MC-18251415 Block States per SubChunk Limit during World Upgrade
The bug
If there are more than 15 different block states (Excluding air) in a single subchunk when upgrading the world from 1.12.2 to 20w18a, the entire 256 high chunk will be reset back to default terrain.
It was working perfectly fine in 20w16a, but broke in 20w17a.
Upgrading the world from 1.13.0 works perfectly fine in 20w18a
To reproduce
- Create a normal superflat world in 1.12.2
- Add 12 different blocks to a single subchunk (12 blocks + grass + dirt + bedrock = 15 blocks)
- Add 13 different blocks to a different subchunk (13 blocks + grass + dirt + bedrock = 16 blocks)
- Upgrade the world to 20w17a+
→
The 1st chunk will be perfectly fine
→
The entire 2nd chunk will be reset to default terrain
Stack trace
[12:38:43] [Server thread/ERROR]: Couldn't load chunk [-64, 40] java.lang.NullPointerException: null at cgo.a(SourceFile:122) ~[20w18a.jar:?] at cgu.a(SourceFile:249) ~[20w18a.jar:?] at it.unimi.dsi.fastutil.ints.Int2IntOpenHashMap$MapEntrySet.forEach(Int2IntOpenHashMap.java:927) ~[fastutil-8.2.1.jar:?] at cgu.a(SourceFile:249) ~[20w18a.jar:?] at cgo.h(SourceFile:121) ~[20w18a.jar:?] at cgz.a(SourceFile:101) ~[20w18a.jar:?] at yf.l(SourceFile:525) ~[20w18a.jar:?] at java.util.concurrent.CompletableFuture$AsyncSupply.run(CompletableFuture.java:1771) [?:?] at alu.c(SourceFile:144) [20w18a.jar:?] at yr$a.c(SourceFile:540) [20w18a.jar:?] at alu.w(SourceFile:118) [20w18a.jar:?] at yr$a.w(SourceFile:549) [20w18a.jar:?] at yr.d(SourceFile:280) [20w18a.jar:?] at net.minecraft.server.MinecraftServer.bc(SourceFile:777) [20w18a.jar:?] at net.minecraft.server.MinecraftServer.w(SourceFile:765) [20w18a.jar:?] at alu.c(SourceFile:127) [20w18a.jar:?] at net.minecraft.server.MinecraftServer.v(SourceFile:750) [20w18a.jar:?] at net.minecraft.server.MinecraftServer.b(SourceFile:532) [20w18a.jar:?] at net.minecraft.server.MinecraftServer.i_(SourceFile:372) [20w18a.jar:?] at enx.d(SourceFile:65) [20w18a.jar:?] at net.minecraft.server.MinecraftServer.run(SourceFile:673) [20w18a.jar:?] at java.lang.Thread.run(Thread.java:835) [?:?]
Linked Issues
Attachments1
![[Mod] violine1101](../../../data/avatars/users/92858.png){kind=small}
Created Issue:
15 Block States per SubChunk Limit during World Upgrade
If there are more than 15 different block states (Excluding air) in a single subchunk when upgrading the world from 1.12.2 to 20w18a, the entire 256 high chunk will be reset back to default terrain.
It was working perfectly fine in 20w16a, but broke in 20w17a.
Upgrading the world from 1.13.0 works perfectly fine in 20w18aCreate a normal superflat world in 1.12.2
Add 12 different blocks to a single subchunk (12 blocks + grass + dirt + bedrock = 15 blocks)
Add 13 different blocks to a different subchunk (13 blocks + grass + dirt + bedrock = 16 blocks)
Upgrade the world to 20w17a+
The 1st chunk will be perfectly fine
The entire 2nd chunk will be reset to default terrainAs people are still using 1.12.2 for performance reasons, this should not be marked as "Won't Fix".
relates to
![[Mojang] Bartosz Bok](../../../data/avatars/users/10122.svg){kind=small}
[Mojang] Bartosz BokIf there are more than 15 different block states (Excluding air) in a single subchunk when upgrading the world from 1.12.2 to 20w18a, the entire 256 high chunk will be reset back to default terrain.
It was working perfectly fine in 20w16a, but broke in 20w17a.
Upgrading the world from 1.13.0 works perfectly fine in 20w18aCreate a normal superflat world in 1.12.2
Add 12 different blocks to a single subchunk (12 blocks + grass + dirt + bedrock = 15 blocks)
Add 13 different blocks to a different subchunk (13 blocks + grass + dirt + bedrock = 16 blocks)
Upgrade the world to 20w17a+
The 1st chunk will be perfectly fine
The entire 2nd chunk will be reset to default terrainAs people are still using 1.12.2 for performance reasons, this should not be marked as "Won't Fix".
The bug
If there are more than 15 different block states (Excluding air) in a single subchunk when upgrading the world from 1.12.2 to 20w18a, the entire 256 high chunk will be reset back to default terrain.
It was working perfectly fine in 20w16a, but broke in 20w17a.
Upgrading the world from 1.13.0 works perfectly fine in 20w18aTo reproduce
- Create a normal superflat world in 1.12.2
- Add 12 different blocks to a single subchunk (12 blocks + grass + dirt + bedrock = 15 blocks)
- Add 13 different blocks to a different subchunk (13 blocks + grass + dirt + bedrock = 16 blocks)
- Upgrade the world to 20w17a+
→
→
The bug
If there are more than 15 different block states (Excluding air) in a single subchunk when upgrading the world from 1.12.2 to 20w18a, the entire 256 high chunk will be reset back to default terrain.
It was working perfectly fine in 20w16a, but broke in 20w17a.
Upgrading the world from 1.13.0 works perfectly fine in 20w18aTo reproduce
- Create a normal superflat world in 1.12.2
- Add 12 different blocks to a single subchunk (12 blocks + grass + dirt + bedrock = 15 blocks)
- Add 13 different blocks to a different subchunk (13 blocks + grass + dirt + bedrock = 16 blocks)
- Upgrade the world to 20w17a+
→
→Stack trace
[12:38:43] [Server thread/ERROR]: Couldn't load chunk [-64, 40] java.lang.NullPointerException: null at cgo.a(SourceFile:122) ~[20w18a.jar:?] at cgu.a(SourceFile:249) ~[20w18a.jar:?] at it.unimi.dsi.fastutil.ints.Int2IntOpenHashMap$MapEntrySet.forEach(Int2IntOpenHashMap.java:927) ~[fastutil-8.2.1.jar:?] at cgu.a(SourceFile:249) ~[20w18a.jar:?] at cgo.h(SourceFile:121) ~[20w18a.jar:?] at cgz.a(SourceFile:101) ~[20w18a.jar:?] at yf.l(SourceFile:525) ~[20w18a.jar:?] at java.util.concurrent.CompletableFuture$AsyncSupply.run(CompletableFuture.java:1771) [?:?] at alu.c(SourceFile:144) [20w18a.jar:?] at yr$a.c(SourceFile:540) [20w18a.jar:?] at alu.w(SourceFile:118) [20w18a.jar:?] at yr$a.w(SourceFile:549) [20w18a.jar:?] at yr.d(SourceFile:280) [20w18a.jar:?] at net.minecraft.server.MinecraftServer.bc(SourceFile:777) [20w18a.jar:?] at net.minecraft.server.MinecraftServer.w(SourceFile:765) [20w18a.jar:?] at alu.c(SourceFile:127) [20w18a.jar:?] at net.minecraft.server.MinecraftServer.v(SourceFile:750) [20w18a.jar:?] at net.minecraft.server.MinecraftServer.b(SourceFile:532) [20w18a.jar:?] at net.minecraft.server.MinecraftServer.i_(SourceFile:372) [20w18a.jar:?] at enx.d(SourceFile:65) [20w18a.jar:?] at net.minecraft.server.MinecraftServer.run(SourceFile:673) [20w18a.jar:?] at java.lang.Thread.run(Thread.java:835) [?:?]
![[Mojang] Adrian Östergård](../../../data/assets/gravatar/nighter.jpeg){kind=small}
Very Importantrelates to
![[Bot] Piston](../../../data/avatars/users/31202.png){kind=small}
Can confirm fixed. Worlds can be opened in 20w19a, however all chunks are reset, which might be MC-182514.
Confirmed. Here's a test world: upgrade.zip
.