Non-100% levels: How many more skills needed for 100%?

[ccexplore]

Curiously enough, when I play the level in DOSBox I get the "lite" version too. I'm almost certain both DOSBox and Lemmix are reading from the same levelpack file, since I don't have multiple copies of it. IIRC my version is from Abandonia.

Ooh okay, I see now. <lightbulb> In that case it's smelling like a Lemmix bug.  Perhaps the terrain data in question in the level file are marked in such a way that's not the usual "valid" combinations of flags, and Lemmix interprets the combination one way while Lemmings does it differently.  (I'm discounting the possibility that it's a DOSBox bug since it's too much of a coincidence that only the decorative terrain are different, but if someone can check the level in real DOS, please do so.)

It would be interesting for someone to check what the level looks like in LemEdit.  Not that LemEdit's rendering is guaranteed to be 100% compatible with Lemming's, but it's an interesting thing to compare.   Also of interest would be if someone try cgalemmi.exe to see how the level renders in the CGA version.

(I would do it myself right now, but it looks like the copy on the computer I'm on at the moment is missing all these things I need to check.)

With this new information in mind, I think we'd have to say that only solutions that work on the "no decorative terrain" version counts.  There are no two versions of the level; it now looks like it's just one version, but rendered differently in Lemmix vs PC Lemmings.

[geoo]

Yes, LemEdit doesn't display the additional terrain, while Lemmix displays it with exactly the same level.

Simon also tested with CGALemmi, and it doesn't display the additional terrain either.

[ccexplore]

Ok, found the underlying cause.  In Taxing 27's (decompressed) level data, the 4 bytes corresponding to terrain at index 68 is (in hex) FF FF 22 A6.  rt's Lemmings file format document says that unused terrain slots are filled with FF FF FF FF, but it's likely that the actual Lemmings game simply checks for the first 2 bytes being FF FF as an indicator that it has reached the end of the list of terrains.  As a result, in PC Lemmings no terrain past index 67 will load in that level, whereas Lemmix will happily go past index 68 and keep loading terrain beyond, until FF FF FF FF is reached at a much higher index.

It's unclear whether this arrangement is intended or accidental.  Certainly there's no saving in disk space given that the terrain data for almost all the decorative terrain are all still in the level data.

I've attached a modified version of the level that renders in Lemmix the same way (I think) the original version does in PC Lemmings.

When I have time later this week, I'll check and see if any other PC Lemmings levels exhibit similar symptoms.

[Clam]

Seems to me like an intentional hack to make all the "excess" decoration disappear. Maybe drawing all that extra terrain was making the game run slowly?

I notice this errant terrain piece shows up in Lemmix at x=4079 - way off the edge of the map. Looking at the file format and testing a bit in Lemmix (terrain wraps around every 4096 pixels), this is exactly where it should end up if the first two bytes are FF FF. So any level where this has been done (if indeed it is intentional) should have a terrain object in that position.

[ccexplore]

I guess the momentum didn't last long on this challenge.

Here's a stab at Taxing 28, modeled closely after the lose-10 solution.  While I think there may be a slight chance you can get the landing place ready by 10th lemming out, the saving of a floater is outweighted by extra skills I think you'd have to add in that case to finish the level.  Mine added 10 skills, namely 9 floaters and 1 basher.

[edit: incidentally, the table has wrong results for Tricky 17 and Mayhem 26.  Both should be 2 not 1]

[Clam]

I did Taxing 27 with 4 extra skills, 1 builder and 3 diggers (alternatively, swap the builder for a basher). As it turns out, the "extra" terrain doesn't help at all, even if you were to allow it (though it was certainly a nice discovery ).

[ccexplore]

Good job! But I was able to improve on Clam's solution slightly so that only 3 extra skills need to be added, namely 2 diggers and 1 miner.  I also arrange for it so that you don't need to assign 2 skills on consecutive frames (though the pixel precision remains).

[Clam]

Mayhem 29 is a tough one, whichever way you try to do it. Here's an initial stab that takes 7 extra skills: 3 builders, 2 miners and 2 diggers. This is based off my own 78/80 replay that I made some time ago (since I haven't found such a replay anywhere else), so it's possible there's a more efficient way of handling the start.

[ccexplore]

As predicted, the start of Mayhem 29 can be optimized so that the extra builders aren't needed, but I haven't found any improvements to the end part on the left.  So new result is 4 more skills for Mayhem 29.

[Clam]

Wow, that is impressive! This solution probably carries over to the minimum skills with max % challenge as well.


A couple quick ones from Holiday lemmings:
Flurry 16 takes 1 digger extra.
Frost 14 needs 2 skills, 1 blocker and 1 basher. Replay attached, since the method of setting and releasing the blocker isn't obvious.

[Clam]

Looks like no one wants to do the last couple of levels, so I'll do them now.

Blitz 15: 5 skills (3 builders, 1 basher, 1 digger)
Blitz 16: 2 skills (2 diggers)

Replays attached.

[ccexplore]

Here's one more improvement before we move on to some other challenge.  Crazy 14 with 2 added skills: 1 builder and 1 miner.

[Clam]

I found a much simpler way using 2 extra builders and no miners. Neither method seems to show any room for improvement though.

As for other challenges, they might just have to wait until we get some more people willing to carry on with these. Everyone seems to be busy with other things at the moment (including myself to some extent).

[Simon]

It's hard to get people together... I won't usually get motivated for these things unless I'm voicechatting with geoo. But most things have their downtimes and will come back eventually.

-- Simon

[Pooty]

Because a 100% solution has now been found for Wicked 9, that level needs to be omitted from this challenge.