Hallo Allerseits!
Gibts eigentlich die DECUS Library noch?
Zitiere mal aus: https://ilkerf.tripod.com/cdoc/decregis.html
To help you develop ReGIS applications, you can use the ReGIS Graphics Library (RGL) by Richard Desper of the U.S. Army Materials Technology Laboratory. This is available from the DECUS Software Library as V00365; it allows you to make high-level calls to ReGIS primitives.
The FORTRAN source code for VMS is available thusly
ftp://www.decus.org/pub/lib/v00365/vaxregis.zip
This Zip file is 990467 bytes. Be sure to transfer in binary mode.
Kurzes googeln bringt nichts sinnvolles zu Tage....