Trains FIFO suggestion

varundevan · Post by **varundevan** » Sat Oct 10, 2020 1:04 pm

Hi,

WHAT

To make trains to follow First in First out for in the junction or at any waiting signal.

HOW

The trains are not somehow following FIFO even if we wanted to, and of course there are some decent complicated ways to achieve that via circuits.
I have an idea to make each train to have an internal clock, and the clock would start ticking when the train stops at a signal.

so, that the train with highest waiting time will be given the highest priority to leave the junction or leave the spot that is currently waiting.

Post by **ssilk** » Mon Oct 12, 2020 4:55 am

Why do you mean that the order of trains is somehow important?

Post by **boskid** » Mon Oct 12, 2020 8:15 am

Nope.

When a train arrives at signal it is the only train to arrive at that given signal, so what you are most likely requesting is if a train cannot reserve a block it should queue as first for the reservation. This would work only in case of a rail signals, but in case of rail chain signals it would require train to be put in queue of multiple rail blocks, even when some of them are empty at that moment. There is no partial reservation (reserve only one block of a chain signal section) or forced reservation revokation (the rail block is reserved but the train was unable to reserve all rail blocks, lets cancel its reservation so i can pass as i have different path through the crosssection). By implementing that, it could happen that a train that can safely pass the crossection as its path is "guarded" by another train going in the same direction but on the adjacent rail - would have to stop at a rail signal that would be green and there would be no clear feedback as to why the train is waiting at the signal.

: 90247.png (579.83 KiB) Viewed 1524 times

varundevan · Post by **varundevan** » Mon Oct 12, 2020 6:56 pm

ssilk wrote: ↑
Mon Oct 12, 2020 4:55 am
Why do you mean that the order of trains is somehow important?

because it feels right

trains from coming from far away are coming and leaving the junction where as a near by train trying to cross the same junction end up waiting for eternity.

varundevan · Post by **varundevan** » Mon Oct 12, 2020 6:59 pm

boskid wrote: ↑
Mon Oct 12, 2020 8:15 am
Nope.

When a train arrives at signal it is the only train to arrive at that given signal, so what you are most likely requesting is if a train cannot reserve a block it should queue as first for the reservation. This would work only in case of a rail signals, but in case of rail chain signals it would require train to be put in queue of multiple rail blocks, even when some of them are empty at that moment. There is no partial reservation (reserve only one block of a chain signal section) or forced reservation revokation (the rail block is reserved but the train was unable to reserve all rail blocks, lets cancel its reservation so i can pass as i have different path through the crosssection). By implementing that, it could happen that a train that can safely pass the crossection as its path is "guarded" by another train going in the same direction but on the adjacent rail - would have to stop at a rail signal that would be green and there would be no clear feedback as to why the train is waiting at the signal.

90247.png

If I understood your context right,
using the Rail signal at the right place seems to solve the problem. Let me try that.
Thanks for the explanation.

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