Train cannot path to station it is already at

Don't know how to use a machine? Looking for efficient setups? Stuck in a mission?
Post Reply
SilentOne13
Manual Inserter
Manual Inserter
Posts: 2
Joined: Wed Jan 17, 2024 3:35 pm
Contact:

Train cannot path to station it is already at

Post by SilentOne13 »

- I have two trains (1 cargo wagon, 2 locomotives) waiting and filling up on coal in the south (Coal Production) but we will only use one for this example.

- I have two outposts, one to the West (Coal Receiving West) and one to the North (Coal Receiving Central).
Coal Receiving West (Outpost).jpg
Coal Receiving West (Outpost).jpg (216.24 KiB) Viewed 357 times
- The outposts each send a "C" signal when coal is running low (less than 10k) at their locations (red wire, goes to coal production in the south). These stations are disabled when a "C" is not being sent (green wire, local).

- The trains are supposed to go to the North and West outposts when they read a "C" signal but "rest" at the coal production stations in the south when there is no call for coal.

- When the North outpost no longer needs coal, it is disabled, but this means the trains must "read" Coal Production twice (skipping the disabled outpost). The train reads the first one and goes to Coal Production. However, when the train skips the disabled station and reads the Coal Production again, it gets confused saying it has no path to it even though it is already there.
Inaccessible Stop.jpg
Inaccessible Stop.jpg (453.74 KiB) Viewed 357 times

If you go into the train orders:
Train Orders.jpg
Train Orders.jpg (81.16 KiB) Viewed 357 times
You can see it says "Both stops are inaccessible from current position, but if you try to add it as another stop, it claims 1 of 2 stops IS accessible from current position.
Stop is Accessible.jpg
Stop is Accessible.jpg (75.56 KiB) Viewed 357 times
The reason I have it setup like this is so that the train always comes back for a full load of cargo to rest before going to the stations that need it since train orders must be sequential. This way, outposts that don't need coal can be skipped. However, reading the same "production" station multiple times (skipping over disabled outposts) is leaving trains confused.

- I have noticed two things:
#1, when the train is trying to go from Production to Production and cannot find a path to the station it is already at (since the outpost is skipped as it is disabled), the train is not technically "at" the station as I tried setting a circuit signal at this moment to read the train contents but it wasn't able to send anything at that time.
#2, removing a signal on the track will permit the train to proceed as normal until it comes back and repeats the "no path" error again.

Now you may be thinking "well at this point it's using the other locomotive to go the opposite direction so that is the one trying to get to the same station". Yes, placing a second station on that side of the train with the same name fixes the problem, but if you remove that locomotive (making it a "one-way train") and only have the one locomotive on the right, the same locomotive throws the same "no path" error, looking for a station it is already at. There is no way to add more stations with the same name to fix this "one-way" train scenario.

Is there any way the game logic could be changed so that the train can check if it is already at the specified station and proceed from there?

Excellent game by the way.
Thank you!

User avatar
boskid
Factorio Staff
Factorio Staff
Posts: 2250
Joined: Thu Dec 14, 2017 6:56 pm
Contact:

Re: Train cannot path to station it is already at

Post by boskid »

Thanks for the report however this is Not a bug.

This behavior was explicitly requested by players to handle weird contraptions of "load long train at a sequence of same name train stops" which requires a train to explicitly reject going to the same train stop when going for a different schedule record.

BraveCaperCat
Long Handed Inserter
Long Handed Inserter
Posts: 50
Joined: Mon Jan 15, 2024 10:10 pm
Contact:

Re: Train cannot path to station it is already at

Post by BraveCaperCat »

SilentOne13 wrote:
Wed Jan 17, 2024 5:26 pm
- I have two trains (1 cargo wagon, 2 locomotives) waiting and filling up on coal in the south (Coal Production) but we will only use one for this example.

- I have two outposts, one to the West (Coal Receiving West) and one to the North (Coal Receiving Central).
Coal Receiving West (Outpost).jpg

- The outposts each send a "C" signal when coal is running low (less than 10k) at their locations (red wire, goes to coal production in the south). These stations are disabled when a "C" is not being sent (green wire, local).

- The trains are supposed to go to the North and West outposts when they read a "C" signal but "rest" at the coal production stations in the south when there is no call for coal.

- When the North outpost no longer needs coal, it is disabled, but this means the trains must "read" Coal Production twice (skipping the disabled outpost). The train reads the first one and goes to Coal Production. However, when the train skips the disabled station and reads the Coal Production again, it gets confused saying it has no path to it even though it is already there.
Inaccessible Stop.jpg


If you go into the train orders:
Train Orders.jpg

You can see it says "Both stops are inaccessible from current position, but if you try to add it as another stop, it claims 1 of 2 stops IS accessible from current position.
Stop is Accessible.jpg

The reason I have it setup like this is so that the train always comes back for a full load of cargo to rest before going to the stations that need it since train orders must be sequential. This way, outposts that don't need coal can be skipped. However, reading the same "production" station multiple times (skipping over disabled outposts) is leaving trains confused.

- I have noticed two things:
#1, when the train is trying to go from Production to Production and cannot find a path to the station it is already at (since the outpost is skipped as it is disabled), the train is not technically "at" the station as I tried setting a circuit signal at this moment to read the train contents but it wasn't able to send anything at that time.
#2, removing a signal on the track will permit the train to proceed as normal until it comes back and repeats the "no path" error again.

Now you may be thinking "well at this point it's using the other locomotive to go the opposite direction so that is the one trying to get to the same station". Yes, placing a second station on that side of the train with the same name fixes the problem, but if you remove that locomotive (making it a "one-way train") and only have the one locomotive on the right, the same locomotive throws the same "no path" error, looking for a station it is already at. There is no way to add more stations with the same name to fix this "one-way" train scenario.

Is there any way the game logic could be changed so that the train can check if it is already at the specified station and proceed from there?

Excellent game by the way.
Thank you!
It would be much easier for you once the expansion comes out, with it's changes to train schedules (Interrupt 1: when Train has Coal in it's Cargo Wagons, go to Coal Dropoff 1, Interrupt 2: when Train has Coal in it's Cargo Wagons, go to Coal Dropoff 2)
Plus you could have 1 train per station.

SilentOne13
Manual Inserter
Manual Inserter
Posts: 2
Joined: Wed Jan 17, 2024 3:35 pm
Contact:

Re: Train cannot path to station it is already at

Post by SilentOne13 »

Ok thanks for the explanation.

I know the interrupt functionality will be a great improvement. Can't wait!

Post Reply

Return to “Gameplay Help”