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Message: 5784

Author: andrewbroad

Date: 06/04/2006

Subject: Re: Advanced MM/JSW Trainer - Daniel's suggestions

 

Daniel wrote:

>
> I would like to offer some ideas for the "Advanced Trainer" (let
> me refer to it as "AT" for short, not to be confused with "Allana
> Truman" :-) ).

Since the full title is _Advanced MM/JSW Trainer_, if you need an
abbreviation I suggest AMJT.

> I would like to submit a number of ideas, with the hope that they
> may be incorporated into your room ideas (most of them probably
> don't deserve a separate room).
>
>
> 1. Basic jumping - impossible manoeuvres
>
> a) an impossible jump, like for the upper item in "Upper Balcony"
> (032) of "Willy's New Mansion";

Yes.

> b) having to jump /over/ a Water-cell, without landing on it,
> because it becomes a trap, like in "Top of the shop: The Laundry"
> (01) of "Jet Set Willy III" (the Water-cell at [10,14] is a trap -
> I hope I counted correctly).

For this I should introduce a new room: "Traps to avoid" (not to be
confused with Trap-cells!). This would also include the trap at the
top left of "The Bank" [10] of JSW III, and patterns such as:

|..| ||||
|..| |--|
|..| |--|
|||| |--|

|....
|....
|$...
|--..
|....
|--..
|....
|--..
|....
|----

> c) having to jump from far-enough back, because otherwise you hit
> the ceiling, go down and die - like on the lower left-hand side of
> the room "Catacombs" (37) in "Spaceman Willy" (too easy,
> perhaps?).

This belongs in "Jumping left through overhead Earth-cells" [8],
alongside using an overhead Earth-cell to jump off a platform that
is three rows above the platform you land on. Sometimes these Earth-
cells hinder you, sometimes they help.

And there's a less quirky variant where you need to stand far enough
back to hit the side of an Earth-cell rather than the bottom:

.|..|.
......
......
WW....
WW....
--...-
**

> 2. Earth-cells: Jumps through innocent-looking blocks
>
> a) Andrew wrote:
>
> > (...) and Daniel Gromann's overhead ILB.
>
> I feel EXTREMELY flattered to see this feature christened with my
> name :-) . I'm not sure it's appropriate though, because in such
> case a lot of other features should bear the names of people who
> applied them first, why should there be an exception in my case?
> :-) .

Yes, I suppose more of the features should be labelled with details
of the room/game/author of their first occurrence, and of their
first deliberate exploitation.

I suppose the term "overhead ILB" should be sufficient to uniquely
identify this feature, although a Type (2) OEC is also like an
overhead ILB - I think that's why I added your name to it.

> In fact, there are two variants of the OILB, corresponding to the
> two possible jumps through overhead Earth-cells.
>
> The first one is depicted in Andrew's updated document "Quirky
> Features", in point 3 of the section "Jumping left through
> overhead Earth-cells". It sort of corresponds to the jump depicted
> in the same section under number 1a. It can be seen in "JSW: The
> 2005 Megamix" in the rooms "Road to the Inaccessible Castle"
> (071), "Snatch the disk and get out!" (146) and "Shortcut to the
> Roof" (154).
>
> The second variant is even more spectacular, IMHO. It sort of
> corresponds to the jump depicted in the same section under
> number 2, and can be seen in "JSW: Mind Control", in the room
> "The Most Secret of All Places" (112).
>
> BTW, Andrew, perhaps when you update your "Quirky Features"
> document, could you expand it to depict both variants (as points 3
> and 4 of this section, I suppose) ?

No, because your Point 4 works without the leftmost Earth-cell, and
thus reduces to Point 2.

What I will do, when I depict Point 2 in the Trainer, is show the
maximum distance you can fall after jumping through an OEC at this
height.

> b) A "classic" jump through an ILB can also be very spectacular.
> In the room "I used to see the shop from here" (50), DrUnKeN
> mAsTeR!!!'s rendition of "Watch Tower" in the game "DrUnKeN
> mAsTeR!!!", you can jump from the platform hanging in-mid air
> below the conveyor, through the ILB which is the leftmost Earth-
> cell of the ledge on which the uppermost item is sitting. You land
> safely below, and for some reason this jump looks particularly
> spectacular to me :-) .

Yes, the Trainer will show the maximum distance you can fall after
jumping through an ILB. I believe the first use of a maximum-
distance ILB was in MM:Hobbit's "A Thief in the Night" [15]... no
wait, that is one cell-row short of the maximum!

> 3. Ramps
>
> a) There is an extremely interesting design pattern in Sendy's
> game "where's woody", between the rooms "*really rampant rampy
> rope room*" (157) and "decompartmentalization" (158). It's not
> really a quirky feature, I think, but perhaps it would be worth
> presenting (I will certainly reuse it in one of my games).
> Collect the leftmost item in "decompartmentalization" and try to
> get out. Sendy revealed the mystery at the end of the message #
> 5147.

It's essentially just jumping into the foot of a ramp, but it's
obscured by the fact that the Ramp-cells are arranged in a column
rather than a diagonal (not to mention that you're also jumping
through a left room-exit). Here's the pattern in its simplest form:

\.
\=

You cannot simply walk left onto the lower Ramp-cell, because the
upper Ramp-cell intercepts you. But if you jump /into/ the upper
Ramp-cell, you're then standing on the lower Ramp-cell, and can walk
off it to the right (down through '=', which can be any stand-onable
cell).

This pattern does merit an entry on my Quirky Features page - and
inclusion in AMJT - along with simpler cases of jumping into Ramp-
cells (as in The Chapel and Cuckoo's Nest).

> b) Andrew wrote:
>
> > Jumping through ramps: when precisely you can jump through the
> > ramp, and when it catches you.
>
> There is a beautiful design pattern involving this (and a
> conveyor) in the room "Squggle squiggle squigle squiggle" (064)
> in "JSW: Mind Control".

Not really, because the ramp doesn't interact with the conveyor to
any significant extent except to stop you coming down from the top.
It's more a case of jumping off a conveyor into a narrow space
between a Fire-cell and a VG (or falling too far if you overshoot
the mark).

> c) Andrew wrote:
>
> > Effects of \ and / ramps that are horizontally adjacent.
>
> Could you give us an example of a room from an already-existing
> game involving this feature?

Ultimate Manic Miner: "THE COLD ROOM" [27] - see Message 5546.

> 4. Conventional guardians
>
> a) In the room "Whintstanley's crevice" (32) of Lee Tatlock's
> game "Willy vs. the Vampire Lord", when you go for the right item,
> you have to turn round and stand in one character-column in order
> to avoid the fast-moving yellow vertical guardian coming down
> towards you. When you are standing in one character-column,

Not strictly accurate - Willy's rightmost left-facing sprite-frame
is wider than one cell-column in this game! That's why the VG kills
you half the time.

> sometimes the guardian kills you, and sometimes it doesn't,
> depending on where it's facing at the moment it comes down. This
> is a very interesting phenomenon, because it means you practically
> have a random chance of success or failure, unless you are able to
> calculate the guardian movements so that you know when to go for
> the item. I think I couldn't possibly do it myself (calculate,
> that is), but perhaps someone can.

The animation of a VG is separate from its path, so it's quite
possible for one sprite-frame to be showing at a particular point in
its path, and another sprite-frame to be showing the next time it
reaches that point.

This particular VG alternates between its head facing forwards at
its top boundary, and facing backwards the next time it's at its top
boundary (one might therefore call it a 2-phase VG, although I'd be
interested to hear what someone more used to using "phase"
terminology would have to say about that).

Since collision-detection for guardians is pixel-based, the phase of
a VG's animation does matter, and I should try to illustrate this in
AMJT with a more obvious example.

In "Whintstanley's crevice", the player can learn that it is safe to
go for the item after the guardian has faced forwards at the top of
its path (because it kicks out to the left at the bottom), but not
after it has faced backwards (because it kicks out to the right at
the bottom).

A true expert might observe the phase of animation before his/her
first attempt at collecting that item, a good player will learn from
his/her first failed attempt and get it right next time, and a lay
player may be content with random attempts - or just to kamikaze
that item and move on.

The other way to collect that item is to jump into an Earth-cell
(jump right from the very edge of the cell to the left of the hole
at the bottom of the screen), jump straight up, then you can walk
under the VG, grab the item, turn around and escape - but this is
harder than stopping with your back to the wall, as it requires time-
frame-perfect timing as well as the right animation-phase!

> I have a feeling - but I may be wrong - that it's a similar
> situation as with the arrows passing through Kari Krišníková at
> neck-height without collision. Andrew says "if she times it
> correctly", but to me it looks more like blind luck. But again, I
> may be wrong :-) .

There's no such thing as luck in JSW. The game-engine is a discrete
system which is 100% deterministic - there aren't even any
pseudorandom elements.

So it's always possible to solve a problem by pausing the game,
observing the precise positions of the player and the guardians,
(saving a snapshot), trying the required manoeuvre, and (after
reloading the snapshot) trying it again in the next time-frame, or
after walking one step, until you get it right.

It's more chess than luck with this approach, and it's certainly not
blind.

> 5. Arrows
>
> Is it possible to make two arrows collide (going in opposite
> directions)? What will happen?

It would kill you, on the grounds that an arrow collides with any
white-ink pixels that were drawn before the arrow. In the case of
non-white arrows, it would only kill you if the arrow that occurred
first in the guardian-instance list were white.

This feature is not worth including in AMJT, because it's beyond the
player's control - except possibly to impose a time-limit, which is
probably best done by having an arrow shoot a white VG.

> 6. Ropes
>
> Andrew wrote:
>
> > (...) Jumping off a rope onto a stand-onable cell that is as far
> > away as possible (at (6,27) for a standard rope in column 16).
> > Falling off a rope into a 2-column gap that is in the most
> > awkward position (columns 21/22 for a standard rope in column
> > 16).
>
> I would add to it:
>
> a) a very awkward jump from the rope like in the room "Entrance to
> the House" (11) in "JSW: Mind Control" (when you go for the right
> item), involving a quirky jump through an Earth-cell;

Yes.

> b) an awkward jump from the rope, involving a jump through a
> Water-cell (I think it would work with an Earth-cell as well),
> like in the room "Below the Ludicrous Room" (147) in "JSW: The
> 2005 Megamix" (when you go for the right item) or in the room
> "Strange Forestlike Corner" (092) in "Mind Control" (when you get
> down from the rope onto, or rather into, the magenta Water-cells).

Yes. With an Earth-cell, I believe there's only one angle that would
work (two with a Water-cell).

> c) an awkward jump from the rope like in the room "Entrance to
> More Tunnels" (089) in "JSW: Mind Control" (when you go for the
> leftmost item).

Yes - this falls into the category of avoiding Fire-cells as you
jump from a rope.

> d) using the rope to enter an Earth-cell at leg-height
>
> It can be used for various purposes. In the above-mentioned
> room "Strange Forestlike Corner" (092) of "JSW: Mind Control" it
> is used to collect an embedded item.

Yes.

> A few days ago I felt a strong urge to design something, and I
> designed a new room, the screenshot of which I have uploaded to my
> folder in the Files section ("nowa.jpg"). It is *probably* the
> beginning of a new game. It will be a JSW48 game, snapshot-type,

Meaning that you'd have to save a lot of snapshots, rather than
being distributed in SNA or Z80 format?

> very hard, targeted at experts, and it will seek to apply all of
> the known QF within interesting and difficult design patterns (in
> combination with guardian movements limiting the time for
> manoeuvre, etc.). I do not want to give any details of this game
> or time perspective at this point; I will probably just add to it
> slowly whenever I feel a need to try new design patterns, QF or
> other challenges.

Cool! I must confess I've created a lot of MM/JSW files in recent
weeks just to try out design-patterns or JSW64 features, and then
just deleted them - but fear not, the best ones are on my Quirky
Features page and/or will be in AMJT! :-)

> Anyway, on the screenshot you can see a rope, from which you have
> to:
> - jump to the right twice (once through an ILB to collect the
> item, then back onto the rope, and then through the block below
> the ILB to land down safely);
> - after entering the room from above for a second time, you have
> to step down /into/ an Earth-cell at leg-height (to the left), so
> that then you can jump over the gap without hitting the overhead
> Fire-cells.
>
> So that's another example of "using the rope to enter an Earth-
> cell at leg-height".

Perhaps one day we'll have a program to reverse-engineer rooms from
screenshots using AI techniques! ;-) I take it the white 'X' cells
are Earth, the blue 'X' cells are Water, and the red & white 'CI'
cells are Fire?

> e) having to jump for items so that you land on the same rope
> again after collecting them

Yes.

> (too easy, perhaps?);

It can be very tough to do so without losing a life, especially if
Fire-cells are involved (see _Jet Set Willy in Space_: "Sky Hooks"
[48]).

> f) an invisible rope;

Yes. I suppose that's not the only type of invisible challenge that
should be trained! ;-) I've added a new section "Invisible
challenges" to keep all these tricks together, rather than
distributing them amongst the existing sections.

I don't intend to make the invisible challenges very difficult -
just to show the player what sort of tricks (s)he may be up against.

> g) a rope which goes beyond the boundary of the room, like in
> Philip Bee's "JSW (again)", in the room "A Close Call" (22);

Yes. It's certainly interesting how, in this situation, you wrap
around the edges of the screen à la Manic Miner if you stay on the
rope, but if you jump off the rope, you go to the adjacent rooms!

> h) Andrew wrote:
>
> > A rope which collides with other pixels already on the screen
> > and picks you up from wherever you are.
>
> I think that the most spectacular way to present this feature is
> in a room where you actually cannot get onto the rope otherwise,
> like in the room "Ynot?" (43) in James Wyatt's game "JSW meets
> Colossal Cave".

Of course, although that particular room is badly designed because
you have to wait so long for the arrow that most players would turn
back if they didn't know about the arrow.

There are some beautiful rooms - or should I say "splendid
chambers" - in JSWmCC, though. I look forward to playing that game
in RealSpectrum.

> i) The "rope-teleport bug" (recently discussed in messages 5387,
> 5390, 5391 and 5396) - when it is understood correctly and can be
> applied consciously, and if it is something different than the
> above point (h).

I don't yet understand it well enough to induce it at will, let
alone train a lay player to induce it! I'll add it to the list as a
possibility, though.

> 7. Edges of the screen
>
> Andrew wrote:
>
> > Entering a room inside a Fire-cell such that you can escape from
> > it if you move immediately (both variants in the same room).
>
> There is also a third variant: when you enter the room from above
> after jumping through an ILB. An example of this can be seen
> in "JSW: Mind Control", when you enter the room "Playing with
> Yourself" (054) after jumping through an ILB in "A Little Room
> with a View" (021).

It's not really another variant of the feature - it's just having to
move as soon as you enter the room from above, regardless of how you
entered it. So it's an orthogonal combination of two quirky
features, rather than a new one in its own right.

> In fact, I think that feature can also apply to /any/ part of the
> room if you enter it by teleportation and are teleported onto
> Fire-cells. Isn't this correct?

Yes, but it's probably not worth including.

> 8. Items
>
> I think that just for the sake of completion, Andrew, you might
> add an example of "Items on the background cells which are
> collected automatically on entry to the room because of the white
> background INK" (like in the "Swimming Pool" of the original JSW).

It's not worth including in AMJT because it requires no action on
the part of the player other than to enter the room, whereas white-
ink guardians collecting items is a bit more interesting.

> 10. Master Bedroom
>
> I would add a right-conveyor to stop Willy during the toilet-run,
> which will allow him to outmanoeuvre (a) guardian(s), for example
> as in "JSW: The 2005 Megamix".

But walking/falling onto a right-conveyor during the toilet-run
causes Willy to stop and not be able to move! It has the same effect
as holding the right-key while running over Water, except that it's
involuntary and permanent.

I therefore find JSW: The 2005 Megamix to be not toilet-completable,
because you get stuck on a right-conveyor in "^The Wrong Way >The
Right Way" [157].

Bearing in mind what you wrote in Message 5768...

>
> Sorry, I don't understand. How can you stop Willy during the
> toilet-run by holding right (the "Right" key?), if he is already
> moving to the right at double speed? You can only stop him if he
> drops down and you hold the "Left" key before he touches the
> ground.

...I can only suspect that your Spectrum-emulator may not be 100%
accurate, because in both RealSpectrum and on a real Spectrum +2,
you CAN stop by holding right (otherwise I would not have found
Goodnite Luddite to be toilet-completable when I playtested it on my
real Spectrum), and in RealSpectrum at least, you CANNOT move off a
right-conveyor during the toilet-run!

Weird...

> 11. JSW48 Annex
>
> Combined cell-types (same colour-attributes)
>
> I think that a nice example of the application of "Conveyor-Ramp-
> Air" is the room "Towards Your Destiny" (103) in "JSW: Mind
> Control". You cannot walk unless you hold the "Right" and "Jump"
> keys together!

Not to mention ` in RealSpectrum to speed up the emulation,
otherwise it's incredibly tedious! ;-)

> 12. MM48 Annex
>
> a) Andrew wrote:
>
> > A jump over a Fire-cell can cause it to change type, as in
> > MM4's "Dotty"!
>
> Wow, how is this possible?

If you stand just to the right of the 2x2 Fire-cells near the centre
of "Dotty", jump straight up, stand with your legs apart and jump
left over the Fire-cells, then the top-left Fire-cell turns into the
colour-attribute for - and therefore behaves as - Air!

It is indeed specific to MM48 - it doesn't happen in a JSW64:Z
conversion of "Dotty".

But if you edit that Fire-cell's colour-attribute to anything other
than #FF (white INK, white PAPER, BRIGHT on, FLASH on), it doesn't
happen. Weird...

I've got it! It's because Fire has the same colour-attribute as
Crumbly in "Dotty", so by the same logic as you can jump over a Fire-
cell and land *inside* a stand-onable cell, you can get rid of a
Crumbly-Fire block!

In "Dotty" it's a fast-crumbling block because the pixel-pattern is
blank, but in general you might have to jump over a Crumbly-Fire
block up to eight times to remove it.

The first application of Crumbly-Fire that I can think of is having
to relieve items of Crumbly-Fire before they can be collected (best
done with fast-crumbling Fire); the second is to remove Fire-cells
that would block your way later (when jumping up from below or
falling down from above).

Thank you for asking the question that led me to this remarkable
discovery!

> b) Andrew wrote:
>
> > Standing on a Crumbly cell in row 0 causes row 8 to crumble!
>
> I've noticed this amazing phenomenon in one of the rooms of "Manic
> Scribbler".

It first appeared in MM:N-AT's "A Reel Challenge" [1], albeit for
purely aesthetic value. In Manic Scribbler's "Ambergris screen" [2],
it's actually cell-row 9 that crumbles, because the Crumbly cell is
in row 1.

The pixel-pattern crumbles in row 8 (or 9), but the colour-attribute
(and hence cell-type) changes from Crumbly to Air in row 0 (or 1) as
you'd expect.

So the only applications of this feature would be to clear pixels
out of the way of an oncoming guardian, or to create invisible
blocks in row 8 (or 9).

> How can it be explained?

It's because of the way the video-RAM is laid out:

1. The colour-attributes (#5800-5AFF) are mapped exactly as you'd
expect: a sequence of 24 character-rows from top to bottom, where
the colour-attributes in each row are stored from left to right. So
to go down a row, you simply add 32 to the address.

2. The pixels (#4000-57FF) are not stored in such an obvious order.
You have the top third of the screen (rows 0-7 in #4000-47FF),
followed by the middle third (rows 8-15 in #4800-4FFF), followed by
the bottom third (rows 16-23 in #5000-57FF).

But within each third of the screen, you have the top pixel-rows of
each of the 8 character-rows, followed by the second pixel-rows of
each of the 8 character-rows, down to the bottom pixel-rows of each
of the 8 character-rows.

This can be visualised using the following BASIC program (preferably
running at your emulator's maximum speed), which pokes random bytes
to the pixels and then the colour-attributes of the video-RAM:
10 FOR a= 16384 TO 23295
20 POKE a, INT (RND*256)
30 NEXT a

This means that, within each third of the screen, you go down one
character-row by adding 32 to the address, but to go down by just
one pixel-row, you have to add 256 to the address!

So the calculations get complicated when moving from one third of
the screen to another - small wonder that the pixels and colour-
attributes can get out of synch when wrapping from the bottom of the
middle third to the top of the top third!

--
Dr. Andrew Broad
http://geocities.com/andrewbroad/
http://geocities.com/andrewbroad/spectrum/
http://geocities.com/andrewbroad/spectrum/willy/
http://geocities.com/andrewbroad/spectrum/download/trainer.html

 

 

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