Author Topic: Freeway roundabout interchange  (Read 5200 times)

0 Members and 1 Guest are viewing this topic.

Offline Isaac.Eiland-Hall

  • Benevolent Dictator
  • Administrator
  • *
  • Posts: 3429
  • Total likes: 320
  • Helpful: 91
  • PanamaCityPC.com/support/
    • Facebook Profile
  • Languages: EN
Freeway roundabout interchange
« on: March 17, 2015, 12:00:18 AM »
Inspired by this Cities: Skylines screenshot:



http://i.imgur.com/ci5Nc0p.jpg

Source: http://www.reddit.com/r/CitiesSkylines/comments/2z8wfj/taking_my_highway_interchange_virginity/

I've created a couple of versions of it in Simutrans:



http://ieh.im/i/494.png

and one I like better:



http://ieh.im/i/495.png

Although technically the second one isn't a roundabout. :)
« Last Edit: February 10, 2016, 03:38:15 AM by IgorEliezer »

Offline isidoro

Re: Freeway roundabout interchange
« Reply #1 on: March 17, 2015, 01:43:23 AM »
I like them!

Offline DrSuperGood

Re: Freeway roundabout interchange
« Reply #2 on: March 17, 2015, 04:44:15 AM »
The top one is prone to crashing outside of nightly builds and even then could deadlock due to cyclic interchange dependencies.

The bottom one looks neat and is more compact. However I think you forgot to connect the North East (top right T pieces) so is not fully functional.

Would be interesting to know if these structures can actually help or if they end up being purely cosmetic.

Offline el_slapper

Re: Freeway roundabout interchange
« Reply #3 on: March 17, 2015, 03:31:35 PM »
you need zounds of fast buses for such monsters to be useful. I usually upgrade to trains much before reaching this level of use. Still, it is impressive. Good job.

Offline Dogstar

  • *
  • Posts: 4
  • Total likes: 0
  • Helpful: 1
  • Pixler for pak.german(Metro) and pak192.comic
  • Languages: DE (en)
Re: Freeway roundabout interchange
« Reply #4 on: March 17, 2015, 05:59:16 PM »
Looks cool. I like it :)

How useful is it for Simutrans? Maybe it would make my Interstate Problems bigger ;)

Offline Isaac.Eiland-Hall

  • Benevolent Dictator
  • Administrator
  • *
  • Posts: 3429
  • Total likes: 320
  • Helpful: 91
  • PanamaCityPC.com/support/
    • Facebook Profile
  • Languages: EN
Re: Freeway roundabout interchange
« Reply #5 on: March 17, 2015, 06:18:12 PM »
After some testing: Busses will go over the bridge, but on the second one, they'll take the slower 'ramp' instead of going down-and-back-up. :sigh:

edit: With no changed to the roads, they're now routing down-and-back-up. WEIRD.

edit2: It can handle a bit of traffic. Also, I tweaked and added right-turn ramps.



http://ieh.im/i/497.png
« Last Edit: March 17, 2015, 06:42:05 PM by Isaac.Eiland-Hall »

Offline Ters

  • Coder/patcher
  • Devotee
  • *
  • Posts: 4866
  • Total likes: 202
  • Helpful: 108
  • Languages: EN, NO
Re: Freeway roundabout interchange
« Reply #6 on: March 17, 2015, 07:09:13 PM »
After some testing: Busses will go over the bridge, but on the second one, they'll take the slower 'ramp' instead of going down-and-back-up. :sigh:

edit: With no changed to the roads, they're now routing down-and-back-up. WEIRD.

Going up and down is probably considered as costly as four 45-degree turns. Vehicles will then use path with least traffic, causing them to switch between the two periodically.

edit2: It can handle a bit of traffic. Also, I tweaked and added right-turn ramps.



http://ieh.im/i/497.png

The drawback is that all vehicles will turn left in the center. If there is a lot of traffic turning left from multiple directions, this will be a bottleneck.

Offline Isaac.Eiland-Hall

  • Benevolent Dictator
  • Administrator
  • *
  • Posts: 3429
  • Total likes: 320
  • Helpful: 91
  • PanamaCityPC.com/support/
    • Facebook Profile
  • Languages: EN
Re: Freeway roundabout interchange
« Reply #7 on: March 17, 2015, 07:14:04 PM »
Watching it run for a while with fast busses, then replacing with slower trucks:

Quote
If there is a lot of traffic turning left from multiple directions, this will be a bottleneck.

It looks to me like this is not really much of a problem. There were some times when things backed up, but it never appeared that that intersection was the cause - it was always from the stations (out of this screenshot) backing up. And the interchange was able to clear itself as traffic got going again, which is critical.

But I also found that using slower trucks would cause them to use the 'ramp' to go straight since they saw no benefit from the higher speed of the freeways...

So ultimately, this is probably not useful in Simutrans for that reason alone. :)

Offline alexko

Re: Freeway roundabout interchange
« Reply #8 on: April 06, 2015, 05:24:13 PM »
Nice
it can help to deal with traffic jam