]> git.mxchange.org Git - flightgear.git/blobdiff - src/Instrumentation/gps.cxx
gps warning fix (xxx will be initialized after yyy)
[flightgear.git] / src / Instrumentation / gps.cxx
index 4477dd4eddaf23e5ce1e77b7ad6a0ddfda24694a..1ddb87e083356db9c883a4e360e67c6eca49ec9c 100644 (file)
@@ -74,28 +74,6 @@ SGGeod SGGeodProperty::get() const
     }
 }
 
-static void tieSGGeod(SGPropertyNode* aNode, SGGeod& aRef, 
-  const char* lonStr, const char* latStr, const char* altStr)
-{
-  aNode->tie(lonStr, SGRawValueMethods<SGGeod, double>(aRef, &SGGeod::getLongitudeDeg, &SGGeod::setLongitudeDeg));
-  aNode->tie(latStr, SGRawValueMethods<SGGeod, double>(aRef, &SGGeod::getLatitudeDeg, &SGGeod::setLatitudeDeg));
-  
-  if (altStr) {
-    aNode->tie(altStr, SGRawValueMethods<SGGeod, double>(aRef, &SGGeod::getElevationFt, &SGGeod::setElevationFt));
-  }
-}
-
-static void tieSGGeodReadOnly(SGPropertyNode* aNode, SGGeod& aRef, 
-  const char* lonStr, const char* latStr, const char* altStr)
-{
-  aNode->tie(lonStr, SGRawValueMethods<SGGeod, double>(aRef, &SGGeod::getLongitudeDeg, NULL));
-  aNode->tie(latStr, SGRawValueMethods<SGGeod, double>(aRef, &SGGeod::getLatitudeDeg, NULL));
-  
-  if (altStr) {
-    aNode->tie(altStr, SGRawValueMethods<SGGeod, double>(aRef, &SGGeod::getElevationFt, NULL));
-  }
-}
-
 static const char* makeTTWString(double TTW)
 {
   if ((TTW <= 0.0) || (TTW >= 356400.5)) { // 99 hours
@@ -208,80 +186,34 @@ private:
 GPS::Config::Config() :
   _enableTurnAnticipation(true),
   _turnRate(3.0), // degrees-per-second, so 180 degree turn takes 60 seconds
-  _overflightArmDistance(0.5),
+  _overflightArmDistance(1.0),
   _waypointAlertTime(30.0),
-  _tuneRadio1ToRefVor(false),
   _minRunwayLengthFt(0.0),
   _requireHardSurface(true),
-  _cdiMaxDeflectionNm(-1), // default to angular mode
-  _driveAutopilot(true)
+  _cdiMaxDeflectionNm(3.0), // linear mode, 3nm at the peg
+  _driveAutopilot(true),
+  _courseSelectable(false)
 {
   _enableTurnAnticipation = false;
-  _extCourseSource = fgGetNode("/instrumentation/nav[0]/radials/selected-deg", true);
-}
-
-void GPS::Config::init(SGPropertyNode* aCfgNode)
-{
-  aCfgNode->tie("turn-rate-deg-sec", SGRawValuePointer<double>(&_turnRate));
-  aCfgNode->tie("turn-anticipation", SGRawValuePointer<bool>(&_enableTurnAnticipation));
-  aCfgNode->tie("wpt-alert-time", SGRawValuePointer<double>(&_waypointAlertTime));
-  aCfgNode->tie("tune-nav-radio-to-ref-vor", SGRawValuePointer<bool>(&_tuneRadio1ToRefVor));
-  aCfgNode->tie("min-runway-length-ft", SGRawValuePointer<double>(&_minRunwayLengthFt));
-  aCfgNode->tie("hard-surface-runways-only", SGRawValuePointer<bool>(&_requireHardSurface));
-  
-  aCfgNode->tie("course-source", SGRawValueMethods<GPS::Config, const char*>
-    (*this, &GPS::Config::getCourseSource, &GPS::Config::setCourseSource));
-    
-  aCfgNode->tie("cdi-max-deflection-nm", SGRawValuePointer<double>(&_cdiMaxDeflectionNm));
-  aCfgNode->tie("drive-autopilot", SGRawValuePointer<bool>(&_driveAutopilot));
-}
-
-const char* 
-GPS::Config::getCourseSource() const
-{
-  if (!_extCourseSource) {
-    return "";
-  }
-  
-  return _extCourseSource->getPath(true);
-}
-
-void
-GPS::Config::setCourseSource(const char* aPath)
-{
-  SGPropertyNode* nd = fgGetNode(aPath, false);
-  if (!nd) {
-    SG_LOG(SG_INSTR, SG_WARN, "couldn't find course source at:" << aPath);
-    _extCourseSource = NULL;
-  }
-  
-  _extCourseSource = nd;
 }
 
-double 
-GPS::Config::getExternalCourse() const
+void GPS::Config::bind(GPS* aOwner, SGPropertyNode* aCfg)
 {
-  if (!_extCourseSource) {
-    return 0.0;
-  }
-  
-  return _extCourseSource->getDoubleValue();
+  aOwner->tie(aCfg, "turn-rate-deg-sec", SGRawValuePointer<double>(&_turnRate));
+  aOwner->tie(aCfg, "turn-anticipation", SGRawValuePointer<bool>(&_enableTurnAnticipation));
+  aOwner->tie(aCfg, "wpt-alert-time", SGRawValuePointer<double>(&_waypointAlertTime));
+  aOwner->tie(aCfg, "min-runway-length-ft", SGRawValuePointer<double>(&_minRunwayLengthFt));
+  aOwner->tie(aCfg, "hard-surface-runways-only", SGRawValuePointer<bool>(&_requireHardSurface));
+  aOwner->tie(aCfg, "cdi-max-deflection-nm", SGRawValuePointer<double>(&_cdiMaxDeflectionNm));
+  aOwner->tie(aCfg, "drive-autopilot", SGRawValuePointer<bool>(&_driveAutopilot));
+  aOwner->tie(aCfg, "course-selectable", SGRawValuePointer<bool>(&_courseSelectable));
 }
-      
-void
-GPS::Config::setExternalCourse(double aCourseDeg)
-{
-  if (!_extCourseSource) {
-    return;
-  }
 
-  _extCourseSource->setDoubleValue(aCourseDeg);
-}      
-      
 ////////////////////////////////////////////////////////////////////////////
 
 GPS::GPS ( SGPropertyNode *node) : 
   _selectedCourse(0.0),
+  _desiredCourse(0.0),
   _dataValid(false),
   _lastPosValid(false),
   _mode("init"),
@@ -291,6 +223,9 @@ GPS::GPS ( SGPropertyNode *node) :
   _anticipateTurn(false),
   _inTurn(false)
 {
+  string branch = "/instrumentation/" + _name;
+  _gpsNode = fgGetNode(branch.c_str(), _num, true );
+  _scratchNode = _gpsNode->getChild("scratch", 0, true);
 }
 
 GPS::~GPS ()
@@ -300,112 +235,41 @@ GPS::~GPS ()
 void
 GPS::init ()
 {
-    _routeMgr = (FGRouteMgr*) globals->get_subsystem("route-manager");
-    assert(_routeMgr);
+  _routeMgr = (FGRouteMgr*) globals->get_subsystem("route-manager");
+  assert(_routeMgr);
   
-    string branch;
-    branch = "/instrumentation/" + _name;
-
-  SGPropertyNode *node = fgGetNode(branch.c_str(), _num, true );
-  _config.init(node->getChild("config", 0, true));
-    
   _position.init("/position/longitude-deg", "/position/latitude-deg", "/position/altitude-ft");
   _magvar_node = fgGetNode("/environment/magnetic-variation-deg", true);
-  _serviceable_node = node->getChild("serviceable", 0, true);
+  _serviceable_node = _gpsNode->getChild("serviceable", 0, true);
   _serviceable_node->setBoolValue(true);
   _electrical_node = fgGetNode("/systems/electrical/outputs/gps", true);
 
 // basic GPS outputs
-  node->tie("selected-course-deg", SGRawValueMethods<GPS, double>(*this, &GPS::getSelectedCourse, NULL));
-  
-  _raim_node = node->getChild("raim", 0, true);
-
-  tieSGGeodReadOnly(node, _indicated_pos, "indicated-longitude-deg", 
-        "indicated-latitude-deg", "indicated-altitude-ft");
-
-  node->tie("indicated-vertical-speed", SGRawValueMethods<GPS, double>
-    (*this, &GPS::getVerticalSpeed, NULL));
-  node->tie("indicated-track-true-deg", SGRawValueMethods<GPS, double>
-    (*this, &GPS::getTrueTrack, NULL));
-  node->tie("indicated-track-magnetic-deg", SGRawValueMethods<GPS, double>
-    (*this, &GPS::getMagTrack, NULL));
-  node->tie("indicated-ground-speed-kt", SGRawValueMethods<GPS, double>
-    (*this, &GPS::getGroundspeedKts, NULL));
-        
-  _odometer_node = node->getChild("odometer", 0, true);
-  _trip_odometer_node = node->getChild("trip-odometer", 0, true);
-  _true_bug_error_node = node->getChild("true-bug-error-deg", 0, true);
-  _magnetic_bug_error_node = node->getChild("magnetic-bug-error-deg", 0, true);
-
-// command system    
-  node->tie("mode", SGRawValueMethods<GPS, const char*>(*this, &GPS::getMode, NULL));
-  node->tie("command", SGRawValueMethods<GPS, const char*>(*this, &GPS::getCommand, &GPS::setCommand));
-    
-  _scratchNode = node->getChild("scratch", 0, true);
-  tieSGGeod(_scratchNode, _scratchPos, "longitude-deg", "latitude-deg", "altitude-ft");
-  _scratchNode->tie("valid", SGRawValueMethods<GPS, bool>(*this, &GPS::getScratchValid, NULL));
-  _scratchNode->tie("distance-nm", SGRawValueMethods<GPS, double>(*this, &GPS::getScratchDistance, NULL));
-  _scratchNode->tie("true-bearing-deg", SGRawValueMethods<GPS, double>(*this, &GPS::getScratchTrueBearing, NULL));
-  _scratchNode->tie("mag-bearing-deg", SGRawValueMethods<GPS, double>(*this, &GPS::getScratchMagBearing, NULL));
-  _scratchNode->tie("has-next", SGRawValueMethods<GPS, bool>(*this, &GPS::getScratchHasNext, NULL));
-  _scratchValid = false;
-  
-// waypoint data (including various historical things)
-  SGPropertyNode *wp_node = node->getChild("wp", 0, true);
-  SGPropertyNode *wp0_node = wp_node->getChild("wp", 0, true);
+  _raim_node = _gpsNode->getChild("raim", 0, true);
+  _odometer_node = _gpsNode->getChild("odometer", 0, true);
+  _trip_odometer_node = _gpsNode->getChild("trip-odometer", 0, true);
+  _true_bug_error_node = _gpsNode->getChild("true-bug-error-deg", 0, true);
+  _magnetic_bug_error_node = _gpsNode->getChild("magnetic-bug-error-deg", 0, true);
+  _eastWestVelocity = _gpsNode->getChild("ew-velocity-msec", 0, true);
+  _northSouthVelocity = _gpsNode->getChild("ns-velocity-msec", 0, true);
+  
+// waypoints
+  SGPropertyNode *wp_node = _gpsNode->getChild("wp", 0, true);
   SGPropertyNode *wp1_node = wp_node->getChild("wp", 1, true);
 
-  tieSGGeodReadOnly(wp0_node, _wp0_position, "longitude-deg", "latitude-deg", "altitude-ft");
-  wp0_node->tie("ID", SGRawValueMethods<GPS, const char*>
-    (*this, &GPS::getWP0Ident, NULL));
-  wp0_node->tie("name", SGRawValueMethods<GPS, const char*>
-    (*this, &GPS::getWP0Name, NULL));
-    
-  tieSGGeodReadOnly(wp1_node, _wp1_position, "longitude-deg", "latitude-deg", "altitude-ft");
-  wp1_node->tie("ID", SGRawValueMethods<GPS, const char*>
-    (*this, &GPS::getWP1Ident, NULL));
-  wp1_node->tie("name", SGRawValueMethods<GPS, const char*>
-    (*this, &GPS::getWP1Name, NULL));
-
   // for compatability, alias selected course down to wp/wp[1]/desired-course-deg
   SGPropertyNode* wp1Crs = wp1_node->getChild("desired-course-deg", 0, true);
-  wp1Crs->alias(node->getChild("selected-course-deg"));
+  wp1Crs->alias(_gpsNode->getChild("desired-course-deg", 0, true));
     
 //    _true_wp1_bearing_error_node =
 //        wp1_node->getChild("true-bearing-error-deg", 0, true);
 //    _magnetic_wp1_bearing_error_node =
   //      wp1_node->getChild("magnetic-bearing-error-deg", 0, true);
 
-  wp1_node->tie("distance-nm", SGRawValueMethods<GPS, double>
-    (*this, &GPS::getWP1Distance, NULL));
-  wp1_node->tie("bearing-true-deg", SGRawValueMethods<GPS, double>
-    (*this, &GPS::getWP1Bearing, NULL));
-  wp1_node->tie("bearing-mag-deg", SGRawValueMethods<GPS, double>
-    (*this, &GPS::getWP1MagBearing, NULL));
-  wp1_node->tie("TTW-sec", SGRawValueMethods<GPS, double>
-    (*this, &GPS::getWP1TTW, NULL));
-  wp1_node->tie("TTW", SGRawValueMethods<GPS, const char*>
-    (*this, &GPS::getWP1TTWString, NULL));
-  
-  wp1_node->tie("course-deviation-deg", SGRawValueMethods<GPS, double>
-    (*this, &GPS::getWP1CourseDeviation, NULL));
-  wp1_node->tie("course-error-nm", SGRawValueMethods<GPS, double>
-    (*this, &GPS::getWP1CourseErrorNm, NULL));
-  wp1_node->tie("to-flag", SGRawValueMethods<GPS, bool>
-    (*this, &GPS::getWP1ToFlag, NULL));
-  wp1_node->tie("from-flag", SGRawValueMethods<GPS, bool>
-    (*this, &GPS::getWP1FromFlag, NULL));
-    
-  _tracking_bug_node = node->getChild("tracking-bug", 0, true);
+  _tracking_bug_node = _gpsNode->getChild("tracking-bug", 0, true);
          
-// leg properties (only valid in DTO/LEG modes, not OBS)
-  wp_node->tie("leg-distance-nm", SGRawValueMethods<GPS, double>(*this, &GPS::getLegDistance, NULL));
-  wp_node->tie("leg-true-course-deg", SGRawValueMethods<GPS, double>(*this, &GPS::getLegCourse, NULL));
-  wp_node->tie("leg-mag-course-deg", SGRawValueMethods<GPS, double>(*this, &GPS::getLegMagCourse, NULL));
-  wp_node->tie("alt-dist-ratio", SGRawValueMethods<GPS, double>(*this, &GPS::getAltDistanceRatio, NULL));
-
 // reference navid
-  SGPropertyNode_ptr ref_navaid = node->getChild("ref-navaid", 0, true);
+  SGPropertyNode_ptr ref_navaid = _gpsNode->getChild("ref-navaid", 0, true);
   _ref_navaid_id_node = ref_navaid->getChild("id", 0, true);
   _ref_navaid_name_node = ref_navaid->getChild("name", 0, true);
   _ref_navaid_bearing_node = ref_navaid->getChild("bearing-deg", 0, true);
@@ -417,8 +281,8 @@ GPS::init ()
     
 // route properties    
   // should these move to the route manager?
-  _routeDistanceNm = node->getChild("route-distance-nm", 0, true);
-  _routeETE = node->getChild("ETE", 0, true);
+  _routeDistanceNm = _gpsNode->getChild("route-distance-nm", 0, true);
+  _routeETE = _gpsNode->getChild("ETE", 0, true);
   _routeEditedSignal = fgGetNode("/autopilot/route-manager/signals/edited", true);
   _routeFinishedSignal = fgGetNode("/autopilot/route-manager/signals/finished", true);
   
@@ -433,17 +297,14 @@ GPS::init ()
   _routeFinishedSignal->addChangeListener(_listener);
   
 // navradio slaving properties  
-  node->tie("cdi-deflection", SGRawValueMethods<GPS,double>
-    (*this, &GPS::getCDIDeflection));
-
-  SGPropertyNode* toFlag = node->getChild("to-flag", 0, true);
+  SGPropertyNode* toFlag = _gpsNode->getChild("to-flag", 0, true);
   toFlag->alias(wp1_node->getChild("to-flag"));
   
-  SGPropertyNode* fromFlag = node->getChild("from-flag", 0, true);
+  SGPropertyNode* fromFlag = _gpsNode->getChild("from-flag", 0, true);
   fromFlag->alias(wp1_node->getChild("from-flag"));
     
-        
 // autopilot drive properties
+  _apDrivingFlag = fgGetNode("/autopilot/settings/gps-driving-true-heading", true);
   _apTrueHeading = fgGetNode("/autopilot/settings/true-heading-deg",true);
   _apTargetAltitudeFt = fgGetNode("/autopilot/settings/target-altitude-ft", true);
   _apAltitudeLock = fgGetNode("/autopilot/locks/altitude", true);
@@ -455,11 +316,104 @@ GPS::init ()
   }
   
   // last thing, add the deprecated prop watcher
-  new DeprecatedPropListener(node);
+  new DeprecatedPropListener(_gpsNode);
   
   clearOutput();
 }
 
+void
+GPS::bind()
+{
+  _config.bind(this, _gpsNode->getChild("config", 0, true));
+// basic GPS outputs
+  tie(_gpsNode, "selected-course-deg", SGRawValueMethods<GPS, double>
+    (*this, &GPS::getSelectedCourse, &GPS::setSelectedCourse));
+  
+  tie(_gpsNode, "desired-course-deg", SGRawValueMethods<GPS, double>
+    (*this, &GPS::getDesiredCourse, NULL));
+  _desiredCourseNode = _gpsNode->getChild("desired-course-deg");
+    
+  tieSGGeodReadOnly(_gpsNode, _indicated_pos, "indicated-longitude-deg", 
+        "indicated-latitude-deg", "indicated-altitude-ft");
+
+  tie(_gpsNode, "indicated-vertical-speed", SGRawValueMethods<GPS, double>
+    (*this, &GPS::getVerticalSpeed, NULL));
+  tie(_gpsNode, "indicated-track-true-deg", SGRawValueMethods<GPS, double>
+    (*this, &GPS::getTrueTrack, NULL));
+  tie(_gpsNode, "indicated-track-magnetic-deg", SGRawValueMethods<GPS, double>
+    (*this, &GPS::getMagTrack, NULL));
+  tie(_gpsNode, "indicated-ground-speed-kt", SGRawValueMethods<GPS, double>
+    (*this, &GPS::getGroundspeedKts, NULL));
+  
+// command system    
+  tie(_gpsNode, "mode", SGRawValueMethods<GPS, const char*>(*this, &GPS::getMode, NULL));
+  tie(_gpsNode, "command", SGRawValueMethods<GPS, const char*>(*this, &GPS::getCommand, &GPS::setCommand));
+    
+  tieSGGeod(_scratchNode, _scratchPos, "longitude-deg", "latitude-deg", "altitude-ft");
+  tie(_scratchNode, "valid", SGRawValueMethods<GPS, bool>(*this, &GPS::getScratchValid, NULL));
+  tie(_scratchNode, "distance-nm", SGRawValueMethods<GPS, double>(*this, &GPS::getScratchDistance, NULL));
+  tie(_scratchNode, "true-bearing-deg", SGRawValueMethods<GPS, double>(*this, &GPS::getScratchTrueBearing, NULL));
+  tie(_scratchNode, "mag-bearing-deg", SGRawValueMethods<GPS, double>(*this, &GPS::getScratchMagBearing, NULL));
+  tie(_scratchNode, "has-next", SGRawValueMethods<GPS, bool>(*this, &GPS::getScratchHasNext, NULL));
+  _scratchValid = false;
+  
+// waypoint data (including various historical things)
+  SGPropertyNode *wp_node = _gpsNode->getChild("wp", 0, true);
+  SGPropertyNode *wp0_node = wp_node->getChild("wp", 0, true);
+  SGPropertyNode *wp1_node = wp_node->getChild("wp", 1, true);
+
+  tieSGGeodReadOnly(wp0_node, _wp0_position, "longitude-deg", "latitude-deg", "altitude-ft");
+  tie(wp0_node, "ID", SGRawValueMethods<GPS, const char*>
+    (*this, &GPS::getWP0Ident, NULL));
+  tie(wp0_node, "name", SGRawValueMethods<GPS, const char*>
+    (*this, &GPS::getWP0Name, NULL));
+    
+  tieSGGeodReadOnly(wp1_node, _wp1_position, "longitude-deg", "latitude-deg", "altitude-ft");
+  tie(wp1_node, "ID", SGRawValueMethods<GPS, const char*>
+    (*this, &GPS::getWP1Ident, NULL));
+  tie(wp1_node, "name", SGRawValueMethods<GPS, const char*>
+    (*this, &GPS::getWP1Name, NULL));
+  
+  tie(wp1_node, "distance-nm", SGRawValueMethods<GPS, double>
+    (*this, &GPS::getWP1Distance, NULL));
+  tie(wp1_node, "bearing-true-deg", SGRawValueMethods<GPS, double>
+    (*this, &GPS::getWP1Bearing, NULL));
+  tie(wp1_node, "bearing-mag-deg", SGRawValueMethods<GPS, double>
+    (*this, &GPS::getWP1MagBearing, NULL));
+  tie(wp1_node, "TTW-sec", SGRawValueMethods<GPS, double>
+    (*this, &GPS::getWP1TTW, NULL));
+  tie(wp1_node, "TTW", SGRawValueMethods<GPS, const char*>
+    (*this, &GPS::getWP1TTWString, NULL));
+  
+  tie(wp1_node, "course-deviation-deg", SGRawValueMethods<GPS, double>
+    (*this, &GPS::getWP1CourseDeviation, NULL));
+  tie(wp1_node, "course-error-nm", SGRawValueMethods<GPS, double>
+    (*this, &GPS::getWP1CourseErrorNm, NULL));
+  tie(wp1_node, "to-flag", SGRawValueMethods<GPS, bool>
+    (*this, &GPS::getWP1ToFlag, NULL));
+  tie(wp1_node, "from-flag", SGRawValueMethods<GPS, bool>
+    (*this, &GPS::getWP1FromFlag, NULL));
+
+// leg properties (only valid in DTO/LEG modes, not OBS)
+  tie(wp_node, "leg-distance-nm", SGRawValueMethods<GPS, double>(*this, &GPS::getLegDistance, NULL));
+  tie(wp_node, "leg-true-course-deg", SGRawValueMethods<GPS, double>(*this, &GPS::getLegCourse, NULL));
+  tie(wp_node, "leg-mag-course-deg", SGRawValueMethods<GPS, double>(*this, &GPS::getLegMagCourse, NULL));
+  tie(wp_node, "alt-dist-ratio", SGRawValueMethods<GPS, double>(*this, &GPS::getAltDistanceRatio, NULL));
+
+// navradio slaving properties  
+  tie(_gpsNode, "cdi-deflection", SGRawValueMethods<GPS,double>
+    (*this, &GPS::getCDIDeflection));
+}
+
+void
+GPS::unbind()
+{
+  for (unsigned int t=0; t<_tiedNodes.size(); ++t) {
+    _tiedNodes[t]->untie();
+  }
+  _tiedNodes.clear();
+}
+
 void
 GPS::clearOutput()
 {
@@ -470,6 +424,7 @@ GPS::clearOutput()
   _indicated_pos = SGGeod();
   _last_vertical_speed = 0.0;
   _last_true_track = 0.0;
+  _lastEWVelocity = _lastNSVelocity = 0.0;
   
   _raim_node->setDoubleValue(0.0);
   _indicated_pos = SGGeod();
@@ -481,6 +436,8 @@ GPS::clearOutput()
   _tracking_bug_node->setDoubleValue(0);
   _true_bug_error_node->setDoubleValue(0);
   _magnetic_bug_error_node->setDoubleValue(0);
+  _northSouthVelocity->setDoubleValue(0.0);
+  _eastWestVelocity->setDoubleValue(0.0);
 }
 
 void
@@ -544,9 +501,7 @@ GPS::update (double delta_time_sec)
   updateBasicData(delta_time_sec);
 
   if (_dataValid) {
-    if (_mode == "obs") {
-      _selectedCourse = _config.getExternalCourse();
-    } else {
+    if (_mode != "obs") {
       updateTurn();
     }
       
@@ -560,9 +515,7 @@ GPS::update (double delta_time_sec)
   if (_dataValid && (_mode == "init")) {
     // allow a realistic delay in the future, here
     SG_LOG(SG_INSTR, SG_INFO, "GPS initialisation complete");
-    
-    _selectedCourse = _config.getExternalCourse();
-    
+        
     if (_route_active_node->getBoolValue()) {
       // GPS init with active route
       SG_LOG(SG_INSTR, SG_INFO, "GPS init with active route");
@@ -599,9 +552,28 @@ GPS::updateBasicData(double dt)
   double vertical_speed_mpm = ((_indicated_pos.getElevationM() - _last_pos.getElevationM()) * 60 / dt);
   _last_vertical_speed = vertical_speed_mpm * SG_METER_TO_FEET;
   
-  speed_kt = fgGetLowPass(_last_speed_kts, speed_kt, dt/20.0);
+  speed_kt = fgGetLowPass(_last_speed_kts, speed_kt, dt/10.0);
   _last_speed_kts = speed_kt;
   
+  SGGeod g = _indicated_pos;
+  g.setLongitudeDeg(_last_pos.getLongitudeDeg());
+  double northSouthM = SGGeodesy::distanceM(_last_pos, g);
+  northSouthM = copysign(northSouthM, _indicated_pos.getLatitudeDeg() - _last_pos.getLatitudeDeg());
+  
+  double nsMSec = fgGetLowPass(_lastNSVelocity, northSouthM / dt, dt/2.0);
+  _lastNSVelocity = nsMSec;
+  _northSouthVelocity->setDoubleValue(nsMSec);
+
+
+  g = _indicated_pos;
+  g.setLatitudeDeg(_last_pos.getLatitudeDeg());
+  double eastWestM = SGGeodesy::distanceM(_last_pos, g);
+  eastWestM = copysign(eastWestM, _indicated_pos.getLongitudeDeg() - _last_pos.getLongitudeDeg());
+  
+  double ewMSec = fgGetLowPass(_lastEWVelocity, eastWestM / dt, dt/2.0);
+  _lastEWVelocity = ewMSec;
+  _eastWestVelocity->setDoubleValue(ewMSec);
+  
   double odometer = _odometer_node->getDoubleValue();
   _odometer_node->setDoubleValue(odometer + distance_m * SG_METER_TO_NM);
   odometer = _trip_odometer_node->getDoubleValue();
@@ -660,7 +632,6 @@ void GPS::updateReferenceNavaid(double dt)
         FGNavRecord* vor = (FGNavRecord*) nav.ptr();
         _ref_navaid_frequency_node->setDoubleValue(vor->get_freq() / 100.0);
         _listener->setGuard(false);
-        tuneNavRadios();
       } else {
         // SG_LOG(SG_INSTR, SG_ALERT, "matched existing");
       }
@@ -699,29 +670,12 @@ void GPS::referenceNavaidSet(const std::string& aNavaid)
     _ref_navaid_name_node->setStringValue(_ref_navaid->name().c_str());
     FGNavRecord* vor = (FGNavRecord*) _ref_navaid.ptr();
     _ref_navaid_frequency_node->setDoubleValue(vor->get_freq() / 100.0);
-    tuneNavRadios();
   } else {
     _ref_navaid_set = false;
     _ref_navaid_elapsed = 9999.0; // update next tick
   }
 }
 
-void GPS::tuneNavRadios()
-{
-  if (!_ref_navaid || !_config.tuneNavRadioToRefVor()) {
-    return;
-  }
-  
-  SGPropertyNode_ptr navRadio1 = fgGetNode("/instrumentation/nav", false);
-  if (!navRadio1) {
-    return;
-  }
-  
-  FGNavRecord* vor = (FGNavRecord*) _ref_navaid.ptr();
-  SGPropertyNode_ptr freqs = navRadio1->getChild("frequencies");
-  freqs->setDoubleValue("selected-mhz", vor->get_freq() / 100.0);
-}
-
 void GPS::routeActivated()
 {
   if (_route_active_node->getBoolValue()) {
@@ -768,7 +722,8 @@ void GPS::routeManagerSequenced()
   _wp1Name = wp1.get_name();
   _wp1_position = wp1.get_target();
 
-  _selectedCourse = getLegMagCourse();
+  _desiredCourse = getLegMagCourse();
+  _desiredCourseNode->fireValueChanged();
   wp1Changed();
 }
 
@@ -922,7 +877,7 @@ void GPS::computeTurnData()
     return;
   }
   
-  _turnStartBearing = _selectedCourse;
+  _turnStartBearing = _desiredCourse;
 // compute next leg course
   SGWayPoint wp1(_routeMgr->get_waypoint(curIndex)),
     wp2(_routeMgr->get_waypoint(curIndex + 1));
@@ -1005,26 +960,30 @@ void GPS::updateRouteData()
 void GPS::driveAutopilot()
 {
   if (!_config.driveAutopilot() || !_realismSimpleGps->getBoolValue()) {
+    _apDrivingFlag->setBoolValue(false);
     return;
   }
  
-  // FIXME: we want to set desired track, not heading, here
-  _apTrueHeading->setDoubleValue(getWP1Bearing());
+  // compatability feature - allow the route-manager / GPS to drive the
+  // generic autopilot heading hold *in leg mode only* 
+  
+  bool drive = _mode == "leg";
+  _apDrivingFlag->setBoolValue(drive);
+  
+  if (drive) {
+    // FIXME: we want to set desired track, not heading, here
+    _apTrueHeading->setDoubleValue(getWP1Bearing());
+  }
 }
 
 void GPS::wp1Changed()
 {
-  // update external HSI/CDI/NavDisplay/PFD/etc
-  _config.setExternalCourse(getLegMagCourse());
-
   if (!_config.driveAutopilot()) {
     return;
   }
   
   double altFt = _wp1_position.getElevationFt();
-  if (altFt < -9990.0) {
-    _apTargetAltitudeFt->setDoubleValue(0.0);
-  } else {
+  if (altFt > -9990.0) {
     _apTargetAltitudeFt->setDoubleValue(altFt);
   }
 }
@@ -1032,6 +991,19 @@ void GPS::wp1Changed()
 /////////////////////////////////////////////////////////////////////////////
 // property getter/setters
 
+void GPS::setSelectedCourse(double crs)
+{
+  if (_selectedCourse == crs) {
+    return;
+  }
+  
+  _selectedCourse = crs;
+  if ((_mode == "obs") || _config.courseSelectable()) {
+    _desiredCourse = _selectedCourse;
+    _desiredCourseNode->fireValueChanged();
+  }
+}
+
 double GPS::getLegDistance() const
 {
   if (!_dataValid || (_mode == "obs")) {
@@ -1189,7 +1161,9 @@ double GPS::getWP1MagBearing() const
     return -9999.0;
   }
 
-  return _wp1TrueBearing - _magvar_node->getDoubleValue();
+  double magBearing = _wp1TrueBearing - _magvar_node->getDoubleValue();
+  SG_NORMALIZE_RANGE(magBearing, 0.0, 360.0);
+  return magBearing;
 }
 
 double GPS::getWP1CourseDeviation() const
@@ -1198,7 +1172,7 @@ double GPS::getWP1CourseDeviation() const
     return 0.0;
   }
   
-  double dev = getWP1MagBearing() - _selectedCourse;
+  double dev = getWP1MagBearing() - _desiredCourse;
   SG_NORMALIZE_RANGE(dev, -180.0, 180.0);
   
   if (fabs(dev) > 90.0) {
@@ -1228,7 +1202,7 @@ bool GPS::getWP1ToFlag() const
     return false;
   }
   
-  double dev = getWP1MagBearing() - _selectedCourse;
+  double dev = getWP1MagBearing() - _desiredCourse;
   SG_NORMALIZE_RANGE(dev, -180.0, 180.0);
 
   return (fabs(dev) < 90.0);
@@ -1358,20 +1332,18 @@ bool GPS::isScratchPositionValid() const
 
 void GPS::directTo()
 {
-  if (!isScratchPositionValid()) {
-    SG_LOG(SG_INSTR, SG_WARN, "invalid DTO lat/lon");
-    return;
+  _wp0_position = _indicated_pos;
+  
+  if (isScratchPositionValid()) {
+    _wp1Ident = _scratchNode->getStringValue("ident");
+    _wp1Name = _scratchNode->getStringValue("name");
+    _wp1_position = _scratchPos;
   }
   
-  _wp0_position = _indicated_pos;
-  _wp1Ident = _scratchNode->getStringValue("ident");
-  _wp1Name = _scratchNode->getStringValue("name");
-  _wp1_position = _scratchPos;
-
   _mode = "dto";
-  _selectedCourse = getLegMagCourse();
+  _desiredCourse = getLegMagCourse();
+  _desiredCourseNode->fireValueChanged();
   clearScratch();
-  
   wp1Changed();
 }
 
@@ -1386,7 +1358,7 @@ void GPS::loadRouteWaypoint()
   int index = _scratchNode->getIntValue("index", -9999);
   clearScratch();
   
-  if (index == -9999) { // no index supplied, use current wp
+  if ((index < 0) || (index >= _routeMgr->size())) { // no index supplied, use current wp
     index = _routeMgr->currentWaypoint();
   }
   
@@ -1428,10 +1400,15 @@ void GPS::loadNearest()
   int limitCount = _scratchNode->getIntValue("max-results", 1);
   double cutoffDistance = _scratchNode->getDoubleValue("cutoff-nm", 400.0);
   
-  clearScratch(); // clear now, regardless of whether we find a match or not
+  SGGeod searchPos = _indicated_pos;
+  if (isScratchPositionValid()) {
+    searchPos = _scratchPos;
+  }
   
+  clearScratch(); // clear now, regardless of whether we find a match or not
+    
   _searchResults = 
-    FGPositioned::findClosestN(_indicated_pos, limitCount, cutoffDistance, f.get());
+    FGPositioned::findClosestN(searchPos, limitCount, cutoffDistance, f.get());
   _searchResultsCached = true;
   _searchResultIndex = 0;
   _searchIsRoute = false;
@@ -1636,17 +1613,14 @@ void GPS::addAirportToScratch(FGAirport* aAirport)
 
 void GPS::selectOBSMode()
 {
-  if (!isScratchPositionValid()) {
-    SG_LOG(SG_INSTR, SG_WARN, "invalid OBS lat/lon");
-    return;
+  if (isScratchPositionValid()) {
+    _wp1Ident = _scratchNode->getStringValue("ident");
+    _wp1Name = _scratchNode->getStringValue("name");
+    _wp1_position = _scratchPos;
   }
   
   SG_LOG(SG_INSTR, SG_INFO, "GPS switching to OBS mode");
   _mode = "obs";
-  
-  _wp1Ident = _scratchNode->getStringValue("ident");
-  _wp1Name = _scratchNode->getStringValue("name");
-  _wp1_position = _scratchPos;
   _wp0_position = _indicated_pos;
   wp1Changed();
 }
@@ -1763,4 +1737,26 @@ void GPS::removeWaypointAtIndex(int aIndex)
   _routeMgr->pop_waypoint(aIndex);
 }
 
+void GPS::tieSGGeod(SGPropertyNode* aNode, SGGeod& aRef, 
+  const char* lonStr, const char* latStr, const char* altStr)
+{
+  tie(aNode, lonStr, SGRawValueMethods<SGGeod, double>(aRef, &SGGeod::getLongitudeDeg, &SGGeod::setLongitudeDeg));
+  tie(aNode, latStr, SGRawValueMethods<SGGeod, double>(aRef, &SGGeod::getLatitudeDeg, &SGGeod::setLatitudeDeg));
+  
+  if (altStr) {
+    tie(aNode, altStr, SGRawValueMethods<SGGeod, double>(aRef, &SGGeod::getElevationFt, &SGGeod::setElevationFt));
+  }
+}
+
+void GPS::tieSGGeodReadOnly(SGPropertyNode* aNode, SGGeod& aRef, 
+  const char* lonStr, const char* latStr, const char* altStr)
+{
+  tie(aNode, lonStr, SGRawValueMethods<SGGeod, double>(aRef, &SGGeod::getLongitudeDeg, NULL));
+  tie(aNode, latStr, SGRawValueMethods<SGGeod, double>(aRef, &SGGeod::getLatitudeDeg, NULL));
+  
+  if (altStr) {
+    tie(aNode, altStr, SGRawValueMethods<SGGeod, double>(aRef, &SGGeod::getElevationFt, NULL));
+  }
+}
+
 // end of gps.cxx