/// <summary> /// Reads the Heading direction /// </summary> /// <returns>The direction as an azimuth angle</returns> public Azimuth ReadHeading() { // Does it support the value we want? IHeadingSentence sentence = ReadTypedSentence() as IHeadingSentence; // If not, start over (recursive) while (sentence == null) { sentence = ReadTypedSentence() as IHeadingSentence; } // Return the location return(sentence.Heading); }
/// <summary> /// Translates the NmeaSentence /// </summary> /// <param name="sentence">The NMeaSentence to parse</param> public void Parse(NmeaSentence sentence) { /* NMEA data is parsed in a specific order to maximize data quality and also to reduce latency * problems. The date/time is processed first to minimize latency. Then, dilution of precision * values are processed. Finally, if precision is good enough to work with, remaining values are * processed. */ // Is this a fix method message? IFixMethodSentence fixMethodSentence = sentence as IFixMethodSentence; if (fixMethodSentence != null) { SetFixMethod(fixMethodSentence.FixMethod); } // Is this a fix quality message? IFixQualitySentence fixQualitySentence = sentence as IFixQualitySentence; if (fixQualitySentence != null) { SetFixQuality(fixQualitySentence.FixQuality); } #region Process common GPS information // If a fix is required, don't process time if (!IsFixRequired || (IsFixRequired && IsFixed)) { // Does this sentence support the UTC date and time? IUtcDateTimeSentence dateTimeSentence = sentence as IUtcDateTimeSentence; if (dateTimeSentence != null) { SetDateTimes(dateTimeSentence.UtcDateTime); } /* Some NMEA sentences provide UTC time information, but no date! To make this work, * we must combine the time report with the current UTC date. */ IUtcTimeSentence timeSentence = sentence as IUtcTimeSentence; if (timeSentence != null && !timeSentence.UtcTime.Equals(TimeSpan.MinValue) && !timeSentence.UtcTime.Equals(TimeSpan.Zero)) { SetDateTimes(new DateTime(DateTime.UtcNow.Year, DateTime.UtcNow.Month, DateTime.UtcNow.Day, timeSentence.UtcTime.Hours, timeSentence.UtcTime.Minutes, timeSentence.UtcTime.Seconds, timeSentence.UtcTime.Milliseconds, DateTimeKind.Utc)); } } // Does this sentence support horizontal DOP? IHorizontalDilutionOfPrecisionSentence hdopSentence = sentence as IHorizontalDilutionOfPrecisionSentence; if (hdopSentence != null) { SetHorizontalDilutionOfPrecision(hdopSentence.HorizontalDilutionOfPrecision); } // Does the sentence support vertical DOP? IVerticalDilutionOfPrecisionSentence vdopSentence = sentence as IVerticalDilutionOfPrecisionSentence; if (vdopSentence != null) { SetVerticalDilutionOfPrecision(vdopSentence.VerticalDilutionOfPrecision); } // Does the sentence support mean DOP? IPositionDilutionOfPrecisionSentence mdopSentence = sentence as IPositionDilutionOfPrecisionSentence; if (mdopSentence != null) { SetMeanDilutionOfPrecision(mdopSentence.PositionDilutionOfPrecision); } #endregion Process common GPS information // If a fix is required, don't process time if (!IsFixRequired || (IsFixRequired && IsFixed)) { // Is precision good enough to work with? if (HorizontalDilutionOfPrecision.Value <= MaximumHorizontalDilutionOfPrecision.Value) { #region Process real-time positional data // Does this sentence support lat/long info? IPositionSentence positionSentence = sentence as IPositionSentence; if (positionSentence != null) { SetPosition(positionSentence.Position); } // Does this sentence support bearing? IBearingSentence bearingSentence = sentence as IBearingSentence; if (bearingSentence != null) { SetBearing(bearingSentence.Bearing); } // Does this sentence support heading? IHeadingSentence headingSentence = sentence as IHeadingSentence; if (headingSentence != null) { SetHeading(headingSentence.Heading); } // Does this sentence support speed? ISpeedSentence speedSentence = sentence as ISpeedSentence; if (speedSentence != null) { SetSpeed(speedSentence.Speed); } #endregion Process real-time positional data } // Is the vertical DOP low enough to be worth processing? if (VerticalDilutionOfPrecision.Value <= MaximumVerticalDilutionOfPrecision.Value) { #region Process altitude data // Does this sentence support altitude? IAltitudeSentence altitudeSentence = sentence as IAltitudeSentence; if (altitudeSentence != null) { SetAltitude(altitudeSentence.Altitude); } // Does this sentence support altitude? IAltitudeAboveEllipsoidSentence altitudeAboveEllipsoidSentence = sentence as IAltitudeAboveEllipsoidSentence; if (altitudeAboveEllipsoidSentence != null) { SetAltitude(altitudeAboveEllipsoidSentence.AltitudeAboveEllipsoid); } // Does this sentence support geoidal separation? IGeoidalSeparationSentence geoidSeparationSentence = sentence as IGeoidalSeparationSentence; if (geoidSeparationSentence != null) { SetGeoidalSeparation(geoidSeparationSentence.GeoidalSeparation); } #endregion Process altitude data } } #region Lower-priority information // Is this a fix mode sentence? IFixModeSentence fixModeSentence = sentence as IFixModeSentence; if (fixModeSentence != null) { SetFixMode(fixModeSentence.FixMode); } // Does this sentence have fix status? IFixStatusSentence fixedSentence = sentence as IFixStatusSentence; if (fixedSentence != null) { SetFixStatus(fixedSentence.FixStatus); } // Does this sentence support magnetic variation? IMagneticVariationSentence magVarSentence = sentence as IMagneticVariationSentence; if (magVarSentence != null) { SetMagneticVariation(magVarSentence.MagneticVariation); } // Process satellite data ISatelliteCollectionSentence satelliteSentence = sentence as ISatelliteCollectionSentence; if (satelliteSentence != null) { /* GPS.NET 2.0 performed thorough comparison of satellites in order to update * an *existing* instance of Satellite objects. I think now that this was overkill. * For performance and limited memory use, satellites are just overwritten. */ AppendSatellites(satelliteSentence.Satellites); } // Fixed satellite count IFixedSatelliteCountSentence fixedCountSentence = sentence as IFixedSatelliteCountSentence; if (fixedCountSentence != null) { SetFixedSatelliteCount(fixedCountSentence.FixedSatelliteCount); } // Process fixed satellites IFixedSatellitesSentence fixedSatellitesSentence = sentence as IFixedSatellitesSentence; if (fixedSatellitesSentence != null) { SetFixedSatellites(fixedSatellitesSentence.FixedSatellites); } #endregion Lower-priority information }
/// <summary> /// Decode the NMEA data. /// </summary> /// <param name="nmeaStrings">String array containing NMEA sentences.</param> /// <returns>Gps Data.</returns> public static GpsData DecodeNmea(string[] nmeaStrings) { GpsData gpsData = new GpsData(); try { for (int x = 0; x < nmeaStrings.Length; x++) { // Parse all the nmea setences found NmeaSentence sentence = new NmeaSentence(nmeaStrings[x]); // Is this a GPRMC sentence? if (sentence.CommandWord.EndsWith("RMC", StringComparison.Ordinal)) { gpsData.GPRMC = new GprmcSentence(sentence.Sentence); } // Is this a GPHDT sentence? if (sentence.CommandWord.EndsWith("HDT", StringComparison.Ordinal)) { gpsData.GPHDT = new GphdtSentence(sentence.Sentence); } // Is this a GPVTG sentence? if (sentence.CommandWord.EndsWith("VTG", StringComparison.Ordinal)) { gpsData.GPVTG = new GpvtgSentence(sentence.Sentence); } // Is this a GPGGA sentence? if (sentence.CommandWord.EndsWith("GGA", StringComparison.Ordinal)) { gpsData.GPGGA = new GpggaSentence(sentence.Sentence); } // Does this sentence support lat/long info? IPositionSentence positionSentence = sentence as IPositionSentence; if (positionSentence != null) { gpsData.Position = positionSentence.Position; } // Does this sentence support bearing? IBearingSentence bearingSentence = sentence as IBearingSentence; if (bearingSentence != null) { gpsData.Bearing = bearingSentence.Bearing; } // Does this sentence support heading? IHeadingSentence headingSentence = sentence as IHeadingSentence; if (headingSentence != null) { gpsData.Heading = headingSentence.Heading; } // Does this sentence support speed? ISpeedSentence speedSentence = sentence as ISpeedSentence; if (speedSentence != null) { gpsData.Speed = speedSentence.Speed; } } } catch (Exception e) { Debug.WriteLine("Error decoding GPS data.", e); } return(gpsData); }