[Fixed 1.16][Improvement 1.15] Cars skipping nearest slot.

I use about 4 to 5 paint dries, like most people do, and the cars will bypass an open drier and queue up on one that is being used. Not sure if this is a bug but, I feel that this should be fixed as it is causing cars to back up. I’m using 1.06 and have this problem.

If there are several driers to choose from then that’s normal behavior… and should only result in a local queue which should only reach back to the branches… up to the point where the amount of dryers is enough to cope with the incoming cars.

But I agree that the logic for the path-finder is sub optimal in certain cases and could be improved on by Cliff.

Yes the logic for the path finding needs to be fixed. I feel that the cars should go to the closest station. In my layout they go to the farthest station and even if they go passed an empty drier station.

Thanks for the reply, I’m having fun playing and look forward to the updates and added content.


Hey folks,

At all this behavior is a bit annoying.

Did you ever try a slightly different layout as work around?
As soon as another conveyor tile is placed between the last crossing and the dryer all works well:


Kind regards

EDIT (2017-02-13)
Got some fresh K so best time to correct a misspelling. Sorry :*(

At 3-way branches I’m actually using symmetric splits most of the time… so basically the path to the entry points of assembly stations is always equally as long as seen from the branch… that way there is a 50 : 50 chance of taking either the left or the right path… therefore distributing a lot better (though not perfect if the assembly stations take unequal amounts of time due to different upgrades etc).

At 4-way crossings I’m doing the same as with 3-way… symmetric. Then there’s almost a 33.3 : 33.3 : 33.3 chance of the middle, the left or the right path being taken.

But what can I say… I played too much Factorio so I know the advantage of symmetric designs and that they behave a lot more deterministic… at the cost of increased space mostly.

Hey MeduSalem,

would you please post an example of such layout? (I’ld like to learn from others experiences :D)
The pictures from me are from an early game (1 painter > 2 dryer) and from a late game (at all but not on the picture 8 painter > 24 dryer).

If possible (and necessary) I also prefer to match 1 painter with 3 dryers. Because I want to have at least one tile of conveyor in front of the dryer (so there is a chance that the next vehicle is waiting when the actual one is done) it looks like this:

This works great for me even if there’s a backlock after the painting. So, I’m not sure if this is related to line design or really a bug which needs to be fixed.

Kind regards

I have a large number of dryers set up sequentially. I thought the cars would pass by a slot and if it was available take it then the next car behind would take the next and then if one slot was full skip it and continue. However cars are routinely skipping available slots and going further along. They are even creating a line at the final slot. The highlighted area has 27 dryers.You can see 5 lined up at the last dryer with 13 free dryers skipped. Plus a nother line of cars headed to the end.

It is not really a bug, but rather the pathfinding algorithm not working very efficiently.

On the longterm Cliff might have to improve it, but currently it is not really an issue that prevents people from playing because the traffic jam will only be locally (towards the end as you pointed out) and no matter how many slots you would add it would still happen at slot(s) that is the furthest away.

… Threads merged together …

I understand that but I was designing it this way so I would not have traffic jams. I am trying to create a smooth flow with no waiting and if cars don’t go into the first available slot that makes it extremely hard to be as efficient as possible. Once margins start to drop that becomes much more important.


As I said, the traffic jam is only locally. The only two reasons why margins drop are following:

  1. The traffic reaches so far back that one slot can’t output a car anymore.
  2. You have too many slots that are unused.

So what you have to do is only place so many slots that the “local traffic” jam causes all slots to be used, but also so that it doesn’t backlog to the output of a slot from the previous stage.

That makes it extremely hard to manage. There is no way for me to guess which routes would be taken so if I break it up into separate lanes with say 5 per lane I could still end up with traffic in unexpected places and still have the same problem.

I have a large factory with multiple export slots. in front of 2 of the slots I have 3 quality checks. The quality checks are closer to one slot than the other. You can see it circled in red in the screenshot. None of the cars leaving the quality checks goes to the nearest export slot. They all head to the one farther down the line. I would expect at the very least for a car to enter when it is empty even if ever car skipped it while another one was there.

Yes, this is a known bug relating to there not being a straight empty route before a slot, and one that’s on my list to fix. I know its annoying :frowning:

Sorry Cliff, should have realised this was the same issue.