Returns the visibility status of the node.
getVisibility()
Return Value
0 – Not visible
1 – Visible
2 – Special case for groups and layer nodes: only some of the child nodes are visible.
Remarks
Most of the nodes have a visual representation on the terrain (e.g., polygons). This method provides a way to check their visibility status on the terrain. When checking the visibility status of a group node that only some of its children are visible, the return value is 2.