is_trans_font  - Returns TRUE if a font uses transparency. Allegro game
       programming library.
       #include <allegro.h>
       int is_trans_font(FONT *f)
       This  function  checks  if  the  given  font  is  a  color  font  using
       draw_trans_sprite to render glyphs.
       Returns TRUE if the font uses transparency, FALSE if it does not.
       make_trans_font(3alleg), is_color_font(3alleg), is_mono_font(3alleg)