From: pepke@scri1.scri.fsu.edu (Eric Pepke)
Subject: Re: TECH: Synchronized communications between various machines
Date: 8 Apr 92 14:51:51 GMT
Organization: Florida State University, but I don't speak for them



If I were doing such a thing (and I have done networked games before), I 
would ignore the problem of synchronous communication.  Send object 
updates whenever you can.  You can have a semaphore scheme to make sure 
that there won't be any races, and you can use the same scheme to make a 
batch of updates.  Organize each program as an event loop, updating frames 
as fast as it can based on the current state.  Each time through the event 
loop will look at a system clock to see how much time it's been since the 
last update.  I'm sure that every machine you are likely to want to use 
somewhere has a heartbeat interrupt that would work for this.  Send the 
first and second time derivative along with object position information.  
Use that and the time since last update to interpolate object position 
when the time sampling of position is too coarse.

Eric Pepke                                    INTERNET: pepke@gw.scri.fsu.edu
Supercomputer Computations Research Institute MFENET:   pepke@fsu
Florida State University                      SPAN:     scri::pepke
Tallahassee, FL 32306-4052                    BITNET:   pepke@fsu

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