Signals on 2track railway

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Rollerghost
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Signals on 2track railway

Post by Rollerghost »

2track2ways.png
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How do I best place signals on these tracks to make sure both tracks can be used both ways with traffic going as smooth as possible? THe WIKI is somewhat confusing when it comes to the use of signals.
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Pyoro
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Re: Signals on 2track railway

Post by Pyoro »

Path signals facing inwards everywhere would be my suggestion, although that's far from perfect. Altogether, I'd strongly recommend deciding a direction for each lane ...
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Eddi
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Re: Signals on 2track railway

Post by Eddi »

two-way traffic like this is prone to locking up, i would recommend a one-way setup.
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Pyoro
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Re: Signals on 2track railway

Post by Pyoro »

Yeah, it'll lock up if you have 2 trains going into the same direction trying to enter a station that already has 2 trains waiting. I guess you could build around that by forcing trains through depots, but seriously, at some point you have to ask where the advantage is ... and I can't see any. It actually needs more tracks (those crossings), the same number of signals, is less flexible, trains cross each others paths causing delays, and lockups are a topic to consider. So. Yeah. 1-way traffic is the way to go in basically all situations ^^;
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Re: Signals on 2track railway

Post by Rollerghost »

Thanks guys, I will use one-way system then. Is path signals in front of junctions and simple block signals on the main line OK?
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Pyoro
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Re: Signals on 2track railway

Post by Pyoro »

Sure, but make sure you don't mix them in the same block. But really, you need is 1 one-way signal at the of the line (so it's actually one way) and everything else can easily be two-way PBS signals. Best keep things as simple as possible.
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Nice and tidy.
(if you see trains doing weird things (like driving at the back of a oneway signal...) it's only 'cause they have no destinations. This can't ever lock up as long as the train length is not longer than the signal blocks, in this case 2 tiles. I guess there's the theoretical case of having more trains on a line than total signals blocks available but I've never had that happen ^^)
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Re: Signals on 2track railway

Post by Taschi »

You should use Block Signals instead of Path Signals everywhere where there are no points, because Path Signals use more CPU power. Does not matter on small maps, but might ruin your game if you play on bigger ones.
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romazoon
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Re: Signals on 2track railway

Post by romazoon »

Taschi wrote:because Path Signals use more CPU power
i believe it s a legend...
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Re: Signals on 2track railway

Post by Rollerghost »

I always use path signals only and have never had anything to indicate too much strain on the CPU.
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V453000 :)
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Re: Signals on 2track railway

Post by V453000 :) »

Some of our ancient tests did show massive difference in some extreme cases, but for normal playing the CPU difference is totally not noticeable.

If you use block signals, you will be able to see good solutions as a player and try to work things out properly, while Path signals just lead you to more and more hacks. If you want to learn to build good networks, block signals are better for you. If not, not.
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epictetus
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Re: Signals on 2track railway

Post by epictetus »

V453000 :) wrote:If you use block signals, you will be able to see good solutions as a player and try to work things out properly, while Path signals just lead you to more and more hacks. If you want to learn to build good networks, block signals are better for you. If not, not.
What is it about block signals that lead a player to build "good networks"? I always use path signals but I never considered that block signals could improve a network given their limitations. Could you give an example? Also, by 'proper' and 'good', are you appealing to aesthetics or functionality?
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Re: Signals on 2track railway

Post by FLHerne »

epictetus wrote:What is it about block signals that lead a player to build "good networks"? I always use path signals but I never considered that block signals could improve a network given their limitations. Could you give an example? Also, by 'proper' and 'good', are you appealing to aesthetics or functionality?
Block signals enable all sorts of interesting tricks, priority merges being the most common/useful example.

The kind of many-intersecting-tracks junctions that path signals are needed for aren't usually very efficient, although I tend to build small path-signal-based flat junctions and approaches unless there's an actual need for something fancier.
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V453000 :)
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Re: Signals on 2track railway

Post by V453000 :) »

Shortly said: you cannot create huge "connect everything to this huge X crossing and put Path signals there" with block signals - the huge X would just jam. With block signals the proper solution becomes obvious - you have to split things in order to use more blocks. Path signals tend to lead you to connect more things to that crossing; even though it is terrible.

The fact that block signals in the form of pre-signals allow for some fancy stuff is kind of irrelevant here, but helpful to learn at some point too.
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epictetus
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Re: Signals on 2track railway

Post by epictetus »

Interesting. I'll try tweaking one of my games and see what happens if I try and redesign intersections without path signals. It's been a long time since I've used block signals.
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