use
Rhino.BrepClosestPoint (strObject, arrPoint [, blnFaces])
you might want to restrict to faces (blnFace = true)
and then
Check the result - Array, Element 3
use
Rhino.BrepClosestPoint (strObject, arrPoint [, blnFaces])
you might want to restrict to faces (blnFace = true)
and then
Check the result - Array, Element 3