Re: LZ: Line erasing routine


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Re: LZ: Line erasing routine



Min Idzelis wrote:
> 
> I am looking for a routine that only calls FIND_PIXEL once. I would
> write one myself, but i don't actually know how to access the video
> mem directly. Are the memory locations in video mem the actual pixel?


yes.


> For instance, if i add $FF to  FC00 it would make pixel 0,0 black??


OK, if you add $FF to $FC00, you will come up with address $FCFF. 
that's not what you want.  Another thing, the videomem is outputed to
the screen in bytes of 8 pixels.  So say you want to put 1 pixel at 0,0:
you _load_  (I think you confused this with add) %10000000 into the
begining of the videomem ($FC00).  If you want to learn how to access
videomem, I suggest checking out the Nibbles source code, specifically
the drawing of the levels (that's how I figured out all the videomem
stuff).


> Or if i subtract $FF from FC00 would it turn clear? Where is pixel 0,0


No, agian, load %00000000 into $FC00, and that will clear pixel 0,0
(although it wil also clear 1,0 2,0 3,0....8,0, that's the bad part
about working with bytes...)


> and 63,127? Are there any text files about this??
> Thanks for any help.
> 
>      Computers are like drugs: Highly addictive,
> incredibly expensive, and you keep having to buy more
> and better to remain at the same level of amusement.


<pre>
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