FollowMe.cs

using System;
using System.Windows.Forms;
using MissionPlanner.Comms;
using System.Globalization;
using MissionPlanner.Controls;
using MissionPlanner.Utilities;
using System.IO;
using MissionPlanner.ArduPilot;

namespace MissionPlanner
{
    public partial class FollowMe : Form
    {
        System.Threading.Thread t12;
        static bool threadrun = false;
        static FollowMe Instance;
        static internal SerialPort comPort = new SerialPort();
        static internal PointLatLngAlt lastgotolocation = new PointLatLngAlt(0, 0, 0, "Goto last");
        static internal PointLatLngAlt gotolocation = new PointLatLngAlt(0, 0, 0, "Goto");
        static internal int intalt = 100;
        static float updaterate = 0.5f;

        public FollowMe()
        {
            Instance = this;

            InitializeComponent();

            CMB_serialport.DataSource = SerialPort.GetPortNames();

            CMB_updaterate.SelectedItem = updaterate;

            if (threadrun)
            {
                BUT_connect.Text = Strings.Stop;
                CMB_baudrate.Text = comPort.BaudRate.ToString();
                CMB_serialport.Text = comPort.PortName;
                CMB_updaterate.Text = updaterate.ToString();
            }

            MissionPlanner.Utilities.Tracking.AddPage(
                System.Reflection.MethodBase.GetCurrentMethod().DeclaringType.ToString(),
                System.Reflection.MethodBase.GetCurrentMethod().Name);
        }

        private void BUT_connect_Click(object sender, EventArgs e)
        {
            if (comPort.IsOpen)
            {
                threadrun = false;
                comPort.Close();
                BUT_connect.Text = Strings.Connect;
            }
            else
            {
                try
                {
                    comPort.PortName = CMB_serialport.Text;
                }
                catch
                {
                    CustomMessageBox.Show(Strings.InvalidPortName, Strings.ERROR);
                    return;
                }
                try
                {
                    comPort.BaudRate = int.Parse(CMB_baudrate.Text);
                }
                catch
                {
                    CustomMessageBox.Show(Strings.InvalidBaudRate, Strings.ERROR);
                    return;
                }
                try
                {
                    comPort.Open();
                }
                catch (Exception ex)
                {
                    CustomMessageBox.Show(Strings.ErrorConnecting + "\n" + ex.ToString(), Strings.ERROR);
                    return;
                }


                string alt = "100";

                if (MainV2.comPort.MAV.cs.firmware == Firmwares.ArduCopter2)
                {
                    alt = (10*CurrentState.multiplierdist).ToString("0");
                }
                else
                {
                    alt = (100*CurrentState.multiplierdist).ToString("0");
                }
                if (DialogResult.Cancel == InputBox.Show("Enter Alt", "Enter Alt (relative to home alt)", ref alt))
                    return;

                intalt = (int) (100*CurrentState.multiplierdist);
                if (!int.TryParse(alt, out intalt))
                {
                    CustomMessageBox.Show(Strings.InvalidAlt, Strings.ERROR);
                    return;
                }

                intalt = (int) (intalt/CurrentState.multiplierdist);

                t12 = new System.Threading.Thread(new System.Threading.ThreadStart(mainloop))
                {
                    IsBackground = true,
                    Name = "followme Input"
                };
                t12.Start();

                BUT_connect.Text = Strings.Stop;
            }
        }

        void mainloop()
        {
            DateTime nextsend = DateTime.Now;

            StreamWriter sw = new StreamWriter(File.OpenWrite("followmeraw.txt"));

            threadrun = true;
            while (threadrun)
            {
                try
                {
                    string line = comPort.ReadLine();

                    sw.WriteLine(line);

                    //string line = string.Format("$GP{0},{1:HHmmss},{2},{3},{4},{5},{6},{7},{8},{9},{10},{11},{12},{13},", "GGA", DateTime.Now.ToUniversalTime(), Math.Abs(lat * 100), MainV2.comPort.MAV.cs.lat < 0 ? "S" : "N", Math.Abs(lng * 100), MainV2.comPort.MAV.cs.lng < 0 ? "W" : "E", MainV2.comPort.MAV.cs.gpsstatus, MainV2.comPort.MAV.cs.satcount, MainV2.comPort.MAV.cs.gpshdop, MainV2.comPort.MAV.cs.alt, "M", 0, "M", "");
                    if (line.StartsWith("$GPGGA") || line.StartsWith("$GNGGA")) // 
                    {
                        string[] items = line.Trim().Split(',', '*');

                        if (items[15] != GetChecksum(line.Trim()))
                        {
                            Console.WriteLine("Bad Nmea line " + items[15] + " vs " + GetChecksum(line.Trim()));
                            continue;
                        }

                        if (items[6] == "0")
                        {
                            Console.WriteLine("No Fix");
                            continue;
                        }

                        gotolocation.Lat = double.Parse(items[2], CultureInfo.InvariantCulture)/100.0;

                        gotolocation.Lat = (int) gotolocation.Lat + ((gotolocation.Lat - (int) gotolocation.Lat)/0.60);

                        if (items[3] == "S")
                            gotolocation.Lat *= -1;

                        gotolocation.Lng = double.Parse(items[4], CultureInfo.InvariantCulture)/100.0;

                        gotolocation.Lng = (int) gotolocation.Lng + ((gotolocation.Lng - (int) gotolocation.Lng)/0.60);

                        if (items[5] == "W")
                            gotolocation.Lng *= -1;

                        gotolocation.Alt = intalt;

                        gotolocation.Tag = "Sats " + items[7] + " hdop " + items[8];
                    }


                    if (DateTime.Now > nextsend && gotolocation.Lat != 0 && gotolocation.Lng != 0 &&
                        gotolocation.Alt != 0) // 200 * 10 = 2 sec /// lastgotolocation != gotolocation && 
                    {
                        nextsend = DateTime.Now.AddMilliseconds(1000/updaterate);
                        Console.WriteLine("Sending follow wp " + DateTime.Now.ToString("h:MM:ss") + " " +
                                          gotolocation.Lat + " " + gotolocation.Lng + " " + gotolocation.Alt);
                        lastgotolocation = new PointLatLngAlt(gotolocation);

                        Locationwp gotohere = new Locationwp();

                        gotohere.id = (ushort) MAVLink.MAV_CMD.WAYPOINT;
                        gotohere.alt = (float) (gotolocation.Alt);
                        gotohere.lat = (gotolocation.Lat);
                        gotohere.lng = (gotolocation.Lng);

                        try
                        {
                            updateLocationLabel(gotohere);
                        }
                        catch
                        {
                        }

                        if (MainV2.comPort.BaseStream.IsOpen && MainV2.comPort.giveComport == false)
                        {
                            try
                            {
                                MainV2.comPort.giveComport = true;

                                MainV2.comPort.setGuidedModeWP(gotohere, false);

                                MainV2.comPort.giveComport = false;
                            }
                            catch
                            {
                                MainV2.comPort.giveComport = false;
                            }
                        }
                    }
                }
                catch
                {
                    System.Threading.Thread.Sleep((int) (1000/updaterate));
                }
            }

            sw.Close();
        }

        private void updateLocationLabel(Locationwp plla)
        {
            if (!Instance.IsDisposed)
            {
                Instance.BeginInvoke(
                    (MethodInvoker)
                        delegate
                        {
                            Instance.LBL_location.Text = gotolocation.Lat + " " + gotolocation.Lng + " " +
                                                         gotolocation.Alt + " " + gotolocation.Tag;
                        }
                    );
            }
        }

        private void SerialOutput_FormClosing(object sender, FormClosingEventArgs e)
        {
        }

        // Calculates the checksum for a sentence
        string GetChecksum(string sentence)
        {
            // Loop through all chars to get a checksum
            int Checksum = 0;
            foreach (char Character in sentence.ToCharArray())
            {
                switch (Character)
                {
                    case '$':
                        // Ignore the dollar sign
                        break;
                    case '*':
                        // Stop processing before the asterisk
                        return Checksum.ToString("X2");
                    default:
                        // Is this the first value for the checksum?
                        if (Checksum == 0)
                        {
                            // Yes. Set the checksum to the value
                            Checksum = Convert.ToByte(Character);
                        }
                        else
                        {
                            // No. XOR the checksum with this character's value
                            Checksum = Checksum ^ Convert.ToByte(Character);
                        }
                        break;
                }
            }
            // Return the checksum formatted as a two-character hexadecimal
            return Checksum.ToString("X2");
        }

        private void CMB_updaterate_SelectedIndexChanged(object sender, EventArgs e)
        {
            try
            {
                updaterate = float.Parse(CMB_updaterate.Text.Replace("hz", ""));
            }
            catch
            {
                CustomMessageBox.Show(Strings.InvalidUpdateRate, Strings.ERROR);
            }
        }
    }
}