NmeaParser/src/SampleApp.WinDesktop/NmeaLocationDataSource.cs

88 lines
4.2 KiB
C#

// *******************************************************************************
// * Licensed under the Apache License, Version 2.0 (the "License");
// * you may not use this file except in compliance with the License.
// * You may obtain a copy of the License at
// *
// * http://www.apache.org/licenses/LICENSE-2.0
// *
// * Unless required by applicable law or agreed to in writing, software
// * distributed under the License is distributed on an "AS IS" BASIS,
// * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// * See the License for the specific language governing permissions and
// * limitations under the License.
// ******************************************************************************
using System;
using System.Threading.Tasks;
using Esri.ArcGISRuntime.Geometry;
using NmeaParser.Gnss;
namespace SampleApp.WinDesktop
{
public class NmeaLocationDataSource : Esri.ArcGISRuntime.Location.LocationDataSource
{
private static SpatialReference wgs84_ellipsoidHeight = SpatialReference.Create(4326, 115700);
private readonly GnssMonitor m_gnssMonitor;
private readonly bool m_startStopDevice;
private double lastCourse = 0; // Course can fallback to NaN, but ArcGIS Datasource don't allow NaN course, so we cache last known as a fallback
/// <summary>
/// Initializes a new instance of the <see cref="NmeaLocationDataSource"/> class.
/// </summary>
/// <param name="device">The NMEA device to monitor</param>
/// <param name="startStopDevice">Whether starting this datasource also controls the underlying NMEA device</param>
public NmeaLocationDataSource(NmeaParser.NmeaDevice device, bool startStopDevice = true) : this(new GnssMonitor(device), startStopDevice)
{
}
/// <summary>
/// Initializes a new instance of the <see cref="NmeaLocationDataSource"/> class.
/// </summary>
/// <param name="monitor">The NMEA device to monitor</param>
/// <param name="startStopDevice">Whether starting this datasource also controls the underlying NMEA device</param>
public NmeaLocationDataSource(NmeaParser.Gnss.GnssMonitor monitor, bool startStopDevice = true)
{
if (monitor == null)
throw new ArgumentNullException(nameof(monitor));
this.m_gnssMonitor = monitor;
m_startStopDevice = startStopDevice;
}
protected async override Task OnStartAsync()
{
m_gnssMonitor.LocationChanged += OnLocationChanged;
m_gnssMonitor.LocationLost += OnLocationChanged;
if (m_startStopDevice && !this.m_gnssMonitor.Device.IsOpen)
await this.m_gnssMonitor.Device.OpenAsync();
if (m_gnssMonitor.IsFixValid)
OnLocationChanged(this, EventArgs.Empty);
}
protected override Task OnStopAsync()
{
m_gnssMonitor.LocationChanged -= OnLocationChanged;
m_gnssMonitor.LocationLost -= OnLocationChanged;
if(m_startStopDevice)
return m_gnssMonitor.Device.CloseAsync();
else
return Task.CompletedTask;
}
private void OnLocationChanged(object sender, EventArgs e)
{
if (double.IsNaN(m_gnssMonitor.Longitude) || double.IsNaN(m_gnssMonitor.Latitude)) return;
if (!double.IsNaN(m_gnssMonitor.Course))
lastCourse = m_gnssMonitor.Course;
UpdateLocation(new Esri.ArcGISRuntime.Location.Location(
timestamp: null,
position: !double.IsNaN(m_gnssMonitor.Altitude) ? new MapPoint(m_gnssMonitor.Longitude, m_gnssMonitor.Latitude, m_gnssMonitor.Altitude, wgs84_ellipsoidHeight) : new MapPoint(m_gnssMonitor.Longitude, m_gnssMonitor.Latitude, SpatialReferences.Wgs84),
horizontalAccuracy: m_gnssMonitor.HorizontalError,
verticalAccuracy: m_gnssMonitor.VerticalError,
velocity: double.IsNaN(m_gnssMonitor.Speed) ? 0 : m_gnssMonitor.Speed * 0.51444444,
course: lastCourse,
!m_gnssMonitor.IsFixValid));
}
}
}