...
It could be done selecting a checkbox when importing or after with process commands (Mescape Meshing ConnectPoints CreateSurfaces)
Delaunay triangulated surfaces
- Create a single smooth NURBS surface approximating the cloud of points
Geometry->Create->NURBS surface->By points
...
Single NURBS surface approximated
- Re-construct surfaces from triangle mesh
First Import xyz as nodes (not points!), connecting with triangles
Files->Import->XZY nodes...
and then
Geometry->Create->Geometry from mesh->NURBS patches
This tool is not recommended in general, because it is not robust enough. It try to create smooth curves joining sharp edges, find closed regions and create smooth NURBS surfaces bounded by the curves and approximating the inner shape based on the shape of the mesh.
Reconstructed NURBS surfaces