LL_RR T Junctions

[jugstah]

I've been scouring the forums and noticed there are not too many variations of a 3 way T junction coming off a LL_RR track into a hub/station so this is a call out to you track designers...

Hopefully there will be some really cool examples of fast junctions, compact junctions and so forth... I saw some topics but we need more variations..

[CommanderZ]

Welcome to TT-forums jugstah

Here are some of juctions I build in my game (it was before PBS)

This one probably wouldn't do very do very good under extreme load, but if you manage to keep traffic in reasonable levels, it will serve good. I think it is very space-effective - the smallest I could come up with.

ex1.png (295.63 KiB) Viewed 3643 times

Thisone is borrowed (copy & pasted ) and adapted from a OpenTTDCoop game - I needed a solid junction and wasn't in mood to design mine. I would recommend to you to go and visit their archives. It is literally an one big junction library

ex2.png (134.49 KiB) Viewed 3650 times

[Torben DH]

why not join some coop games and learn to build big junctions

[jugstah]

I could do that but I enjoy playing on my local machine against the AI for the meantime. I don't think I'd be qualified enough to compete against the "big boys"

Besides, I have to learn how to do away with the 45deg bends slowing down my trains and creating this huge station handling over 100+ trains in any given minute.

[Torben DH]

youll learn networking there i guarante you

anyway u should check http://www.openttdcoop.org/wiki to learn something they have an excellent tutorial to get you started...

[m1ch4el]

Here's my take on a fast 4 lane 3 way junction:

[Sande]

Trains coming from right can't make a left turn. Trains coming from bottom left can't make a left turn...

[jugstah]

Sweet... keep 'em coming, I like that concept.. I tried to make a variation of that but failed because I got confused between the trains needing to make their turns back onto the mainline...

And BTW, Torben, I did go there.. I've been googling and visited owenrudge sites, this site and so forth.. I guess I'm trying to get people to post some new ideas on the dual track stuff..

Seeing as I'm off tomorrow, maybe I'll try an opencoop game online if nothing pops up between now and tomorrow!

[ostlandr]

When I have an LL-RR junction, I make through traffic use the center two tracks, and make diverging traffic shift to the outer tracks.

In practice, I find that very rarely is there an equal volume of traffic coming from all four directions of a junction at once. If I find I have enough traffic going from A - Junction - B to clog the junction, that's when I build a direct line from A-B, or a bypass that avoids the junction altogether.

When a T junction becomes an X, I also add a third track just before the junction if needed, so that (for example) through trains continuing North stay to the far left, trains going North to West take the center of 3 Northbound tracks, and trains going North to East (not crossing over any tracks) go to the far right track.

[jugstah]

When I have an LL-RR junction, I make through traffic use the center two tracks, and make diverging traffic shift to the outer tracks.

In practice, I find that very rarely is there an equal volume of traffic coming from all four directions of a junction at once. If I find I have enough traffic going from A - Junction - B to clog the junction, that's when I build a direct line from A-B, or a bypass that avoids the junction altogether.

When a T junction becomes an X, I also add a third track just before the junction if needed, so that (for example) through trains continuing North stay to the far left, trains going North to West take the center of 3 Northbound tracks, and trains going North to East (not crossing over any tracks) go to the far right track.

Care to post a screenshot example?

[ostlandr]

Sure. Attached is an LL-RR "T" junction. Notice at the two circled areas, the trains can only diverge from the outside track to use the junction. So the pathfinder should send the trains to the outside track at the previous crossover. (BTW I did this one with path signals.)
Also note that the EB-NB track crosses under the flyover bridge for the SB-EB track.

When I have an LL-RR junction, I make through traffic use the center two tracks, and make diverging traffic shift to the outer tracks.

In practice, I find that very rarely is there an equal volume of traffic coming from all four directions of a junction at once. If I find I have enough traffic going from A - Junction - B to clog the junction, that's when I build a direct line from A-B, or a bypass that avoids the junction altogether.

When a T junction becomes an X, I also add a third track just before the junction if needed, so that (for example) through trains continuing North stay to the far left, trains going North to West take the center of 3 Northbound tracks, and trains going North to East (not crossing over any tracks) go to the far right track.

Care to post a screenshot example?

[ostlandr]

Here is a compact (too compact, actually) LL-RR full 4 way junction. I made this one a little too tight, so there are a couple of S bends and slow double-45 corners, but you can see the principle. Just make it a little bigger, and you should be able to fix those with angled tracks under bridges.