private void buildFlightPath()
{
// Use geometry engine to create a circle around the center of the scene
Geometry circle = GeometryEngine.EllipseGeodesic(new GeodesicEllipseParameters(centerPoint, 1700, 1700));
// Create a path around the perimeter of the circle
routePath = (Polyline)GeometryEngine.Boundary(circle);
// Store the length of the route for use later
routeLength = GeometryEngine.Length(routePath);
}