php man page for set_blender_mode

set_blender_mode(3alleg4)					  Allegro manual					 set_blender_mode(3alleg4)

NAME
       set_blender_mode - Specifies a custom set of truecolor blender routines. Allegro game programming library.

SYNOPSIS
       #include <allegro.h>

       void set_blender_mode(BLENDER_FUNC b15, b16, b24, int r, g, b, a);

DESCRIPTION
       Specifies  a  custom  set of truecolor blender routines, which can be used to implement whatever special interpolation modes you need. This
       function shares a single blender between the 24 and 32-bit modes.

SEE ALSO
       set_blender_mode_ex(3alleg4), set_trans_blender(3alleg4), color_map(3alleg4), draw_trans_sprite(3alleg4),  draw_lit_sprite(3alleg4),  draw-
       ing_mode(3alleg4)

Allegro 							   version 4.4.2					 set_blender_mode(3alleg4)