Correct LoD distance

[atirut-w]

Got to figure out how to calculate or get the near fade distance somehow.

[Koalamana9]

This can be done with a simple distance check, but for that to work all LOD'ed world must be in a Godot scene and then higher LOD's streamed in and out from memory.
Biggest problem is that Godot doesen't have any asset streaming functionality build-in.