Provided by: allegro4-doc_4.4.2-10_all bug


       set_alpha_blender   -   Enables  a  special  alpha-channel  blending  mode.  Allegro  game
       programming library.


       #include <allegro.h>

       void set_alpha_blender();


       Enables the special alpha-channel blending mode, which is used  for  drawing  32-bit  RGBA
       sprites.   After   calling   this   function,   you   can   use   draw_trans_sprite()   or
       draw_trans_rle_sprite() to draw a 32-bit  source  image  onto  any  hicolor  or  truecolor
       destination.  The  alpha values will be taken directly from the source graphic, so you can
       vary the solidity of each part of the image. You can't use any of the normal  translucency
       functions  while  this  mode  is  active, though, so you should reset to one of the normal
       blender modes (eg. set_trans_blender()) before drawing anything  other  than  32-bit  RGBA


       set_trans_blender(3alleg4),   draw_trans_sprite(3alleg4),  draw_trans_rle_sprite(3alleg4),
       set_write_alpha_blender(3alleg4), exalpha(3alleg4), exrotscl(3alleg4), extrans(3alleg4)