python第13章实例

# _*_ coding:utf-8 _*_
import sys
import pygame

pygame.init()
size = width,height = 640, 480
screen = pygame.display.set_mode(size)
color =(0,0,0)

ball = pygame.image.load("ball.png")
ballrect = ball.get_rect()

speed = [5,5]
clock = pygame.time.Clock()

while True:
clock.tick(60)
for event in pygame.event.get():
if event.type == pygame.QUIT:
pygame.quit()
sys.exit()

ballrect = ballrect.move(speed)
if ballrect.left<0 or ballrect.right> width:
speed[0] = -speed[0]
if ballrect.top <0 or ballrect.bottom> height:
speed[1] = -speed[1]

screen.fill(color)
screen.blit(ball,ballrect)
pygame.display.flip()