set_difference_blender - Enables a difference blender mode. Allegro game programming library.

       Enables  a difference blender mode for combining translucent or lit truecolor pixels. This makes an image
       which has colours calculated by the difference between the source and destination colours.

       set_difference_blender - Enables a difference blender mode. Allegro game programming library.

set_trans_blender(3alleg4), drawing_mode(3alleg4)

Allegro                                           version 4.4.3                  set_difference_blender(3alleg4)

#include<allegro.h>voidset_difference_blender(intr,intg,intb,inta);