#!/usr/bin/env python

#original code from Game Development with Python and Pygame by Will McGugan

import pygame
from pygame.locals import *
from sys import exit


from random import *

pygame.init()
screen = pygame.display.set_mode((640, 480), 0, 16)

j = 0

while True:
        
    for event in pygame.event.get():
        if event.type == QUIT:
            exit()
    if (j%640 == 0):
		screen.fill((0,0,0))        
    random_color = (randint(0,255), randint(0,255), 0)        
    #random_pos = (randint(0,639), 240)
    random_pos = (j%640, 240+ 20)
    random_pos2 = (640 - j%640, 80)
    random_pos3 = (640 - j%640, 410)
    random_radius = randint(5,75)
    pygame.draw.circle(screen, random_color, random_pos, random_radius)
    pygame.draw.circle(screen, random_color, random_pos2, random_radius/2)
    pygame.draw.circle(screen, random_color, random_pos3, random_radius/2)

    j = j+5
        
    pygame.display.update()