/**
* Derive the split components of this palm tree. This method is taken from the paper of Gutwenger
* and Mutzel "A linear time implementation of SPQR trees".
*
* @param v
*/
public List<SplitComponent> determineSplitComponents() {
try {
this.preparePathSearch();
this.tStackPushEos();
// System.out.println("NEW NUMBERS: " + NEWNUM);
// System.out.println("ND: " + ND);
// System.out.println("LOW1:" + LOWPT1);
// System.out.println("LOW2:" + LOWPT2);
// System.out.println("ORD ADJ: " + ADJ);
// System.out.println("--------------------------");
this.pathSearch(this.m_start);
SplitComponent newCmp = new SplitComponent();
if (ESTACK.size() == 1) newCmp.setType(ComponentType.TRIVIAL);
else if (ESTACK.size() >= 4) newCmp.setType(ComponentType.TRICONNECTED);
else newCmp.setType(ComponentType.POLYGON);
while (!ESTACK.empty()) {
newCmp.add(ESTACK.pop());
}
// System.err.println("COMP: " + newCmp);
//
this.splitComponents.add(newCmp);
this.splitComponents.addAll(graph.getMultipleEdgeBonds());
// System.err.println("\n\nALL COMPONENTS: ");
// System.err.println(this.splitComponents);
// System.err.println("\n\n");
} catch (Exception e) {
e.printStackTrace();
}
return this.splitComponents;
}
/**
* Derive the split components of this palm tree. This method is taken from the paper of Gutwenger
* and Mutzel "A linear time implementation of SPQR trees". UPDATE: This is more taken from the
* OGDF C++ implementation since the paper hides a lot of necessary information.
*
* @param v the start node
*/
private void pathSearch(Node v) {
// System.err.println("BEGIN pS(" + v + ");" );
int vnum = NEWNUM.get(v);
int wnum;
int y = 0;
int a, b;
IterableAdjacencyList adj = ADJ.get(v);
adj.reset();
Node w;
int outv = adj.size();
while (adj.hasNext()) {
Edge e = adj.next();
// System.err.println("CURRENT EDGE: " + e);
w = e.getTarget();
wnum = NEWNUM.get(w);
if (TYPE.get(e).equals(ArcType.TREE)) {
if (START.get(e)) {
y = 0;
if (tStackGetTopA() > LOWPT1.get(w)) {
do {
y = Math.max(y, tStackGetTopH());
b = tStackGetTopB();
TSTACK.pop();
} while (tStackGetTopA() > LOWPT1.get(w));
Triple t = new Triple(Math.max(y, wnum + ND.get(w) - 1), LOWPT1.get(w), b);
TSTACK.push(t);
// System.err.println("TSTACK push 1: " + t);
} else {
Triple t = new Triple(wnum + ND.get(w) - 1, LOWPT1.get(w), vnum);
TSTACK.push(t);
// System.err.println("TSTACK push 2: " + t);
}
tStackPushEos();
}
pathSearch(w);
ESTACK.push(TREE_ARC.get(w));
// System.err.println("TSTACK: " + TSTACK);
// System.err.println("CURRENT VNUM: " + vnum);
// System.err.println("DEG(w): " + DEGREE.get(w));
// check for type 2 pairs
while (vnum != 1
&& ((tStackGetTopA() == vnum)
|| (DEGREE.get(w) == 2 && NEWNUM.get(firstChild(w)) > wnum))) {
a = tStackGetTopA();
b = tStackGetTopB();
Edge eVirt = null;
if (a == vnum && FATHER.get(NODEAT[b]) == NODEAT[a]) {
TSTACK.pop();
} else {
Edge e_ab = null;
Node x = null;
// System.err.println("W: " + w);
// System.err.println("DEG(W): " + DEGREE.get(w) );
if (DEGREE.get(w) == 2 && NEWNUM.get(firstChild(w)) > wnum) {
// System.err.println("FOUND type-2 pair " + v + " , " +
// firstChild(w));
// System.err.println("ESTACK: " + ESTACK);
Edge e1 = ESTACK.pop();
Edge e2 = ESTACK.pop();
ADJ.get(e2.getSource()).remove(e2);
ADJ.get(e1.getSource()).remove(e1);
x = e2.getTarget();
// System.err.println("X:" + x);
decrementDegree(x);
decrementDegree(v);
eVirt = new Edge(0, v, x);
eVirt.setVirtual(true);
SplitComponent sc = new SplitComponent();
sc.add(e1);
sc.add(e2);
sc.add(eVirt);
sc.setType(ComponentType.POLYGON);
splitComponents.add(sc);
// System.err.println("COMP1: " + sc);
// System.err.println("ESTACK: " + ESTACK);
if (!ESTACK.empty()
&& ESTACK.peek().getSource() == x
&& ESTACK.peek().getTarget() == v) {
e_ab = ESTACK.pop();
ADJ.get(x).remove(e_ab);
delHigh(e_ab);
}
} else {
// System.err.println("ESTACK: " + ESTACK);
// System.err.println("FOUND type-2 pair " + NODEAT[a] + "
// , " + NODEAT[b]);
int h = TSTACK.peek().h;
TSTACK.pop();
SplitComponent sc = new SplitComponent();
while (true) {
Edge xy = ESTACK.peek();
x = xy.getSource();
if (!(a <= NEWNUM.get(x)
&& NEWNUM.get(x) <= h
&& a <= NEWNUM.get(xy.getTarget())
&& NEWNUM.get(xy.getTarget()) <= h)) {
break;
}
if ((NEWNUM.get(x) == a && NEWNUM.get(xy.getTarget()) == b)
|| (NEWNUM.get(xy.getTarget()) == a && NEWNUM.get(x) == b)) {
e_ab = ESTACK.pop();
ADJ.get(e_ab.getSource()).remove(e_ab);
delHigh(e_ab);
} else {
Edge eh = ESTACK.pop();
if (e != eh) {
ADJ.get(eh.getSource()).remove(eh);
delHigh(eh);
}
sc.add(eh);
decrementDegree(x);
decrementDegree(xy.getTarget());
}
}
eVirt = new Edge(0, NODEAT[a], NODEAT[b]);
eVirt.setVirtual(true);
sc.add(eVirt);
sc.finishTriconnectedOrPolygon();
splitComponents.add(sc);
// System.err.println("COMP2: " + sc);
x = NODEAT[b];
}
if (e_ab != null) {
SplitComponent sc = new SplitComponent();
sc.setType(ComponentType.BOND);
sc.add(e_ab);
sc.add(eVirt);
eVirt = new Edge(0, v, x);
eVirt.setVirtual(true);
sc.add(eVirt);
splitComponents.add(sc);
// System.err.println("COMP: " + sc);
decrementDegree(x);
decrementDegree(v);
}
ESTACK.push(eVirt);
adj.insert(eVirt);
START.put(eVirt, START.get(e));
incrementDegree(x);
incrementDegree(v);
FATHER.put(x, v);
TREE_ARC.put(x, eVirt);
TYPE.put(eVirt, ArcType.TREE);
w = x;
wnum = NEWNUM.get(w);
}
}
// check for type 1 pair
if (LOWPT2.get(w) >= vnum
&& LOWPT1.get(w) < vnum
&& (FATHER.get(v) != m_start || outv >= 2)) {
// System.err.println( "Found type-1 pair( " + v + "," + NODEAT[
// LOWPT1.get(w) ] + ")");
SplitComponent c = new SplitComponent();
Edge xy = null;
int xnum, ynum;
// System.err.println("ESTACK: " + ESTACK);
while (!ESTACK.isEmpty()) {
xy = ESTACK.peek();
xnum = NEWNUM.get(xy.getSource());
ynum = NEWNUM.get(xy.getTarget());
if (!((wnum <= xnum && xnum < wnum + ND.get(w))
|| (wnum <= ynum && ynum < wnum + ND.get(w)))) {
break;
}
ESTACK.pop();
c.add(xy);
delHigh(xy);
decrementDegree(xy.getSource());
ADJ.get(xy.getSource()).remove(xy);
this.graphCopy.edges.remove(xy);
decrementDegree(xy.getTarget());
}
Edge eVirt = new Edge(0, v, NODEAT[LOWPT1.get(w)]);
eVirt.setVirtual(true);
this.graphCopy.addEdge(eVirt);
c.add(eVirt);
c.finishTriconnectedOrPolygon();
splitComponents.add(c);
// System.err.println("COMP: " + c);
// System.out.println("STACK HERE: " + ESTACK);
if (
/*!ESTACK.isEmpty() && */ (xy.getSource() == v && xy.getTarget() == NODEAT[LOWPT1.get(w)])
|| (xy.getTarget() == v && xy.getSource() == NODEAT[LOWPT1.get(w)])) {
SplitComponent sc = new SplitComponent();
sc.setType(ComponentType.BOND);
Edge eh = ESTACK.pop();
if (eh != e) {
ADJ.get(eh.getSource()).remove(eh);
}
sc.add(eh);
ADJ.get(eh.getSource()).remove(eh);
this.graphCopy.edges.remove(eh);
decrementDegree(eh.getSource());
decrementDegree(eh.getTarget());
sc.add(eVirt);
eVirt = new Edge(0, v, NODEAT[LOWPT1.get(w)]);
eVirt.setVirtual(true);
// BLOCK IN OGDF left out --> m_IN_HIGH
sc.add(eVirt);
splitComponents.add(sc);
// System.err.println("COMP: " + sc );
}
if ((NODEAT[LOWPT1.get(w)] != FATHER.get(v))) {
ESTACK.push(eVirt);
adj.insert(eVirt);
START.put(eVirt, false);
TYPE.put(eVirt, ArcType.FROND);
if (high(NODEAT[LOWPT1.get(w)]) < vnum) HIGHPT.get(NODEAT[LOWPT1.get(w)]).add(0, vnum);
incrementDegree(v);
incrementDegree(NODEAT[LOWPT1.get(w)]);
} else {
adj.remove(e); // BLOCK from OGDF --> Adj.del(it);
SplitComponent sc = new SplitComponent();
sc.setType(ComponentType.BOND);
sc.add(eVirt);
Edge eh = TREE_ARC.get(v);
sc.add(eh);
splitComponents.add(sc);
ADJ.get(eh.getSource()).remove(eh);
eVirt = new Edge(0, NODEAT[LOWPT1.get(w)], v);
eVirt.setVirtual(true);
sc.add(eVirt);
// System.err.println("COMP: " + sc);
TYPE.put(eVirt, ArcType.TREE);
// System.out.println("INSERT HERE into " + eh.getSource() +
// "TARGET: " + eh.getTarget());
ADJ.get(eh.getSource()).insert(eVirt);
TREE_ARC.put(v, eVirt);
START.put(eVirt, START.get(eh));
}
}
if (START.get(e)) {
while (tStackNotEos()) {
TSTACK.pop();
}
TSTACK.pop();
}
while (tStackNotEos()
&& tStackGetTopA() != vnum
&& tStackGetTopB() != vnum
&& high(v) > tStackGetTopH()) {
TSTACK.pop();
}
outv--;
} else { // frond arc
// System.err.println("TSTACK 2: " + TSTACK);
if (START.get(e)) {
y = 0;
if (tStackGetTopA() > LOWPT1.get(w)) {
do {
y = Math.max(y, tStackGetTopH());
b = tStackGetTopB();
TSTACK.pop();
} while (tStackGetTopA() > LOWPT1.get(w));
Triple t = new Triple(y, wnum, b);
TSTACK.push(t);
// System.err.println("TSTACK push3: " + t);
} else {
Triple t = new Triple(vnum, wnum, vnum);
TSTACK.push(new Triple(vnum, wnum, vnum));
// System.err.println("TSTACK push4: " + t);
}
// tStackPushEos();
}
// BLOCK FROM PAPER left out --> if ( w = parent(v) )
ESTACK.push(e);
}
}
// System.err.println("END pS(" + v + ");" );
}