The road junctionary

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acs121
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The road junctionary

Post by acs121 » 10 Jun 2018 14:20

I'm seeing too much rail junction topics, so why not road junctions ? :D

I'm first going to input some definitions for the topic :
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acs121
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Re: The road junctionary

Post by acs121 » 10 Jun 2018 14:26

A road junction between a highway and an expressway separating with another expressway !
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ANIKHTOS
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Re: The road junctionary

Post by ANIKHTOS » 10 Jun 2018 17:21

acs121 wrote:A road junction between a highway and an expressway separating with another expressway !
nice now if only road vehicles could actual use the extra lines
even a 1 way street is a wast in the game and not fully used by road vehicles


how you create the highway??
3 lanes per side???

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Re: The road junctionary

Post by Transportman » 10 Jun 2018 17:44

ANIKHTOS wrote:
acs121 wrote:A road junction between a highway and an expressway separating with another expressway !
nice now if only road vehicles could actual use the extra lines
even a 1 way street is a wast in the game and not fully used by road vehicles


how you create the highway??
3 lanes per side???
There are NewGRFs that provide the third lane sprite and barrier. The Dutch Road Furniture has it for example.
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Re: The road junctionary

Post by acs121 » 10 Jun 2018 17:50

ANIKHTOS wrote:
acs121 wrote:A road junction between a highway and an expressway separating with another expressway !
nice now if only road vehicles could actual use the extra lines
even a 1 way street is a wast in the game and not fully used by road vehicles


how you create the highway??
3 lanes per side???
Actually lanes are fully used by road vehicles.
A vehicle going at 72 kph will pass a vehicle going at 64 kph if there's no road vehicle infront, and if not in a curve, not on a slope etc.
This applicates to normal roads as well as one-way ones.

The third lane on the highway is fake, it's from the NewGRF called "Dutch Road Furniture". Those are Newobjects that are meant to be placed between two roads which have a 1 tile space between them.

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Re: The road junctionary

Post by odisseus » 14 Jun 2018 01:02

No offense, but I believe massive road junctions are useless. The main reason is that, unlike trains, road vehicles don't reserve sections of the road. This means that:
  • Road vehicles going in different directions just pass through each other without blocking, which means no need for overpasses.
  • Road vehicles going in the same direction aren't blocked by moving traffic. They can queue up only if their path is blocked by something else* (such as full station or train crossing), and junctions don't address those situations.
  • Road vehicles already use the second lane for overtaking on normal roads, and the third lane is for decoration only.
  • If you have road jams not near a full load stop, this means that you have too many road vehicles and you should convert the route to rail or boat.**
  • If conversion is not feasible (say, for a bus route in the middle of a city), then building a road junction is not feasible either.
If your goal is recreating real life junctions, then, of course, my arguments don't apply. But in that case a junctionary would be of no use.

Now, there's a related thing that is not useless, and that is design of road stations. The only situation when road jams are hard to avoid is trucks queueing up in front of a full load station, because the very first loading slot is occupied. Actually, so far I haven't found an ideal solution for that.

* In fact, even in a queue they sometimes magically pass through each other. it is possible to cramp an arbitrary number of trucks onto the exact same spot, then smash them all at once with a locomotive, mwahaha
** The capacity of boat routes is limited only by the number of boats you can build.
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Re: The road junctionary

Post by YNM » 14 Jun 2018 03:36

odisseus wrote:The only situation when road jams are hard to avoid is trucks queueing up in front of a full load station, because the very first loading slot is occupied.
Make "parallel" stations.
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Re: The road junctionary

Post by kamnet » 14 Jun 2018 04:48

acs121 wrote:Actually lanes are fully used by road vehicles.
A vehicle going at 72 kph will pass a vehicle going at 64 kph if there's no road vehicle in front, and if not in a curve, not on a slope etc.
This applicates to normal roads as well as one-way ones.
Articulated vehicles cannot pass other vehicles at all. In addition, vehicles cannot pass on bridges unless the passing started on the tile immediately before the bridge head tile.
odisseus wrote:If your goal is recreating real life junctions, then, of course, my arguments don't apply. But in that case a junctionary would be of no use.
Because of the limitations and lack of features in road vehicles, yes this topic is mostly going to be about superficial eye candy. Still it looks fun. :)

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Re: The road junctionary

Post by mak » 14 Jun 2018 07:44

odisseus.

As per YNM use parallel stations but you could try removing the one way system then the vehicles could use both lanes to load and not just the one.

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Re: The road junctionary

Post by Quast65 » 14 Jun 2018 12:10

Here is an example of how I make my cloverleaf-highwayjunctions:
Example432.png
Example432.png (169.28 KiB) Viewed 1114 times
By deleting the unneeded entrances/exits you can then also make T-junctions:
Example433.png
Example433.png (111.48 KiB) Viewed 1114 times
Depending on the direction of the T-junction, you may need to flip the direction of the bridges ofcourse..
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