Path: chuka.playstation.co.uk!news
From: Robert Swan <rs108@mdx.ac.uk>
Newsgroups: scee.yaroze.programming.3d_graphics
Subject: Re: What's up with fog?
Date: Mon, 03 Aug 1998 12:08:57 +0100
Organization: I wish!
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Gerrit Goossen wrote:
> 
> Has anyone spent any time figuring out a way to create a "smooth fog"?

Fogging is a bit dodgy, and as (from memory) I dont think you can spread
the fogging out by subdividing a polygon (which makes sense as light
calculations are only carried out once per polygon, regardless of
subdivision and I assume the fogging component of light on a poly is
calculated then). What you can do is mess around with the fogging
attenuation coefficients (dqa and dqb). In the manual it doesn't really
imply that you can mess around with dqb, which affects the 'spread' of
the fogging. This leads onto several points -

1)	make your polygons smaller, so that there are more steps of colours
2)	mess around with dqb (1.25 * 4096 * 4096 is given in manual). Try 1.0
* 4096 * 4096 or 1.5 * 4096 * 4096 (cant remember which one) and you
should find you can smooth out the fogging

Robert Swan
rs108@mdx.ac.uk