Path: chuka.playstation.co.uk!scea!greg_labrec@interactive.sony.com
From: Ed Federmeyer <fedeedw@charlie.cns.iit.edu>
Newsgroups: scea.yaroze.programming.3d_graphics
Subject: Re: Z-sorting really means *Z* sorting!
Date: Mon, 21 Jul 1997 23:25:50 -0500
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Developer Support wrote:
> 
> Jamin Frederick wrote:
> >
> > Could you go into a little more detail on how to do this?  How do you
> > stick another OT into the normal OT, and what do you choose for the
> > size of the extra OT?  I'm familiar with the idea, I just haven't seen
> > any examples...
> >
> > Jamin
> 
> Just setup a completly new OT and call GsDrawOT twice, the first one
> will then be drawn before the second. Just remember to use GsSortClear
> only on the first OT, otherwise the second clear will wipeout the all
> thats been drawn in the first OT.
> 
> Stuart

I actually created a second OT, and then used GsSortOt(), to "sort" the
little
OT into the WorldOT, just as if it was any-old sprite or line or
whatever.

I also just used the same "PACKET GpuOutputPacket" struct in the new
OT.  It seems
that the PACKET data struct keeps track of it's internals, and you can
point
any number of OTs at it.  (Correct me if I'm wrong!  Works great so far
though!  :-)

This is kind of nice, because then you treat all objects in the code the
same.
(ie, Sort them into the WorldOT, and let the GsDrawOt() figure it all
out.)
But I can see the seperate drawing of two OT's as coming in handy as
well.

The first time, I made my new OT_LENGTH much smaller than the WorldOT,
but it
didn't work.  I then changed it so that the OT_LENGTH of the "little" OT
was
the same (12) as my WorldOT.  It worked then.  I have a feeling though,
I just
forgot to update the "shift" parameter of my GsSortObject4() call to
draw
the little .TMD object into the little OT, and that I could probably get
away
with a much smaller "small" OT.

Ed Federmeyer