Error in relation with usable map entities

[mexikoedi]

Your version of TTT2 (mandatory)

• TTT2 v0.14.0b Workshop version from Steam

Describe the bug (mandatory)

This error only occured on one map. I don't remember on which one but it occured if you try to interact with something or something in that direction. Maybe because of weird usable map entities like levers or chests which are not correct placed on the map or something like that.

To reproduce

Steps to reproduce the behaviour:

1. Go onto some maps (maybe Minecraft maps)
2. Interact with usable entities like levers, chests, ...
3. See error

Expected behaviour

This error shouldn't happen.

Context (please provide as much as you can)

• Collection link of your Server: https://steamcommunity.com/sharedfiles/filedetails/?id=1822673195
• Server error in the server console:

[TTT2 (Base) - v0.14.0b] gamemodes/terrortown/gamemode/server/sv_entity.lua:88: Tried to use a NULL entity!
  1. ObjectCaps - [C]:-1
   2. IsUsableEntity - gamemodes/terrortown/gamemode/server/sv_entity.lua:88
    3. func - gamemodes/terrortown/gamemode/server/sv_player.lua:533
     4. unknown - lua/includes/extensions/net.lua:38

[TimGoll]

I will keep this in mind and take a look at the code. But it is probably hard to debug if I can't reproduce it. I tested A LOT of minecraft maps in the last two weeks, without this error ever appearing

[mexikoedi]

I will keep this in mind and take a look at the code. But it is probably hard to debug if I can't reproduce it. I tested A LOT of minecraft maps in the last two weeks, without this error ever appearing

I looked through the logs and it happened on the map "ttt_troubleisland". So the "Minecraft" part is not important.
Here the link: https://steamcommunity.com/sharedfiles/filedetails/?id=365484855

[TimGoll]

ttt_troubleisland

That helps a lot, thanks. Do you have any idea where on this map this happened?

[mexikoedi]

ttt_troubleisland

That helps a lot, thanks. Do you have any idea where on this map this happened?

I don't know. It was another player who caused this error. The map has teleporters so maybe that's the origin of this error.

[Histalek]

This shouldn't be possible under normal circumstances as the entity that is being used here has already passed an IsValid() check and can't be NULL.

but there is a non-zero chance that there is either something happening on the network layer, some client-server mismatch, garbage-collection shenanigans or a combination of those three

i still don't understand why this wouldn't already trigger the error in sv_player.lua as the entity will already be used there ...

[Histalek]

I'm not able to reproduce this on that map.
The useable map entities i've tried were the elevator buttons and the keypads to open the doors to the teleporters

[mexikoedi]

I'm not able to reproduce this on that map.
The useable map entities i've tried were the elevator buttons and the keypads to open the doors to the teleporters

It's hard to reproduce.
But we get this error at least once every other session but no one knows for sure why this error appears.
It also happens on other maps.
If it would help I could provide more/extended server logs. But I think these wouldn't help because all log entries around this error seem normal.