🚀 go-pugleaf

I just get a file from comp.sources.atari.st archive at
ssyx.ucsc.edu called "vdit".  This is a file containing a PD
interface to the "undocumented" VDI load_font functions  (not the
regular vst_load_font function which requires GDOS to work).  The
sources in vdit mention that the interface will load fonts in .FED
format.  Back in 1986 I got a PD font editor called GEMFED which can
edit .FED fonts.  The documents for this editor states that GEMFED
is used for editing "GEM fonts".  However, this version of GEMFED is
unable to load the regular GDOS fonts (with .FNT suffix)
which come with easy-draw.   Attempting to rename some .FED fonts
created with GEMFED to .FNT suffix and putting their new names in
assign.sys files to force Easy-Draw to load them as GDOS fonts cause
Easy-Draw to bomb.  Clearly the FED fonts and the regular GDOS .FNT
fonts are not compitable.  My questions are:

1.  What really are "GEM fonts"?  .FED or .Fnt fonts?  What is the
difference between these two?
2.  The vdit file does not mention if the undocumented load_font
function requires GDOS or not.  I assume not.  Thus, can it only
load .FED fonts?  Can it be modified to load the regular GDOS fonts
thus that a program can use this interface to load/use GDOS fonts without
the presence of the GDOS  and the assign.sys trouble?

Any info is appreciated.