Должно быть внутри цикла:
x1 += x1_change
y1 += y1_change
dis.fill(white)
pygame.draw.rect(dis, black, [x1, y1, 10, 10])
pygame.display.update()
clock.tick(30)
Код:while not game_over:
for event in pygame.event.get():
if event.type == pygame.QUIT:
game_over = True
if event.type == pygame.KEYDOWN:
if event.key == pygame.K_LEFT:
x1_change = -10
y1_change = 0
elif event.key == pygame.K_RIGHT:
x1_change = 10
y1_change = 0
elif event.key == pygame.K_UP:
y1_change = -10
x1_change = 0
elif event.key == pygame.K_DOWN:
y1_change = 10
x1_change = 0
x1 += x1_change
y1 += y1_change
dis.fill(white)
pygame.draw.rect(dis, black, [x1, y1, 10, 10])
pygame.display.update()
clock.tick(30)