diff --git a/src/BuildTiles/Clipper/clipper.cxx b/src/BuildTiles/Clipper/clipper.cxx
index e105f2a1..2d13f80a 100644
--- a/src/BuildTiles/Clipper/clipper.cxx
+++ b/src/BuildTiles/Clipper/clipper.cxx
@@ -44,27 +44,28 @@ SG_USING_STD(cout);
 
 
 // Constructor.
-FGClipper::FGClipper() {
+TGClipper::TGClipper() {
 }
 
 
 // Destructor.
-FGClipper::~FGClipper() {
+TGClipper::~TGClipper() {
 }
 
 
 // Initialize the clipper (empty all the polygon buckets.)
-bool FGClipper::init() {
-    for ( int i = 0; i < FG_MAX_AREA_TYPES; ++i ) {
+bool TGClipper::init() {
+    for ( int i = 0; i < TG_MAX_AREA_TYPES; ++i ) {
 	polys_in.polys[i].clear();
     }
+    fixed_elevations.clear();
 
     return true;
 }
 
 
 // Load a polygon definition file.
-bool FGClipper::load_polys(const string& path) {
+bool TGClipper::load_polys(const string& path) {
     bool poly3d = false;
     string first_line;
     string poly_name;
@@ -127,9 +128,8 @@ bool FGClipper::load_polys(const string& path) {
                 startz = -9999.0;
             }
 	    p = Point3D(startx, starty, startz);
-	    // cout << "load poly's: poly pt = " << p << endl;
 	    poly.add_node( i, p );
-	    SG_LOG( SG_CLIPPER, SG_BULK, "0 = " << p );
+            fixed_elevations.unique_add( p );
 
 	    for ( j = 1; j < count - 1; ++j ) {
 		in >> x;
@@ -140,8 +140,8 @@ bool FGClipper::load_polys(const string& path) {
                     z = -9999.0;
                 }
 		p = Point3D( x, y, z );
-                // cout << "load poly's: poly pt = " << p << endl;
 		poly.add_node( i, p );
+                fixed_elevations.unique_add( p );
 	    }
 
 	    in >> lastx;
@@ -158,8 +158,8 @@ bool FGClipper::load_polys(const string& path) {
 		// last point same as first, discard
 	    } else {
 		p = Point3D( lastx, lasty, lastz );
-                // cout << "load poly's: poly pt = " << p << endl;
 		poly.add_node( i, p );
+                fixed_elevations.unique_add( p );
 	    }
 	}
 
@@ -179,7 +179,7 @@ bool FGClipper::load_polys(const string& path) {
 
 // Load a polygon definition file containing osgb36 Eastings and Northings
 // and convert them to WGS84 Latitude and Longitude
-bool FGClipper::load_osgb36_polys(const string& path) {
+bool TGClipper::load_osgb36_polys(const string& path) {
 //   cout << "Loading osgb36 poly\n";
     string poly_name;
     AreaType poly_type = DefaultArea;
@@ -288,7 +288,7 @@ bool FGClipper::load_osgb36_polys(const string& path) {
     // TEST - Ignore
     // } else
 
-    if ( area < FG_MAX_AREA_TYPES ) {
+    if ( area < TG_MAX_AREA_TYPES ) {
 	polys_in.polys[area].push_back(poly);
     } else {
 	SG_LOG( SG_CLIPPER, SG_ALERT, "Polygon type out of range = "
@@ -303,9 +303,9 @@ bool FGClipper::load_osgb36_polys(const string& path) {
 }
 
 // Add a polygon to the clipper.
-void FGClipper::add_poly( int area, const TGPolygon &poly )
+void TGClipper::add_poly( int area, const TGPolygon &poly )
 {
-    if ( area < FG_MAX_AREA_TYPES ) {
+    if ( area < TG_MAX_AREA_TYPES ) {
 	polys_in.polys[area].push_back(poly);
     } else {
 	SG_LOG( SG_CLIPPER, SG_ALERT, "Polygon type out of range = " 
@@ -316,7 +316,7 @@ void FGClipper::add_poly( int area, const TGPolygon &poly )
 
 
 // Move slivers from in polygon to out polygon.
-void FGClipper::move_slivers( TGPolygon& in, TGPolygon& out ) {
+void TGClipper::move_slivers( TGPolygon& in, TGPolygon& out ) {
     // traverse each contour of the polygon and attempt to identify
     // likely slivers
 
@@ -377,7 +377,7 @@ void FGClipper::move_slivers( TGPolygon& in, TGPolygon& out ) {
 // a polygon with no increased contours (i.e. the sliver is adjacent
 // and can be merged.)  If so, replace the clipped polygon with the
 // new polygon that has the sliver merged in.
-void FGClipper::merge_slivers( FGPolyList& clipped, TGPolygon& slivers ) {
+void TGClipper::merge_slivers( TGPolyList& clipped, TGPolygon& slivers ) {
     TGPolygon poly, result, sliver;
     point_list contour;
     int original_contours, result_contours;
@@ -393,7 +393,7 @@ void FGClipper::merge_slivers( FGPolyList& clipped, TGPolygon& slivers ) {
 	sliver.add_contour( contour, 0 );
 	done = false;
 
-	for ( area = 0; area < FG_MAX_AREA_TYPES && !done; ++area ) {
+	for ( area = 0; area < TG_MAX_AREA_TYPES && !done; ++area ) {
 
 	    if ( area == HoleArea ) {
 		// don't merge a non-hole sliver in with a hole
@@ -468,7 +468,7 @@ is_water_area (AreaType type)
 
 // Clip all the polygons against each other in a priority scheme based
 // on order of the polygon type in the polygon type enum.
-bool FGClipper::clip_all(const point2d& min, const point2d& max) {
+bool TGClipper::clip_all(const point2d& min, const point2d& max) {
     TGPolygon accum, tmp;
     TGPolygon slivers, remains;
     int i, j;
@@ -503,7 +503,7 @@ bool FGClipper::clip_all(const point2d& min, const point2d& max) {
     // set up a mask for all water.
     TGPolygon water_mask;
     water_mask.erase();
-    for ( i = 0; i < FG_MAX_AREA_TYPES; i++ ) {
+    for ( i = 0; i < TG_MAX_AREA_TYPES; i++ ) {
         if (is_water_area(AreaType(i))) {
             for (unsigned int j = 0; j < polys_in.polys[i].size(); j++) {
                 water_mask =
@@ -521,7 +521,7 @@ bool FGClipper::clip_all(const point2d& min, const point2d& max) {
     }
 
     // process polygons in priority order
-    for ( i = 0; i < FG_MAX_AREA_TYPES; ++i ) {
+    for ( i = 0; i < TG_MAX_AREA_TYPES; ++i ) {
 	cout << "num polys of type (" << i << ") = " 
 	     << polys_in.polys[i].size() << endl;
 	// current = polys_in.polys[i].begin();
diff --git a/src/BuildTiles/Clipper/clipper.hxx b/src/BuildTiles/Clipper/clipper.hxx
index 63ddc804..2989e601 100644
--- a/src/BuildTiles/Clipper/clipper.hxx
+++ b/src/BuildTiles/Clipper/clipper.hxx
@@ -36,6 +36,7 @@
 #include <simgear/compiler.h>
 #include <simgear/math/sg_types.hxx>
 
+#include <Geometry/trinodes.hxx>
 #include <Polygon/polygon.hxx>
 
 #include STL_STRING
@@ -45,33 +46,34 @@ SG_USING_STD(string);
 SG_USING_STD(vector);
 
 
-#define FG_MAX_AREA_TYPES 128	// FIXME also defined in
+#define TG_MAX_AREA_TYPES 128	// FIXME also defined in
                                 // MergerClipper/clipper.hxx
 #define EXTRA_SAFETY_CLIP
 
 
-class FGPolyList
+class TGPolyList
 {
 public:
-    poly_list polys[FG_MAX_AREA_TYPES];
+    poly_list polys[TG_MAX_AREA_TYPES];
     TGPolygon safety_base;
 };
 
 
-class FGClipper 
+class TGClipper 
 {
 
 private:
 
-    FGPolyList polys_in, polys_clipped;
+    TGPolyList polys_in, polys_clipped;
+    TGTriNodes fixed_elevations;
 
 public:
 
     // Constructor.
-    FGClipper (void);
+    TGClipper (void);
 
     // Destructor.
-    ~FGClipper (void);
+    ~TGClipper (void);
 
     // Initialize Clipper (allocate and/or connect structures.)
     bool init();
@@ -93,13 +95,16 @@ public:
     // yields a polygon with no increased contours (i.e. the sliver is
     // adjacent and can be merged.)  If so, replace the clipped
     // polygon with the new polygon that has the sliver merged in.
-    void merge_slivers( FGPolyList& clipped, TGPolygon& slivers );
+    void merge_slivers( TGPolyList& clipped, TGPolygon& slivers );
     
     // Do actual clipping work.
     bool clip_all(const point2d& min, const point2d& max);
 
     // Return output poly list
-    inline FGPolyList get_polys_clipped() const { return polys_clipped; }
+    inline TGPolyList get_polys_clipped() const { return polys_clipped; }
+
+    // Return the fixed elevation points list
+    inline TGTriNodes get_fixed_elevations() const { return fixed_elevations; }
 };
 
 
diff --git a/src/BuildTiles/Clipper/testclipper.cxx b/src/BuildTiles/Clipper/testclipper.cxx
index 41790033..f736384d 100644
--- a/src/BuildTiles/Clipper/testclipper.cxx
+++ b/src/BuildTiles/Clipper/testclipper.cxx
@@ -39,7 +39,7 @@ int main( int argc, char **argv ) {
     global_min.x = global_min.y = 200;
     global_max.y = global_max.x = -200;
 
-    FGClipper clipper;
+    TGClipper clipper;
     clipper.init();
 
     if ( argc < 2 ) {
diff --git a/src/BuildTiles/GenOutput/genobj.cxx b/src/BuildTiles/GenOutput/genobj.cxx
index 3d2288f6..faba0f59 100644
--- a/src/BuildTiles/GenOutput/genobj.cxx
+++ b/src/BuildTiles/GenOutput/genobj.cxx
@@ -46,7 +46,7 @@ SG_USING_STD(endl);
 
 // calculate the global bounding sphere.  Center is the center of the
 // tile and zero elevation
-void FGGenOutput::calc_gbs( FGConstruct& c ) {
+void TGGenOutput::calc_gbs( TGConstruct& c ) {
     double dist_squared;
     double radius_squared = 0;
     
@@ -77,7 +77,7 @@ void FGGenOutput::calc_gbs( FGConstruct& c ) {
 
 // traverse the specified fan and attempt to calculate "none
 // stretching" texture coordinates
-int_list FGGenOutput::calc_tex_coords( FGConstruct& c, point_list geod_nodes,
+int_list TGGenOutput::calc_tex_coords( TGConstruct& c, point_list geod_nodes,
 				       int_list fan )
 {
     // cout << "calculating texture coordinates for a specific fan of size = "
@@ -162,7 +162,7 @@ int_list FGGenOutput::calc_tex_coords( FGConstruct& c, point_list geod_nodes,
 
 // build the necessary output structures based on the triangulation
 // data
-int FGGenOutput::build( FGConstruct& c ) {
+int TGGenOutput::build( TGConstruct& c ) {
     int i, j;
 
     TGTriNodes trinodes = c.get_tri_nodes();
@@ -176,7 +176,7 @@ int FGGenOutput::build( FGConstruct& c ) {
     // build the trifan list
     cout << "total triangles = " << tri_elements.size() << endl;
     TGGenFans f;
-    for ( i = 0; i < FG_MAX_AREA_TYPES; ++i ) {
+    for ( i = 0; i < TG_MAX_AREA_TYPES; ++i ) {
 	triele_list area_tris;
 	area_tris.erase( area_tris.begin(), area_tris.end() );
 
@@ -199,7 +199,7 @@ int FGGenOutput::build( FGConstruct& c ) {
     cout << "calculating texture coordinates" << endl;
     tex_coords.clear();
 
-    for ( i = 0; i < FG_MAX_AREA_TYPES; ++i ) {
+    for ( i = 0; i < TG_MAX_AREA_TYPES; ++i ) {
 	for ( j = 0; j < (int)fans[i].size(); ++j ) {
 	    // int_list t_list = calc_tex_coords( c, geod_nodes, fans[i][j] );
 	    // cout << fans[i][j].size() << " === " 
@@ -238,7 +238,7 @@ int FGGenOutput::build( FGConstruct& c ) {
 
 
 // caclulate the bounding sphere for a list of triangle faces
-void FGGenOutput::calc_group_bounding_sphere( FGConstruct& c, 
+void TGGenOutput::calc_group_bounding_sphere( TGConstruct& c, 
 					      const opt_list& fans, 
 					      Point3D *center, double *radius )
 {
@@ -290,7 +290,7 @@ void FGGenOutput::calc_group_bounding_sphere( FGConstruct& c,
 
 
 // caclulate the bounding sphere for the specified triangle face
-void FGGenOutput::calc_bounding_sphere( FGConstruct& c, const FGTriEle& t, 
+void TGGenOutput::calc_bounding_sphere( TGConstruct& c, const TGTriEle& t, 
 					Point3D *center, double *radius )
 {
     point_list wgs84_nodes = c.get_wgs84_nodes();
@@ -328,7 +328,7 @@ void FGGenOutput::calc_bounding_sphere( FGConstruct& c, const FGTriEle& t,
 
 #if 0
 // write out the fgfs scenery file
-int FGGenOutput::write_orig( FGConstruct &c ) {
+int TGGenOutput::write_orig( TGConstruct &c ) {
     Point3D p;
     int i;
 
@@ -410,7 +410,7 @@ int FGGenOutput::write_orig( FGConstruct &c ) {
     fprintf(fp, "\n");
 
     int total_tris = 0;
-    for ( i = 0; i < FG_MAX_AREA_TYPES; ++i ) {
+    for ( i = 0; i < TG_MAX_AREA_TYPES; ++i ) {
 	if ( (int)fans[i].size() > 0 ) {
 	    string attr_name = get_area_name( (AreaType)i );
 	    calc_group_bounding_sphere( c, fans[i], &center, &radius );
@@ -446,7 +446,7 @@ int FGGenOutput::write_orig( FGConstruct &c ) {
 
 
 // write out the fgfs scenery file
-int FGGenOutput::write( FGConstruct &c ) {
+int TGGenOutput::write( TGConstruct &c ) {
     int i;
 
     // Assemble all the data into the final format
@@ -475,7 +475,7 @@ int FGGenOutput::write( FGConstruct &c ) {
     group_list fans_v;   group_list fans_tc;   string_list fan_materials;
     fans_v.clear();      fans_tc.clear();      fan_materials.clear();
 
-    for ( i = 0; i < FG_MAX_AREA_TYPES; ++i ) {
+    for ( i = 0; i < TG_MAX_AREA_TYPES; ++i ) {
 	if ( (int)fans[i].size() > 0 ) {
 	    cout << "creating " << fans[i].size() << " fans of type "
 		 << i << endl;
diff --git a/src/BuildTiles/GenOutput/genobj.hxx b/src/BuildTiles/GenOutput/genobj.hxx
index 1a29a92e..ed7d487e 100644
--- a/src/BuildTiles/GenOutput/genobj.hxx
+++ b/src/BuildTiles/GenOutput/genobj.hxx
@@ -52,7 +52,7 @@ typedef vector < int_list > tex_list;
 typedef tex_list::iterator tex_list_iterator;
 typedef tex_list::const_iterator const_tex_list_iterator;
 
-class FGGenOutput {
+class TGGenOutput {
 
 private:
 
@@ -66,10 +66,10 @@ private:
     TGTriNodes tex_coords;
 
     // fan list
-    opt_list fans[FG_MAX_AREA_TYPES];
+    opt_list fans[TG_MAX_AREA_TYPES];
 
     // textures pointer list
-    tex_list textures[FG_MAX_AREA_TYPES];
+    tex_list textures[TG_MAX_AREA_TYPES];
 
     // global bounding sphere
     Point3D gbs_center;
@@ -77,32 +77,32 @@ private:
 
     // calculate the global bounding sphere.  Center is the average of
     // the points.
-    void calc_gbs( FGConstruct& c );
+    void calc_gbs( TGConstruct& c );
 
     // caclulate the bounding sphere for a list of triangle faces
-    void calc_group_bounding_sphere( FGConstruct& c, const opt_list& fans, 
+    void calc_group_bounding_sphere( TGConstruct& c, const opt_list& fans, 
 				     Point3D *center, double *radius );
 
     // caclulate the bounding sphere for the specified triangle face
-    void calc_bounding_sphere( FGConstruct& c, const FGTriEle& t, 
+    void calc_bounding_sphere( TGConstruct& c, const TGTriEle& t, 
 			       Point3D *center, double *radius );
 
     // traverse the specified fan and attempt to calculate "none
     // stretching" texture coordinates
-    // int_list calc_tex_coords( FGConstruct& c, point_list geod_nodes, int_list fan );
+    // int_list calc_tex_coords( TGConstruct& c, point_list geod_nodes, int_list fan );
 
 public:
 
     // Constructor && Destructor
-    inline FGGenOutput() { }
-    inline ~FGGenOutput() { }
+    inline TGGenOutput() { }
+    inline ~TGGenOutput() { }
 
     // build the necessary output structures based on the
     // triangulation data
-    int build( FGConstruct& c );
+    int build( TGConstruct& c );
 
     // write out the fgfs scenery file
-    int write( FGConstruct &c );
+    int write( TGConstruct &c );
 };
 
 
diff --git a/src/BuildTiles/Main/construct.cxx b/src/BuildTiles/Main/construct.cxx
index 04ced791..b43843e9 100644
--- a/src/BuildTiles/Main/construct.cxx
+++ b/src/BuildTiles/Main/construct.cxx
@@ -26,8 +26,8 @@
 
 
 // Constructor
-FGConstruct::FGConstruct() { }
+TGConstruct::TGConstruct() { }
 
 
 // Destructor
-FGConstruct::~FGConstruct() { }
+TGConstruct::~TGConstruct() { }
diff --git a/src/BuildTiles/Main/construct.hxx b/src/BuildTiles/Main/construct.hxx
index 194081c0..61c6cb5c 100644
--- a/src/BuildTiles/Main/construct.hxx
+++ b/src/BuildTiles/Main/construct.hxx
@@ -32,7 +32,7 @@
 
 
 // Maximum nodes per tile
-#define FG_MAX_NODES 4000
+#define TG_MAX_NODES 4000
 
 
 #include <simgear/compiler.h>
@@ -55,7 +55,7 @@ typedef belongs_to_list::iterator belongs_to_list_iterator;
 typedef belongs_to_list::const_iterator belongs_to_list_tripoly_iterator;
 
 
-class FGConstruct {
+class TGConstruct {
 
 private:
 
@@ -81,7 +81,7 @@ private:
     SGBucket bucket;
 
     // clipped polygons (gpc format)
-    FGPolyList clipped_polys;
+    TGPolyList clipped_polys;
 
     // raw node list (after triangulation)
     TGTriNodes tri_nodes;
@@ -111,10 +111,10 @@ private:
 public:
 
     // Constructor
-    FGConstruct();
+    TGConstruct();
 
     // Destructor
-    ~FGConstruct();
+    ~TGConstruct();
     
     // minimum interior angle for triangulation
     inline string get_angle() const { return angle; }
@@ -145,8 +145,8 @@ public:
     inline void set_bucket( const SGBucket b ) { bucket = b; } 
 
     // clipped polygons
-    inline FGPolyList get_clipped_polys() const { return clipped_polys; }
-    inline void set_clipped_polys( FGPolyList p ) { clipped_polys = p; }
+    inline TGPolyList get_clipped_polys() const { return clipped_polys; }
+    inline void set_clipped_polys( TGPolyList p ) { clipped_polys = p; }
 
     // node list (after triangulation)
     inline TGTriNodes get_tri_nodes() const { return tri_nodes; }
diff --git a/src/BuildTiles/Main/main.cxx b/src/BuildTiles/Main/main.cxx
index a9273bc1..77054b7e 100644
--- a/src/BuildTiles/Main/main.cxx
+++ b/src/BuildTiles/Main/main.cxx
@@ -133,8 +133,8 @@ static AreaType translateUSGSCover (int usgs_value)
 
 // Scan a directory and load polygon files.
 static int actual_load_polys( const string& dir,
-			      FGConstruct& c,
-			      FGClipper& clipper ) {
+			      TGConstruct& c,
+			      TGClipper& clipper ) {
     int counter = 0;
     string base = c.get_bucket().gen_base_path();
     string tile_str = c.get_bucket().gen_index_str();
@@ -288,15 +288,15 @@ static void make_area( const LandCover &cover, TGPolygon *polys,
 
 // Generate polygons from la and-cover raster.  Horizontally- or
 // vertically-adjacent polygons will be merged automatically.
-static int actual_load_landcover ( FGConstruct & c,
-				   FGClipper &clipper ) {
+static int actual_load_landcover ( TGConstruct & c,
+				   TGClipper &clipper ) {
 
     int count = 0;
 
     try {
 
         LandCover cover(c.get_cover());
-        TGPolygon polys[FG_MAX_AREA_TYPES];
+        TGPolygon polys[TG_MAX_AREA_TYPES];
         TGPolygon poly;		// working polygon
 
         double dx = 1.0 / 120.0;
@@ -350,7 +350,7 @@ static int actual_load_landcover ( FGConstruct & c,
         // Now that we're finished looking up land cover, we have a list
         // of lists of polygons, one (possibly-empty) list for each area
         // type.  Add the remaining polygons to the clipper.
-        for ( int i = 0; i < FG_MAX_AREA_TYPES; i++ ) {
+        for ( int i = 0; i < TG_MAX_AREA_TYPES; i++ ) {
             if ( polys[i].contours() ) {
                 clipper.add_poly( i, polys[i] );
                 count++;
@@ -368,8 +368,8 @@ static int actual_load_landcover ( FGConstruct & c,
 
 // load all 2d polygons from the specified load disk directories and
 // clip against each other to resolve any overlaps
-static int load_polys( FGConstruct& c ) {
-    FGClipper clipper;
+static int load_polys( TGConstruct& c ) {
+    TGClipper clipper;
     int i;
 
     string base = c.get_bucket().gen_base_path();
@@ -411,7 +411,7 @@ static int load_polys( FGConstruct& c ) {
 
 // Load elevation data from an Array file, a regular grid of elevation
 // data) and return list of fitted nodes.
-static bool load_array( FGConstruct& c, TGArray& array) {
+static bool load_array( TGConstruct& c, TGArray& array) {
     point_list result;
     string base = c.get_bucket().gen_base_path();
     int i;
@@ -436,21 +436,15 @@ static bool load_array( FGConstruct& c, TGArray& array) {
 }
 
 
-// fit array nodes, return number of fitted nodes
-static int fit_array(TGArray& array, int error) {
-    return array.fit( error );
-}
-
-
 // triangulate the data for each polygon ( first time before splitting )
-static void first_triangulate( FGConstruct& c, const TGArray& array,
-			       FGTriangle& t ) {
+static void first_triangulate( TGConstruct& c, const TGArray& array,
+			       TGTriangle& t ) {
     // first we need to consolidate the points of the Array fit list and
     // all the polygons into a more "Triangle" friendly format
 
     point_list corner_list = array.get_corner_node_list();
     point_list fit_list = array.get_fit_node_list();
-    FGPolyList gpc_polys = c.get_clipped_polys();
+    TGPolyList gpc_polys = c.get_clipped_polys();
 
     cout << "ready to build node list and polygons" << endl;
     t.build( corner_list, fit_list, gpc_polys );
@@ -464,7 +458,7 @@ static void first_triangulate( FGConstruct& c, const TGArray& array,
 
 // triangulate the data for each polygon ( second time after splitting
 // and reassembling )
-static void second_triangulate( FGConstruct& c, FGTriangle& t ) {
+static void second_triangulate( TGConstruct& c, TGTriangle& t ) {
     t.rebuild( c );
     cout << "done re building node list and polygons" << endl;
 
@@ -490,7 +484,8 @@ static double distance2D( const Point3D p1, const Point3D p2 ) {
 
 
 // fix the elevations of the geodetic nodes
-static void fix_point_heights( FGConstruct& c, const TGArray& array ) {
+static void fix_point_heights( TGConstruct& c, const TGArray& array )
+{
     int i;
     double z;
 
@@ -509,7 +504,7 @@ static void fix_point_heights( FGConstruct& c, const TGArray& array ) {
     cout << "flattening ocean connected nodes" << endl;
 
     triele_list tris = c.get_tri_elements();
-    FGTriEle t;
+    TGTriEle t;
     Point3D p;
     AreaType a;
     int n1, n2, n3;
@@ -591,7 +586,7 @@ static void fix_point_heights( FGConstruct& c, const TGArray& array ) {
 
 
 // build the wgs-84 point list
-static void build_wgs_84_point_list( FGConstruct& c, const TGArray& array ) {
+static void build_wgs_84_point_list( TGConstruct& c, const TGArray& array ) {
     point_list geod_nodes;
     point_list wgs84_nodes;
     int i;
@@ -624,7 +619,7 @@ static void build_wgs_84_point_list( FGConstruct& c, const TGArray& array ) {
 // build the node -> element (triangle) reverse lookup table.  there
 // is an entry for each point containing a list of all the triangles
 // that share that point.
-static belongs_to_list gen_node_ele_lookup_table( FGConstruct& c ) {
+static belongs_to_list gen_node_ele_lookup_table( TGConstruct& c ) {
     belongs_to_list reverse_ele_lookup;
     reverse_ele_lookup.clear();
 
@@ -657,7 +652,7 @@ static belongs_to_list gen_node_ele_lookup_table( FGConstruct& c ) {
 
 
 // caclulate the area for the specified triangle face
-static double tri_ele_area( const FGConstruct& c, const FGTriEle tri ) {
+static double tri_ele_area( const TGConstruct& c, const TGTriEle tri ) {
     point_list nodes = c.get_geod_nodes();
 
     Point3D p1 = nodes[ tri.get_n1() ];
@@ -669,7 +664,7 @@ static double tri_ele_area( const FGConstruct& c, const FGTriEle tri ) {
 
 
 // caclulate the normal for the specified triangle face
-static Point3D calc_normal( FGConstruct& c, int i ) {
+static Point3D calc_normal( TGConstruct& c, int i ) {
     sgVec3 v1, v2, normal;
 
     point_list wgs84_nodes = c.get_wgs84_nodes();
@@ -731,7 +726,7 @@ static Point3D calc_normal( FGConstruct& c, int i ) {
 
 
 // build the face normal list
-static point_list gen_face_normals( FGConstruct& c ) {
+static point_list gen_face_normals( TGConstruct& c ) {
     point_list face_normals;
 
     // traverse triangle structure building the face normal table
@@ -750,7 +745,7 @@ static point_list gen_face_normals( FGConstruct& c ) {
 
 
 // calculate the normals for each point in wgs84_nodes
-static point_list gen_point_normals( FGConstruct& c ) {
+static point_list gen_point_normals( TGConstruct& c ) {
     point_list point_normals;
 
     Point3D normal;
@@ -793,14 +788,14 @@ static point_list gen_point_normals( FGConstruct& c ) {
 
 
 // generate the flight gear scenery file
-static void do_output( FGConstruct& c, FGGenOutput& output ) {
+static void do_output( TGConstruct& c, TGGenOutput& output ) {
     output.build( c );
     output.write( c );
 }
 
 
 // collect custom objects and move to scenery area
-static void do_custom_objects( const FGConstruct& c ) {
+static void do_custom_objects( const TGConstruct& c ) {
     SGBucket b = c.get_bucket();
 
     // Create/open the output .stg file for writing
@@ -854,7 +849,7 @@ static void do_custom_objects( const FGConstruct& c ) {
 }
 
 // master construction routine
-static void construct_tile( FGConstruct& c ) {
+static void construct_tile( TGConstruct& c ) {
     cout << "Construct tile, bucket = " << c.get_bucket() << endl;
 
     // fit with ever increasing error tolerance until we produce <=
@@ -879,7 +874,7 @@ static void construct_tile( FGConstruct& c ) {
     TGArray array;
     load_array( c, array );
 
-    FGTriangle t;
+    TGTriangle t;
 
     while ( ! acceptable ) {
 	// do a least squares fit of the (array) data with the given
@@ -965,7 +960,7 @@ static void construct_tile( FGConstruct& c ) {
 
     // match tile edges with any neighbor tiles that have already been
     // generated
-    FGMatch m;
+    TGMatch m;
     m.load_neighbor_shared( c );
     m.split_tile( c );
     m.write_shared( c );
@@ -999,7 +994,7 @@ static void construct_tile( FGConstruct& c ) {
     build_wgs_84_point_list( c, array );
 
     // generate the output
-    FGGenOutput output;
+    TGGenOutput output;
     do_output( c, output );
 
     array.close();
@@ -1124,7 +1119,7 @@ int main(int argc, char **argv) {
 #endif  // end of stuff that crashes Cygwin
 
     // main construction data management class
-    FGConstruct c;
+    TGConstruct c;
 
     c.set_angle( min_angle );
     c.set_cover( cover );
@@ -1133,7 +1128,7 @@ int main(int argc, char **argv) {
     c.set_useUKGrid( useUKgrid );
 
     c.set_min_nodes( 50 );
-    c.set_max_nodes( (int)(FG_MAX_NODES * 0.8) );
+    c.set_max_nodes( (int)(TG_MAX_NODES * 0.8) );
 
     if (tile_id == -1) {
 	if (xdist == -1 || ydist == -1) {
diff --git a/src/BuildTiles/Match/match.cxx b/src/BuildTiles/Match/match.cxx
index d5a623e4..76d6dee0 100644
--- a/src/BuildTiles/Match/match.cxx
+++ b/src/BuildTiles/Match/match.cxx
@@ -40,16 +40,16 @@ SG_USING_STD(cout);
 SG_USING_STD(endl);
 
 
-FGMatch::FGMatch( void ) {
+TGMatch::TGMatch( void ) {
 }
 
 
-FGMatch::~FGMatch( void ) {
+TGMatch::~TGMatch( void ) {
 }
 
 
 // scan the specified share file for the specified information
-void FGMatch::scan_share_file( const string& dir, const SGBucket& b, 
+void TGMatch::scan_share_file( const string& dir, const SGBucket& b, 
 			       neighbor_type search, neighbor_type dest )
 {
     string file = dir + "/"  + b.gen_base_path() + "/" + b.gen_index_str();
@@ -140,7 +140,7 @@ void FGMatch::scan_share_file( const string& dir, const SGBucket& b,
 
 
 // try to find info for the specified shared component
-void FGMatch::load_shared( const FGConstruct& c, neighbor_type n ) {
+void TGMatch::load_shared( const TGConstruct& c, neighbor_type n ) {
     SGBucket b = c.get_bucket();
 
     double clon = b.get_center_lon();
@@ -204,7 +204,7 @@ void FGMatch::load_shared( const FGConstruct& c, neighbor_type n ) {
 
 // load any previously existing shared data from all neighbors (if
 // shared data for a component exists set that components flag to true
-void FGMatch::load_neighbor_shared( FGConstruct& c ) {
+void TGMatch::load_neighbor_shared( TGConstruct& c ) {
     cout << "Loading existing shared data from neighbor tiles" << endl;
 
     // start with all flags false
@@ -289,7 +289,7 @@ Point3D tgFakeNormal( const Point3D& p ) {
 // segments and the body.  This must be done after calling
 // load_neighbor_data() and will ignore any shared data from the
 // current tile that already exists from a neighbor.
-void FGMatch::split_tile( FGConstruct& c ) {
+void TGMatch::split_tile( TGConstruct& c ) {
     int i;
 
     cout << "Spliting tile" << endl;
@@ -456,7 +456,7 @@ void FGMatch::split_tile( FGConstruct& c ) {
 
 // write the new shared edge points, normals, and segments for this
 // tile
-void FGMatch::write_shared( FGConstruct& c ) {
+void TGMatch::write_shared( TGConstruct& c ) {
     string base = c.get_work_base();
     SGBucket b = c.get_bucket();
 
@@ -635,7 +635,7 @@ void insert_normal( point_list& normals, Point3D n, int i ) {
 
 // reassemble the tile pieces (combining the shared data and our own
 // data)
-void FGMatch::assemble_tile( FGConstruct& c ) {
+void TGMatch::assemble_tile( TGConstruct& c ) {
     int i;
     TGTriNodes new_nodes;
     new_nodes.clear();
diff --git a/src/BuildTiles/Match/match.hxx b/src/BuildTiles/Match/match.hxx
index 8cc5aa5f..700f6333 100644
--- a/src/BuildTiles/Match/match.hxx
+++ b/src/BuildTiles/Match/match.hxx
@@ -37,7 +37,7 @@
 #include <Main/construct.hxx>
 
 
-class FGMatch {
+class TGMatch {
 
 private:
 
@@ -73,36 +73,36 @@ public:
     };
 
     // Constructor
-    FGMatch( void );
+    TGMatch( void );
 
     // Destructor
-    ~FGMatch( void );
+    ~TGMatch( void );
 
     // load any previously existing shared data from all neighbors (if
     // shared data for a component exists set that components flag to
     // true
-    void load_neighbor_shared( FGConstruct& c );
+    void load_neighbor_shared( TGConstruct& c );
 
     // scan the specified share file for the specified information
     void scan_share_file( const string& dir, const SGBucket& b,
 			  neighbor_type search, neighbor_type dest );
 
     // try to find info for the specified shared component
-    void load_shared( const FGConstruct& c, neighbor_type n );
+    void load_shared( const TGConstruct& c, neighbor_type n );
 
     // split up the tile between the shared edge points, normals, and
     // segments and the body.  This must be done after calling
     // load_neighbor_data() and will ignore any shared data from the
     // current tile that already exists from a neighbor.
-    void split_tile( FGConstruct& c );
+    void split_tile( TGConstruct& c );
 
     // write the new shared edge points, normals, and segments for
     // this tile
-    void write_shared( FGConstruct& c );
+    void write_shared( TGConstruct& c );
 
     // reassemble the tile pieces (combining the shared data and our
     // own data)
-    void assemble_tile( FGConstruct& c );
+    void assemble_tile( TGConstruct& c );
 };
 
 
diff --git a/src/BuildTiles/Triangulate/triangle.cxx b/src/BuildTiles/Triangulate/triangle.cxx
index 245a0f21..1b42a01e 100644
--- a/src/BuildTiles/Triangulate/triangle.cxx
+++ b/src/BuildTiles/Triangulate/triangle.cxx
@@ -33,20 +33,20 @@ SG_USING_STD(endl);
 
 
 // Constructor
-FGTriangle::FGTriangle( void ) {
+TGTriangle::TGTriangle( void ) {
 }
 
 
 // Destructor
-FGTriangle::~FGTriangle( void ) {
+TGTriangle::~TGTriangle( void ) {
 }
 
 
 // populate this class based on the specified gpc_polys list
 int 
-FGTriangle::build( const point_list& corner_list,
+TGTriangle::build( const point_list& corner_list,
 		   const point_list& fit_list, 
-		   const FGPolyList& gpc_polys )
+		   const TGPolyList& gpc_polys )
 {
     int debug_counter = 0;
     int index;
@@ -78,7 +78,7 @@ FGTriangle::build( const point_list& corner_list,
     // process polygons in priority order
     cout << "prepairing node list and polygons" << endl;
 
-    for ( i = 0; i < FG_MAX_AREA_TYPES; ++i ) {
+    for ( i = 0; i < TG_MAX_AREA_TYPES; ++i ) {
 	polylist[i].clear();
 
 	cout << "area type = " << i << " polys = " << gpc_polys.polys[i].size() 
@@ -198,7 +198,7 @@ FGTriangle::build( const point_list& corner_list,
 	index = in_nodes.course_add( fit_list[i] );
     }
 
-    for ( i = 0; i < FG_MAX_AREA_TYPES; ++i ) {
+    for ( i = 0; i < TG_MAX_AREA_TYPES; ++i ) {
 	if ( polylist[i].size() ) {
 	    cout << get_area_name((AreaType)i) << " = " 
 		 << polylist[i].size() << endl;
@@ -214,7 +214,7 @@ FGTriangle::build( const point_list& corner_list,
     point_list node_list = in_nodes.get_node_list();
     TGPolygon poly;
 
-    for ( i = 0; i < FG_MAX_AREA_TYPES; ++i ) {
+    for ( i = 0; i < TG_MAX_AREA_TYPES; ++i ) {
 	cout << "area type = " << i << endl;
 	poly_list_iterator tp_current, tp_last;
 	tp_current = polylist[i].begin();
@@ -265,7 +265,7 @@ FGTriangle::build( const point_list& corner_list,
 
 
 // populate this class based on the specified gpc_polys list
-int FGTriangle::rebuild( FGConstruct& c ) {
+int TGTriangle::rebuild( TGConstruct& c ) {
     in_nodes.clear();
     in_segs.clear();
 
@@ -338,7 +338,7 @@ static void write_out_data(struct triangulateio *out) {
 // generates extra nodes for a better triangulation.  2 = second pass
 // after split/reassem where we don't want any extra nodes generated.
 
-int FGTriangle::run_triangulate( const string& angle, const int pass ) {
+int TGTriangle::run_triangulate( const string& angle, const int pass ) {
     TGPolygon poly;
     Point3D p;
     struct triangulateio in, out, vorout;
@@ -420,7 +420,7 @@ int FGTriangle::run_triangulate( const string& angle, const int pass ) {
 
     // region list
     in.numberofregions = 0;
-    for ( i = 0; i < FG_MAX_AREA_TYPES; ++i ) {
+    for ( i = 0; i < TG_MAX_AREA_TYPES; ++i ) {
 	poly_list_iterator h_current, h_last;
 	h_current = polylist[i].begin();
 	h_last = polylist[i].end();
@@ -436,7 +436,7 @@ int FGTriangle::run_triangulate( const string& angle, const int pass ) {
 
     in.regionlist = (REAL *) malloc(in.numberofregions * 4 * sizeof(REAL));
     counter = 0;
-    for ( i = 0; i < FG_MAX_AREA_TYPES; ++i ) {
+    for ( i = 0; i < TG_MAX_AREA_TYPES; ++i ) {
 	poly_list_iterator h_current, h_last;
 	h_current = polylist[(int)i].begin();
 	h_last = polylist[(int)i].end();
@@ -504,7 +504,7 @@ int FGTriangle::run_triangulate( const string& angle, const int pass ) {
 	tri_options = "pczYYAen";
     } else {
 	cout << "unknown pass number = " << pass 
-	     << " in FGTriangle::run_triangulate()" << endl;
+	     << " in TGTriangle::run_triangulate()" << endl;
 	exit(-1);
     }
     cout << "Triangulation with options = " << tri_options << endl;
@@ -514,7 +514,7 @@ int FGTriangle::run_triangulate( const string& angle, const int pass ) {
     // TEMPORARY
     // write_tri_data(&out);
 
-    // now copy the results back into the corresponding FGTriangle
+    // now copy the results back into the corresponding TGTriangle
     // structures
 
     // nodes
@@ -548,7 +548,7 @@ int FGTriangle::run_triangulate( const string& angle, const int pass ) {
 	}
 	// cout << "triangle = " << n1 << " " << n2 << " " << n3 << endl;
 
-	elelist.push_back( FGTriEle( n1, n2, n3, attribute ) );
+	elelist.push_back( TGTriEle( n1, n2, n3, attribute ) );
     }
 
     // free mem allocated to the "Triangle" structures
diff --git a/src/BuildTiles/Triangulate/triangle.hxx b/src/BuildTiles/Triangulate/triangle.hxx
index 398ff625..88ccdb47 100644
--- a/src/BuildTiles/Triangulate/triangle.hxx
+++ b/src/BuildTiles/Triangulate/triangle.hxx
@@ -34,7 +34,6 @@
 #include <simgear/math/point3d.hxx>
 
 #include <Array/array.hxx>
-#include <Clipper/clipper.hxx>
 #include <Main/construct.hxx>
 
 #include <Geometry/trinodes.hxx>
@@ -50,7 +49,7 @@ extern "C" {
 #include "trieles.hxx"
 
 
-class FGTriangle {
+class TGTriangle {
 
 private:
 
@@ -63,7 +62,7 @@ private:
     TGTriSegments out_segs;
 
     // polygon list
-    poly_list polylist[FG_MAX_AREA_TYPES];
+    poly_list polylist[TG_MAX_AREA_TYPES];
     
     // triangle list
     triele_list elelist;
@@ -71,8 +70,8 @@ private:
 public:
 
     // Constructor and destructor
-    FGTriangle( void );
-    ~FGTriangle( void );
+    TGTriangle( void );
+    ~TGTriangle( void );
 
     // add nodes from the dem fit
     int add_nodes();
@@ -80,10 +79,10 @@ public:
     // populate this class based on the specified gpc_polys list
     int build( const point_list& corner_list, 
 	       const point_list& fit_list,
-	       const FGPolyList& gpc_polys );
+	       const TGPolyList& gpc_polys );
 
     // populate this class based on the specified gpc_polys list
-    int rebuild( FGConstruct& c );
+    int rebuild( TGConstruct& c );
 
     // Front end triangulator for polygon list.  Allocates and builds
     // up all the needed structures for the triangulator, runs it,
diff --git a/src/BuildTiles/Triangulate/trieles.hxx b/src/BuildTiles/Triangulate/trieles.hxx
index 7ac2d6f3..602bcc02 100644
--- a/src/BuildTiles/Triangulate/trieles.hxx
+++ b/src/BuildTiles/Triangulate/trieles.hxx
@@ -38,7 +38,7 @@ SG_USING_STD(vector);
 
 
 // a segment is two integer pointers into the node list
-class FGTriEle {
+class TGTriEle {
     int n1, n2, n3;
 
     double attribute;
@@ -46,12 +46,12 @@ class FGTriEle {
 public:
 
     // Constructor and destructor
-    inline FGTriEle( void ) { };
-    inline FGTriEle( int i1, int i2, int i3, double a ) {
+    inline TGTriEle( void ) { };
+    inline TGTriEle( int i1, int i2, int i3, double a ) {
 	n1 = i1; n2 = i2; n3 = i3; attribute = a;
     }
 
-    inline ~FGTriEle( void ) { };
+    inline ~TGTriEle( void ) { };
 
     inline int get_n1() const { return n1; }
     inline void set_n1( int i ) { n1 = i; }
@@ -65,7 +65,7 @@ public:
 };
 
 
-typedef vector < FGTriEle > triele_list;
+typedef vector < TGTriEle > triele_list;
 typedef triele_list::iterator triele_list_iterator;
 typedef triele_list::const_iterator const_triele_list_iterator;
 
diff --git a/src/Lib/Geometry/poly_support.cxx b/src/Lib/Geometry/poly_support.cxx
index 9f62955b..f5e42960 100644
--- a/src/Lib/Geometry/poly_support.cxx
+++ b/src/Lib/Geometry/poly_support.cxx
@@ -382,7 +382,7 @@ void polygon_tesselate( const TGPolygon &p,
     // TEMPORARY
     // write_tri_data(&out);
 
-    // now copy the results back into the corresponding FGTriangle
+    // now copy the results back into the corresponding TGTriangle
     // structures
 
     // triangles
@@ -400,7 +400,7 @@ void polygon_tesselate( const TGPolygon &p,
 	}
 	// cout << "triangle = " << n1 << " " << n2 << " " << n3 << endl;
 
-	elelist.push_back( FGTriEle( n1, n2, n3, attribute ) );
+	elelist.push_back( TGTriEle( n1, n2, n3, attribute ) );
     }
 
     // output points
@@ -468,7 +468,7 @@ TGPolygon polygon_tesselate_alt( TGPolygon &p ) {
     // 3.  Convert the tesselated output to a list of tringles.
     //     basically a polygon with a contour for every triangle
     for ( i = 0; i < (int)trieles.size(); ++i ) {
-	FGTriEle t = trieles[i];
+	TGTriEle t = trieles[i];
 	Point3D p1 = nodes[ t.get_n1() ];
 	Point3D p2 = nodes[ t.get_n2() ];
 	Point3D p3 = nodes[ t.get_n3() ];
@@ -515,7 +515,7 @@ static void contour_tesselate( TGContourNode *node, const TGPolygon &p,
 	out_pts.push_back( Point3D(0, 0, 0) );
 	out_pts.push_back( Point3D(0, 1, 0) );
 	out_pts.push_back( Point3D(1, 1, 0) );
-	elelist.push_back( FGTriEle( 0, 1, 2, 0.0 ) );
+	elelist.push_back( TGTriEle( 0, 1, 2, 0.0 ) );
 	return;
     }
 #endif
@@ -661,7 +661,7 @@ static void contour_tesselate( TGContourNode *node, const TGPolygon &p,
     // TEMPORARY
     // write_tri_data(&out);
 
-    // now copy the results back into the corresponding FGTriangle
+    // now copy the results back into the corresponding TGTriangle
     // structures
 
     // triangles
@@ -679,7 +679,7 @@ static void contour_tesselate( TGContourNode *node, const TGPolygon &p,
 	}
 	// cout << "triangle = " << n1 << " " << n2 << " " << n3 << endl;
 
-	elelist.push_back( FGTriEle( n1, n2, n3, attribute ) );
+	elelist.push_back( TGTriEle( n1, n2, n3, attribute ) );
     }
 
     // output points
@@ -728,7 +728,7 @@ static Point3D point_inside_hole( point_list contour ) {
 	exit(-1);
     }
 
-    FGTriEle t = elelist[0];
+    TGTriEle t = elelist[0];
     Point3D p1 = contour[ t.get_n1() ];
     Point3D p2 = contour[ t.get_n2() ];
     Point3D p3 = contour[ t.get_n3() ];
@@ -778,7 +778,7 @@ static Point3D point_inside_contour( TGContourNode *node, const TGPolygon &p ) {
     double max_area = 0.0;
     int biggest = 0;
     for ( i = 0; i < (int)elelist.size(); ++i ) {
-	FGTriEle t = elelist[i];
+	TGTriEle t = elelist[i];
 	Point3D p1 = out_pts[ t.get_n1() ];
 	Point3D p2 = out_pts[ t.get_n2() ];
 	Point3D p3 = out_pts[ t.get_n3() ];
@@ -791,7 +791,7 @@ static Point3D point_inside_contour( TGContourNode *node, const TGPolygon &p ) {
 
     // find center point of largest triangle
     cout << "biggest = " << biggest + 1 << " out of " << elelist.size() << endl;
-    FGTriEle t = elelist[biggest];
+    TGTriEle t = elelist[biggest];
     contour_num = node->get_contour_num();
     Point3D p1 = out_pts[ t.get_n1() ];
     Point3D p2 = out_pts[ t.get_n2() ];
diff --git a/src/Lib/Geometry/trinodes.cxx b/src/Lib/Geometry/trinodes.cxx
index b5a7b1af..0d0ea450 100644
--- a/src/Lib/Geometry/trinodes.cxx
+++ b/src/Lib/Geometry/trinodes.cxx
@@ -40,7 +40,7 @@ int TGTriNodes::unique_add( const Point3D& p ) {
     point_list_iterator current, last;
     int counter = 0;
 
-    // cout << p.x() << "," << p.y() << endl;
+    cout << "unique add = " << p << endl;
 
     // see if point already exists
     current = node_list.begin();
@@ -48,6 +48,12 @@ int TGTriNodes::unique_add( const Point3D& p ) {
     for ( ; current != last; ++current ) {
 	if ( close_enough_2d(p, *current) ) {
 	    // cout << "found an existing match!" << endl;
+
+            // update elevation if new point has better info
+            if ( p.z() > current->z() ) {
+                current->setz( p.z() );
+            }
+
 	    return counter;
 	}
 	
@@ -112,6 +118,12 @@ int TGTriNodes::course_add( const Point3D& p ) {
     for ( ; current != last; ++current ) {
 	if ( course_close_enough(p, *current) ) {
 	    // cout << "found an existing match!" << endl;
+
+            // update elevation if new point has better info
+            if ( p.z() > current->z() ) {
+                current->setz( p.z() );
+            }
+
 	    return counter;
 	}
 	
diff --git a/src/Lib/Optimize/genfans.cxx b/src/Lib/Optimize/genfans.cxx
index 51eb7fc3..39892e31 100644
--- a/src/Lib/Optimize/genfans.cxx
+++ b/src/Lib/Optimize/genfans.cxx
@@ -54,14 +54,14 @@ static void add_and_expand( opt_list& by_node, int n, int i ) {
 
 // given an input triangle, shuffle nodes so that "center" is the
 // first node, but maintain winding order.
-static FGTriEle canonify( const FGTriEle& t, int center ) {
+static TGTriEle canonify( const TGTriEle& t, int center ) {
     if ( t.get_n1() == center ) {
 	// already ok
 	return t;
     } else if ( t.get_n2() == center ) {
-	return FGTriEle( t.get_n2(), t.get_n3(), t.get_n1(), 0.0 );
+	return TGTriEle( t.get_n2(), t.get_n3(), t.get_n1(), 0.0 );
     } else if ( t.get_n3() == center ) {
-	return FGTriEle( t.get_n3(), t.get_n1(), t.get_n2(), 0.0 );
+	return TGTriEle( t.get_n3(), t.get_n1(), t.get_n2(), 0.0 );
     } else {
 	cout << "ERROR, index doesn't refer to this triangle!!!" << endl;
 	exit(-1);
@@ -86,8 +86,8 @@ static int_list make_best_fan( const triele_list& master_tris,
 	int_list tmp_result;
 	tmp_result.clear();
 
-	FGTriEle current_tri;
-	FGTriEle test;
+	TGTriEle current_tri;
+	TGTriEle test;
 	current_tri = canonify( master_tris[local_tris[start]], center );
 	tmp_result.push_back( local_tris[start] );
 
@@ -200,7 +200,7 @@ opt_list TGGenFans::greedy_build( triele_list tris ) {
 	int_list_iterator i_current = i_start;
 	int_list_iterator i_last = best_fan.end();
 	for ( ; i_current != i_last; ++i_current ) {
-	    FGTriEle t = canonify( tris[*i_current], index );
+	    TGTriEle t = canonify( tris[*i_current], index );
 	    if ( i_start == i_current ) {
 		node_list.push_back( t.get_n1() );
 		node_list.push_back( t.get_n2() );