Help Creating a Clean Topographical Surface From Polysurface

Hello, I extracted a sites topography from google earth. Its a mesh. I then made sure the mesh was ok and run MeshToNURBS. Still this games me a extremely complex polysurface.

I was wondering if I could just dup border, extract isocurves and makes a new surface with ntwroksrf.
Yet when Im asked to select the isocurves of the polysurface, the objects is not seen as a 1 poly surface but as many. So I cant extract the isocurves of the total.

Any ideas? Thanks

Heres the file if you want to see what I mean Mesto to Polysurface to Surface.3dm (1.7 MB)

Try the Patch command. Experiment with the parameters. Two possibilities for the input to Patch…

  1. Use the mesh as input to Patch. If you do this make sure the “Sample point spacing” is large enough to keep the number of sample points to a reasonable number. 100 seems to work with your current units of meters.
  2. Create a set of points at the vertices using ExtractPt and use the points as input to Patch

Your mesh is a large distance from the world origin which can cause problems with some Rhino operations. Consider moving everything closer to the world origin with an X axis offset of 30000 or 31000.

May be you can use Drape command for project a surface , or contour to extract curves , many solutions.

Drape : http://screencast.com/t/nxAbt5wg

Contour : http://screencast.com/t/25pMvf0Nv

Thank you both for the suggestions.

Very nice videos Cyver, thank you for taking the time.

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