PyGame 中的闪烁文本

Question

如何在 PyGame 中制作闪烁的文本？这是我尝试每秒闪烁一次的文本：

text = pygame.font.Font("c:/windows/fonts/visitor1.ttf", 50)

textsurf, textrect = text_objects("Press Any Key To Start", text)

textrect.center = ((res_w / 2), (res_h / 2))

screen.blit(textsurf, textrect)

Answer 1

为了让它闪烁，你必须画一秒钟然后删除它一秒钟，一遍又一遍地重复这个。可以使用自定义计时器事件来计时闪烁。

#!/usr/bin/env python
# coding: utf8
from __future__ import absolute_import, division, print_function
from itertools import cycle
import pygame

VISITOR_TTF_FILENAME = '/usr/share/fonts/truetype/aenigma/visitor1.ttf'
BLINK_EVENT = pygame.USEREVENT + 0


def main():
    pygame.init()
    try:
        screen = pygame.display.set_mode((800, 600))
        screen_rect = screen.get_rect()

        clock = pygame.time.Clock()

        font = pygame.font.Font(VISITOR_TTF_FILENAME, 50)
        on_text_surface = font.render(
            'Press Any Key To Start', True, pygame.Color('green3')
        )
        blink_rect = on_text_surface.get_rect()
        blink_rect.center = screen_rect.center
        off_text_surface = pygame.Surface(blink_rect.size)
        blink_surfaces = cycle([on_text_surface, off_text_surface])
        blink_surface = next(blink_surfaces)
        pygame.time.set_timer(BLINK_EVENT, 1000)

        while True:
            for event in pygame.event.get():
                if event.type == pygame.QUIT:
                    return
                if event.type == BLINK_EVENT:
                    blink_surface = next(blink_surfaces)

            screen.blit(blink_surface, blink_rect)
            pygame.display.update()
            clock.tick(60)
    finally:
        pygame.quit()


if __name__ == '__main__':
    main()

除了在关闭阶段完全变黑之外，还可以将文本以较深的颜色进行 blit。

如果在初始化和主循环中还有更多内容，则将闪烁文本封装在派生自 Pygame 的 Sprite 的类型中可能有助于保持代码清晰。

Answer 2

我和@BlackJack https://stackoverflow.com/users/3815611/blackjack做了同样的事情 但我让 off_text_surface 透明：

from __future__ import absolute_import, division, print_function
from itertools import cycle
import pygame

VISITOR_TTF_FILENAME = 'pixelFont.ttf'
BLINK_EVENT = pygame.USEREVENT + 0
empty = (255,255,255,0)


def main():
    pygame.init()
    try:
        screen = pygame.display.set_mode((800, 600))
        screen.fill((255,255,255))
        screen_rect = screen.get_rect()

        clock = pygame.time.Clock()

        font = pygame.font.Font(VISITOR_TTF_FILENAME, 50)
        on_text_surface = font.render(
            'Press Any Key To Start', True, pygame.Color('green3')
        )
        blink_rect = on_text_surface.get_rect()
        blink_rect.center = screen_rect.center
        off_text_surface = pygame.Surface(blink_rect.size)
        off_text_surface.fill(empty)
        
        blink_surfaces = cycle([on_text_surface, off_text_surface])
        blink_surface = next(blink_surfaces)
        pygame.time.set_timer(BLINK_EVENT, 1000)

        while True:
            for event in pygame.event.get():
                if event.type == pygame.QUIT:
                    return
                if event.type == BLINK_EVENT:
                    blink_surface = next(blink_surfaces)

            screen.blit(blink_surface, blink_rect)
            pygame.display.update()
            clock.tick(60)
    finally:
        pygame.quit()


if __name__ == '__main__':
    main()