如何在此代码中添加背景而不会出错？

Question

def game():
running = True
while running:
    screen.fill((0, 0, 0))
    mx, my = pygame.mouse.get_pos()
    button_3 = pygame.Rect(300, 100, 1300, 700)
    if button_3.collidepoint((mx, my)):
        if click:
            begin()

    draw_text('game', font, (255, 255, 255), screen, 20, 20)
    for event in pygame.event.get():
        if event.type == QUIT:
            pygame.quit()
            sys.exit()
        if event.type == KEYDOWN:
            if event.key == K_ESCAPE:
                running = False


    # set the pygame window name

    img1 = pygame.image.load(r"C:\Users\ga-sa\Downloads\As.png")
    img2 = pygame.image.load(r"C:\Users\ga-sa\Downloads\AssetsXOR.png")
    img3 = pygame.image.load(r"C:\Users\ga-sa\Downloads\AssetsNOT.png")
    img4 = pygame.image.load(r"C:\Users\ga-sa\Downloads\AssetsAND.png")

    images = [img1, img2, img3, img4]

    current_image = -1
    img_rects = [images[i].get_rect(topleft=(20 + 40 * i, 20)) for i in range(len(images))]

    LeftButton = 0
    while 1:
        for e in pygame.event.get():
            if e.type == QUIT:
                pygame.quit()
                exit(0)

            if e.type == pygame.MOUSEBUTTONDOWN:
                mouse_rect = pygame.Rect(e.pos, (1, 1))
                current_image = mouse_rect.collidelist(img_rects)

            if e.type == MOUSEMOTION:
                if e.buttons[LeftButton]:
                    rel = e.rel
                    if 0 <= current_image < len(images):
                        img_rects[current_image].x += rel[0]
                        img_rects[current_image].y += rel[1]

        screen.fill(0)
        for i in range(len(images)):
            screen.blit(images[i], img_rects[i])
        pygame.display.flip()
        pygame.time.delay(30)

    screen.blit(BACKGROUND_FASE, (0, 0))
    pygame.display.update()
    mainClock.tick(60)

我想在这个屏幕上添加背景图片，但是每次尝试都出错或者没有出现，请问如何才能不出错地给那部分添加背景，另一部分代码是一个菜单，当我点击开始时会出现这个屏幕，整个代码在这里 https://pastebin.com/Rb7jh2GH

Answer 1

你必须在绘制场景之前 blit 背景，并且你必须在你的游戏循环中绘制它。当你绘制背景时，它会覆盖之前绘制的所有内容：

绘制背景
绘制场景（所有物体）
更新显示

注意绘制背景图时不需要清除背景。如果背景图覆盖了整个window，则无需清除背景。

~~screen.fill(0)~~

while running:
    # [...]

    while 1:
        for e in pygame.event.get():
            if e.type == QUIT:
                pygame.quit()
                exit(0)

        # [...]

        # draw background
        # screen.fill(0)  <--- superfluous
        screen.blit(BACKGROUND_FASE, (0, 0))

        # draw scene (objects)
        for i in range(len(images)):
            screen.blit(images[i], img_rects[i])

        # update display
        pygame.display.flip()

如何在此代码中添加背景而不会出错？

how to add a background in this code without errors?

python

pygame

pygame-surface