/// <summary>
/// 据某点的距离（单位：英里）
/// </summary>
/// <param name="point"></param>
/// <returns></returns>
public double MilesTo(LCGeoPoint point)
{
if (point == null)
{
throw new ArgumentNullException(nameof(point));
}
return(RadiansTo(point) * 3958.8);
}
/// <summary>
/// 据某点的距离（单位：千米）
/// </summary>
/// <param name="point"></param>
/// <returns></returns>
public double KilometersTo(LCGeoPoint point)
{
if (point == null)
{
throw new ArgumentNullException(nameof(point));
}
return(RadiansTo(point) * 6371.0);
}
public LCSearchSortBuilder WhereNear(string key, LCGeoPoint point,
string order = null, string mode = null, string unit = null)
{
fields.Add(new Dictionary <string, object> {
{ "_geo_distance", new Dictionary <string, object> {
{ key, new Dictionary <string, object> {
{ "lat", point.Latitude },
{ "lon", point.Longitude }
} },
{ "order", order ?? "asc" },
{ "mode", mode ?? "avg" },
{ "unit", unit ?? "km" }
} }
});
return(this);
}
/// <summary>
/// 据某点的距离（单位：弧度）
/// </summary>
/// <param name="point"></param>
/// <returns></returns>
public double RadiansTo(LCGeoPoint point)
{
if (point == null)
{
throw new ArgumentNullException(nameof(point));
}
double d2r = Math.PI / 180.0;
double lat1rad = Latitude * d2r;
double long1rad = Longitude * d2r;
double lat2rad = point.Latitude * d2r;
double long2rad = point.Longitude * d2r;
double deltaLat = lat1rad - lat2rad;
double deltaLong = long1rad - long2rad;
double sinDeltaLatDiv2 = Math.Sin(deltaLat / 2);
double sinDeltaLongDiv2 = Math.Sin(deltaLong / 2);
double a = sinDeltaLatDiv2 * sinDeltaLatDiv2 +
Math.Cos(lat1rad) * Math.Cos(lat2rad) * sinDeltaLongDiv2 * sinDeltaLongDiv2;
a = Math.Min(1.0, a);
return(2 * Math.Sin(Math.Sqrt(a)));
}
/// <summary>
/// 在坐标区域内
/// </summary>
/// <param name="key"></param>
/// <param name="southwest"></param>
/// <param name="northeast"></param>
/// <returns></returns>
public LCQuery <T> WhereWithinGeoBox(string key, LCGeoPoint southwest, LCGeoPoint northeast)
{
condition.WhereWithinGeoBox(key, southwest, northeast);
return(this);
}
/// <summary>
/// 相邻
/// </summary>
/// <param name="key"></param>
/// <param name="point"></param>
/// <returns></returns>
public LCQuery <T> WhereNear(string key, LCGeoPoint point)
{
condition.WhereNear(key, point);
return(this);
}