Path: chuka.playstation.co.uk!scea!greg_labrec@interactive.sony.com
From: Elliott Lee <tenchi@netmagic.net>
Newsgroups: scee.yaroze.programming.2d_graphics
Subject: Re: bright sprite, I dont want a fight, not tonight, I just want to get it right, can someone shed some light ?
Date: Mon, 23 Mar 1998 15:46:31 -0800
Organization: Cisco Systems
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Message-ID: <3516F457.59F2FCEE@netmagic.net>
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Craig Graham wrote:
	[...]
> A "Sprite" isn't a sprite in the way you're thinking of it at all.
> When you call GsSortSprite() it puts the equivalent of MoveImage()
> instruction into the GPU packet buffer (and a ref to it in the OT).
> Once the instruction is generated
> anything you do the the GsSPRITE struture will have no impact on
> the "sprite" that gets displayed - because it's not really a sprite
> (a true sprite is an independant entity overlayed on the video plane
> by the hardware, which is what's confusing you here).
	[...]
> Craig.
	[...]

Yup, that's right on the spot.  The GsSPRITE structure is like a
template for the data and the GsSort*() routines allocate a copy
of that structure in your ordering table.

If you plan to change RGB values a lot, what you might want to do is
create a function wrapper around GsSortSprite()/GsSortFastSprite()
e.g. AddMySprite(ordertbl,sprite,r,g,b)) to add a thin layer of
abstraction.  That way you just call AddMySprite() with your RGB
values and it will adjust the GsSPRITE members and add the sprite
to the proper ordering table...

- e!
  tenchi@netmagic.net
  http://www.netmagic.net/~tenchi/yaroze/