弹跳球

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("th.jpg")
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:
sys.exit()
ballrect = ballrect.move(speed)
if ballrect.left <0 or ballrect.right > width:
speed[0] = -speed[1]
if ballrect.top <0 or ballrect.bottom > height:
speed[1] = -speed[1]
screen.fill(color)
screen.blit(ball, ballrect)
pygame.display.flip()
pygame.quit()