public static <V, E extends GEdge<V>> Set<V> getDescendants(GDirectedGraph<V, E> g,
			Collection<V> vertices) {

		Set<E> edges = getEdgesFrom(g, vertices, true);
		Set<V> descendants = toVertices(edges);
		return descendants;
	}
Returns all descendants for the given vertices in the given graph.  Descendants for a given
vertex are all nodes at the outgoing side of an edge, as well as their outgoing 
vertices, etc.

@param g the graph
@param vertices the vertices for which to find descendants
@return the descendants
Ghidra/Framework/Graph/src/main/java/ghidra/graph/GraphAlgorithms.java