Re: [stella] More flicker, please

Subject: Re: [stella] More flicker, please
From: Manuel Polik <cybergoth@xxxxxxxx>
Date: Mon, 07 Oct 2002 14:42:06 +0200
Hi Thomas!

>>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.

Well, if an object is at the very right (127) side, it must already have
15 Pixels blanked out. The position where the ANDing must start is at
127-15 = 112, since, as I was trying to explain, I can't move anything
past position 127 (or before pos 0). So I'm gonna lose 15 Pixels on each
side. Standing on position 127 (0) and getting the ship smoothly out of
the screen without losing any width would require shifting of the shape

Or are we talking something totally different here? :-)

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

Please allow up to three days to deliver :-)

>>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. 

Hehe, if I'd understand why, there was no problem to solve :-)

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

Maybe I get it done today, but I fear it'll be wednesday night until I
find some minutes.

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