al_convert_mask_to_alpha - Man Page

#include <allegro5/allegro.h>

void al_convert_mask_to_alpha(ALLEGRO_BITMAP *bitmap, ALLEGRO_COLOR mask_color)

Convert the given mask color to an alpha channel in the bitmap. Can be used to convert older 4.2-style bitmaps with magic pink to alpha-ready bitmaps.

ALLEGRO_COLOR(3)

al_load_bitmap_font(3).