Path: chuka.playstation.co.uk!news
From: "Craig Graham" <c_graham@hinge.mistral.co.uk>
Newsgroups: scea.yaroze.programming.3d_graphics
Subject: Re: Lighting
Date: 13 Jul 1998 22:03:40 GMT
Organization: PlayStation Net Yaroze (SCEE)
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References: <6odou2$ajq2@scea>
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Steve Spiller <steve@microdot.com> wrote in article <6odou2$ajq2@scea>...
> Is there a way to create/simulate point or spotlight lights?  Looking
> through the library docs it appears you can only have ambient or parallel
> lighting...

Do a manhattan distance on the unified vertex coords (final transformed),
then if the distance is within your point lighting radius you can either:
1) Modify the RGB graduated shade texture poly primitive RGB values
    to overlay the lighting (good for static wall lights - do it once and
the light
   is always there when you display the model).
2) Create a transparent gourard copy of the poly's within the lighting
radius
   and sort it into the OT before the model you're lighting (it'll overlay
it giving
   the impression of a light). Looks better than method one, but increases
the
   polygon count.


> -Steve

I know that sounds pretty complex - but it's worth the effort believe
me....

Craig.