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From: skinner@saber.UUCP (Robert Skinner)
Newsgroups: net.graphics
Subject: Re: Ray tracing questions
Message-ID: <2036@saber.UUCP>
Date: Mon, 25-Aug-86 16:46:05 EDT
Article-I.D.: saber.2036
Posted: Mon Aug 25 16:46:05 1986
Date-Received: Tue, 26-Aug-86 00:38:33 EDT
References: <386@lll-lcc.UUCP>
Distribution: na
Organization: Saber Technology, San Jose, CA
Lines: 21

> 
> 10.) This question is concerned with the method of antialiasing used by
>      Whitted.  Michael Sweeney, in his master thesis, stated "that the four
>      corners of a pixel are considered to be the same color if the sum
>      of the differences in their red, green and blue components is less
>      than this threshold (the threshold being a value specified by the
>      user)".  Could someone please show me how the sum referred to by Sweeney
>      is derived, given his explanation?

I have seen some of Sweeney's code, the threshold defaults to 40.0 (out of
3*256), but can be specified as a program option.

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Name:	Robert Skinner
Snail:	Saber Technology, 2381 Bering Drive, San Jose, California 95131
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