Re: Possibility of "64K only" filecracks?

[BLuRry <brendan.robert@gmail.com>]

On Dec 30 2011, 3:08 am, Steve Nickolas
<lyricalnan...@usotsuki.hoshinet.org> wrote:
> On Fri, 30 Dec 2011, Antoine Vignau wrote:
> > On 30 déc, 06:10, Steve Nickolas <lyricalnan...@usotsuki.hoshinet.org>
> > wrote:
> >> I got to thinking, knowing this has been done for Moon Patrol - and I did
> >> something similar with Alien Addition.  I wonder if it would be possible
> >> to crack other games that need to reload pieces of themselves, such that
> >> they can get those pieces from the LC memory.
>
> >> I...don't really understand how the disk system works very well, and not
> >> enough to actually grovel through a memory dump and see where stuff loads
> >> certain tracks or sectors off the drive.
>
> >> I'm rather curious as to whether it could work for, say, Donkey Kong.
>
> >> -uso.
>
> > Heelllloooooo sir,
> > What is possible with Moon Patrol (load of the moonbase) is not
> > possible with Donkey Kong: half of the disk contains the HGR pictures
> > of the levels (unless you are a very bad player and do not go further
> > than 25m ;-))
> > I don't know for others.
>
> > antoine
>
> Wow, that's daft.  No attempt to compress it into tiles?
>
> LOL ATARI
>
> I once saw a 2-file crack of Lode Runner, though it used the LOL "S" TYPE.
>
> -uso.

Donkey Kong has a lot of empty space and repeating patterns -- I'm
sure that those images could be compressed down a lot smaller don't
you think?  I'm more than happy to donate the compression/
decompression of Apple Game Server 3 for the cause.  The decompressor
was written to decompress a stream of incoming data from a serial
port, but I'm sure that could be very easily translated to something
else.  The compression was written in Java -- and there are conversion
routines to read images from gif/png so you could use screen grabs if
you don't feel like extracting the images directly.  It shouldn't
munge the images with dithering if you use a close-enough palette (I
based the conversion palette off of a YIQ color mapping, so AppleWin
screen grabs that are 560x192 should come back 1:1.)

-B