Path: utzoo!attcan!uunet!snorkelwacker!apple!portal!cup.portal.com!ts
From: ts@cup.portal.com (Tim W Smith)
Newsgroups: comp.sys.mac.games
Subject: Re: anywhere I can get a good LIFE program?
Message-ID: <34516@cup.portal.com>
Date: 4 Oct 90 00:51:15 GMT
References: <1990Oct3.181911.16439@agate.berkeley.edu>
Organization: The Portal System (TM)
Lines: 23

There are two kinds of fast life programs.  The first kind tries to be
fast on a fixed size array.  The other kind tries to be fast on a very
large unspecified array (i.e., it only keeps track of live cells).

What's the fastest anyone has seen for the second class?  I've done
it in O(N log N), where N is the number of live cells, but I'm told
that it can be done in O(N).

If anyone wants to write a life program, I can post some code that
does does the "fixed array via logical operations" method.  It is
implemented for clarity rather than efficiency (although the bit
manipulation is done in assembly), so you will want to tweak it,
but it is a good starting point.  On a Mac II, it can do about
350,000 to 400,000 cells per second.


This might be an example of where graphics that use separate bit
planes for each bit of a colored pixel (e.g. the Amiga?) would be
nice.  By computing each new generation into a new bit plane, you
would not have to lose history information if you wanted to
color code cells.

						Tim Smith