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Development => Bug Reports => Topic started by: Václav on January 11, 2013, 07:00:52 PM

Title: Bug in long block signals
Post by: Václav on January 11, 2013, 07:00:52 PM
I don't know how far is work on signals that will be special for trams (if it is in process) but still, when trams have not own signals (they share them with trains ... or rather said trains share them with trams), I use them in tram lines very much - mostly long block signals and one-way sign.

I found that sometimes, I really don't know why (and I don't undertand it), they let train/tram to go while else one is in track. And then two ones meet somewhere between two such signals - and all ones (trains/trams) are blocked.

Until this time I have found that it appears when three or more such signals are close to each other. And it is quite irrelevant if distance between them is short or long - but in case of long distances it is more often.
Title: Re: Bug in long block signals
Post by: prissi on January 11, 2013, 11:55:27 PM
With long block signals, several pitfalls are possible. Please show your setup, in most cases the design is such that those simply cannot work.
Title: Re: Bug in long block signals
Post by: Václav on January 12, 2013, 09:17:59 AM
What setup? Do you think screenshot?



Screenshot of the first critical hub is in attachment.

Red dashed line and violet full line are owned by one tram line.
Black full line is owned by else one tram line.
Yellow circles are signals.
Arrows mark direction.

Black tram is slow line - it stops in every station.
Red/violet tram is fast line - it stops only in stations where it can meet other line(s) - because track in left top corner is used by some other line that is not marked (highlited).

Red/violet line goes along to one side of rail track (as red) at first - and meets black line on other side of rail track. Then it goes together with black line. And then, it (as violet) departs area of black line - and meets itself that goes as red.

Critical track is where red and black line meet.
Title: Re: Bug in long block signals
Post by: kierongreen on January 12, 2013, 10:21:15 AM
Yes. The simplest example of having to think before using long block signals is:
1>-L-\       /--->4
2<-----A-B-C---L-<3


Line W: 1, A, B, A, 2
Line X: 3, C, B, C, 4
Line Y: 1, A, B, C, 4
Line Z: 3, C, B, A, 2


Line W and X will not work correctly as trains use two overlapping sections of single track. Hence one train can pass a long block signal when another is already in the section, just not on its route. Each line would work separately though, just not together.

Line Y and Z will work correctly as trains from both lines use the entire single track section.
Title: Re: Bug in long block signals
Post by: Václav on January 12, 2013, 10:55:35 AM
Quote from: kierongreen on January 12, 2013, 10:21:15 AM
Yes. The simplest example of having to think before using long block signals is:
1>-L-\       /--->4
2<-----A-B-C---L-<3


Line W: 1, A, B, A, 2
Line X: 3, C, B, C, 4
Line Y: 1, A, B, C, 4
Line Z: 3, C, B, A, 2

Line W and X will not work correctly as trains use two overlapping sections of single track. Hence one train can pass a long block signal when another is already in the section, just not on its route. Each line would work separately though, just not together.
But my trams don't go in accordance with W and X. They go in accordance with Y and Z - but only with small difference that one line stop in every station and other not - because they stop only in station where they can meet other trams like if they would be written

Line W: 1, A, B, C, 4
Line X: 3, 2

And what is very strange is that they go for some time as they should - and after some time they meet in station between long block signals.
Title: Re: Bug in long block signals
Post by: Ters on January 12, 2013, 11:34:34 AM
Have you tried look at how the reservations play out? Trains only reserve up to next waypoint, long block signal or not. Long block signals just look further before showing clear.