void DfsAcyclicSubgraph::callUML (
const GraphAttributes &AG,
List<edge> &arcSet)
{
const Graph &G = AG.constGraph();
// identify hierarchies
NodeArray<int> hierarchy(G,-1);
int count = 0;
int treeNum = -1;
node v;
forall_nodes(v,G)
{
if(hierarchy[v] == -1) {
int n = dfsFindHierarchies(AG,hierarchy,count,v);
if(n > 1) treeNum = count;
++count;
}
}
arcSet.clear();
// perform DFS on the directed graph formed by generalizations
NodeArray<int> number(G,0), completion(G);
int nNumber = 0, nCompletion = 0;
forall_nodes(v,G) {
if(number[v] == 0)
dfsBackedgesHierarchies(AG,v,number,completion,nNumber,nCompletion);
}
// collect all backedges within a hierarchy
// and compute outdeg of each vertex within its hierarchy
EdgeArray<bool> reversed(G,false);
NodeArray<int> outdeg(G,0);
edge e;
forall_edges(e,G) {
if(AG.type(e) != Graph::generalization || e->isSelfLoop())
continue;
node src = e->source(), tgt = e->target();
outdeg[src]++;
if (hierarchy[src] == hierarchy[tgt] &&
number[src] >= number[tgt] && completion[src] <= completion[tgt])
reversed[e] = true;
}
// topologial numbering of nodes within a hierarchy (for each hierarchy)
NodeArray<int> numV(G);
Queue<node> Q;
int countV = 0;
forall_nodes(v,G)
if(outdeg[v] == 0)
Q.append(v);
while(!Q.empty()) {
v = Q.pop();
numV[v] = countV++;
forall_adj_edges(e,v) {
node w = e->source();
if(w != v) {
if(--outdeg[w] == 0)
Q.append(w);
}
}
}
int pred0(Node *n) {
return (outdeg(n) >= 1 && indeg(n) >= 1);
}
int pred1(Edge *e) {
Node *n = &elem(e->src);
return (outdeg(n) >= 1);
}
int signature(Node *n) {
return (min(1, outdeg(n)) << 1) | min(1, indeg(n));
}
