public double DistanceTo(GeoPosition pos, Unit unit = Unit.Km)
{
var rlat1 = Math.PI * this.Latitude / 180;
var rlat2 = Math.PI * pos.Latitude / 180;
var rlon1 = Math.PI * this.Longitude / 180;
var rlon2 = Math.PI * pos.Longitude / 180;
var theta = this.Longitude - pos.Longitude;
var rtheta = Math.PI * theta / 180;
var dist = Math.Sin(rlat1) * Math.Sin(rlat2) + Math.Cos(rlat1) * Math.Cos(rlat2) * Math.Cos(rtheta);
dist = Math.Acos(dist);
dist = dist * 180 / Math.PI;
dist = dist * 60 * 1.1515;
if (unit == Unit.Km) { dist = dist * 1.609344; }
if (unit == Unit.Miles) { dist = dist * 0.8684; }
return dist;
}
public async Task<GeoPosition> GetLocationAsync()
{
Geolocator geolocator = new Geolocator();
geolocator.DesiredAccuracyInMeters = 50;
Geoposition geoposition = await geolocator.GetGeopositionAsync(
maximumAge: TimeSpan.FromMinutes(5),
timeout: TimeSpan.FromSeconds(10)
);
if (geoposition == null)
return null;
this.LastKnowPosition = new GeoPosition(geoposition.Coordinate.Latitude, geoposition.Coordinate.Longitude);
return this.LastKnowPosition;
}
public double DistanceTo(GeoPosition pos, Unit unit = Unit.Km)
{
var rlat1 = Math.PI * this.Latitude / 180;
var rlat2 = Math.PI * pos.Latitude / 180;
var rlon1 = Math.PI * this.Longitude / 180;
var rlon2 = Math.PI * pos.Longitude / 180;
var theta = this.Longitude - pos.Longitude;
var rtheta = Math.PI * theta / 180;
var dist = Math.Sin(rlat1) * Math.Sin(rlat2) + Math.Cos(rlat1) * Math.Cos(rlat2) * Math.Cos(rtheta);
dist = Math.Acos(dist);
dist = dist * 180 / Math.PI;
dist = dist * 60 * 1.1515;
if (unit == Unit.Km)
{
dist = dist * 1.609344;
}
if (unit == Unit.Miles)
{
dist = dist * 0.8684;
}
return(dist);
}