public static HashSet <GeoObj> SearchGeoHashIndex(SessionBase session, double minLat, double minLon, double maxLat, double maxLon)
{
HashSet <GeoObj> resultSet = new HashSet <GeoObj>();
if (minLat > maxLat)
{
double t = minLat;
minLat = maxLat;
maxLat = t;
}
if (minLon > maxLon)
{
double t = minLon;
minLon = maxLon;
maxLon = t;
}
WGS84Point min = new WGS84Point(minLat, minLon);
WGS84Point max = new WGS84Point(maxLat, maxLon);
BoundingBox bbox = new BoundingBox(min, max);
GeoHashBoundingBoxQuery query = new GeoHashBoundingBoxQuery(bbox);
var btreeSet = session.AllObjects <BTreeSet <GeoObj> >().FirstOrDefault();
foreach (GeoHash hash in query.SearchHashes)
{
var itr = btreeSet.Iterator();
itr.GoTo(new GeoObj(hash.LongValue));
var current = itr.Current();
while (current != null)
{
GeoHash geoHash = GeoHash.FromLongValue(current.GeoHashAsLong);
if ((geoHash.SignificantBits >= hash.SignificantBits && geoHash.Within(hash)) || (geoHash.SignificantBits < hash.SignificantBits && hash.Within(geoHash)))
{
if (!(current.Latitude < bbox.MinLat || current.Latitude > bbox.MaxLat || current.Longitude < bbox.MinLon || current.Longitude > bbox.MaxLon))
{
resultSet.Add(current);
}
current = itr.Next();
}
else
{
break;
}
}
}
return(resultSet);
}
public static HashSet <Person> SearchGeoHashIndex(string bootDirectory, double minLat, double minLon, double maxLat, double maxLon)
{
HashSet <Person> resultSet = new HashSet <Person>();
if (minLat > maxLat)
{
double t = minLat;
minLat = maxLat;
maxLat = t;
}
if (minLon > maxLon)
{
double t = minLon;
minLon = maxLon;
maxLon = t;
}
WGS84Point min = new WGS84Point(minLat, minLon);
WGS84Point max = new WGS84Point(maxLat, maxLon);
BoundingBox bbox = new BoundingBox(min, max);
GeoHashBoundingBoxQuery query = new GeoHashBoundingBoxQuery(bbox);
using (SessionNoServer session = new SessionNoServer(bootDirectory))
{
session.BeginRead();
BTreeMap <Int64, VelocityDbList <Person> > btreeMap = session.AllObjects <BTreeMap <Int64, VelocityDbList <Person> > >().FirstOrDefault();
foreach (GeoHash hash in query.SearchHashes)
{
BTreeMapIterator <Int64, VelocityDbList <Person> > itr = btreeMap.Iterator();
itr.GoTo(hash.LongValue);
var current = itr.Current();
while (current.Value != null)
{
GeoHash geoHash = GeoHash.FromLongValue(current.Key);
if (geoHash.Within(hash) || (geoHash.SignificantBits > hash.SignificantBits && hash.Within(geoHash)))
{
foreach (Person person in current.Value)
{
resultSet.Add(person);
}
current = itr.Next();
}
else
{
break;
}
}
}
// actual geohash bounding box may be including some that are not within requested bounding box so remove such items if any
HashSet <Person> notWithin = new HashSet <Person>();
foreach (Person person in resultSet)
{
if (person.Lattitude < min.Latitude || person.Lattitude > max.Latitude || person.Longitude < min.Longitude || person.Lattitude > max.Latitude)
{
notWithin.Add(person);
}
}
foreach (Person person in notWithin)
{
resultSet.Remove(person);
}
foreach (Person person in resultSet)
{
Console.WriteLine(person.ToString() + " Lattitude: " + person.Lattitude + " Longitude: " + person.Longitude);
}
session.Commit();
}
return(resultSet);
}
