Path: chuka.playstation.co.uk!news
From: Chris Chadwick <xjk18@dial.pipex.com>
Newsgroups: scee.yaroze.programming.2d_graphics
Subject: Re: Sprite Z Ordering
Date: Tue, 22 Apr 1997 03:54:33 -0700
Organization: PlayStation Net Yaroze (SCEE)
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Hi Lo,

SCEE Developer Support wrote: 
> The values for the size of the PACKET arrays are partly
> arbitrary; basically, every primitive requires up to
> 24 PACKETS; and the PACKET scratchpad must be enough
> for all the primitives we want to draw. Given we don't want to
> have to calculate the exact number each time, we just set
> an upper limit, hence you may often see sample code
> like this
> 
> #define PACKET_MAX1 24    // max number of packets per primitive
> #define PACKET_MAX2 2048  // max number of primitives we want to draw
> 
> PACKET GpuPacketArea[2][PACKET_MAX1 * PACKET_MAX2];

What actual information is contained in the 24 PACKETS(bytes) of each sprite primitive?
I *had* thought it might comprise a copy of the GsSPRITE object registered in the 
OT with GsSortFastSprite(), plus a pointer to the next primitive in line but, by my calculation,
all the members of a GsSPRITE object add up to 22 bytes, leaving only 2 bytes for the pointer!

Also, why are GsOT_TAGS defined as two bit-fields (unsigned p:24 and unsigned char num:8)?
I thought just a normal (32bit) pointer would be used - although I suspect this has something to
do with the three CPU logical address spaces used to map the 2MB of physical memory (maybe!?).

Sorry, but I had never heard of Ordering Tables until I got my Yaroze (there, I've admitted it :)
All the details please someone!

	Cheers

		Chris