I think train routing is subtly broken, but…

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Jürgen Erhard
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I think train routing is subtly broken, but…

Post by Jürgen Erhard »

Why does it do this? Or rather, why doesn't it take the lane that is advertised (intentionally) as open?

Both reach the same station.

The left lane that it decides is less good (but which has space for more than one train) already *has* six trains. The right lane has none. Thus… more red signals are bad? But what did the sixth train take this lane, just like the other five have?

ObOnTopic: how do I ensure trains take lane 2 *only* if lane 1 is full? That red signal (let's call it B) is therefore tied to the green one (let's call it A), with B being red as long as A is green.

(It's of course very likely not a bug, because whenever I think it is, it's "Working as intended" (which is a programmer euphemism for "bug/misfeature, we just hate to admit it"))
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TruePikachu
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Re: I think train routing is subtly broken, but…

Post by TruePikachu »

I do not see any explicit issue in this screenshot, but it would be a good idea to check the rest of the path between the green signal and the station, to ensure e.g. that no signals are facing the wrong way.

What happens if you put the train in manual, drive it to just before the green signal (so it hasn't passed it yet), and then set it back to automatic?

mergele
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Re: I think train routing is subtly broken, but…

Post by mergele »

Iirc the pathfinding happens actually rather rarely, so it might not have recalculated the path.

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TruePikachu
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Re: I think train routing is subtly broken, but…

Post by TruePikachu »

mergele wrote:
Thu Jan 02, 2020 9:29 pm
Iirc the pathfinding happens actually rather rarely, so it might not have recalculated the path.
The path is recalculated every 30 seconds while stopped at a chain signal, or every 5 seconds if there are multiple stops with the same name as the destination. The path is also recalculated just before the train starts braking for any signal. If the train didn't recalculate its path, it's a rare bug.

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Re: I think train routing is subtly broken, but…

Post by TruePikachu »

Just a note to everyone watching this thread, bug 79640 was recently opened which seems to possibly be related to this behaviour.

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