Xref: utzoo comp.graphics:1820 comp.sys.ibm.pc:12495
Path: utzoo!mnetor!uunet!mcrware!jejones
From: jejones@mcrware.UUCP (James Jones)
Newsgroups: comp.graphics,comp.sys.ibm.pc
Subject: Re: COMPLICATED PROBLEM; ONLY INTELLIGENT PEOPLE SHOULD READ
Message-ID: <608@mcrware.UUCP>
Date: 27 Feb 88 10:58:17 GMT
References: <971@ut-emx.UUCP> <5569@cit-vax.Caltech.Edu>
Organization: Microware Systems Corp., Des Moines, Ia.
Lines: 16
Summary: Jordan theorem caveat

I've seen several responses to the query that state a method based on
the Jordan theorem--since the original poster didn't give details of the
figure, it probably merits pointing out the hypothesis of said theorem
requires that the curve in question be a simple closed curve, i.e. it
can't cross itself. 

(If you allow crossings, then consider a figure eight.  There are a
whole lot of points people would normally consider to be on the
"outside" from which one can draw a ray that hits the figure eight right
where the top and bottom halves touch.  One might be able to work around
this by saying "well, that counts as two intersections--consider the
number of times you cross the ray if you draw the figure eight with a
pencil."  It could get tricky, though, e.g. if the line segments the
original poster said he was starting with end at a crossover point.)

		James Jones