Subject: VRLINK

From: Steve=Cox%model=shop%Mat=[email-masked]
Date: Sat, 13 Aug 94 12:03:22 CDT

A person mentioned Networking Rend386. I would like to also express my
disire to do the same thing ... I have had mixed results running a
Rend386 based game demo over a modem .... 

What I have found out over the last year is two or three techniecs to
network realtime games over either modems/serial or LAN .... a few I have
tryed ... 

Serial/Modem Link : You can basically pip the key strokes from one machine
over to the other and use a case statment to see what remote key was hit,
and then do what ever action is needed.

Problems: This is a start .... but the remote machine will almost immediatly 
get out of sync with the Host .... ( X,Y posistions,heading )

Fix: You can pass a "Token" back and forth between the two machines to keep 
them both rendering at the same speed ... When you use the "Token" techniec 
you can get a VERY good frame rate if both machines are realativlly the same 
speed .... and if not they can stay synced to the slowest machine.

This is the techniec I use and it is "NOT" suitable for "LAN" games since
there is a character being sent over the LAN EVERY frame being rendered ...
let alone 10 people playing !!!!!

A better Techniec :
 There is a better way to code a LAN realtime game and I for one am not 
anywhere near close to getting it done this way ... but here is the way I 
understand it ...

You bascially syncronize your object movement code with the PC's real time 
clock interupt .... by doing this ... ALL the machines playing the game 
are synced together do to the fact that all of them have a real time clock
interupt ... 
You update the objects "coordinant data" ever clock ( or every other or what 
ever)  interupt.... but you don't "RENDER" the objects on the screen right 
away .... this is done in a big WHILE loop or something in the forground .... 
So you basically have every machine cranking out frames as fast as they can 
.... but all networked machines are updating the"object coordinant data" at 
the same time intervals, which makes the fast machines have smooth animation
while the people are moving around .... and the slower machine's having a 
choppy looking frame rate but the same object posistions .... 

This is the way I understand it ... and I have NO code to prove it using 
Rend386 ... One of the problems I was worried about using this techniec
and Rend386 was the fact the Rend mangels the real time clock interupt ....
Now ... this may not be a problem just so long as you can get a steady
timer tick for the coordinant updating. 

I have ALL the code I need for actually sending IPX packets over a LAN
and seeing who is logged in to the same program ... 
What I need is help getting Rend386 syncronized over a LAN/modem/serial
using the above techniec I have explained ... or a variant ...

Does anyone out there have something working that they are willing to
upload ???

Steve Cox
SysOp
Houston Game Designer BBS
(713) 955-8920

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From: Alexander Walsh <[email-masked]>
Date: Mon, 15 Aug 1994 10:59:39 -0230

I'm in ... this is right up my alley (perhaps vr-386 would be a better 
choice for this work as the API is *much* better).

Sandy

----
Mr. Sandy Walsh| I've been coding you, to see what form you'd take. 
[email-masked]| You were hiding in binary, I just wanted to free your shape.
               | - A variant on a tune from "The Tragically Hip"