Model relative property tree root binding.

Change fgcommand to take an optional property tree root element.

This fixes the animation bindings to use the defined property tree root - to support multiplayer (or other) model that can bind to the correct part of the property tree.

Requires a corresponding fix in sg to allow the command methods to take an optional root parameter.

What this means is that when inside someone else's multiplayer model (e.g. backseat, or co-pilot), the multipalyer (AI) model will correctly modify properties inside the correct part of the property tree inside (/ai), rather than modifying the properties inside the same part of the tree as the non-ai model.

This means that a properly setup model will operate within it's own space in the property tree; and permit more generic multiplayer code to be written.

This is probably responsible for some of the pollution of the root property tree with MP aircraft properties.

src/AIModel/AIManager.cxx

@@ -339,7 +339,7 @@ FGAIManager::processThermal( double dt, FGAIThermal* thermal ) {
 
 }
 
-bool FGAIManager::loadScenarioCommand(const SGPropertyNode* args)
+bool FGAIManager::loadScenarioCommand(const SGPropertyNode* args, SGPropertyNode *)
 {
     std::string name = args->getStringValue("name");
     if (args->hasChild("load-property")) {
@@ -370,9 +370,9 @@ bool FGAIManager::loadScenarioCommand(const SGPropertyNode* args)
     return ok;
 }
 
-bool FGAIManager::unloadScenarioCommand(const SGPropertyNode* args)
+bool FGAIManager::unloadScenarioCommand(const SGPropertyNode * arg, SGPropertyNode * root)
 {
-    std::string name = args->getStringValue("name");
+    std::string name = arg->getStringValue("name");
     return unloadScenario(name);
 }
 

src/AIModel/AIManager.hxx

@@ -97,8 +97,8 @@ private:
     
     void removeDeadItem(FGAIBase* base);
 
-    bool loadScenarioCommand(const SGPropertyNode* args);
+    bool loadScenarioCommand(const SGPropertyNode* args, SGPropertyNode* root);
-    bool unloadScenarioCommand(const SGPropertyNode* args);
+    bool unloadScenarioCommand(const SGPropertyNode* args, SGPropertyNode* root);
     bool addObjectCommand(const SGPropertyNode* definition);
     
     bool removeObject(const SGPropertyNode* args);

src/ATC/atcdialog.cxx

@@ -167,13 +167,13 @@ void FGATCDialogNew::frequencyDisplay(const std::string& ident)
     _gui->showDialog(dialog_name);
 }
 
-static bool doFrequencySearch( const SGPropertyNode* )
+static bool doFrequencySearch( const SGPropertyNode*, SGPropertyNode * )
 {
     FGATCDialogNew::instance()->frequencySearch();
     return true;
 }
 
-static bool doFrequencyDisplay( const SGPropertyNode* args )
+static bool doFrequencyDisplay( const SGPropertyNode* args, SGPropertyNode * root)
 {
     std::string icao = args->getStringValue("icao");
     if (icao.empty()) {

src/ATC/atcdialog.hxx

@@ -58,7 +58,7 @@ public:
     void addEntry(int, const std::string&);
     void removeEntry(int);
 
-    static bool popup( const SGPropertyNode * ) {
+    static bool popup( const SGPropertyNode *, SGPropertyNode * root) {
         instance()->PopupDialog();
         return true;
     }

src/Autopilot/digitalfilter.cxx

@@ -589,23 +589,50 @@ void HighPassFilterImplementation::initialize( double initvalue )
   _output_1 = initvalue;
 }
 
-double HighPassFilterImplementation::compute(  double dt, double input )
+//double HighPassFilterImplementation::compute(  double dt, double input )
+//{
+//  input = GainFilterImplementation::compute( dt, input );
+//  double tf = _TfInput.get_value();
+//
+//  double output;
+//
+//  // avoid negative filter times
+//  // and div by zero if -tf == dt
+//
+//  double alpha = tf > 0.0 ? 1 / ((tf/dt) + 1) : 1.0;
+//  output = (1 - alpha) * (input - _input_1 +  _output_1);
+//  _input_1 = input;
+//  _output_1 = output;
+//  return output;
+//}
+
+double HighPassFilterImplementation::compute(double dt, double input)
 {
-  input = GainFilterImplementation::compute( dt, input );
+    if (_isnan(input))
-  double tf = _TfInput.get_value();
+        SG_LOG(SG_AUTOPILOT, SG_ALERT, "High pass filter output is NaN.");
 
-  double output;
+    input = GainFilterImplementation::compute(dt, input);
+    double tf = _TfInput.get_value();
 
-  // avoid negative filter times
+    double output;
-  // and div by zero if -tf == dt
 
-  double alpha = tf > 0.0 ? 1 / ((tf/dt) + 1) : 1.0;
+    // avoid negative filter times
-  output = (1 - alpha) * (input - _input_1 +  _output_1);
+    // and div by zero if -tf == dt
-  _input_1 = input;
+
-  _output_1 = output;
+
-  return output;
+    double alpha = tf > 0.0 ? 1 / ((tf / dt) + 1) : 1.0;
+    output = (1 - alpha) * (input - _input_1 + _output_1);
+    _input_1 = input;
+
+    // Catch NaN before it causes damage
+
+    if (output != output) {
+        SG_LOG(SG_AUTOPILOT, SG_ALERT, "High pass filter output is NaN.");
+        output = 0.0;
+    }
+    _output_1 = output;
+    return output;
 }
-
 //------------------------------------------------------------------------------
 bool HighPassFilterImplementation::configure( SGPropertyNode& cfg_node,
                                               const std::string& cfg_name,
@@ -803,6 +830,8 @@ void DigitalFilter::update( bool firstTime, double dt)
   }
 
   double input = _valueInput.get_value() - _referenceInput.get_value();
+  if (_isnan(input))
+      input = _valueInput.get_value() - _referenceInput.get_value();
   double output = _implementation->compute( dt, input );
 
   set_output_value( output );

src/Autopilot/inputvalue.cxx

@@ -205,7 +205,8 @@ double InputValue::get_value() const
     if( _periodical ) {
       value = _periodical->normalize( value );
     }
-    
+    if (_isnan(value))
+        SG_LOG(SG_AUTOPILOT, SG_ALERT, "input is NaN." );
     return _abs ? fabs(value) : value;
 }
 

src/Autopilot/route_mgr.cxx

@@ -63,14 +63,14 @@
 using namespace flightgear;
 using std::string;
 
-static bool commandLoadFlightPlan(const SGPropertyNode* arg)
+static bool commandLoadFlightPlan(const SGPropertyNode* arg, SGPropertyNode *)
 {
   FGRouteMgr* self = (FGRouteMgr*) globals->get_subsystem("route-manager");
   SGPath path = SGPath::fromUtf8(arg->getStringValue("path"));
   return self->loadRoute(path);
 }
 
-static bool commandSaveFlightPlan(const SGPropertyNode* arg)
+static bool commandSaveFlightPlan(const SGPropertyNode* arg, SGPropertyNode *)
 {
   FGRouteMgr* self = (FGRouteMgr*) globals->get_subsystem("route-manager");
   SGPath path = SGPath::fromUtf8(arg->getStringValue("path"));
@@ -92,7 +92,7 @@ static bool commandSaveFlightPlan(const SGPropertyNode* arg)
   }
 }
 
-static bool commandActivateFlightPlan(const SGPropertyNode* arg)
+static bool commandActivateFlightPlan(const SGPropertyNode* arg, SGPropertyNode *)
 {
   FGRouteMgr* self = (FGRouteMgr*) globals->get_subsystem("route-manager");
   bool activate = arg->getBoolValue("activate", true);
@@ -105,14 +105,14 @@ static bool commandActivateFlightPlan(const SGPropertyNode* arg)
   return true;
 }
 
-static bool commandClearFlightPlan(const SGPropertyNode*)
+static bool commandClearFlightPlan(const SGPropertyNode*, SGPropertyNode *)
 {
   FGRouteMgr* self = (FGRouteMgr*) globals->get_subsystem("route-manager");
   self->clearRoute();
   return true;
 }
 
-static bool commandSetActiveWaypt(const SGPropertyNode* arg)
+static bool commandSetActiveWaypt(const SGPropertyNode* arg, SGPropertyNode *)
 {
   FGRouteMgr* self = (FGRouteMgr*) globals->get_subsystem("route-manager");
   int index = arg->getIntValue("index");
@@ -124,7 +124,7 @@ static bool commandSetActiveWaypt(const SGPropertyNode* arg)
   return true;
 }
 
-static bool commandInsertWaypt(const SGPropertyNode* arg)
+static bool commandInsertWaypt(const SGPropertyNode* arg, SGPropertyNode *)
 {
   FGRouteMgr* self = (FGRouteMgr*) globals->get_subsystem("route-manager");
   int index = arg->getIntValue("index");
@@ -213,7 +213,7 @@ static bool commandInsertWaypt(const SGPropertyNode* arg)
   return true;
 }
 
-static bool commandDeleteWaypt(const SGPropertyNode* arg)
+static bool commandDeleteWaypt(const SGPropertyNode* arg, SGPropertyNode *)
 {
   FGRouteMgr* self = (FGRouteMgr*) globals->get_subsystem("route-manager");
   int index = arg->getIntValue("index");
@@ -1187,7 +1187,7 @@ SGPropertyNode_ptr FGRouteMgr::wayptNodeAtIndex(int index) const
   return mirror->getChild("wp", index);
 }
 
-bool FGRouteMgr::commandDefineUserWaypoint(const SGPropertyNode* arg)
+bool FGRouteMgr::commandDefineUserWaypoint(const SGPropertyNode * arg, SGPropertyNode * root)
 {
     std::string ident = arg->getStringValue("ident");
     if (ident.empty()) {
@@ -1209,7 +1209,7 @@ bool FGRouteMgr::commandDefineUserWaypoint(const SGPropertyNode* arg)
     return true;
 }
 
-bool FGRouteMgr::commandDeleteUserWaypoint(const SGPropertyNode* arg)
+bool FGRouteMgr::commandDeleteUserWaypoint(const SGPropertyNode * arg, SGPropertyNode * root)
 {
     std::string ident = arg->getStringValue("ident");
     if (ident.empty()) {

src/Autopilot/route_mgr.hxx

@@ -102,8 +102,8 @@ public:
 
   static const char* subsystemName() { return "route-manager"; }
 private:
-    bool commandDefineUserWaypoint(const SGPropertyNode* arg);
+    bool commandDefineUserWaypoint(const SGPropertyNode * arg, SGPropertyNode * root);
-    bool commandDeleteUserWaypoint(const SGPropertyNode* arg);
+    bool commandDeleteUserWaypoint(const SGPropertyNode * arg, SGPropertyNode * root);
     
     flightgear::FlightPlanRef _plan;
   

src/Environment/fgclouds.cxx

@@ -346,7 +346,7 @@ bool FGClouds::get_3dClouds() const
  * (Various) - cloud definition properties. See README.3DClouds
  *
  */
- bool FGClouds::add3DCloud(const SGPropertyNode *arg)
+ bool FGClouds::add3DCloud(const SGPropertyNode *arg, SGPropertyNode * root)
  {
    int l = arg->getIntValue("layer", 0);
    int index = arg->getIntValue("index", 0);
@@ -381,7 +381,7 @@ bool FGClouds::get_3dClouds() const
   * index - the cloud index
   *
   */
- bool FGClouds::delete3DCloud(const SGPropertyNode *arg)
+ bool FGClouds::delete3DCloud(const SGPropertyNode *arg, SGPropertyNode * root)
  {
    int l = arg->getIntValue("layer", 0);
    int i = arg->getIntValue("index", 0);
@@ -400,7 +400,7 @@ bool FGClouds::get_3dClouds() const
  * lon/lat/alt - the position for the cloud
  *
  */
-bool FGClouds::move3DCloud(const SGPropertyNode *arg)
+bool FGClouds::move3DCloud(const SGPropertyNode *arg, SGPropertyNode * root)
  {
    int l = arg->getIntValue("layer", 0);
    int i = arg->getIntValue("index", 0);

src/Environment/fgclouds.hxx

@@ -42,9 +42,9 @@ private:
 	bool clouds_3d_enabled;
     int index;
   
-    bool add3DCloud(const SGPropertyNode *arg);
+    bool add3DCloud(const SGPropertyNode *arg, SGPropertyNode * root);
-    bool delete3DCloud(const SGPropertyNode *arg);
+    bool delete3DCloud(const SGPropertyNode *arg, SGPropertyNode * root);
-    bool move3DCloud(const SGPropertyNode *arg);
+    bool move3DCloud(const SGPropertyNode *arg, SGPropertyNode * root);
     
 public:
 	FGClouds();

src/Environment/realwx_ctrl.cxx

@@ -193,7 +193,7 @@ protected:
 
 };
 
-static bool commandRequestMetar(const SGPropertyNode* arg)
+static bool commandRequestMetar(const SGPropertyNode * arg, SGPropertyNode * root)
 {
   SGSubsystemGroup* envMgr = (SGSubsystemGroup*) globals->get_subsystem("environment");
   if (!envMgr) {
@@ -212,7 +212,7 @@ static bool commandRequestMetar(const SGPropertyNode* arg)
   return true;
 }
   
-static bool commandClearMetar(const SGPropertyNode* arg)
+static bool commandClearMetar(const SGPropertyNode * arg, SGPropertyNode * root)
 {
   SGSubsystemGroup* envMgr = (SGSubsystemGroup*) globals->get_subsystem("environment");
   if (!envMgr) {

src/GUI/FGPUIMenuBar.cxx

@@ -33,7 +33,7 @@ using std::map;
 #if defined(TR_HIRES_SNAP)
 extern void dumpHiResSnapShot ();
 static bool
-do_hires_snapshot_dialog (const SGPropertyNode * arg)
+do_hires_snapshot_dialog (const SGPropertyNode * arg, SGPropertyNode * root)
 {
     dumpHiResSnapShot();
     return true;

src/GUI/MessageBox.cxx

@@ -117,7 +117,7 @@ MessageBoxResult modalMessageBox(const std::string& caption,
         args->setStringValue("caption", caption);
         args->setStringValue("message", msg);
         args->setStringValue("more", moreText);
-        globals->get_commands()->execute("canvas-message-box", args);
+        globals->get_commands()->execute("canvas-message-box", args, nullptr);
 
         // how to make it modal?
 

src/GUI/MouseCursor.cxx

@@ -194,7 +194,7 @@ void FGMouseCursor::setAutoHideTimeMsec(unsigned int aMsec)
 }
 
 
-bool FGMouseCursor::setCursorCommand(const SGPropertyNode* arg)
+bool FGMouseCursor::setCursorCommand(const SGPropertyNode* arg, SGPropertyNode*)
 {
     // JMT 2013 - I would prefer this was a seperate 'warp' command, but
     // historically set-cursor has done both. 

src/GUI/MouseCursor.hxx

@@ -57,7 +57,7 @@ public:
 protected:
     FGMouseCursor();
     
-    bool setCursorCommand(const SGPropertyNode* arg);
+    bool setCursorCommand(const SGPropertyNode* arg, SGPropertyNode*);
     
     unsigned int mAutoHideTimeMsec;
 };

src/GUI/gui.cxx

@@ -197,9 +197,9 @@ void syncPausePopupState()
     args->setStringValue("id", "sim-pause");
     if (paused && fgGetBool("/sim/view-name-popup")) {
       args->setStringValue("label", "Simulation is paused");
-      globals->get_commands()->execute("show-message", args);
+      globals->get_commands()->execute("show-message", args, nullptr);
     } else {
-      globals->get_commands()->execute("clear-message", args);
+      globals->get_commands()->execute("clear-message", args, nullptr);
     }
 
 }

src/Input/FGJoystickInput.cxx

@@ -214,7 +214,7 @@ void FGJoystickInput::postinit()
     unsigned int j;
     for (j = 0; j < nasal.size(); j++) {
       nasal[j]->setStringValue("module", module.c_str());
-      nasalsys->handleCommand(nasal[j]);
+      nasalsys->handleCommand(nasal[j],nullptr);
     }
 
     //

src/Input/FGKeyboardInput.cxx

@@ -112,7 +112,7 @@ void FGKeyboardInput::postinit()
   PropertyList nasal = key_nodes->getChildren("nasal");
   for (unsigned int j = 0; j < nasal.size(); j++) {
     nasal[j]->setStringValue("module", module.c_str());
-    nasalsys->handleCommand(nasal[j]);
+    nasalsys->handleCommand(nasal[j], nullptr);
   }
 
   PropertyList keys = key_nodes->getChildren("key");

src/Input/FGMouseInput.cxx

@@ -263,7 +263,7 @@ public:
         FGMouseCursor::instance()->setCursor(cur);
         if (!didPick) {
           SGPropertyNode_ptr args(new SGPropertyNode);
-          globals->get_commands()->execute("update-hover", args);
+          globals->get_commands()->execute("update-hover", args, nullptr);
 
         }
     }
@@ -501,7 +501,7 @@ void FGMouseInput::update ( double dt )
   {
       d->tooltipTimeoutDone = true;
       SGPropertyNode_ptr arg(new SGPropertyNode);
-      globals->get_commands()->execute("tooltip-timeout", arg);
+      globals->get_commands()->execute("tooltip-timeout", arg, nullptr);
   }
   
   if ( d->hideCursor ) {
@@ -610,7 +610,7 @@ void FGMouseInput::doMouseClick (int b, int updown, int x, int y, bool mainWindo
       if (d->clickTriggersTooltip) {
             SGPropertyNode_ptr args(new SGPropertyNode);
             args->setStringValue("reason", "click");
-            globals->get_commands()->execute("tooltip-timeout", args);
+            globals->get_commands()->execute("tooltip-timeout", args, nullptr);
             d->tooltipTimeoutDone = true;
       }
     } else {

src/Instrumentation/KLN89/kln89.cxx

@@ -55,76 +55,76 @@ using std::string;
 
 // Command callbacks for FlightGear
 
-static bool do_kln89_msg_pressed(const SGPropertyNode* arg) {
+static bool do_kln89_msg_pressed(const SGPropertyNode * arg, SGPropertyNode * root) {
 	//cout << "do_kln89_msg_pressed called!\n";
 	KLN89* gps = (KLN89*)globals->get_subsystem("kln89");
 	gps->MsgPressed();
 	return(true);
 }
 
-static bool do_kln89_obs_pressed(const SGPropertyNode* arg) {
+static bool do_kln89_obs_pressed(const SGPropertyNode * arg, SGPropertyNode * root) {
 	//cout << "do_kln89_obs_pressed called!\n";
 	KLN89* gps = (KLN89*)globals->get_subsystem("kln89");
 	gps->OBSPressed();
 	return(true);
 }
 
-static bool do_kln89_alt_pressed(const SGPropertyNode* arg) {
+static bool do_kln89_alt_pressed(const SGPropertyNode * arg, SGPropertyNode * root) {
 	//cout << "do_kln89_alt_pressed called!\n";
 	KLN89* gps = (KLN89*)globals->get_subsystem("kln89");
 	gps->AltPressed();
 	return(true);
 }
 
-static bool do_kln89_nrst_pressed(const SGPropertyNode* arg) {
+static bool do_kln89_nrst_pressed(const SGPropertyNode * arg, SGPropertyNode * root) {
 	KLN89* gps = (KLN89*)globals->get_subsystem("kln89");
 	gps->NrstPressed();
 	return(true);
 }
 
-static bool do_kln89_dto_pressed(const SGPropertyNode* arg) {
+static bool do_kln89_dto_pressed(const SGPropertyNode * arg, SGPropertyNode * root) {
 	KLN89* gps = (KLN89*)globals->get_subsystem("kln89");
 	gps->DtoPressed();
 	return(true);
 }
 
-static bool do_kln89_clr_pressed(const SGPropertyNode* arg) {
+static bool do_kln89_clr_pressed(const SGPropertyNode * arg, SGPropertyNode * root) {
 	KLN89* gps = (KLN89*)globals->get_subsystem("kln89");
 	gps->ClrPressed();
 	return(true);
 }
 
-static bool do_kln89_ent_pressed(const SGPropertyNode* arg) {
+static bool do_kln89_ent_pressed(const SGPropertyNode * arg, SGPropertyNode * root) {
 	KLN89* gps = (KLN89*)globals->get_subsystem("kln89");
 	gps->EntPressed();
 	return(true);
 }
 
-static bool do_kln89_crsr_pressed(const SGPropertyNode* arg) {
+static bool do_kln89_crsr_pressed(const SGPropertyNode * arg, SGPropertyNode * root) {
 	KLN89* gps = (KLN89*)globals->get_subsystem("kln89");
 	gps->CrsrPressed();
 	return(true);
 }
 
-static bool do_kln89_knob1left1(const SGPropertyNode* arg) {
+static bool do_kln89_knob1left1(const SGPropertyNode * arg, SGPropertyNode * root) {
 	KLN89* gps = (KLN89*)globals->get_subsystem("kln89");
 	gps->Knob1Left1();
 	return(true);
 }
 
-static bool do_kln89_knob1right1(const SGPropertyNode* arg) {
+static bool do_kln89_knob1right1(const SGPropertyNode * arg, SGPropertyNode * root) {
 	KLN89* gps = (KLN89*)globals->get_subsystem("kln89");
 	gps->Knob1Right1();
 	return(true);
 }
 
-static bool do_kln89_knob2left1(const SGPropertyNode* arg) {
+static bool do_kln89_knob2left1(const SGPropertyNode * arg, SGPropertyNode * root) {
 	KLN89* gps = (KLN89*)globals->get_subsystem("kln89");
 	gps->Knob2Left1();
 	return(true);
 }
 
-static bool do_kln89_knob2right1(const SGPropertyNode* arg) {
+static bool do_kln89_knob2right1(const SGPropertyNode * arg, SGPropertyNode * root) {
 	KLN89* gps = (KLN89*)globals->get_subsystem("kln89");
 	gps->Knob2Right1();
 	return(true);

src/Main/fg_commands.cxx

@@ -62,14 +62,36 @@ using std::ofstream;
 
 
 static inline SGPropertyNode *
-get_prop (const SGPropertyNode * arg)
+get_prop (const SGPropertyNode * arg, SGPropertyNode * root)
 {
+    if (root != nullptr)
+    {
+        SGPropertyNode *rv = nullptr;
+        rv = root->getNode(arg->getStringValue("property[0]", "/null"), 0, true);
+        if (rv == nullptr)
+        {
+            rv = root->getNode(arg->getStringValue("property[0]", "/null"), 0, true);
+            return fgGetNode(arg->getStringValue("property[0]", "/null"), true);
+        }
+        return rv;
+    }
     return fgGetNode(arg->getStringValue("property[0]", "/null"), true);
 }
 
 static inline SGPropertyNode *
-get_prop2 (const SGPropertyNode * arg)
+get_prop2 (const SGPropertyNode * arg, SGPropertyNode * root)
 {
+    if (root != nullptr)
+    {
+        SGPropertyNode *rv = nullptr;
+        rv = root->getNode(arg->getStringValue("property[1]", "/null"), 0, true);
+        if (rv == nullptr)
+        {
+            rv = root->getNode(arg->getStringValue("property[1]", "/null"), 0, true);
+            return fgGetNode(arg->getStringValue("property[1]", "/null"), true);
+        }
+        return rv;
+    }
     return fgGetNode(arg->getStringValue("property[1]", "/null"), true);
 }
 
@@ -163,7 +185,7 @@ compare_values (SGPropertyNode * value1, SGPropertyNode * value2)
  * Built-in command: do nothing.
  */
 static bool
-do_null (const SGPropertyNode * arg)
+do_null (const SGPropertyNode * arg, SGPropertyNode * root)
 {
   return true;
 }
@@ -172,16 +194,16 @@ do_null (const SGPropertyNode * arg)
  * Built-in command: run a Nasal script.
  */
 static bool
-do_nasal (const SGPropertyNode * arg)
+do_nasal (const SGPropertyNode * arg, SGPropertyNode * root)
 {
-    return ((FGNasalSys*)globals->get_subsystem("nasal"))->handleCommand(arg);
+    return ((FGNasalSys*)globals->get_subsystem("nasal"))->handleCommand(arg, root);
 }
 
 /**
  * Built-in command: replay the FDR buffer
  */
 static bool
-do_replay (const SGPropertyNode * arg)
+do_replay (const SGPropertyNode * arg, SGPropertyNode * root)
 {
     FGReplay *r = (FGReplay *)(globals->get_subsystem( "replay" ));
     return r->start();
@@ -191,7 +213,7 @@ do_replay (const SGPropertyNode * arg)
  * Built-in command: pause/unpause the sim
  */
 static bool
-do_pause (const SGPropertyNode * arg)
+do_pause (const SGPropertyNode * arg, SGPropertyNode * root)
 {
     bool forcePause = arg->getBoolValue("force-pause", false );
     bool forcePlay = arg->getBoolValue("force-play", false );
@@ -203,7 +225,7 @@ do_pause (const SGPropertyNode * arg)
 
     if (paused && (fgGetInt("/sim/freeze/replay-state",0)>0))
     {
-        do_replay(NULL);
+        do_replay(NULL, nullptr);
     }
     else
     {
@@ -222,7 +244,7 @@ do_pause (const SGPropertyNode * arg)
  *   directory).  Defaults to "fgfs.sav"
  */
 static bool
-do_load (const SGPropertyNode * arg)
+do_load (const SGPropertyNode * arg, SGPropertyNode * root)
 {
     SGPath file(arg->getStringValue("file", "fgfs.sav"));
 
@@ -255,7 +277,7 @@ do_load (const SGPropertyNode * arg)
  * current directory).  Defaults to "fgfs.sav".
  */
 static bool
-do_save (const SGPropertyNode * arg)
+do_save (const SGPropertyNode * arg, SGPropertyNode * root)
 {
     SGPath file(arg->getStringValue("file", "fgfs.sav"));
 
@@ -287,7 +309,7 @@ do_save (const SGPropertyNode * arg)
  *
  */
 static bool
-do_save_tape (const SGPropertyNode * arg)
+do_save_tape (const SGPropertyNode * arg, SGPropertyNode * root)
 {
     FGReplay* replay = (FGReplay*) globals->get_subsystem("replay");
     replay->saveTape(arg);
@@ -299,7 +321,7 @@ do_save_tape (const SGPropertyNode * arg)
  *
  */
 static bool
-do_load_tape (const SGPropertyNode * arg)
+do_load_tape (const SGPropertyNode * arg, SGPropertyNode * root)
 {
     FGReplay* replay = (FGReplay*) globals->get_subsystem("replay");
     replay->loadTape(arg);
@@ -333,7 +355,7 @@ do_view_prev(bool do_it)
  * Built-in command: cycle view.
  */
 static bool
-do_view_cycle (const SGPropertyNode * arg)
+do_view_cycle (const SGPropertyNode * arg, SGPropertyNode * root)
 {
   globals->get_current_view()->setHeadingOffset_deg(0.0);
   globals->get_viewmgr()->next_view();
@@ -346,9 +368,9 @@ do_view_cycle (const SGPropertyNode * arg)
  * property: The name of the property to toggle.
  */
 static bool
-do_property_toggle (const SGPropertyNode * arg)
+do_property_toggle (const SGPropertyNode * arg, SGPropertyNode * root)
 {
-  SGPropertyNode * prop = get_prop(arg);
+  SGPropertyNode * prop = get_prop(arg, root);
   return prop->setBoolValue(!prop->getBoolValue());
 }
 
@@ -361,16 +383,16 @@ do_property_toggle (const SGPropertyNode * arg)
  * property[1]: the property to copy from.
  */
 static bool
-do_property_assign (const SGPropertyNode * arg)
+do_property_assign (const SGPropertyNode * arg, SGPropertyNode * root)
 {
-  SGPropertyNode * prop = get_prop(arg);
+  SGPropertyNode * prop = get_prop(arg,root);
   const SGPropertyNode * value = arg->getNode("value");
 
   if (value != 0)
       return prop->setUnspecifiedValue(value->getStringValue());
   else
   {
-      const SGPropertyNode * prop2 = get_prop2(arg);
+      const SGPropertyNode * prop2 = get_prop2(arg,root);
       if (prop2)
           return prop->setUnspecifiedValue(prop2->getStringValue());
       else
@@ -400,9 +422,9 @@ do_property_assign (const SGPropertyNode * arg)
  *       false).
  */
 static bool
-do_property_adjust (const SGPropertyNode * arg)
+do_property_adjust (const SGPropertyNode * arg, SGPropertyNode * root)
 {
-  SGPropertyNode * prop = get_prop(arg);
+  SGPropertyNode * prop = get_prop(arg,root);
 
   double amount = 0;
   if (arg->hasValue("step"))
@@ -438,9 +460,9 @@ do_property_adjust (const SGPropertyNode * arg)
  *       false).
  */
 static bool
-do_property_multiply (const SGPropertyNode * arg)
+do_property_multiply (const SGPropertyNode * arg, SGPropertyNode * root)
 {
-  SGPropertyNode * prop = get_prop(arg);
+  SGPropertyNode * prop = get_prop(arg,root);
   double factor = arg->getDoubleValue("factor", 1);
 
   double unmodifiable, modifiable;
@@ -462,10 +484,10 @@ do_property_multiply (const SGPropertyNode * arg)
  * property[1]: the name of the second property.
  */
 static bool
-do_property_swap (const SGPropertyNode * arg)
+do_property_swap (const SGPropertyNode * arg, SGPropertyNode * root)
 {
-  SGPropertyNode * prop1 = get_prop(arg);
+  SGPropertyNode * prop1 = get_prop(arg,root);
-  SGPropertyNode * prop2 = get_prop2(arg);
+  SGPropertyNode * prop2 = get_prop2(arg,root);
 
 				// FIXME: inefficient
   const string & tmp = prop1->getStringValue();
@@ -483,9 +505,9 @@ do_property_swap (const SGPropertyNode * arg)
  * factor: the factor to multiply by (use negative to reverse).
  */
 static bool
-do_property_scale (const SGPropertyNode * arg)
+do_property_scale (const SGPropertyNode * arg, SGPropertyNode * root)
 {
-  SGPropertyNode * prop = get_prop(arg);
+  SGPropertyNode * prop = get_prop(arg,root);
   double setting = arg->getDoubleValue("setting");
   double offset = arg->getDoubleValue("offset", 0.0);
   double factor = arg->getDoubleValue("factor", 1.0);
@@ -527,9 +549,9 @@ do_property_scale (const SGPropertyNode * arg)
  * value[*]: the list of values to cycle through.
  */
 static bool
-do_property_cycle (const SGPropertyNode * arg)
+do_property_cycle (const SGPropertyNode * arg, SGPropertyNode * root)
 {
-    SGPropertyNode * prop = get_prop(arg);
+    SGPropertyNode * prop = get_prop(arg,root);
     std::vector<SGPropertyNode_ptr> values = arg->getChildren("value");
 
     bool wrap = arg->getBoolValue("wrap", true);
@@ -576,9 +598,9 @@ do_property_cycle (const SGPropertyNode * arg)
  * max: the maximum allowed value.
  */
 static bool
-do_property_randomize (const SGPropertyNode * arg)
+do_property_randomize (const SGPropertyNode * arg, SGPropertyNode * root)
 {
-    SGPropertyNode * prop = get_prop(arg);
+    SGPropertyNode * prop = get_prop(arg,root);
     double min = arg->getDoubleValue("min", DBL_MIN);
     double max = arg->getDoubleValue("max", DBL_MAX);
     prop->setDoubleValue(sg_random() * (max - min) + min);
@@ -604,9 +626,9 @@ do_property_randomize (const SGPropertyNode * arg)
  *                  the property value at the given speed.
  */
 static bool
-do_property_interpolate (const SGPropertyNode * arg)
+do_property_interpolate (const SGPropertyNode * arg, SGPropertyNode * root)
 {
-  SGPropertyNode * prop = get_prop(arg);
+  SGPropertyNode * prop = get_prop(arg,root);
   if( !prop )
     return false;
 
@@ -675,7 +697,7 @@ do_property_interpolate (const SGPropertyNode * arg)
  * current contents of the /logger tree.
  */
 static bool
-do_data_logging_commit (const SGPropertyNode * arg)
+do_data_logging_commit (const SGPropertyNode * arg, SGPropertyNode * root)
 {
     FGLogger *log = (FGLogger *)globals->get_subsystem("logger");
     log->reinit();
@@ -686,7 +708,7 @@ do_data_logging_commit (const SGPropertyNode * arg)
  * Built-in command: set log level (0 ... 7)
  */
 static bool
-do_log_level (const SGPropertyNode * arg)
+do_log_level (const SGPropertyNode * arg, SGPropertyNode * root)
 {
    sglog().setLogLevels( SG_ALL, (sgDebugPriority)arg->getIntValue() );
 
@@ -706,7 +728,7 @@ do_log_level (const SGPropertyNode * arg)
  */
 
 static bool
-do_load_xml_to_proptree(const SGPropertyNode * arg)
+do_load_xml_to_proptree(const SGPropertyNode * arg, SGPropertyNode * root)
 {
     SGPath file(arg->getStringValue("filename"));
     if (file.isNull())
@@ -760,7 +782,7 @@ do_load_xml_to_proptree(const SGPropertyNode * arg)
 }
 
 static bool
-do_load_xml_from_url(const SGPropertyNode * arg)
+do_load_xml_from_url(const SGPropertyNode * arg, SGPropertyNode * root)
 {
     FGHTTPClient* http = static_cast<FGHTTPClient*>(globals->get_subsystem("http"));
     if (!http) {
@@ -810,7 +832,7 @@ do_load_xml_from_url(const SGPropertyNode * arg)
  */
 
 static bool
-do_save_xml_from_proptree(const SGPropertyNode * arg)
+do_save_xml_from_proptree(const SGPropertyNode * arg, SGPropertyNode * root)
 {
     SGPath file(arg->getStringValue("filename"));
     if (file.isNull())
@@ -861,7 +883,7 @@ no_profiling_support()
 #endif
 
 static bool
-do_profiler_start(const SGPropertyNode *arg)
+do_profiler_start(const SGPropertyNode *arg, SGPropertyNode *root)
 {
 #if FG_HAVE_GPERFTOOLS
   const char *filename = arg->getStringValue("filename", "fgfs.profile");
@@ -874,7 +896,7 @@ do_profiler_start(const SGPropertyNode *arg)
 }
 
 static bool
-do_profiler_stop(const SGPropertyNode *arg)
+do_profiler_stop(const SGPropertyNode *arg, SGPropertyNode *root)
 {
 #if FG_HAVE_GPERFTOOLS
   ProfilerStop();

src/Main/fg_scene_commands.cxx

@@ -71,7 +71,7 @@
  * status: the exit status to return to the operating system (defaults to 0)
  */
 static bool
-do_exit (const SGPropertyNode * arg)
+do_exit (const SGPropertyNode * arg, SGPropertyNode * root)
 {
     SG_LOG(SG_INPUT, SG_INFO, "Program exit requested.");
     fgSetBool("/sim/signals/exit", true);
@@ -85,7 +85,7 @@ do_exit (const SGPropertyNode * arg)
  * Reset FlightGear (Shift-Escape or Menu->File->Reset)
  */
 static bool
-do_reset (const SGPropertyNode * arg)
+do_reset (const SGPropertyNode * arg, SGPropertyNode * root)
 {
     fgResetIdleState();
     return true;
@@ -96,7 +96,7 @@ do_reset (const SGPropertyNode * arg)
  * Change aircraft
  */
 static bool
-do_switch_aircraft (const SGPropertyNode * arg)
+do_switch_aircraft (const SGPropertyNode * arg, SGPropertyNode * root)
 {
     fgSetString("/sim/aircraft", arg->getStringValue("aircraft"));
     // start a reset
@@ -107,7 +107,7 @@ do_switch_aircraft (const SGPropertyNode * arg)
 /**
  */
 static bool
-do_reposition (const SGPropertyNode * arg)
+do_reposition (const SGPropertyNode * arg, SGPropertyNode * root)
 {
   fgStartReposition();
   return true;
@@ -121,7 +121,7 @@ do_reposition (const SGPropertyNode * arg)
  * and if that's unspecified, to "Panels/Default/default.xml".
  */
 static bool
-do_panel_load (const SGPropertyNode * arg)
+do_panel_load (const SGPropertyNode * arg, SGPropertyNode * root)
 {
   string panel_path = arg->getStringValue("path");
   if (!panel_path.empty()) {
@@ -139,7 +139,7 @@ do_panel_load (const SGPropertyNode * arg)
  * to FG_ROOT). Defaults to "preferences.xml".
  */
 static bool
-do_preferences_load (const SGPropertyNode * arg)
+do_preferences_load (const SGPropertyNode * arg, SGPropertyNode * root)
 {
     // disabling this command which was formerly used to reload 'preferences.xml'
     // reloading the defaults doesn't make sense (better to reset the simulator),
@@ -154,7 +154,7 @@ do_preferences_load (const SGPropertyNode * arg)
  * No parameters.
  */
 static bool
-do_toggle_fullscreen(const SGPropertyNode *arg)
+do_toggle_fullscreen(const SGPropertyNode*, SGPropertyNode*)
 {
     fgOSFullScreen();
     return true;
@@ -164,27 +164,27 @@ do_toggle_fullscreen(const SGPropertyNode *arg)
  * Built-in command: capture screen.
  */
 static bool
-do_screen_capture (const SGPropertyNode * arg)
+do_screen_capture(const SGPropertyNode*, SGPropertyNode*)
 {
   return fgDumpSnapShot();
 }
 
 static bool
-do_reload_shaders (const SGPropertyNode*)
+do_reload_shaders (const SGPropertyNode*, SGPropertyNode*)
 {
     simgear::reload_shaders();
     return true;
 }
 
 static bool
-do_dump_scene_graph (const SGPropertyNode*)
+do_dump_scene_graph (const SGPropertyNode*, SGPropertyNode*)
 {
     fgDumpSceneGraph();
     return true;
 }
 
 static bool
-do_dump_terrain_branch (const SGPropertyNode*)
+do_dump_terrain_branch (const SGPropertyNode*, SGPropertyNode*)
 {
     fgDumpTerrainBranch();
 
@@ -201,7 +201,7 @@ do_dump_terrain_branch (const SGPropertyNode*)
 }
 
 static bool
-do_print_visible_scene_info(const SGPropertyNode*)
+do_print_visible_scene_info(const SGPropertyNode*, SGPropertyNode*)
 {
     fgPrintVisibleSceneInfoCommand();
     return true;
@@ -211,7 +211,7 @@ do_print_visible_scene_info(const SGPropertyNode*)
  * Built-in command: hires capture screen.
  */
 static bool
-do_hires_screen_capture (const SGPropertyNode * arg)
+do_hires_screen_capture (const SGPropertyNode * arg, SGPropertyNode * root)
 {
   fgHiResDump();
   return true;
@@ -222,7 +222,7 @@ do_hires_screen_capture (const SGPropertyNode * arg)
  * Reload the tile cache.
  */
 static bool
-do_tile_cache_reload (const SGPropertyNode * arg)
+do_tile_cache_reload (const SGPropertyNode * arg, SGPropertyNode * root)
 {
     SGPropertyNode *master_freeze = fgGetNode("/sim/freeze/master");
     bool freeze = master_freeze->getBoolValue();
@@ -243,7 +243,7 @@ do_tile_cache_reload (const SGPropertyNode * arg)
  * Reload the materials definition
  */
 static bool
-do_materials_reload (const SGPropertyNode * arg)
+do_materials_reload (const SGPropertyNode * arg, SGPropertyNode * root)
 {
     SG_LOG(SG_INPUT, SG_INFO, "Reloading Materials");
     SGMaterialLib* new_matlib =  new SGMaterialLib;
@@ -274,7 +274,7 @@ do_materials_reload (const SGPropertyNode * arg)
  * name: the name of the GUI dialog for future reference.
  */
 static bool
-do_dialog_new (const SGPropertyNode * arg)
+do_dialog_new (const SGPropertyNode * arg, SGPropertyNode * root)
 {
     NewGUI * gui = (NewGUI *)globals->get_subsystem("gui");
     if (!gui) {
@@ -298,7 +298,7 @@ do_dialog_new (const SGPropertyNode * arg)
  * dialog-name: the name of the GUI dialog to display.
  */
 static bool
-do_dialog_show (const SGPropertyNode * arg)
+do_dialog_show (const SGPropertyNode * arg, SGPropertyNode * root)
 {
     NewGUI * gui = (NewGUI *)globals->get_subsystem("gui");
     gui->showDialog(arg->getStringValue("dialog-name"));
@@ -310,7 +310,7 @@ do_dialog_show (const SGPropertyNode * arg)
  * Built-in Command: Hide the active XML-configured dialog.
  */
 static bool
-do_dialog_close (const SGPropertyNode * arg)
+do_dialog_close (const SGPropertyNode * arg, SGPropertyNode * root)
 {
     NewGUI * gui = (NewGUI *)globals->get_subsystem("gui");
     if(arg->hasValue("dialog-name"))
@@ -325,7 +325,7 @@ do_dialog_close (const SGPropertyNode * arg)
  * object-name: The name of the GUI object(s) (all GUI objects if omitted).
  */
 static bool
-do_dialog_update (const SGPropertyNode * arg)
+do_dialog_update (const SGPropertyNode * arg, SGPropertyNode * root)
 {
     NewGUI * gui = (NewGUI *)globals->get_subsystem("gui");
     FGDialog * dialog;
@@ -343,7 +343,7 @@ do_dialog_update (const SGPropertyNode * arg)
 }
 
 static bool
-do_open_browser (const SGPropertyNode * arg)
+do_open_browser (const SGPropertyNode * arg, SGPropertyNode * root)
 {
     string path;
     if (arg->hasValue("path"))
@@ -358,7 +358,7 @@ do_open_browser (const SGPropertyNode * arg)
 }
 
 static bool
-do_open_launcher(const SGPropertyNode *)
+do_open_launcher(const SGPropertyNode*, SGPropertyNode*)
 {
 #if defined(HAVE_QT)
     bool ok = flightgear::runInAppLauncherDialog();
@@ -378,7 +378,7 @@ do_open_launcher(const SGPropertyNode *)
  * object-name: The name of the GUI object(s) (all GUI objects if omitted).
  */
 static bool
-do_dialog_apply (const SGPropertyNode * arg)
+do_dialog_apply (const SGPropertyNode * arg, SGPropertyNode * root)
 {
     NewGUI * gui = (NewGUI *)globals->get_subsystem("gui");
     FGDialog * dialog;
@@ -401,7 +401,7 @@ do_dialog_apply (const SGPropertyNode * arg)
  * unlike reinit().
  */
 static bool
-do_gui_redraw (const SGPropertyNode * arg)
+do_gui_redraw (const SGPropertyNode * arg, SGPropertyNode * root)
 {
     NewGUI * gui = (NewGUI *)globals->get_subsystem("gui");
     gui->redraw();
@@ -414,7 +414,7 @@ do_gui_redraw (const SGPropertyNode * arg)
  * is returned in property "property".
  */
 static bool
-do_add_model (const SGPropertyNode * arg)
+do_add_model (const SGPropertyNode * arg, SGPropertyNode * root)
 {
     SGPropertyNode * model = fgGetNode("models", true);
     int i;
@@ -434,7 +434,7 @@ do_add_model (const SGPropertyNode * arg)
  * Built-in command: commit presets (read from in /sim/presets/)
  */
 static bool
-do_presets_commit (const SGPropertyNode * arg)
+do_presets_commit (const SGPropertyNode * arg, SGPropertyNode * root)
 {
     if (fgGetBool("/sim/initialized", false)) {
       fgResetIdleState();
@@ -449,7 +449,7 @@ do_presets_commit (const SGPropertyNode * arg)
 }
 
 static bool
-do_press_cockpit_button (const SGPropertyNode *arg)
+do_press_cockpit_button (const SGPropertyNode * arg, SGPropertyNode * root)
 {
   const char *prefix = arg->getStringValue("prefix");
 
@@ -471,7 +471,7 @@ do_press_cockpit_button (const SGPropertyNode *arg)
 }
 
 static bool
-do_release_cockpit_button (const SGPropertyNode *arg)
+do_release_cockpit_button (const SGPropertyNode * arg, SGPropertyNode * root)
 {
   const char *prefix = arg->getStringValue("prefix");
 

src/Main/subsystemFactory.cxx

@@ -188,18 +188,18 @@ static SGSubsystem* getSubsystem(const SGPropertyNode* arg, bool create)
 }
 
 static bool
-do_check_subsystem_running(const SGPropertyNode* arg)
+do_check_subsystem_running(const SGPropertyNode * arg, SGPropertyNode * root)
 {
   return getSubsystem(arg, false) != 0;
 }
 
 static bool
-do_add_subsystem (const SGPropertyNode * arg)
+do_add_subsystem (const SGPropertyNode * arg, SGPropertyNode * root)
 {
   return getSubsystem(arg, true) != 0;
 }
 
-static bool do_remove_subsystem(const SGPropertyNode * arg)
+static bool do_remove_subsystem(const SGPropertyNode * arg, SGPropertyNode * root)
 {
   std::string name = arg->getStringValue("subsystem");
 
@@ -226,7 +226,7 @@ static bool do_remove_subsystem(const SGPropertyNode * arg)
  * none is specified, reinitialize all of them.
  */
 static bool
-do_reinit (const SGPropertyNode * arg)
+do_reinit (const SGPropertyNode * arg, SGPropertyNode * root)
 {
     bool result = true;
 
@@ -258,7 +258,7 @@ do_reinit (const SGPropertyNode * arg)
  * subsystem[*] - the name(s) of the subsystem(s) to suspend.
  */
 static bool
-do_suspend (const SGPropertyNode * arg)
+do_suspend (const SGPropertyNode * arg, SGPropertyNode * root)
 {
     bool result = true;
 
@@ -282,7 +282,7 @@ do_suspend (const SGPropertyNode * arg)
  * subsystem[*] - the name(s) of the subsystem(s) to suspend.
  */
 static bool
-do_resume (const SGPropertyNode * arg)
+do_resume (const SGPropertyNode * arg, SGPropertyNode * root)
 {
     bool result = true;
 

src/Model/panelnode.cxx

@@ -430,7 +430,7 @@ osg::Node* FGPanelNode::load(SGPropertyNode *n)
  * y-pos: the y position of the mouse click.
  */
 bool
-FGPanelNode::panelMouseClickCommand(const SGPropertyNode * arg)
+FGPanelNode::panelMouseClickCommand(const SGPropertyNode * arg, SGPropertyNode * root)
 {
     return _panel->doMouseAction(arg->getIntValue("button"),
                          arg->getBoolValue("is-down") ? PU_DOWN : PU_UP,

src/Model/panelnode.hxx

@@ -64,7 +64,7 @@ private:
     void commonInit();
     void initWithPanel();
     
-    bool panelMouseClickCommand(const SGPropertyNode * arg);
+    bool panelMouseClickCommand(const SGPropertyNode * arg, SGPropertyNode * root);
     
     const bool _is2d;
     SGSharedPtr<FGPanel> _panel;

src/MultiPlayer/multiplaymgr.cxx

@@ -57,8 +57,7 @@
 using namespace std;
 
 #define MAX_PACKET_SIZE 1200
-#define MAX_TEXT_SIZE 128
+#define MAX_TEXT_SIZE 768 // Increased for 2017.3 to allow for long Emesary messages.
-
 /*
  * With the MP2017(V2) protocol it should be possible to transmit using a different type/encoding than the property has,
  * so it should be possible to transmit a bool as 
@@ -102,7 +101,21 @@ const int V2_PAD_MAGIC = 0x1face002;
  * These parameters define where these are mapped and how they are sent.
  * The blocks should be in the same property range (with no other properties inside the range)
  */
-const int BOOLARRAY_BLOCKSIZE = 40; 
+const int BOOLARRAY_BLOCKSIZE = 40;
+
+/*
+* 2017.3 introduces a new Generic Packet concept.
+* This allows a model to choose to only transmit a few essential properties, which leaves the packet at around 380 bytes.
+* The rest of the packet can then be used for bridged Emesary notifications, which over allow much more control
+* at the model level, including different notifications being sent.
+* see $FGData/Nasal/Notifications.nas and $FGData/Nasal/emesary_mp_bridge.nas
+*/
+static inline bool IsIncludedInGenericPacket(int property_id)
+{
+    return property_id >= 10002
+        || (property_id >= 1500 && property_id < 1600); // include chat and generic properties.
+}
+
 const int BOOLARRAY_BASE_1 = 11000;
 const int BOOLARRAY_BASE_2 = BOOLARRAY_BASE_1 + BOOLARRAY_BLOCKSIZE;
 const int BOOLARRAY_BASE_3 = BOOLARRAY_BASE_2 + BOOLARRAY_BLOCKSIZE;
@@ -718,7 +731,7 @@ private:
 //  txport: outgoing port number (default: 5000)
 //  rxport: incoming port number (default: 5000)
 //////////////////////////////////////////////////////////////////////
-static bool do_multiplayer_connect(const SGPropertyNode * arg) {
+static bool do_multiplayer_connect(const SGPropertyNode * arg, SGPropertyNode * root) {
    FGMultiplayMgr * self = (FGMultiplayMgr*) globals->get_subsystem("mp");
    if (!self) {
       SG_LOG(SG_NETWORK, SG_WARN, "Multiplayer subsystem not available.");
@@ -753,7 +766,7 @@ static bool do_multiplayer_connect(const SGPropertyNode * arg) {
 //  disconnect args:
 //  none
 //////////////////////////////////////////////////////////////////////
-static bool do_multiplayer_disconnect(const SGPropertyNode * arg) {
+static bool do_multiplayer_disconnect(const SGPropertyNode * arg, SGPropertyNode * root) {
    FGMultiplayMgr * self = (FGMultiplayMgr*) globals->get_subsystem("mp");
    if (!self) {
       SG_LOG(SG_NETWORK, SG_WARN, "Multiplayer subsystem not available.");
@@ -774,7 +787,7 @@ static bool do_multiplayer_disconnect(const SGPropertyNode * arg) {
 //////////////////////////////////////////////////////////////////////
 
 static bool
-do_multiplayer_refreshserverlist (const SGPropertyNode * arg)
+do_multiplayer_refreshserverlist (const SGPropertyNode * arg, SGPropertyNode * root)
 {
   using namespace simgear;
 
@@ -844,6 +857,7 @@ FGMultiplayMgr::FGMultiplayMgr()
   pXmitLen = fgGetNode("/sim/multiplay/last-xmit-packet-len", true);
   pProtocolVersion = fgGetNode("/sim/multiplay/protocol-version", true);
   pMultiPlayDebugLevel = fgGetNode("/sim/multiplay/debug-level", true);
+  pMultiPlayTransmitOnlyGenerics = fgGetNode("/sim/multiplay/transmit-only-generics", true);
   pMultiPlayRange = fgGetNode("/sim/multiplay/visibility-range-nm", true);
   pMultiPlayRange->setIntValue(100);
 } // FGMultiplayMgr::FGMultiplayMgr()
@@ -1106,7 +1120,7 @@ void
 FGMultiplayMgr::SendMyPosition(const FGExternalMotionData& motionInfo)
 {
   int protocolToUse = getProtocolToUse();
-    
+  int transmitOnlyGenerics = pMultiPlayTransmitOnlyGenerics->getIntValue();
   if ((! mInitialised) || (! mHaveServer))
         return;
 
@@ -1214,7 +1228,14 @@ FGMultiplayMgr::SendMyPosition(const FGExternalMotionData& motionInfo)
                   ++it;
                   continue;
               }
-
+              /*
+               * If requested only transmit the generic properties.
+               */
+              if (transmitOnlyGenerics && !IsIncludedInGenericPacket(propDef->id))
+              {
+                  ++it;
+                  continue;
+              }
               /*
                * 2017.2 partitions the buffer sent into protocol versions. Originally this was intended to allow
                * compatability with older clients; however this will only work in the future or with support from fgms

src/MultiPlayer/multiplaymgr.hxx

@@ -115,6 +115,7 @@ private:
   SGPropertyNode *pXmitLen;
   SGPropertyNode *pMultiPlayDebugLevel;
   SGPropertyNode *pMultiPlayRange;
+  SGPropertyNode *pMultiPlayTransmitOnlyGenerics;
 
   typedef std::map<unsigned int, const struct IdPropertyList*> PropertyDefinitionMap;
   PropertyDefinitionMap mPropertyDefinition;

src/Network/http/PropertyChangeWebsocket.cxx

@@ -114,7 +114,7 @@ static void handleExecCommand(cJSON* json)
   SGPropertyNode_ptr arg(new SGPropertyNode);
   JSON::addChildrenToProp( json, arg );
   
-  globals->get_commands()->execute(name->valuestring, arg);
+  globals->get_commands()->execute(name->valuestring, arg, nullptr);
 }
   
 PropertyChangeWebsocket::PropertyChangeWebsocket(PropertyChangeObserver * propertyChangeObserver)

src/Network/http/RunUriHandler.cxx

@@ -50,7 +50,7 @@ bool RunUriHandler::handleRequest( const HTTPRequest & request, HTTPResponse & r
   SG_LOG( SG_NETWORK, SG_INFO, "RunUriHandler("<< request.Content << "): command='" << command << "', arg='" << JSON::toJsonString(false,args,5) << "'");
 
   cJSON_Delete( json );
-  if ( globals->get_commands()->execute(command.c_str(), args) ) {
+  if ( globals->get_commands()->execute(command.c_str(), args, nullptr) ) {
     response.Content = "ok.";
     return true;
   } 

src/Network/props.cxx

@@ -384,7 +384,7 @@ PropsChannel::foundTerminator()
                         node->setStringValue( tokens[i].c_str() );
                     }
                     if ( !globals->get_commands()
-                             ->execute( "reinit", &args) )
+                             ->execute( "reinit", &args, nullptr) )
                     {
                         SG_LOG( SG_NETWORK, SG_ALERT,
                                 "Command " << tokens[1] << " failed.");
@@ -449,7 +449,7 @@ PropsChannel::foundTerminator()
                        }
                     }
                     if ( !globals->get_commands()
-                             ->execute(tokens[1].c_str(), &args) )
+                             ->execute(tokens[1].c_str(), &args, nullptr) )
                     {
                         SG_LOG( SG_NETWORK, SG_ALERT,
                                 "Command " << tokens[1] << " failed.");

src/Scripting/NasalSys.cxx

@@ -490,7 +490,7 @@ static naRef f_fgcommand(naContext c, naRef me, int argc, naRef* args)
     else
         node = new SGPropertyNode;
 
-    return naNum(globals->get_commands()->execute(naStr_data(cmd), node));
+    return naNum(globals->get_commands()->execute(naStr_data(cmd), node, nullptr));
 }
 
 // settimer(func, dt, simtime) extension function.  Falls through to
@@ -662,7 +662,7 @@ public:
         _sys->gcRelease(_gcRoot);
     }
 
-    virtual bool operator()(const SGPropertyNode* aNode)
+    virtual bool operator()(const SGPropertyNode* aNode, SGPropertyNode * root)
     {
         _sys->setCmdArg(const_cast<SGPropertyNode*>(aNode));
         naRef args[1];
@@ -1278,7 +1278,8 @@ naRef FGNasalSys::parse(naContext ctx, const char* filename, const char* buf, in
 bool FGNasalSys::handleCommand( const char* moduleName,
                                 const char* fileName,
                                 const char* src,
-                                const SGPropertyNode* arg )
+                                const SGPropertyNode* arg,
+                                SGPropertyNode* root)
 {
     naContext ctx = naNewContext();
     naRef code = parse(ctx, fileName, src, strlen(src));
@@ -1310,7 +1311,7 @@ bool FGNasalSys::handleCommand( const char* moduleName,
     return true;
 }
 
-bool FGNasalSys::handleCommand(const SGPropertyNode* arg)
+bool FGNasalSys::handleCommand(const SGPropertyNode * arg, SGPropertyNode * root)
 {
   const char* src = arg->getStringValue("script");
   const char* moduleName = arg->getStringValue("module");
@@ -1318,7 +1319,8 @@ bool FGNasalSys::handleCommand(const SGPropertyNode* arg)
   return handleCommand( moduleName,
                         arg->getPath(true).c_str(),
                         src,
-                        arg );
+                        arg,
+                        root);
 }
 
 // settimer(func, dt, simtime) extension function.  The first argument

src/Scripting/NasalSys.hxx

@@ -80,8 +80,9 @@ public:
     virtual bool handleCommand( const char* moduleName,
                                 const char* fileName,
                                 const char* src,
-                                const SGPropertyNode* arg = 0 );
+                                const SGPropertyNode* arg = 0,
-    virtual bool handleCommand(const SGPropertyNode* arg);
+                                SGPropertyNode* root = 0);
+    virtual bool handleCommand(const SGPropertyNode* arg, SGPropertyNode *root);
 
     bool createModule(const char* moduleName, const char* fileName,
                       const char* src, int len, const SGPropertyNode* cmdarg=0,

src/Sound/soundmanager.cxx

@@ -208,7 +208,7 @@ void FGSoundManager::update(double dt)
  * into a queue.  Messages are played sequentially so they do not
  * overlap.
  */
-bool FGSoundManager::playAudioSampleCommand(const SGPropertyNode * arg)
+bool FGSoundManager::playAudioSampleCommand(const SGPropertyNode * arg, SGPropertyNode * root)
 {
     string path = arg->getStringValue("path");
     string file = arg->getStringValue("file");

src/Sound/soundmanager.hxx

@@ -53,7 +53,7 @@ public:
 private:
     bool stationaryView() const;
 
-    bool playAudioSampleCommand(const SGPropertyNode * arg);
+    bool playAudioSampleCommand(const SGPropertyNode * arg, SGPropertyNode * root);
 
     SGSharedPtr<FGSampleQueue> _chatterQueue;
 

src/Time/TimeManager.cxx

@@ -37,7 +37,7 @@
 
 using std::string;
 
-static bool do_timeofday (const SGPropertyNode * arg)
+static bool do_timeofday (const SGPropertyNode * arg, SGPropertyNode * root)
 {
     const string &offset_type = arg->getStringValue("timeofday", "noon");
     int offset = arg->getIntValue("offset", 0);

src/Viewer/GraphicsWindowQt5.cpp

@@ -900,7 +900,9 @@ namespace flightgear
 
 void initQtWindowingSystem()
 {
-osg::GraphicsContext::setWindowingSystemInterface(Qt5WindowingSystem::getInterface());
+#if OSG_VERSION_LESS_THAN(3,5,2)
+    osg::GraphicsContext::setWindowingSystemInterface(Qt5WindowingSystem::getInterface());
+#endif
 }
 
 } // of namespace flightgear