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From: mccaugh@s.cs.uiuc.edu
Newsgroups: comp.graphics
Subject: Re: Circle Through 3 Points
Message-ID: <207400009@s.cs.uiuc.edu>
Date: 10 Aug 89 17:25:00 GMT
References: <207400008@s.cs.uiuc.edu>
Lines: 8
Nf-ID: #R:s.cs.uiuc.edu:207400008:s.cs.uiuc.edu:207400009:000:471
Nf-From: s.cs.uiuc.edu!mccaugh    Aug 10 12:25:00 1989


 More should be said about point 3 (all points being collinear (co-linear?)):

 Even when m1 <> m2, if these two slopes are "very close" a "very large" radius
 is called for, which may force the circle's center (s,t) outside the viewing
 area. For that matter, overflow can occur in the divisions of succeeding steps
 computing s and t. Therefore, it is prudent to check for m1 "close to" m2 as
 well as for equality, though "closeness" is relative to the user's system.