Path: utzoo!utgpu!watmath!att!tut.cis.ohio-state.edu!cs.utexas.edu!uunet!cbmvax!daveh
From: daveh@cbmvax.UUCP (Dave Haynie)
Newsgroups: comp.sys.atari.st
Subject: Re: Multitasking on the ST
Message-ID: <7658@cbmvax.UUCP>
Date: 14 Aug 89 20:50:12 GMT
References: <29201@pbhya.PacBell.COM>
Organization: Commodore Technology, West Chester, PA
Lines: 43

in article <29201@pbhya.PacBell.COM>, dbsuther@PacBell.COM (Daniel B. Suthers) says:

> After reading this a question popped into my head.  If you are downloading in
> the back ground (it seems the most popular multi-task task) and running a 
> action game in the foreground,  do you set the download process to the 
> highest priority to avoid losing data or do you just put up with longer
> download times and connect times so your joy-stick will be responsive?

Assuming your connection won't time out on you, and all your actual byte 
grabbing is interrupt or DMA driven (as on the Amiga), it's pretty much a matter
of personal choice.  Or looking at it another way, at least when talking to a
commercial network, you'll pay for a higher game score with longer connect
times.  

It's probably not that simple, though.  In many video games, the game itself
is taking most of the CPU time, at least on a 68000 processor.  So if your
video game is at a priority higher than that of your download, you may starve
the XMODEM or Kermit protocol program.  To be safe, I'd keep the download at
the same or greater priority than that of the game.  Though on 68020 or 68030
Amigas, you rarely run into that kind of process starvation.

> While I'm at it...
> What is a "ray trace" that most amiga users seem to want to generate them, and
> are willing to wait 2 or 3 days for the output???  The ray traces I've done
> have always completed over-night, and that's longer than I wish to wait for
> a pretty drawing.

Lots of Amiga folks are doing pretty serious ray tracing.  Part of the limits of
what you're going to be tracing are based on what you have available to enter
the image in the first place.  Tools on the Amiga like Byte-by-Byte's Sculpt-
Animate 4D allow some pretty serious drawings to be entered.  It's not only
a timing issue, either -- I have two friend heavily into ray tracing.  One is
currently hitting memory limits on a 17 megabyte system I've set up here at
Commodore, the other already has some images that can't be rendered on a 25
megabyte system.  These certainly aren't typical users, but even for smaller
ray traces, what finishes in 20 minutes on a 68030 system might take 25-100
times longer on a 68000 system.

> Dan Suthers, Analyst, Pacific Bell
-- 
Dave Haynie Commodore-Amiga (Systems Engineering) "The Crew That Never Rests"
   {uunet|pyramid|rutgers}!cbmvax!daveh      PLINK: D-DAVE H     BIX: hazy
           Be careful what you wish for -- you just might get it