Possible land ownership/station bug

[merry]

Hi,

Playing in the current 'released' Exp & Pak Britain (Simutrans 110.6 Experimental 10.3 & PakBritainExp 0.8.3).

I have one or two tiles where trains behave very oddly, and it appears to be due to land ownership issues.
The tiles in questoins have track and a station on them (and are overhead DC electrified). The station has two platforms (one per track), signalled one per direction, each of 3 tile length - plenty for the 3-car units using it. When a train is routed to a scheduled stop on one platform, it passes through that platform, perfoms a u-turn on a crossover just after, and actually calls at the other platform. It then either reverses to continus it's journey, or (more oddly) determines that it is calling on the return journey, and steps to the next station in the other direction, thus skipping to a new point in the schedule and missing some calls.

Investigating, after building a new schedule in case the original was corrupt, i removed electrification, platform & track, then rebuilt. One platform tile would not allow a statoin to be built (but would allow track & probably electification) - it said "Land owned by another player".
Well, the game is single player with no AI players (monopoly - yay!). So I changed to public player, and surprise! i got the same error.
The tileis in a town, at the edge - but so are all the adjacent platform tiles and the track.

I have not yet tried a workaround, but the only thing i can think of is to build the station one tile across avoiding this tile.
I did have other routing issues building this new suburban line - for no apparent reason, trains often had 'no route', when there was a clearly visible route and there were no gaps. Repeated rebuilds did eventually fix it but it was definitely 'hard work'.
i could upload the save game, if there is a place to put it...if you'd like the save, please ask. I can check the build versions if you like.

[jamespetts]

Can you upload your saved game to http://files.simutrans-germany.com? Thank you for the report!

[jamespetts]

Can you re-test with 10.5 and upload your saved game if the problem persists?

[merry]

Hi
Not had much time to play recently, but tried it this morning.
With the latest ST-Exp-10.8 released package, the bug persists. Affects the Honeybury Suburban line at the second/last station (there are two versions of teh line, an experiment to see what is happening - and althoguh the Honeybury Sub-A line was build today, in 10.8, it still has the same bug!).
File is at http://simutrans-germany.com/files/upload/simu-exp-brit128_X-14f.sve
Might be related to platform choice: the trqains always choose the wrong one of the two platforms. Very Weird!! And of course causes pretty strange routing.

I'll be interested to see what you make of it. Hope the descriptoin makes sense.

Cheers,
Merry

[jamespetts]

May I ask - which second last station do you mean - Parade Ground or Honeybury main? They seem to work fine at Parade Ground, always taking the left platform according to the signalling. At Honeybury main, the platforms are signalled to be bidirectional, so the trains choose the Westward platform by preference when going in both directions, as the rule is that the trains will use their first choice platform (that marked in their schedule) as a first choice and will only use another platform if necessary (and where permitted by signalling or the "mirror schedule" feature). The line from the North is governed by a choose signal, which means that trains from the North will sometimes use the Eastern platform when the Western platform is occupied (as it sometimes is with the Warwell Dock - Honeybourne semi-fast service), but not otherwise. If you want the trains from the North always to use the Eastern platform, you would have to make the suburban platforms at Honeybury main unidirectional using unidirectional signals, but that would probably not suit the semi-fasts, which need to turn there. One option would be to make the Eastern platform the platform of choice for the Warwell semi-fasts, and have them use the Eastern lines into Honeybury main, restricting the suburban trains to the Western lines, which would reduce movement conflicts in the Southern part of Honeybury main.

From what I can make out, the program is working as intended, and your layout is only marginally inefficient. (I have to say, if it were me, judging by the passenger numbers, I'd replace the whole route with about three single decker 'buses, which would eliminate all these problems entirely, but perhaps you think that the residents of Honeybury deserve the comfort of the train, and, really, who am I to judge your public service ethos? ).

[merry]

OK, I wasn't very clear was i?
1. the station in questoin is Parade Ground
2. your comments on Honeybury (main) station are valid, the platforms are deliberately bidirectional and use lighter track & electrification only off the main route, to keep the main lines free for fast traffic. There have been some queues of traffic here in the past, currently the issue is resolved. You'll note the electrification is deliberately designed to route slow trains off the fast lines - and it works too!
3. Passenger numbers are lower than when the line was installed, but it has been put in to reduce the number of buses needing to go to the main station, and to cope with future expansion (Honeybury's been growing rapidly recently) without lots of expensive demolition.
I also fancied experimenting with Experimental's OHLE electric trains to be honest!
4. the issue is a weird one, and you ahve to watch very carefully to work it out. Trains DO call at the left platform in directoin of travel,...at the moment they call...but they always choose the 'wrong platform, and perform a U-turn at the end of the double track section to get to the platform...twice!
Let's do the ascii diagram trick
to/from             /-==1=>------>-/--------===
HBM-------===-----/-<==2=-<------/
            A      X    B  N      Y          C
> : signal (1-way), === ; platform, statoin B is parade ground
A train approaching from HBM will call at the intermediate station A, and is booked to call at B platform 1, which is signalled left-right only.
It will pass through B1, go to Y, perrform a U-turn, then call at B2, do another U-turn at X, pass through B1 again, and call at C
In the reverse directoin, leaving C, the routh is C - Y - B2(booked stop but does not call) - X(u-turn) - B1(calls) - Y(u-turn) - B2(Nonstop) - X - A(calls) - HBM.
Interestingly, watching the schedule as the train misses the booked call, the schedule skips to the entry for the other platform in the reverse leg of the journey, then skips back to the next correct stop.
So if the schedule were
HBM
  A
B1
  C
B2
  A
then the train schedule will go to A, and then skip to B2, then skip to C, then skip to B1, then A (then HBM). Like i said, weird, and I only found it because the u-turns are slow and block the line for the other train. I put in the signals at N as part of diagnosing the problem, I had deadlock without them! ordinarily they are not needed for a line to run properly.

Ok, I hope this makes sense. I can't fire up the sim as I'm at work (lunch time forum browse) so i hope it is all correct - I believe so.

Cheers,
merry

[jamespetts]

I did not see this in my observations - I checked for any weirdness like that. I followed both trains over a number of complete journies and found nothing of the sort.

Does it only appear when one of the two lines are used?

[merry]

OK, This is wierd.

Upon reloading and running with ST-E 10.8, I find the reported but on that line has gone. Yay! So I think maybe I was going a bit mad. Happens...
But now I can play the game. More Yay!

SO I look around the map, find things to improve/fix/whatever.
And a line needs a bit more capacity, another loop & station, so I add it, and a couple of trains to take the line to capacity.
Again, the line is single track with passing loops at stations (& elsewhere) - semi-rural branch. Trains are push-pull sets for efficeint operation. Then I note that funny u-turns are persisting past the timetable change.
Looking at the schedule, I see multiple [R] tags at intermediate stations, not just the termini. These are non-reversing statoin platforms. Oh dear, things are reversing here, there, and everywhere, as described for the previous line, but worse!

I am uploading save and screenshots to files.simutrans-germany.com  - will post links in next message.
Could you look into this because it is definitely not right.
I have upgraded to ST-E 10.9 for this test, FYI.

Cheers,
Merry.

[merry]

Links are
http://simutrans-germany.com/files/upload/simscrTEL.png
and
http://simutrans-germany.com/files/upload/simu-exp-brit128_X-14f2.sve

NOt sure what is happening here!
best of british finding bugs...
merry

[jamespetts]

Hmm - you had the schedules set up to reverse manually, yet many of the schedules were set to "reverse route". If you intend to insert both the forward and reverse routes on the schedules manually, do not set some of the convoys to "reverse route". When I cleared "reverse route", after a while, the stations started to work correctly.

I suspect that the "mirror schedule" feature might have some difficulties with single track lines and stations where it can easily find its intended platform if only it performs a u-turn. However, removing all of the "reverse route" designations here caused it to work properly.

[merry]

Hi,

Hmm. I note that the route in question is not set to mirror or alternate directions. The reverses in stations indicated on the schedule (in the screenshot) were not inserted by me - at least, not knowingly. [on that point, how would one make a shcedule always reverse direction at a platform?]
To me the question is: did the game insert these automatically, or is there a key combination to do so that i inadvertently used? if so, what is it? My understanding was that the game will insert [R] marks into a schedule automatically when it deems them necessary. In this route (and elsewhere when it's occurred) they are definitely un-needed

AFAIK, mirror and  alternate direction is only used on bus/ferry routes in this game (Ok, there might be the odd train, but very few, and probably an experiment I forgot).

Like I said, it looks weird, but I accept that there may be a perfectly rational explanation. i just need to have it explained to me...I think I might be being a little thick so please feel free to put it in simple terms :-)

Oh, and please don't take these comments as criticism, it's intended to try to identify bugs and/or user idiocy! ST-Exp is such a cool development of Simutrans, which has come so far since I first played (maybe about version 0.6 or so, when it was Hajo and a semi-closed dev group!?) and so many of the annoyances and rough edges - not to mention apparent impossibilities -  have been ironed out by a whole crowd of dedicated devs over those years. 

Cheers,
Merry

[jamespetts]

Ahh, I think that there is some confusion here between reversing points (marked with "[R]" in schedules) and the "reverse route" setting.

The "reverse route" setting is set either manually, or automatically by the mirror schedule/alternate directions features.

The reversing points are set automatically based on checking when a convoy actually does reverse when it gets to a stop: it is, in other words, reactive to, and not causative of, reversing.

Does this make things clearer or modify the nature of your report?

[merry]

Well, this sort-of-modifies the terms of description. Something I expect you to be careful about in your line of 'day job' (and I definitely should be) - so it is well to clarify before we go further.
What we have in the latest example is an excess of reversing points, which make no sense in terms of the schedule under consideration (let's stick to just this schedule for now).
The line is linear, and reverses only at the two ends (Queenminster and Murdingchester Gaol Street), according to the intended route programmed.
But the schedule clearly shows [R] at Hollywich & Parwell (outbound) and Murdingchester Forest Street (both ways).
Now, I've checked, and with the left-handed running as signalled at all loops, the platform allocations are clearly correct(grid ref checked carefully).
So where are all these reversing points coming from?
NB the line is programmed traditionally - no Mirror Schedule set, as you can see in the screenshot.

Hope this helps you in analysis.

<edit 0930 7-2-2012>
I have now checked thoroughly, and it is definitely WEIRD.
Following the 5 trains of line TRP-06A, they are - apparently randomly - swtiching the 'mirror schedule' parameter on, and sometimes even displaying the parameter as checked.
The line is changin the stations where [R] is displayed - again seemingly at random. At one point, the line had reverses at each end - hurrah, it's working!
But then [R] tags crept in at one then another station. I tried moving some trains to the (nominally identical) TRP-06 line, which correctly showed [R] tags. As the trains moved through their route, the line mutated and started to add [R] tags at intermediate stations. I checked often to verify this.
I am wondering whether this is realted to the direction the formations are travelling in - these are push-pull sets and perhaps the line is mirroring the schedule at reverses. it is interesting that if the [R] tag causes a train to do a u-turn, and I catch it partway through, and force the correct next station to be chosen, the train will often then continue in reverse formation and behave sensibly (ie follow the schedule) to end of line, where the set reverses and sometimes the palaver starts all over again, with random [R] tags appearing. Even worse, I think that if I edit a faulty schedule, the line seems to get updated wrongly, and then propogate to other trains at the next stop. Aaargh!

if i abstract the problem slightly, consider the line
A - B1 - C1 - D - C2 - B2  where ABCD are stations and 1, 2 are opposite platforms signalled for the normal direction of travel.
the train might travel A-D normally, but then travel D -C1 (via C2 & u-turn) - (u-turn again, through C2 & B2, u-turn) - B1 - (u-turn & through B2) - A (at the start of line again)
it looks like the train is travelling a mirror schedule, but the line was not set up with mirroring, and this unbidden change really makes very bad operational sense!!
To add to the fun, the train might or might not behave correctly after returning to A. It does all appear rather inconsistent.

This does look really nasty to debug, i can't fathom out what is happening at all, i do hope someone can! FYI, this is the latest released 10.9 version now.

merry.

[merry]

Hi,
I investigated more, and I have observed some trains to follow the line 06A schedule OK, whilst others on the same line and with the same displayed schedule actually traverse it in reverse, at least some of the time. When doing so the 'Mirror schedule' and 'alternate direction' buttons are not displayed depressed...that is just me :-( This makes no sense. It's also a bit consistent because the issue has been observed across 2 versions (10.8 & 10.9) and on 2 machines.
The result is that from time to time the line becomes gridlocked, and when the trains have the correct next station assigned manually (by setting next stop in the schedule dialog), they go to it then resume their errant schedule. Wacky stuff, and deeply frustrating. I dare not amend any other rail schedules at present...
Hoping for some ideas, Merry
BTW I could upload a new saved game if it helps. Just ask.

[jamespetts]

Apologies that I have not yet had a time to get around to this - working on server desyncs. Yes, please do upload a new saved game - it will help when I get an opportunity to look at this. Thank you!

[HDomos]

Hi,

Investigating, after building a new schedule in case the original was corrupt, i removed electrification, platform & track, then rebuilt. One platform tile would not allow a statoin to be built (but would allow track & probably electification) - it said "Land owned by another player".
Well, the game is single player with no AI players (monopoly - yay!). So I changed to public player, and surprise! i got the same error.
The tileis in a town, at the edge - but so are all the adjacent platform tiles and the track.

I have something like this bug in a totally different situation... In this game http://forum.simutrans.com/index.php?topic=9256.0 i wanted to build the monorail station on a tile previously used only by the town, and it says: "Land owned by another player" even when i try it with public player.
Edit: the tile is:(150;145;-1)

[ӔO]

currently, it is possible to overwrite another player's tracks or roads by using a faster ones than laid down, but I think this is from standard.

[jamespetts]

currently, it is possible to overwrite another player's tracks or roads by using a faster ones than laid down, but I think this is from standard.

This is not, and is not intended to be, possible in the current version of Experimental.

[ӔO]

This is not, and is not intended to be, possible in the current version of Experimental.

oh, yes, I mean it's a bug carried over from standard.

[jamespetts]

I tested this earlier when you mentioned it, and I cannot reproduce this bug. Can you give specific steps to reproduce?

[ӔO]

you have to do it with allow access on.

player 1 draws a low quality track
player 1 allows access to player 2
player 2 can now overwrite player 1 tracks of low quality with higher quality track

[sdog]

i can confirm that on 10.x

[killwater]

I do believe I have problem to that from the first post. I've  just demolished a bus stop then wanted to build a new one but I got a message "this piece of land is owned by another player". I do not have any other players and rebuilding the whole road doesn't make any difference.

[jamespetts]

Killwater,

can you upload the saved game in which you are experiencing this issue?

[ӔO]

it won't work with a saved game, because the problem goes away after a reload.

it's pretty rare, but sometimes you can't build a station tile on land you own after deleting the previous one that was there.

[omikron]

I confirm ÆO's observations. It occurs very very rarely and I cannot find a savegame where it appears, although it happened again just yesterday. Nothing helps, not even changing to public player, removing the road in question, changing back to default player, rebuilding the road and then trying to build a station on it.
omikron

[jamespetts]

Hmm - it'll be enormously difficult to find the problem without a reliable means of reproducing it, I'm afraid :-(

[killwater]

That's true it works after reload. Maybe someone will be able to get a save shortly before it occures and then it can be reproduced in the same location.

[jamespetts]

That would be very helpful.

[merry]

Finally got around to posting the last save file. Not had much time fo ST (or a lot else) recently; where did February go?

File at http://simutrans-germany.com/files/upload/simu-exp-brit128_X-14f4.sve, see previous description round a month ago.

merry.