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Re: Fast-wipe Hires

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On Friday, August 31, 2012 2:10:07 PM UTC-5, Antoine Vignau wrote:
> Even faster ;-)
> 
> - divide your lookup table into two tables: one for low @ and one for high @
> 
> 
> 
> lookupl hex D050D050D050 ...
> 
> lookuph hex 232322222121 ...
> 
> 
> 
>  LDY #24-1
> 
>  CLC
> 
> clearloop
> 
>  LDA lookuph,y
> 
>  ...
> 
> 
> 
>  LDX #40-1 (and not 40)
> 
>  LDA lookupl,y
> 
>  ...
> 
> 
> 
> You'll save one DEY per loop and even more with #40-1 instead of #40 :-)
> 
> 
> 
> antoine

That's good feedback!  Thanks Antoine!  I expanded this out to EOR page 1 and page 2 and flip on the VBL.  This proof of concept has shown me that the resolution of the display does not seem so low when you're flipping pages rapidly to produce optical illusions.

I've been able to reproduce these two:

http://www.moillusions.com/2007/01/flying-through-city-stereogram.html
http://www.grand-illusions.com/opticalillusions/chris_walken/

And I also have a take on this one which makes it look like it's continually expanding:

http://www.moillusions.com/wp-content/uploads/img142.imageshack.us/img142/4364/bulge023qx.gif

All in all, the speed of the routine is key to reversing the screen quickly.

More to follow...

-B

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Re: Fast-wipe Hires Antoine Vignau <antoine.vignau@laposte.net> - 2012-08-31 12:10 -0700
  Re: Fast-wipe Hires BLuRry <brendan.robert@gmail.com> - 2012-08-31 15:55 -0700
    Re: Fast-wipe Hires BLuRry <brendan.robert@gmail.com> - 2012-08-31 17:49 -0700
      Re: Fast-wipe Hires Antoine Vignau <antoine.vignau@laposte.net> - 2012-08-31 22:25 -0700
        Re: Fast-wipe Hires BLuRry <brendan.robert@gmail.com> - 2012-09-01 15:55 -0700

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