ooio

Copy pasting from MC-262021

I have found the cause of the issue.

When overworld side has no landmass or solid blocks to place the nether portal on, ie, the corner of the world is water/ocean OR player manually clears it out, the game fails to place a portal and this issue comes to be.

Only reason it occured on some seeds not on others was because seeds it failed at had ocean or river in the corner. While the rest of them, they had landmass.

This is easily reproducible on every seed, every world if player does a /fill in overworld side and manually removes the land/solid blocks.

In my case I ran these command,

/gamerule commandModificationBlockLimit 1000000
/fill 29999983 68 29999983 29999943 -64 29999947 air

Game tries to generate regular portal but fails. It is unable to place portal with platform as well. And now player is unable to go into overworld.

Game NEEDS 4 solid blocks in a straight line exposed to air in the corner chunk for it to be successful in generating a portal.

Works:

Fails:

As for the stacktrace seen in MC-262021

Game runs DistanceManager#removePlayer a second time after client sends position update packet. Since the player on server is out of nether but hanging in the middle of nowhere, the playersPerChunk field is empty and there being no null check for the returned object, it throws.

Expected Result:

Game should be able to generate floating portal with platform if its unable to generate portal without platform.

As for the stacktrace, 

Game runs DistanceManager#removePlayer a second time after client sends position update packet. Since the player on server is out of nether but hanging in the middle of nowhere, the playersPerChunk field is empty and there being no null check for the returned object, it throws.

I have found the cause of the issue.

When overworld side has no landmass or solid blocks to place the nether portal on, ie, the corner of the world is water/ocean OR player manually clears it out, the game fails to place a portal and this issue comes to be.

Only reason it occured on some seeds not on others was because seeds it failed at, had ocean or river in the corner. While the rest of them, they had landmass.

This is easily reproducible on every seed, every world if player does a /fill in overworld side and manually removes the land/solid blocks.

In my case I ran these command,

/gamerule commandModificationBlockLimit 1000000
/fill 29999983 68 29999983 29999943 -64 29999947 air

Game tries to generate regular portal but fails. It is unable to place portal with platform as well. And now player is unable to go into overworld.

Game NEEDS 4 solid blocks exposed to air in the corner chunk for it to be successful in generating a portal.

Works:

Fails:

Just tested in latest snapshot, instead of the stacktrace, it simply logs error "Unable to create a portal, likely target out of worldborder" and player never teleports into overworld. However unlike previous versions, it doesn't freeze or become unresponsive

Can confirm. AdyTech99's seed and coordinates do indeed result to same issue and same stacktrace.

This issue needs to be reopened.

I just tested it in latest snapshot and it seems to be gone. I guess this was fixed somehow. This bug report can be closed. Thanks

I had this happen to me in 23w18a on certain resolutions. FOV set to normal, VSYNC off (didn't seem to affect it), FPS unlimited (didn't seem to affect it)

Still happens in 22w19a

Duplicate of MC-249930

more fun

Duplicate of MC-249927 

Fun