docs: protected double distanceToHrect(KDTreeNode node, Instance x) throws Exception {
      double distance = 0.0;
  
      Instance closestPoint = (Instance)x.copy();
      boolean inside;
      inside = clipToInsideHrect(node, closestPoint);
      if (!inside)
        distance = m_EuclideanDistance.distance(closestPoint, x);
      return distance;
    }