Re: [stella] bipolar joustpong

Subject: Re: [stella] bipolar joustpong
From: KirkIsrael@xxxxxxxxxxxxx
Date: 7 Sep 2003 03:16:32 -0000
> Thinking on my feet here, if you use a regular playfield, rather than a 
> symmetric playfield, you could use a single byte per playfield row and only 
> use one half of the byte for each side.  For PF0 on the left you don't have 
> to mask anything because the register only uses the left 4 bits, but for 
> PF2 you will need to mask the left half first and then store it.

One thing I'm realizing is I might have more RAM to play with than
I thought.  (Part of that realization comes from reviewing Andrew 
Davie's tutorial forum on Atari Age...I really hope he gets to the 
next lesson which hopefully will finish up with 1-pixel horizontal 

I still have like 100 bytes free, so mabe it would make sense 
to do something along the lines of 1 or 2 bytes per row, rather than 
2 bytes to "describe" the entire playfield of rows with blocks and 
rows with no blocks.  Given how much belt-tightening I'm gonna have to 
do with my kernal...given my simple game concept, RAM and ROM are cheap
compared to kernal time, but that might be true everywhere. (which
is funny, because while a supercharger multiload might give you effectively
more RAM and more ROM, I don't think anything ever gives you more time 
for your kernal.)

> Your playfield bitmap would therefore be only 4 bits wide on either side 
> but you'd be able to have smaller blocks that aren't as tall because you 
> are only using as many bytes as you want rows.  20 rows should be more than 
> enough and yield somewhat square looking blocks.  If you wanted more 
> separation you can force a blank line between rows like Surround.

Yeah, smaller would look better. 
One thing that's surprising me is that so far the best ball 
movment algorithm has been the simple diaganols I have now...
one danger with that and this game is that it might be that 
the ball tends to always go to the same rows...

> There should also be enough CPU time to do some color cycling also ala 
> Warlords.

Hrm.  I'm not sure if I like that or not.  I almost think
that rainbows are a bit of a cliche in atari programming
'cause they're so easy...

Thanks for reminding me to realize that I could take 
advantage of the relatively large amount of RAM space 
I have...
"I tell you, we are here on Earth to fart around, 
 and don't let anybody tell you any different." --Kurt Vonnegut

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