Topic       : The ATARI Compendium
Author      : Scott Sanders / JAY Software
Version     : 1.25 (20/6/2003)
Subject     : Documentation
Nodes       : 1117
Index Size  : 32614
HCP-Version : 6
Compiled on : Atari
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@lang       : en
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                                GDOS 1.x


GDOS 1.0 and the other 1.x versions which followed it was the original
GDOS developed by Digital Research for Atari. It handled only bitmap fonts
and was slow compared to the newer FONTGDOS which now replaces it.

When a v_opnwk() call is made with GDOS installed, a check is done to see
if a driver was assigned to the device ID specified in the 'ASSIGN.SYS'
file, and if so, loaded.

All VDI calls which specify the returned handle will subsequently be
redirected to the driver.

Not all VDI functions are available with every driver. Check the
'Availability' heading for each specific function in the VDI Function
Reference for specific availability.

Bitmap Fonts

Bitmap fonts have the ability to be quickly rendered and highly accurate.
They do generally require more disk space and a font file must be
available for each point size and aspect ratio required. Bitmap fonts
follow a special naming convention as follows:



The vendor code is a unique two-letter identifier which specifies the
creator of the font. The font code is a two-letter code which abbreviates
the font's name. The point size field specifies the point size of the
font. The device type is a two-letter abbreviation which should match the
aspect ratio of the device as follows:

         Device Type      Destination Ratio

         None or HI       91x91 (Screen Devices)

         CG               91x45 (Screen Devices)

         LS               300x300 (Laser Printers, Inkjets)

         EP               120x144 (Lo-Res Dot-Matrix Printers)

         LB               160x72 (Lo-Res Dot-Matrix Printers)

         SP               180x180 (Med-Res Dot-Matrix Printers)

         QD               240x216 (Med-Res Dot-Matrix Printers)

         NP               360x360 (High-Res Dot-Matrix Printers)

For a driver to recognize a bitmap font it must be listed in the user's
'ASSIGN.SYS' file and be of the correct aspect ratio. No extra fonts are
made available to applications until a vst_load_fonts() call is made.


See also     FONTGDOS, FSM-GDOS, SpeedoGDOS