This applies to TopographySurface, SiteSubRegion, and the topography surface associated with a BuildingPad element. For a SiteSubRegion, this returns the points from a representation of the region’s boundary as well as the points inherited from the host TopographySurface. For the topography surface associated with a BuildingPad element, this returns the points from the sketch of this topography surface(there are no interior points for this topography surface).