Re: [stella] Invaders Demo

Subject: Re: [stella] Invaders Demo
From: Erik Mooney <emooney@xxxxxxxxxxxxxxxx>
Date: Sun, 25 Mar 2001 00:14:09 -0500
>after Erik showed his superb demo, I started playing
>myself with RESPx to get a working Space Invaders
>kernel with 11 evenly spaced enemies. 
>It didn't work with a distance of 9 pixel, so I changed
>it to 12 pixel. This made the kernel a bit more complex
>and it now consumes about 60 bytes of RAM. It's not
>finished yet, but it could be a good start.

Clever thinking, I wouldn't have thought of expanding the spacing to 12
pixels, and I would have thought that that would make the formation too
wide and not have enough space to move laterally, which is a concern in
your demo, although minor, and certainly can't be increased anyway.  You
can also use the full 8-pixel width of the sprites easily now, although
you haven't for all the invaders.  60 bytes of RAM is a bit worrisome, but
all that counts is if everything fits when all is said and done :)

>I can only test this with emulators, it works perfect
>with z26 (not perfect with Stella or PCAE). Now I would
>like to know, how the demo works with a real 2600.
>Could someone please test this for me?

Unfortunately I'm at college and my Atari isn't, as I'd love to see this
run :(

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