internal EyeTrackerCalibrator(EyeTrackerDevice device, IEyeTrackerDriver tracker)
{
_tracker = tracker;
State = CalibratorState.None;
Target = device;
DeviceInfo = device.DeviceInfo;
HeadPositioning = new HeadPositioning(tracker);
Calibrations = new ReadOnlyCollection <CalibrationResult>(_calibrations);
_states = CreateStateMachine();
}
public bool ConnectToDevice()
{
try
{
Log?.Invoke(this, new Core.LogMessage(Core.LogLevel.Info, LogTags.Connection, "Searching for an eye tracker..."));
using (CancellationTokenSource cts = new CancellationTokenSource(TimeSpan.FromSeconds(10)))
{
var tracker = _browser.SearchAsync(cts.Token)
.ConfigureAwait(false)
.GetAwaiter()
.GetResult();
if (tracker != null)
{
string name = tracker.Name ?? String.Empty;
string productId = tracker.ProductId ?? String.Empty;
string familyName = tracker.FamilyName ?? String.Empty;
Log?.Invoke(this, new Core.LogMessage(Core.LogLevel.Info, LogTags.Connection, $"Eye tracker found: {familyName} - {name} ({productId}). Connecting..."));
AttachEventHandlers(tracker);
tracker.Connect();
DeviceInfo.Name = name;
DeviceInfo.FamilyName = familyName;
DeviceInfo.ProductId = productId;
_connectedTracker = tracker;
Log?.Invoke(this, new Core.LogMessage(Core.LogLevel.Info, LogTags.Connection, "Connection successful"));
OnCanCalibrateChanged();
return(true);
}
}
Log?.Invoke(this, new Core.LogMessage(Core.LogLevel.Error, LogTags.Connection, "No eye tracker found."));
}
catch (OperationCanceledException)
{
Log?.Invoke(this, new Core.LogMessage(Core.LogLevel.Error, LogTags.Connection, "Failed to find an eye tracker within the time limit."));
}
catch (Exception ex)
{
Log?.Invoke(this, new Core.LogMessage(Core.LogLevel.Error, LogTags.Connection, "Failed to connect to an eye tracker.", ex));
ConnectionError?.Invoke(this, new ConnectionException("Failed to connect to an eye tracker, see inner exception for details.", ex));
}
return(false);
}
private void tracker_GazeDataReceived(IEyeTrackerDriver sender, GazeData gaze)
{
double?distance = gaze.GetEyeDistance();
double?relativeEyeDistance = gaze.GetRelativeEyeDistance();
var recommendation = GetRecommendation(relativeEyeDistance);
// Point (0,0,0) of the TrackBox Coordinate System is in the top right corner nearest to the eye tracker from the user's
// point of view (see Figure 3, Tobii Analytics SDK Developers Guide, p. 15), not the top left corner like the screen is,
// so we swap the X coordinate. Y coordinate is still in the right direction.
var leftEyePosition = new Point2(1 - gaze.LeftEye.EyePosition3DRelative.X, gaze.LeftEye.EyePosition3DRelative.Y);
var rightEyePosition = new Point2(1 - gaze.RightEye.EyePosition3DRelative.X, gaze.RightEye.EyePosition3DRelative.Y);
PositionChanged?.Invoke(this, new EyesPosition(leftEyePosition, gaze.Validity.HasLeftEye(),
rightEyePosition, gaze.Validity.HasRightEye(),
distance, relativeEyeDistance, recommendation));
}
internal HeadPositioning(IEyeTrackerDriver tracker)
{
_tracker = tracker;
}
void Tracker_GazeDataReceived(IEyeTrackerDriver sender, GazeData data)
{
Data?.Invoke(this, data);
}
private void DetachEventHandlers(IEyeTrackerDriver tracker)
{
tracker.ConnectionError -= Tracker_ConnectionError;
tracker.TrackBoxChanged -= Tracker_TrackBoxChanged;
tracker.DisplayAreaChanged -= Tracker_DisplayAreaChanged;
}
