Creating smooth highway exits - a guide

In this guide I explain how to build a smooth highway exit. It will show you some basics based on a complete straight and flat highway. You can use the basics to adjust towards more difficult situations in your own maps. Have fun.

Introduction

Introduction

In this guide we will show you how to build a smooth nice looking highway exit. This guide is based on a situation where there is a complete straight and flat highway.



If you understand some of the principles, you can use those principles and create more complex intersections in game, and adjust according to the situation in the map.

Note: I am not a native English speaker. All suggestions for improvement are welcome.

Note: This guide uses the mod Precision Engineering. Although I do think it can also be done without mods.

Step 1 - Creating Guidelines

Buildiing more complex structures is much easier when using guidelines. To help us with this we will use the basic roads to create our guides and remove them when we no longer need them.



At first we create a section of road of 5 units long at 90 degrees to the highway.



And we will do the same to the other side.



With these guideline roads we will create parallel roads next to the highway with the highway ramp type road. Those roads needs to be 50 units long minimum.



And also a parallel road on the other side



Then we create another guideline road. First we extend one guideline road by another 15 units.



And then we create a road along the highway with a marker road half way. We are going to use this road as the starting point

.

Step 2 - The first overpass

We will still use the basic road type because this type is easier when you need to measure.

Now can we start with the first overpass. First we build a road from ground level, 12 unit long to a height of 9 meters.



The next step is extend the road by 7 untis until it reaches the middle of the highway.



And then we will extend the road to the other end. An important distance is the 5 unit length beween the highway and the parallel road. This 5 units we need for calculation of how long we need to extend the overpass. The length of the extention is based on the radius of the circle we are going to build. The length of the extention and the radius need to be the same.



Since we extend the road by 7 units, see picture below, we have already done 2 units of the extention. That is marked with the red line.



We are going to create circles with a radius of 6 units. Therefore we need to extend our road by 6 units from the parallel road. Since we have already done 2 units (7 units minus 5 units), we extend our road by another 4 units to make it 6 units. This 6 unit length is marked with a red line below.



Now we going to draw the first part of the circle. We create a semi circular road of 6 units by 6 units, and with an angle of 90 degrees. At the same time we lower the height to 6 meters. The height is marked in green.


We do this a second time, again with 90 degrees, 6 units by 6 units and now lowering the height to 3 meters.



Now we need to remove parts of the parallel road.



Do not remove them all, make sure you have some road left at both ends. If you have problems removing only a part of the road, you can create a small extra road and remove the roads from here.



Now we can create the last part of the circle. Again 6 units by 6 units, 90 degrees and lowering the height with another 3 units to ground level.



And then we extend the overpass to the parallel road.



We have now created our first overpass. One last important thing to do is convert all roads of the overpass to highway ramp type of roads, because otherwise the second overpass will not fit next to this overpass.

Step 3 - The second overpass

We start with the second overpass, again with the basic road type, next to the first overpass.

The first part is again 12 units long, starts at ground level and the end is at 9 meters height.



Then we extend the road to the middle of the highway.



We extend the road at the other end, again 6 units longer then the length to the parallel road. Exactly the same as the first overpass.



Now we need to create the second circle. Since the length between both overpasses is 2 units (marked with a red line) we need to create a second circle with a radius of 8 units by 8. Again we also lower the height by 3 meters to 6 meters.



We create the second part of the circle with the same 8 units by 8, 90 degrees and lowering by 3 meters.



And now we create the last part. We going to use a part of the circle but now going the other way.

Attention, the radius needs to be 6 by 6 units now in order to connect the road to the parallel road correctly. Do not forget to lower the height again 3 meters to ground level.



We now connect the overpass to the remaining part of the parallel road.



And again we will convert all roads to the high way ramp type.

Step 4 - The finishing touches

Alsmost done. We need to do the fnishing touches.

First we create the on and off ramps on the other side. We create another road, 8 units long, in order to create another part of a circle with the same 6 unit radius. This 6 units length is marked red in the picture.



We do this at both ends.



We now remove parts of the parallel road at the other end.



And we create the connection using sectors of the circle with 6 units by 6 units, and 90 degrees.



Again convert them all to highway ramps.



Remove all remaining guideline roads.



Extend the roads at starting point by12 units.



Do this for starting roads



And now connect all the roads. Use the highway ramp type and use the bend option.



Create a connection by extending 2 or 3 units, then bend and create a connection of 20 degrees.



Do this at all ends.



Including the roads at the starting point. Make sure that all roads go in the right directions!



And voila

[DK115]

@Dog Turds: not in my steam. I can see them all. Something at your end?

[Bulldog]

Many of the step 3 photos and all of the step 4 photos are missing

[m e o w]

what mod do you use to show the units and height?

[STS]

Thanks this was super helpful and easy....

[hfok]

@hugocorp page up and page down button

[hugocorp]

No clue on how to do the overpass my roads wont elevate it just wants to connect to the highway or the guideline road just before. Anything Im missing here?

[NTMA85]

thanks !

[Eldrarak1982]

Thank you for this!

[moyad02]

wow, that's good, man. Thanks!

[Victius]

holy shit that looks good