You can view the layered, hierarchical subsystem structure rooted at a node by creating an overview. The hierarchy is presented in an overview window. To produce an overview:
A new Overview window appears, presenting the tree-like subsystem structure below the specified root node The root node is at the top of the tree in the new window. An Overview window presents a vertical ``slice'' of the hierarchy. The arcs that span levels in the hierarchy are known as level arcs. For clarity, the arcs within a level and the node labels are filtered in an Overview window.
Tip: It's useful to resize this window and place it in a corner of the screen while you work.
Note: Overview window s do not support graph modifying operations.