Minecraft Forums

Start here, on spiders, and keep clicking related links. https://mojang.atlassian.net/browse/MC-1241
There are hundreds of instances of position glitches in the game. They have always been in the multiplayer game, and were introduced to single player when they merged the code. I expected they would have worked on it by now, but no sign so far. What's the effect?

Spiders fall through the floor then jumping back up so you can't hit them, but if you walk into their virtual space, they hit you, and update to be actually through the floor.

Mobs run around 1 block into the dirt. Players appear to be in the dirt, but only from the other's perspective.

Stuff riding in carts disappears or desyncs.

Riding a boat virtually through space while actually staying in one spot.

Sheep escaping from a fully fenced enclosure.

I could go on.

I know it's a client/server thing, but at least they could do something like make the server arbiter of position and correct the client. Or something. But they seem to just ignore this one even though it impact's everyone's gameplay. Can we do something?

There has to be an 'off by one' type bug in the client server protocol. But obviously it doesn't happen all the time, if it did it would be easy to fix. Obviously both the client and the server know where blocks are, and know that they are solid, but the client must interpret a position it gets from the server as being inside the block. Neither the client nor the server would place the mob there...

"Can we do something?" Sure, you could study the source and try to identify the bug yourself if you wish. The code is available to you via the MCP.

I don't intend to get into the MC source code. I just want to raise this issue so Mojang makes it a priority. I don't know if it's just an off-by-one thing or some more insidious problem with asynchronous code, but it needs to be dealt with.

This bug (plus lag) is also the main reason why combat is stuck in "spam your sword" mode. If they could find a solution, so you can know where your enemy is, and your enemy is actually where it should be, that would help so much, and make it possible to add skill.

So how can we raise this issue to top priority in Mojang? How can we get them to fix it?

I've voted on bugs, but nothing is happening since last year. I know this post won't get their attention. I think we need either attention from players who can cry out for change, or from modders who can find a fix. But maybe I'm wrong and most people don't care. Do people not care much about these bugs?