/** @see com.infomatiq.jsi.SpatialIndex#nearest(Point, IntProcedure, float) */
public void nearest(Point p, IntProcedure v, float furthestDistance) {
Node rootNode = getNode(rootNodeId);
nearest(p, rootNode, furthestDistance);
visitProc.setProcedure(v);
nearestIds.forEach(visitProc);
nearestIds.clear();
}
/**
* Recursively searches the tree for the nearest entry. Other queries call execute() on an
* IntProcedure when a matching entry is found; however nearest() must store the entry Ids as it
* searches the tree, in case a nearer entry is found. Uses the member variable nearestIds to
* store the nearest entry IDs.
*
* <p>[x] TODO rewrite this to be non-recursive?
*/
private float nearest(Point p, Node n, float nearestDistance) {
for (int i = 0; i < n.entryCount; i++) {
float tempDistance = n.entries[i].distance(p);
if (n.isLeaf()) { // for leaves, the distance is an actual nearest distance
if (tempDistance < nearestDistance) {
nearestDistance = tempDistance;
nearestIds.clear();
}
if (tempDistance <= nearestDistance) {
nearestIds.add(n.ids[i]);
}
} else { // for index nodes, only go into them if they potentially could have
// a rectangle nearer than actualNearest
if (tempDistance <= nearestDistance) {
// search the child node
nearestDistance = nearest(p, getNode(n.ids[i]), nearestDistance);
}
}
}
return nearestDistance;
}