Execute load/unload Nasal for both detailed and AI

Previously only the first of a detailed/bare AI model tuple's Nasal
would be executed when the model is loaded.  This loads both.

src/AIModel/AIBase.cxx

@@ -62,7 +62,7 @@ using namespace simgear;
 class FGAIModelData : public simgear::SGModelData {
 public:
     FGAIModelData(SGPropertyNode *root = nullptr)
-        : _nasal( new FGNasalModelDataProxy(root) )
+      : _root (root)
     {
     }
 
@@ -81,7 +81,6 @@ public:
             return;
 
         _modelLoaded[path] = true;
-        _ready = true;
 
         if(prop->hasChild("interior-path")){
             _interiorPath = prop->getStringValue("interior-path");
@@ -89,9 +88,10 @@ public:
         }
 
         _fxpath = prop->getStringValue("sound/path");
-        _nasal->modelLoaded(path, prop, n);
+        _nasal[path] = std::unique_ptr<FGNasalModelDataProxy>(new FGNasalModelDataProxy(_root));
-
+        _nasal[path]->modelLoaded(path, prop, n);
-
+        _ready = true;
+        _initialized = false;
     }
 
     /** init hook to be called after model is loaded.
@@ -107,15 +107,16 @@ public:
     bool hasInteriorPath(void) { return _hasInteriorPath;}
     inline std::string& getInteriorPath() { return _interiorPath; }
 private:
-    std::unique_ptr<FGNasalModelDataProxy> _nasal;
     std::string _fxpath;
     std::string _interiorPath;
 
     std::map<string, bool> _modelLoaded;
+    std::map<string, std::unique_ptr<FGNasalModelDataProxy>> _nasal;
     bool _ready = false;
     bool _initialized = false;
     bool _hasInteriorPath = false;
     bool _interiorLoaded = false;
+    SGPropertyNode* _root;
 };
 
 FGAIBase::FGAIBase(object_type ot, bool enableHot) :
@@ -281,20 +282,7 @@ void FGAIBase::update(double dt) {
     ft_per_deg_lat = 366468.96 - 3717.12 * cos(pos.getLatitudeRad());
     ft_per_deg_lon = 365228.16 * cos(pos.getLatitudeRad());
 
-    if ( _fx )
+    if ((_modeldata)&&(_modeldata->needInitilization()))
-    {
-        // update model's audio sample values
-        _fx->set_position_geod( pos );
-
-        SGQuatd orient = SGQuatd::fromYawPitchRollDeg(hdg, pitch, roll);
-        _fx->set_orientation( orient );
-
-        SGVec3d velocity;
-        velocity = SGVec3d( speed_north_deg_sec, speed_east_deg_sec,
-                            pitch*speed );
-        _fx->set_velocity( velocity );
-    }
-    else if ((_modeldata)&&(_modeldata->needInitilization()))
     {
         // process deferred nasal initialization,
         // which must be done in main thread
@@ -308,6 +296,9 @@ void FGAIBase::update(double dt) {
             {
                 props->setStringValue("sim/sound/path", fxpath.c_str());
 
+                // Remove any existing sound FX (e.g. from another model)
+                removeSoundFx();
+
                 // initialize the sound configuration
                 std::stringstream name;
                 name <<  "aifx:";
@@ -318,6 +309,20 @@ void FGAIBase::update(double dt) {
         }
     }
 
+    if ( _fx )
+    {
+        // update model's audio sample values
+        _fx->set_position_geod( pos );
+
+        SGQuatd orient = SGQuatd::fromYawPitchRollDeg(hdg, pitch, roll);
+        _fx->set_orientation( orient );
+
+        SGVec3d velocity;
+        velocity = SGVec3d( speed_north_deg_sec, speed_east_deg_sec,
+                            pitch*speed );
+        _fx->set_velocity( velocity );
+    }
+
     updateInterior();
 }