Question

我知道如何在屏幕上显示文本，但是我不喜欢它出现和消失的方式。我希望它淡入淡出。由于存在背景图像，因此无法更改RGB。您能告诉我一个改变文本不透明度的代码吗？

Answer 1

要淡出文本，可以在文本表面上涂抹白色的透明表面，并传递pygame.BLEND_RGBA_MULT特殊标志。

每帧或在特定时间间隔后（减少这些timers）减小（或增加淡入）alpha值，并使用它来填充alpha_surf：

alpha = max(alpha-4, 0)
alpha_surf.fill((255, 255, 255, alpha))

此外，每次更改Alpha时，都要创建原始文本表面的副本，否则会因为原始文本被修改而很快消失。这是一个最小的完整示例：

import pygame as pg


def main():
    clock = pg.time.Clock()
    screen = pg.display.set_mode((640, 480))
    font = pg.font.Font(None, 64)
    blue = pg.Color('royalblue')
    orig_surf = font.render('Enter your text', True, blue)
    txt_surf = orig_surf.copy()
    # This surface is used to adjust the alpha of the txt_surf.
    alpha_surf = pg.Surface(txt_surf.get_size(), pg.SRCALPHA)
    alpha = 255  # The current alpha value of the surface.

    while True:
        for event in pg.event.get():
            if event.type == pg.QUIT:
                return

        if alpha > 0:
            # Reduce alpha each frame, but make sure it doesn't get below 0.
            alpha = max(alpha-4, 0)
            txt_surf = orig_surf.copy()  # Don't modify the original text surf.
            # Fill alpha_surf with this color to set its alpha value.
            alpha_surf.fill((255, 255, 255, alpha))
            # To make the text surface transparent, blit the transparent
            # alpha_surf onto it with the BLEND_RGBA_MULT flag.
            txt_surf.blit(alpha_surf, (0, 0), special_flags=pg.BLEND_RGBA_MULT)

        screen.fill((30, 30, 30))
        screen.blit(txt_surf, (30, 60))
        pg.display.flip()
        clock.tick(30)


if __name__ == '__main__':
    pg.init()
    main()
    pg.quit()

如何在Pygame中淡入和淡出文本

1 个答案: