The Direct Drop Topic

[WillLem]

This is really 3 topics rolled into one: Physics research across engines, interpretation across engines, and design of SuperLemmix.

It's inevitable that SuperLemmix would be mentioned, since it's currently the only clone featuring DD as an intended mechanic. That said, I'm trying to keep the topic more generally about DD as a game mechanic rather than necessarily talking about its implementation in SLX.

Reason: In DOS Lemmings 1, the knowledge is that fallers don't exit, splatters don't exit, but fallers-turning-into-splatters may exit during this exact physics update.

It's very likely that all early engines which feature DD do so unintentionally, as a bi-product of incorrectly handled physics. Conversely, the fact that so many of the ports feature DD indicates some possibility of it being intentional in at least one of the ports. Either way, some players may be used to it and - as kaywhyn attests - possibly even look out for it, and regard it as a legit mechanic.

I unfortunately wasn't around for a lot of the early Forum discussion, but I absolutely would have advocated strongly for DD being kept as a "happy accident" that makes the game more playable (IMO). Thankfully, we have an opportunity to open the discussion up again and give it a try. I don't think it will prove to be as problematic as some people theorise.

Those who think it's backroute-prone: can you share one of your own levels that can be backrouted using DD (i.e. without adding extra skills or changing anything about the level)? Also share a replay of the intended solution, if you can*. Thanks.

*To be clear, I'm not going to try and backroute-fix your level as a counter-point, I just want to see some actual examples of what we're dealing with.

[WillLem]

In the meantime, here are some examples of levels for which the DD solution is particularly difficult to execute, especially with Timebombers.

Yes, they're OG levels (not custom levels), but it should at least illustrate how contrived these solutions can sometimes be, using way more skills and techniques than the intended solution requires.

The third of these (Come on over to my place) is the only one which is arguably a "backroute", and is considerably more difficult than many of the other solutions to this level.

[Proxima]

That's a nice 100% direct drop solution to Come on over to my place, but don't forget that DOS only requires... I think it's 80%?

[kaywhyn]

OK, I've added a line to clarify that we're referring to the latest stable version for all clones.

All rightie, thanks. Looks great! Though maybe "unless otherwise noted" would had been better to start it off

That's a nice 100% direct drop solution to Come on over to my place, but don't forget that DOS only requires... I think it's 80%?

Correct, the save requirement for Taxing 22 on Dos is indeed 80%

[Forestidia86]

I unfortunately wasn't around for a lot of the early Forum discussion, but I absolutely would have advocated strongly for DD being kept as a "happy accident" that makes the game more playable (IMO). Thankfully, we have an opportunity to open the discussion up again and give it a try. I don't think it will prove to be as problematic as some people theorise.

What do you mean by more playable? What are the advantages or the potential you see in Direct Drop?

[WillLem]

What do you mean by more playable?

One of the most fun times I've had on the Forums so far is when I took part in this challenge with Minim a few years ago. I also love doing Skills You Can't Live Without with Proxima. A common theme of both of these challenges is to find as many different ways to solve a level as possible. With this in mind, anything that opens the game up for repeated play value and/or increases the chances of finding alternative solutions is an attractive prospect.

Forum content has mostly distilled the game down to "single-solution picture puzzles" - levels that are potentially solvable without even actually playing the game (I even recall someone saying they solved a level using a text editor! )

Whilst I completely understand wanting a level to be solvable only by its intended solution, and I concur that this is a popular level design type for many good reasons, it certainly shouldn't be the only represented example of level design in a community as creative as ours is. There are so many other possibilities that a game like Lemmings can offer (DD being one of them), and I'm up for exploring as many of them as possible.

What are the advantages or the potential you see in Direct Drop?

Great question.

This, for a few examples (I can't vouch for the quality of that pack as I made it a few years ago now!)

The average DD solution takes a certain amount of skill and tenacity to get right, and it's something I feel could make for an interesting and inspiring level design feature: rather than limiting the skillset, give the player plenty of skills but enforce the DD solution. The example above is a full pack of such levels, but the norm could be that a pack might contain a small handful of DD levels dotted throughout to add a bit of spice and variety.

Or, they can be an alternative solution, perhaps. Lemminas Origins features a number of levels for which the talisman is a DD solution: it's solvable in other ways, but finding the DD solution awards the talisman.

That's probably the main advantage I see with it: a DD solution can still be a challenge without necessarily placing other restrictions on the level (such as time, skillset or save requirement). I suppose an eventual goal of mine is to make a non-trivial pack of levels which don't always rely on restrictions to skillset to provide the player with a challenge. DD is just one way to achieve this.

[Simon]

they solved a level using a text editor!

I solved it in my head, then wrote a script to generate an NL replay for it, then verified in NL that the replay was a solution, then submitted the replay and the script.

DOS Lemmings 1

unintentionally, as a bi-product of incorrectly handled physics.
I unfortunately wasn't around for a lot of the early Forum discussion

I'm investigating engine behavior, not classifying it as bug. You started a nice table, and I'd be happy to see more entries filled. I'm criticizing your table for distinguishing the wrong things.



This is from DOS Lemmings 1, and clearly we can enter midair exits. Your table says that we cannot directly drop into midair exits in DOS Lemmings 1. I recommend that you distinguish by activity of the lemming, not by groundedness of the exit nor of the lemming.

It may help you to define direct drop in the first place. You've said "it's basically this" and posted an example gif. Fallers don't exit in DOS L1 even when the exit is grounded, they must start splatting first, yet you say that DOS L1 has direct drop for grounded exits. Floaters enter midair exits, yet you say that DOS L1 has no midair direct drop. What is direct drop?

Do you have an Amiga or emulator ready to run Amiga Lemmings 1? What happens when floaters pass a midair exit on Amiga L1?

-- Simon

[WillLem]

This is from DOS Lemmings 1, and clearly we can enter midair exits. Your table says that we cannot directly drop into midair exits in DOS Lemmings 1. I recommend that you distinguish by activity of the lemming, not by groundedness of the exit nor of the lemming.
...
Floaters enter midair exits, yet you say that DOS L1 has no midair direct drop. What is direct drop?

Direct drop is when a faller or splatter can exit. Floaters don't count, since this costs a skill and therefore can't be relied upon from level to level unless enough Floaters are provided. And nobody, myself included, wants to have to assign Floaters to every lemming just to get a DD or midair exit solution to work.

So, at least for the purposes of this topic, Direct Drop can be defined as contact with the trigger having been made vertically from above, either in midair or from an unsurvivable fall height. Skill action, lem state and any other factors are irrelevant.

"Floatable midair exit" could be its own entry into the table, then, but I've opted not to include that because DD ought to apply to any lemming in order for it to be considered a baseline mechanic. For discussion completion, though:

Do you have an Amiga or emulator ready to run Amiga Lemmings 1? What happens when floaters pass a midair exit on Amiga L1?

Floaters can midair exit on Amiga:

[WillLem]

Updated the OP with a midair exit gif for clarification.

It should be noted that, strictly speaking, {falling into a grounded exit from an unsurvivable height} and {falling into a midair exit} are different mechanics, and can be handled differently by allowing the Splatter, rather than the Faller, to exit (as Simon has rightly noted).

However, since the common theme between them is "trigger contact has been made vertically from above", and ports tend to be consistent about trap / exit triggers in terms of their interactability via DD or in midair, we can use the term "direct drop" to refer to both conditions (at least for the purposes of this discussion).

The compelling factor is contact with the trigger, then, rather than lem state or exit position.

[Simon]

The compelling factor is contact with the trigger, then, rather than lem state or exit position.

Floaters enter the exit trigger from above, too. Anyway, you wrote that floaters are special and we shouldn't care about them here, that's good with me.

You also wrote that you're interested in fallers and splatters only. That's good enough for the research: When a faller can enter without splatting, you get midair direct drop. When a faller-to-splatter or a splatter outright can exit, you get grounded direct drop.

Thanks for showing the Amiga floaters.

-- Simon

[WillLem]

Floaters enter the exit trigger from above, too.

Sure, but if we consider the two questions "did the lemming contact the trigger from above?" and "are they a Floater?", if the answer to the first question is "yes" then we can investigate further for DD regardless of the answer to the second question. In fact, if the answer to the second question is also "yes", then a case can be made for it not being DD at all, at least in the case of grounded exits.

When a faller can enter without splatting, you get midair direct drop. When a faller-to-splatter or a splatter outright can exit, you get grounded direct drop.

Yes, that's a good way of putting it.

Thanks for showing the Amiga floaters.

Very welcome. I find it best to show rather than tell, as much as possible.

[WillLem]

Well, Simon's questions regarding Floaters have turned up something very interesting in the research. Here's a flowchart determining whether an exit action could (or not) potentially be considered as direct drop:

(Green line = yes, red line = no)



The question of whether or not the lemming is a Floater is in fact instrumental in determining whether an exit interaction is direct drop: it's the last thing we check before deciding, and the answer must be "no" DD to be correct.



EDIT: The "midair" question needs to come before the "safe distance" question

EDIT 2: The "midair" question needs to lead straight to the "Floater" question if the answer is "yes"

[Forestidia86]

This, for a few examples (I can't vouch for the quality of that pack as I made it a few years ago now!)

The average DD solution takes a certain amount of skill and tenacity to get right, and it's something I feel could make for an interesting and inspiring level design feature: rather than limiting the skillset, give the player plenty of skills but enforce the DD solution. The example above is a full pack of such levels, but the norm could be that a pack might contain a small handful of DD levels dotted throughout to add a bit of spice and variety.

Acording to the description of the linked level pack you could still make these levels without having DD directly by using certain gadgets. This leaves the decision for designers if they want to allow for DD or not.
Lix has similiar gadgets and even skills that can reset fall height. Having DD might restrict possibilities to create puzzles using these skills.

[WillLem]

Acording to the description of the linked level pack you could still make these levels without having DD directly by using certain gadgets. This leaves the decision for designers if they want to allow for DD or not.

In fairness, if I was going to make a level for which DD was the intended solution, I'd probably use the updrafted exits anyway, because they have a larger and more forgiving trigger area than the regular exits.

Allowing DD as an intended mechanic means that it's always a possibility, not just when the level designer intends it to be. Some people count that as a strong argument against having DD in an engine, whereas I count it as a strong argument in favour of it.

[namida]

Drowning lemmings exactly during transition from falling to drowning. This will be interesting in DOS Lemmings 1: Like faller-to-splatter, it's a transition between two un-exitable activities, and we already know that faller-to-splatter may exit.
Burning lemmings, exactly during transition.

You can't have two different trigger areas on the same pixel in DOS. I suppose theoretically, if you could inject a change exactly between when it checks for each type of trigger area... (maybe by using a debugger and inserting a break inbetween?)