mojira.dev

John Mitchell

Assigned

No issues.

Reported

MC-198600 Vanilla server crashes when aggro'd player travels from nether to overworld Awaiting Response MC-190279 Witches spawn on the corners of blocks in swamp huts Cannot Reproduce MC-186701 Detector rails lose track of minecarts when at large distances from world centre (10 million or greater in general) Duplicate

Comments

Ill talk to the owner and try to get a copy of the log

Apologies for the delay, the bug is NOT present in 1.16, so I assume testing for older versions is not needed.

I haven't had a chance to test this in 1.16 yet but I will do so later today. Additionally, I have also discovered since reporting this that it is not limited to witches. It occurs for all hostile mobs in the effected area, and I haven't had a chance to observe other mob types thus far. My guess is that it's something to do with how far away I am from spawn, but I've got no idea what the lower bound is for this occurring. 

I don't know if this occurs in previous versions, but the sheer number of previous versions to test it in makes me reluctant to try, although I might give 1.12, 1.13, and 1.14 a shot on their most developed releases. 

Finally, some interesting observations:

  1. Mobs spawn specifically in the north west corner of the selected block for spawning.

  2. Even if the selected block for spawning is an air block, the mob may still spawn given that one of the three other blocks that shares a corner with the north west corner of the spawning block is also a valid spawning block. This particular observation isn't definite, but is at least a representation of what happens visually

  3. Also not a definite observation, but mobs only appear to be selecting every second block for spawning. That is, only if both the X and Z co-ordinates of the block are divisible by two. If this is consistent, it implies that only 25% of all of the blocks are spawning mobs.

Again, these are not concrete and proved, but are at least consistent with what happens visually. I will try to record some examples of these observations.

As MC-186701 is no longer open, I'll add some of the information here as well. 
The issues start with the detector rails when either the X or Z co-ordinates are greater than or equal to 16777216, or 2^8. Seems like an awfully big coincidence that it occurs after exceeding the limitations of an 8 bit number, but obviously it could be for a variety of reasons none of which I am informed enough to speculate on. 

This bug, for me at least, has been a pain to deal with. I ran into it while trying to make a vital redstone machine on an anarchy server (the kind of server where you want to be extremely far from spawn) and as a result, we have to abandon our current location entirely and move closer to the world centre where this won't occur.

I'm sure that this has been a problem for other people, albeit for perhaps entirely different reasons.