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Message: 6002
Author: andrewbroad
Date: 22/12/2006
Subject: Re: Start-frames for MM-rooms and (not) for portals in JSW64
Glossary (as used in this message):
/sprite/ An image, possibly animated, that is drawn on the screen,
consisting of a pixel-pattern for each sprite-frame of animation.
/sprite-frame/ One of a sprite's pixel-patterns, used in the context
of animation.
/start-frame/ An initial sprite-frame (typically for Willy - also for
vertical guardians in MM).
Daniel wrote:
>This is true of JSW64 but not MM, as I will explain below.
> There is an interesting phenomenon in "Manic Miner", which could
> perhaps be reflected in the "Advanced MM / JSW Trainer" (AMJT). I
> don't recall it being discussed before, but if it was - please
> forgive me the repetition.
>
> The thing is that the position in which you enter the portal
> (especially by jumping up into it) when completing one room is
> reflected in your starting position in the following room.
> I think that it is possible to design a set of two rooms where youI don't approve of playing-hints in room-names, except in AMJT.
> would fall into an IDS trap in the second room if you don't adopt
> the right position when finishing the first (preceding) room. It
> would be very unfair, of course, but it might be possible to make
> it more fair by giving the player a hint (like the room name: "Face
> Left to be Successful" or something like this :-) ).
I don't approve of infinite-death scenarios, full stop.
I'm trying to think of a non-IDS way to train portal-posture in
AMJT-JSW64, but it's difficult. Maybe falling onto a non-swinging
rope, where you need to fall past it to collect one item, and land on
the rope to collect another - and the only way to do either is to
(re)enter via the portal.
This works (of course it hasn't been tested yet) because collision-
detection for ropes is pixel-based rather than attribute-based, hence
Willy's sprite-frame as well as his cell-column is significant.
> Let me give two examples to illustrate what I mean:This is true of the JSW64 version of Manic Miner, but NOT the
>
> 1. In the original "Manic Miner", if you jump into the portal
> in "The Warehouse" (016) facing left and from the leftmost-possible
> position, you are able to jump over the yellow horizontal guardian
> at the bottom of "Amoebatrons' Revenge" immediately after walking
> left, as it comes towards you. If your position when jumping into
> the portal in "The Warehouse" is not correct, you will not be able
> to perform this manoeuvre in "Amoebatrons' Revenge" and will have
> to wait for a later opportunity to jump over the yellow HG, wasting
> precious time.
original 48K MM!
As explained in my Manic Miner Room-Format
<http://geocities.com/andrewbroad/spectrum/willy/mm_format.html>,
the original MM stores each room's start-position in Offsets 616-622,
with Willy's start-frame in Offset 617 - this overrides whatever
sprite-frame he entered the portal of the previous room with.
JSW (including JSW64), however, has no notion of each room having a
(statically-specified) start-position (it does store a dynamic start-
position whenever you enter a room, to which Willy reverts after
losing a life). JSW has only a /global/ start-position for when you
start the game - this consists of a room-number and cell-coordinates,
but not a start-frame (which is why, whenever you restart a JSW-game,
Willy starts in whatever sprite-frame he finished the last go in).
In JSW64, it's the portal, not the destination-room, that specifies
the start-position. Since each room can have at most one portal, each
room specifies the portal-destination room-number in Offset #F5, the
portal-destination cell-coordinates in Offsets #F6-F7, and the portal-
destination pixel-row in #F8.
But JSW64 doesn't specify a portal-destination /start-frame/, and is
not, therefore, fully faithful to the original 48K MM. You're not
supposed to be able to jump the yellow HG in "Amoebatrons' Revenge"
at the first attempt!
> I think that it would be possible to design a room where you e.g.But that would be an IDS if you got it wrong, would not it? It would
> begin on a conveyor, which carries you towards a Fire-cell and a
> guardian moving towards you (and passing over the Fire-cell), so
> that you have to jump over this guardian on the first opportunity,
> because otherwise you get killed by the Fire-cell (or by the
> guardian itself). You could only perform this manoeuvre
> successfully if your exiting position in the previous room were
> correct.
be grossly unfair to make an IDS conditional on the sprite-frame with
which a player had entered a portal.
--
Dr. Andrew Broad
http://geocities.com/andrewbroad/
http://geocities.com/andrewbroad/spectrum/
http://geocities.com/andrewbroad/spectrum/willy/
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