Need help creating a cut-away section of earth from topo mesh

Apologies if this has been answered, I searched around a little and couldn’t find an answer. I know there must be a way to do this with the native sketchup pro 2017 or some great plugin.

What I would like to do is to take my topo mesh and create faces all around the edge that go down to a flat plane below to allow my clients to better see the slope of their property when orbiting in 3D. Not a crucial thing but it does help. I’ve done it before manually but this project has a lot of edges. The result would look like a slice of cake where the icing would be the topo mesh.

Here is a simplified example of what I want:

Here is an example of what I have:

Does this make sense? Thanks for any help you may offer.

One option would be to use the Projection extension from Sketchucation to project the edges of the terrain to the rectangle below. If you use Project Lines Perpendicular to Faces and tell it to create faces, you’ll end up with what you’re after.

Hey Dave,
Thanks for the help, definitely sounds like that would do the trick. Might take me a while to select just the outside edges of the terrain (so many little triangles). But I’ll play with the settings and see what the plugin is capable of. It only lists compatibility with SU 2015 but Ill give it a go. Cheers

It works in SU2018, too.

Soften the contour edges leaving only the perimeter edges visible. Get the Select tool and double click on the surface to select the terrain and the bounding edges. Then start the extension.

If you want to keep the contours showing for your client, make a copy of the terrain before softening the edges.

@sdmitch’s Add Terrain Skirt updated for v18…

Add_Terrain_Skirt.rb (3.9 KB)



Wow! Now that is a pretty direct solution to the issue! Looks absurdly easy. Is there a version for SU 17 or with that same .rb work with 2017? I am going to upgrade to 2018 but not for another couple weeks as I wait for my new computer to be ready.

should work for any ‘Digital Globe’ + ‘Pro SU’ versions, it only changes the name of the Layer it looks for, from ‘Google Earth’ to ‘Location’…

if you create yours from scratch, you either need to change the SU Layer name to match, or edit the ruby to your Layer name…


Thank you. That looks like a great plugin. I was looking for it in the SU extension warehouse so it could install where it wanted to by itself. And I came across Eneroth Terrain Volume. Similar plugin that is a one click operation but will also calculate volume. Though once you have a skirt and make a solid I suppose that isn’t too hard anyway.

Thanks everyone for your help!

This topic was automatically closed 91 days after the last reply. New replies are no longer allowed.