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Sideline into mainlinne

Posted: 31 Oct 2009 12:02
by resurrection
I have a querry. I was thinking about two designs of how to join sideline into two-tracks mainline and came across two options.

1) First one is joining from one nod into either lane.
Join in the middle.png
Join in the middle.png (128.87 KiB) Viewed 578 times
2) Second one is joining at one spot and if that is not possible continuing to the other lane through buffer zone (1 train at a time).
Split before join.png
Split before join.png (168.73 KiB) Viewed 578 times

I see advantages in both designs, but which one do you think is better or more importantly, potentially faster? My rough guess is they are equal so it's rather matter of taste/style/visual then actual performance... Or not?

Re: Sideline into mainlinne

Posted: 31 Oct 2009 12:05
by lawton27
I'm not much of a networker but personally I'd prefer the second.

Re: Sideline into mainlinne

Posted: 31 Oct 2009 12:36
by petert
I wouldn't build either. Both of them block mainline traffic, and both of them have bad Curve Lengths. Look at Mark's Blog Post on #openttdcoop

Re: Sideline into mainlinne

Posted: 31 Oct 2009 13:22
by resurrection
Ah, you are right of course. Completely forgot about the tiny gap between the combo and entry pre-signals... Nevermind :-) I am considering using mainline shifting when joining the sideline rather than this classical styl. But thx!

Re: Sideline into mainlinne

Posted: 31 Oct 2009 13:28
by planetmaker
petert wrote:I wouldn't build either. Both of them block mainline traffic, and both of them have bad Curve Lengths. Look at Mark's Blog Post on #openttdcoop
Neither blocks ML traffic as they have prios in both cases. Given the choice of the two I prefert the middle join as there's no slow curve length (but that can be fixed for the 2nd one, too).

I meanwhile prefer to have between the split point of the SL to either choose ML1 or ML2 one trainlength waiting space in case that the priority makes the entry signal red. That way a 2nd train coming from the SL has still the chance to enter the other ML, if it is free.

EDIT: spelling

Re: Sideline into mainlinne

Posted: 31 Oct 2009 13:38
by petert
@planetmaker, sorry, incorrect wording. If an SL train is trying to merge, but an ML train has priority, then the SL train blocks the line for another SL train to merge the other ML.

Re: Sideline into mainlinne

Posted: 01 Nov 2009 12:46
by audigex
I don't think it matters as long as you're careful not to let the ML be stopped, and to make sure that a train waiting for one line doesn't block access to the other.

Re: Sideline into mainlinne

Posted: 04 Dec 2009 15:33
by bwong
question: Why are there so many needless turns in the first picture?

Re: Sideline into mainlinne

Posted: 04 Dec 2009 15:39
by planetmaker
bwong wrote:question: Why are there so many needless turns in the first picture?
I see exactly one which is not needed. Which do you see?

Re: Sideline into mainlinne

Posted: 04 Dec 2009 17:19
by bwong
like in the first picture, I see A LOT of turns that go like this: <<<< so needless 90 degree turns
ill try to show it in a picture...
EDIT: picture

Re: Sideline into mainlinne

Posted: 04 Dec 2009 17:51
by planetmaker
bwong wrote:like in the first picture, I see A LOT of turns that go like this: <<<< so needless 90 degree turns
Read up on priorities.

Re: Sideline into mainlinne

Posted: 04 Dec 2009 19:03
by petert
I can't view the picture on this computer right now, but if you're talking about 90 degree turns with backwards presignals on them, they are priorities, which give...well...priority to a line. Go to planetmaker's link.

Re: Sideline into mainlinne

Posted: 05 Dec 2009 00:23
by Badger
Of course it looks damn ugly though!

Re: Sideline into mainlinne

Posted: 05 Dec 2009 00:27
by Benny
That may be, but they're damn effective. :wink:

Re: Sideline into mainlinne

Posted: 05 Dec 2009 17:07
by audigex
It's possible to make priorities which don't look anywhere near as ugly, but they only really work for simpler systems - once you get into multi-line priorities they can cause problems.

Just put 2-way combo signals back along the mainline, and a start pre-signal on the sideline.

Re: Sideline into mainlinne

Posted: 05 Dec 2009 18:37
by petert
Could you post a screenshot of how you would do it? I think I know what you mean, but I'm not sure.

Re: Sideline into mainlinne

Posted: 05 Dec 2009 20:36
by audigex
Here you go.
prio.png
prio.png (36.26 KiB) Viewed 2768 times
As always, the realism comes at a cost. It looks a lot more like a realistic layout, but it drastically increases the follow-on distance between trains on the main line.

As such, it's best used for high speed lines with less traffic - it's no good for coop-style very busy networks. If you've got that many trains, however, you probably aren't going for realism anyway.

I use it if I've got a very high speed dedicated line with few trains, just to avoid ever stopping a train on the main line. It can also be used to allow grade-crossing of a small track. ie a small passenger line can cross a high speed main line without a bridge. I'll throw up a demo of this in a sec if I remember.

Re: Sideline into mainlinne

Posted: 05 Dec 2009 20:42
by Benny
Using that is highly inneficcient, as it stops traffic coming down the ML too.

There was a PBS patch that worked just like that, just without the part where it stops traffic on ML.

Re: Sideline into mainlinne

Posted: 05 Dec 2009 20:51
by petert
Audigex, have you actually tried that? It won't work...

Re: Sideline into mainlinne

Posted: 05 Dec 2009 21:00
by Benny
Um, yes it will.. Problem is that, as I've already said; it will stop trains on the line with priority.