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Message: 4414

Author: john_elliott_uk

Date: 23/08/2004

Subject: Re: JSW64: Manic Miner

 

In manicminerandjetsetwilly@yahoogroups.com, andrewbroad wrote:

john_elliott_uk wrote:

I've uploaded a release candidate for JSW64: Manic Miner. Unless
anyone finds any bugs in it, I'll declare it final.

What of JSW64 itself and JSW64:Dragon32? Will all three be gamma-
released at the same time?

Probably.

There's a bug in the conversion of MM vertical guardians to JSW64:

- In MM you set the start-sprite and it rotates through the four VG
sprites as you'd expect - hence the animation of different VGs can
be out of phase with each other.

- In JSW, however, the sprite to be displayed cycles constantly from
0 to 7, and is modified before printing by ANDing with the
animation-mask and ORing with the start-sprite. Thus 4-sprite
animations should always have a start-sprite of either 0 or 4.

Hmm. Perhaps if I wrote the start frame into byte 0 of the guardian...

Your conversion is most impressive - particularly the way the items
collected in a room are subtracted and put back when you lose a
life,

That's deliberate.

and the way it handles dropping onto the item under the portal
in "Sixteenth Cavern".

But I think that's a happy accident.

However, it's not a 100% faithful conversion;

Without copying the MM engine wholesale, it can't be.

- Instead of a score, there's an item-count and a global clock.
Since you go back to "Central Cavern" after "The Final Barrier"
with 85 items, what's the maximum number of items you can collect?
And what happens at 1am?

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.

- 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.

- When you complete a cavern, the air empties faster and at a higher
pitch than in MM.

Because there's no score.

- 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.

- The remaining lives animate even with the music off, which I've
always found annoying since I noticed it in JSW128.

Shrug.

- HGs which go left initially start (on the zeroth time-frame) on
Sprite 0 rather than Sprite 3. SPECSAISIE MMtoJSW moves their
start-columns one character to the right.

Wince.

- Eugene's top boundary is one pixel higher than in MM, his bottom
boundary one pixel lower - and he stays at his boundaries for one
time-frame rather than two.

Eugene is now a normal VG rather than a game-engine patch. I'll pull
his boundaries in a bit.

- The quirky feature whereby you can walk through walls at head-
height, jump through overhead wall-blocks, and land on the ledges
on the left of The Wine Cellar is present, unlike in MM.

- The items in "The Vat" and "The Warehouse" have the same PAPER as
background, rather than red and green PAPER respectively.

Engine differences.

- The walls in the Kong-Beast rooms open from top to bottom instead
of from the middle outwards.

Considering how many bytes I had to work with for a generic
opening-wall algorithm, you're lucky it opens at all :-)

- 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.

- Skylabs don't colour the platforms into which they crash.

Code space again. I didn't have room for a copy of the MM
sprite-drawing code, so the Skylabs are drawn as normal JSW guardians.

- Willy faces left above the swordfish at the end.

That's fixable, at least.

- 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.

 

 

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