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From: jdb@reef.cis.ufl.edu (Brian K. W. Hook)
Newsgroups: comp.lang.c
Subject: Efficient algorithm needed
Message-ID: <27497@uflorida.cis.ufl.EDU>
Date: 18 Mar 91 13:40:07 GMT
References: <2538@odin.cs.hw.ac.uk> <4987@goanna.cs.rmit.oz.au>
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I am working on a Windows 3.0 version of XEYES and need a very fast and not
necessarily accurate algorithm for determining the following:

Given an ellipse and a point, determine where a line from the center of the
ellipse to the point will intersect the ellipse.

You are give:

The center of the ellipse
The width of ellipse
The height of the ellipse
The X and Y coordinate of the point

I need efficiency mostly, since I will be running this on Windows (which is
strapped for resources as is) and I am doing this calculation 10 times per
second.

Brian

PS Please email replies if possible.