Physics differences between SuperLemmini and NeoLemmix

[kaywhyn]

I've now added the Bashers & Miners trick to the OP. As far as I'm aware, it's not possible for these skills to mutually cancel each other in NeoLemmix.

You are correct. In the case of the basher and miner, in Neolemmix this means the only possibilities are one gets cancelled but the other continues, or both continue, although the latter is far harder to achieve. Indeed, in NL I think the only skills that can cancel each other out are miners. It's a lot easier to cancel just one miner, but to have both cancel is far harder and much more precise. All other combinations are either one gets cancelled and the other continues or both continue.

I wonder how Icho created the mixed style level in Reunion...? Is it a "super style" which mixes all tiles from all sets? I was thinking of doing the same thing myself, but no need if it already exists!

Yup, the epic tileset is simply all of the original Lemmings and ONML tilesets in one. I remember being in awe seeing the Reunion levels that used the tileset. They're wonderfully designed!

Icho's mixed style is called EPIC. Icho used this style for the final levels of Reunion in each of the 4 ranks

Yikes, you have forgotten that Reunion has 5 ranks

[namida]

I wonder whether the Miner/1px gap trick is also present in Amiga, but I can't think of a suitable level for testing it.

You can set it up yourself in an X-of-everything level. See attached replay (for Gentle 8 of Redux) - the exact setup would be a bit different due to the different builder checks, but same general idea applies. If you were to do this on DOS (and presumably, Amiga - I'd be very surprised if it doesn't happen there too), the miner would cross the gap instead of falling into it.

[WillLem]

Icho's mixed style is called EPIC... So if you have downloaded the Superlemmini 1.43 styles that I posted, you can make levels using this EPIC style for Superlemmini.

I downloaded Reunion (along with music, styles and replays) yesterday evening. I plan on LPing it at some point, it looks like an awesome pack

And yes, it's great to see that the EPIC style is something which already exists!

[Turrican]

Another one:

Load Tame 1 from onml , and try to create a bridge , like the one that is shown at the pictures , that I have attached. How many builders will it take?

It took me 5 builders for the Superlemmini version , and 7 builders for the Neolemmix version. This happens ( if I am correct ) , because of the more relaxed builder checks , the Superlemmini version has , compared to the Neolemmix version.

For Superlemmini , I used the conversion , of the dos version of onml.

[WillLem]

Thanks for the info & screenshots Turrican, I've added this to the OP.

I also confirmed that it only takes 5 Builders in the Amiga version as well, making SuperLemmini consistent with Amiga physics on all points noted so far:





Incidentally, I have noticed that there is at least one way in which SuperLemmini is not consistent with Amiga, and that's with Climbers being able to hoist through a Builder bridge that begins on the very edge of the terrain (the SL screenshot is on the right):



Note that, on Amiga, it is possible for the Climbers to pass the Builders bridge, but in SuperLemmini they fall. I wonder whether this is due to inconsistent Climber-ceiling checks in the Amiga version which Tsyu decided not to emulate.

[WillLem]

I've found another one, but I'm not sure exactly what the difference is here. In the Bonus level "Don't Make The Wrong Choice", NeoLemmix makes it possible for a single Builder to bridge the gap near the end, making a 100% save possible:

NeoLemmix version

However, in the SuperLemmini version, it requires 2 Builders to cross the gap no matter where the first Builder is placed (I've tried!), meaning that it's only possible to save 49/50:

SuperLemmini version

This video shows that the gap requires 2 Builders on the Amiga version as well (the player uses only 1 Builder to traverse a similar gap at the other side of the level, so it's likely they will have attempted the same on this side; the gap at the other side can be traversed with 1 Builder in all versions AFAIK).

I'm aware that LVL-to-NXLV conversion can cause displacements of objects by 1 or 2 pixels, but I'm not sure whether the same happens with terrain.

If so, it could simply be that the level conversion itself has made it possible for a single Builder to bridge the gap, and if not then it could point to another fundamental difference in the physics.

[Turrican]

I've found another one, but I'm not sure exactly what the difference is here. In the Bonus level "Don't Make The Wrong Choice", NeoLemmix makes it possible for a single Builder to bridge the gap near the end, making a 100% save possible:

However, in the SuperLemmini version, it requires 2 Builders to cross the gap no matter where the first Builder is placed (I've tried!), meaning that it's only possible to save 49/50:

The reason for that seems to be a characteristic left-facing builders have in several games/engines. In Superlemmi when a left-facing builder starts building a bridge , it places the first brick , one pixel behind it's feet. That doesn't happen to right-facing builders , and also doesn't happen in Neolemmix in both left-facing and right-facing builders.

The same thing that happens in Superlemmini , happens also in dos. From the "Glitches in Lemmings" thread:

"Right-facing builders place bricks one pixel further in front of them than left-facing builders. This affects the potential length of a bridge that can be made by "stretching" bridges"

I have attached pictures that showcase all these behaviors , by making a climber start building , at the first frame , when it has ended climbing . Pictures are again from Tame 1 from onml ( For Superlemmini , I used again , the conversion of the dos version of onml. )

In the picture you have posted the builder is a left-facing builder , so what I have described here , seems to be the reason for this behavior.

[Simon]

5 builders for the Superlemmini version , and 7 builders for the Neolemmix

This is a particularity of NeoLemmix. I've called this NL's builder belly check, but it's really an extended foot check (up to 3 pixels above ground), or leg check. Besides NL, I don't know any other engine that has a taller foot check than 1 pixel.

-- Simon

[WillLem]

The reason for that seems to be a characteristic left-facing builders have in several games/engines. In Superlemmi when a left-facing builder starts building a bridge , it places the first brick , one pixel behind it's feet. That doesn't happen to right-facing builders , and also doesn't happen in Neolemmix in both left-facing and right-facing builders.

Ah, of course, that old chestnut!

I kind of already knew about this one, but it's good to have it confirmed that it is indeed a physics thing and not just something I was imagining. I even mention it in my SUPERLEMMINGS playthrough; I modified the level to have Builders facing in both directions, because it is slightly more difficult to build to the left (1px more difficult, to be exact!).

I've added this example to the OP, thanks again for confirming.

This is a particularity of NeoLemmix. I've called this NL's builder belly check, but it's really an extended foot check (up to 3 pixels above ground), or leg check. Besides NL, I don't know any other engine that has a taller foot check than 1 pixel.

I wonder what the reason for this is... I'll ask namida on Discord.

[Turrican]

Here is a blocker release technique , that doesn't work the same between Superlemmini and Neolemmix , due to differences in basher physics , between the two engines.

Let's say you have a bridge with a blocker assigned on it , in the position that is shown in the first picture that I have attached.
If you assign an incoming lemming as a basher at the correct position , as shown in the second picture that I have attached , it will release the blocker , but instead of bashing the entire lower part of the bridge , it will just remove some pixels of it ( as shown in the third picture ) , so the bridge won't be destroyed , and the other lemmings will be able to use it.

Now , in Neolemmix what I have described here can work , but only if the bridge is "under construction" ( only if the builder has  has just placed the first bricks of the bridge ) , when the basher is assigned.

If the bridge is complete , or is close to be completed , there is no way for the basher to release the blocker , without destroying the bridge.

[WillLem]

Now , in Neolemmix what I have described here can work , but only if the bridge is "under construction" ( only if the builder has  has just placed the first bricks of the bridge ) , when the basher is assigned.

I'm not quite sure what you mean here. Any chance of a quick video demo?

[Turrican]

I'm not quite sure what you mean here. Any chance of a quick video demo?

In the first 3 pictures , that I have attached , you can see a similar builder-blocker setup , to the one that I used in Superlemmini , but as you can see the builder is currently building the bridge. In that case , you can release the blocker with the basher , without destroying the bridge. ( Same as Superlemmini ).

In the last 3 pictures , we have the exactly same builder-blocker setup , but the bridge is now complete. There is no way now to use this trick now. There no way to release the blocker without destroying the bridge.

[WillLem]

That's an interesting one, Turrican - very likely that it's connected to Basher terrain checks, as per this discussion on how it affects Basher/steel interaction.

Added it to the OP.

[ericderkovits]

ok I figured I would put these on Youtube

Superlemmini ones

1) blocker released by a basher on a bridge(when bridge is complete) basher doesn't destroy bridge (will NOT work in NL)
    https://www.youtube.com/watch?v=iLzcVTd9lUU

2) blocker released by a basher on a bridge(when bridge is still being built) again basher doesn't destroy bridge (Does work in NL)
    https://www.youtube.com/watch?v=mFiVwGtK2c4

Neolemmix ones
1) Attempting to release blocker on bridge by a basher (when bridge is complete) can't release blocker on bridge by a basher when bridge is complete. (Does work in SL.)
    https://www.youtube.com/watch?v=mK46L-7rWgI

2) blocker released by a basher on a bridge (while bridge is still being built). This does work in NL as well as SL.
    https://www.youtube.com/watch?v=gkA2Srl4foU


Thanks Kaywhyn for commenting on youtube. I just wanted to post videos of these 4 so WillLem can see actual videos instead of just pngs.

[kaywhyn]

As I already mentioned on your videos, many thanks for them. It's a lot clearer this way.

Conclusions:

Superlemmini

It's ALWAYS possible to release a blocker on a builder staircase without destroying the bridge so that others can still use it, regardless of whether the bridge is complete or currently in progress

Neolemmix

Two possibilities, either the blocker gets bashed free without destroying the builder staircase, or the blocker gets bashed free but in the process the bridge is destroyed so that others cannot use it.

For the former, this can only happen in the very early stages of the bridge being built. The latter happens if too much of the bridge is already built or is complete.

Grand conclusion: No contradiction in anything Turrican said. To be fair, it was a bit unclear what engines the pictures were for, but based on his description it should be possible to figure out.