Road On Terrain

Hi, I want to replicate in the rhino a similar road building method that you can see in this SketchUp video:

So I started with the sweep option to make the road, bo I don’t know how to make an offset extrude in a shape that is now flat, to make the side slopes.

what I want:

Any hints or an alternative method?


If it were me, I’d probably do a sweep to create the bottom surface of the road, then duplicate that surface and move it up to where you want the top of the road. Then I’d select nothing, select Split and Isocurve option. Then I’d split that upper surface wherever you want to. Delete what you don’t need then loft to create the edges of the road.

Actually, I might not use sweep - things get twisty with sweep. I’d probably draw both sides of the road from the top view, modify them in z to get them where they should be, then loft between them. But if sweep is doing what you want then do that.

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ExtrudeTapered, maybe?
HTH, Jakob

Or you could just do the slanted sides as part of the sweep.


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Hi @jakubaken,

You could use Lands Design to do this, take a look! Here you have a tutorial where we speak about the laPath command which will be useful for your task:



Thx you all for the tips, problem solved :slight_smile:

Hi all,

It seems that this issue has been addressed, but for others looking to do similar things I wanted to mention Topo Kit - it’s a grasshopper plugin designed to handle issues exactly like this. It can be used to quickly import topographic data, make a model, and for an example like this roadway, use a Variable Sloped Path component (which relies on just one curve and a set of parameters of your choosing) to instantly grade the road to your specifications.

It also has additional support for curbs, walls, and other landscape features which may be helpful here depending on the level of detail you’re hoping to achieve with this model. This video is a helpful guide to getting started.