Aw: Aw: Re: [stella] Brainstorming: Porting Smithereens/Catapult/Stone Sling

Subject: Aw: Aw: Re: [stella] Brainstorming: Porting Smithereens/Catapult/Stone Sling
From: cybergoth@xxxxxxxx
Date: Thu, 24 Jul 2003 13:27:43 +0200 (CEST)
Hi there!

> Manuel wrote:
> > Why a third write to PF1?
> Too many striped PFs and not enough sleep. :-)

Aha! And I thought that was some weird kind of extra-trick of yours ;-)
> > The bottom kernel then does the real work. It's line counter is already
> indexing all data tables and you never have to answer the "to draw or not to
> draw" question - you just always draw.
> Yup (except for the ball).

No. You can easily do a set of ENABL tables for all possible different vertical ball positions as well :-)
> > With a game that simple, you can then buffer all your shape/NUSIZX/HMMX
> data into the RAM.
> > If, lets say the bottom kernel does 10 2LK lines you can buffer all kernel
> data in 2*4*10 = 80 bytes, leaving still almost 50 bytes free...
> That will only save 1 cycle for every read (lda zp,x vs. lda (ind),y). Since
> you are already doing a 2LK, I don't think this will be necessary. Except
> maybe for the castles, though the O2 version uses precalculated graphics
> there too.

Hehe, but what for will you use all the RAM then? And 8 cycles gained can give you a nice buffer for shifting stuff around, plus, the more cycles you save, the more COLUPX writes you can do.

Hm... sounds all doable now... except the "game over" scene. But that can be simplified I think...


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