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Friday Facts #81 - Chain signals

Posted: Fri Apr 10, 2015 2:59 pm
by kovarex
3 years of Factorio in numbers and chain signal detailed info: https://www.factorio.com/blog/post/fff-81

Re: Friday Facts #81 Chain signals

Posted: Fri Apr 10, 2015 3:11 pm
by dee-
Yay, three years already! Congratulations :)


Re chain signals.
From the examples I see them used in situations where a rail is used where more trains can be than exits are. Your examples have usually two trains and one exit so they get guarded by chain signals.

Now, can't chain signals be automatically selected when more than one rail enters a block? See the # example: all signals on places where mroe than one rail enters is a guard signal, all others (the ones at the end of a signal chain) are normal signals, with only one rail entering the free, last block which is leaving out of the screenshot.

The same for the last example: then the parking slots join there's a chain signal bercause two rails enter that block. When the rail split a normal signal is used because there are less entering then exiting rails.

Question: is there a situation where chain signals are useful not covered by above rule?

Re: Friday Facts #81 Chain signals

Posted: Fri Apr 10, 2015 3:39 pm
by McGuten
Awesome game and awesome community, congrats!

Re: Friday Facts #81 Chain signals

Posted: Fri Apr 10, 2015 3:48 pm
by JackGruff
So the only difference is that these chain signals will chain only to the exit the train wants whereas openTTD's pre-signals let the train go through the first available green exit?

Re: Friday Facts #81 Chain signals

Posted: Fri Apr 10, 2015 3:57 pm
by kovarex
JackGruff wrote:So the only difference is that these chain signals will chain only to the exit the train wants whereas openTTD's pre-signals let the train go through the first available green exit?
Probably yes, and some other smaller differences.

Re: Friday Facts #81 Chain signals

Posted: Fri Apr 10, 2015 3:59 pm
by bonob
I was thinking, there's a lot of mentions to TTD whenever train pathing and signals are the topic, have you guys looked into how Simutrans manages the train pathing?
I wouldn't know if there are significant differences between Simutrans and TTD in the implementation of train logic, but since the simulation is overall quite different, it's very possible.

Re: Friday Facts #81 Chain signals

Posted: Fri Apr 10, 2015 4:16 pm
by Align
I'm trying to understand chain signals; do they have the same state as the next signal?

Re: Friday Facts #81 Chain signals

Posted: Fri Apr 10, 2015 4:27 pm
by Legoman165
Bentham will be very happy! This update will be epic, cant wait for more of an endgame then just rocket defence.

Re: Friday Facts #81 Chain signals

Posted: Fri Apr 10, 2015 5:34 pm
by ryannayr140
Align wrote:I'm trying to understand chain signals; do they have the same state as the next signal?
Yes! for most instances, this one being the most practical http://assets-factorio-com.s3.amazonaws ... ssroad.jpg A pre-signal copies the signal in front of it. This is very useful to keep trains from stopping in the middle of an intersection. Although the picture is an over simplification, crossings don't necessarily have to be two isolated lines. A practical example of where crossings may occur of you want to add a station off of two one-way tracks and do not want to put in roundabouts that only allow one train in at a time.

It gets a bit complicated if a pre-signal has multiple exits in front of it and is up to the programmers how they want the trains to behave. Just having a signal that copies the one in front of it will drastically increase the potential throughput of a train line. Think of it like driving, you're not allowed to enter an intersection if you know your path has no way to exit the intersection (due to traffic), even if you have a green light.

Re: Friday Facts #81 Chain signals

Posted: Fri Apr 10, 2015 5:41 pm
by masat
Wow, I didn't know Factorio will be the new TTD :D

I've been following the development for some time now. I didn't buy the game because I don't have the time to play it at the moment, anyway - but now that I've seen this you have sold one more copy ;) Hope it helps a little to make the process a bit faster

Re: Friday Facts #81 Chain signals

Posted: Fri Apr 10, 2015 6:48 pm
by Cordylus
I'm looking for the different name for the "chain signals". This one would be very bad to translate into Polish and very confusing.

Re: Friday Facts #81 Chain signals

Posted: Fri Apr 10, 2015 7:32 pm
by ssilk
- Forward-looking-signals?
- exit-signals?
- Free-path-signals?

Not much better.

Re: Friday Facts #81 Chain signals

Posted: Fri Apr 10, 2015 7:46 pm
by Nova
Well, just invent a new one. The translations don't have to be word for word if they don't fit.

Re: Friday Facts #81 Chain signals

Posted: Fri Apr 10, 2015 7:53 pm
by Cordylus
Nova wrote:Well, just invent a new one. The translations don't have to be word for word if they don't fit.
I know. That's why I'm looking for the different one.

Maybe "antecedent-signal"?

Re: Friday Facts #81 Chain signals

Posted: Fri Apr 10, 2015 9:16 pm
by Drury
Chain signal works in English, use whatever works in Polish I suppose "cascade signal" would also be a nice alternative.
bonob wrote:I was thinking, there's a lot of mentions to TTD whenever train pathing and signals are the topic, have you guys looked into how Simutrans manages the train pathing?
I wouldn't know if there are significant differences between Simutrans and TTD in the implementation of train logic, but since the simulation is overall quite different, it's very possible.
Routing is different (even more retarded), but there are still only good old block and pre-signals.

Re: Friday Facts #81 Chain signals

Posted: Fri Apr 10, 2015 9:46 pm
by Marconos
Really really looking forward to having these chain signals .... having said that, really looking forward to get my current clients project done so I can get back to playing!!

Keep up the great work.

Re: Friday Facts #81 Chain signals

Posted: Fri Apr 10, 2015 10:24 pm
by Cordylus
What do you think? How would be look like the new graphic of the chain-signals? Different color? Or maybe some sign... :|

I know the similar constructions in the real life:
Image

Re: Friday Facts #81 Chain signals

Posted: Fri Apr 10, 2015 10:29 pm
by DanGio
Way to go ! Thanks for these FF posts ! I really look forward to them while finishing work.

Re: Friday Facts #81 Chain signals

Posted: Sat Apr 11, 2015 1:05 am
by Ohz
Since you cannot make bridges and avoid crossings rails in Factorio, this totally essential. Thank you very much.

Oh and happy birthday :)

Re: Friday Facts #81 Chain signals

Posted: Sat Apr 11, 2015 3:32 am
by Ailure
As a Transport Tycoon and OpenTTD veteran, I'll assume that regular signals works a lot like the exit signals of said game, and chain signals works a lot like the combo signals of said game, but with the caveat that the train will wait patiently at the chain signal if it's chosen path is not available? (Unlike openTTD trains who just keeps going down whatever path happens to be open, even if it's wrong :P).

Train orders that would make the train wait on a certain load (to emulate the full load/unload behavior of openTTD ;) ) instead of having them to wait a certain amount of seconds would be nice too. Would make it bit more easier to manage having multiple trains at the same station, as the trains can leave as soon they're done (but I'm not surprised if this turns out to be planned to be put in at some point).