gistfile1.py

#!/usr/bin/env python

import pygame

pygame.init()

width, height = 500, 500
screen = pygame.display.set_mode((width, height))
running = True
colorRed = (255,0,0)
colorGreen = (0,255,0)
colorBlue = (0,0,255)
green = 0
flip = 0
multiplier = 3


def draw_lines(color, distance):
    for i in range(0,width,distance):
        pygame.draw.aaline(screen, color, (width-i,0), (0,0+i))
        pygame.draw.aaline(screen, color, (width,0+i), (0+i,0))
        pygame.draw.aaline(screen, color, (width-i,height), (0,height-i))
        pygame.draw.aaline(screen, color, (width,height-i), (0+i,height))

while running:
    screen.fill((0,0,0))
    event = pygame.event.poll()
    if event.type == pygame.QUIT:
        running = False
    if green == 255:
        flip = 1
    elif green == 0:
        flip = 0
    if not flip:
        green += multiplier
    if flip:
        green -= multiplier
    Green = (0,green,0)
    draw_lines(Green, 10)
    pygame.display.flip()