I realize that it's not part of standard allegro, but could you consider for next version adding some functions to make color from HSV (Hue, Saturation, Value, known sometimes also as HSL) values? Also values for getting hue, saturation and value from color integer. The reason I'm asking is because with HSV model it is easy to do things like lighting (for 2d games), cool gradients or some of advanced AI (I've seen AI designs based on following objects with certain Hue).