private void UpdateDeviation()
{
if (AnyStale(new IQuantityWithMetaData[] { Sog, Cog, Heading }))
{
return;
}
if (Sog < MINIMUM_SPEED_FOR_VALID_CALCULATIONS)
{
return;
}
_compassCorrection.AddSample(Heading.Value, Cog.Value);
_compassCorrectionPersister.Write(_compassCorrection);
CorrectedHeading = new QuantityWithMetadata <IMessageCompassValue>(_compassCorrection.CorrectHeading(Heading.Value));
if (PropertyChanged == null)
{
return;
}
PropertyChanged(this, new PropertyChangedEventArgs("MeanDeviation"));
PropertyChanged(this, new PropertyChangedEventArgs("SampleCount"));
PropertyChanged(this, new PropertyChangedEventArgs("CorrectedHeading"));
}
private void OnIncomingMessage(MessageBase message, DateTime messagetime)
{
// ReSharper disable once SwitchStatementMissingSomeCases
switch (message.Name)
{
case MessageName.RMC:
{
var rmc = (RMC)message;
if (rmc.SOG > MINIMUM_SPEED_FOR_VALID_CALCULATIONS)
{
Cog = rmc.TMG;
Cog.Source = SourceType.External;
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs("Cog"));
Sog = rmc.SOG;
Sog.Source = SourceType.External;
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs("Sog"));
OnUpdateCog();
}
}
break;
case MessageName.HDG:
{
var hdg = (HDG)message;
if (null != hdg.MagneticContext)
{
_magneticContext = hdg.MagneticContext;
}
}
break;
}
if (message is IHaveHeading)
{
Heading = new QuantityWithMetadata <IMessageCompassValue>(_magneticContext.Magnetic((message as IHaveHeading).Heading));
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs("Heading"));
}
if (message is IHasPosition)
{
QuantityWithMetadata <Coordinate> c = (Coordinate)(message as IHasPosition).Position;
c.Source = SourceType.External;
c.Updated = messagetime;
OnUpdatePosition(c);
}
UpdateLastMessageDictionary(message);
}
private void OnUpdatePosition(QuantityWithMetadata <Coordinate> coordinate)
{
if (null == Sog || Sog.Source != SourceType.External || Sog.IsStale)
{
// Try to calculate Sog from position data
if (null != _lastposition && !_lastposition.IsStale)
{
var angulardistance = ((Coordinate)coordinate).Distance(_lastposition);
var distance = Ball.EarthSurfaceApproximation.Distance(angulardistance).NauticalMiles();
if (distance >= _minimumDistanceForCalculations.NauticalMiles())
{
var elapsed = DateTime.UtcNow - _lastposition.Updated;
if (elapsed.HasValue && elapsed.Value >= _minimumElapsedtimeForCalculations)
{
Sog = distance / elapsed.Value.TotalHours;
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs("Sog"));
}
}
}
}
if (null == Cog || Cog.Source != SourceType.External || Cog.IsStale)
{
// Try to calculate Cog from position data
if (null != _lastposition && !_lastposition.IsStale)
{
var angulardistance = ((Coordinate)coordinate).Distance(_lastposition);
var distance = Ball.EarthSurfaceApproximation.Distance(angulardistance).NauticalMiles();
if (distance >= _minimumDistanceForCalculations.NauticalMiles())
{
if (null != Sog && Sog > MINIMUM_SPEED_FOR_VALID_CALCULATIONS)
{
var truecog = _lastposition.Value.InitialCourse(coordinate);
Cog = new TrueMessageCompassValue(truecog.Degrees);
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs("Cog"));
OnUpdateCog();
}
}
}
}
_lastposition = coordinate;
}