/// <summary>
/// Enter the calibration validation mode and starts subscribing to gaze data from the eye tracker.
/// </summary>
public void EnterValidationMode()
{
if (State != ValidationState.NotInValidationMode)
{
throw new InvalidOperationException("Validation mode already entered");
}
_dataMap = new List <KeyValuePair <NormalizedPoint2D, Queue <GazeDataEventArgs> > >();
_result.UpdateResult(new List <CalibrationValidationPoint>(), float.NaN, float.NaN, float.NaN, float.NaN, float.NaN, float.NaN);
State = ValidationState.NotCollectingData;
_eyeTracker.GazeDataReceived += OnGazeDataReceived;
}
public CalibrationValidationResult Compute()
{
if (IsCollectingData)
{
throw new InvalidOperationException("Compute called while collecting data");
}
var points = new List <CalibrationValidationPoint>();
foreach (var kv in _dataMap)
{
var targetPoint2D = kv.Key;
var samples = kv.Value;
var targetPoint3D = targetPoint2D.NormalizedPoint2DToPoint3D(_eyeTracker.GetDisplayArea());
if (samples.Count < _sampleCount)
{
// We timed out before collecting enough valid samples.
// Set the timeout flag and continue.
points.Add(new CalibrationValidationPoint(targetPoint2D, -1, -1, -1, -1, -1, -1, true, samples.ToArray()));
continue;
}
var gazePointAverageLeft = samples.Average(s => s.LeftEye.GazePoint.PositionInUserCoordinates);
var gazePointAverageRight = samples.Average(s => s.RightEye.GazePoint.PositionInUserCoordinates);
var gazeOriginAverageLeft = samples.Average(s => s.LeftEye.GazeOrigin.PositionInUserCoordinates);
var gazeOriginAverageRight = samples.Average(s => s.RightEye.GazeOrigin.PositionInUserCoordinates);
var directionGazePointLeft = gazeOriginAverageLeft.NormalizedDirection(gazePointAverageLeft);
var directionTargetLeft = gazeOriginAverageLeft.NormalizedDirection(targetPoint3D);
var accuracyLeftEye = directionTargetLeft.Angle(directionGazePointLeft);
var directionGazePointRight = gazeOriginAverageRight.NormalizedDirection(gazePointAverageRight);
var directionTargetRight = gazeOriginAverageRight.NormalizedDirection(targetPoint3D);
var accuracyRightEye = directionTargetRight.Angle(directionGazePointRight);
var varianceLeft = samples.Select(s => Math.Pow(s
.LeftEye.GazeOrigin.PositionInUserCoordinates.NormalizedDirection(s.LeftEye.GazePoint.PositionInUserCoordinates)
.Angle(s.LeftEye.GazeOrigin.PositionInUserCoordinates.NormalizedDirection(gazePointAverageLeft)), 2)).Average();
var varianceRight = samples.Select(s => Math.Pow(s
.RightEye.GazeOrigin.PositionInUserCoordinates.NormalizedDirection(s.RightEye.GazePoint.PositionInUserCoordinates)
.Angle(s.RightEye.GazeOrigin.PositionInUserCoordinates.NormalizedDirection(gazePointAverageRight)), 2)).Average();
var precisionLeftEye = varianceLeft > 0 ? Math.Sqrt(varianceLeft) : 0;
var precisionRightEye = varianceRight > 0 ? Math.Sqrt(varianceRight) : 0;
var precisionLeftEyeRMS = samples.RootMeanSquare(s => s.LeftEye);
var precisionRightEyeRMS = samples.RootMeanSquare(s => s.RightEye);
points.Add(new CalibrationValidationPoint(
targetPoint2D,
(float)accuracyLeftEye,
(float)precisionLeftEye,
(float)accuracyRightEye,
(float)precisionRightEye,
(float)precisionLeftEyeRMS,
(float)precisionRightEyeRMS,
false,
samples.ToArray()));
}
if (points.Count == 0)
{
_latestResult.UpdateResult(points, 0, 0, 0);
}
else
{
var validPoints = points.Where(p => !p.TimedOut);
if (validPoints.Count() == 0)
{
_latestResult.UpdateResult(points, 0, 0, 0);
}
else
{
var avaragePrecisionLeftEye = validPoints.Select(p => p.PrecisionLeftEye).Average();
var avaragePrecisionRightEye = validPoints.Select(p => p.PrecisionRightEye).Average();
var avarageAccuracyLeftEye = validPoints.Select(p => p.AccuracyLeftEye).Average();
var avarageAccuracyRightEye = validPoints.Select(p => p.AccuracyRightEye).Average();
var averagePrecisionLeftEyeRMS = validPoints.Select(p => p.PrecisionLeftEyeRMS).Average();
var averagePrecisionRightEyeRMS = validPoints.Select(p => p.PrecisionRightEyeRMS).Average();
_latestResult.UpdateResult(
points,
(avarageAccuracyLeftEye + avarageAccuracyRightEye) / 2.0f,
(avaragePrecisionLeftEye + avaragePrecisionRightEye) / 2.0f,
(averagePrecisionLeftEyeRMS + averagePrecisionRightEyeRMS) / 2.0f);
}
}
return(_latestResult);
}