Path: utzoo!attcan!uunet!peregrine!elroy!ames!nrl-cmf!mailrus!uflorida!gatech!mcnc!thorin!tyler!brown
From: brown@tyler.cs.unc.edu (Lurch)
Newsgroups: comp.graphics
Subject: Re: raytracing in ||
Keywords: 4 rays per pixel
Message-ID: <5548@thorin.cs.unc.edu>
Date: 28 Nov 88 22:29:06 GMT
References: <9700001@datacube> <3148@uoregon.uoregon.edu> <1351@umbc3.UMD.EDU> <5263@cbmvax.UUCP>
Sender: news@thorin.cs.unc.edu
Reply-To: brown@tyler.UUCP (Lurch)
Organization: Chess Pieces 'R' Us
Lines: 22

In article <5263@cbmvax.UUCP> steveb@cbmvax.UUCP (Steve Beats) writes:
>In article <1351@umbc3.UMD.EDU> bodarky@umbc3.UMD.EDU (Scott Bodarky) writes:
>>
>>[stuff about transputer raytracing deleted]
>>
>If you sample the scene using one pixel per ray, you will get
>pretty severe aliasing at high contrast boundaries.  One trick is to sample
>at twice the vertical and horizontal resolution (yielding 4 rays per pixel)
>and average the resultant intensities.  This is a pretty effective method
>of anti-aliasing.

From what I understand, the way to achieve 4 rays per pixel is to sample at
vertical resolution +1, horizontal resolution +1, and treat each ray as a
'corner' of each pixel, and average those values.  This is super cheap compared
to sampling at twice vertical and horizontal.

>	Steve

Randy 'no raytracing guru' Brown

----
Back off, man!  I'm a scientist!       brown@cs.unc.edu   uunet!mcnc!unc!brown