Factorio Forums

This is a bug which I encountered a long time ago, thought it had been fixed but it's still there.
Sometimes, after rail placement, signal placement is only enabled at one side of a track, not on both.
Track are supposed to be left-hand-drive, but I placed it in the opposite direction.
Created the upper tracks with FARL and several other Mods active in 0.18.1, but still persists after disabling all Mods and patch 0.18.2


In Screen #1, the complete rail line is f***ed up.
In Screen #2, i removed a short piece. Now to the left it's okay, to the right (the long one to the other side of the map) still bugged.
After reconnecting both tracks, it gets f***ed up again.
with all mods enabled: mods disabled (still there..):

This is working as intended. This rail segment was deduced to be one-way because of rail signal at {x=813.5, y=119.5}. If you want to place signal on opposite side, first place rail signal on "wrong" side and there will be white position marker on opposite side (or go and remove above mentioned rail signal and its friend to the right)

To me this is a feature. Without it indicating that you signaled a segment to be one-way (by only showing you possible placements on one side) it could quickly be rendered impassable by unintended off-setting signals leaving you wondering why you have trains that can't path.

I wondered about the same thing some time ago and - IIRC - even reported that as a bug, too. But getting a bit used to that - and with the reasoning given here - this system as-is works actually better and is more intuitive than allowing to place signals everywhere irrespective of the currently-chosen drive direction of a piece of track.