# Topography from contour lines

**URL:** <https://discourse.mcneel.com/t/topography-from-contour-lines/109486>\
**Category:** Rhino for Windows\
**Tags:** mesh, rhino6\
**Created:** [September 29, 2020, 7:34am UTC](https://discourse.mcneel.com/t/topography-from-contour-lines/109486 "2020-09-29T07:34:35Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![e.b](https://sea3.discourse-cdn.com/mcneel/user_avatar/discourse.mcneel.com/e.b/32/250150_2.png) [@e.b](https://discourse.mcneel.com/u/e.b)\
**Post date:** [September 29, 2020, 7:34am UTC](https://discourse.mcneel.com/t/topography-from-contour-lines/109486/1 "2020-09-29T07:34:35Z")

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Hello,

I’ve only just begun using Rhino 6 and have tried to find an answer to my question online but still haven’t been able to so, so I’d greatly appreciate if someone could help me here.

I already have a file with the contour lines of an area (it’s an Adobe Illustrator file). How can I create a terrain on Rhino with these contour lines? I’ve only managed to find tutorials on how to create a random terrain surface, but getting these exact contour lines is essential to my project.

I apologise if my message is a bit unclear. Will gladly provide more information if needed. Thank you in advance.

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**Author:** ![Helvetosaur](https://sea3.discourse-cdn.com/mcneel/user_avatar/discourse.mcneel.com/helvetosaur/32/635974_2.png) [@Helvetosaur](https://discourse.mcneel.com/u/Helvetosaur)\
**Post date:** [September 29, 2020, 8:22am UTC](https://discourse.mcneel.com/t/topography-from-contour-lines/109486/2 "2020-09-29T08:22:12Z")

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Generally terrain models are made from meshes. How good they will be will depend on the quality of the contour lines, which can vary from pretty good to horrible, depending on the source.

If the contour lines are polylines, I would do the following:

1. Select all the polylines and run \_ExtractPt - will create points at all the polyline vertices. If you have a lot of really dense polylines, instead of preselecting them and running the command, run \_ExtractPt with nothing selected, and on the command line choose Output=PointCloud, then select the polylines and enter. This will create a point cloud which is much lighter and will still work with the next step.
2. With the points selected, run \_MeshPatch. That should give you a terrain mesh that goes through all the points.
3. Delete the points

You can run \_MeshPatch directly on polylines, but in my experience if the polyline data is somewhat dense, Rhino doesn’t deal with this well, and could hang. Using points the result is almost instant.

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**Author:** ![Holo](https://sea3.discourse-cdn.com/mcneel/user_avatar/discourse.mcneel.com/holo/32/496872_2.png) [@Holo](https://discourse.mcneel.com/u/Holo)\
**Post date:** [September 29, 2020, 9:21am UTC](https://discourse.mcneel.com/t/topography-from-contour-lines/109486/3 "2020-09-29T09:21:44Z")

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You can try my TerrainMesh plugin too if you like. It’s work in progress and I just released a new build today.

> [@New: TerrainMesh plugin (in alpha/beta)](https://discourse.mcneel.com/t/new-terrainmesh-plugin-in-alpha-beta/66128/107):
>
> Hi all, Please try the latest build, I included TerrainScatter so you can test it out. It needs at least one block definition in the file so it has something to scatter. And a mesh to scatter onto of course slight_smile This one expires 2020-12-31 so have fun! And as always please post some examples and/or bugs/ improvement wishes. [TerrainMesh v0,29.zip](https://discourse.mcneel.com/uploads/short-url/2JZAS8vbm8dkhN1nJ6kXYurx0Dx.zip) (18.5 KB)