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Message: 4417

Author: andrewbroad

Date: 24/08/2004

Subject: Re: JSW64: Manic Miner

 

john_elliott_uk wrote:

>
>> However, it's not a 100% faithful conversion;
>
> Without copying the MM engine wholesale, it can't be.

No indeed! Which is a reason I decided that SPECSAISIE MMtoJSW and
JSWtoMM would modify only data, not code (apart from certain
operands) - otherwise I may as well have gone full circle!

But JSW64 is a completely different matter, since it combines all
the features of JSW and MM, and then some! :-)

> Maximum items: I don't think there is a limit. You might get
> intriguing buffer overflows eventually; rather like what happens if
> you get new lives at a faster rate than you lose them.

Assuming that the number of items collected is represented as a 16-
bit word (since the original JSW engine can represent that you have
collected 256 items - the maximum that will fit in the item-table),
what actually happens on the screen when you have collected more
than 999 items?

>> - 128K tunes (and no attempt to put the red and cyan squares on
>> the correct keys on the piano during the playing of the title-
>> screen tune). I prefer the 48K in-game tune to the 128K
>> conversion that uses only one channel.
>
> If anyone writes a 3-channel version of ITHOTMC, I'll use that
> instead. Or there's 15MOTDMC.

1? 5? M? Of The D? Mountain Cing?

>> - When you complete a cavern, the air empties faster and at a
>> higher pitch than in MM.
>
> Because there's no score.

And thus no incentive to kill the Kong Beast, other than the
satisfaction of seeing it turn yellow and fall upside-down with that
sickly falling noise! ;-)

>> - The JSW item-collection sound. I think it's cool to add this to
>> a MM game, and I might even try to code it up for MM: Allana
>> Truman. But a strictly faithful conversion would suppress it.
>
> Maybe. But I've left it, for the same reason that MirrorMM doesn't
> fix the Block Graphics bug.

Because you don't want to alter the game-engine, at least in a
`negative' way?

MirrorMM and MirrorJSW don't fix the Block-Graphics Bug because it
would entail planting some extra code to do so, my objections to
which are:

(a) my decision to alter only the data, not the code;

(b) since these transformations are required to be strictly
reversible (MirrorMM(MirrorMM(x)) = x in the sense that every byte
is equal to what it was in the original x), it would have to detect
and remove that code, reinstating the BGB - and who's to say the BGB
wasn't already fixed in the original x, as in the latest Geoff Mode?

Sometimes I wish I were Matthew Smith, then I could just reissue the
original Jet Set Willy with the BGB fixed, not to mention the
official Software Projects POKEs, and perhaps tie up the loose ends
(going up from "Watch Tower" and "Rescue Esmerelda"). Only he could
do this with authority - it would be a great sacrilege for anyone
else to do so and claim it to be canon.

>> - The falling Kong Beast is drawn /after/ the portal, instead of
>> falling neatly behind the portal as in MM.
>
> Patch vectors run after the portal code.

Is there any reason why patch-vectors shouldn't run before the
portal code?

>> - In most 48K MM/JSW games, pressing cursor-left/right causes
>> Willy to jump left/right. In JSW128 and JSW64, it causes him to
>> jump straight up.
>
> That's because I have another use for Caps Shift.

Which is?

--
Dr. Andrew Broad
http://www.geocities.com/andrewbroad/
http://www.geocities.com/andrewbroad/spectrum/
http://www.geocities.com/andrewbroad/spectrum/willy/

P.S. I have resumed work on Manic Miner: Allana Truman after a three-
month hiatus due to tennis- and work-distractions. The first 13
rooms are finished; Rooms 13, 14, 16, 17 are partially constructed.

 

 

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