调用blit方法和pygame.display.update函数时无法渲染Surface对象

Question

I can't say I'm new to pygame. But this is just wierd. I am currenty working on a medium-sized project and while testing I found a wierd bug: Surface object won't render upon calling pygame.display.update()

Using Python 3.7.0

I even tested this:

import pygame
from pygame.locals import *
pygame.init()

s = pygame.display.set_mode((800, 600))
a = pygame.image.load('black_rectangle.png')

while True:
    for event in pygame.event.get():
        if event.type == QUIT:
                pygame.quit()
                quit()
    s.fill((255, 255, 255))
    a.blit(s, (400, 300))
    pygame.display.update()

And all I could see was just a empty white screen.

Answer 1

You are blitting the white s surface onto the black a surface. Just swap s and a .

s.blit(a, (400, 300))