Structural changes to handle edge cases better when starting and stop…

…ping tracking

StartTracker now returns bool indicating success. Only does anything meaningful in SmartEye right now.

Similarly, CalibrationResult now has an IsValid method.

Main window should now respond gracefully to a tracker failing to start (when implemented)

itrace_core/CalibrationResult.cs

@@ -19,11 +19,16 @@ namespace iTrace_Core
     abstract class CalibrationResult
     {
         public abstract void WriteToXMLWriter(XmlTextWriter xmlTextWriter);
+        public abstract bool IsValid();
     }
 
     class EmptyCalibrationResult : CalibrationResult
     {
         public override void WriteToXMLWriter(XmlTextWriter xmlTextWriter) { }
+        public override bool IsValid() //TODO
+        {
+            throw new System.NotImplementedException();
+        }
     }
 
     class TobiiCalibrationResult : CalibrationResult
@@ -41,6 +46,11 @@ public TobiiCalibrationResult(Tobii.Research.CalibrationResult calibrationResult
             SessionManager.GetInstance().GenerateCalibrationTimeStamp();
         }
 
+        public override bool IsValid() //TODO
+        {
+            throw new System.NotImplementedException();
+        }
+
         public List<Point> GetLeftEyePoints()
         {
             List<Point> leftEyePoints = new List<Point>();
@@ -133,6 +143,11 @@ public GazePointCalibrationResult(string xmlCalibrationData, int numberOfPoints)
             SessionManager.GetInstance().GenerateCalibrationTimeStamp();
         }
 
+        public override bool IsValid() //TODO
+        {
+            throw new System.NotImplementedException();
+        }
+
         public override void WriteToXMLWriter(XmlTextWriter xmlTextWriter)
         {
             XmlNode recNode = XmlDoc.FirstChild;
@@ -185,6 +200,11 @@ public SmartEyeCalibrationResult(SEWorldModel worldModel, List<SETarget> calibra
             SessionManager.GetInstance().GenerateCalibrationTimeStamp();
         }
 
+        public override bool IsValid() //TODO
+        {
+            return screenMapping.IsValid() && calibrationTargets.Count > 0;
+        }
+
         public override void WriteToXMLWriter(XmlTextWriter xmlTextWriter)
         {
             worldModel.WriteToXMLWriter(xmlTextWriter);

itrace_core/GazePointTracker.cs

@@ -82,7 +82,7 @@ public String GetTrackerSerialNumber()
             return TrackerSerialNumber;
         }
 
-        public void StartTracker()
+        public bool StartTracker()
         {
             new System.Threading.Thread(() =>
             {
@@ -92,6 +92,8 @@ public void StartTracker()
             Console.WriteLine("START GP TRACKING");
             Writer.Write("<SET ID=\"ENABLE_SEND_DATA\" STATE=\"1\" />\r\n");
             Writer.Flush();
+
+            return true;
         }
 
         public void StopTracker()

itrace_core/ITracker.cs

@@ -17,7 +17,7 @@ interface ITracker
     {
         void EnterCalibration();
         void LeaveCalibration();
-        void StartTracker();
+        bool StartTracker();
         void StopTracker();
         String GetTrackerName();
         String GetTrackerSerialNumber();

itrace_core/MainWindow.xaml.cs

@@ -291,6 +291,16 @@ private void StartTracker(object sender, RoutedEventArgs e)
             }
             else
             {
+                bool trackerStarted = TrackerManager.StartTracker();
+
+                if (!trackerStarted)
+                {
+                    //Fail to start
+                    Console.WriteLine("Failed to start tracker: " + TrackerManager.GetActiveTracker().GetTrackerName());
+                    return;
+                }
+
+                //Maybe figure out something less janky for this AL
                 string trackerID = TrackerManager.GetActiveTracker().GetTrackerName() + TrackerManager.GetActiveTracker().GetTrackerSerialNumber();
                 if (trackerID != SessionManager.GetInstance().CalibratedTrackerID)
                     SessionManager.GetInstance().ClearCalibration();
@@ -313,7 +323,6 @@ private void StartTracker(object sender, RoutedEventArgs e)
 
                 ActivateTrackerButton.Content = Properties.Resources.StopTracking;
 
-                TrackerManager.StartTracker();
                 ActivateCalibrationButton.IsEnabled = false;
                 ShowEyeStatusButton.IsEnabled = false;
                 TrackerList.IsEnabled = false;

itrace_core/MouseTracker.cs

@@ -42,9 +42,10 @@ public String GetTrackerSerialNumber()
             return "";
         }
 
-        public void StartTracker()
+        public bool StartTracker()
         {
             MouseLocationTick.Start();
+            return true;
         }
 
         public void StopTracker()

itrace_core/ScreenMapping.cs

@@ -44,11 +44,13 @@ public ScreenMapping(SEWorldScreen[] seScreens, Screen[] osScreens)
                     mapping = rule.GetMapping();
                     break;
                 }
-
-            if (mapping.Count == 0)
-                throw new ArgumentException("No reasonable mapping between world model screens and device screens!");
         }
 
+        //Check that world model maps any screens
+        public bool IsValid()
+        {
+            return mapping.Count > 0;
+        }
 
         /// <summary>
         /// Get the screen whose name matches the name of the provided seScreenName, presumably obtained from an intersection

itrace_core/SmartEyeTracker.cs

@@ -16,7 +16,6 @@
 using iTrace_Core.Properties;
 using Newtonsoft.Json.Linq;
 using System.Collections.Generic;
-using System.Numerics;
 using System.Windows.Forms;
 
 namespace iTrace_Core
@@ -88,8 +87,6 @@ public SmartEyeTracker()
                 double accLeft = accuracy.Value<JToken>(0).Value<double>();
                 double accRight = accuracy.Value<JToken>(1).Value<double>();
 
-                //Get world and calibration points
-                GetWorldCalibration();
             }
             catch (Exception e)
             {
@@ -180,39 +177,56 @@ public void CleanupConnections()
         //Retrieve the World Model and calibration error vectors. Returns true on success
         private Boolean GetWorldCalibration()
         {
-            //Retrieve WorldModel
+            List<SETarget> targets = new List<SETarget>();
+            String WorldModelString;
 
-            SendRpc(new SERPC("getWorldModel").GetNetstring());
-            JToken result = ReceiveRpcResponse().GetValue("result");
+            try
+            {
+                //Retrieve WorldModel
+                SendRpc(new SERPC("getWorldModel").GetNetstring());
+                JToken result = ReceiveRpcResponse().GetValue("result");
 
-            //Escaped String representing the world model
-            String WorldModelString = result.Value<String>("worldModel");
+                //Escaped String representing the world model
+                WorldModelString = result.Value<String>("worldModel");
 
-            List<SETarget> targets = new List<SETarget>();
+                //Retrieve calibration targets
+                int targetNumber = 0;
+                while (true)
+                {
+                    //Retrieve a target
+                    SendRpc(new SERPCGetTargetStats(targetNumber++).GetNetstring());
+                    SETarget target = ReceiveRpcResponse().GetValue("result").ToObject<SETarget>();
 
-            //Retrieve calibration targets
-            int targetNumber = 0;
-            while (true)
-            {
-                SendRpc(new SERPCGetTargetStats(targetNumber++).GetNetstring());
-                SETarget target = ReceiveRpcResponse().GetValue("result").ToObject<SETarget>();
+                    //Ran out of targets
+                    if (!target.TargetValid())
+                        break;
 
-                if (!target.TargetValid())
-                    break;
+                    targets.Add(target);
+                }
 
-                targets.Add(target);
-            }
+                if (targets.Count == 0)
+                {
+                    //No targets, most likely user has not done a gaze calibration in SmartEye
+                    System.Windows.Forms.MessageBox.Show("SmartEye returned no calibration points. Perform a calibration from the SmartEye program before proceeding. \n\nMake sure that the correct World Model is selected before calibrating, or you will have to do it again!");
+                    return false;
+                }
 
-            if (targets.Count == 0)
+            } catch (Exception e)
             {
-                //No targets, most likely user has not done a gaze calibration in SmartEye
-                System.Windows.Forms.MessageBox.Show("SmartEye is connected, but reported no calibration point data. Perform a gaze calibration from the SmartEye software.");
-                return false;
+                throw new Exception("Failed to retrieve SmartEye WorldModel and calibration points");   
             }
 
             //Store world model string and calibration data
+            //TODO exception handling for invalid worldModelString
             SEWorldModel worldModel = new SEWorldModel(WorldModelString);
+
             seCalibrationResult = new SmartEyeCalibrationResult(worldModel, targets);
+
+            if (!seCalibrationResult.IsValid())
+            {
+                System.Windows.Forms.MessageBox.Show("The SmartEye World Model does not match the displays present on this computer. Make sure the correct world model is selected and perform another SmartEye calibration.");
+            }
+
             SessionManager.GetInstance().SetCalibration(seCalibrationResult, this);
 
             return true;
@@ -227,6 +241,7 @@ public JObject ReceiveRpcResponse()
             return JsonConvert.DeserializeObject<dynamic>(response);
         }
 
+        //An Rpc connection and UDP (Realtime) socket are required to track
         public bool TrackerFound()
         {
             return (RealtimeClient != null) && (RpcClient != null);
@@ -250,28 +265,48 @@ public void SendRpc(String netstring)
             RpcClient.GetStream().Write(buf, 0, buf.Length);
         }
 
-        public void StartTracker()
+        public bool StartTracker()
         {
+            //Before tracking starts the worldmodel must be valid and contain a set of calibration points
+            //Get world and calibration points
+            if (!GetWorldCalibration())
+                    return false;
+
+            //Tell SmartEye to start tracking (same as clicking track eye button)
             SendRpc(new SERPC("startTracking").GetNetstring());
+            ReceiveRpcResponse(); // Dummy receive to eat any error
+
+            //Used to stop listening thread loops
+            Listen = true;
 
+            //Realtime (UDP) thread
             new System.Threading.Thread(() =>
             {
                 System.Threading.Thread.CurrentThread.IsBackground = true;
                 ListenForData();
             }).Start();
 
+            //Latent (TCP) thread
             new System.Threading.Thread(() =>
             {
                 System.Threading.Thread.CurrentThread.IsBackground = true;
                 ListenForLatent();
             }).Start();
 
+            //Ok
             Console.WriteLine("START SE TRACKING");
+            return true;
         }
 
+        //Important to make sure the tracker is actually running before sending this, otherwise an error will be returned
         public void StopTracker()
         {
-            SendRpc(new SERPC("stopTracking").GetNetstring());
+            //Send stop command to SmartEye
+            if (Listen)
+            {
+                SendRpc(new SERPC("stopTracking").GetNetstring());
+                ReceiveRpcResponse(); // Dummy receive to eat any error
+            }
 
             Listen = false;
         }
@@ -301,8 +336,6 @@ private void TrackerInit()
 
         private void ListenForData()
         {
-            Listen = true;
-
             while (Listen)
             {
                 //Receive UDP packet

itrace_core/SocketServer.cs

@@ -104,6 +104,7 @@ private void ListenForConnections()
         {
             TcpClient client;
 
+            //For some reason this now doesn't stop when you close the main window, I think it did before. AL
             while (true)
             {
                 client = server.AcceptTcpClient();

itrace_core/TobiiTracker.cs

@@ -50,9 +50,10 @@ public String GetTrackerSerialNumber()
             return TrackingDevice.SerialNumber;
         }
 
-        public void StartTracker()
+        public bool StartTracker()
         {
             TrackingDevice.GazeDataReceived += ReceiveRawGaze;
+            return true;
         }
 
         public void StopTracker()

itrace_core/TrackerManager.cs

@@ -109,9 +109,11 @@ public Boolean Running()
 
         public Boolean StartTracker()
         {
-            Tracking = true;
+
             GazeHandler.Instance.StartHandler();
-            ActiveTracker.StartTracker();
+            if (ActiveTracker.StartTracker())
+                Tracking = true;
+
             return Tracking;
         }