Re: particle cannons (was Re: [stella] More flicker, please)

Subject: Re: particle cannons (was Re: [stella] More flicker, please)
From: Christopher Tumber <christophertumber@xxxxxxxxxx>
Date: Tue, 08 Oct 2002 14:38:15 -0400
>It's just too much to do during too few cycles.
>I'd preload two RAM bytes and would need to rotate them 
>every nth. line towards the center of the screen, within 
>a certain range. Then I'd blank it in the middle section 
>and on the bottom of the screen, I'd rotate it back 
>within a certain range. That alone is killing the idea, 
>even without the extra check for the crosshair in the 
>middle :-)

Any reason (besides elegance or ROM space) not to split your display kernal into three parts? Part 1 would display the top half of the screen, part 2 would display the crosshair's scanline only (and enemy ships). Part 3 would display the lower half of the screen.

Part 1 and part 3 are essentially duplicates of each other, part 2 just ignores the whole missile controversy and only displays the crosshairs plus any enemy ships. This should free up a bunch of cycles on crosshair scanline. Because the shots terminate at the horizon, so shots in the upper half the screen never go into the lower half and the shots in the lower half of the screen never proceed into the top half you could treat the upper and lower halves of the screen as completely seperate entities as far as the missiles go...

This would make later changes to the kernal more difficult since you have to change all three parts but...

(but I'm not the one who has to implement it!)

>Then the stars would pulse too.

Well, if you split your kernal as above, you could just push new values into COLUPF only on that one scanline...

>No, all feedback is good feedback. I always try and 
>think about everything people are suggesting.

<Smile> Gonna hold you to that....


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