[1.12.2] Chisel world style is corrupted with a sufficient amount of content mods installed

HariboTer commented 3 years ago

(I wish I could specify a concrete other mod as cause of the problem, but I'm honestly convinced it is that broad an issue.)

After adding mod after mod to my custom modpack during the last few months, I recently created a new world to find out my lost cities with chisel world style now look like this:

2020-07-14_16 50 21

(Yes, those houses are built out of decorative candles and lantern posts from ATLCandleCraft. I have not modified a single asset file from this mod.)

Now, in my current survival world generated half a year ago, it didn't look like that, so what followed was hours and hours of trying to pin it down to a minimal mod selection that would cause it. Despite repartitioning the active mods and relaunching Minecraft over and over, applying a binary search procedure first for a single third mod to cause the problem (which failed twice), then for a combination of two mods to cause the problem and ultimately maybe three mods to cause the problem and then experimenting some more just to be sure, I am very certain now the problem is not a specific other mod, but that the Lost Cities generator gets confused by the range of block IDs that NEIDs makes possible.

When I remove just a few mods, the image above looks like this (recreated world with the same seed):

2020-07-14_16 18 21

(It's leaves and planks from Biomes O'Plenty now.)

When I remove a few more mods, it changes again to redstone repeaters and pumpkins.

When I remove even more mods, it goes back to normal.

To emphasize, with one half of my mods it works fine. With the other half it works fine too. I can usually go up to 3/4 of my mods before it starts breaking, and when I try to isolate the mods near the "breaking point" and run it only with them, it works fine again too.

The vanilla block generation still works fine though (this image was generated with the same selection of mods as the last image, but with the default world style instead of Chisel):

2020-07-14_16 25 01

My modlist:

All ~400 mods

I know that this is a bit of a niche case, but I'd really like LostCities' chisel buildings to generate properly again when I go exploring in my modded survival worlds, so it'd be much appreciated if you could look into this.

McJty commented 3 years ago

You probably added NotEnoughIDs or something to bypass the ID limit? In that case this is to be expected. The ID's have changed of several blocks and this causes problems here

HariboTer commented 3 years ago

Every image is from a freshly generated world each. I did especially neither add nor remove NotEnoughIDs to/from a world, it was active the whole time.

McJty commented 3 years ago

I think the problem has to do with going over the block id limit though. Not sure there is anything that I can do to fix this. At least I don't know how

HariboTer commented 3 years ago

Is it possible that at some point, the generation code uses numerical block IDs with a small integer data type (perhaps short) that would be overflowing?

McJty commented 3 years ago

yes it certainly does. That's how Minecraft chunks work. Every block in a chunk is stored with 16 bits. 12 bits for the ID and 4 bits for metadata. But that's not a Lost Cities limitation. That's how vanilla does it. What mods like NotEnoughIDs do is to add the MC 1.13+ solution to this so that every chunk can have a different palette of blocks. BTW. Check the lost cities general config. There is a setting for a safe mode (I thought that should be auto detected but maybe that got broken)

HariboTer commented 3 years ago

Do you mean optimizedChunkgen? Setting it to false to be sure was among the first things I did, every test listed in the OP was performed afterwards.

(I'll check now if other chisel structures generate correctly and if chisel blocks can be placed and loaded regularly.)

McJty commented 3 years ago

Then I have no clue what's going on. Sorry...

HariboTer commented 3 years ago

The problem is specific to the LostCities, structures and terrain from every other mod (including, but not limited to Techguns, Electrobob's Wizardry, Ancient Warfare, Biomes O'Plenty and UntergroundBiomes) is still generated correctly (especially the Chisel structures from Techguns).

I think at some point, the numerical IDs get stunted somehow through one or more conversions.

(As further note of interest, the exact same problem occurs when switching NEID out for JEID.)

McJty commented 3 years ago

Perhaps. But in any case. I no longer work on 1.12 and I also strongly dislike hacks like NEID and JEID so I don't really want to support them to much. So this will most likely not get fixed

HariboTer commented 3 years ago

So I just about traced the life of a block type from palette asset loading to setting the chunk primer data and the only thing I could find is that Block.BLOCK_STATE_IDS, which is used a lot for char/BlockState conversion, is marked as deprecated, though I do not know if that would relate to the problem.

One interesting thing I noticed by having tellme dump the block IDs though is that the difference between the block IDs that are placed (in the 730s) and the block IDs that are supposed to be there (in the 4830s) is precisely 4096.

Since the cause may thus indeed be out of LostCities' reach, I'll report this to the JEID team, maybe they have more insight to share about this.

McJtyMods / LostCities

[1.12.2] Chisel world style is corrupted with a sufficient amount of content mods installed #308