/* This appends `this` to the node `node` */
NodePtr insert(NodePtr thIs, NodePtr node)
{
int la = thIs->level; // node to be inserted
int lb = node->level; // node where insertation
assert(la < lb); // node to be inserted must have lower level then parent
//if (thIs->parent) assert(find_in_tree1(thIs) == true);
NodePtr q = NULL;
NodePtr chd = NULL;
node->move(thIs);
if (la == lb - 1)
{
node->child.push_back(thIs);
thIs->parent = node;
if (node->child.size() > MAX_NODE_SZ && node->tree->canSplit() ) // with us as additional child `node` is now too large :(
return (node->reinserted || node->parent == NULL) ? split(node) : reinsert(node);
}
else // la < lb - 1
{
chd = thIs->closest(node->child);
q = insert(thIs, chd);
}
if ((node->updateCount + 1) % UPDATE_EVERY == 0)
node->update();
else
{
if (q) node->remove(q);
node->inflate(chd);
}
return q;
}
NodePtr split(NodePtr thIs)
{
thIs->tree->increaseLevelSize(thIs->level);
NodePtr p = new Node;
NodePtr q = new Node;
p->level = q->level = thIs->level;
p->reinserted = q->reinserted = false;
p->parent = q->parent = thIs->parent;
p->tree = q->tree = thIs->tree;
p->child.resize(MAX_NODE_SZ/2);
q->child.resize(MAX_NODE_SZ/2 + 1);
assert(thIs->child.size() == MAX_NODE_SZ+1);
thIs->tree->ref = thIs->closest(thIs->child, FARTHEST); // farthest from centre
std::sort(thIs->child.begin(), thIs->child.end(), compareDist);
for (int i = 0; i < MAX_NODE_SZ+1; i++)
assert(thIs->child[i]->parent == thIs);
for (int i = 0; i < MAX_NODE_SZ/2 + 1; i++)
q->child[i] = thIs->child[i];
for (int i = MAX_NODE_SZ/2+1; i<MAX_NODE_SZ+1; i++)
p->child[i-MAX_NODE_SZ/2-1] = thIs->child[i];
for (int i = 0; i < MAX_NODE_SZ/2 + 1; i++)
q->child[i]->parent = q;
for (int i = MAX_NODE_SZ/2+1; i < MAX_NODE_SZ+1; i++)
p->child[i-MAX_NODE_SZ/2-1]->parent = p;
p->update();
q->update();
if (squaredist(thIs->centre, q->centre) < squaredist(thIs->centre, p->centre))
swap(p, q);
thIs->child = p->child; // now our children do not know we are their parents and believe p is their parent
for (int i = 0; i < thIs->child.size(); i++)
thIs->child[i]->parent = thIs;
thIs->reinserted = p->reinserted;
thIs->update();
delete p;
if (thIs == thIs->tree->root) // root split
{
// since we currently are root, make new root and make us and q its children
thIs->tree->newRoot(thIs->level + 1);
thIs->tree->root->child.push_back(thIs); thIs->parent = thIs->tree->root;
thIs->tree->root->child.push_back(q); q->parent = thIs->tree->root;
thIs->tree->root->update();
}
else
{
thIs->tree->push_front(q);
} // push_front?
return q;
}
// Each sample node has a rank randomly assigned to it, assign `node` from full tree
void Node::routeNode(NodePtr node, int level)
{
NodePtr closest;
double distMin2 = 0; // squared distance
closest = NULL;
if (tree->root == this)
findClosest(level, node, distMin2, closest);
if (closest != NULL && tree->root == this)
/* When is this point reached?
if the preceeding findClosest was called and succesed to set closest
findClosest sets closest if we are `level` or src is in our circle (=> belongs to child of ours)
=> reached if we are not `level` and node is not child of us
*/
node->route = closest->route;
else /* find closest was not successfull or we were not root */
{
if (this->level == level)
node->route = this->route;
else /* not yet right level => go down one more */
node->closest(this->child)->routeNode(node, level);
}
}
