From 0f590280c7712afc5e59d186dda83badc07059e8 Mon Sep 17 00:00:00 2001
From: James Turner <zakalawe@mac.com>
Date: Fri, 18 Dec 2015 20:13:23 -0800
Subject: [PATCH] Aircraft-model subsystem behaves better

- make shutdown logic more robust
- shutdown is no longer special cased in globals.
---
 src/Main/fg_init.cxx  |  2 +-
 src/Main/globals.cxx  |  2 --
 src/Model/acmodel.cxx | 19 +++++++++++--------
 src/Model/acmodel.hxx |  1 +
 4 files changed, 13 insertions(+), 11 deletions(-)

diff --git a/src/Main/fg_init.cxx b/src/Main/fg_init.cxx
index 012f14371..b5c30e6d6 100644
--- a/src/Main/fg_init.cxx
+++ b/src/Main/fg_init.cxx
@@ -894,7 +894,7 @@ void fgCreateSubsystems(bool duringReset) {
         globals->add_subsystem("events", globals->get_event_mgr(), SGSubsystemMgr::DISPLAY);
     }
 
-    globals->add_subsystem("aircraft-model", new FGAircraftModel, SGSubsystemMgr::DISPLAY);
+    globals->add_new_subsystem<FGAircraftModel>(SGSubsystemMgr::DISPLAY);
     globals->add_new_subsystem<FGModelMgr>(SGSubsystemMgr::DISPLAY);
 
     globals->add_new_subsystem<FGViewMgr>(SGSubsystemMgr::DISPLAY);
diff --git a/src/Main/globals.cxx b/src/Main/globals.cxx
index 7e22bcfd3..e3f7cbcf3 100644
--- a/src/Main/globals.cxx
+++ b/src/Main/globals.cxx
@@ -215,8 +215,6 @@ FGGlobals::~FGGlobals()
     subsystem_mgr->shutdown();
     subsystem_mgr->unbind();
 
-    subsystem_mgr->remove("aircraft-model");
-
     subsystem_mgr->remove(FGTileMgr::subsystemName());
 
     osg::ref_ptr<osgViewer::Viewer> vw(renderer->getViewer());
diff --git a/src/Model/acmodel.cxx b/src/Model/acmodel.cxx
index 782145ebe..37ef66fd0 100644
--- a/src/Model/acmodel.cxx
+++ b/src/Model/acmodel.cxx
@@ -139,17 +139,20 @@ FGAircraftModel::reinit()
 void
 FGAircraftModel::shutdown()
 {
-  if (!_aircraft.get()) {
-    return;
-  }
-  
-  osg::Node* node = _aircraft->getSceneGraph();
-  globals->get_scenery()->get_aircraft_branch()->removeChild(node);
+    FGScenery* scenery = globals->get_scenery();
+
+    if (_aircraft.get()) {
+        if (scenery && scenery->get_aircraft_branch()) {
+            scenery->get_aircraft_branch()->removeChild(_aircraft->getSceneGraph());
+        }
+    }
 
     if (_interior.get()) {
-        globals->get_scenery()->get_interior_branch()->removeChild(_interior->getSceneGraph());
+        if (scenery && scenery->get_interior_branch()) {
+            scenery->get_interior_branch()->removeChild(_interior->getSceneGraph());
+        }
     }
-    
+
     _aircraft.reset();
     _interior.reset();
 }
diff --git a/src/Model/acmodel.hxx b/src/Model/acmodel.hxx
index edaaad77c..ec2a9b5af 100644
--- a/src/Model/acmodel.hxx
+++ b/src/Model/acmodel.hxx
@@ -34,6 +34,7 @@ public:
   virtual SGModelPlacement * get3DModel() { return _aircraft.get(); }
   virtual SGVec3d& getVelocity() { return _velocity; }
 
+    static const char* subsystemName() { return "aircraft-model"; }
 private:
   void deinit ();