/**
* Return the ListEdge in the road network which is closest to the given coordinate, within the
* given resolution
*
* @param c
* @param resolution
* @return
*/
public ListEdge getClosestEdge(Coordinate c, double resolution) {
// find the set of all edges within *resolution* of the given point
Bag objects = networkEdgeLayer.getObjectsWithinDistance(fa.createPoint(c), resolution);
if (objects == null || networkEdgeLayer.getGeometries().size() <= 0)
return null; // problem with the network edge layer
Point point = fa.createPoint(c);
// find the closest edge among the set of edges
double bestDist = resolution;
ListEdge bestEdge = null;
for (Object o : objects) {
double dist = ((MasonGeometry) o).getGeometry().distance(point);
if (dist < bestDist) {
bestDist = dist;
bestEdge =
(ListEdge) ((AttributeValue) ((MasonGeometry) o).getAttribute("ListEdge")).getValue();
}
}
// if it exists, return it
if (bestEdge != null) return bestEdge;
// otherwise return failure
else return null;
}
/**
* Return the GeoNode in the road network which is closest to the given coordinate
*
* @param c
* @return
*/
public GeoNode getClosestGeoNode(Coordinate c) {
// find the set of all nodes within *resolution* of the given point
Bag objects = networkLayer.getObjectsWithinDistance(fa.createPoint(c), resolution);
if (objects == null || networkLayer.getGeometries().size() <= 0)
return null; // problem with the network layer
// among these options, pick the best
double bestDist = resolution; // MUST be within resolution to count
GeoNode best = null;
for (Object o : objects) {
double dist = ((GeoNode) o).geometry.getCoordinate().distance(c);
if (dist < bestDist) {
bestDist = dist;
best = ((GeoNode) o);
}
}
// if there is a best option, return that!
if (best != null && bestDist == 0) return best;
// otherwise, closest GeoNode is associated with the closest Edge, so look for that!
ListEdge edge = getClosestEdge(c);
// find that edge
if (edge == null) {
edge = getClosestEdge(c, resolution * 10);
if (edge == null) return null;
}
// of that edge's endpoints, find the closer of the two and return it
GeoNode n1 = (GeoNode) edge.getFrom();
GeoNode n2 = (GeoNode) edge.getTo();
if (n1.geometry.getCoordinate().distance(c) <= n2.geometry.getCoordinate().distance(c))
return n1;
else return n2;
}
