值
        self.center = float(self.rect.centerx)
        self.centery = float(self.rect.centery)

        # 移動標志
        self.moving_right = False
        self.moving_left = False
        self.moving_up = False
        self.moving_down = False
        
    def update(self):
        """根據移動標志調整飛船的位置"""
        # 更新飛船的center值,而不是rect
        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
            
        if self.moving_up and self.rect.top > 0:
            self.centery -= self.ai_settings.ship_speed_factor
        if self.moving_down and self.rect.bottom < self.screen_rect.bottom:
            self.centery += self.ai_settings.ship_speed_factor

        # 根據self.center更新rect對象
        self.rect.centerx = self.center
        self.rect.centery = self.centery

    def center_ship(self): 
        """讓飛船在屏幕上居中""" 
        self.center = self.screen_rect.centerx
        self.centery = self.screen_rect.bottom
        
    def blitme(self):
        """在指定位置繪制飛船""" 
        self.screen.blit(self.image,self.rect) 

　　

8.外星人相關設置alien.py

import pygame
from pygame.sprite import Sprite

class Alien(Sprite): 
    """表示單個外星人的類"""

    def __init__(self, ai_settings, screen): 
        """初始化外星人並設置其起始位置""" 
        super(Alien, self).__init__() 
        self.screen = screen 
        self.ai_settings = ai_settings
        
        # 加載外星人圖像，並設置其rect屬性
        self.image = pygame.image.load('images/alien.bmp') 
        self.rect = self.image.get_rect()

        # 每個外星人最初都在屏幕左上角附近
        self.rect.x = self.rect.width 
        self.rect.y = self.rect.height

        # 存儲外星人的准確位置
        self.x = float(self.rect.x)
        
    def blitme(self): 
        """在指定位置繪制外星人""" 
        self.screen.blit(self.image, self.rect)

    def check_edges(self): 
        """如果外星人位於屏幕邊緣，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): 
        """向左或右移動外星人""" 
        self.x += (self.ai_settings.alien_speed_factor * 
                    self.ai_settings.fleet_direction)
        self.rect.x = self.x 

　　

9.子彈相關設置bullet.py

import pygame 
from pygame.sprite import Sprite

class Bullet(Sprite): 
    """一個對飛船發射的子彈進行管理的類"""
    
    def __init__(self, ai_settings, screen, ship): 
        """在飛船所處的位置創建一個子彈對象""" 
        super(Bullet, self).__init__() 
        self.screen = screen

        # 在(0,0)處創建一個表示子彈的矩形，再設置正確的位置
        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

        #存儲用小數表示的子彈位置
        self.y = float(self.rect.y)

        self.color = ai_settings.bullet_color 
        self.speed_factor = ai_settings.bullet_speed_factor
        
    def update(self): 
        """向上移動子彈""" 
        #更新表示子彈位置的小數值
        self.y -= self.speed_factor 
        #更新表示子彈的rect的位置
        self.rect.y = self.y
        
    def draw_bullet(self): 
        """在屏幕上繪制子彈""" 
        pygame.draw.rect(self.screen, self.color, self.rect) 

　　

關於ship.py文件中
self.image = pygame.image.load(‘images/ship.bmp’)
和alien.py文件中
self.image = pygame.image.load(‘images/alien.bmp’)
代碼里的圖片，需要各位自行在根目錄下新建文件夾和圖像

另外，自己在調試項目的過程中，常常有報錯，其中主要錯誤的反而是忘了下划線、冒號還有代碼縮進，代碼縮進要么完全使用空格，要么全都使用tab進行縮進，python在識別縮進上非常嚴格。

寫給自己，也分享給大家。

原文：https://blog.csdn.net/kenidi8215/article/details/88862701