Path: utzoo!attcan!uunet!cs.utexas.edu!sun-barr!apple!well!nagle
From: nagle@well.UUCP (John Nagle)
Newsgroups: comp.graphics
Subject: Re: Tangents to Three Circles
Keywords: Appolonius
Message-ID: <13068@well.UUCP>
Date: 9 Aug 89 16:07:15 GMT
References: <859@mrsvr.UUCP> <BESHERS.89Aug8163857@cs.cs.columbia.edu> <4630@eos.UUCP>
Reply-To: nagle@well.UUCP (John Nagle)
Lines: 11


      In classical geometry, this is called the Problem of Appolonius.  
There is a compass-and-straightedge solution to this problem, not that
many people care any more.

      AutoCAD has a solution to this problem built into it.  The solution
used in AutoCAD was new, and had good numerical stability without special
casing.  It was developed by Autodesk's staff topologist, and, as far as I 
know, has not been published.  

					John Nagle