Re: RE: [stella] Space Instigators - Final Version (?)

Subject: Re: RE: [stella] Space Instigators - Final Version (?)
From: Erik Mooney <erik@xxxxxxxxxx>
Date: Thu, 17 Oct 2002 15:22:18 -0400
10/17/2002 2:50:16 PM, Christopher Tumber <christophertumber@xxxxxxxxxx> wrote:

>Erik wrote:
>>I haven't been following the thread much either, but maybe you could take
>>a page from Piero's additions to INV long long ago.  Can you set the player's
>>missile to 4-wide or 8-wide?  Use the player's missile to flicker an explosion in
>>the place of the invader for a few frames when an invader gets hit.
>Umm, I don't think so. On scanlines where Instigators are drawn, I'm lucky if I have 1 cycle available (usually none). 
So this effect would need to be setup at the top of the screen and the explosion would be limited to being a rectangle 
(since I can't change the size/position on the scanlines on which it will be drawn). In addition, the player's shot and the 
Instigator's shot are sharing the ball so it'd have to take into consideration the multiplexing.

That's exactly how Piero did it in INV.  Set it up at the top of the screen; it's just a rectangle;
and it occupies all the scanlines for that row of invaders thus needing no cycles during them.
Display the rectangle in different sizes (flicker between 8-4-2-1 wide) for a few frames and
you have at least some animation for invader-hit.  At the very least, it could look like the
invader shrinks to 1 pixel wide over a few frames.  The multiplexing is the gotcha, but if the
player can't fire again until the very few frames of the explosion are over, it should work.
(And that's how INV did it.)

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