Age old question: "Load until full or next train arrives" function?

[paulcobbaut]

I like this question!

Expanded: when a station has multiple platforms that are all occupied, and a new train arrives, then one train should leave the station. Which one would ideally be a choice of 'the fullest' or 'of the same group' or 'the one that is there the longest time'...

[odisseus]

There are work-arounds for these issues, feasible even in the unmodifed game.

A self-regulating network ensures that the number of trains that arrive at the station is exactly sufficient to take all the supplied cargo. The situation when multiple trains are queued for loading just won't occur.

An overflow depot hides the queue away so that the waiting trains don't take space on the tracks. This solution doesn't eliminate the queues, but it's much more flexible than SRNW, and much easier to set up.

[testwater]

I appreciate your suggested workarounds, Odisseus.

I've already been using the depots to tuck away waiting trains, as that is the most reasonable solution I've found that doesn't involve perpetual micromanagement, but still I'm here in hopes of something less cheesy.

I had not yet come across the SRNW idea. I'll have to read about it. Thank you.

[Michpi]

You can use counters and conditional orders for this

[+] Spoiler

1.jpg (282.34 KiB) Viewed 376 times

[paulcobbaut]

So I tried this counter...

Why are the trains not leaving the station?
The counter is named 'gogogo'. The counter is increased when a train passes the signal with blue arrow, and the counter is decreased when a train passes the pink arrow signal. This works.

Now I thought a train would 'jump to order 4' when the counter is above 2. But they just sit there in the station. (All trains have shared orders.)

What am I missing?
The goal is to keep the trains loading in the station, until a third train arrives, then one of them should leave. (So the pink signal will need to be set at every station exit later on.)

EDIT: Removing the 'full load any cargo' makes them all leave at the counter threshold. Ideally only one of them should leave.

openttd counters Screenshot_2026-05-28_19-34-36.png

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[paulcobbaut]

Found a solution, using a counter as a boolean.

Thank you for the hint on counters!

openttd counters Screenshot_2026-05-28_22-37-41.png

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[Michpi]

Found a solution, using a counter as a boolean.

I may be mistaken, but as far as I understand, in your case, the full train will not leave the station until the third train arrives.

[paulcobbaut]

Found a solution, using a counter as a boolean.

I may be mistaken, but as far as I understand, in your case, the full train will not leave the station until the third train arrives.

Adding a check at the beginning for 100 percent load seems to work. Like in this picture.

train.png

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