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From: jbulf@balsa.Berkeley.EDU (Jeff Bulf)
Subject: Re: detecting double points in bezier curves
Message-ID: <1993Apr19.234409.18303@kpc.com>
Sender: usenet@kpc.com
Reply-To: jbulf@balsa.Berkeley.EDU (Jeff Bulf)
Organization: Kubota Pacific Computers Inc.
References:  <ia522B1w165w@oeinck.waterland.wlink.nl>
Date: Mon, 19 Apr 1993 23:44:09 GMT
Lines: 20

In article <ia522B1w165w@oeinck.waterland.wlink.nl>, ferdinan@oeinck.waterland.wlink.nl (Ferdinand Oeinck) writes:
|> I'm looking for any information on detecting and/or calculating a double
|> point and/or cusp in a bezier curve.
|> 
|> An algorithm, literature reference or mail about this is very appreciated,

There was a very useful article in one of the 1989 issues of
Transactions On Graphics. I believe Maureen Stone was one of
the authors. Sorry not to be more specific. I don't have the
reference here with me.

The article actually was more general than this, giving a way to decide
whether a given (cubic) Bezier curve contains cusps, intersection points
or whatever wierdness. The same treatment is also available in SIGGRAPH 89
course notes for the course called "Math for Siggraph" or something like
that.

-- 
	dr memory
	jbulf@kpc.com
