Added MGRS coordinate conversion methods

src/Geo/QGCGeo.cc

@@ -8,23 +8,19 @@
  ****************************************************************************/
 
 #include <QDebug>
+#include <QString>
 
 #include <cmath>
 #include <limits>
 
 #include "QGCGeo.h"
 #include "UTMUPS.hpp"
+#include "MGRS.hpp"
 
 // These defines are private
 #define M_DEG_TO_RAD (M_PI / 180.0)
-
 #define M_RAD_TO_DEG (180.0 / M_PI)
-
-#define CONSTANTS_ONE_G					9.80665f		/* m/s^2		*/
-#define CONSTANTS_AIR_DENSITY_SEA_LEVEL_15C		1.225f			/* kg/m^3		*/
-#define CONSTANTS_AIR_GAS_CONST				287.1f 			/* J/(kg * K)		*/
-#define CONSTANTS_ABSOLUTE_NULL_CELSIUS			-273.15f		/* °C			*/
-#define CONSTANTS_RADIUS_OF_EARTH			6371000			/* meters (m)		*/
+#define CONSTANTS_RADIUS_OF_EARTH 6371000 // meters (m)
 
 static const double epsilon = std::numeric_limits<double>::epsilon();
 
@@ -90,17 +86,63 @@ void convertNedToGeo(double x, double y, double z, QGeoCoordinate origin, QGeoCo
 }
 
 int convertGeoToUTM(const QGeoCoordinate& coord, double& easting, double& northing)
+{
+    try {
+        int zone;
+        bool northp;
+        GeographicLib::UTMUPS::Forward(coord.latitude(), coord.longitude(), zone, northp, easting, northing);
+        return zone;
+    } catch(...) {
+        return 0;
+    }
+}
+
+bool convertUTMToGeo(double easting, double northing, int zone, bool southhemi, QGeoCoordinate& coord)
+{
+    double lat, lon;
+    try {
+        GeographicLib::UTMUPS::Reverse(zone, !southhemi, easting, northing, lat, lon);
+    } catch(...) {
+        return false;
+    }
+    coord.setLatitude(lat);
+    coord.setLongitude(lon);
+
+    return true;
+}
+
+QString convertGeoToMGRS(const QGeoCoordinate& coord)
 {
     int zone;
     bool northp;
-    GeographicLib::UTMUPS::Forward(coord.latitude(), coord.longitude(), zone, northp, easting, northing);
-    return zone;
+    double x, y;
+    std::string mgrs;
+
+    try {
+        GeographicLib::UTMUPS::Forward(coord.latitude(), coord.longitude(), zone, northp, x, y);
+        GeographicLib::MGRS::Forward(zone, northp, x, y, coord.latitude(), 5, mgrs);
+    } catch(...) {
+        mgrs = "";
+    }
+
+    return QString::fromStdString(mgrs);
 }
 
-void convertUTMToGeo(double easting, double northing, int zone, bool southhemi, QGeoCoordinate& coord)
+bool convertMGRSToGeo(QString mgrs, QGeoCoordinate& coord)
 {
+    int zone, prec;
+    bool northp;
+    double x, y;
     double lat, lon;
-    GeographicLib::UTMUPS::Reverse(zone, !southhemi, easting, northing, lat, lon);
+
+    try {
+        GeographicLib::MGRS::Reverse(mgrs.simplified().replace(" ", "").toStdString(), zone, northp, x, y, prec);
+        GeographicLib::UTMUPS::Reverse(zone, northp, x, y, lat, lon);
+    } catch(...) {
+        return false;
+    }
     coord.setLatitude(lat);
     coord.setLongitude(lon);
+
+    return true;
 }

src/Geo/QGCGeo.h

@@ -58,6 +58,7 @@ void convertNedToGeo(double x, double y, double z, QGeoCoordinate origin, QGeoCo
 //
 // Returns:
 //   The UTM zone used for calculating the values of x and y.
+//   If conversion failed the function returns 0
 int convertGeoToUTM(const QGeoCoordinate& coord, double& easting, double& northing);
 
 // UTMXYToLatLon
@@ -78,7 +79,30 @@ int convertGeoToUTM(const QGeoCoordinate& coord, double& easting, double& northi
 // lon - The longitude of the point, in radians.
 //
 // Returns:
-// The function does not return a value.
-void convertUTMToGeo(double easting, double northing, int zone, bool southhemi, QGeoCoordinate& coord);
+// The function returns true if conversion succeeded.
+bool convertUTMToGeo(double easting, double northing, int zone, bool southhemi, QGeoCoordinate& coord);
+
+// Converts a latitude/longitude pair to MGRS string
+//
+// Inputs:
+//   coord - Latitude, Longiture coordinate
+//
+// Returns:
+//   The MGRS coordinate string
+//   If conversion fails the function returns empty string
+QString convertGeoToMGRS(const QGeoCoordinate& coord);
+
+// Converts MGRS string to a latitude/longitude pair.
+//
+// Inputs:
+// mgrs - MGRS coordinate string
+//
+// Outputs:
+// lat - The latitude of the point, in radians.
+// lon - The longitude of the point, in radians.
+//
+// Returns:
+// The function returns true if conversion succeeded.
+bool convertMGRSToGeo(QString mgrs, QGeoCoordinate& coord);
 
 #endif // QGCGEO_H

src/SHPFileHelper.cc

@@ -142,9 +142,7 @@ bool SHPFileHelper::loadPolygonFromFile(const QString& shpFile, QList<QGeoCoordi
 
     for (int i=0; i<shpObject->nVertices; i++) {
         QGeoCoordinate coord;
-        if (utmZone) {
-            convertUTMToGeo(shpObject->padfX[i], shpObject->padfY[i], utmZone, utmSouthernHemisphere, coord);
-        } else {
+        if (!utmZone || !convertUTMToGeo(shpObject->padfX[i], shpObject->padfY[i], utmZone, utmSouthernHemisphere, coord)) {
             coord.setLatitude(shpObject->padfY[i]);
             coord.setLongitude(shpObject->padfX[i]);
         }