python - Pygame Surface 非顺序更新

Question

我正在尝试实现一个简单的 Pygame 脚本，它应该:

1. 首先，检查用户何时按下 Space 键；
2. 在 Space 键按下时， 显示一些文本；然后
3. 暂停 2 秒然后将屏幕更新到其原始状态。

请注意，上述所有事件必须顺序发生，并且不能乱序。

我遇到的问题是程序首先暂停，然后在屏幕更新到其原始状态之前显示文本仅出现一瞬间(或根本不出现)。

程序似乎跳过了第 2 步，继续执行第 3 步中显示文本之前的暂停。我的代码如下:

import pygame
import sys
from pygame.locals import *

WHITE = (255, 255, 255)
BLACK = (0, 0, 0)

pygame.init()
wS = pygame.display.set_mode((500, 500), 0, 32)


# Method works as intended by itself
def create_text(x, y, phrase, color):
    """
    Create and displays text onto the globally-defined `wS` Surface
    (params in docstring omitted)
    """
    # Assume that the font file exists and is successfully found
    font_obj = pygame.font.Font("./roboto_mono.ttf", 32)
    text_surface_obj = font_obj.render(phrase, True, color)
    text_rect_obj = text_surface_obj.get_rect()
    text_rect_obj.center = (x, y)
    wS.blit(text_surface_obj, text_rect_obj)


while True:
    wS.fill(BLACK)
    for event in pygame.event.get():
        if event.type == KEYDOWN and event.key == K_SPACE:

            # Snippet containing unexpected behavior
            create_text(250, 250, "Hello world!", WHITE)
            pygame.display.update()
            pygame.time.delay(2000)
            # Snippet end

        if event.type == QUIT:
            pygame.quit()
            sys.exit(0)
    pygame.display.update()

提前致谢!

Answer 1

出于某种原因，该程序对我有效，我唯一更改的是字体。这与@Omega0x013 所做的相同，但您拥有无限的帧率。它起作用是因为 FPS.tick() 返回自上次调用以来的时间量，如果您未指定帧速率，则它不会保留程序。

import pygame
import sys
from pygame.locals import *
displayText = False
WHITE = (255, 255, 255)
BLACK = (0, 0, 0)

pygame.init()
wS = pygame.display.set_mode((500, 500), 0, 32)


# Method works as intended by itself
def create_text(x, y, phrase, color):
    """
    Create and displays text onto the globally-defined `wS` Surface
    (params in docstring omitted)
    """
    # Assume that the font file exists and is successfully found

    font_obj = pygame.font.Font(None,30)
    text_surface_obj = font_obj.render(phrase, True, color)
    text_rect_obj = text_surface_obj.get_rect()
    text_rect_obj.center = (x, y)
    wS.blit(text_surface_obj, text_rect_obj)

FPS = pygame.time.Clock()
while True:
    wS.fill(BLACK)
    for event in pygame.event.get():
        if event.type == KEYDOWN and event.key == K_SPACE:
            totalTime = 0
            FPS.tick()
            displayText = True

        if event.type == QUIT:
            pygame.quit()
            sys.exit(0)
    if displayText:
        totalTime += FPS.tick()
        create_text(250, 250, "Hello world!", WHITE)
        if totalTime >= 2000:
            displayText = False
    pygame.display.update()