Rubidium wrote:

I've looked at the location where it left, ran the game for a while and couldn't see any trains going the wrong way.

However, looking at the station, leaving from the "normal" way is probably not what caused the train to go completely "wrong". I think it went to the side with the shorter platforms, and from there it needed to make a huge loop to get to the waypoint.

Basically, from the drop station it took the C branch via Lindean East then south of Dundon, passing Dunway North and then going over the bridge north east of Accdore South instead of diverging to Accdore Waypoint # 2.

If/when there are many trains waiting on the track towards Accdore Waypoint # 2 and not much is happening on the route via Accdore Waypoint # 3, then the pathfinder penalties might be stacked in such a way that the train goes a different way. For example, it considers the first 10 signals, and the occupation of tracks. These penalties could make the other route with the too short station a viable alternative.

The main problem is that there is not one set of pathfinder penalties or rules that makes every vehicle behave as the person that gave it orders envisions it. Currently we have a set that seems to cause fairly little trouble with pathfinding.

To properly figure out what happened in the instance of that train, we need a savegame that reproduces the misbehaviour. Without it, we cannot see how the pathfinder penalties were, and thus whether we can recommend a different set of penalties for your game.

Finally, you seem to be using custom builds of some sort which might also be messing with the pathfinder in some mysterious way. It is therefore important that the misbehaving train also misbehaves in a clean version of OpenTTD, but please state which version that is exactly.

This comment was imported from FlySpray: https://bugs.openttd.org/task/5993#comment13316

Rubidium closed the ticket.

Reason for closing: Not enough information

This comment was imported from FlySpray: https://bugs.openttd.org/task/5993

EthanG wrote:

Sorry for not replying, I thought I had. Thanks for the 10-signals hint, I've been keeping that in mind. I added waypoint orders for the train that had the problem, to direct it onto the A branch. You're right about the current pathfinder rules causing little trouble, there's a lot happening on this map but problems are quite rare.

About custom builds, I'll give the hg revision and date of pull on future reports.

This comment was imported from FlySpray: https://bugs.openttd.org/task/5993#comment13505