ui/src/main/java/ucar/nc2/ui/point/StationRenderer.java
public ucar.unidata.geoloc.Station pickClosest(Point2D pickPt) {
    if (world2Normal == null || pickPt == null || stations.isEmpty()) return null;

    world2Normal.transform(pickPt, ptN); // work in normalized coordinate space
    StationUI closest = (StationUI) stationGrid.findClosest(ptN);

    if (debug) System.out.println("closest= " +closest);
    setSelectedStation( closest);

    return getSelectedStation();
  }
public ucar.unidata.geoloc.Station pickClosest(Point2D pickPt) {
    if (world2Normal == null || pickPt == null || stations.isEmpty()) return null;

    world2Normal.transform(pickPt, ptN); // work in normalized coordinate space
    StationUI closest = (StationUI) stationGrid.findClosest(ptN);

    if (debug) System.out.println("closest= " +closest);
    setSelectedStation( closest);

    return getSelectedStation();
  }
Find station closest to this point. Make it the "selected" station.
@param pickPt: world coordinates
@return station that contains this point, or null if none.