I think this solution is only fixing a symptom and not the core bug while introducing undeterministic save behaviour (we already have some but I want to get red of that completely because it creates versioning noise and easily breakes your maps)

CC @DasCapschen

I'm not sure, but wouldn't using the camera origin mean that track objects could end up in the wrong chunk? Especially if the camera is in one chunk and the rail in another, e.g. due to being close to a chunk's edge?

If I understand correctly, the issue is that the rail origin may not be set (e.g. is 0,0,0). The function _spawn_poles_for_rail is called as part of _spawn_rail, which instances the rail. However, the rail position is only set after calls of _spawn_rail, so may not be set at the time _spawn_poles_for_rail is run.

Here's an example of _spawn_rail being used (taken from Editor.gd lines 734-741):

var rail2: Node = _spawn_rail()
rail2.translation = selected_object.end_pos
rail2.start_pos = selected_object.end_pos
rail2.rotation.y = selected_object.end_rot
rail2.start_rot = selected_object.end_rot
rail2.radius = 0
rail2.length = y_length - x_length
rail2.update()

Perhaps we should adjust _spawn_rail to take a position as a parameter and have it set the translation before _spawn_poles_for_rail is called? I'm not sure what else would be affected though.

track objects could end up in the wrong chunk

This is a valid remark, let me dig into this

I'm with @nalquas on this one. _spawn_rail() should probably specify the rail position right away.
Also, iirc, we added the chunk of the rail to its metadata at some point. Maybe this should happen in _spawn_rail() too. Then we do not have to calculate the chunk for the rail's track objects.

There's an Edge Case also, which I'm not sure is currently covered:

• if the rail itself is moved, the chunk must be recalculated and all track objects must be moved to the new chunk...
• instead of doing that every move, do it on save ?

instead of doing that every move, do it on save ?

@DasCapschen I thought it's done on save already? Or do I confuse that with the chunk manager and the conversion?