pygame: create mask form png with transparancy

Question

I searched around but found nothing helpfull.

I have in pygame an png image as a player, with a transparant background. I want to create a mask of only the player not the background. I can do this but I get a rectangle as a mask, instead of the player's shape.

how can I solve this?

here is my code:

import pygame
import os

pygame.init()

# Create display
screen_width=1600
screen_height=960

screen = pygame.display.set_mode((screen_width, screen_height),pygame.NOFRAME)

# Set framerate
clock = pygame.time.Clock()
fps = 60

#load images
player_img=pygame.image.load('img/player/Idle/1.png').convert_alpha()
player_mask=pygame.mask.from_surface(player_img)
player_maskSurf=pygame.Surface((player_img.get_width(),player_img.get_height()),masks=player_mask)

#define colors
BG=(124,64,204)
red = (255,0,0)
blue = (0,0,255)

run = True
while run:

    clock.tick(fps)
    screen.fill(BG)

    screen.blit(player_img, (800-player_img.get_width()/2,480-player_img.get_height()/2))
    screen.blit(player_maskSurf, (800-player_img.get_width()/2,480-player_img.get_height()/2))

    for event in pygame.event.get():
        #quit game
        if event.type == pygame.QUIT:
            run = False
        #keyboard presses
        if event.type==pygame.KEYDOWN:
            if event.key == pygame.K_ESCAPE:
                run = False

    pygame.display.update()

pygame.quit()

Thank you

Answer 1

The mask argument of a Surface is not considered to be a pygame.Mask object. See pygame.Surface:

[...] The masks are a set of 4 integers representing which bits in a pixel will represent each color. Normal Surfaces should not require the masks argument.

---

Use pygame.mask.Mask.to_surface to convert a pygame.Mask to a pygame.Surface:

player_maskSurf=pygame.Surface((player_img.get_width(),player_img.get_height()),masks=player_mask)

player_maskSurf = player_mask.to_surface()
player_maskSurf.set_colorkey((0, 0, 0)) # this is optional