Use the 'all but self' capability of the scenery elevaton code instead of

playing with node masks.

Modified Files:
 	src/AIModel/AIAircraft.cxx src/AIModel/AIBallistic.cxx
 	src/AIModel/AIBase.cxx src/AIModel/AIBase.hxx
 	src/AIModel/AIShip.cxx src/AIModel/AIShip.hxx
	src/AIModel/AIThermal.cxx src/ATCDCL/AILocalTraffic.cxx

src/AIModel/AIAircraft.cxx

@@ -412,7 +412,7 @@ void FGAIAircraft::getGroundElev(double dt) {
         }
 
         double alt;
-        if (globals->get_scenery()->get_elevation_m(SGGeod::fromGeodM(pos, 20000), alt, 0))
+        if (getGroundElevationM(SGGeod::fromGeodM(pos, 20000), alt, 0))
             tgt_altitude_ft = alt * SG_METER_TO_FEET;
     }
 }

src/AIModel/AIBallistic.cxx

@@ -426,8 +426,8 @@ void FGAIBallistic::setForcePath(const string& p) {
 
 bool FGAIBallistic::getHtAGL(){
 
-    if (globals->get_scenery()->get_elevation_m(SGGeod::fromGeodM(pos, 10000),
+    if (getGroundElevationM(SGGeod::fromGeodM(pos, 10000),
-                                                _elevation_m, &_material)){
+                            _elevation_m, &_material)) {
             _ht_agl_ft = pos.getElevationFt() - _elevation_m * SG_METER_TO_FEET;
             if (_material) {
                 const vector<string>& names = _material->get_names();

src/AIModel/AIBase.cxx

@@ -191,8 +191,6 @@ bool FGAIBase::init(bool search_in_AI_path) {
 void FGAIBase::initModel(osg::Node *node)
 {
     if (model.valid()) {
-        // Disable altitude computations for general AI models.
-        model->setNodeMask(model->getNodeMask() & ~SG_NODEMASK_TERRAIN_BIT);
 
         fgSetString("/ai/models/model-added", props->getPath());
 
@@ -452,6 +450,12 @@ SGVec3d FGAIBase::getCartPos() const {
     return cartPos;
 }
 
+bool FGAIBase::getGroundElevationM(const SGGeod& pos, double& elev,
+                                   const SGMaterial** material) const {
+    return globals->get_scenery()->get_elevation_m(pos, elev, material,
+                                                   model.get());
+}
+
 double FGAIBase::_getCartPosX() const {
     SGVec3d cartPos = getCartPos();
     return cartPos.x();

src/AIModel/AIBase.hxx

@@ -36,6 +36,7 @@
 using std::string;
 using std::list;
 
+class SGMaterial;
 class FGAIManager;
 class FGAIFlightPlan;
 
@@ -93,6 +94,9 @@ public:
     SGVec3d getCartPosAt(const SGVec3d& off) const;
     SGVec3d getCartPos() const;
 
+    bool getGroundElevationM(const SGGeod& pos, double& elev,
+                             const SGMaterial** material) const;
+
     double _getCartPosX() const;
     double _getCartPosY() const;
     double _getCartPosZ() const;

src/AIModel/AIShip.cxx

@@ -34,7 +34,6 @@
 #include <simgear/math/sg_geodesy.hxx>
 #include <simgear/timing/sg_time.hxx>
 #include <simgear/math/sg_random.h>
-#include <simgear/scene/util/SGNodeMasks.hxx>
 
 #include "AIShip.hxx"
 
@@ -118,11 +117,6 @@ bool FGAIShip::init(bool search_in_AI_path) {
     return FGAIBase::init(search_in_AI_path);
 }
 
-void FGAIShip::initModel(osg::Node *node) {
-    FGAIBase::initModel(node);
-    model->setNodeMask(model->getNodeMask() | SG_NODEMASK_TERRAIN_BIT);
-}
-
 void FGAIShip::bind() {
     FGAIBase::bind();
 

src/AIModel/AIShip.hxx

@@ -37,7 +37,6 @@ public:
     virtual void readFromScenario(SGPropertyNode* scFileNode);
 
     virtual bool init(bool search_in_AI_path=false);
-    virtual void initModel(osg::Node *node);
     virtual void bind();
     virtual void unbind();
     virtual void update(double dt);

src/AIModel/AIThermal.cxx

@@ -229,7 +229,7 @@ double user_altitude  = manager->get_user_altitude(); // MSL
 dt_count += dt;
 if (dt_count >= 10.0 ) {
 	//double alt;
-	if (globals->get_scenery()->get_elevation_m(SGGeod::fromGeodM(pos, 20000), alt, 0)){	
+	if (getGroundElevationM(SGGeod::fromGeodM(pos, 20000), alt, 0)) {
 	ground_elev_ft =  alt * SG_METER_TO_FEET;
 	do_agl_calc = 0;
 	altitude_agl_ft = height - ground_elev_ft ;

src/ATCDCL/AILocalTraffic.cxx

@@ -1553,7 +1553,7 @@ void FGAILocalTraffic::DoGroundElev() {
 
   // FIXME: make shure the pos.lat/pos.lon values are in degrees ...
   double alt;
-  if (globals->get_scenery()->get_elevation_m(SGGeod::fromGeodM(_aip.getPosition(), 20000), alt, 0))
+  if (globals->get_scenery()->get_elevation_m(SGGeod::fromGeodM(_aip.getPosition(), 20000), alt, 0, _aip.getSceneGraph()))
     _ground_elevation_m = alt;
 }