[A83] Re: Mario Side-Scroller

To: assembly-83@lists.ticalc.org
Subject: [A83] Re: Mario Side-Scroller
From: "Dan Weiss" <dwedit@hotmail.com>
Date: Mon, 28 May 2001 15:34:40 -0500
Reply-To: assembly-83@lists.ticalc.org


Not bit level rotation!  The 90° rotation is done by adding 16 (map width) 
to the source offset...


Anyway, the default code does this:
Get (hl)
multiply it by 4
Save it to (de)
add 16 to de
at end, move de back, inc de, djnz, yadda yadda yadda...

Replace it with
loop:
ld a,(hl)
add a,a
add a,a
add a,a
ld (de),a
inc de
cpi ;inc hl, dec bc
jp pe,loop

So it should be like LDIR, but it just adds 8 to everything it copies...

(note, I wrote this in 30 secs, I might have used the wrong parity or messed 
it up by including the cpi...)




>From: Sk8a4good@aol.com
>Reply-To: assembly-83@lists.ticalc.org
>To: assembly-83@lists.ticalc.org
>Subject: [A83] Re: Mario Side-Scroller
>Date: Mon, 28 May 2001 16:10:27 EDT
>
>
>i couldnt find anywhere in the code it transfering the horizontal map to 
>the
>crashman's map.  i didnt see any 'rr' or 'rl's or anything obviously
>multiplying by 8.  where should i remove the rotation?  i couldnt find it
>
>

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