inspection point cloud on DTM

The SurfaceModeller transformer allows you to drape features on the surface model created. Send your points into the DRAPE_FEATURES port. The elevated points will be output from the DRAPED_FEATURES port.

Yes I tryied it, but it doesn't works.

 

I put one point cloud as input from points/lines (wich is the ground) and one point cloud as drapped features (wich is vegetation).

 

And as output for drapped features I put one point cloud too. I want XY from the vegetation and Z interpoled.

 

 

what kind of features must I use?

 

thanks