Causes the value of Diagram.isTreePathToChildren to effectively choose either Destination (if true) or Source (if false).
The children of a TreeVertex are its LayoutVertex.destinationVertexes, the collection of connected LayoutEdge.toVertexes.
The tree roots are those TreeVertexes that have zero source edges.
The children of a TreeVertex are its LayoutVertex.sourceVertexes, the collection of connected LayoutEdge.fromVertexes.
The tree roots are those TreeVertexes that have zero destination edges.
This enumeration specifies how to build a tree from the TreeNetwork. Used for TreeLayout.path.
since
3.0