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

       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.

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

set_blender_mode_ex(3alleg4), set_trans_blender(3alleg4), color_map(3alleg4), draw_trans_sprite(3alleg4),
       draw_lit_sprite(3alleg4), drawing_mode(3alleg4)

Allegro                                           version 4.4.3                        set_blender_mode(3alleg4)

#include<allegro.h>voidset_blender_mode(BLENDER_FUNCb15,b16,b24,intr,g,b,a);