Does al_draw_tinted_bitmap_region ignore the alpha value in ALLEGRO_COLOR?

    // draws the bitmap normally
    al_draw_tinted_bitmap_region(image, al_map_rgba(255, 255, 255, 255), 0, 0, 40, 40, 0, 0, 0);

    // draws the bitmap normally (same as above)
    al_draw_tinted_bitmap_region(image, al_map_rgba(255, 255, 255, 0), 0, 0, 40, 40, 0, 0, 0);

    // draws the bitmap tinted purple
    al_draw_tinted_bitmap_region(image, al_map_rgba(255, 0, 255, 0), 0, 0, 40, 40, 0, 0, 0);

The code documentation implies that the alpha should affect al_draw_tinted_bitmap_region() like it affects al_draw_tinted_bitmap() ... if it doesn't that's inconvenient.

Which blender are you using? It's pre-multiplied by default:

al_set_blender(ALLEGRO_ADD, ALLEGRO_ONE, ALLEGRO_INVERSE_ALPHA)

which means you have to call: al_map_rgb(r*a,g*a,b*a,a).

Edit: Oh, this is the tinted functions. Not sure how those work, or if any of the above applies.

I have yet to explicitly use a blender. Passing an ALLEGRO_COLOR has pretty much been doing it for me ...

Looks like I'm right. See thread discussions on the al_draw_tinted_bitmap() page.

Hmmm. That's a little odd IMHO, but ... okay! It does work ...

It's okay. I'll be answering this same question for the rest of my life.

In return you'll never have to answer questions about why sprites get mysterious dark outlines