draw_character_ex (3) - Linux Man Pages
draw_character_ex: Draws non transparent pixels of the sprite with a color. Allegro game programming library.
NAMEdraw_character_ex - Draws non transparent pixels of the sprite with a color. Allegro game programming library.
DESCRIPTIONDraws a copy of the sprite bitmap onto the destination bitmap at the specified position, drawing transparent pixels in the background color (or skipping them if the background color is -1) and setting all other pixels to the specified color. Transparent pixels are marked by a zero in 256-color modes or bright pink for truecolor data (maximum red and blue, zero green). The sprite must be an 8-bit image, even if the destination is a truecolor bitmap. Example:
BITMAP *logo; ... /* Draw the logo silhouette in red. */ draw_character_ex(screen, logo, SCREEN_W / 2, SCREEN_H / 2, makecol(255, 0, 0), -1);