// Performs a planarity test on a biconnected component
// of G. numbering contains an st-numbering of the component.
void FastPlanarSubgraph::planarize(
const Graph &G,
NodeArray<int> &numbering,
List<edge> &delEdges)
{
node v;
NodeArray<SListPure<PlanarLeafKey<whaInfo*>* > > inLeaves(G);
NodeArray<SListPure<PlanarLeafKey<whaInfo*>* > > outLeaves(G);
Array<node> table(G.numberOfNodes()+1);
forall_nodes(v,G)
{
edge e;
forall_adj_edges(e,v)
{
if (numbering[e->opposite(v)] > numbering[v])
// sideeffect: ignores selfloops
{
PlanarLeafKey<whaInfo*>* L = OGDF_NEW PlanarLeafKey<whaInfo*>(e);
inLeaves[v].pushFront(L);
}
}
table[numbering[v]] = v;
}
// Performs a planarity test on a biconnected component
// of G. numbering contains an st-numbering of the component.
bool CconnectClusterPlanar::doTest(
Graph &G,
NodeArray<int> &numbering,
cluster &cl,
node superSink,
EdgeArray<edge> &edgeTable)
{
bool cPlanar = true;
NodeArray<SListPure<PlanarLeafKey<IndInfo*>* > > inLeaves(G);
NodeArray<SListPure<PlanarLeafKey<IndInfo*>* > > outLeaves(G);
Array<node> table(G.numberOfNodes()+1);
for(node v : G.nodes)
{
for (adjEntry adj : v->adjEntries) {
if (numbering[adj->twinNode()] > numbering[v])
//sideeffect: loops are ignored
{
PlanarLeafKey<IndInfo*>* L = OGDF_NEW PlanarLeafKey<IndInfo*>(adj->theEdge());
inLeaves[v].pushFront(L);
}
}
table[numbering[v]] = v;
}
for(node v : G.nodes)
{
for (PlanarLeafKey<IndInfo*>* L : inLeaves[v])
{
outLeaves[L->userStructKey()->opposite(v)].pushFront(L);
}
}
PlanarPQTree* T = new PlanarPQTree();
T->Initialize(inLeaves[table[1]]);
for (int i = 2; i < G.numberOfNodes(); i++)
{
if (T->Reduction(outLeaves[table[i]]))
{
T->ReplaceRoot(inLeaves[table[i]]);
T->emptyAllPertinentNodes();
}
else
{
cPlanar = false;
break;
}
}
if (cPlanar && cl && superSink)
{
// Keep the PQTree to construct a wheelgraph
// Replace the edge stored in the keys of T
// by the original edges.
// Necessary, since the edges currently in T
// correspond to a graph that mirrors a biconnected
// component and thus is deallocated
int n = G.numberOfNodes();
for (PlanarLeafKey<IndInfo*>* info : outLeaves[table[n]])
{
PQLeafKey<edge,IndInfo*,bool>* key = (PQLeafKey<edge,IndInfo*,bool>*) info;
key->m_userStructKey = edgeTable[key->m_userStructKey];
}
m_clusterPQTree[cl] = T;
}
else //if (cPlanar)
delete T;
// Cleanup
for(node v : G.nodes)
{
if (v != superSink || !cPlanar)
{
while (!outLeaves[v].empty())
{
PlanarLeafKey<IndInfo*>* L = outLeaves[v].popFrontRet();
delete L;
}
}
}
return cPlanar;
}