old LTN discussion thread

[Anson]

I confused myself since it defaults to comparator = >.

easy fix : no fix and no update needed because of the default.
but it should be adjusted anyway for the next version since they might someday decide to change the default ...

[Optera]

I confused myself since it defaults to comparator = >.

easy fix : no fix and no update needed because of the default.
but it should be adjusted anyway for the next version since they might someday decide to change the default ...

Done already.
Let me know how well 0.6 holds up in your usage scenarios.

[Anson]

Let me know how well 0.6 holds up in your usage scenarios.

just tested on my old request-testmap, and it worked pretty well, doing proper round robin.

debugging my setup

then i setup the two arithmetic combinators to round down the output to a multiple of the desired minsize, and it mostly worked. only "mostly" because it sent no trains below 2000 (minsize=2000, combinators dividing by 2000 and then multiplying by 2000), and it sent one train above 2000. but when that train started to be loaded, another train was sent immediately to get something like 1800 which of course were not available yet.

as far as i could see, this effect probably was not a bug of the mod, but a timing problem of the two combinators, delaying signals for up to 2 or 3 ticks, in combination with unknown delay for the mod to calculate the current sum of station, reserved amounts and train. probably also related to the station dropping below the threshold and then rising back from 0 to 2000, which the mod saw as having available another (almost) 2000 items, and thus immediately sent a second train to get 1880 or some amount like that. when the first train had finished loading, only 400+ were left and the second train waited some time ...

when i subtracted (on the input of the first combinator) some number like 150 (assuming it was related to the inserters and their bonus, 6*12 = 72, or double that 144), the problem seemed to be gone, but probably not for long. i need to test more to get better values, see whether this also happens between 4000 and 4050, etc, and generally understand what is happening :-)

debugging a running system with varying values is a "joy" :-) :-(

all this was not about the mod,
but about my setup that shall avoid low amounts of delivery while besteffort is true.
-----
now something about the mod:
to get more info, i used the new option to increase the protocol level in the config (very nice), but was immediately flooded with two messages per second that there was no station supplying iron and copper. although i wanted more info, this was a bit too much too often, and also too loud (one beep per second while i tried to concentrate on debugging my setup). i also needed to pause the game to read the important messages between those spammed lines. at least those lines provided me with some timing, that everything between them happened during the same second :-)
would it be possible to somehow suppress such duplicate warnings (at least for some time like 30 seconds), either at loglevel 3 or by introducing a loglevel 2.5 ?
-----
to remove some ugly paint from my wagons, i had picked them up and set them down again, and thus they were unregistered trains for this mod. maybe a warning should be included somewhere, eg on the OP of this thread, that every new train must be sent to the depot, even if it is already waiting at the depot and only unregistered because the wagons have changed, and it is good enough to click on "send to station (depot)" even when the train doesn't move.
-----
because of this problem i had only one registered train,
and i finally got some useful info from loglevel 3,
and that looks like a real bug (or some really strange internals),
but the following probably is a bit too long, difficult, and uninteresting to the "general public",
thus hidden in a spoiler :-)

lots of detail

because of this effect, i had only one train trying to service my supply station and 3 requesters. the good thing is that it cycled through them (proper round robin), but the bad thing are some problems in the messages :

• no station supplying copper, no station supplying iron (the first second)
• train arrived at copper field
  (immediately followed by:)
• added new order 1 copper field >> smeltery1drop: 2000 in 40 stacks
  (why ? there were less than 4000: after loading 2000 and producing more ore,
  the train left in the end with less than 1500 remaining in the chests)
• no station supplying iron (the second second)
• no train to transport 40 stacks found in depot (correct)
• added new order 1 copper field >> smeltery3drop: 2000 in 40 stacks
  (another order for 2000 (see above)?)
• added new order 1 copper field >> smeltery2drop: 2000 in 40 stacks
  (another order for 2000 (see above), and even during the same second?)
• added new order 1 copper field >> smeltery1drop: 1784 in 40 stacks
  (another order for 1784 (see above), and even during the same second?)
  (at least round robin works :-)
  (and why only 1784 now?)
• no station supplying iron (the third second)
  (with another set of three new orders for ever decreasing amounts)
• no train to transport 36 stacks found in depot (correct)
• added new order 1 copper field >> smeltery3drop: 1784 in 36 stacks
• added new order 1 copper field >> smeltery2drop: 1784 in 36 stacks
• added new order 1 copper field >> smeltery1drop: 1640 in 33 stacks
• (and so on, one "no train" and three new orders per second: 1496 in 30, 1352 in 28)
• (starting here, the train probably had loaded enough to get the available amount below 2000)
  (even with 2000 shown, LTN should have known that is less because of reservations)
• (from here on, only messages about missing iron and copper)

edit: my comments were written with italics, but the forum seems to change the fontsize for each attribute used, when bold, italics and/or underline are used inside a spoiler, and worst if all three are used.

round robin seems to work now when besteffort is on, but
- why is always a "new order 1" created ?
- why does it create three new orders per second ?
- why does it only report one missing train although it reported three new orders ?
- why are the amounts and thus the stacksize decreasing ?
- why does it issue new orders at all when the (rounded) amount was 2000 at first (with lots of ore reserved)
and until the amount (input to the lamp) dropped to 0 ?

maybe the strange effects when debugging my setup (in the other spoiler) were related to these effects too.
a lot more testing is needed ...

but first the results from a second test, where the copper field had 4500 ore when the only train left the smeltery towards the depot:

• no station supplying copper, no station supplying iron (the first second)
• train left smeltery drop
  (immediately followed by:)
• added new order 1 copper field >> smeltery1drop: 2000 in 40 stacks
• (one order during the first second, ok)
• no station supplying iron (the second second)
• no train to transport 40 stacks found in depot (correct)
• added new order 1 copper field >> smeltery3drop: 2000 in 40 stacks
• added new order 1 copper field >> smeltery2drop: 2000 in 40 stacks
• added new order 1 copper field >> smeltery1drop: 4000 in 80 stacks
  (immediately three new orders after no train was found, strange)
  (after one order for 2000 to each drop, now orders for 4000, even stranger)
• no station supplying iron (the third second)
• (starting from this third second, once per second constant amounts:
  always "no train for 80 stacks" and three orders for 4000 in 80 stacks)
• (continues until the train arrives at depot, and immediately the train is sent for delivery)
• (from now on repeating messages for "no train" and three orders for 2000)
• (continues until the train arrives at pickup when there is 5800 ore)
• (during the second when the train arrives:)
• no train for 40 stacks
• new order for ore field to smeltery 2 drop: 2000 in 40 stacks
• new order for ore field to smeltery 1 drop: 2000 in 40 stacks
• train arrived at copper field
• new order for ore field to smeltery 3 drop: 3936 in 79 stacks
  (i almost give up trying to understand this)
• (and so on, one "no train" and three new orders per second: 3792 in 76, 3576 in 72, ...)
• (continues until the train leaves from pickup when there is 5030+ ore)
• (during the second when the train leaves:)
• no train for 43 stacks
• new order for ore field to smeltery 2 drop: 2136 in 43 stacks
• new order for ore field to smeltery 1 drop: 2136 in 43 stacks
• train left copper field
• new order for ore field to smeltery 3 drop: 2000 in 40 stacks
• (starting from this second, once per second constant amounts:
  always "no train for 40 stacks" and three orders for 2000 in 40 stacks)
• (after station fills to 6000+, once per second constant amounts:
  always "no train for 80 stacks" and three orders for 4000 in 80 stacks)
• (after train leaves smeltery, once per second constant amounts:
  always "no train for 120 stacks" and three orders for 6000 in 120 stacks)
• (as soon as the train arrives at pickup again, now with 8000+, again decreasing amounts:
  always "no train" and three orders for 7920, 7716, 7572, 7416, 7272, ...)
• (ore drops below 8000, but the sequence continues: 5068, 4924, 4768, 4624, 4480, 4276, 4132)
• (after the train leaves the station, now again constant 4000 in 80)

the decreasing sequences seem to be in multiples of 72, which is the capacity of six inserters. but the sequence is decreasing quite linearly (2 cycles per second for 144 ore), thus probably independent of some other inserters filling up the chests, and the numbers are only based on some stored amount, the reservations, and the current train contents.

without studying the sourcecode, i have to give up for today.

[doe]

How do i stop my trains going to a provider station below what the minimum pickup is? for example i got -8k as min amount, and it send like 5-6 trains to get varied low amounts even though the prov does not have 8k yet. they go to get like 260 / 100 / 190 / 240 etc etc

i done something wrong with setup or i need to do something to stop this happening?

any help appreciated.

[Optera]

How do i stop my trains going to a provider station below what the minimum pickup is? for example i got -8k as min amount, and it send like 5-6 trains to get varied low amounts even though the prov does not have 8k yet. they go to get like 260 / 100 / 190 / 240 etc etc

i done something wrong with setup or i need to do something to stop this happening?

any help appreciated.

use_Best_Effort = false

...

Thanks for testing. Next time please include the logfile at loglevel 4, so i can see in detail what each station has in stock and calculates.

Why is the math off?
When a train is parked at a station it changes calculating item count from value stored in delivery to train inventory. I probably should get rid of that old fluff as well, use the constant delivery amount and update that once a train left a provider.

At debug level 3 and 4 I run into a limitation of the console where it only prints x messages per tick and randomly swallows some.
Using log_output = "log" doesn't seem to have that limit.
That's info normal users don't need, so in order to not overwhelm them I never said anything about it.

Why are orders generated when there are no trains available?
In short I only know how long the train should be once i have a provider.

Logic goes like this

Code: Select all

for request in requests do
  find providers
  limit request count to provider count
  merge orders
  find train
  if train found then
    limit count to fit in train
    save order to active deliveries
    break
  end
end

Changing parked trains
Factorio has the nasty habit of recreating the whole train when carriages are added/removed without firing an event. The newly created trains used to be parked at a station in automatic mode, but as there's no event the station never recognized them.
My fix for that makes trains to switch to manual mode whenever you change them. Seems like I forgot to mention this in OP.

[Optera]

0.6.1/0.6.2: Fixed 2 bugs with how provided item reservations are updated.
- during loading reserved amounts are updated with train inventory
- after leaving the provider the requester gets the actual inventory added
- reservations of a delivery no longer exist once a train finished loading

Some of the odd behavior reported in earlier posts, like trains not seeing items available in the provider, was probably related to these two bugs.

[doe]

Installed your latest release, put a train down and sent to depot, when it reached depot i get this error:

Error while running event on_tick (ID 0)
__LogisticTrainNetwork__/control.lua:224: attempt to concatenate field 'from' (a nil value)

Then game crashed, happened 2 times now.

Only thing i did was change best effort from true to false.

[Optera]

Installed your latest release, put a train down and sent to depot, when it reached depot i get this error:

Error while running event on_tick (ID 0)
__LogisticTrainNetwork__/control.lua:224: attempt to concatenate field 'from' (a nil value)

Then game crashed, happened 2 times now.

Only thing i did was change best effort from true to false.

Thanks for reporting.
I really should stop coding when tired... Those "brilliant" ideas I get when tired always come back to bite me.

[doe]

Installed your latest release, put a train down and sent to depot, when it reached depot i get this error:

Error while running event on_tick (ID 0)
__LogisticTrainNetwork__/control.lua:224: attempt to concatenate field 'from' (a nil value)

Then game crashed, happened 2 times now.

Only thing i did was change best effort from true to false.

Thanks for reporting.
I really should stop coding when tired... Those "brilliant" ideas I get when tired always come back to bite me.

I seen that you released another version. Unfortunately i got exact same error and crash.

[Optera]

I seen that you released another version. Unfortunately i got exact same error and crash.

You could either stop all trains and pick them up or wait until the faulty deliveries time out.
Loading to before any train left a provider under 0.6.2 would also work.

[Optera]

Spread stop updates over update_interval. With this change Micro stutters when using several hundred LTN-stops should be gone now.

[JREwing]

Hello, thank you for a really useful mod.

I have a tip for using and a Nice to have wish.

Iam feeding station with requests generated by circuit with histeresis. Some stations are not reading chests at all. I feed signal from Roboport to hysteresis circuit, and if comodity is below limit (eg. less then 10k of iron plates), it sends a signal (-6k of iron plates) to the station. With Station Minimum delivery size at 2k. And keep sending this signal until amount in network reach higher limit (eg. 30k of iron plates). Then stop sending at all. It always hauling full trains (or maximum what sending station can provide, but not less than 2k).

And Nice-to-have feature would be a Strict size of train signal. I have infrastrucure designed for one size of trains but I would like to use service delivery trains (with one cargo wagon) to haul amunition, repair kits, logistic and repair bots etc. But I want use those small trains for only this job and no other, even if minimum delivery size is lower then capacity of this train. Because loading station could have that amount on position different from the first wagon. Or some requsting station could empty the second locomotive (reverse) fuel, if match with hauling cargo.
I would like to have strict orders for trains, which stations are for 5 cart trains only (and no longer or shorter are allowed), which stations are for 10 cart trains only (and no longer or shorter are allowed) and which stations are for 3 cart trains only (and no longer or shorter are allowed).

[Optera]

Hello, thank you for a really useful mod.

I have a tip for using and a Nice to have wish.

Iam feeding station with requests generated by circuit with histeresis. Some stations are not reading chests at all. I feed signal from Roboport to hysteresis circuit, and if comodity is below limit (eg. less then 10k of iron plates), it sends a signal (-6k of iron plates) to the station. With Station Minimum delivery size at 2k. And keep sending this signal until amount in network reach higher limit (eg. 30k of iron plates). Then stop sending at all. It always hauling full trains (or maximum what sending station can provide, but not less than 2k).

You know you could simply turn off best effort?

And Nice-to-have feature would be a Strict size of train signal. I have infrastrucure designed for one size of trains but I would like to use service delivery trains (with one cargo wagon) to haul amunition, repair kits, logistic and repair bots etc. But I want use those small trains for only this job and no other, even if minimum delivery size is lower then capacity of this train. Because loading station could have that amount on position different from the first wagon. Or some requsting station could empty the second locomotive (reverse) fuel, if match with hauling cargo.
I would like to have strict orders for trains, which stations are for 5 cart trains only (and no longer or shorter are allowed), which stations are for 10 cart trains only (and no longer or shorter are allowed) and which stations are for 3 cart trains only (and no longer or shorter are allowed).

I probably will add a minimum train length signal for convenience. You can get your exact 10 carriages by setting min and max to 10.

[JREwing]

You know you could simply turn off best effort?

Yes, I know. Iam using only that option. But I like hysteresis idea. Start hauling under 10k, and stops after reachin 30k. When Iam feeding the content (chest or logisting network) directly to the station, mod substract amount in chests from needed amount. So some trains may not be full. In my situation, trains are always full .

I probably will add a minimum train length signal for convenience. You can get your exact 10 carriages by setting min and max to 10.

That would be really nice feature.

Once again, very usefull mod.

[Optera]

You know you could simply turn off best effort?

Yes, I know. Iam using only that option. But I like hysteresis idea. Start hauling under 10k, and stops after reachin 30k. When Iam feeding the content (chest or logisting network) directly to the station, mod substract amount in chests from needed amount. So some trains may not be full. In my situation, trains are always full .

Any requester can be set to minimum shipment size >= train inventory size to achieve the same effect of your hysteresis.

With Best Effort on if your provider doesn't have enough to fill a train it will ship what's available. A hysteresis at the requester does nothing to prevent that, you would need to have it at the providers.

[Optera]

Updated the demo map in OP with stations showcasing a Provider & Requester using a smart loader with counter and a station for iron/copper loading able to unload items inserters held on to.

[Anson]

Any requester can be set to minimum shipment size >= train inventory size to achieve the same effect of your hysteresis.

how would that be done ?
can you please give us the values for signals at provider and requester to achieve this:
- no transports until requester has less than 10k ore
- when transports start, they are done with 2k delivery size
- transports continue until there are 30k ore
- transports don't stop when (after a few transports) the amount is back between 10k and 30k

although i probably would prefer a more steady flow (instead of peaks which might cause jams when several trains want to load and unload at the same time), i like the idea of setting up additional circuits to tend to special requirements (eg smelting batches of lots of copper and then lots of iron, instead of switching between the two all the time).

the min train length and max train length will be really nice.
(i had suggested that already myself :-)
an alternative could be to specify exact patterns (bitmasks) for engines and wagons, but that would probably be much too complicated to implement, to understand, and to use, and still not include all details that might be useful, eg not knowing the direction of the engines. parameters for min and max length together with specific lengths of trains should achieve good results already.

suggestion - refueling stations and stackers in front of depots

a useful addition might be to have refueling stations. they wouldn't have to be as variable as those from SmartTrains, but i would like to have them separate from the depot to avoid the need to build one depot signal and all the refueling logistics at each waiting space in big depot stackers. trains simply could start at a depot, get their orders (pickup at provider and drop at requester), and then finish their route at a refueling station (if available; could be marked with a logic signal, similar to depots). after refueling they would return to the depot station. this also could allow to have only a single refueling station (or one for each train length), then a giant stacker (without any train signals, etc), and finally only one depot (maybe with a few lanes to allow faster leaving after getting orders). if trains start at the depot and end their route at the refueling station, there would be no problem with orders timing out while slowly returning home, or waiting in a stacker in front of a depot.

suggestion - LTN already before blue science

another suggestion to make the mod usable for my current map:
please reduce the research requirements for LTN, to no longer need blue science (oil industry, plastic, red circuits, etc).
SmartTrains only require (2 red, 1 green) x70 @20 seconds, while you require (1 red, 1 green, 1 blue) x150 @30 seconds. having a bit higher requirements in number of science packs and time is ok with me, for the service that the mod provides, and at first sight the requirement of blue science for LTN matches the requirement of blue science for logistical chests. but in contrast to LTN, the bots themselves require oil industry (and plastic, and red circuits, and lubricant, and electric motors, and flight, etc) and thus it would be useless to allow logistical chests before people are able to setup a logistical network with robots. the use of trains is possible a lot earlier than bots and requires none of the other oily requirements. using trains also lacks the ability to finetune deliveries between any pair of assemblers.

the requirement of blue science can delay use of LTN quite a bit. getting some oil industry set up can take many dozens of hours when playing with other mods that make the game more difficult, eg angels and bobs :-) I'm still working on setting up basic smelting to get enough iron/copper and also some other ore, setting up a greenhouse farm since there is limited coal, etc, and thus i am quite far from setting up oil industry or blue science. but i alreday have to start using trains to get several different ores, wood, etc in correct proportions. and i even need trains to transport oil and gas to my base for learning how to setup an oil factory :-)

of course it is possible to cheat and edit the values of research, other requirements, or even use creative mode to cheat instant research, but i would prefer to have "vanilla LTN" be usable already a short while after all other train research (including signals=smarttrains, farl, shuttle, and some other mods that support trains) and a long while before the logistical networks with bots.

[Optera]

Any requester can be set to minimum shipment size >= train inventory size to achieve the same effect of your hysteresis.

how would that be done ?
can you please give us the values for signals at provider and requester to achieve this:
- no transports until requester has less than 10k ore
- when transports start, they are done with 2k delivery size
- transports continue until there are 30k ore
- transports don't stop when (after a few transports) the amount is back between 10k and 30k

although i probably would prefer a more steady flow (instead of peaks which might cause jams when several trains want to load and unload at the same time), i like the idea of setting up additional circuits to tend to special requirements (eg smelting batches of lots of copper and then lots of iron, instead of switching between the two all the time).

best effort = true
item = -30k
min shipment size = 20k

Will start a 20k order when item is lower than 10k. Best Effort will split the order in multiple shipments filling up all but the last train.

the min train length and max train length will be really nice.
(i had suggested that already myself
an alternative could be to specify exact patterns (bitmasks) for engines and wagons, but that would probably be much too complicated to implement, to understand, and to use, and still not include all details that might be useful, eg not knowing the direction of the engines. parameters for min and max length together with specific lengths of trains should achieve good results already.

An encoded signal for valid train compositions. I like that, but I wonder who even makes use of the current encoded composition signal?
Players seem to struggle coming up with stations that don't lock themselves with inserters holding on to items they couldn't insert. Feeding a binary encoded signal for valid trains is way above the combinator knowledge of most players.

suggestion - refueling stations and stackers in front of depots

a useful addition might be to have refueling stations. they wouldn't have to be as variable as those from SmartTrains, but i would like to have them separate from the depot to avoid the need to build one depot signal and all the refueling logistics at each waiting space in big depot stackers. trains simply could start at a depot, get their orders (pickup at provider and drop at requester), and then finish their route at a refueling station (if available; could be marked with a logic signal, similar to depots). after refueling they would return to the depot station. this also could allow to have only a single refueling station (or one for each train length), then a giant stacker (without any train signals, etc), and finally only one depot (maybe with a few lanes to allow faster leaving after getting orders). if trains start at the depot and end their route at the refueling station, there would be no problem with orders timing out while slowly returning home, or waiting in a stacker in front of a depot.

By outputing the encoded train composition LTN already allows for a more versatile and complex refueling system than smart trains.
I can see how a single refueling station would be less effort than having one at every depot.
My reasoning against dedicated refueling is this. Most networks need to remove left over items from trains somewhere. Best place to do that is the depot as all trains will go there. That means you end up with a unloading mechanism at every depot so it's just a matter of adding some more inserters and chests to add a refueling system.

Having dedicated refueling station(s) begs a lot of questions:

• Is this even a feature that will be used by a majority of players?
• Is it really less effort to ensure all possible stations and depots are reachable from the refueling station than stamping down some chests and inserters in existing depots?
• How would LTN ever know which refueling station to use?
• Are we back to using backer names and allow only one specific naming scheme for for refueling across all possible forces?

Why build a stacker in front of the depot? Just plant a LTN-stop at every stacker rail.

suggestion - LTN already before blue science

another suggestion to make the mod usable for my current map:
please reduce the research requirements for LTN, to no longer need blue science (oil industry, plastic, red circuits, etc).
SmartTrains only require (2 red, 1 green) x70 @20 seconds, while you require (1 red, 1 green, 1 blue) x150 @30 seconds. having a bit higher requirements in number of science packs and time is ok with me, for the service that the mod provides, and at first sight the requirement of blue science for LTN matches the requirement of blue science for logistical chests. but in contrast to LTN, the bots themselves require oil industry (and plastic, and red circuits, and lubricant, and electric motors, and flight, etc) and thus it would be useless to allow logistical chests before people are able to setup a logistical network with robots. the use of trains is possible a lot earlier than bots and requires none of the other oily requirements. using trains also lacks the ability to finetune deliveries between any pair of assemblers.

the requirement of blue science can delay use of LTN quite a bit. getting some oil industry set up can take many dozens of hours when playing with other mods that make the game more difficult, eg angels and bobs I'm still working on setting up basic smelting to get enough iron/copper and also some other ore, setting up a greenhouse farm since there is limited coal, etc, and thus i am quite far from setting up oil industry or blue science. but i alreday have to start using trains to get several different ores, wood, etc in correct proportions. and i even need trains to transport oil and gas to my base for learning how to setup an oil factory

of course it is possible to cheat and edit the values of research, other requirements, or even use creative mode to cheat instant research, but i would prefer to have "vanilla LTN" be usable already a short while after all other train research (including signals=smarttrains, farl, shuttle, and some other mods that support trains) and a long while before the logistical networks with bots.

Thanks for reminding me. I think I said I'd move it to a pure red/green tech, but somehow forgot about that. It will use a lot of red/greens and while at it i might also add some of bobs science requirements if you use that.

[Optera]

As requested 0.8.0 has Minimum Train length added as signal.
Be careful to not lock a station down by having impossible Minimum Train Length, Maximum Train Length, Minimum Delivery Size combinations
I also changed the tech to need 300 red/green sci packs instead of 150 red/green/blue.

[steinio]

Hello,

as i was one of the people who burned for this mod instead of some combinator contraptions i now tried to play with it and setted up a simple coal delivery route.
It works plently.

Now i want to set up a liquid route for Py's Creosote.
My depot has two logistic stops called Depot for solids and Depot for liquids and i scheduled the trains for each station.

How can i different if the provider/requester station needs a liquid or a solid train?

Greetings steinio