/**
* Used by add(). Chooses a leaf to add the rectangle to.
*/
private Node <T> chooseNode(Rectangle r, int level)
{
// CL1 [Initialize] Set N to be the root node
Node <T> n = getNode(rootNodeId);
parents.Clear();
parentsEntry.Clear();
// CL2 [Leaf check] If N is a leaf, return N
while (true)
{
if (n.level == level)
{
return(n);
}
// CL3 [Choose subtree] If N is not at the desired level, let F be the entry in N
// whose rectangle FI needs least enlargement to include EI. Resolve
// ties by choosing the entry with the rectangle of smaller area.
double leastEnlargement = n.getEntry(0).enlargement(r);
int index = 0; // index of rectangle in subtree
for (int i = 1; i < n.entryCount; i++)
{
Rectangle tempRectangle = n.getEntry(i);
double tempEnlargement = tempRectangle.enlargement(r);
if ((tempEnlargement < leastEnlargement) ||
((tempEnlargement == leastEnlargement) &&
(tempRectangle.area() < n.getEntry(index).area())))
{
index = i;
leastEnlargement = tempEnlargement;
}
}
parents.Push(n.nodeId);
parentsEntry.Push(index);
// CL4 [Descend until a leaf is reached] Set N to be the child Node<T>
// pointed to by Fp and repeat from CL2
n = getNode(n.ids[index]);
}
}
