Two identical sets of trains, shared timetable, offset start times, increasing difference in distance between trains

Got a problem with OpenTTD? Find some help here.

Moderator: OpenTTD Developers

Post Reply
Seph
Engineer
Engineer
Posts: 13
Joined: 28 Mar 2012 14:17

Two identical sets of trains, shared timetable, offset start times, increasing difference in distance between trains

Post by Seph » 13 Feb 2019 22:16

Ok, so this might get a bit long-winded. Sorry in advance. I'm trying to set up a super tight, tokaido shinkansen-like train line. This means managing departures down to the tick in order to squeeze as many different services onto the tracks as possible. I set out to do this by first constructing a test train, and have it timetable the entire track. I then added some extra wait time at stations as a buffer, made forty-four copies of it, retired the original, and started launching the trains from a single depot. I did this in order to try and make sure that the time between each train was exactly the same. Once they had all entered service, I made another forty-four copies with the same shared timetable, and started sending them out from a neighboring depot, with their own platform. I offset their launch time slightly by waiting to activate the trains in the depot at just the right moment, so that they run as close to the previous departure as possible, without ever encountering any slowdown.

This works fine for the first 10-20 trains. However, once I got into the low thirties, it became very apparent that the gap between the two supposedly identical groups was growing. It is not due to their departure times being too close. Believe me, I've spent way too long taring at the trains leaving the station, trying to figure out what's wrong. This has completely killed my will to play. I've spent hours and hours trying to come up with some explanation, to no avail.

Have I stumbled upon a bug in the way OpenTTD keeps track of the trains? Or is there some natural explanation.

Here are the timetables(https://imgur.com/7m7awbr), a short video of the first pair of trains leaving the station(https://youtu.be/TWYxSxjuMs8), the last pair of trains(https://youtu.be/aEmlLA9kh5s), the launch of the first set of trains(https://youtu.be/PcAGjkTzEZo), and the second set of trains(https://youtu.be/ZIj5V7V2doc).

Help me TT-Forums, you are my only hope!!

EDIT:

I'm using version 1.8.0. You will find the savegame where I am about to launch the second set attached.
Attachments
Murphy & Co., Jun 20th, 2017.sav
(15.41 MiB) Downloaded 38 times
Last edited by Seph on 13 Feb 2019 23:59, edited 1 time in total.

User avatar
planetmaker
OpenTTD Developer
OpenTTD Developer
Posts: 9309
Joined: 07 Nov 2007 22:44
Location: Sol d

Re: Two identical sets of trains, shared timetable, offset start times, increasing difference in distance between trains

Post by planetmaker » 13 Feb 2019 22:30

You forgot to attach a savegame and to mention which OpenTTD version you play with :)

Seph
Engineer
Engineer
Posts: 13
Joined: 28 Mar 2012 14:17

Re: Two identical sets of trains, shared timetable, offset start times, increasing difference in distance between trains

Post by Seph » 13 Feb 2019 23:59

planetmaker wrote:You forgot to attach a savegame and to mention which OpenTTD version you play with :)
Sorry, fixed.

Seph
Engineer
Engineer
Posts: 13
Joined: 28 Mar 2012 14:17

Re: Two identical sets of trains, shared timetable, offset start times, increasing difference in distance between trains

Post by Seph » 19 Feb 2019 13:07

Has anyone had the time to take a look at this? Could I be looking at a bug?

gGeorg
Engineer
Engineer
Posts: 6
Joined: 02 Apr 2019 01:17

Re: Two identical sets of trains, shared timetable, offset start times, increasing difference in distance between trains

Post by gGeorg » 02 Apr 2019 01:33

Seph wrote:Has anyone had the time to take a look at this? Could I be looking at a bug?
Hello,
impressive city build. How big is it? Would you post some overview of your creation?

Regarding your issue, when you released all the trains, do you press in the TimeTable dialog Ctrl+"Start date"?
That command spread start date of all timetables in time, so trains space out evenly. No gaps, guaranteed. In fact, you don't need release trains manually to create spacing, rather release them at once then press Ctrl+"Start date" then let them fallow rules so they space out by themselves. :wink:

Seph
Engineer
Engineer
Posts: 13
Joined: 28 Mar 2012 14:17

Re: Two identical sets of trains, shared timetable, offset start times, increasing difference in distance between trains

Post by Seph » 16 Aug 2019 07:37

gGeorg wrote:
02 Apr 2019 01:33
Seph wrote:Has anyone had the time to take a look at this? Could I be looking at a bug?
Hello,
impressive city build. How big is it? Would you post some overview of your creation?

Regarding your issue, when you released all the trains, do you press in the TimeTable dialog Ctrl+"Start date"?
That command spread start date of all timetables in time, so trains space out evenly. No gaps, guaranteed. In fact, you don't need release trains manually to create spacing, rather release them at once then press Ctrl+"Start date" then let them fallow rules so they space out by themselves. :wink:
Sorry, I got so annoyed at this that I had to take some time away from the game. I'll be happy to post an overview if I ever get around this issue.

The problem is that I'm trying to have trains running with different stops, which means that, while the first set of trains can just be launched using ctrl+start, as you suggested, once I get to the ones with varying stop patterns, I kinda have to adjust wait times at the stations as they make their way along, to prevent them from blocking trains on different schedules.

What I've been doing is launching the trains with the fewest stops first, then, once the first train has returned to the terminus, I launch the next set of trains with a slight offset. These trains stop a slightly more stations, and whenever the first train in the set is about to reach a station the first set doesn't stop at, I save. I then adjust the wait time to ensure that the two schedules fit smoothly, and so on and so forth.

In my mind, as each train in a set waits for the same amount of time at each station, and launch with a common offset from the first set, I should only need to change the first train in a set. But for some reason, the gap between the sets slowly changes.

Is there a better way to do this?

Eddi
Tycoon
Tycoon
Posts: 7418
Joined: 17 Jan 2007 00:14

Re: Two identical sets of trains, shared timetable, offset start times, increasing difference in distance between trains

Post by Eddi » 20 Aug 2019 15:58

i'd advise you to show the timetable in ticks instead of days, so you can see whether there is any hidden rounding issues.

also, if you are into complex schedules, you might want to check out the "improved timetable management" patch (might be a little outdated now)

... and if you're using any conditional orders (this includes "service at depot" orders), then you've no chance...
You might not exactly be interested in Ferion, but if you are, have fun :)

gGeorg
Engineer
Engineer
Posts: 6
Joined: 02 Apr 2019 01:17

Re: Two identical sets of trains, shared timetable, offset start times, increasing difference in distance between trains

Post by gGeorg » 24 Oct 2019 20:46

Seph wrote:
16 Aug 2019 07:37
gGeorg wrote:
02 Apr 2019 01:33
Seph wrote:Has anyone had the time to take a look at this? Could I be looking at a bug?
Hello,
impressive city build. How big is it? Would you post some overview of your creation?

Regarding your issue, when you released all the trains, do you press in the TimeTable dialog Ctrl+"Start date"?
That command spread start date of all timetables in time, so trains space out evenly. No gaps, guaranteed. In fact, you don't need release trains manually to create spacing, rather release them at once then press Ctrl+"Start date" then let them fallow rules so they space out by themselves. :wink:
Sorry, I got so annoyed at this that I had to take some time away from the game. I'll be happy to post an overview if I ever get around this issue.

The problem is that I'm trying to have trains running with different stops, which means that, while the first set of trains can just be launched using ctrl+start, as you suggested, once I get to the ones with varying stop patterns, I kinda have to adjust wait times at the stations as they make their way along, to prevent them from blocking trains on different schedules.

What I've been doing is launching the trains with the fewest stops first, then, once the first train has returned to the terminus, I launch the next set of trains with a slight offset. These trains stop a slightly more stations, and whenever the first train in the set is about to reach a station the first set doesn't stop at, I save. I then adjust the wait time to ensure that the two schedules fit smoothly, and so on and so forth.

In my mind, as each train in a set waits for the same amount of time at each station, and launch with a common offset from the first set, I should only need to change the first train in a set. But for some reason, the gap between the sets slowly changes.

Is there a better way to do this?
Once you start fiddle time of each train manualy, you never achieve regular pattern.
I would suggest:
1. release first set
2. release second set
3. find the fisrt station of your timetable
4. wait for a train of the first set then press Ctrl+"Start date" when train comes in
5. wait for the very next train of the second set, stop him manualy in the station, then wait for offset, then release train and press Ctrl+"Start date"

That way you set two schedules with the offset.

It looks to me, by the screenshot that both timetables are totaly the same. same stations. But you say they are different, can it be possible that you miscallulate the delays for the missin stations ?

Post Reply

Return to “OpenTTD Problems”

Who is online

Users browsing this forum: No registered users and 2 guests