Easting northing to latitude longitude

Eastings and northings are distances east and north, respectively, of a base point. The base point is usually a latitude and longitude, and eastings and northings are normally expressed in meters or feet. The easting and northing, however, is usually offset a particular value to make them positive and allow them to express places west … Read more

Getting GPS coordinates on Windows phone 7

Here’s a simple example: GeoCoordinateWatcher watcher; watcher = new GeoCoordinateWatcher(GeoPositionAccuracy.Default) { MovementThreshold = 20 }; watcher.PositionChanged += this.watcher_PositionChanged; watcher.StatusChanged += this.watcher_StatusChanged; watcher.Start(); private void watcher_StatusChanged(object sender, GeoPositionStatusChangedEventArgs e) { switch (e.Status) { case GeoPositionStatus.Disabled: // location is unsupported on this device break; case GeoPositionStatus.NoData: // data unavailable break; } } private void watcher_PositionChanged(object sender, GeoPositionChangedEventArgs<GeoCoordinate> … Read more

Convert from latitude, longitude to x, y

No exact solution exists There is no isometric map from the sphere to the plane. When you convert lat/lon coordinates from the sphere to x/y coordinates in the plane, you cannot hope that all lengths will be preserved by this operation. You have to accept some kind of deformation. Many different map projections do exist, … Read more

Smooth GPS data

Here’s a simple Kalman filter that could be used for exactly this situation. It came from some work I did on Android devices. General Kalman filter theory is all about estimates for vectors, with the accuracy of the estimates represented by covariance matrices. However, for estimating location on Android devices the general theory reduces to … Read more