Re: [stella] More flicker, please

Subject: Re: [stella] More flicker, please
From: Thomas Jentzsch <tjentzsch@xxxxxx>
Date: Mon, 07 Oct 2002 14:05:48 +0200
Manuel wrote:

>The stuff my engine can display is allowed to have 128
>different horizontal positions.
>It's a miracle that this is working at all and that I managed
>to get these centered.
>Expanding that system to both sides for another 15 Pixel would
>certainly break the repositioning code. Plus it'd complicate
>other game / kernel inside logic a lot, because all is set up, 
>planned and prepared for 128 Pixels width, even the radar.

Hm, but partially visible objects would not cause you to 
increase that size. 
If an object is on the very right side (e.g. at pixel 127), 
part of the left half is ANDed out or hidden behind a PF mask 
that starts at pixel 128 (+left border). And the right half is 
completely disabled.
If it is on the very left side (e.g. a bit below pixel 0), than   
the left half is disabled and the right half is masked.

>Or am I not getting yet another thing? We're
>still just ANDing, not RORing, right? :-)


>Ok, I'll do my best :-)

Waiting... :-)

>Just I don't get a smooth transition done
>between  the point where still the half sprite is done and
>where finally the kernel kicks in. Any object starting at a
>certain range inbetween these two points get's invisible. So
>there's a blind spot for any ship of any size. That's what I
>meant, I hope this time I'm making myself more clear.

Yes, perfectly. But I still do not understand why. Many 2600 
games have proven that this shouldn't be such a big problem. 

I guess, I'll wait to see your commented code...

Have fun!	

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