HOWTO create 3D TIN

This is a micro-howto about how to create 3D TINs from 3D vector points. The resulting TIN is saved as a DXF file, that can be imported into GRASS or used with CAD programs.

- NOTE: this was only tested on Linux machines!

First you need to install Paraview (http://www.paraview.org) and MeshLab (http://meshlab.sourceforge.net/).

Then,

1 - Export your 3d points as a VTK file;

2 - In Paraview, open the vtk file, click on Apply, then go to Filters-Alphabetical-Delaunay 2D (need to click apply again). click on the name of the just-created mesh and go to file-save data. Save it as a PLY file.

3 - Open the PLY in MEshLab and save as a DXF. If you open the dxf in a text editor, you will see the lovely 3DFACE. :)

If imported it back into GRASS, it will be imported as FACES.

good luck!