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From: jrl%images1.waterloo.ncr.com@RELAY.CS.NET
Newsgroups: comp.sys.handhelds
Subject: RE: <None>
Message-ID: <02EA16876DFF002164@gacvx2.gac.edu>
Date: 16 Nov 90 21:57:41 GMT
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In article <0471181703FF001A65@gacvx2.gac.edu> you write:
..
>          i) I find moving the sprite to the left is quite difficult
>             since there is no equivalent instruction to Vx=Vx-KK only
>             Vx=Vx+KK. Am I missing something fundamental? Does anyone have
>             a nice little routine or algorhythm (spelling?) to explain
>             a simple way to do it.
..

I haven't played with CHIP so I don't know whether this will apply,
but...

I'm thinking of Vx as position, not velocity. Is that correct?

If it's position then a move of KK to the left on a display can also be
taken as a move to the right by an amount that is KK unit smaller than
the width of the screen.  With that in mind Vx=Vx-kk can be taken as
Vx=Vx+(width-kk).

-- 
john.Latala@Waterloo.NCR.COM