Re: [stella] JoustPong lives!

Subject: Re: [stella] JoustPong lives!
From: Glenn Saunders <mos6507@xxxxxxxxxxx>
Date: Fri, 13 Feb 2004 21:43:29 -0800
At 01:54 PM 2/13/2004, you wrote:
Yes, but it's only relative repositioning, so you don't need a timed
RESPMx, just a write to HMMx and HMOVE. Have a look at Glenn's Death
Derby to get an idea what is possible with missiles (the zombies).

And when you think about the Joustpong kernel vs. the DD kernel, Joustpong is a lot simpler in the sense that:

a) only 2 bits of playfield are dynamic per scanline on the extreme edges of the screen. PF1 and PF2 can be set to blank for the entire screen. Playfield management should be a lot easier.

b) The Joust player are constrained horizontally. Therefore the logic that decides how to draw the sprites can be bunched into the center of the scanline. DD has a very complicated way of branching around to avoid tearing problems that is unnecessary with JP.

c) Joust Pong does have a ball that moves across the entire horizontal whereas DD only has a ball on the scanlines between tombstones. However, it only needs one missile for the Pterry instead of maintaining both for 2 Zombies on DD.

So I'm sure he could do a Pterry.

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