Pygame - blitting to screen producing weird results? -


i have blitted image screen of program, worked fine, when tried 'animate' it, produces weird results. seems updating position produces image , on...

code input:

screen=pygame.display.set_mode((640,360),0,32) star=pygame.image.load("star.png").convert_alpha()  x = randint(80,700) y = randint(-200,-200)  while true:     event in pygame.event.get():         if event.type == quit:             pygame.quit()             sys.exit()      x-=0.1     y+=0.1     screen.blit(star,(x,y))      if y > 360:         y = randint(-200,-200)         x = randint(80,700)         screen.fill((0,0,0))      pygame.display.update()

outcome:

http://imgur.com/i28od5b

i appreciate feedback why happens , how can fix it.

you don't blank canvas every frame. need erase old star before drawing new one.

you can see account in pygame tutorials.


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