[REQUEST] Depot train prioritization based on cargo

[doktorstick]

Howdy, I have a feature request with depots. I'll frequently get trains with some left-over resource in it. It would be nice if depots, perhaps with an optional signal, could choose a train with leftover cargo to the corresponding provider.

For example, if I have two trains in a depot, one with some leftover iron ore and one with no cargo, and the "needs iron ore" request goes out, the depot system would first send the one with iron ore in it before the empty cargo. If a copper ore request went out, it would send the empty one before the iron ore one.

The priority is then:
* send train that has cargo matching resource type
* send empty
* send any train regardless of cargo

[Optera]

Not needed.
Use stations loading only requested items from design thread.

[Kamuchi]

Also if you have trains going back to the depot with left over items in their cargo, it's an indication you are requesting too many with the request threshold or the station needs a redesign to be able to offload faster or a second station.
Ran into this issue aswel and as a temp solution I added active providers for each wagon at the depot and then added a dedicated trash train (if * > 1000) to pick up stuff, advantage to a dedicated trash train is that you can put down a stop, add to the route and go on a building spree and dump all excess in it to be hauled back home

Then started a new save and made the MadZuri provider/requester station to offload L3-C10-L3 wagons while keeping it all balanced for LTN to remain happy with no stuck trains

[doktorstick]

Not needed.
Use stations loading only requested items from design thread.

It's not an issue of loading the wrong items. It's an issue of not unloading the entire inventory before the train leaves. See more below.

Also if you have trains going back to the depot with left over items in their cargo, it's an indication you are requesting too many with the request threshold or the station needs a redesign to be able to offload faster or a second station.

Yeah, that's part of the problem for sure. But I use LTN very early. I only have blue inserters. Also, because of the difficulties I challenge myself with, my power wanes at night time, causing slower inserter behavior. The net of it is that I cannot accurately predict when a train will leave, so LTN's configuration options leave me... wanting. There was another thread about similar--for lack of better description--config problems.

It also doesn't really appeal to me to have to run timings out-of-game to set a config option in-game to try to guesstimate the proper behavior. It's antithetical to the spirit of Factorio.

[Kamuchi]

Yeah, that's part of the problem for sure. But I use LTN very early. I only have blue inserters. Also, because of the difficulties I challenge myself with, my power wanes at night time, causing slower inserter behavior. The net of it is that I cannot accurately predict when a train will leave, so LTN's configuration options leave me... wanting. There was another thread about similar--for lack of better description--config problems.

It also doesn't really appeal to me to have to run timings out-of-game to set a config option in-game to try to guesstimate the proper behavior. It's antithetical to the spirit of Factorio.

C'mon

boop

Simplest I can make it without combinators or filters.
Use a GREEN wire from the LTN station OUTPUT (inner little red square) to the bottom belt reading thingy and set (T > 0). When an automatic train stops, the train id is sent to start letting items through.
Set the train station to send train contents and make sure to wire it to the YELLOW highlight as that is the actual station and wire it above the check if a train has arrived.

This will cut off the belt feed when you reached the number of items you requested,though it would give you some extra.
You could add another inserter with stack override of 1 to check if the train contents is higher then requested and remove it, but without filter inserters that will just be a pain with multiple items.
Rreading about the slower inserters at night, be careful not to request too many items then or the train will go past it's station/delivery timeout and another one will be dispatched.

I actually used this in the past, though combinators, to cut off those inline loaders you can't control and just add ups lag.

Bad idea working

[doktorstick]

Well, thanks. I'll try some of what you suggested there and report back. Cheers.