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From: session@seq.uncwil.edu (Zack C. Sessions)
Newsgroups: comp.lang.c
Subject: Re: Help w/Plotting a circle...
Message-ID: <1667@seq.uncwil.edu>
Date: 13 Jun 91 16:41:31 GMT
References: <1991Jun11.154335.130@sugaree.uu.net> <8433@awdprime.UUCP>
Organization: Univ. of North Carolina @ Wilmington
Lines: 21

sjb@piobe.austin.ibm.com (Scott J Brickner) writes:

>In general, though, a quick optimization for any of the circle drawing
>algorithms is to only COMPUTE 1/8th of the points, and use reflection
>about the various axes x=0, y=0, y=x, and y= -x for the remainder.

Umm, wouldn't that be compute 1/4 of the points and then use the
reflection method to get the other points? Also, when using the
reflection method to obtain the remaining points, you need to consider
the coordinates of the center of the circle, if it isn't (0,0).
The computation is also elementary trigonometry which I won't go
into since any elememtary book on trig in your library should
be all you need.


Zack C. Sessions
session@seq.uncwil.edu
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