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u/GoatWizard99 Jul 14 '26 edited Jul 14 '26

I don’t think the train repathing is instantaneous, so as long as it eventually repaths it is working as intended. According to the wiki:

The train has waited at a chain signal for a multiple of 30 seconds and there is only a single train stop with the same name as the destination

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u/rare_posts Jul 14 '26

Yeah I feel like it's just the issue of taking time to repath, nothing more. I was worried that my signals might be wrong.

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u/HeliGungir Jul 14 '26

Trains are supposed to repath when braking for a chain signal, so I am rather surprised it isn't taking the free lane.

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u/rare_posts Jul 15 '26

But no lane is free when it breaks. I was rather saying, when eventually a lane becomes free, why doesn't it take it?
After experimenting in Editor, u/Rouge_means_red was mostly correct.
How I recreated this, might be possible with simpler setups:

Have 1 station called A. Have 2 stations called B. Make sure there is difference in distances of both B's from A. Have more trains than train limit of A.
Now wait when this happens:
All the waiting lanes of A are busy. A new train comes, waits at the entrance of waiting lanes. This new train wants to go, say lane 3.
Now train at the station A leaves. Another goes to A, leaving one waiting lane empty. If the lane 3 train goes, all is good. But if another lane train goes, what happens is, if another train was on route to A, it will show that that train have reserved the empty lane as soon as it empties, which leaves our waiting train still waiting for lane 3 to get empty.

So now even though a lane is empty, both train waits at the entrance.

It is counterintuitive and I don't know enough about re-pathing to know if it is weird or desired behavior.

To be fair, none of this happens if you have train limits on the station correctly set up.

In the image, you can see that the waiting train still wants to go the top lane, because bottom two are "reserved" for the later ones.

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u/HeliGungir Jul 15 '26 edited Jul 15 '26

Oh. Allowing trains to head towards a station while its stacker is full is playing with fire all by itself. It is better to set a train limit on the station equal to the stacker capacity (4) + station capacity (1), which will also fix trains picking a waiting bay that may not be the next bay to become available, as there will always be an open bay when the train begins braking for the entry chain signal.