Re: [stella] Trick12

Subject: Re: [stella] Trick12
From: "Eckhard Stolberg" <Eckhard_Stolberg@xxxxxx>
Date: Wed, 14 Mar 2001 20:45:34 +0100
> Wow.. that code is eerily similar to mine.  Although I put mine at the top
> of RAM and you put yours at the bottom. :)  My code is able to do a
> load/store for missiles, although I'm not quite sure how to make that
> useful... I posted my source, have a look.

Missiles might not be too useful anyway, since they are always set to
display two copies like the players. But you could use the ball instead.
That would at least allow one shot per invader row without flickering.
You might have to limit the invader shots to come only from the last
row of invaders though.

> I replace my stores with stores to a RAM address fine... I'm not sure what
> you mean.

I think you are right. MAybe I'm thinking of some other problem in
my code, that I was blaming on the trick, as I wasn't fully understanding

> Your invaders are all ugly blobs, mine are much better :)  I've also got
> single-pixel precision for the positioning, although yours replicates the
> way the original moves one row at a time rather than the entire formation.

Ha, my mighty invaders will eat your tiny little kindergarten-invaders
for breakfast. ;-) But hey, I just realized that, if I changed my sprites
to six pixels width too, I could shift the last two invaders per row, and
display 11 evenly spaced invaders that way. But since the two pixel
shifting happens to other sprites too, when you remove some from the
formation, this might not work in all situations. Might be worth a try

Ciao, Eckhard Stolberg

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