pygame盒子里的弹珠世界

小小的矩形框内，小珠子弹来弹去。下面是部分代码预览：

"""
   盒子里的弹球小世界
"""
import pygame
from random import randint
from pygame.locals import *

RED = (255,0,0)
BLUE = (0,0,255)

class Ball(pygame.sprite.Sprite):
    """
       球类,继承自角色类,它会在一个矩形范围内受重力移动。
    """
    def __init__(self,radius,box,color):
        """
           radius:半径,box:所在的盒子,color：颜色
        """

    def set_boundary(self):
        """设置反弹的边界"""
        self.left_boundary = self.box.rect.left     # 左边界
        self.right_boundary = self.box.rect.right   # 右边界
        self.top_boundary = self.box.rect.top       # 上边界
        self.bottom_boundary = self.box.rect.bottom # 下边界
        
    def update(self):
        """更新坐标，碰到边缘就反弹。"""


class Box(pygame.sprite.Sprite):
    """
       盒子类，继承自角色类
    """
    def __init__(self,width,height,pos):
        """
           width：宽度，height：高度
        """
    
size = width,height= 640,380
screen = pygame.display.set_mode(size) 
pygame.display.set_caption("盒子里的弹珠世界by lixingqiu")

running = True
while running:
    for event in pygame.event.get():
        if event.type == QUIT:running=False
        
    balls1.update()
    balls2.update()
    screen.fill((20,30,0))
    screen.blit(box1.image,box1.rect)
    screen.blit(box2.image,box2.rect)
    
    balls1.draw(screen)
    balls2.draw(screen)
    
    pygame.display.update()
    clock.tick(30) 

pygame.quit()

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