Support for detailed Geo and UTM position editing

qgroundcontrol.pro

@@ -487,8 +487,9 @@ DebugBuild { PX4FirmwarePlugin { PX4FirmwarePluginFactory  { APMFirmwarePlugin {
 
 HEADERS += \
     src/AnalyzeView/ExifParser.h \
-    src/AnalyzeView/ULogParser.h \
+    src/AnalyzeView/LogDownloadController.h \
     src/AnalyzeView/PX4LogParser.h \
+    src/AnalyzeView/ULogParser.h \
     src/Audio/AudioOutput.h \
     src/Camera/QGCCameraControl.h \
     src/Camera/QGCCameraIO.h \
@@ -553,6 +554,7 @@ HEADERS += \
     src/QGCToolbox.h \
     src/QmlControls/AppMessages.h \
     src/QmlControls/CoordinateVector.h \
+    src/QmlControls/EditPositionDialogController.h \
     src/QmlControls/MavlinkQmlSingleton.h \
     src/QmlControls/ParameterEditorController.h \
     src/QmlControls/QGCFileDialogController.h \
@@ -586,7 +588,7 @@ HEADERS += \
     src/uas/UAS.h \
     src/uas/UASInterface.h \
     src/uas/UASMessageHandler.h \
-    src/AnalyzeView/LogDownloadController.h \
+    src/UTM.h \
 
 AndroidBuild {
 HEADERS += \
@@ -679,8 +681,9 @@ AndroidBuild {
 
 SOURCES += \
     src/AnalyzeView/ExifParser.cc \
-    src/AnalyzeView/ULogParser.cc \
+    src/AnalyzeView/LogDownloadController.cc \
     src/AnalyzeView/PX4LogParser.cc \
+    src/AnalyzeView/ULogParser.cc \
     src/Audio/AudioOutput.cc \
     src/Camera/QGCCameraControl.cc \
     src/Camera/QGCCameraIO.cc \
@@ -741,6 +744,7 @@ SOURCES += \
     src/QGCToolbox.cc \
     src/QmlControls/AppMessages.cc \
     src/QmlControls/CoordinateVector.cc \
+    src/QmlControls/EditPositionDialogController.cc \
     src/QmlControls/ParameterEditorController.cc \
     src/QmlControls/QGCFileDialogController.cc \
     src/QmlControls/QGCImageProvider.cc \
@@ -772,7 +776,7 @@ SOURCES += \
     src/main.cc \
     src/uas/UAS.cc \
     src/uas/UASMessageHandler.cc \
-    src/AnalyzeView/LogDownloadController.cc \
+    src/UTM.cpp \
 
 DebugBuild {
 SOURCES += \

qgroundcontrol.qrc

@@ -48,6 +48,7 @@
         <file alias="QGroundControl/Controls/CameraSection.qml">src/PlanView/CameraSection.qml</file>
         <file alias="QGroundControl/Controls/ClickableColor.qml">src/QmlControls/ClickableColor.qml</file>
         <file alias="QGroundControl/Controls/DropButton.qml">src/QmlControls/DropButton.qml</file>
+		<file alias="QGroundControl/Controls/EditPositionDialog.qml">src/QmlControls/EditPositionDialog.qml</file>
         <file alias="QGroundControl/Controls/ExclusiveGroupItem.qml">src/QmlControls/ExclusiveGroupItem.qml</file>
         <file alias="QGroundControl/Controls/FactSliderPanel.qml">src/QmlControls/FactSliderPanel.qml</file>
 		<file alias="QGroundControl/Controls/FileButton.qml">src/QmlControls/FileButton.qml</file>
@@ -211,6 +212,7 @@
 		<file alias="CameraSpec.FactMetaData.json">src/MissionManager/CameraSpec.FactMetaData.json</file>
         <file alias="SpeedSection.FactMetaData.json">src/MissionManager/SpeedSection.FactMetaData.json</file>
         <file alias="MissionSettings.FactMetaData.json">src/MissionManager/MissionSettings.FactMetaData.json</file>
+		<file alias="EditPositionDialog.FactMetaData.json">src/QmlControls/EditPositionDialog.FactMetaData.json</file>
         <file alias="Vehicle/VehicleFact.json">src/Vehicle/VehicleFact.json</file>
         <file alias="Vehicle/BatteryFact.json">src/Vehicle/BatteryFact.json</file>
         <file alias="Vehicle/GPSFact.json">src/Vehicle/GPSFact.json</file>

src/MissionManager/QGCMapPolygonVisuals.qml

@@ -11,6 +11,7 @@ import QtQuick          2.3
 import QtQuick.Controls 1.2
 import QtLocation       5.3
 import QtPositioning    5.3
+import QtQuick.Dialogs  1.2
 
 import QGroundControl               1.0
 import QGroundControl.ScreenTools   1.0
@@ -378,6 +379,15 @@ Item {
         }
     }
 
+    Component {
+        id: editPositionDialog
+
+        EditPositionDialog {
+            coordinate: mapPolygon.center
+            onCoordinateChanged: mapPolygon.center = coordinate
+        }
+    }
+
     Component {
         id: centerDragAreaComponent
 
@@ -412,6 +422,12 @@ Item {
                     onTriggered:    radiusDialog.visible = true
                 }
 
+                MenuItem {
+                    text:           qsTr("Edit position..." )
+                    enabled:        _circle
+                    onTriggered:    qgcView.showDialog(editPositionDialog, qsTr("Edit Position"), qgcView.showDialogDefaultWidth, StandardButton.Cancel)
+                }
+
                 MenuItem {
                     text:           qsTr("Load KML...")
                     onTriggered:    kmlLoadDialog.openForLoad()

src/PlanView/MissionItemEditor.qml

@@ -62,6 +62,15 @@ Rectangle {
         }
     }
 
+    Component {
+        id: editPositionDialog
+
+        EditPositionDialog {
+            coordinate: missionItem.coordinate
+            onCoordinateChanged: missionItem.coordinate = coordinate
+        }
+    }
+
     QGCLabel {
         id:                     label
         anchors.verticalCenter: commandPicker.verticalCenter
@@ -136,6 +145,12 @@ Rectangle {
                 visible:        !_waypointsOnlyMode
             }
 
+            MenuItem {
+                text:           qsTr("Edit position...")
+                visible:        missionItem.specifiesCoordinate
+                onTriggered:    qgcView.showDialog(editPositionDialog, qsTr("Edit Position"), qgcView.showDialogDefaultWidth, StandardButton.Cancel)
+            }
+
             MenuSeparator {
                 visible: missionItem.isSimpleItem && !_waypointsOnlyMode
             }

src/QGCApplication.cc

@@ -83,6 +83,7 @@
 #include "QGCCameraManager.h"
 #include "CameraCalc.h"
 #include "VisualMissionItem.h"
+#include "EditPositionDialogController.h"
 
 #ifndef NO_SERIAL_LINK
 #include "SerialLink.h"
@@ -379,6 +380,7 @@ void QGCApplication::_initCommon(void)
     qmlRegisterType<JoystickConfigController>       ("QGroundControl.Controllers", 1, 0, "JoystickConfigController");
     qmlRegisterType<LogDownloadController>          ("QGroundControl.Controllers", 1, 0, "LogDownloadController");
     qmlRegisterType<SyslinkComponentController>     ("QGroundControl.Controllers", 1, 0, "SyslinkComponentController");
+    qmlRegisterType<EditPositionDialogController>   ("QGroundControl.Controllers", 1, 0, "EditPositionDialogController");
 #ifndef __mobile__
     qmlRegisterType<ViewWidgetController>           ("QGroundControl.Controllers", 1, 0, "ViewWidgetController");
     qmlRegisterType<CustomCommandWidgetController>  ("QGroundControl.Controllers", 1, 0, "CustomCommandWidgetController");

src/QGCGeo.cc

@@ -7,11 +7,13 @@
  *
  ****************************************************************************/
 
+#include <QDebug>
 
 #include <cmath>
 #include <limits>
 
 #include "QGCGeo.h"
+#include "UTM.h"
 
 // These defines are private
 #define M_DEG_TO_RAD (M_PI / 180.0)
@@ -81,3 +83,16 @@ void convertNedToGeo(double x, double y, double z, QGeoCoordinate origin, QGeoCo
     coord->setAltitude(-z + origin.altitude());
 }
 
+int convertGeoToUTM(const QGeoCoordinate& coord, double& easting, double& northing)
+{
+    return LatLonToUTMXY(coord.latitude(), coord.longitude(), -1 /* zone */, easting, northing);
+}
+
+void convertUTMToGeo(double easting, double northing, int zone, bool southhemi, QGeoCoordinate& coord)
+{
+    double latRadians, lonRadians;
+
+    UTMXYToLatLon (easting, northing, zone, southhemi, latRadians, lonRadians);
+    coord.setLatitude(RadToDeg(latRadians));
+    coord.setLongitude(RadToDeg(lonRadians));
+}

src/QGCGeo.h

@@ -41,4 +41,44 @@ void convertGeoToNed(QGeoCoordinate coord, QGeoCoordinate origin, double* x, dou
  */
 void convertNedToGeo(double x, double y, double z, QGeoCoordinate origin, QGeoCoordinate *coord);
 
+// LatLonToUTMXY
+// Converts a latitude/longitude pair to x and y coordinates in the
+// Universal Transverse Mercator projection.
+//
+// Inputs:
+//   lat - Latitude of the point, in radians.
+//   lon - Longitude of the point, in radians.
+//   zone - UTM zone to be used for calculating values for x and y.
+//          If zone is less than 1 or greater than 60, the routine
+//          will determine the appropriate zone from the value of lon.
+//
+// Outputs:
+//   x - The x coordinate (easting) of the computed point. (in meters)
+//   y - The y coordinate (northing) of the computed point. (in meters)
+//
+// Returns:
+//   The UTM zone used for calculating the values of x and y.
+int convertGeoToUTM(const QGeoCoordinate& coord, double& easting, double& northing);
+
+// UTMXYToLatLon
+//
+// Converts x and y coordinates in the Universal Transverse Mercator//   The UTM zone parameter should be in the range [1,60].
+
+// projection to a latitude/longitude pair.
+//
+// Inputs:
+// x - The easting of the point, in meters.
+// y - The northing of the point, in meters.
+// zone - The UTM zone in which the point lies.
+// southhemi - True if the point is in the southern hemisphere;
+//               false otherwise.
+//
+// Outputs:
+// lat - The latitude of the point, in radians.
+// 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);
+
 #endif // QGCGEO_H

src/QmlControls/EditPositionDialog.FactMetaData.json

+[
+{
+    "name":             "Latitude",
+    "shortDescription": "Latitude of item position",
+    "type":             "double",
+    "min":              -90.0,
+    "max":              90.0,
+    "decimalPlaces":    7
+},
+{
+    "name":             "Longitude",
+    "shortDescription": "Longitude of item position",
+    "type":             "double",
+    "min":              -180.0,
+    "max":              180.0,
+    "decimalPlaces":    7
+},
+{
+    "name":             "Easting",
+    "shortDescription": "Easting of item position",
+    "type":             "double",
+    "decimalPlaces":    7
+},
+{
+    "name":             "Northing",
+    "shortDescription": "Northing of item position",
+    "type":             "double",
+    "decimalPlaces":    7
+},
+{
+    "name":             "Zone",
+    "shortDescription": "UTM zone",
+    "type":             "uint8",
+    "min":              1,
+    "max":              60
+},
+{
+    "name":             "Hemisphere",
+    "shortDescription": "Hemisphere for position",
+    "type":             "uint8",
+    "enumStrings":      "North,South",
+    "enumValues":       "0,1"
+}
+]

src/QmlControls/EditPositionDialog.qml

+/****************************************************************************
+ *
+ *   (c) 2009-2016 QGROUNDCONTROL PROJECT <http://www.qgroundcontrol.org>
+ *
+ * QGroundControl is licensed according to the terms in the file
+ * COPYING.md in the root of the source code directory.
+ *
+ ****************************************************************************/
+
+import QtQuick          2.3
+import QtQuick.Controls 1.2
+import QtQuick.Layouts  1.2
+
+import QGroundControl               1.0
+import QGroundControl.Palette       1.0
+import QGroundControl.Controls      1.0
+import QGroundControl.FactControls  1.0
+import QGroundControl.ScreenTools   1.0
+import QGroundControl.Controllers   1.0
+
+QGCViewDialog {
+    property alias coordinate: controller.coordinate
+
+    property real   _margin:        ScreenTools.defaultFontPixelWidth / 2
+    property real   _fieldWidth:    ScreenTools.defaultFontPixelWidth * 10.5
+
+    EditPositionDialogController {
+        id: controller
+
+        Component.onCompleted: initValues()
+    }
+
+    QGCFlickable {
+        anchors.fill:   parent
+        contentHeight:  column.height
+
+        Column {
+            id:             column
+            anchors.left:   parent.left
+            anchors.right:  parent.right
+            spacing:        ScreenTools.defaultFontPixelHeight
+
+            GridLayout {
+                anchors.left:   parent.left
+                anchors.right:  parent.right
+                columnSpacing:  _margin
+                rowSpacing:     _margin
+                columns:        2
+
+                QGCLabel { text: qsTr("Latitude") }
+                FactTextField {
+                    fact:               controller.latitude
+                    Layout.fillWidth:   true
+                }
+
+                QGCLabel { text: qsTr("Longitude") }
+                FactTextField {
+                    fact:               controller.longitude
+                    Layout.fillWidth:   true
+                }
+            }
+
+            QGCButton {
+                anchors.right:  parent.right
+                text:           qsTr("Set Geographic")
+
+                onClicked: {
+                    controller.setFromGeo()
+                    reject()
+                }
+            }
+
+            GridLayout {
+                anchors.left:   parent.left
+                anchors.right:  parent.right
+                columnSpacing:  _margin
+                rowSpacing:     _margin
+                columns:        2
+
+                QGCLabel { text: qsTr("Zone") }
+                FactTextField {
+                    fact:               controller.zone
+                    Layout.fillWidth:   true
+                }
+
+                QGCLabel { text: qsTr("Hemisphere") }
+                FactComboBox {
+                    fact:               controller.hemisphere
+                    indexModel:         false
+                    Layout.fillWidth:   true
+                }
+
+                QGCLabel { text: qsTr("Easting") }
+                FactTextField {
+                    fact:               controller.easting
+                    Layout.fillWidth:   true
+                }
+
+                QGCLabel { text: qsTr("Northing") }
+                FactTextField {
+                    fact:               controller.northing
+                    Layout.fillWidth:   true
+                }
+            }
+
+            QGCButton {
+                anchors.right:  parent.right
+                text:           qsTr("Set UTM")
+
+                onClicked: {
+                    controller.setFromUTM()
+                    reject()
+                }
+            }
+        } // Column
+    } // QGCFlickable
+} // QGCViewDialog

src/QmlControls/EditPositionDialogController.cc

+/****************************************************************************
+ *
+ *   (c) 2009-2016 QGROUNDCONTROL PROJECT <http://www.qgroundcontrol.org>
+ *
+ * QGroundControl is licensed according to the terms in the file
+ * COPYING.md in the root of the source code directory.
+ *
+ ****************************************************************************/
+
+#include "EditPositionDialogController.h"
+#include "QGCGeo.h"
+
+const char*  EditPositionDialogController::_latitudeFactName =      "Latitude";
+const char*  EditPositionDialogController::_longitudeFactName =     "Longitude";
+const char*  EditPositionDialogController::_zoneFactName =          "Zone";
+const char*  EditPositionDialogController::_hemisphereFactName =    "Hemisphere";
+const char*  EditPositionDialogController::_eastingFactName =       "Easting";
+const char*  EditPositionDialogController::_northingFactName =      "Northing";
+
+QMap<QString, FactMetaData*> EditPositionDialogController::_metaDataMap;
+
+EditPositionDialogController::EditPositionDialogController(void)
+    : _latitudeFact     (0, _latitudeFactName,      FactMetaData::valueTypeDouble)
+    , _longitudeFact    (0, _longitudeFactName,     FactMetaData::valueTypeDouble)
+    , _zoneFact         (0, _zoneFactName,          FactMetaData::valueTypeUint8)
+    , _hemisphereFact   (0, _hemisphereFactName,    FactMetaData::valueTypeUint8)
+    , _eastingFact      (0, _eastingFactName,       FactMetaData::valueTypeDouble)
+    , _northingFact     (0, _northingFactName,      FactMetaData::valueTypeDouble)
+{
+    if (_metaDataMap.isEmpty()) {
+        _metaDataMap = FactMetaData::createMapFromJsonFile(QStringLiteral(":/json/EditPositionDialog.FactMetaData.json"), NULL /* QObject parent */);
+    }
+
+    _latitudeFact.setMetaData   (_metaDataMap[_latitudeFactName]);
+    _longitudeFact.setMetaData  (_metaDataMap[_longitudeFactName]);
+    _zoneFact.setMetaData       (_metaDataMap[_zoneFactName]);
+    _hemisphereFact.setMetaData (_metaDataMap[_hemisphereFactName]);
+    _eastingFact.setMetaData    (_metaDataMap[_eastingFactName]);
+    _northingFact.setMetaData   (_metaDataMap[_northingFactName]);
+}
+
+void EditPositionDialogController::setCoordinate(QGeoCoordinate coordinate)
+{
+    if (coordinate != _coordinate) {
+        _coordinate = coordinate;
+        emit coordinateChanged(coordinate);
+    }
+}
+
+void EditPositionDialogController::initValues(void)
+{
+    _latitudeFact.setRawValue(_coordinate.latitude());
+    _longitudeFact.setRawValue(_coordinate.longitude());
+
+    double easting, northing;
+    int zone = convertGeoToUTM(_coordinate, easting, northing);
+    _zoneFact.setRawValue(zone);
+    _hemisphereFact.setRawValue(_coordinate.latitude() < 0);
+    _eastingFact.setRawValue(easting);
+    _northingFact.setRawValue(northing);
+}
+
+void EditPositionDialogController::setFromGeo(void)
+{
+    _coordinate.setLatitude(_latitudeFact.rawValue().toDouble());
+    _coordinate.setLongitude(_longitudeFact.rawValue().toDouble());
+    emit coordinateChanged(_coordinate);
+}
+
+void EditPositionDialogController::setFromUTM(void)
+{
+    qDebug() << _eastingFact.rawValue().toDouble() << _northingFact.rawValue().toDouble() << _zoneFact.rawValue().toInt() << (_hemisphereFact.rawValue().toInt() == 1);
+    convertUTMToGeo(_eastingFact.rawValue().toDouble(), _northingFact.rawValue().toDouble(), _zoneFact.rawValue().toInt(), _hemisphereFact.rawValue().toInt() == 1, _coordinate);
+    qDebug() << _eastingFact.rawValue().toDouble() << _northingFact.rawValue().toDouble() << _zoneFact.rawValue().toInt() << (_hemisphereFact.rawValue().toInt() == 1) << _coordinate;
+    emit coordinateChanged(_coordinate);
+}

src/QmlControls/EditPositionDialogController.h

+/****************************************************************************
+ *
+ *   (c) 2009-2016 QGROUNDCONTROL PROJECT <http://www.qgroundcontrol.org>
+ *
+ * QGroundControl is licensed according to the terms in the file
+ * COPYING.md in the root of the source code directory.
+ *
+ ****************************************************************************/
+
+#pragma once
+
+#include <QObject>
+#include <QGeoCoordinate>
+
+#include "FactSystem.h"
+
+class EditPositionDialogController : public QObject
+{
+    Q_OBJECT
+    
+public:
+    EditPositionDialogController(void);
+    
+    Q_PROPERTY(QGeoCoordinate   coordinate  READ coordinate WRITE setCoordinate NOTIFY coordinateChanged)
+    Q_PROPERTY(Fact*            latitude    READ latitude                       CONSTANT)
+    Q_PROPERTY(Fact*            longitude   READ longitude                      CONSTANT)
+    Q_PROPERTY(Fact*            zone        READ zone                           CONSTANT)
+    Q_PROPERTY(Fact*            hemisphere  READ hemisphere                     CONSTANT)
+    Q_PROPERTY(Fact*            easting     READ easting                        CONSTANT)
+    Q_PROPERTY(Fact*            northing    READ northing                       CONSTANT)
+
+    QGeoCoordinate  coordinate(void) const { return _coordinate; }
+    Fact* latitude  (void) { return &_latitudeFact; }
+    Fact* longitude (void) { return &_longitudeFact; }
+    Fact* zone      (void) { return &_zoneFact; }
+    Fact* hemisphere(void) { return &_hemisphereFact; }
+    Fact* easting   (void) { return &_eastingFact; }
+    Fact* northing  (void) { return &_northingFact; }
+
+    void setCoordinate(QGeoCoordinate coordinate);
+
+    Q_INVOKABLE void initValues(void);
+    Q_INVOKABLE void setFromGeo(void);
+    Q_INVOKABLE void setFromUTM(void);
+
+signals:
+    void coordinateChanged(QGeoCoordinate coordinate);
+
+private:
+    static QMap<QString, FactMetaData*> _metaDataMap;
+
+    QGeoCoordinate _coordinate;
+
+    Fact _latitudeFact;
+    Fact _longitudeFact;
+    Fact _zoneFact;
+    Fact _hemisphereFact;
+    Fact _eastingFact;
+    Fact _northingFact;
+
+    static const char*  _latitudeFactName;
+    static const char*  _longitudeFactName;
+    static const char*  _zoneFactName;
+    static const char*  _hemisphereFactName;
+    static const char*  _eastingFactName;
+    static const char*  _northingFactName;
+};

src/QmlControls/QGroundControl.Controls.qmldir

@@ -7,6 +7,7 @@ CameraSection           1.0 CameraSection.qml
 ClickableColor          1.0 ClickableColor.qml
 DropButton              1.0 DropButton.qml
 DropPanel               1.0 DropPanel.qml
+EditPositionDialog      1.0 EditPositionDialog.qml
 ExclusiveGroupItem      1.0 ExclusiveGroupItem.qml
 FactSliderPanel         1.0 FactSliderPanel.qml
 FileButton              1.0 FileButton.qml

src/UTM.h

+// UTM.h
+
+// Original Javascript by Chuck Taylor
+// Port to C++ by Alex Hajnal
+//
+// *** THIS CODE USES 32-BIT FLOATS BY DEFAULT ***
+// *** For 64-bit double-precision edit this file: undefine FLOAT_32 and define FLOAT_64 (see below)
+// 
+// This is a simple port of the code on the Geographic/UTM Coordinate Converter (1) page from Javascript to C++.
+// Using this you can easily convert between UTM and WGS84 (latitude and longitude).
+// Accuracy seems to be around 50cm (I suspect rounding errors are limiting precision).
+// This code is provided as-is and has been minimally tested; enjoy but use at your own risk!
+// The license for UTM.cpp and UTM.h is the same as the original Javascript: 
+// "The C++ source code in UTM.cpp and UTM.h may be copied and reused without restriction."
+// 
+// 1) http://home.hiwaay.net/~taylorc/toolbox/geography/geoutm.html
+
+#ifndef UTM_H
+#define UTM_H
+
+// Choose floating point precision:
+
+// 32-bit (for Teensy 3.5/3.6 ARM boards, etc.)
+#define FLOAT_64
+
+// 64-bit (for desktop/server use)
+//#define FLOAT_64
+
+#ifdef FLOAT_64
+#define FLOAT double
+#define SIN sin
+#define COS cos
+#define TAN tan
+#define POW pow
+#define SQRT sqrt
+#define FLOOR floor
+
+#else
+#ifdef FLOAT_32
+#define FLOAT float
+#define SIN sinf
+#define COS cosf
+#define TAN tanf
+#define POW powf
+#define SQRT sqrtf
+#define FLOOR floorf
+
+#endif
+#endif
+
+
+#include <math.h>
+
+#define pi 3.14159265358979
+
+/* Ellipsoid model constants (actual values here are for WGS84) */
+#define sm_a 6378137.0
+#define sm_b 6356752.314
+#define sm_EccSquared 6.69437999013e-03
+
+#define UTMScaleFactor 0.9996
+
+// DegToRad
+// Converts degrees to radians.
+FLOAT DegToRad(FLOAT deg);
+
+// RadToDeg
+// Converts radians to degrees.
+FLOAT RadToDeg(FLOAT rad);
+
+// ArcLengthOfMeridian
+// Computes the ellipsoidal distance from the equator to a point at a
+// given latitude.
+// 
+// Reference: Hoffmann-Wellenhof, B., Lichtenegger, H., and Collins, J.,
+// GPS: Theory and Practice, 3rd ed.  New York: Springer-Verlag Wien, 1994.
+// 
+// Inputs:
+//     phi - Latitude of the point, in radians.
+// 
+// Globals:
+//     sm_a - Ellipsoid model major axis.
+//     sm_b - Ellipsoid model minor axis.
+// 
+// Returns:
+//     The ellipsoidal distance of the point from the equator, in meters.
+FLOAT ArcLengthOfMeridian (FLOAT phi);
+
+// UTMCentralMeridian
+// Determines the central meridian for the given UTM zone.
+//
+// Inputs:
+//     zone - An integer value designating the UTM zone, range [1,60].
+//
+// Returns:
+//   The central meridian for the given UTM zone, in radians
+//   Range of the central meridian is the radian equivalent of [-177,+177].
+FLOAT UTMCentralMeridian(int zone);
+
+// FootpointLatitude
+//
+// Computes the footpoint latitude for use in converting transverse
+// Mercator coordinates to ellipsoidal coordinates.
+//
+// Reference: Hoffmann-Wellenhof, B., Lichtenegger, H., and Collins, J.,
+//   GPS: Theory and Practice, 3rd ed.  New York: Springer-Verlag Wien, 1994.
+//
+// Inputs:
+//   y - The UTM northing coordinate, in meters.
+//
+// Returns:
+//   The footpoint latitude, in radians.
+FLOAT FootpointLatitude(FLOAT y);
+
+// MapLatLonToXY
+// Converts a latitude/longitude pair to x and y coordinates in the
+// Transverse Mercator projection.  Note that Transverse Mercator is not
+// the same as UTM; a scale factor is required to convert between them.
+//
+// Reference: Hoffmann-Wellenhof, B., Lichtenegger, H., and Collins, J.,
+// GPS: Theory and Practice, 3rd ed.  New York: Springer-Verlag Wien, 1994.
+//
+// Inputs:
+//    phi - Latitude of the point, in radians.
+//    lambda - Longitude of the point, in radians.
+//    lambda0 - Longitude of the central meridian to be used, in radians.
+//
+// Outputs:
+//    x - The x coordinate of the computed point.
+//    y - The y coordinate of the computed point.
+//
+// Returns:
+//    The function does not return a value.
+void MapLatLonToXY (FLOAT phi, FLOAT lambda, FLOAT lambda0, FLOAT &x, FLOAT &y);
+
+// MapXYToLatLon
+// Converts x and y coordinates in the Transverse Mercator projection to
+// a latitude/longitude pair.  Note that Transverse Mercator is not
+// the same as UTM; a scale factor is required to convert between them.
+//
+// Reference: Hoffmann-Wellenhof, B., Lichtenegger, H., and Collins, J.,
+//   GPS: Theory and Practice, 3rd ed.  New York: Springer-Verlag Wien, 1994.
+//
+// Inputs:
+//   x - The easting of the point, in meters.
+//   y - The northing of the point, in meters.
+//   lambda0 - Longitude of the central meridian to be used, in radians.
+//
+// Outputs:
+//   phi    - Latitude in radians.
+//   lambda - Longitude in radians.
+//
+// Returns:
+//   The function does not return a value.
+//
+// Remarks:
+//   The local variables Nf, nuf2, tf, and tf2 serve the same purpose as
+//   N, nu2, t, and t2 in MapLatLonToXY, but they are computed with respect
+//   to the footpoint latitude phif.
+//
+//   x1frac, x2frac, x2poly, x3poly, etc. are to enhance readability and
+//   to optimize computations.
+void MapXYToLatLon (FLOAT x, FLOAT y, FLOAT lambda0, FLOAT& phi, FLOAT& lambda);
+
+// LatLonToUTMXY
+// Converts a latitude/longitude pair to x and y coordinates in the
+// Universal Transverse Mercator projection.
+//
+// Inputs:
+//   lat - Latitude of the point, in radians.
+//   lon - Longitude of the point, in radians.
+//   zone - UTM zone to be used for calculating values for x and y.
+//          If zone is less than 1 or greater than 60, the routine
+//          will determine the appropriate zone from the value of lon.
+//
+// Outputs:
+//   x - The x coordinate (easting) of the computed point. (in meters)
+//   y - The y coordinate (northing) of the computed point. (in meters)
+//
+// Returns:
+//   The UTM zone used for calculating the values of x and y.
+int LatLonToUTMXY (FLOAT lat, FLOAT lon, int zone, FLOAT& x, FLOAT& y);
+
+// UTMXYToLatLon
+//
+// Converts x and y coordinates in the Universal Transverse Mercator//   The UTM zone parameter should be in the range [1,60].
+
+// projection to a latitude/longitude pair.
+//
+// Inputs:
+// x - The easting of the point, in meters.
+// y - The northing of the point, in meters.
+// zone - The UTM zone in which the point lies.
+// southhemi - True if the point is in the southern hemisphere;
+//               false otherwise.
+//
+// Outputs:
+// lat - The latitude of the point, in radians.
+// lon - The longitude of the point, in radians.
+// 
+// Returns:
+// The function does not return a value.
+void UTMXYToLatLon (FLOAT x, FLOAT y, int zone, bool southhemi, FLOAT& lat, FLOAT& lon);
+
+#endif
+