Pygame proble, moving picture

Question

Thats my problem on the Picture...The stripes

How can i fix that?

My Code:

import pygame, sys from pygame.locals import *

pygame.init()

sound = pygame.mixer.Sound('start.wav') sound.play()

size = width, height = 1600, 848 speed = [2, 2] black = (0, 0, 0)

pygame.mouse.set_cursor(*pygame.cursors.broken_x)

screen = pygame.display.set_mode(size) background = pygame.image.load("background.PNG") dragon1 = pygame.image.load("dragon1.gif") screen.blit(background, (0,0))

x,y=0,0 clock=pygame.time.Clock() speed=250 movex, movey=0,0

while True: for event in pygame.event.get(): if event.type == QUIT: pygame.quit() sys.exit() if event.type==KEYDOWN: if event.key==K_a: movex=-1 elif event.key==K_d: movex=+1 elif event.key==K_w: movey=-1 elif event.key==K_s: movey=+1 if event.type==KEYUP: if event.key==K_a: movex=0 elif event.key==K_d: movex=0 elif event.key==K_w: movey=0 elif event.key==K_s: movey=0 x+=movex y+=movey

screen.blit(dragon1, (x,y))
pygame.display.flip()

Answer 1

You need to blit the background image at each update or loop in your mainloop like so:

while True:
    #mainloop stuff
    screen.blit(background, (0,0))
    screen.blit(dragon1, (x,y))
    pygame.display.flip()

The way you are currently doing it you are only blitting the BG once then you are blitting the dragon but the screen isnt being refreshed so you keep seeing each place the dragon was blitted at before