Vehicles prefer one lane over the over for no apparent reason

[WildQuoll]

There seems to be an issue in the modified path-finding that comes with TMPE, which affects roads with 2 or more lanes in one direction.

On some junctions, it seems all vehicles prefer to enter the lane closer to them, regardless of which lane they need to be in at the next junction (see attached pictures).

This doesn't happen with the vanilla path-finding, where vehicles generally enter whichever lane they need to be right at the start.

Some examples below:

Note: No lane connectors nor any of the optional 'advanced AI' features are involved.

Please let me know if you need any additional information.

[CosignCosine]

In some countries, it is illegal to make the second type of turn (as it interferes with other rights of way), so it was most likely banned in the updated pathfinding for that reason. It also speeds up traffic this way (vehicles aren't crossing paths with each other).

[originalfoo]

I think there's two distinct issues here:

1. Known issue with DLS (see: Cars All Choose the Same Lane Causing Congestion #263 - Per vehicle DLS randomisation)
   • Temporary workaround: Set DLS slider to less than 50%.
2. Pathfinder is coded in such a way to avoid crossing too many lanes when entering a road (basically what @CosignCosine said in the comment above)
   • We're pondering some sort of 'regional settings' to handle that sort of thing

(@FireController1847 can you remember where the regional settings were being discussed?)

[WildQuoll]

Thanks for the replies.

I'm not using DLS at all, so I don't think the 1st issue applies here, but the 2nd point does seem to explain it.

Unfortunately, in my observation the current behaviour slows down the flow of traffic in some cases (since vehicles queue in a single lane, rather than multiple). I would have though that no extra cost for any lane when turning at junctions and some extra cost for switching lanes outside of junctions, would work just fine.

[originalfoo]

I would have though that no extra cost for any lane when turning at junctions and some extra cost for switching lanes outside of junctions, would work just fine.

It would, and in fact we already do that in some places - like dead-end (cul-de-sac) segments on wide roads. Problem is that if we did it on junctions lots of people would start complaining because as mentioned earlier it's illegal in many countries to do that. Hence us pondering something relating to 'regional settings'.

We could potentially add a setting to global config that allows it to be toggled? (previous commit ref, I think, is: 0cb90e3 with background infos in #101)

[WildQuoll]

OK, good to know it's being considered. Looking forward to such option.

[FireController1847]

@aubergine10 In regards to the regional settings, I believe we had only discussed it within the Discord and did not make an actual issue for it.

@WildQuoll Take a look at this, for your second image. Just some resources that might help you understand why it was developed this way. Hopefully like aubergine10 said, we'll add regional settings that will allow things like this to be toggled. Funnily enough, I actually made an issue complaining about the exact opposite happening haha.

[FireController1847]

My apologies but with my recent increase in real life activities and my lack of participation in TM:PE in recent months, I think this issue would be better suited to someone else. If it's still around when I come back I'd look forward to fixing it, but for now I'm going to unassign myself. Sorry!