Path: chuka.playstation.co.uk!scea!peter_alau@playstation.sony.com
From: Kirk Bender <kbender@znet.com>
Newsgroups: scee.yaroze.programming.3d_graphics
Subject: Re: Looking for...
Date: Mon, 04 Jan 1999 21:53:30 -0800
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Harvey Cotton wrote:
> 
> Robert Ruza wrote:

> > And could someone give me a functioning 3d Sprite Routine, or post it
> > here? Yes, I saw the old messages, but I would like to get it in one
> > piece, that would be more than nice....8-D

> Heres a function to draw a 3d sprite:
>
 
thanks.  I'm curious about--

>                 sprite.scalex=sprite.scaley=16777216/transformedPosition.vz;

Where does the 16777216  value come from?  I use
sprite.scalex=sprite.scaley=ONE*projectionDistance/transformedPosition.vz;
where ONE=4096 (from libps.h)

GsSortSprite(&sprite,&OTable_Header[CurrentBuffer],transformedPosition.vz>>(precision-2));

What is "precision" (I assume it's the number of bits of the ot size?)
and why do you subtract 2?
Mine works, I it's just that I found the right value by trial and error.

cheers,
kirk

-- 
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Kirk Bender kbender@znet.com http://sj.znet.com/~kbender
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