Add new FactGroup support

Plumb through initial object mode on Vehicle

qgroundcontrol.pro

@@ -673,6 +673,7 @@ INCLUDEPATH += \
 
 HEADERS += \
     src/FactSystem/Fact.h \
+    src/FactSystem/FactGroup.h \
     src/FactSystem/FactControls/FactPanelController.h \
     src/FactSystem/FactMetaData.h \
     src/FactSystem/FactSystem.h \
@@ -682,6 +683,7 @@ HEADERS += \
 
 SOURCES += \
     src/FactSystem/Fact.cc \
+    src/FactSystem/FactGroup.cc \
     src/FactSystem/FactControls/FactPanelController.cc \
     src/FactSystem/FactMetaData.cc \
     src/FactSystem/FactSystem.cc \

qgroundcontrol.qrc

@@ -148,5 +148,8 @@
         <file alias="PX4/MavCmdInfoCommon.json">src/FirmwarePlugin/PX4/MavCmdInfoCommon.json</file>
         <file alias="PX4/MavCmdInfoFixedWing.json">src/FirmwarePlugin/PX4/MavCmdInfoFixedWing.json</file>
         <file alias="PX4/MavCmdInfoMultiRotor.json">src/FirmwarePlugin/PX4/MavCmdInfoMultiRotor.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>
     </qresource>
 </RCC>

src/FactSystem/Fact.cc

@@ -35,6 +35,8 @@ Fact::Fact(QObject* parent)
     , _rawValue(0)
     , _type(FactMetaData::valueTypeInt32)
     , _metaData(NULL)
+    , _sendValueChangedSignals(true)
+    , _deferredValueChangeSignal(false)
 {    
     FactMetaData* metaData = new FactMetaData(_type, this);
     setMetaData(metaData);
@@ -47,6 +49,8 @@ Fact::Fact(int componentId, QString name, FactMetaData::ValueType_t type, QObjec
     , _rawValue(0)
     , _type(type)
     , _metaData(NULL)
+    , _sendValueChangedSignals(true)
+    , _deferredValueChangeSignal(false)
 {
     FactMetaData* metaData = new FactMetaData(_type, this);
     setMetaData(metaData);
@@ -60,11 +64,13 @@ Fact::Fact(const Fact& other, QObject* parent)
 
 const Fact& Fact::operator=(const Fact& other)
 {
-    _name           = other._name;
-    _componentId    = other._componentId;
-    _rawValue          = other._rawValue;
-    _type           = other._type;
-    
+    _name                       = other._name;
+    _componentId                = other._componentId;
+    _rawValue                   = other._rawValue;
+    _type                       = other._type;
+    _sendValueChangedSignals    = other._sendValueChangedSignals;
+    _deferredValueChangeSignal  = other._deferredValueChangeSignal;
+
     if (_metaData && other._metaData) {
         *_metaData = *other._metaData;
     } else {
@@ -82,7 +88,7 @@ void Fact::forceSetRawValue(const QVariant& value)
         
         if (_metaData->convertAndValidateRaw(value, true /* convertOnly */, typedValue, errorString)) {
             _rawValue.setValue(typedValue);
-            emit valueChanged(cookedValue());
+            _sendValueChangedSignal(cookedValue());
             emit _containerRawValueChanged(rawValue());
         }
     } else {
@@ -99,7 +105,7 @@ void Fact::setRawValue(const QVariant& value)
         if (_metaData->convertAndValidateRaw(value, true /* convertOnly */, typedValue, errorString)) {
             if (typedValue != _rawValue) {
                 _rawValue.setValue(typedValue);
-                emit valueChanged(cookedValue());
+                _sendValueChangedSignal(cookedValue());
                 emit _containerRawValueChanged(rawValue());
             }
         }
@@ -141,7 +147,7 @@ void Fact::setEnumIndex(int index)
 void Fact::_containerSetRawValue(const QVariant& value)
 {
     _rawValue = value;
-    emit valueChanged(cookedValue());
+    _sendValueChangedSignal(cookedValue());
     emit vehicleUpdated(_rawValue);
 }
 
@@ -492,3 +498,29 @@ bool Fact::rebootRequired(void) const
         return false;
     }
 }
+
+void Fact::setSendValueChangedSignals (bool sendValueChangedSignals)
+{
+    if (sendValueChangedSignals != _sendValueChangedSignals) {
+        _sendValueChangedSignals = sendValueChangedSignals;
+        emit sendValueChangedSignalsChanged(_sendValueChangedSignals);
+    }
+}
+
+void Fact::_sendValueChangedSignal(QVariant value)
+{
+    if (_sendValueChangedSignals) {
+        emit valueChanged(value);
+        _deferredValueChangeSignal = false;
+    } else {
+        _deferredValueChangeSignal = true;
+    }
+}
+
+void Fact::sendDeferredValueChangedSignal(void)
+{
+    if (_deferredValueChangeSignal) {
+        _deferredValueChangeSignal = false;
+        emit valueChanged(cookedValue());
+    }
+}

src/FactSystem/Fact.h

@@ -117,6 +117,15 @@ public:
     void setEnumIndex       (int index);
     void setEnumStringValue (const QString& value);
 
+    // The following methods allow you to defer sending of the valueChanged signals in order to implement
+    // rate limited signalling for ui performance. Used by FactGroup for example.
+
+    void setSendValueChangedSignals (bool sendValueChangedSignals);
+    bool sendValueChangedSignals (void) const { return _sendValueChangedSignals; }
+    bool deferredValueChangeSignal(void) const { return _deferredValueChangeSignal; }
+    void clearDeferredValueChangeSignal(void) { _deferredValueChangeSignal = false; }
+    void sendDeferredValueChangedSignal(void);
+
     // C++ methods
 
     /// Sets and sends new value to vehicle even if value is the same
@@ -129,12 +138,14 @@ public:
     
     /// Generally you should not change the name of a fact. But if you know what you are doing, you can.
     void _setName(const QString& name) { _name = name; }
+
     
 signals:
     void bitmaskStringsChanged(void);
     void bitmaskValuesChanged(void);
     void enumStringsChanged(void);
     void enumValuesChanged(void);
+    void sendValueChangedSignalsChanged(bool sendValueChangedSignals);
 
     /// QObject Property System signal for value property changes
     ///
@@ -151,12 +162,15 @@ signals:
     
 protected:
     QString _variantToString(const QVariant& variant) const;
+    void _sendValueChangedSignal(QVariant value);
 
     QString                     _name;
     int                         _componentId;
     QVariant                    _rawValue;
     FactMetaData::ValueType_t   _type;
     FactMetaData*               _metaData;
+    bool                        _sendValueChangedSignals;
+    bool                        _deferredValueChangeSignal;
 };
 
 #endif

src/FactSystem/FactGroup.cc

@@ -0,0 +1,217 @@
+/*=====================================================================
+ 
+ QGroundControl Open Source Ground Control Station
+ 
+ (c) 2009 - 2014 QGROUNDCONTROL PROJECT <http://www.qgroundcontrol.org>
+ 
+ This file is part of the QGROUNDCONTROL project
+ 
+ QGROUNDCONTROL is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+ 
+ QGROUNDCONTROL is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+ 
+ You should have received a copy of the GNU General Public License
+ along with QGROUNDCONTROL. If not, see <http://www.gnu.org/licenses/>.
+ 
+ ======================================================================*/
+
+#include "FactGroup.h"
+#include "JsonHelper.h"
+
+#include <QJsonDocument>
+#include <QJsonParseError>
+#include <QJsonArray>
+#include <QDebug>
+#include <QFile>
+
+QGC_LOGGING_CATEGORY(FactGroupLog, "FactGroupLog")
+
+const char* FactGroup::_decimalPlacesJsonKey =      "decimalPlaces";
+const char* FactGroup::_nameJsonKey =               "name";
+const char* FactGroup::_propertiesJsonKey =         "properties";
+const char* FactGroup::_versionJsonKey =            "version";
+const char* FactGroup::_typeJsonKey =               "type";
+const char* FactGroup::_shortDescriptionJsonKey =   "shortDescription";
+const char* FactGroup::_unitsJsonKey =              "units";
+
+FactGroup::FactGroup(int updateRateMsecs, const QString& metaDataFile, QObject* parent)
+    : QObject(parent)
+    , _updateRateMSecs(updateRateMsecs)
+{
+    if (_updateRateMSecs > 0) {
+        connect(&_updateTimer, &QTimer::timeout, this, &FactGroup::_updateAllValues);
+        _updateTimer.setSingleShot(false);
+        _updateTimer.start(_updateRateMSecs);
+    }
+
+    _loadMetaData(metaDataFile);
+}
+
+Fact* FactGroup::getFact(const QString& name)
+{
+    if (_nameToFactMap.contains(name)) {
+        return _nameToFactMap[name];
+    } else {
+        qWarning() << "Unknown Fact" << name;
+    }
+
+    return NULL;
+}
+
+FactGroup* FactGroup::getFactGroup(const QString& name)
+{
+    if (_nameToFactGroupMap.contains(name)) {
+        return _nameToFactGroupMap[name];
+    } else {
+        qWarning() << "Unknown FactGroup" << name;
+    }
+
+    // FIXME: Return bogus fact
+    return NULL;
+}
+
+void FactGroup::_addFact(Fact* fact, const QString& name)
+{
+    if (_nameToFactMap.contains(name)) {
+        qWarning() << "Duplicate Fact" << name;
+        return;
+    }
+
+    fact->setSendValueChangedSignals(_updateRateMSecs == 0);
+    if (_nameToFactMetaDataMap.contains(name)) {
+        fact->setMetaData(_nameToFactMetaDataMap[name]);
+    }
+    _nameToFactMap[name] = fact;
+}
+
+void FactGroup::_addFactGroup(FactGroup* factGroup, const QString& name)
+{
+    if (_nameToFactGroupMap.contains(name)) {
+        qWarning() << "Duplicate FactGroup" << name;
+        return;
+    }
+
+    _nameToFactGroupMap[name] = factGroup;
+}
+
+void FactGroup::_updateAllValues(void)
+{
+    foreach(Fact* fact, _nameToFactMap) {
+        fact->sendDeferredValueChangedSignal();
+    }
+}
+
+void FactGroup::_loadMetaData(const QString& jsonFilename)
+{
+    if (jsonFilename.isEmpty()) {
+        return;
+    }
+
+    qCDebug(FactGroupLog) << "Loading" << jsonFilename;
+
+    QFile jsonFile(jsonFilename);
+    if (!jsonFile.open(QIODevice::ReadOnly | QIODevice::Text)) {
+        qWarning() << "Unable to open file" << jsonFilename << jsonFile.errorString();
+        return;
+    }
+
+    QByteArray bytes = jsonFile.readAll();
+    jsonFile.close();
+    QJsonParseError jsonParseError;
+    QJsonDocument doc = QJsonDocument::fromJson(bytes, &jsonParseError);
+    if (jsonParseError.error != QJsonParseError::NoError) {
+        qWarning() <<  "Unable to open json document" << jsonFilename << jsonParseError.errorString();
+        return;
+    }
+
+    QJsonObject json = doc.object();
+
+    int version = json.value(_versionJsonKey).toInt();
+    if (version != 1) {
+        qWarning() << "Invalid version" << version;
+        return;
+    }
+
+    QJsonValue jsonValue = json.value(_propertiesJsonKey);
+    if (!jsonValue.isArray()) {
+        qWarning() << "properties object not array";
+        return;
+    }
+
+    QJsonArray jsonArray = jsonValue.toArray();
+    foreach(QJsonValue property, jsonArray) {
+        if (!property.isObject()) {
+            qWarning() << "properties object should contain only objects";
+            return;
+        }
+        QJsonObject jsonObject = property.toObject();
+
+        // Make sure we have the required keys
+        QString errorString;
+        QStringList requiredKeys;
+        requiredKeys << _nameJsonKey << _decimalPlacesJsonKey << _typeJsonKey << _shortDescriptionJsonKey;
+        if (!JsonHelper::validateRequiredKeys(jsonObject, requiredKeys, errorString)) {
+            qWarning() << errorString;
+            return;
+        }
+
+        // Validate key types
+
+        QStringList             keys;
+        QList<QJsonValue::Type> types;
+        keys << _nameJsonKey << _decimalPlacesJsonKey;
+        types << QJsonValue::String << QJsonValue::Double;
+        if (!JsonHelper::validateKeyTypes(jsonObject, keys, types, errorString)) {
+            qWarning() << errorString;
+            return;
+        }
+
+        QString name = jsonObject.value(_nameJsonKey).toString();
+        if (_nameToFactMetaDataMap.contains(name)) {
+            qWarning() << "Duplicate property name" << name;
+            continue;
+        }
+
+        bool unknownType;
+        FactMetaData::ValueType_t type = FactMetaData::stringToType(jsonObject.value(_typeJsonKey).toString(), unknownType);
+        if (unknownType) {
+            qWarning() << "Unknown type" << jsonObject.value(_typeJsonKey).toString();
+            return;
+        }
+
+        QStringList enumValues, enumStrings;
+        if (!JsonHelper::parseEnum(jsonObject, enumStrings, enumValues, errorString)) {
+            qWarning() << errorString;
+            return;
+        }
+
+        FactMetaData* metaData = new FactMetaData(type, this);
+
+        metaData->setDecimalPlaces(jsonObject.value(_decimalPlacesJsonKey).toInt());
+        metaData->setShortDescription(jsonObject.value(_shortDescriptionJsonKey).toString());
+        metaData->setRawUnits(jsonObject.value(_unitsJsonKey).toString());
+
+        for (int i=0; i<enumValues.count(); i++) {
+            QVariant    enumVariant;
+            QString     errorString;
+
+            if (metaData->convertAndValidateRaw(enumValues[i], false /* validate */, enumVariant, errorString)) {
+                metaData->addEnumInfo(enumStrings[i], enumVariant);
+            } else {
+                qWarning() << "Invalid enum value, name:" << metaData->name()
+                            << " type:" << metaData->type() << " value:" << enumValues[i]
+                            << " error:" << errorString;
+                delete metaData;
+                return;
+            }
+        }
+
+        _nameToFactMetaDataMap[name] = metaData;
+    }
+}

src/FactSystem/FactGroup.h

@@ -0,0 +1,83 @@
+/*=====================================================================
+ 
+ QGroundControl Open Source Ground Control Station
+ 
+ (c) 2009 - 2014 QGROUNDCONTROL PROJECT <http://www.qgroundcontrol.org>
+ 
+ This file is part of the QGROUNDCONTROL project
+ 
+ QGROUNDCONTROL is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+ 
+ QGROUNDCONTROL is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+ 
+ You should have received a copy of the GNU General Public License
+ along with QGROUNDCONTROL. If not, see <http://www.gnu.org/licenses/>.
+ 
+ ======================================================================*/
+
+#ifndef FactGroup_H
+#define FactGroup_H
+
+#include "Fact.h"
+#include "QGCLoggingCategory.h"
+
+#include <QStringList>
+#include <QMap>
+#include <QTimer>
+
+Q_DECLARE_LOGGING_CATEGORY(VehicleLog)
+
+/// Used to group Facts together into an object hierarachy.
+class FactGroup : public QObject
+{
+    Q_OBJECT
+    
+public:
+    FactGroup(int updateRateMsecs, const QString& metaDataFile, QObject* parent = NULL);
+
+    Q_PROPERTY(QStringList factNames        READ factNames      CONSTANT)
+    Q_PROPERTY(QStringList factGroupNames   READ factGroupNames CONSTANT)
+
+    /// @return Fact for specified name, NULL if not found
+    Q_INVOKABLE Fact* getFact(const QString& name);
+
+    /// @return FactGroup for specified name, NULL if not found
+    Q_INVOKABLE FactGroup* getFactGroup(const QString& name);
+
+    QStringList factNames(void) const { return _nameToFactMap.keys(); }
+    QStringList factGroupNames(void) const { return _nameToFactGroupMap.keys(); }
+    
+protected:
+    void _addFact(Fact* fact, const QString& name);
+    void _addFactGroup(FactGroup* factGroup, const QString& name);
+
+    int _updateRateMSecs;   ///< Update rate for Fact::valueChanged signals, 0: immediate update
+
+private slots:
+    void _updateAllValues(void);
+
+private:
+    void _loadMetaData(const QString& filename);
+
+    QMap<QString, Fact*>            _nameToFactMap;
+    QMap<QString, FactGroup*>       _nameToFactGroupMap;
+    QMap<QString, FactMetaData*>    _nameToFactMetaDataMap;
+
+    QTimer _updateTimer;
+
+    static const char*  _propertiesJsonKey;
+    static const char*  _nameJsonKey;
+    static const char*  _decimalPlacesJsonKey;
+    static const char*  _typeJsonKey;
+    static const char*  _versionJsonKey;
+    static const char*  _shortDescriptionJsonKey;
+    static const char*  _unitsJsonKey;
+};
+
+#endif

src/FactSystem/FactMetaData.cc

@@ -398,3 +398,39 @@ void FactMetaData::setRawUnits(const QString& rawUnits)
 
     _setBuiltInTranslator();
 }
+
+FactMetaData::ValueType_t FactMetaData::stringToType(const QString& typeString, bool& unknownType)
+{
+    QStringList         knownTypeStrings;
+    QList<ValueType_t>  knownTypes;
+
+    unknownType = false;
+
+    knownTypeStrings << QStringLiteral("Uint8")
+                        << QStringLiteral("Int8")
+                        << QStringLiteral("Uint16")
+                        << QStringLiteral("Int16")
+                        << QStringLiteral("Uint32")
+                        << QStringLiteral("Int32")
+                        << QStringLiteral("Float")
+                        << QStringLiteral("Double");
+
+    knownTypes << valueTypeUint8
+                << valueTypeInt8
+                << valueTypeUint16
+                << valueTypeInt16
+                << valueTypeUint32
+                << valueTypeInt32
+                << valueTypeFloat
+                << valueTypeDouble;
+
+    for (int i=0; i<knownTypeStrings.count(); i++) {
+        if (knownTypeStrings[i].compare(typeString, Qt::CaseInsensitive) == 0) {
+            return knownTypes[i];
+        }
+    }
+
+    unknownType = true;
+
+    return valueTypeDouble;
+}

src/FactSystem/FactMetaData.h

@@ -120,6 +120,8 @@ public:
 
     static const int defaultDecimalPlaces = 3;
 
+    static ValueType_t stringToType(const QString& typeString, bool& unknownType);
+
 private:
     QVariant _minForType(void) const;
     QVariant _maxForType(void) const;

src/FactSystem/FactSystem.cc

@@ -25,6 +25,7 @@
 ///     @author Don Gagne <don@thegagnes.com>
 
 #include "FactSystem.h"
+#include "FactGroup.h"
 #include "FactPanelController.h"
 
 #include <QtQml>
@@ -41,6 +42,7 @@ void FactSystem::setToolbox(QGCToolbox *toolbox)
 {
     QGCTool::setToolbox(toolbox);
 
-    qmlRegisterType<Fact>(_factSystemQmlUri, 1, 0, "Fact");
+    qmlRegisterType<Fact>               (_factSystemQmlUri, 1, 0, "Fact");
+    qmlRegisterType<Fact>               (_factSystemQmlUri, 1, 0, "FactGroup");
     qmlRegisterType<FactPanelController>(_factSystemQmlUri, 1, 0, "FactPanelController");
 }

src/FlightDisplay/FlightDisplayView.qml

@@ -36,6 +36,7 @@ import QGroundControl.Controls      1.0
 import QGroundControl.Palette       1.0
 import QGroundControl.Vehicle       1.0
 import QGroundControl.Controllers   1.0
+import QGroundControl.FactSystem    1.0
 
 /// Flight Display View
 Item {
@@ -55,7 +56,6 @@ Item {
     readonly property real _defaultAltitudeWGS84:       0
     readonly property real _defaultGroundSpeed:         0
     readonly property real _defaultAirSpeed:            0
-    readonly property real _defaultClimbRate:           0
 
     readonly property string _mapName:                  "FlightDisplayView"
     readonly property string _showMapBackgroundKey:     "/showMapBackground"
@@ -65,14 +65,15 @@ Item {
     property bool _mainIsMap:           QGroundControl.loadBoolGlobalSetting(_mainIsMapKey,  true)
     property bool _isPipVisible:        QGroundControl.loadBoolGlobalSetting(_PIPVisibleKey, true)
 
-    property real _roll:                _activeVehicle ? (isNaN(_activeVehicle.roll)    ? _defaultRoll    : _activeVehicle.roll)    : _defaultRoll
-    property real _pitch:               _activeVehicle ? (isNaN(_activeVehicle.pitch)   ? _defaultPitch   : _activeVehicle.pitch)   : _defaultPitch
-    property real _heading:             _activeVehicle ? (isNaN(_activeVehicle.heading) ? _defaultHeading : _activeVehicle.heading) : _defaultHeading
+    property real _roll:                _activeVehicle ? _activeVehicle.roll.value    : _defaultRoll
+    property real _pitch:               _activeVehicle ? _activeVehicle.pitch.value   : _defaultPitch
+    property real _heading:             _activeVehicle ? _activeVehicle.heading.value : _defaultHeading
 
-    property real _altitudeWGS84:       _activeVehicle ? _activeVehicle.altitudeWGS84 : _defaultAltitudeWGS84
-    property real _groundSpeed:         _activeVehicle ? _activeVehicle.groundSpeed   : _defaultGroundSpeed
-    property real _airSpeed:            _activeVehicle ? _activeVehicle.airSpeed      : _defaultAirSpeed
-    property real _climbRate:           _activeVehicle ? _activeVehicle.climbRate     : _defaultClimbRate
+
+    property Fact _emptyFact:           Fact { }
+    property Fact _groundSpeedFact:     _activeVehicle ? _activeVehicle.groundSpeed   : _emptyFact
+    property Fact _airSpeedFact:        _activeVehicle ? _activeVehicle.airSpeed      : _emptyFact
+    property Fact _altitudeWGS84Fact:   _activeVehicle ? _activeVehicle.altitudeWGS84 : _emptyFact
 
     property bool activeVehicleJoystickEnabled: _activeVehicle ? _activeVehicle.joystickEnabled : false
 

src/FlightDisplay/FlightDisplayViewWidgets.qml

@@ -39,7 +39,8 @@ Item {
 
     readonly property string _InstrumentVisibleKey: "IsInstrumentPanelVisible"
 
-    property bool _isInstrumentVisible: QGroundControl.loadBoolGlobalSetting(_InstrumentVisibleKey, true)
+    property bool   _isInstrumentVisible:   QGroundControl.loadBoolGlobalSetting(_InstrumentVisibleKey, true)
+    property var    _activeVehicle:         multiVehicleManager.activeVehicle
 
     QGCMapPalette { id: mapPal; lightColors: !isBackgroundDark }
 
@@ -101,9 +102,9 @@ Item {
         heading:                _heading
         rollAngle:              _roll
         pitchAngle:             _pitch
-        altitude:               _altitudeWGS84
-        groundSpeed:            _groundSpeed
-        airSpeed:               _airSpeed
+        altitudeFact:           _altitudeWGS84Fact
+        groundSpeedFact:        _groundSpeedFact
+        airSpeedFact:           _airSpeedFact
         isSatellite:            _mainIsMap ? _flightMap ? _flightMap.isSatelliteMap : true : true
         z:                      QGroundControl.zOrderWidgets
         onClicked: {
@@ -127,7 +128,7 @@ Item {
             spacing:            ScreenTools.defaultFontPixelSize * 0.33
             anchors.verticalCenter: parent.verticalCenter
             QGCLabel {
-                text:           "Altitude (m)"
+                text:           _altitudeWGS84Fact.shortDescription + "(" + _altitudeWGS84Fact.units + ")"
                 font.pixelSize: ScreenTools.defaultFontPixelSize * 0.75
                 width:          parent.width
                 height:         ScreenTools.defaultFontPixelSize * 0.75
@@ -135,7 +136,7 @@ Item {
                 horizontalAlignment: TextEdit.AlignHCenter
             }
             QGCLabel {
-                text:           _altitudeWGS84 < 10000 ? _altitudeWGS84.toFixed(1) : _altitudeWGS84.toFixed(0)
+                text:           _altitudeWGS84Fact.valueString
                 font.pixelSize: ScreenTools.defaultFontPixelSize * 1.5
                 font.weight:    Font.DemiBold
                 width:          parent.width
@@ -143,7 +144,7 @@ Item {
                 horizontalAlignment: TextEdit.AlignHCenter
             }
             QGCLabel {
-                text:           "Ground Speed (km/h)"
+                text:           _groundSpeedFact.shortDescription + "(" + _groundSpeedFact.units + ")"
                 font.pixelSize: ScreenTools.defaultFontPixelSize * 0.75
                 width:          parent.width
                 height:         ScreenTools.defaultFontPixelSize * 0.75
@@ -151,7 +152,7 @@ Item {
                 horizontalAlignment: TextEdit.AlignHCenter
             }
             QGCLabel {
-                text:           (_groundSpeed * 3.6).toFixed(1)
+                text:           _groundSpeedFact.valueString
                 font.pixelSize: ScreenTools.defaultFontPixelSize
                 font.weight:    Font.DemiBold
                 width:          parent.width

src/FlightMap/MapItems/VehicleMapItem.qml

@@ -51,7 +51,7 @@ MapQuickItem {
         transform: Rotation {
             origin.x:   vehicleIcon.width  / 2
             origin.y:   vehicleIcon.height / 2
-            angle:      vehicle ? vehicle.heading : 0
+            angle:      vehicle ? vehicle.heading.value : 0
         }
     }
 }

src/FlightMap/Widgets/QGCInstrumentWidget.qml

@@ -29,8 +29,9 @@ This file is part of the QGROUNDCONTROL project
 
 import QtQuick 2.4
 
-import QGroundControl.Controls 1.0
-import QGroundControl.ScreenTools 1.0
+import QGroundControl.Controls      1.0
+import QGroundControl.ScreenTools   1.0
+import QGroundControl.FactSystem    1.0
 
 Item {
     id:     root
@@ -41,13 +42,15 @@ Item {
     property alias  heading:        compass.heading
     property alias  rollAngle:      attitude.rollAngle
     property alias  pitchAngle:     attitude.pitchAngle
-    property real   altitude:       0
-    property real   groundSpeed:    0
-    property real   airSpeed:       0
     property real   size:           _defaultSize
     property bool   isSatellite:    false
     property bool   active:         false
 
+    property Fact   _emptyFact:         Fact { }
+    property Fact   groundSpeedFact:    _emptyFact
+    property Fact   airSpeedFact:       _emptyFact
+    property Fact   altitudeFact:       _emptyFact
+
     property real   _defaultSize:   ScreenTools.defaultFontPixelSize * (9)
 
     property real   _sizeRatio:     ScreenTools.isTinyScreen ? (size / _defaultSize) * 0.5 : size / _defaultSize
@@ -84,7 +87,7 @@ Item {
                 anchors.horizontalCenter: parent.horizontalCenter
             }
             QGCLabel {
-                text:           "Altitude (m)"
+                text:           altitudeFact.shortDescription + " (" + altitudeFact.units + ")"
                 font.pixelSize: _labelFontSize
                 width:          parent.width
                 height:         _labelFontSize
@@ -92,7 +95,7 @@ Item {
                 horizontalAlignment: TextEdit.AlignHCenter
             }
             QGCLabel {
-                text:           altitude < 10000 ? altitude.toFixed(1) : altitude.toFixed(0)
+                text:           altitudeFact.valueString
                 font.pixelSize: _bigFontSize
                 font.weight:    Font.DemiBold
                 width:          parent.width
@@ -105,25 +108,25 @@ Item {
                 width:          parent.width * 0.9
                 color:          isSatellite ? Qt.rgba(0,0,0,0.25) : Qt.rgba(1,1,1,0.25)
                 anchors.horizontalCenter: parent.horizontalCenter
-                visible:        airSpeed <= 0 && !ScreenTools.isTinyScreen
+                visible:        airSpeedFact.value <= 0 && !ScreenTools.isTinyScreen
             }
             QGCLabel {
-                text:           "Ground Speed (km/h)"
+                text:           groundSpeedFact.shortDescription + " (" + groundSpeedFact.units + ")"
                 font.pixelSize: _labelFontSize
                 width:          parent.width
                 height:         _labelFontSize
                 color:          isSatellite ? "black" : "white"
                 horizontalAlignment: TextEdit.AlignHCenter
-                visible:        airSpeed <= 0 && !ScreenTools.isTinyScreen
+                visible:        airSpeedFact.value <= 0 && !ScreenTools.isTinyScreen
             }
             QGCLabel {
-                text:           (groundSpeed * 3.6).toFixed(1)
+                text:           groundSpeedFact.valueString
                 font.pixelSize: _normalFontSize
                 font.weight:    Font.DemiBold
                 width:          parent.width
                 color:          isSatellite ? "black" : "white"
                 horizontalAlignment: TextEdit.AlignHCenter
-                visible:        airSpeed <= 0 && !ScreenTools.isTinyScreen
+                visible:        airSpeedFact.value <= 0 && !ScreenTools.isTinyScreen
             }
             //-- Air Speed
             Rectangle {
@@ -131,24 +134,24 @@ Item {
                 width:          parent.width * 0.9
                 color:          isSatellite ? Qt.rgba(0,0,0,0.25) : Qt.rgba(1,1,1,0.25)
                 anchors.horizontalCenter: parent.horizontalCenter
-                visible:        airSpeed > 0 && !ScreenTools.isTinyScreen
+                visible:        airSpeedFact.value > 0 && !ScreenTools.isTinyScreen
             }
             QGCLabel {
-                text:           "Air Speed (km/h)"
+                text:           airSpeedFact.shortDescription + " (" + airSpeedFact.units + ")"
                 font.pixelSize: _labelFontSize
                 width:          parent.width
                 height:         _labelFontSize
                 color:          isSatellite ? "black" : "white"
-                visible:        airSpeed > 0 && !ScreenTools.isTinyScreen
+                visible:        airSpeedFact.value > 0 && !ScreenTools.isTinyScreen
                 horizontalAlignment: TextEdit.AlignHCenter
             }
             QGCLabel {
-                text:           (airSpeed * 3.6).toFixed(1)
+                text:           airSpeedFact.valueString
                 font.pixelSize: _normalFontSize
                 font.weight:    Font.DemiBold
                 width:          parent.width
                 color:          isSatellite ? "black" : "white"
-                visible:        airSpeed > 0 && !ScreenTools.isTinyScreen
+                visible:        airSpeedFact.value > 0 && !ScreenTools.isTinyScreen
                 horizontalAlignment: TextEdit.AlignHCenter
             }
             //-- Compass

src/JsonHelper.cc

@@ -24,6 +24,9 @@ This file is part of the QGROUNDCONTROL project
 
 #include <QJsonArray>
 
+const char* JsonHelper::_enumStringsJsonKey =   "enumStrings";
+const char* JsonHelper::_enumValuesJsonKey =    "enumValues";
+
 bool JsonHelper::validateRequiredKeys(const QJsonObject& jsonObject, const QStringList& keys, QString& errorString)
 {
     QString missingKeys;
@@ -71,3 +74,30 @@ bool JsonHelper::toQGeoCoordinate(const QJsonValue& jsonValue, QGeoCoordinate& c
 
     return true;
 }
+
+bool JsonHelper::validateKeyTypes(QJsonObject& jsonObject, const QStringList& keys, const QList<QJsonValue::Type>& types, QString& errorString)
+{
+    for (int i=0; i<keys.count(); i++) {
+        if (jsonObject.contains(keys[i])) {
+            if (jsonObject.value(keys[i]).type() != types[i]) {
+                errorString  = QString("Incorrect type key:type:expected %1 %2 %3").arg(keys[i]).arg(jsonObject.value(keys[i]).type()).arg(types[i]);
+                return false;
+            }
+        }
+    }
+
+    return true;
+}
+
+bool JsonHelper::parseEnum(QJsonObject& jsonObject, QStringList& enumStrings, QStringList& enumValues, QString& errorString)
+{
+    enumStrings = jsonObject.value(_enumStringsJsonKey).toString().split(",", QString::SkipEmptyParts);
+    enumValues = jsonObject.value(_enumValuesJsonKey).toString().split(",", QString::SkipEmptyParts);
+
+    if (enumStrings.count() != enumValues.count()) {
+        errorString = QString("enum strings/values count mismatch: %1");
+        return false;
+    }
+
+    return true;
+}

src/JsonHelper.h

@@ -31,7 +31,12 @@ class JsonHelper
 {
 public:
     static bool validateRequiredKeys(const QJsonObject& jsonObject, const QStringList& keys, QString& errorString);
+    static bool validateKeyTypes(QJsonObject& jsonObject, const QStringList& keys, const QList<QJsonValue::Type>& types, QString& errorString);
     static bool toQGeoCoordinate(const QJsonValue& jsonValue, QGeoCoordinate& coordinate, bool altitudeRequired, QString& errorString);
+    static bool parseEnum(QJsonObject& jsonObject, QStringList& enumStrings, QStringList& enumValues, QString& errorString);
+
+    static const char*  _enumStringsJsonKey;
+    static const char*  _enumValuesJsonKey;
 };
 
 #endif

src/Vehicle/BatteryFact.json

@@ -0,0 +1,69 @@
+{
+    "version": 1,
+
+    "properties": [
+        {
+            "name":             "roll",
+            "shortDescription": "Roll",
+            "type":             "double",
+            "decimalPlaces":    1,
+            "units":            "degrees"
+        },
+        {
+            "name":             "pitch",
+            "shortDescription": "Pitch",
+            "type":             "double",
+            "decimalPlaces":    1,
+            "units":            "degrees"
+        },
+        {
+            "name":             "heading",
+            "shortDescription": "Heading",
+            "type":             "double",
+            "decimalPlaces":    0,
+            "units":            "degrees"
+        },
+        {
+            "name":             "groundSpeed",
+            "shortDescription": "Ground Speed",
+            "type":             "double",
+            "decimalPlaces":    1,
+            "units":            "m/s"
+        },
+        {
+            "name":             "airSpeed",
+            "shortDescription": "Air Speed",
+            "type":             "double",
+            "decimalPlaces":    1,
+            "units":            "m/s"
+        },
+        {
+            "name":             "climbRate",
+            "shortDescription": "Climb Rate",
+            "type":             "double",
+            "decimalPlaces":    1,
+            "units":            "m/s"
+        },
+        {
+            "name":             "altitudeRelative",
+            "shortDescription": "Altitude",
+            "type":             "double",
+            "decimalPlaces":    1,
+            "units":            "m"
+        },
+        {
+            "name":             "altitudeQGS84",
+            "shortDescription": "Altitude",
+            "type":             "double",
+            "decimalPlaces":    1,
+            "units":            "m"
+        },
+        {
+            "name":             "altitudeAMSL",
+            "shortDescription": "Altitude",
+            "type":             "double",
+            "decimalPlaces":    1,
+            "units":            "m"
+        }
+    ]
+}

src/Vehicle/GPSFact.json

@@ -0,0 +1,39 @@
+{
+    "version": 1,
+
+    "properties": [
+        {
+            "name":             "hdop",
+            "shortDescription": "HDOP",
+            "type":             "double",
+            "decimalPlaces":    1
+        },
+        {
+            "name":             "vdop",
+            "shortDescription": "VDOP",
+            "type":             "double",
+            "decimalPlaces":    1
+        },
+        {
+            "name":             "courseOverGround",
+            "shortDescription": "Course Over Ground",
+            "type":             "double",
+            "decimalPlaces":    1,
+            "units":            "degrees"
+        },
+        {
+            "name":             "lock",
+            "shortDescription": "GPS Lock",
+            "type":             "uint32",
+            "enumStrings":      "None,None,2D Lock,3D Lock,3D DGPS Lock,3D RTK GPS Lock",
+            "enumValues":       "0,1,2,3,4,5",
+            "decimalPlaces":    0
+        },
+        {
+            "name":             "count",
+            "shortDescription": "Sat Count",
+            "type":             "double",
+            "decimalPlaces":    0
+        }
+    ]
+}

src/Vehicle/Vehicle.cc

@@ -46,6 +46,23 @@ const char* Vehicle::_settingsGroup =               "Vehicle%1";        // %1 re
 const char* Vehicle::_joystickModeSettingsKey =     "JoystickMode";
 const char* Vehicle::_joystickEnabledSettingsKey =  "JoystickEnabled";
 
+const char* Vehicle::_rollFactName =                "roll";
+const char* Vehicle::_pitchFactName =               "pitch";
+const char* Vehicle::_headingFactName =             "heading";
+const char* Vehicle::_airSpeedFactName =            "airSpeed";
+const char* Vehicle::_groundSpeedFactName =         "groundSpeed";
+const char* Vehicle::_climbRateFactName =           "climbRate";
+const char* Vehicle::_altitudeRelativeFactName =    "altitudeRelative";
+const char* Vehicle::_altitudeWGS84FactName =       "altitudeWGS84";
+const char* Vehicle::_altitudeAMSLFactName =        "altitudeAMSL";
+const char* Vehicle::_gpsFactGroupName =            "gps";
+
+const char* VehicleGPSFactGroup::_hdopFactName =                "hdop";
+const char* VehicleGPSFactGroup::_vdopFactName =                "vdop";
+const char* VehicleGPSFactGroup::_courseOverGroundFactName =    "courseOverGround";
+const char* VehicleGPSFactGroup::_countFactName =               "count";
+const char* VehicleGPSFactGroup::_lockFactName =                "lock";
+
 Vehicle::Vehicle(LinkInterface*             link,
                  int                        vehicleId,
                  MAV_AUTOPILOT              firmwareType,
@@ -53,7 +70,8 @@ Vehicle::Vehicle(LinkInterface*             link,
                  FirmwarePluginManager*     firmwarePluginManager,
                  AutoPilotPluginManager*    autopilotPluginManager,
                  JoystickManager*           joystickManager)
-    : _id(vehicleId)
+    : FactGroup(_vehicleUIUpdateRateMSecs, ":/json/Vehicle/VehicleFact.json")
+    , _id(vehicleId)
     , _active(false)
     , _firmwareType(firmwareType)
     , _vehicleType(vehicleType)
@@ -72,15 +90,6 @@ Vehicle::Vehicle(LinkInterface*             link,
     , _currentWarningCount(0)
     , _currentNormalCount(0)
     , _currentMessageType(MessageNone)
-    , _roll(0.0f)
-    , _pitch(0.0f)
-    , _heading(0.0f)
-    , _altitudeAMSL(0.0f)
-    , _altitudeWGS84(0.0f)
-    , _altitudeRelative(0.0f)
-    , _groundSpeed(0.0f)
-    , _airSpeed(0.0f)
-    , _climbRate(0.0f)
     , _navigationAltitudeError(0.0f)
     , _navigationSpeedError(0.0f)
     , _navigationCrosstrackError(0.0f)
@@ -89,11 +98,6 @@ Vehicle::Vehicle(LinkInterface*             link,
     , _batteryVoltage(-1.0f)
     , _batteryPercent(0.0)
     , _batteryConsumed(-1.0)
-    , _satelliteCount(-1)
-    , _satRawHDOP(1e10f)
-    , _satRawVDOP(1e10f)
-    , _satRawCOG(0.0)
-    , _satelliteLock(0)
     , _updateCount(0)
     , _rcRSSI(0)
     , _rcRSSIstore(100.0)
@@ -118,6 +122,16 @@ Vehicle::Vehicle(LinkInterface*             link,
     , _messageSeq(0)
     , _compID(0)
     , _heardFrom(false)
+    , _rollFact             (0, _rollFactName,              FactMetaData::valueTypeDouble)
+    , _pitchFact            (0, _pitchFactName,             FactMetaData::valueTypeDouble)
+    , _headingFact          (0, _headingFactName,           FactMetaData::valueTypeDouble)
+    , _groundSpeedFact      (0, _groundSpeedFactName,       FactMetaData::valueTypeDouble)
+    , _airSpeedFact         (0, _airSpeedFactName,          FactMetaData::valueTypeDouble)
+    , _climbRateFact        (0, _climbRateFactName,         FactMetaData::valueTypeDouble)
+    , _altitudeRelativeFact (0, _altitudeRelativeFactName,  FactMetaData::valueTypeDouble)
+    , _altitudeWGS84Fact    (0, _altitudeWGS84FactName,     FactMetaData::valueTypeDouble)
+    , _altitudeAMSLFact     (0, _altitudeAMSLFactName,      FactMetaData::valueTypeDouble)
+    , _gpsFactGroup(this)
 {
     _addLink(link);
 
@@ -155,15 +169,6 @@ Vehicle::Vehicle(LinkInterface*             link,
     connect(&_connectionLostTimer, &QTimer::timeout, this, &Vehicle::_connectionLostTimeout);
 
     _mav = uas();
-    // Reset satellite data (no GPS)
-    _satelliteCount = -1;
-    _satRawHDOP     = 1e10f;
-    _satRawVDOP     = 1e10f;
-    _satRawCOG      = 0.0;
-    emit satRawHDOPChanged();
-    emit satRawVDOPChanged();
-    emit satRawCOGChanged();
-    emit satelliteCountChanged();
 
     // Listen for system messages
     connect(qgcApp()->toolbox()->uasMessageHandler(), &UASMessageHandler::textMessageCountChanged,  this, &Vehicle::_handleTextMessage);
@@ -179,15 +184,6 @@ Vehicle::Vehicle(LinkInterface*             link,
     connect(_mav, &UASInterface::NavigationControllerDataChanged,   this, &Vehicle::_updateNavigationControllerData);
     connect(_mav, &UASInterface::batteryChanged,                    this, &Vehicle::_updateBatteryRemaining);
     connect(_mav, &UASInterface::batteryConsumedChanged,            this, &Vehicle::_updateBatteryConsumedChanged);
-    connect(_mav, &UASInterface::localizationChanged,               this, &Vehicle::_setSatLoc);
-    UAS* pUas = dynamic_cast<UAS*>(_mav);
-    if(pUas) {
-        _setSatelliteCount(pUas->getSatelliteCount(), QString(""));
-        connect(pUas, &UAS::satelliteCountChanged,  this, &Vehicle::_setSatelliteCount);
-        connect(pUas, &UAS::satRawHDOPChanged,      this, &Vehicle::_setSatRawHDOP);
-        connect(pUas, &UAS::satRawVDOPChanged,      this, &Vehicle::_setSatRawVDOP);
-        connect(pUas, &UAS::satRawCOGChanged,       this, &Vehicle::_setSatRawCOG);
-    }
 
     _loadSettings();
 
@@ -205,6 +201,21 @@ Vehicle::Vehicle(LinkInterface*             link,
 
     _mapTrajectoryTimer.setInterval(_mapTrajectoryMsecsBetweenPoints);
     connect(&_mapTrajectoryTimer, &QTimer::timeout, this, &Vehicle::_addNewMapTrajectoryPoint);
+
+    // Build FactGroup object model
+
+    _addFact(&_rollFact,                _rollFactName);
+    _addFact(&_pitchFact,               _pitchFactName);
+    _addFact(&_headingFact,             _headingFactName);
+    _addFact(&_groundSpeedFact,         _groundSpeedFactName);
+    _addFact(&_airSpeedFact,            _airSpeedFactName);
+    _addFact(&_climbRateFact,           _climbRateFactName);
+    _addFact(&_altitudeRelativeFact,    _altitudeRelativeFactName);
+    _addFact(&_altitudeWGS84Fact,       _altitudeWGS84FactName);
+    _addFact(&_altitudeAMSLFact,        _altitudeAMSLFactName);
+
+    _addFactGroup(&_gpsFactGroup, _gpsFactGroupName);
+    _gpsFactGroup.setVehicle(this);
 }
 
 Vehicle::~Vehicle()
@@ -564,50 +575,21 @@ void Vehicle::setLongitude(double longitude){
 void Vehicle::_updateAttitude(UASInterface*, double roll, double pitch, double yaw, quint64)
 {
     if (isinf(roll)) {
-        _roll = std::numeric_limits<double>::quiet_NaN();
+        _rollFact.setRawValue(0);
     } else {
-        float rolldeg = _oneDecimal(roll * (180.0 / M_PI));
-        if (fabs(roll - rolldeg) > 0.25) {
-            _roll = rolldeg;
-            if(_refreshTimer->isActive()) {
-                emit rollChanged();
-            }
-        }
-        if(_roll != rolldeg) {
-            _roll = rolldeg;
-            _addChange(ROLL_CHANGED);
-        }
+        _rollFact.setRawValue(roll * (180.0 / M_PI));
     }
     if (isinf(pitch)) {
-        _pitch = std::numeric_limits<double>::quiet_NaN();
+        _pitchFact.setRawValue(0);
     } else {
-        float pitchdeg = _oneDecimal(pitch * (180.0 / M_PI));
-        if (fabs(pitch - pitchdeg) > 0.25) {
-            _pitch = pitchdeg;
-            if(_refreshTimer->isActive()) {
-                emit pitchChanged();
-            }
-        }
-        if(_pitch != pitchdeg) {
-            _pitch = pitchdeg;
-            _addChange(PITCH_CHANGED);
-        }
+        _pitchFact.setRawValue(pitch * (180.0 / M_PI));
     }
     if (isinf(yaw)) {
-        _heading = std::numeric_limits<double>::quiet_NaN();
+        _headingFact.setRawValue(0);
     } else {
-        yaw = _oneDecimal(yaw * (180.0 / M_PI));
+        yaw = yaw * (180.0 / M_PI);
         if (yaw < 0) yaw += 360;
-        if (fabs(_heading - yaw) > 0.25) {
-            _heading = yaw;
-            if(_refreshTimer->isActive()) {
-                emit headingChanged();
-            }
-        }
-        if(_heading != yaw) {
-            _heading = yaw;
-            _addChange(HEADING_CHANGED);
-        }
+        _headingFact.setRawValue(yaw);
     }
 }
 
@@ -618,75 +600,15 @@ void Vehicle::_updateAttitude(UASInterface* uas, int, double roll, double pitch,
 
 void Vehicle::_updateSpeed(UASInterface*, double groundSpeed, double airSpeed, quint64)
 {
-    groundSpeed = _oneDecimal(groundSpeed);
-    if (fabs(_groundSpeed - groundSpeed) > 0.5) {
-        _groundSpeed = groundSpeed;
-        if(_refreshTimer->isActive()) {
-            emit groundSpeedChanged();
-        }
-    }
-    airSpeed = _oneDecimal(airSpeed);
-    if (fabs(_airSpeed - airSpeed) > 0.5) {
-        _airSpeed = airSpeed;
-        if(_refreshTimer->isActive()) {
-            emit airSpeedChanged();
-        }
-    }
-    if(_groundSpeed != groundSpeed) {
-        _groundSpeed = groundSpeed;
-        _addChange(GROUNDSPEED_CHANGED);
-    }
-    if(_airSpeed != airSpeed) {
-        _airSpeed = airSpeed;
-        _addChange(AIRSPEED_CHANGED);
-    }
+    _groundSpeedFact.setRawValue(groundSpeed);
+    _airSpeedFact.setRawValue(airSpeed);
 }
 
 void Vehicle::_updateAltitude(UASInterface*, double altitudeAMSL, double altitudeWGS84, double altitudeRelative, double climbRate, quint64) {
-    altitudeAMSL = _oneDecimal(altitudeAMSL);
-    if (fabs(_altitudeAMSL - altitudeAMSL) > 0.5) {
-        _altitudeAMSL = altitudeAMSL;
-        if(_refreshTimer->isActive()) {
-            emit altitudeAMSLChanged();
-        }
-    }
-    altitudeWGS84 = _oneDecimal(altitudeWGS84);
-    if (fabs(_altitudeWGS84 - altitudeWGS84) > 0.5) {
-        _altitudeWGS84 = altitudeWGS84;
-        if(_refreshTimer->isActive()) {
-            emit altitudeWGS84Changed();
-        }
-    }
-    altitudeRelative = _oneDecimal(altitudeRelative);
-    if (fabs(_altitudeRelative - altitudeRelative) > 0.5) {
-        _altitudeRelative = altitudeRelative;
-        if(_refreshTimer->isActive()) {
-            emit altitudeRelativeChanged();
-        }
-    }
-    climbRate = _oneDecimal(climbRate);
-    if (fabs(_climbRate - climbRate) > 0.5) {
-        _climbRate = climbRate;
-        if(_refreshTimer->isActive()) {
-            emit climbRateChanged();
-        }
-    }
-    if(_altitudeAMSL != altitudeAMSL) {
-        _altitudeAMSL = altitudeAMSL;
-        _addChange(ALTITUDEAMSL_CHANGED);
-    }
-    if(_altitudeWGS84 != altitudeWGS84) {
-        _altitudeWGS84 = altitudeWGS84;
-        _addChange(ALTITUDEWGS84_CHANGED);
-    }
-    if(_altitudeRelative != altitudeRelative) {
-        _altitudeRelative = altitudeRelative;
-        _addChange(ALTITUDERELATIVE_CHANGED);
-    }
-    if(_climbRate != climbRate) {
-        _climbRate = climbRate;
-        _addChange(CLIMBRATE_CHANGED);
-    }
+    _altitudeAMSLFact.setRawValue(altitudeAMSL);
+    _altitudeWGS84Fact.setRawValue(altitudeWGS84);
+    _altitudeRelativeFact.setRawValue(altitudeRelative);
+    _climbRateFact.setRawValue(climbRate);
 }
 
 void Vehicle::_updateNavigationControllerErrors(UASInterface*, double altitudeError, double speedError, double xtrackError) {
@@ -705,19 +627,6 @@ void Vehicle::_updateNavigationControllerData(UASInterface *uas, float, float, f
  * Internal
  */
 
-void Vehicle::_addChange(int id)
-{
-    if(!_changes.contains(id)) {
-        _changes.append(id);
-    }
-}
-
-float Vehicle::_oneDecimal(float value)
-{
-    int i = (value * 10);
-    return (float)i / 10.0;
-}
-
 void Vehicle::_checkUpdate()
 {
     // Update current location
@@ -729,49 +638,6 @@ void Vehicle::_checkUpdate()
             setLongitude(_mav->getLongitude());
         }
     }
-    // The timer rate is 20Hz for the coordinates above. These below we only check
-    // twice a second.
-    if(++_updateCount > 9) {
-        _updateCount = 0;
-        // Check for changes
-        // Significant changes, that is, whole number changes, are updated immediatelly.
-        // For every message however, we set a flag for what changed and this timer updates
-        // them to bring everything up-to-date. This prevents an avalanche of UI updates.
-        foreach(int i, _changes) {
-            switch (i) {
-                case ROLL_CHANGED:
-                    emit rollChanged();
-                    break;
-                case PITCH_CHANGED:
-                    emit pitchChanged();
-                    break;
-                case HEADING_CHANGED:
-                    emit headingChanged();
-                    break;
-                case GROUNDSPEED_CHANGED:
-                    emit groundSpeedChanged();
-                    break;
-                case AIRSPEED_CHANGED:
-                    emit airSpeedChanged();
-                    break;
-                case CLIMBRATE_CHANGED:
-                    emit climbRateChanged();
-                    break;
-                case ALTITUDERELATIVE_CHANGED:
-                    emit altitudeRelativeChanged();
-                    break;
-                case ALTITUDEWGS84_CHANGED:
-                    emit altitudeWGS84Changed();
-                    break;
-                case ALTITUDEAMSL_CHANGED:
-                    emit altitudeAMSLChanged();
-                    break;
-                default:
-                    break;
-            }
-        }
-        _changes.clear();
-    }
 }
 
 QString Vehicle::getMavIconColor()
@@ -837,54 +703,6 @@ void Vehicle::_updateState(UASInterface*, QString name, QString)
     }
 }
 
-void Vehicle::_setSatelliteCount(double val, QString)
-{
-    // I'm assuming that a negative value or over 99 means there is no GPS
-    if(val < 0.0)  val = -1.0;
-    if(val > 99.0) val = -1.0;
-    if(_satelliteCount != (int)val) {
-        _satelliteCount = (int)val;
-        emit satelliteCountChanged();
-    }
-}
-
-void Vehicle::_setSatRawHDOP(double val)
-{
-    if(_satRawHDOP != val) {
-        _satRawHDOP = val;
-        emit satRawHDOPChanged();
-    }
-}
-
-void Vehicle::_setSatRawVDOP(double val)
-{
-    if(_satRawVDOP != val) {
-        _satRawVDOP = val;
-        emit satRawVDOPChanged();
-    }
-}
-
-void Vehicle::_setSatRawCOG(double val)
-{
-    if(_satRawCOG != val) {
-        _satRawCOG = val;
-        emit satRawCOGChanged();
-    }
-}
-
-void Vehicle::_setSatLoc(UASInterface*, int fix)
-{
-    // fix 0: lost, 1: at least one satellite, but no GPS fix, 2: 2D lock, 3: 3D lock
-    if(_satelliteLock != fix) {
-        if (fix > 2) {
-            _coordinateValid = true;
-            emit coordinateValidChanged(true);
-        }
-        _satelliteLock = fix;
-        emit satelliteLockChanged();
-    }
-}
-
 void Vehicle::_handleTextMessage(int newCount)
 {
     // Reset?
@@ -1358,3 +1176,86 @@ bool Vehicle::multiRotor(void) const
         return false;
     }
 }
+
+void Vehicle::_setCoordinateValid(bool coordinateValid)
+{
+    if (coordinateValid != _coordinateValid) {
+        _coordinateValid = coordinateValid;
+        emit coordinateValidChanged(_coordinateValid);
+    }
+}
+
+
+VehicleGPSFactGroup::VehicleGPSFactGroup(QObject* parent)
+    : FactGroup(1000, ":/json/Vehicle/GPSFact.json", parent)
+    , _vehicle(NULL)
+    , _hdopFact             (0, _hdopFactName,              FactMetaData::valueTypeDouble)
+    , _vdopFact             (0, _vdopFactName,              FactMetaData::valueTypeDouble)
+    , _courseOverGroundFact (0, _courseOverGroundFactName,  FactMetaData::valueTypeDouble)
+    , _countFact            (0, _countFactName,             FactMetaData::valueTypeInt32)
+    , _lockFact             (0, _lockFactName,              FactMetaData::valueTypeInt32)
+{
+    // Build FactGroup object model
+
+    _addFact(&_hdopFact,                _hdopFactName);
+    _addFact(&_vdopFact,                _vdopFactName);
+    _addFact(&_courseOverGroundFact,    _courseOverGroundFactName);
+    _addFact(&_lockFact,                _lockFactName);
+    _addFact(&_countFact,               _countFactName);
+}
+
+void VehicleGPSFactGroup::setVehicle(Vehicle* vehicle)
+{
+    _vehicle = vehicle;
+
+#if 0
+    // Reset satellite data (no GPS)
+    _satelliteCount = -1;
+    _satRawHDOP     = 1e10f;
+    _satRawVDOP     = 1e10f;
+    _satRawCOG      = 0.0;
+#endif
+
+    connect(_vehicle->uas(), &UASInterface::localizationChanged, this, &VehicleGPSFactGroup::_setSatLoc);
+
+    UAS* pUas = dynamic_cast<UAS*>(_vehicle->uas());
+    connect(pUas, &UAS::satelliteCountChanged,  this, &VehicleGPSFactGroup::_setSatelliteCount);
+    connect(pUas, &UAS::satRawHDOPChanged,      this, &VehicleGPSFactGroup::_setSatRawHDOP);
+    connect(pUas, &UAS::satRawVDOPChanged,      this, &VehicleGPSFactGroup::_setSatRawVDOP);
+    connect(pUas, &UAS::satRawCOGChanged,       this, &VehicleGPSFactGroup::_setSatRawCOG);
+}
+
+void VehicleGPSFactGroup::_setSatelliteCount(double val, QString)
+{
+    // I'm assuming that a negative value or over 99 means there is no GPS
+    if(val < 0.0)  val = -1.0;
+    if(val > 99.0) val = -1.0;
+
+    _countFact.setRawValue(val);
+}
+
+void VehicleGPSFactGroup::_setSatRawHDOP(double val)
+{
+    _hdopFact.setRawValue(val);
+}
+
+void VehicleGPSFactGroup::_setSatRawVDOP(double val)
+{
+    _vdopFact.setRawValue(val);
+}
+
+void VehicleGPSFactGroup::_setSatRawCOG(double val)
+{
+    _courseOverGroundFact.setRawValue(val);
+}
+
+void VehicleGPSFactGroup::_setSatLoc(UASInterface*, int fix)
+{
+    _lockFact.setRawValue(fix);
+
+    // fix 0: lost, 1: at least one satellite, but no GPS fix, 2: 2D lock, 3: 3D lock
+    if (fix > 2) {
+        _vehicle->_setCoordinateValid(true);
+    }
+}
+

src/Vehicle/Vehicle.h

@@ -30,6 +30,7 @@
 #include <QObject>
 #include <QGeoCoordinate>
 
+#include "FactGroup.h"
 #include "LinkInterface.h"
 #include "QGCMAVLink.h"
 #include "MissionItem.h"
@@ -50,7 +51,52 @@ class UASMessage;
 
 Q_DECLARE_LOGGING_CATEGORY(VehicleLog)
 
-class Vehicle : public QObject
+class Vehicle;
+
+class VehicleGPSFactGroup : public FactGroup
+{
+    Q_OBJECT
+
+public:
+    VehicleGPSFactGroup(QObject* parent = NULL);
+
+    Q_PROPERTY(Fact* hdop               READ hdop               CONSTANT)
+    Q_PROPERTY(Fact* vdop               READ vdop               CONSTANT)
+    Q_PROPERTY(Fact* courseOverGround   READ courseOverGround   CONSTANT)
+    Q_PROPERTY(Fact* count              READ count              CONSTANT)
+    Q_PROPERTY(Fact* lock               READ lock               CONSTANT)
+
+    Fact* hdop(void)                { return &_hdopFact; }
+    Fact* vdop(void)                { return &_vdopFact; }
+    Fact* courseOverGround(void)    { return &_courseOverGroundFact; }
+    Fact* count(void)               { return &_countFact; }
+    Fact* lock(void)                { return &_lockFact; }
+
+    void setVehicle(Vehicle* vehicle);
+
+private slots:
+    void _setSatelliteCount(double val, QString);
+    void _setSatRawHDOP(double val);
+    void _setSatRawVDOP(double val);
+    void _setSatRawCOG(double val);
+    void _setSatLoc(UASInterface*, int fix);
+
+private:
+    Vehicle*    _vehicle;
+    Fact        _hdopFact;
+    Fact        _vdopFact;
+    Fact        _courseOverGroundFact;
+    Fact        _countFact;
+    Fact        _lockFact;
+
+    static const char* _hdopFactName;
+    static const char* _vdopFactName;
+    static const char* _courseOverGroundFactName;
+    static const char* _countFactName;
+    static const char* _lockFactName;
+};
+
+class Vehicle : public FactGroup
 {
     Q_OBJECT
 
@@ -78,26 +124,12 @@ public:
     Q_PROPERTY(bool                 hilMode                 READ hilMode            WRITE setHilMode    NOTIFY hilModeChanged)
     Q_PROPERTY(bool                 missingParameters       READ missingParameters                      NOTIFY missingParametersChanged)
     Q_PROPERTY(QmlObjectListModel*  trajectoryPoints        READ trajectoryPoints                       CONSTANT)
-    Q_PROPERTY(float                roll                    READ roll                                   NOTIFY rollChanged)
-    Q_PROPERTY(float                pitch                   READ pitch                                  NOTIFY pitchChanged)
-    Q_PROPERTY(float                heading                 READ heading                                NOTIFY headingChanged)
-    Q_PROPERTY(float                groundSpeed             READ groundSpeed                            NOTIFY groundSpeedChanged)
-    Q_PROPERTY(float                airSpeed                READ airSpeed                               NOTIFY airSpeedChanged)
-    Q_PROPERTY(float                climbRate               READ climbRate                              NOTIFY climbRateChanged)
-    Q_PROPERTY(float                altitudeRelative        READ altitudeRelative                       NOTIFY altitudeRelativeChanged)
-    Q_PROPERTY(float                altitudeWGS84           READ altitudeWGS84                          NOTIFY altitudeWGS84Changed)
-    Q_PROPERTY(float                altitudeAMSL            READ altitudeAMSL                           NOTIFY altitudeAMSLChanged)
     Q_PROPERTY(float                latitude                READ latitude                               NOTIFY coordinateChanged)
     Q_PROPERTY(float                longitude               READ longitude                              NOTIFY coordinateChanged)
     Q_PROPERTY(double               batteryVoltage          READ batteryVoltage                         NOTIFY batteryVoltageChanged)
     Q_PROPERTY(double               batteryPercent          READ batteryPercent                         NOTIFY batteryPercentChanged)
     Q_PROPERTY(double               batteryConsumed         READ batteryConsumed                        NOTIFY batteryConsumedChanged)
-    Q_PROPERTY(int                  satelliteCount          READ satelliteCount                         NOTIFY satelliteCountChanged)
-    Q_PROPERTY(double               satRawHDOP              READ satRawHDOP                             NOTIFY satRawHDOPChanged)
-    Q_PROPERTY(double               satRawVDOP              READ satRawVDOP                             NOTIFY satRawVDOPChanged)
-    Q_PROPERTY(double               satRawCOG               READ satRawCOG                              NOTIFY satRawCOGChanged)
     Q_PROPERTY(QString              currentState            READ currentState                           NOTIFY currentStateChanged)
-    Q_PROPERTY(int                  satelliteLock           READ satelliteLock                          NOTIFY satelliteLockChanged)
     Q_PROPERTY(QmlObjectListModel*  missionItems            READ missionItemsModel                      CONSTANT)
     Q_PROPERTY(bool                 messageTypeNone         READ messageTypeNone                        NOTIFY messageTypeChanged)
     Q_PROPERTY(bool                 messageTypeNormal       READ messageTypeNormal                      NOTIFY messageTypeChanged)
@@ -126,6 +158,20 @@ public:
     Q_PROPERTY(bool                 multiRotor              READ multiRotor                             CONSTANT)
     Q_PROPERTY(bool                 autoDisconnect          MEMBER _autoDisconnect                      NOTIFY autoDisconnectChanged)
 
+    // FactGroup object model properties
+
+    Q_PROPERTY(Fact* roll               READ roll               CONSTANT)
+    Q_PROPERTY(Fact* pitch              READ pitch              CONSTANT)
+    Q_PROPERTY(Fact* heading            READ heading            CONSTANT)
+    Q_PROPERTY(Fact* groundSpeed        READ groundSpeed        CONSTANT)
+    Q_PROPERTY(Fact* airSpeed           READ airSpeed           CONSTANT)
+    Q_PROPERTY(Fact* climbRate          READ climbRate          CONSTANT)
+    Q_PROPERTY(Fact* altitudeRelative   READ altitudeRelative   CONSTANT)
+    Q_PROPERTY(Fact* altitudeWGS84      READ altitudeWGS84      CONSTANT)
+    Q_PROPERTY(Fact* altitudeAMSL       READ altitudeAMSL       CONSTANT)
+
+    Q_PROPERTY(FactGroup* gps   READ gpsFactGroup CONSTANT)
+
     /// Resets link status counters
     Q_INVOKABLE void resetCounters  ();
 
@@ -147,6 +193,7 @@ public:
 
     QGeoCoordinate coordinate(void) { return _coordinate; }
     bool coordinateValid(void)      { return _coordinateValid; }
+    void _setCoordinateValid(bool coordinateValid);
     QmlObjectListModel* missionItemsModel(void);
 
     typedef enum {
@@ -239,18 +286,6 @@ public:
         MessageError
     } MessageType_t;
 
-    enum {
-        ROLL_CHANGED,
-        PITCH_CHANGED,
-        HEADING_CHANGED,
-        GROUNDSPEED_CHANGED,
-        AIRSPEED_CHANGED,
-        CLIMBRATE_CHANGED,
-        ALTITUDERELATIVE_CHANGED,
-        ALTITUDEWGS84_CHANGED,
-        ALTITUDEAMSL_CHANGED
-    };
-
     bool            messageTypeNone     () { return _currentMessageType == MessageNone; }
     bool            messageTypeNormal   () { return _currentMessageType == MessageNormal; }
     bool            messageTypeWarning  () { return _currentMessageType == MessageWarning; }
@@ -260,27 +295,13 @@ public:
     QString         formatedMessages    ();
     QString         formatedMessage     () { return _formatedMessage; }
     QString         latestError         () { return _latestError; }
-    float           roll                () { return _roll; }
-    float           pitch               () { return _pitch; }
-    float           heading             () { return _heading; }
-    float           groundSpeed         () { return _groundSpeed; }
-    float           airSpeed            () { return _airSpeed; }
-    float           climbRate           () { return _climbRate; }
-    float           altitudeRelative    () { return _altitudeRelative; }
-    float           altitudeWGS84       () { return _altitudeWGS84; }
-    float           altitudeAMSL        () { return _altitudeAMSL; }
     float           latitude            () { return _coordinate.latitude(); }
     float           longitude           () { return _coordinate.longitude(); }
     bool            mavPresent          () { return _mav != NULL; }
-    int             satelliteCount      () { return _satelliteCount; }
-    double          satRawHDOP          () { return _satRawHDOP; }
-    double          satRawVDOP          () { return _satRawVDOP; }
-    double          satRawCOG           () { return _satRawCOG; }
     double          batteryVoltage      () { return _batteryVoltage; }
     double          batteryPercent      () { return _batteryPercent; }
     double          batteryConsumed     () { return _batteryConsumed; }
     QString         currentState        () { return _currentState; }
-    int             satelliteLock       () { return _satelliteLock; }
     int             rcRSSI              () { return _rcRSSI; }
     bool            px4Firmware         () { return _firmwareType == MAV_AUTOPILOT_PX4; }
     bool            apmFirmware         () { return _firmwareType == MAV_AUTOPILOT_ARDUPILOTMEGA; }
@@ -291,6 +312,18 @@ public:
     uint            messagesSent        () { return _messagesSent; }
     uint            messagesLost        () { return _messagesLost; }
 
+    Fact* roll              (void) { return &_rollFact; }
+    Fact* heading           (void) { return &_headingFact; }
+    Fact* pitch             (void) { return &_pitchFact; }
+    Fact* airSpeed          (void) { return &_airSpeedFact; }
+    Fact* groundSpeed       (void) { return &_groundSpeedFact; }
+    Fact* climbRate         (void) { return &_climbRateFact; }
+    Fact* altitudeRelative  (void) { return &_altitudeRelativeFact; }
+    Fact* altitudeWGS84     (void) { return &_altitudeWGS84Fact; }
+    Fact* altitudeAMSL      (void) { return &_altitudeAMSLFact; }
+
+    FactGroup* gpsFactGroup(void) { return &_gpsFactGroup; }
+
     void setConnectionLostEnabled(bool connectionLostEnabled);
 
     ParameterLoader* getParameterLoader(void);
@@ -335,26 +368,12 @@ signals:
     void formatedMessagesChanged();
     void formatedMessageChanged ();
     void latestErrorChanged     ();
-    void rollChanged            ();
-    void pitchChanged           ();
-    void headingChanged         ();
-    void groundSpeedChanged     ();
-    void airSpeedChanged        ();
-    void climbRateChanged       ();
-    void altitudeRelativeChanged();
-    void altitudeWGS84Changed   ();
-    void altitudeAMSLChanged    ();
     void longitudeChanged       ();
     void batteryVoltageChanged  ();
     void batteryPercentChanged  ();
     void batteryConsumedChanged ();
     void currentConfigChanged   ();
-    void satelliteCountChanged  ();
-    void satRawHDOPChanged      ();
-    void satRawVDOPChanged      ();
-    void satRawCOGChanged       ();
     void currentStateChanged    ();
-    void satelliteLockChanged   ();
     void flowImageIndexChanged  ();
     void rcRSSIChanged          (int rcRSSI);
 
@@ -395,11 +414,6 @@ private slots:
     void _updateBatteryRemaining            (UASInterface*, double voltage, double, double percent, int);
     void _updateBatteryConsumedChanged      (UASInterface*, double current_consumed);
     void _updateState                       (UASInterface* system, QString name, QString description);
-    void _setSatelliteCount                 (double val, QString name);
-    void _setSatRawHDOP                     (double val);
-    void _setSatRawVDOP                     (double val);
-    void _setSatRawCOG                      (double val);
-    void _setSatLoc                         (UASInterface* uas, int fix);
     /** @brief A new camera image has arrived */
     void _imageReady                        (UASInterface* uas);
     void _connectionLostTimeout(void);
@@ -420,9 +434,6 @@ private:
     void _connectionActive(void);
     void _say(const QString& text, int severity);
 
-    void    _addChange                      (int id);
-    float   _oneDecimal                     (float value);
-
 private:
     int     _id;            ///< Mavlink system id
     bool    _active;
@@ -454,30 +465,15 @@ private:
     int             _currentNormalCount;
     MessageType_t   _currentMessageType;
     QString         _latestError;
-    float           _roll;
-    float           _pitch;
-    float           _heading;
-    float           _altitudeAMSL;
-    float           _altitudeWGS84;
-    float           _altitudeRelative;
-    float           _groundSpeed;
-    float           _airSpeed;
-    float           _climbRate;
     float           _navigationAltitudeError;
     float           _navigationSpeedError;
     float           _navigationCrosstrackError;
     float           _navigationTargetBearing;
     QTimer*         _refreshTimer;
-    QList<int>      _changes;
     double          _batteryVoltage;
     double          _batteryPercent;
     double          _batteryConsumed;
     QString         _currentState;
-    int             _satelliteCount;
-    double          _satRawHDOP;
-    double          _satRawVDOP;
-    double          _satRawCOG;
-    int             _satelliteLock;
     int             _updateCount;
     QString         _formatedMessage;
     int             _rcRSSI;
@@ -534,9 +530,37 @@ private:
     uint8_t             _compID;
     bool                _heardFrom;
 
+    // FactGroup facts
+
+    Fact _rollFact;
+    Fact _pitchFact;
+    Fact _headingFact;
+    Fact _groundSpeedFact;
+    Fact _airSpeedFact;
+    Fact _climbRateFact;
+    Fact _altitudeRelativeFact;
+    Fact _altitudeWGS84Fact;
+    Fact _altitudeAMSLFact;
+
+    VehicleGPSFactGroup _gpsFactGroup;
+
+    static const char* _rollFactName;
+    static const char* _pitchFactName;
+    static const char* _headingFactName;
+    static const char* _groundSpeedFactName;
+    static const char* _airSpeedFactName;
+    static const char* _climbRateFactName;
+    static const char* _altitudeRelativeFactName;
+    static const char* _altitudeWGS84FactName;
+    static const char* _altitudeAMSLFactName;
+    static const char* _gpsFactGroupName;
+
+    static const int _vehicleUIUpdateRateMSecs = 100;
+
     // Settings keys
     static const char* _settingsGroup;
     static const char* _joystickModeSettingsKey;
     static const char* _joystickEnabledSettingsKey;
+
 };
 #endif

src/Vehicle/VehicleFact.json

@@ -0,0 +1,69 @@
+{
+    "version": 1,
+
+    "properties": [
+        {
+            "name":             "roll",
+            "shortDescription": "Roll",
+            "type":             "double",
+            "decimalPlaces":    1,
+            "units":            "degrees"
+        },
+        {
+            "name":             "pitch",
+            "shortDescription": "Pitch",
+            "type":             "double",
+            "decimalPlaces":    1,
+            "units":            "degrees"
+        },
+        {
+            "name":             "heading",
+            "shortDescription": "Heading",
+            "type":             "double",
+            "decimalPlaces":    0,
+            "units":            "degrees"
+        },
+        {
+            "name":             "groundSpeed",
+            "shortDescription": "Ground Speed",
+            "type":             "double",
+            "decimalPlaces":    1,
+            "units":            "m/s"
+        },
+        {
+            "name":             "airSpeed",
+            "shortDescription": "Air Speed",
+            "type":             "double",
+            "decimalPlaces":    1,
+            "units":            "m/s"
+        },
+        {
+            "name":             "climbRate",
+            "shortDescription": "Climb Rate",
+            "type":             "double",
+            "decimalPlaces":    1,
+            "units":            "m/s"
+        },
+        {
+            "name":             "altitudeRelative",
+            "shortDescription": "Altitude",
+            "type":             "double",
+            "decimalPlaces":    1,
+            "units":            "m"
+        },
+        {
+            "name":             "altitudeWGS84",
+            "shortDescription": "Altitude",
+            "type":             "double",
+            "decimalPlaces":    1,
+            "units":            "m"
+        },
+        {
+            "name":             "altitudeAMSL",
+            "shortDescription": "Altitude",
+            "type":             "double",
+            "decimalPlaces":    1,
+            "units":            "m"
+        }
+    ]
+}

src/comm/QGCXPlaneLink.cc

@@ -933,16 +933,16 @@ void QGCXPlaneLink::setRandomPosition()
     double offLon = rand() / static_cast<double>(RAND_MAX) / 500.0 + 1.0/500.0;
     double offAlt = rand() / static_cast<double>(RAND_MAX) * 200.0 + 100.0;
 
-    if (_vehicle->altitudeAMSL() + offAlt < 0)
+    if (_vehicle->altitudeAMSL()->rawValue().toDouble() + offAlt < 0)
     {
         offAlt *= -1.0;
     }
 
     setPositionAttitude(_vehicle->latitude() + offLat,
                         _vehicle->longitude() + offLon,
-                        _vehicle->altitudeAMSL() + offAlt,
-                        _vehicle->roll(),
-                        _vehicle->pitch(),
+                        _vehicle->altitudeAMSL()->rawValue().toDouble() + offAlt,
+                        _vehicle->roll()->rawValue().toDouble(),
+                        _vehicle->pitch()->rawValue().toDouble(),
                         _vehicle->uas()->getYaw());
 }
 
@@ -957,7 +957,7 @@ void QGCXPlaneLink::setRandomAttitude()
 
     setPositionAttitude(_vehicle->latitude(),
                         _vehicle->longitude(),
-                        _vehicle->altitudeAMSL(),
+                        _vehicle->altitudeAMSL()->rawValue().toDouble(),
                         roll,
                         pitch,
                         yaw);

src/ui/toolbar/MainToolBar.qml

@@ -188,28 +188,6 @@ Rectangle {
         return colorRed;
     }
 
-    function getGpsLockStatus() {
-        if(activeVehicle) {
-            if(activeVehicle.satelliteLock < 2) {
-                return "No Satellite Lock"
-            }
-            if(activeVehicle.satelliteLock == 2) {
-                return "2D Lock"
-            }
-            if(activeVehicle.satelliteLock == 3) {
-                return "3D Lock"
-            }
-            if(activeVehicle.satelliteLock == 4) {
-                return "3D DGPS Lock"
-            }
-            if(activeVehicle.satelliteLock == 5) {
-                return "3D RTK GPS Lock"
-            }
-            return "Unkown Lock Type (" + activeVehicle.satelliteLock + ")"
-        }
-        return "N/A"
-    }
-
     Component.onCompleted: {
         //-- TODO: Get this from the actual state
         flyButton.checked = true
@@ -232,14 +210,14 @@ Rectangle {
                 anchors.centerIn:   parent
                 QGCLabel {
                     id:         gpsLabel
-                    text:       (activeVehicle && activeVehicle.satelliteCount >= 0) ? "GPS Status" : "GPS Data Unavailable"
+                    text:       (activeVehicle && activeVehicle.gps.count.value >= 0) ? "GPS Status" : "GPS Data Unavailable"
                     font.weight:Font.DemiBold
                     color:      colorWhite
                     anchors.horizontalCenter: parent.horizontalCenter
                 }
                 GridLayout {
                     id:                 gpsGrid
-                    visible:            (activeVehicle && activeVehicle.satelliteCount >= 0)
+                    visible:            (activeVehicle && activeVehicle.gps.count.value >= 0)
                     anchors.margins:    ScreenTools.defaultFontPixelHeight
                     columnSpacing:      ScreenTools.defaultFontPixelWidth
                     anchors.horizontalCenter: parent.horizontalCenter
@@ -249,7 +227,7 @@ Rectangle {
                         color:  colorWhite
                     }
                     QGCLabel {
-                        text:   activeVehicle ? (activeVehicle.satelliteCount) : "N/A"
+                        text:   activeVehicle ? activeVehicle.gps.count.valueString : "N/A"
                         color:  colorWhite
                     }
                     QGCLabel {
@@ -257,7 +235,7 @@ Rectangle {
                         color:  colorWhite
                     }
                     QGCLabel {
-                        text:   getGpsLockStatus()
+                        text:   activeVehicle ? activeVehicle.gps.lock.enumStringValue : "N/A"
                         color:  colorWhite
                     }
                     QGCLabel {
@@ -265,7 +243,7 @@ Rectangle {
                         color:  colorWhite
                     }
                     QGCLabel {
-                        text:   activeVehicle ? (activeVehicle.satRawHDOP < 10000 ? activeVehicle.satRawHDOP.toFixed(0) : "N/A") : "N/A"
+                        text:   activeVehicle ? (activeVehicle.gps.hdop.value < 10000 ? activeVehicle.gps.hdop.valueString : "N/A") : "N/A"
                         color:  colorWhite
                     }
                     QGCLabel {
@@ -273,7 +251,7 @@ Rectangle {
                         color:  colorWhite
                     }
                     QGCLabel {
-                        text:   activeVehicle ? (activeVehicle.satRawVDOP < 10000 ? activeVehicle.satRawVDOP.toFixed(0) : "N/A") : "N/A"
+                        text:   activeVehicle ? (activeVehicle.gps.vdop.value < 10000 ? activeVehicle.gps.vdop.valueString : "N/A") : "N/A"
                         color:  colorWhite
                     }
                     QGCLabel {
@@ -281,7 +259,7 @@ Rectangle {
                         color:  colorWhite
                     }
                     QGCLabel {
-                        text:   activeVehicle ? (activeVehicle.satRawCOG).toFixed(2) : "N/A"
+                        text:   activeVehicle ? activeVehicle.gps.courseOverGround.valueString : "N/A"
                         color:  colorWhite
                     }
                 }

src/ui/toolbar/MainToolBarIndicators.qml

@@ -176,18 +176,18 @@ Row {
                 smooth:         true
                 width:          mainWindow.tbCellHeight * 0.65
                 height:         mainWindow.tbCellHeight * 0.5
-                opacity:        (activeVehicle && activeVehicle.satelliteCount >= 0) ? 1 : 0.5
+                opacity:        (activeVehicle && activeVehicle.gps.count.value >= 0) ? 1 : 0.5
                 anchors.verticalCenter: parent.verticalCenter
             }
             SignalStrength {
                 size:           mainWindow.tbCellHeight * 0.5
-                percent:        activeVehicle ? getSatStrength(activeVehicle.satRawHDOP) : ""
+                percent:        activeVehicle ? getSatStrength(activeVehicle.gps.hdop.value) : ""
                 anchors.verticalCenter: parent.verticalCenter
             }
         }
         QGCLabel {
-            text:           (activeVehicle && activeVehicle.satelliteCount >= 0) ? activeVehicle.satelliteCount : ""
-            visible:        (activeVehicle && activeVehicle.satelliteCount >= 0)
+            text:           (activeVehicle && activeVehicle.gps.count.value >= 0) ? activeVehicle.gps.count.valueString : ""
+            visible:        (activeVehicle && activeVehicle.gps.count.value >= 0)
             font.pixelSize: tbFontSmall
             color:          colorWhite
             anchors.top:    parent.top