Subject: Re: vogle

From: Lance Norskog <[email-masked]>
Date: 9 Oct 91 17:19:45 PDT (Wed)

The VOGLE and VOGL libraries are on uunet.uu.net in 
/usr/spool/ftp/graphics/vogle.  They're from an Australian
university, and are copyright-but-free.  They're a software
version of SGI's GL core graphics library, written from scratch
with drivers for lots of frame buffers: X windows, all PC
adapters, a Mac version somewhere, Sun, Apollo, and postscript
commands.

VOGLE is the main one.  They were inspired to change a few
things to make it exactly compatible with GL, and called that
VOGL.  If you want portability to SGI machines, stick with VOGL.

It has a lot of nifty calls, and an object data structure.
Objects can have their own personal translation matrices.
They can call other objects.  All translations are applied
to the current global matrix.  Thus, a tree of objects
can be defined, each with it's own matrix.  You call the
root object with a viewpoint and whatnot, and the resulting
matrix bubbles down and each object is redrawn with its
transform applied to it's inherited matrix; i.e. the parents
matrix passed down on the matrix stack.

The source comes with a lot of demos, including how to use the
polygon-filled fonts to draw on invisible planes criss-crossing
the screen.  It's fun, easy, and not a big mess like X windows.

Lance Norskog