Re: [stella] entropy & randomness

Subject: Re: [stella] entropy & randomness
From: Chris Wilkson <ecwilkso@xxxxxxx>
Date: Wed, 10 Oct 2001 18:04:36 -0400 (EDT)
On Wed, 10 Oct 2001 urchlay@xxxxxxxxxxxxxxxx wrote:

> Is there anything actually random in Pitfall? The game seems the same
> every time... Pitfall II had what, some sorta hardware random number
> generator? I've got the disassembly of River Raid that was posted here,
> will look when I get home.

Exactly!!!  The whole point of those LFSRs is that they are only quasi-random.
The Pitfall LFSR is sequential not only forwards, but backwards as well.
This enabled David Crane to fit a *huge* map (255 rooms, IIRC) that is always
the same, into just a few bytes.  It's such a beautiful thing.


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