settings.py

#coding:utf-8
class Settings():
    """存储alien invasion的所有设置的类"""

    def __init__(self):
        """初始化游戏的设置"""
        #屏幕设置
        self.screen_width = 1200
        self.screen_height = 800
        self.bg_color = (230,230,230)
        
        #飞船的设置       
        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
              
        #以什么样的速度加快游戏节奏
        self.speedup_scale = 1.1
        #外星人点数的提高速度
        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_factor = 1.5
        self.bullet_speed_factor = 2
        self.alien_speed_factor = 1
        
        #fleet_direction为1表示右移，-1表示左移
        self.fleet_direction = 1
        
        #记分
        self.alien_points = 50
    
    def increase_speed(self):
        """提高速度设置"""
        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)