[SUG][PLAYER] Fix misleading traps!

[Proxima]

Namida gave me permission to bump this, because it was wrongly moved to "Closed" despite no fix being made.

I feel disappointed that we couldn't get a consensus on this. I think I'm right in saying that every other time there's been a discussion of misleading game mechanics (fake and invisible, decoration that looks like terrain, etc) we've come down on the side of "don't mislead the player" even if it meant changes that risked breaking existing content.

Maybe an illustration would help, so here's a snapshot from a RockLems level.



The trap is placed so it sits snugly on the terrain -- which with current physics means it's completely harmless. To make it effective, I would have to bury it in the terrain, which is both bad aesthetically and makes it less easily visible -- especially bad with this specific trap as it's long and thin, so even burying it one pixel loses a lot.

Please let's just fix this.

[IchoTolot]

I think the 2 most basic fixes that would most likely not break anything would be:

1.) Expand the trigger areas 1-2 pixels further below.

That would 100% fix cases like the shown crystal trap, or the 10t masher. As objects are placed on the ground there would only be rare cases where level or replay adjustments would be nessesary.

2.) Adjust the trap's graphic 1-2 pixels higher, so that the trigger area stays the same, but the graphic is now in a more fitting place.

This would lead to no replay adjustments being nessesary, but there would be some visual adjustments nessesary on some levels.

[Turrican]

As a middle solution , I think we could keep the existing traps to keep 100 % backwards compatibility with existing levels , and for the problematic traps we could also add versions of them with adjusted graphics as IchoTolot suggests .

Now , I know that's like adding adittional traps in the game , In that case I think we could even make their graphics a little different , to make it clear that's these are not 100 % the same trap .

In that case I think we could handle the issue Proxima showcases , while maintaining 100 % backwards compatibility with existing levels .

[Proxima]

Sorry, but I think that's a really bad idea. We'd gain something for making new levels, but existing levels would continue to mislead. And players would be faced with two different versions of each trap and would have to learn which one has which trigger area.

My preferred fix is simply to move the trigger areas 1 pixel down (2 in a couple of cases). This would only disrupt levels where the trap is, right now, at the exact height where it looks deadly but is safe. In that case, either the designer intended it to be deadly and we'd be fixing the level, or they intended it to be safe even though it looks deadly. I won't be shedding any tears over such designers having to fix their levels.

[Dullstar]

I agree with the suggestion to extend the trigger area. I don't think breaking a few replays is all that bad, and I imagine few if any levels involve such a degree of precision that a small downward expansion of the trigger area would outright break them, and I would not complain about such levels needing to be fixed, nor would I lose any sleep over potentially breaking levels whose solutions rely on the traps looking deadly but actually being safe.

If we fix it by moving the graphic to better match the existing trigger area, while this would guarantee no existing levels are functionally broken, it could make existing content require aesthetic fixes, and there's probably significantly more levels that have the exact trap placement influenced by aesthetics than there are levels that would be broken by a slight downwards extension of the trap trigger area.

[IchoTolot]

My preferred fix is simply to move the trigger areas 1 pixel down (2 in a couple of cases). This would only disrupt levels where the trap is, right now, at the exact height where it looks deadly but is safe. In that case, either the designer intended it to be deadly and we'd be fixing the level, or they intended it to be safe even though it looks deadly. I won't be shedding any tears over such designers having to fix their levels.

That also would catch the cases where the height of the trap trigger area is used to block lems to a certain degree trying to get over it, or trigger area blocks in general.

An extension like in 1.) still has the least impact on the content as a whole while also fixing the problem.

[namida]

I would likely have to do some testing to say for sure, but just from reading and thinking about the descriptions, I find myself agreeing with IchoTolot here - that extending the trigger area is going to be the best way forwards.

That of course doesn't mean it's set in stone as "that or nothing" - let's keep discussing this, we've got a while until a stable release where such a thing could be changed so no super urgency.

With this being said, there is one thing that I am going to set in stone right now. I want this to be the final discussion on changes to trigger areas for the official styles - if the decision is "no change", that's it, case closed permanently. If the decision is "change", this will be the last time they get changed. So whatever we go with - we need to give good consideration to all objects in official styles, not just traps. This doesn't mean the same changes are needed of course - we might decide "exits are fine, but we do need to adjust traps", or "style A's objects are fine but style B's need changes". All I mean here is - once this discussion is wrapped up and any changes coming from it are made, that's it, the trigger areas for the official styles, both in absolute terms and relative to their graphics, are considered finalized.

[ccexplore]

Maybe an illustration would help, so here's a snapshot from a RockLems level.

Is it possible to see a screenshot of this in clear physics mode?  I'm just curious how the trigger areas has been set currently that led to that setup as harmless.  Is it fair to say maybe that particular trap was more problematic than other ones?

[namida]

Maybe an illustration would help, so here's a snapshot from a RockLems level.

Is it possible to see a screenshot of this in clear physics mode?  I'm just curious how the trigger areas has been set currently that led to that setup as harmless.  Is it fair to say maybe that particular trap was more problematic than other ones?

Here's a screenshot of the same objects at the same heights above the terrain, in clear physics mode.

[namida]

Having thought about this, I recall that last time trigger areas were revised for traps (and I believe I applied this to both the official sets, and all Lemmings Plus sets that existed at the time; and further also applied the same rule to teleporters), in most cases it was based on a certain amount above or below where the actual lemming sprite appears in the first animating frame of the graphic.

That particular trap needing to be fairly buried would be very consistent with such an approach. However - to be clear - I'm just explaining here how the current situation arose, and perhaps it is worthwhile to revise this, at least for some traps.

[ccexplore]

It looks like the official Lemmings 1 levels only used that trap once, in Taxing 28 (POOR WEE CREATURES), and it apparently requires burying trap there just as it does in Proxima's example, by the exact same amount in fact.

So I guess the placement of trigger area for that trap just never had been good; seems like it should extend down at least one more pixel to support the rather natural placement shown by Proxima.

(To be precise, this is tested specifically with DOS Lemmings/Lemmix; I don't know about any other ports.)

[Simon]

I still recommend to change the traps as Proxima wants. Interesting that this went under the radar for a year, but it's a physics change and should be well-implemented on first try.

-- Simon

[Proxima]

So I guess the placement of trigger area for that trap just never had been good; seems like it should extend down at least one more pixel to support the rather natural placement shown by Proxima.

(To be precise, this is tested specifically with DOS Lemmings/Lemmix; I don't know about any other ports.)

I happened to discover an instance just now, browsing the old level review topics. On Genesis Sunsoft 9 (Evacuating a coal mine) the trap is in that exact position relative to flat terrain, making it inert on NeoLemmix. But on the actual Genesis version it is indeed deadly.

[ccexplore]

From Gronkling's speedrun attempts on Genesis Lemmings, we've discovered that some objects' trigger areas in that version are apparently slightly different from DOS Lemmings, in some cases not even rectangular apparently (!) but more irregularly shaped.  Not sure though about the details for the specific trap discussed here, it wasn't talked about on that thread (probably because we never gotten on that thread to any levels making use of it?).

Anyway, I agree that the positioning depicted in your screenshot should be deadly, and it's probably worth at least changing that trap to make it so.  That it impacts one of the official levels (even if from specific ports) just makes it more worthwhile to change.

[Proxima]

Okay, time to make a concrete proposal. I have actually changed my mind to some extent after doing some more investigating, and I'm sorry for taking such a belligerent tone with this topic.

I now think that only two trigger areas need changing: the "ghostbuster" trap in the crystal style (which should be moved down 1 pixel), and the rope trap in the pillar style (which should be moved down 2, or maybe 1 -- and maybe also shrunk a bit).

For comparison purposes, the attached level and screenshot show all the traps at the height that would make them only just deadly, under this proposal (i.e. if they were lifted one pixel they would become safe).

Ghostbuster trap: As just mentioned, this affects an official level (Genesis Sunsoft 9). I want to be able to rest the trap snugly on flat terrain, which is especially important as it's long and thin, and burying it one pixel in terrain loses a lot of visibility. The middle portion would then have 2 pixels showing above ground, which is consistent with other traps (see screenshot and further discussion below).

I would prefer to move the trigger area rather than expand it, as it's already 6 pixels tall, and with the trap being so thin, it looks wrong that lemmings can still be killed when moving high over the visible part of the trap.

(No other trap triggers from the official styles are more than 6 pixels in either dimension. In fact, this is the only trap with a trigger area wider than 4, so maybe it should also be shrunk horizontally? If you look closely then it looks a bit weird, because the lemming is suddenly displaced to the centre for the death animation -- but most of the time this isn't something you would notice.)

Rope trap: This also affects an official level (Fun 15 / Taxing 1). On that level, the bottom metal bar is in fact buried 1 pixel, so moving the trigger area down 1 would be enough to make it deadly. However, I'd like to be able to keep the metal bar unburied (which would require moving the trigger area down 2) as this looks better, at least as regards the support structure. However, there is a counter-argument: if you look closely, you can see a ring of darker pixels on the top 4 rows of the dirt mound. This represents the rope that the lemmings have to step on to trigger the trap. If the metal bar is unburied, then the rope is entirely above ground (there is one pixel in between the top of the terrain and the bottom of the rope). So maybe it should be safe at that height (i.e. move the trigger area only down 1?)

For this one, I feel strongly that the trigger area (currently 6 pixels tall) should be moved and not expanded, and maybe even shrunk. As I just said, what kills the lemmings is stepping on the loop of rope -- it should be entirely safe to pass above it.

* * *

For the other traps, I'll explain why I now believe it's best to leave them as they are. I originally proposed that the marble squasher and 10-ton weight also needed adjustment. I've taken a look through the original levels, and noticed that on levels using these traps (e.g. Fun 24 and Taxing 2), the "pressure plate" (the part that the lemming steps on) is partly or completely buried, so these traps shouldn't be causing any problems with original levels. Also, the plate for the marble squasher trap is 3 pixels tall; that for the 10-ton weight is 4 tall. That's enough that if the entire plate is above ground, it looks as if the lemmings are walking past it and it should be safe. So I now think that I made the wrong call here originally -- though since Simon and others supported my original proposal, I wonder what they think about these traps in particular.

So I now suggest that these traps should be left as they are, which means that if the top 2 pixels of the plate are above ground, the lemming will step on it. As I said earlier, that's consistent with the height of the middle part of the "ghostbuster" trap (and also the bottom platform of the wheel).