Pygame小球游戏

import sys
import  pygame
pygame.init()
size = width, height = 1000, 800
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(70)
    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.right >height:
        speed[1] = -speed[1]
    screen.fill(color)
    screen.blit(ball, ballrect)
    pygame.display.flip()