Path: chuka.playstation.co.uk!scea!greg_labrec@interactive.sony.com
From: Sean Kennedy <skennedy@admin.humberc.on.ca>
Newsgroups: scea.yaroze.beginners
Subject: Re: Ordering Tables
Date: Thu, 12 Jun 1997 15:51:10 -0400
Organization: Humber College A.A.T.
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Nelson Santos wrote:
> To whoever can help:
> I am a little unclear as to the meaning of an Ordering Table (OT).
> According to the User Guide, an ordering table is used "for controlling
> the proper display of polygons".  Polygons means 3D, however I've seen
> OT's used in 2D graphics programming as well as a simple "Hello World"
> program.  What gives?

Ordering Tables are another anologous description of the Infamous
Display List.

AutoCAD used Vector Display Lists that were transmitted to the Vector
Display Unit using a serial transfer method in the Olden Days of CAD.
The GCE Vectrex used Ordering Tables to optimize the display list that
the Main Processor had to output to the Display X,Y, Integrators as
quickly as it could.
If a Vectrex {Vector Line Drawing Game Console} had a Dual Processor
system, It could use one Processor for Game Handling, and another for
Vector Drawing. The DATA FORMAT between such a system would use PACKETS.

Now however this Vector Lineto Data/Method set is done to a Raster
buffer [Frame Buffer] array ant the graphics are handled by the VGP unit
in the PSX.
But! The data being transferred and its method is called PACKETS

For Win16/32 people this would be the DrawDeviceContext BitBlockTransfer
Mechanism called     BitBlT()   A very common algorithym used in 2D
FrameBuffer Raster Imaging systems.

> Here is MY analysis:  An ordering table is actually a place where you
> insert a list of instructions on where to place sprites on the screen.
> It basically holds all of the locations of each object on the screen.
> When the list is complete, you call GsDrawOT() to place everything on
> the screen that is defined in the table.

BitBlt()  --> see above...

> Is this correct?  If not, please clarify for me as it seems to be an
> essential step for placing any kind of graphics on the screen.
> Also, how do packets fit into all this?
> Thank you very much in advance!
> Nelson.
I learned the above by circumstance of using a 20Mhz  Microchip PIC RISC
Micro-Controller to overlay a Wind-Direction finder project I got out of
a Popular Electronics Magasine 3-4 Years ago.

-sean