Re: [stella] single line res

Subject: Re: [stella] single line res
From: Mark De Smet <de-smet@xxxxxxxxxxxxxxx>
Date: Wed, 21 Jun 2000 18:56:25 -0500 (CDT)
> >This is done through VDEL tricks, correct?  From reading the Stella 
> No, VDEL is used for generating double scanline resolution sprites.
> But this is the intended behaviour and not a trick.

> If you want to use double scanline resolution, you would enable VDEL for
> one of the players but not for the other. Then you would update the
> graphics for one player in the even scanlines and for the other player in
> the odd scanlines. This way the graphics would get changed in the same
> scanline for both players. You would loose a bit of resolution, but
> would gain enough enough cycles per scanline to do your display calculations.

I'm not sure I follow that.  The point is to be able to position the
sprites at every scan line, when only updating the graphics register every
other line.  This way if update graphics at the beginning of even lines,
then you would turn on vdel if you wanted the graphics to start on the odd
line.  Turn off vdell if you wan the graphics to start on the even one.


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