It appears to have been triggered by the form resizing. Your instincts are likely correct: if the resolution change occurs on wake, that could trigger a form resize.

Not sure exactly why the exception occurred though. Maybe more resolution-specific guards need to be in place.

Good to know that no data was lost, that's fortunate.

The buttons now work.

The list is pretty much done. Adding/removing/selecting pieces syncs perfectly between level and list. It's necessary to manually refresh the list (by simply re-focusing the window) after making changes to the level, but this is acceptable. It would be better to have action-by-action updates, but my attempts to implement this resulted in messy circular logic, so I decided to refresh on focus instead. Let's see how we get on with that.

Preview

Implemented in SLXEditor commit 3772915.

Taken the first step with the "Pieces List". So far, we have 2 list views for each of Terrain and Objects. This lists the pieces by index, and shows the name, type and draw mode. Here's a preview:

Pieces List Preview

As shown in the screenshot, it's possible to select a piece in the list and have it select that piece in the level arranger (multi-select is also possible). The buttons on the right don't do anything yet, but that's probably the next step.

I'll report here once more has been done.

Quote from: Proxima on April 04, 2026, 04:46:47 PMI am completely against changing levels just to make 100% possible. That you can't save 100% on every level has always been part of the game. "Betcha can't save" is designed so that saving even one is difficult, and that shouldn't be messed with.

Agreed.

Quote from: roltemurto on April 04, 2026, 07:42:07 PM

Quote from: WillLem on April 03, 2026, 11:07:24 PMGood shout. I'll add Show/Hide Steel in the next update for sure.

Such a relief to hear this is possible. Thank you.

Added menu item and customisable hotkey (Ctrl + F2 by default) for Show/Hide Steel.

Implemented in SLXEditor commit 9ea1149.

Quote from: roltemurto on April 04, 2026, 07:42:07 PM"Grab lowest" toggle would certainly be useful I think.

After some investigation, it turns out that this is in fact what the "select piece below" (Alt + LMB) actually does: given a pile of pieces under the cursor, it will grab the lowest (give it a try!).

I've also fixed a bug with this: the hotkey would only work if there was no currently-selected piece under the cursor. This has now been fixed, so the hotkey will always cause the selection to re-trigger.

Fixed in SLXEditor commit 83d622d.

A hotkey to cycle through the pile is all that's needed, then. This has also been added: holding Shift whilst clicking LMB cycles selection through all pieces within 16px of the cursor (from lowest-highest).

Implemented in SLXEditor commit 2c6d3f2

Quote from: roltemurto on April 04, 2026, 07:42:07 PMAn "asset list" was exactly what I was trying to describe.

Ah, OK! In that case I've added this one to the to-do list. This one will likely take a bit longer, I'll post progress updates into this topic.

Quote from: roltemurto on April 04, 2026, 07:42:07 PMAt this point I'm not sure if show/hide option next to the layer counts as changing the layer system, but if that can also work, that would be a perfect UI in my humble opinion.

Auto-selecting the piece should be sufficient here. Showing each individual piece as its own "layer" could be done, but let's see if we need it first. That might be a good next step once the asset list (which I'll probably call the 'Pieces List' to keep it consistent with existing UI) is complete and working.

Quote from: roltemurto on April 04, 2026, 07:42:07 PMRest assured, the message bar pops up as intended, I haven't tried the buttons so I can't speak for sure for it's functions, but don't worry the bar and the message is there.

That's good to know, thanks for reporting back on this!

Version 1.7 Uploaded

Black Hole 18 Lemming Mayhem - changed fall distance to default of 126

Also includes a fully verified set of replays by ericderkovits.

Get the latest version here.

This pack has now been converted to .rlv for RetroLemmini. Post here if you encounter any issues playing this pack, have any replays to share, or general comments/feedback.

Enjoy MazuLems!

MazuLems - originally by Martin Zurlinden, converted by ericderkovits.

Eric's conversion notes

ok, Here is Mazulems For Superlemmini. I got the levels from the Lemmings level database. Only had to do a few minor edits.

Mazulems is a small pack(30 levels + 2 extra levels) which uses the standard styles and the original 8 skills.

The levels use the standard Amiga lemmings music track except for levels 18 to 23 which use the ohno music track (to match NL's version thanks to Swerdis's Youtube play of the pack.)

Just extract the .rar to the main Superlemmini folder (will fall into place). There will be 3 folders(levels folder, music folder which has the ohno tracks for the 6 levels (the other amiga lemmings tracks should already be in the music folder so no need to include those), and a replays folder)

Now here is another great pack for Superlemmini. I've already started posting replays for the pack on my youtube channel.

I managed save 3 on Betcha can't save just one!, save 4 seems impossible. Do we want to edit levels to make 100% possible? I'm 50/50 on whether we should tbh.

The lists I posted are just there to document my favourites, really. Of course I'd like to see them included, but I'm equally happy to leave level selection entirely up to Proxima; I'll ultimately back whatever he decides upon, even if it means some of my picks don't make the cut. I also strongly support Mobius' picks as well.

Good work so far, everyone, keep it up!

Quote from: roltemurto on April 02, 2026, 07:34:31 AMOn your concern about existing lemming effects (countdowns, balloon pop, etc.) potentially rendering beneath the foreground object: for this use case that's actually acceptable or even preferable. A timebomb countdown visible through a tunnel arch would look fine and is arguably better than it being hidden.

My concern is the opposite: the lemming being behind the paint object, but the effect (countdown, portal warp, etc) being above the paint object. There would likely be a way to sort this out, though.

Quote from: roltemurto on April 02, 2026, 07:34:31 AM- Additionally, when a lemming's position is covered by a FOREGROUND-flagged decoration, you can have the engine draw a simple outline or silhouette of that lemming to rlEffects as well, ater the decoration is composited. Since both would write to the same layer and decorations are drawn before lemmings in the pipeline, the outline would naturally sit on top of the foreground asset. I believe the infrastructure for this already exists in the codebase as the CombineFixedColor is already used for similar fixed-color overlay passes and the lemming's bounding rect is readily available at draw time.

Hmm. A good solution to the 'hiding the lemmings' problem, but by no means trivial to implement and, considering that the proposed feature is intended to be purely visual, could spoil the intended aesthetic somewhat...?

Quote from: roltemurto on April 02, 2026, 07:34:31 AMAnd sincerely thank you for keeping "The" nostalgia alive and keep improving it up to this day. I was stunned with disbelief when I discovered your fork (and NeoLemmix to be totally frank).
I wish you a great day!

Thank you for your kind words, I'm glad you're enjoying SuperLemmix!

I should've known. Good one!

Quote from: kaywhyn on April 02, 2026, 08:44:41 AMYes, splitting the current v4.0 RotL pack into two packs of 120 levels each and then as a result Lemmings Assemble is its own thing independent of any of the RotL packs (save for any levels that get used from the Outtakes and overflow/extra pool) available makes complete sense to me now.
...
I agree about not leaving the 2022 RotL pack the way it currently is

Glad to know. It's important that we all want the same thing here, and we seem to (which is great!)

Quote from: kaywhyn on April 02, 2026, 08:44:41 AMI don't think it'll be possible to fix all backroutes with only one update ... Here, I would suggest giving it maybe 3 versions, similar to how you detailed me your approach to backroute fixing your levels

Absolutely, that's reasonable.

The only thing I'd suggest is that perhaps rather than a fixed number limit, it may be best to set a deadline after which "no more fixes" is put in place (similar to namida's approach with NL). That might be more appropriate for this particular project, and means that you can revise levels as many times as you see fit up until that date.

It's ultimately up to you how you want to approach this, though. Whatever you think is best.

Quote from: kaywhyn on April 02, 2026, 08:44:41 AMOne thing, and that is I would suggest letting the poll run its course first before we commit to our duties.

Agreed, with the exception of Proxima drafting the first pack. It's a good way to get the ball rolling, and is unlikely to be impacted too much by the votes anyway.

Quote from: Proxima on April 03, 2026, 10:27:35 AMmy hope is that by putting in the work now, we'll reach a version we're happy to sign off on as the definitive final version so that no long-term maintenance is necessary (especially as the NL engine will now have no further updates). If more backroutes turn up later, we just accept that the pack isn't perfect.

Strongly, strongly agree.

Whatever kaywhyn decides as regards to backroute-fix limits, it seems to be clear to all of us that there should be a limit, and that limit shouldn't be surpassed, at least not by any of us.

One of the main purposes of this project is to have a set-and-forget couple of packs which don't need endless maintenance, and then a new pack to which we can add levels going forward.

Quote from: Proxima on April 03, 2026, 10:27:35 AMI'd like it to be done so that I can move on and get back to finishing my own pack (which I have been promising to do for years at this point).

Can't wait!

Quote from: WillLem on April 03, 2026, 11:28:22 PMJust to add my own two cents to this, here are my favourite levels so far (which I'd be sad to see removed unless they're present in another pack somewhere):

NOTE: I'll update these lists later as I'm still working my way through the pack - when I do update them, I'll repost the lists for convenience.

WillLem's favourite ROTL levels

Rounds and swingabouts
Bat country
No loitering
Crystal caves
Lem dunk (a save all solution would be nice)
Brick City
Crossing The Chasm
Harder, Better, Miner, Stronger
Don't Leave Me Hanging!
Lempire State Building
Use the grey matter for this one
Think Again!
Betcha can't save just one! (a save all solution should be possible, though)
Fiery Depths
The Climbing Frame
A break in the pillar
Dilemma

And, some that I've identified as possible levels to remove:

Candidates for removal

Build it up with iron and steel - far too pixel-precise, at least in the RL version. If kept, it should be revised to allow more margin for error
Subterranean - this one look fairly ugly due to what I can only imagine are backroute-fixes which pretty much give away the solution. I'd suggest revising the backroute fixes or removing the level
Crossing Paths Part Two - not as interesting as part one, and easier. The two could swap places!

Also, I voted for "keep them in the level pool". Reason: there seem to be other levels present in ROTL which are part of packs elsewhere (example: Think Again! by Wierdy Beardy), so it does seem a bit of an unfair reason to remove them. Perhaps instead of making "exists elsewhere" a criteria fr removal, choose some limit for how many of an individual author's levels can be present. This limit can be made less arbitrary by basing it on what's needed to actually fill the pack, of course.

Just to add my own two cents to this, here are my favourite levels so far (which I'd be sad to see removed unless they're present in another pack somewhere):

NOTE: I'll update these lists later as I'm still working my way through the pack - when I do update them, I'll repost the lists for convenience.

WillLem's favourite ROTL levels

Rounds and swingabouts
Bat country
No loitering
Crystal caves
Lem dunk (a save all solution would be nice)
Brick City
Crossing The Chasm
Harder, Better, Miner, Stronger
Don't Leave Me Hanging!
Lempire State Building
Use the grey matter for this one
Think Again!
Betcha can't save just one! (a save all solution should be possible, though)
Fiery Depths
The Climbing Frame
A break in the pillar
Dilemma

And, some that I've identified as possible levels to remove:

Candidates for removal

Build it up with iron and steel - far too pixel-precise, at least in the RL version. If kept, it should be revised to allow more margin for error
Subterranean - this one look fairly ugly due to what I can only imagine are backroute-fixes which pretty much give away the solution. I'd suggest revising the backroute fixes or removing the level
Crossing Paths Part Two - not as interesting as part one, and easier. The two could swap places!

Thanks for your suggestion.

This is definitely a problem I recognise. I often find myself having to manually move pieces out of the way to get to the piece I actually want, then move the pieces back to their original position afterwards. We definitely need a solution to this, for sure.

The "select pieces below" hotkey (Alt + LMB by default) does work some of the time, but becomes difficult or impossible to use properly when there are multiple overlaying pieces. It's here in the Hotkey Config btw, should you wish to remap it to something else (Tools > Configure Hotkeys):



We can do better than this though.

To respond to your suggestion: I'm imagining that by "layers system" you mean some way of adding pieces to a base layer, then add a new layer and add more pieces there, then another layer and add more pieces there, etc. Then, be able to switch between the layers as needed. If this is what you mean, then I'm not sure I agree that a layers system is the best way to solve this problem, as it would overcomplicate rendering and give the user more UI stuff to keep track of. It just about works for image editing, but I don't think it would be a good fit for a level editor tbh.

However, since the main concern seems to be more with being able to select a certain piece more easily, there are definitely other ways we can achieve this. So, I've re-titled the topic accordingly and we can explore the various options.

To respond to some specifics in your original post:

Quote from: roltemurto on April 03, 2026, 02:49:08 AMFor my particular problem; an option to Show/Hide Steel (like any other layer) would solve it immediately.
Steel is the only asset type that hasn't got an option to hide/show.

Good shout. I'll add Show/Hide Steel in the next update for sure.

Quote from: roltemurto on April 03, 2026, 02:49:08 AMAn option in the settings or a modifier key press; that simply allow bypassing the alpha channel when selecting, would also save me right now.

This one could be done, but then the selection rectangle becomes somewhat redundant. We'd need to wrap the solid pixels with an exact outline (think 'magic wand' selection in image editors) and have that be the selectable area: not trivial to implement by any means, and still doesn't always guarantee selectability (which is what we're trying to achieve here). It's an interesting idea, though, and could be good for piece selection in general. Maybe one to come back to later.

Quote from: roltemurto on April 03, 2026, 02:49:08 AMWhat would be a QoL update is; an actual toggle button to let the cursor prioritize and select the layer at the back/behind.

This is closer. A hotkey that allows the player to 'walk' the selection through the pieces currently under the cursor could be extremely useful. Using the cursor location as a reference, hold the hotkey, and click the LMB until the piece you want is selected. This could solve the problem entirely, and wouldn't be too difficult to implement. 'Grab lowest' and 'grab highest' could also be done.

Quote from: roltemurto on April 03, 2026, 02:49:08 AMWhat would be an even better addition; is the layer system implementation;
Currently there is no way to tell how many layers are there or which and what layers are currently on the map.
...
If there was a file list ... that would allow...

The render layers are (from lowest to highest): background, objects low, terrain (inc. steel), objects high, rulers. Each piece is then drawn to its own 'layer' within that system, ordered by index. To implement a separate 'layers' system, this framework would have to be duplicated, which could get messy very quickly.

Conversely, the "asset list" you've hinted at is an interesting idea that could work perfectly alongside what's already there. We could have a pop-up list (which can be closed or opened at any time) which simply lists every piece active in the level, in index order and with details such as location, render layer, whether it's an eraser piece, etc. Clicking a piece on the list could then select it in the level arranger (and vice versa). This could work, for sure, and would be much simpler to implement and maintain than a layers system. "Move Up", "Move Down" and "Delete" buttons could also be added for convenience.

Quote from: roltemurto on April 03, 2026, 02:49:08 AMThis also makes it impossible to clean/delete an asset that has been removed/changed from the style folder,
because there is no way to select it once the editor is restarted, the level is reloaded or simply the styles has been refreshed.

Not so. Missing pieces can be deleted by simply opening a level that contains missing pieces; the Editor will identify them, and they can then be deleted by choosing "Delete Missing Pieces" from the status bar menu. If you're not seeing the status bar message when you open a level with missing pieces, then this could be a bug. This is what you should see:



Please let me know if you do not see this message when opening a level with missing pieces. You should also see it after refreshing styles (if a piece becomes missing due to the refresh).

Quote from: roltemurto on April 03, 2026, 02:49:08 AMI hope I was able to explain the situation that I am struggling with.

Absolutely, and it's something that I too struggle with now and again. You've given me a nudge to finally do something about it!