Path: chuka.playstation.co.uk!news
From: alex@teeth.demon.co.uk (Alex Amsel)
Newsgroups: scee.yaroze.programming.3d_graphics
Subject: Re: Light Sources
Date: Mon, 21 Apr 1997 19:37:42 GMT
Organization: Into Beyond
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On Mon, 21 Apr 1997 14:45:12 +0100, Gordon Bell
<gordonb@aisb.ed.ac.uk> did quoth at me:

>Hi all,
>	Okay its time for my first technical question.  From skimming demos and
>the manuals, it looks like the Yaroze system only supports the 3
>parallel light sources, along with ambient light.  In most commercial
>games, there are also spot lights, and point light sources.  I was
>wondering if these are implemented by the professional libraries, or if
>they are hand coded.  If they are implemented in libraries, what are the
>chances of us eventually getting them, or if they are hand written,
>where can I get some information on writing my own.

As far as I know the PS-X only handles 3 sources in hardware. They
take account only of direction and NOT distance. With the full libs
you could probably use matrix calcs etc to do light sourcing in
software, and gs has structures allowing you to set the rgb values on
a per vertex basis, although its internal lighting calcs will then
have no effect.

I'll be playing with this tomorrow :)


* Alex Amsel * Into Beyond Web Design & JAVA Programming *
* http://www.intobeyond.com  *  WWFC Utter Rubbish 1996-7*
MM - "Steve Corica is every bit as good as that Kinkladze"