[1.1.30] Trains disobey chain signals

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DRY411S
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[1.1.30] Trains disobey chain signals

Post by DRY411S »

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Trains are leaving the stacker even though the route to their chosen station has red chain signals en-route. This is causing a deadlock.

The station has a train limit on it.
The ore unload station immediately due North of it, has the same name and the same train limit.
There are trains in the stacker that are targeting both stations.
The train that has disobeyed the chains has (I think) arrived after others that were patiently waiting their turn in the stacker.

How to reproduce

If you force the 'bad train' to go to collect ore instead, then you can see this behaviour repeated. It is reproducible. It can happen for both ore unload stations and the plate load station.

The cause seems to be unused station posts

Note on the screenshot, all the stations in the stacker. All have the same name but NONE are actually in use by any train on the map.
If I remove these stations from the stacker, this issue seems to go away.

I've attached a save game where this weird behaviour is happening.

Note: the screenshot shows that the ore unload stations have circuit control on them. This was me trying to stop what was happening, unsuccessfully. In the save game I have removed these circuits.
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Loewchen
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Re: [1.1.30] Trains disobey chain signals

Post by Loewchen »

I let it run for several minutes and no train ever disobeyed a chain signal.

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Re: [1.1.30] Trains disobey chain signals

Post by DRY411S »

I should add that in the save game, the signals at the top of the stacker are regular signals. Again, this was an unsuccessful attempt to fix this. The problem still occurs if they are chain signals (as the ought to be).

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Re: [1.1.30] Trains disobey chain signals

Post by DRY411S »

Loewchen wrote: ↑
Sat Apr 03, 2021 3:53 pm
I let it run for several minutes and no train ever disobeyed a chain signal.
Maybe I am using the wrong language/term. The trains should not leave the stacker if there are red chains on the way to their target destination right?

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Re: [1.1.30] Trains disobey chain signals

Post by SoShootMe »

DRY411S wrote: ↑
Sat Apr 03, 2021 3:54 pm
I should add that in the save game, the signals at the top of the stacker are regular signals. Again, this was an unsuccessful attempt to fix this. The problem still occurs if they are chain signals (as the ought to be).
You said the issue could be reproduced. Can you reproduce it starting from the save game you uploaded, or can you upload a save where you can reproduce it? Either way, how do you reproduce it (eg which train should be forced to fetch ore)?

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Re: [1.1.30] Trains disobey chain signals

Post by DRY411S »

SoShootMe wrote: ↑
Sat Apr 03, 2021 4:04 pm
DRY411S wrote: ↑
Sat Apr 03, 2021 3:54 pm
I should add that in the save game, the signals at the top of the stacker are regular signals. Again, this was an unsuccessful attempt to fix this. The problem still occurs if they are chain signals (as the ought to be).
You said the issue could be reproduced. Can you reproduce it starting from the save game you uploaded, or can you upload a save where you can reproduce it? Either way, how do you reproduce it (eg which train should be forced to fetch ore)?
The save game I uploaded has a train at a chain signal just past the stacker (as in screenshot).
I claim that the train should not have left the stacker because there are red chain signals along it's planned route.
If you tell that blocked train to go and collect some ore, and not deliver it, then (for me) very soon afterwards, another train in the stacker will leave the stacker even though a chain is blocking where it wants to go.

Lowchen says they cannot reproduce it, and has moved this to Gameplay Help. I can reproduce this. Happy to stream it if necessary. I really don't need Help.

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Re: [1.1.30] Trains disobey chain signals

Post by Loewchen »

DRY411S wrote: ↑
Sat Apr 03, 2021 3:56 pm
I am using the wrong language/term. The trains should not leave the stacker if there are red chains on the way to their target destination right?
That would be absurd, imagine if you had a 100000 track length route and a train would only start the journey if there is not a single closed chain signal anywhere on the path. In reality the train goes until it reaches a signal that does not let it pass.

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Re: [1.1.30] Trains disobey chain signals

Post by boskid »

I see no issues in that save file.

Train passed regular signal because next block was open and stopped at the chain signal. Everything works exactly as designed.

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Re: [1.1.30] Trains disobey chain signals

Post by Loewchen »

The setup locks up after a while because an ore train waits at the chain signal, while the ore trains in the stations cannot be fully unloaded because copper plates are full.
If you signal it so that trains only leave the holding bay if the complete path and station is free then this should work.

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Re: [1.1.30] Trains disobey chain signals

Post by DRY411S »

Loewchen wrote: ↑
Sat Apr 03, 2021 4:31 pm
If you signal it so that trains only leave the holding bay if the complete path and station is free then this should work.
But that's what I've done? The chains from the stacker are blue blue blue blue blue red red red (regular signal), yet the train leaves the stacker and stops at the first blue.

Nobody else using my save game upload sees this behaviour from the trains?

If I delete all the train stops in the stacker, then I don't see the behaviour anymore, the trains stay in the stacker as I would expect. It's a weird glitch for sure.

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Re: [1.1.30] Trains disobey chain signals

Post by SoShootMe »

DRY411S wrote: ↑
Sat Apr 03, 2021 3:54 pm
I should add that in the save game, the signals at the top of the stacker are regular signals. Again, this was an unsuccessful attempt to fix this. The problem still occurs if they are chain signals (as the ought to be).
I'm seeing expected behaviour with rail signals in the stacker, as in the save. They need to be chain signals to ensure the issue Loewchen described is prevented, but perhaps when you thought they were all chain signals, at least one was in fact a rail signal, hidden by a locomotive waiting to the east.

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Re: [1.1.30] Trains disobey chain signals

Post by DRY411S »

SoShootMe wrote: ↑
Sat Apr 03, 2021 4:47 pm
I'm seeing expected behaviour with rail signals in the stacker, as in the save. They need to be chain signals to ensure the issue Loewchen described is prevented, but perhaps when you thought they were all chain signals, at least one was in fact a rail signal, hidden by a locomotive waiting to the east.
No. I promise you. If I load the save that I have uploaded here, the EXACT save, you are all trying, with NO regular signals misplaced, I get the behaviour I describe in the OP. But none of you seem to see that behaviour. Then when I delete the train stops, the behaviour stops.

I'm off to do a complete clean install of the game to see if the issue disappears.

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Re: [1.1.30] Trains disobey chain signals

Post by Loewchen »

DRY411S wrote: ↑
Sat Apr 03, 2021 4:39 pm
But that's what I've done? The chains from the stacker are blue blue blue blue blue red red red (regular signal), yet the train leaves the stacker and stops at the first blue.
The save you provided does not have signaling that would prevent a train from leaving the holding bay without an available path to its targeted station. If you want to know why a setup with such signaling does not work, then post such a save file.

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Re: [1.1.30] Trains disobey chain signals

Post by DRY411S »

Sorry I'm confused now.

Are people trying the save game and NOT seeing the bahaviour (which is what I think you said in your first reply)? Or is everybody seeing the same behaviour that I have reported, and it's 'as expected'? If it is as expected, what changes do I need to make? From the stacker, it is chain (x6), regular, station. What needs to be different?

And why for me does the behaviour completely stop if I remove the station posts, with no further signal changes?

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Re: [1.1.30] Trains disobey chain signals

Post by boskid »

Signals in yellow circle are regular signals. If there are no trains in the rail block within the blue rectangle, all of those regular signals will show green and one train will pass. If you want the trains to not occupy the top rail block, you should consider it as being an "intersection" and standard rules will apply: "chain in" (signals in yellow circles should be chain signals).
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Re: [1.1.30] Trains disobey chain signals

Post by SoShootMe »

DRY411S wrote: ↑
Sat Apr 03, 2021 5:07 pm
Are people trying the save game and NOT seeing the bahaviour (which is what I think you said in your first reply)? Or is everybody seeing the same behaviour that I have reported, and it's 'as expected'?
The behaviour I see (after loading your save) is as I would expect. With rail (not chain) signals at the north of the stacker, trains will proceed to the chain signal where the highlighted train in your screenshot is, and (if necessary) wait there until they can reserve a path past a rail signal.

Replace the rail signals at the north of the stacker with chain signals, and the trains will be forced to wait there until they can reach one of the stops.
DRY411S wrote: ↑
Sat Apr 03, 2021 5:07 pm
And why for me does the behaviour completely stop if I remove the station posts, with no further signal changes?
I do not see any change in behaviour by removing the unused train stops in stacker (making no other changes after loading your save). This is also as I would expect.

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Re: [1.1.30] Trains disobey chain signals

Post by DRY411S »

SoShootMe wrote: ↑
Sat Apr 03, 2021 5:17 pm
DRY411S wrote: ↑
Sat Apr 03, 2021 5:07 pm
Are people trying the save game and NOT seeing the bahaviour (which is what I think you said in your first reply)? Or is everybody seeing the same behaviour that I have reported, and it's 'as expected'?
The behaviour I see (after loading your save) is as I would expect. With rail (not chain) signals at the north of the stacker, trains will proceed to the chain signal where the highlighted train in your screenshot is, and (if necessary) wait there until they can reserve a path past a rail signal.

Replace the rail signals at the north of the stacker with chain signals, and the trains will be forced to wait there until they can reach one of the stops.
DRY411S wrote: ↑
Sat Apr 03, 2021 5:07 pm
And why for me does the behaviour completely stop if I remove the station posts, with no further signal changes?
I do not see any change in behaviour by removing the unused train stops in stacker (making no other changes after loading your save). This is also as I would expect.
Thank you for clarifying that you are seeing what I describe. As you say, it is what you should expect because the save game I uploaded has got regular signals at the top of the stacker.

I believe that I know what has happened here.

When I saw this behaviour in v1.1.21, the signals at the top of the stacker were chain signals (as they should be and that's what I ALWAYS normally do), I was seeing what I describe. I am pretty sure that the screenshot in the OP taken in v1.1.21 has chain signals.

I was so flummoxed as to what was causing it, I was trying everything to fix it. But it had to be abug.

If I was going to bug report it then I should make sure I had the most up to date version, I upgraded from v1.1.21 to v1.1.30, loaded the save and STIIL saw the same behaviour I'd seen in v1.1.21.

Or I thought that I did, so I bug reported it. What I was actually seeing though in v1.1.30 was expected behaviour because of the 'wrong' signals in my save file.

Changing the signals to what they were in the first place, the problem has gone away in v1.1.30.

I can only conclude that this was a bug in v1.1.21, (WITH chain signals and train stops, which disappeared when I removed the train stops) but is NOT in v1.1.30 (with or without train stops). I discussed what I was seeing in v1.1.21 before posting the report in the official Discord. https://discord.com/channels/1396775903 ... 8257903646

Moderators, please close. I'm still irked that this got moved to Gameplay Help, I really did see what I describe, but NOT in v1.1.30, it was v1.1.21.

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Re: [1.1.30] Trains disobey chain signals

Post by DRY411S »

Final update. I found an old save where the stacker was the way I designed it with chains at the top, and the issue was occurring.

I'm very very (and once again very) embarrassed to say that the cause was ghost chain signals in 2 of the stacker lanes! :oops: :oops: :oops:

So no bug, not even in v1.1.21.

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