Class MapPolylineTreeSet<P extends MapPolyline>

    • Constructor Detail

      • MapPolylineTreeSet

        public MapPolylineTreeSet()
        Create an empty tree.
      • MapPolylineTreeSet

        public MapPolylineTreeSet​(double boundsX,
                                  double boundsY,
                                  double boundsWidth,
                                  double boundsHeight)
        Constructor.
        Parameters:
        boundsX - is the bounds of the scene.
        boundsY - is the bounds of the scene.
        boundsWidth - is the bounds of the scene.
        boundsHeight - is the bounds of the scene.
      • MapPolylineTreeSet

        public MapPolylineTreeSet​(Rectangle2afp<?,​?,​?,​?,​?,​?> bounds)
        Constructor.
        Parameters:
        bounds - are the bounds of the scene stored inside this tree.
    • Method Detail

      • add

        public boolean add​(P polyline,
                           double precision,
                           OutputParameter<P> firstNeighbour,
                           OutputParameter<P> secondNeighbour)
        Description copied from interface: GISPolylineSet
        Add the selected polyline inside the tree and replies the two nearest polylines that are already inside the tree.
        Specified by:
        add in interface GISPolylineSet<P extends MapPolyline>
        Parameters:
        polyline - is the polyline to add
        precision - is the precision (in meters) used to detect the neighbours.
        firstNeighbour - is one of the two nearest polylines that could be connected to the new segment.
        secondNeighbour - is one of the two nearest polylines that could be connected to the new segment.
        Returns:
        true if successfully added, false otherwise
      • getNearestEnd

        @Pure
        public final P getNearestEnd​(Point2D<?,​?> position)
        Replies the object that has the nearest end to the specified point. The nearest neighbor (NN) algorithm, to find the NN to a given target point not in the tree, relies on the ability to discard large portions of the tree by performing a simple test. To perform the NN calculation, the tree is searched in a depth-first fashion, refining the nearest distance. First the root node is examined with an initial assumption that the smallest distance to the next point is infinite. The subdomain (right or left), which is a hyperrectangle, containing the target point is searched. This is done recursively until a final minimum region containing the node is found. The algorithm then (through recursion) examines each parent node, seeing if it is possible for the other domain to contain a point that is closer. This is performed by testing for the possibility of intersection between the hyperrectangle and the hypersphere (formed by target node and current minimum radius). If the rectangle that has not been recursively examined yet does not intersect this sphere, then there is no way that the rectangle can contain a point that is a better nearest neighbour. This is repeated until all domains are either searched or discarded, thus leaving the nearest neighbour as the final result. In addition to this one also has the distance to the nearest neighbour on hand as well. Finding the nearest point is an O(logN) operation.
        Specified by:
        getNearestEnd in interface GISPolylineSet<P extends MapPolyline>
        Parameters:
        position - is the position from which the nearest primitive must be replied.
        Returns:
        the nearest element or null if none.
        See Also:
        GISPolylineSet.getNearestEnd(double, double)
      • getNearestEnd

        @Pure
        public P getNearestEnd​(double x,
                               double y)
        Replies the object that has the nearest end to the specified point. The nearest neighbor (NN) algorithm, to find the NN to a given target point not in the tree, relies on the ability to discard large portions of the tree by performing a simple test. To perform the NN calculation, the tree is searched in a depth-first fashion, refining the nearest distance. First the root node is examined with an initial assumption that the smallest distance to the next point is infinite. The subdomain (right or left), which is a hyperrectangle, containing the target point is searched. This is done recursively until a final minimum region containing the node is found. The algorithm then (through recursion) examines each parent node, seeing if it is possible for the other domain to contain a point that is closer. This is performed by testing for the possibility of intersection between the hyperrectangle and the hypersphere (formed by target node and current minimum radius). If the rectangle that has not been recursively examined yet does not intersect this sphere, then there is no way that the rectangle can contain a point that is a better nearest neighbour. This is repeated until all domains are either searched or discarded, thus leaving the nearest neighbour as the final result. In addition to this one also has the distance to the nearest neighbour on hand as well. Finding the nearest point is an O(logN) operation.
        Specified by:
        getNearestEnd in interface GISPolylineSet<P extends MapPolyline>
        Parameters:
        x - is the position from which the nearest primitive must be replied.
        y - is the position from which the nearest primitive must be replied.
        Returns:
        the nearest element or null if none.