Path: chuka.playstation.co.uk!scea!greg_labrec@interactive.sony.com
From: Pradip Fatehpuria <pradip_fatehpuria@interactive.sony.com>
Newsgroups: scea.yaroze.programming.2d_graphics
Subject: Re: question about packet
Date: Tue, 26 Aug 1997 14:54:58 -0700
Organization: Sony Computer Entertainment America
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Kin Lee wrote:
> 
> Hi,
>    In the source code of the demo (the one in the red manual):
> 
>    "PACKET CpuPacketArea[2][MAXOBJECT*(20+4)]"
> 
>  Why (20+4) ? Why is it always a multiple of 24 ?
> 
>  Why not "PACKET CpuPacketArea[2][MAXOBJECT*sizeof(some_structure)]" ?
> 
> 
> Kin

Actually 4 bytes is the tag area in the packet and 20 bytes is the size
of the largest possible primitive packet.  So 20+4= 24 bytes per packet.
You may use a smaller value than 20, like (n+4) where n is the size of
the largest possible packet in your models.

To be more accurate, you may calculate the largest possible memory block
taken by all primitives in your world and use that area as the GS packet
area.

Pradip K Fatehpuria