set oRoot = Application.ActiveProject.ActiveScene.Root
set oGrid = oRoot.AddGeometry( "Grid","MeshSurface" )
set oCluster = oGrid.ActivePrimitive.Geometry.AddCluster( siVertexCluster, "VextexClusterOnGrid", array(4,5,6) )
Application.LogMessage "cluster is a kind of poly? " & oCluster.IsKindOf( "poly" )
Application.LogMessage "cluster is a kind of pnt? " & oCluster.IsKindOf( "pnt" )
Application.LogMessage "cluster is a kind of edge? " & oCluster.IsKindOf( "edge" )
set oCube = oRoot.AddGeometry( "Cube", "MeshSurface" )
if oCube.IsKindOf( "Cube" ) then
        Application.LogMessage oCube.Name & " is a cube object"
end if
if oCube.IsKindOf( "polymsh" ) then
        Application.LogMessage oCube.Name & " is a surface mesh object"
end if