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pythontextpygametransparencypygame-surface

Transparency problem displaying text with Pygame

enter image description hereI would like to display transparent text on a surface that is sized based on the length of the text. The problem is that the text has a black background even though "None" is specified as the background in the "render" command. I tried to apply the solutions given for questions similar to mine but they didn't work. I attach the code and thank you for any suggestions.

import pygame
from pygame.locals import *

pygame.init()
screen = pygame.display.set_mode((800, 600))
screen.fill ((0,0,255))

# red square
surf1 = pygame.Surface((200, 200))
surf1.fill((255, 0, 0))
rect1 = surf1.get_rect()
rect1.topleft = (50, 50)
screen.blit(surf1, rect1)

# Play button
fnt = pygame.font.SysFont("Times New Roman", 27, bold=True)
btn_play = fnt.render("Play", True, (51, 26, 0), None)
btn_play_size = btn_play.get_size()
btn_play_surface = pygame.Surface(btn_play_size)
btn_play_surface.blit(btn_play, (0, 0))
rect_btn_play = pygame.Rect(380, 50, btn_play_size[0], btn_play_size[1])
screen.blit(btn_play_surface, (380, 50))
pygame.display.flip()

def events():
    done = False
    while not done:
        for ev in pygame.event.get():
            if ev.type == QUIT:
                return "quit"
            elif ev.type == MOUSEBUTTONDOWN:
                click = ev.pos
                if rect1.collidepoint(click):
                    return "Red squre"
                elif rect_btn_play.collidepoint(click):
                    return "Play"
                else:
                    print ("You clicked outside of the surfaces")

while True:
    event = events()
    print (event)
    if event == "quit":
        break
pygame.quit()
Solution

  • The problem is the surface you are placing the text on. If you want to keep the transparency in the formation of the text, you need to create a pygame.Surface object with an per pixel alpha format. Use the pygame.SRCALPHA flag:

    btn_play_surface = pygame.Surface(btn_play_size)

    btn_play_surface = pygame.Surface(btn_play_size, pygame.SRCALPHA)

    Alternatively you can set the color key for the transparent color with set_colorkey:

    btn_play_surface = pygame.Surface(btn_play_size)
btn_play_surface.set_colorkey((0, 0, 0))

    enter image description here