Fixes in rtcm mesg parsing

qgroundcontrol.pro

@@ -1072,6 +1072,7 @@ SOURCES += \
     src/GPS/Drivers/src/sbf.cpp \
     src/GPS/GPSManager.cc \
     src/GPS/GPSProvider.cc \
+    src/GPS/NmeaMessage.cc \
     src/Joystick/JoystickSDL.cc \
     src/RunGuard.cc \
 }

src/GPS/CMakeLists.txt

@@ -9,6 +9,7 @@ add_library(gps
 	Drivers/src/ubx.cpp
 	GPSManager.cc
 	GPSProvider.cc
+	NmeaMessage.cc
 	RTCM/RTCMMavlink.cc
 )
 

src/GPS/NmeaMessage.cc

@@ -0,0 +1,92 @@
+//
+// Created by zdanek on 13.11.24.
+//
+
+#include "NmeaMessage.h"
+
+#include <QDateTime>
+#include <QtCore>
+#include <cmath>
+
+NmeaMessage::NmeaMessage(QGeoCoordinate coordinate) {
+  _coordinate = coordinate;
+}
+
+QString NmeaMessage::getGGA() {
+
+  double lat = _coordinate.latitude();
+  double lng = _coordinate.longitude();
+  double alt = _coordinate.altitude();
+
+  //  qCDebug(NTRIPLog) << "lat : " << lat << " lon : " << lng << " alt : " << alt;
+
+  QString time = QDateTime::currentDateTimeUtc().toString("hhmmss.zzz");
+
+  if (lat != 0 || lng != 0) {
+    if (std::isnan(alt))
+      alt = 0.0;
+
+    int latDegrees = (int)qFabs(lat);
+    double latMinutes = (qFabs(lat) - latDegrees) * 60.0;
+
+    int lngDegrees = (int)qFabs(lng);
+    double lngMinutes = (qFabs(lng) - lngDegrees) * 60.0;
+
+    // Format latitude degrees and minutes with leading zeros
+    QString latDegreesStr = QString("%1").arg(latDegrees, 2, 10, QChar('0'));
+    QString latMinutesStr =
+        QString("%1").arg(latMinutes, 7, 'f', 4, QChar('0'));
+    QString latStr = latDegreesStr + latMinutesStr;
+
+    // Format longitude degrees and minutes with leading zeros
+    QString lngDegreesStr = QString("%1").arg(lngDegrees, 3, 10, QChar('0'));
+    QString lngMinutesStr =
+        QString("%1").arg(lngMinutes, 7, 'f', 4, QChar('0'));
+    QString lngStr = lngDegreesStr + lngMinutesStr;
+
+    QString line =
+        QString("$GPGGA,%1,%2,%3,%4,%5,%6,%7,%8,%9,%10,%11,%12,%13,%14")
+            .arg(time)                // %1 - UTC Time
+            .arg(latStr)              // %2 - Latitude in NMEA format
+            .arg(lat < 0 ? "S" : "N") // %3 - N/S Indicator
+            .arg(lngStr)              // %4 - Longitude in NMEA format
+            .arg(lng < 0 ? "W" : "E") // %5 - E/W Indicator
+            .arg("1")                 // %6 - Fix Quality
+            .arg("10")                // %7 - Number of Satellites
+            .arg("1.0") // %8 - Horizontal Dilution of Precision (HDOP)
+            .arg(QString::number(alt, 'f', 2)) // %9 - Altitude
+            .arg("M")                          // %10 - Altitude Units
+            .arg("0")                          // %11 - Geoidal Separation
+            .arg("M")                          // %12 - Geoidal Separation Units
+            .arg("0.0") // %13 - Age of Differential GPS Data
+            .arg("0");  // %14 - Differential Reference Station ID
+
+    // Calculate checksum and send message
+    QString checkSum = _getCheckSum(line);
+    QString nmeaMessage = line + "*" + checkSum + "\r\n";
+
+    return nmeaMessage;
+  }
+  return QString();
+}
+
+QString NmeaMessage::_getCheckSum(QString line) {
+//  qCDebug(NTRIPLog) << "Calculating checksum";
+  QByteArray temp_Byte = line.toUtf8();
+  const char* buf = temp_Byte.constData();
+
+  char character;
+  int checksum = 0;
+
+  // Start from index 1 to skip the '$' character
+  for(int i = 1; i < line.length(); i++) {
+    character = buf[i];
+    if(character == '*') {
+      break;
+    }
+    checksum ^= character;
+  }
+
+  // Ensure the checksum is a two-digit uppercase hexadecimal string
+  return QString("%1").arg(checksum, 2, 16, QChar('0')).toUpper();
+}

src/GPS/NmeaMessage.h

@@ -0,0 +1,20 @@
+//
+// Created by zdanek on 13.11.24.
+//
+
+#pragma once
+
+#include <QGeoCoordinate>
+#include <QString>
+
+class NmeaMessage {
+public:
+  NmeaMessage(QGeoCoordinate coordinate);
+  QString getGGA();
+
+private:
+  QString _getCheckSum(QString line);
+  QGeoCoordinate _coordinate;
+};
+
+