Re: A85: FIND_PIXEL


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Re: A85: FIND_PIXEL



Now i remember, in the code for FIND_PIXEL (in the ROM) it has it's
own "ld a,63 / sub c " already in it.  So when using PutSprite, it
actually flips the y coordinates twice.  My mistake.

-mike pearce

On Wed, 20 Aug 1997 09:35:28 -0700, you wrote:

>PutSprite has to do that because it calls FIND_PIXEL when it starts
>out.  Try writing $FF to $FC00.  You'll see that it is in the top left
>corner.  I think the programmers were drunk or something when they wrote
>the FIND_PIXEL routine. <j/k>  Actually, I think they wrote it like they
>did because that is the "correct" way to do it, and it is easier to do
>graphing calculations if you don't have to flip over the coordinate
>system.
>


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