From 4dea9807f6e4f242af72f6fda2a45a187a059bdc Mon Sep 17 00:00:00 2001
From: timoore <timoore>
Date: Wed, 14 May 2008 22:10:07 +0000
Subject: [PATCH] fg: move most scenery-related code to simgear

From Till Busch.
---
 projects/VC7.1/FlightGear.vcproj |  12 -
 src/Main/renderer.cxx            |   1 -
 src/Scenery/Makefile.am          |   2 -
 src/Scenery/SceneryPager.cxx     |   5 +-
 src/Scenery/SceneryPager.hxx     |  24 +-
 src/Scenery/newcache.cxx         | 191 ----------
 src/Scenery/newcache.hxx         | 142 --------
 src/Scenery/tileentry.cxx        | 592 -------------------------------
 src/Scenery/tileentry.hxx        | 215 -----------
 src/Scenery/tilemgr.cxx          |  91 +++--
 src/Scenery/tilemgr.hxx          |  36 +-
 11 files changed, 75 insertions(+), 1236 deletions(-)
 delete mode 100644 src/Scenery/newcache.cxx
 delete mode 100644 src/Scenery/newcache.hxx
 delete mode 100644 src/Scenery/tileentry.cxx
 delete mode 100644 src/Scenery/tileentry.hxx

diff --git a/projects/VC7.1/FlightGear.vcproj b/projects/VC7.1/FlightGear.vcproj
index 7c9a80c14..be611d366 100755
--- a/projects/VC7.1/FlightGear.vcproj
+++ b/projects/VC7.1/FlightGear.vcproj
@@ -2133,12 +2133,6 @@
 		<Filter
 			Name="Lib_Scenery"
 			Filter="">
-			<File
-				RelativePath="..\..\src\Scenery\newcache.cxx">
-			</File>
-			<File
-				RelativePath="..\..\src\Scenery\newcache.hxx">
-			</File>
 			<File
 				RelativePath="..\..\src\Scenery\redout.cxx">
 			</File>
@@ -2157,12 +2151,6 @@
 			<File
 				RelativePath="..\..\src\Scenery\SceneryPager.hxx">
 			</File>
-			<File
-				RelativePath="..\..\src\Scenery\tileentry.cxx">
-			</File>
-			<File
-				RelativePath="..\..\src\Scenery\tileentry.hxx">
-			</File>
 			<File
 				RelativePath="..\..\src\Scenery\tilemgr.cxx">
 			</File>
diff --git a/src/Main/renderer.cxx b/src/Main/renderer.cxx
index e41703224..ed715a9d2 100644
--- a/src/Main/renderer.cxx
+++ b/src/Main/renderer.cxx
@@ -81,7 +81,6 @@
 
 #include <simgear/environment/visual_enviro.hxx>
 
-#include <Scenery/tileentry.hxx>
 #include <Time/light.hxx>
 #include <Time/light.hxx>
 #include <Aircraft/aircraft.hxx>
diff --git a/src/Scenery/Makefile.am b/src/Scenery/Makefile.am
index 558db4a9b..041e5cdb5 100644
--- a/src/Scenery/Makefile.am
+++ b/src/Scenery/Makefile.am
@@ -1,11 +1,9 @@
 noinst_LIBRARIES = libScenery.a
 
 libScenery_a_SOURCES = \
-	newcache.cxx newcache.hxx \
 	redout.cxx redout.hxx \
 	scenery.cxx scenery.hxx \
 	SceneryPager.cxx SceneryPager.hxx \
-	tileentry.cxx tileentry.hxx \
 	tilemgr.cxx tilemgr.hxx
 
 INCLUDES = -I$(top_srcdir) -I$(top_srcdir)/src
diff --git a/src/Scenery/SceneryPager.cxx b/src/Scenery/SceneryPager.cxx
index c72ffe470..690cd9395 100644
--- a/src/Scenery/SceneryPager.cxx
+++ b/src/Scenery/SceneryPager.cxx
@@ -52,10 +52,11 @@ void SceneryPager::requestNodeFile(const std::string& fileName,osg::Group* group
 }
 
 void SceneryPager::queueRequest(const std::string& fileName, osg::Group* group,
-                                float priority, osg::FrameStamp* frameStamp)
+                                float priority, osg::FrameStamp* frameStamp,
+                                osgDB::ReaderWriter::Options* options)
 {
     _pagerRequests.push_back(PagerRequest(fileName, group, priority,
-                                          frameStamp));
+                                          frameStamp, options));
 }
 
 void SceneryPager::queueDeleteRequest(osg::ref_ptr<osg::Object>& objptr)
diff --git a/src/Scenery/SceneryPager.hxx b/src/Scenery/SceneryPager.hxx
index 283c9db95..5ec53372c 100644
--- a/src/Scenery/SceneryPager.hxx
+++ b/src/Scenery/SceneryPager.hxx
@@ -38,8 +38,16 @@ public:
     virtual void requestNodeFile(const std::string& fileName,osg::Group* group,
                                  float priority, const osg::FrameStamp* framestamp);
 
+    virtual void requestNodeFile(const std::string& fileName,osg::Group* group,
+                                 float priority, const osg::FrameStamp* framestamp,
+                                 osgDB::ReaderWriter::Options* options) {
+        osgDB::DatabasePager::requestNodeFile(fileName, group, priority,
+                                              framestamp, options);
+    }
+
     void queueRequest(const std::string& fileName, osg::Group* node,
-                      float priority, osg::FrameStamp* frameStamp);
+                      float priority, osg::FrameStamp* frameStamp,
+                      osgDB::ReaderWriter::Options* options);
     // This is passed a ref_ptr so that it can "take ownership" of the
     // node to delete and decrement its refcount while holding the
     // lock on the delete list.
@@ -52,21 +60,27 @@ protected:
         PagerRequest() {}
         PagerRequest(const PagerRequest& rhs) :
             _fileName(rhs._fileName), _group(rhs._group),
-            _priority(rhs._priority), _frameStamp(rhs._frameStamp) {}
+            _priority(rhs._priority), _frameStamp(rhs._frameStamp),
+            _options(rhs._options) {}
+
         PagerRequest(const std::string& fileName, osg::Group* group,
-                     float priority, osg::FrameStamp* frameStamp) :
+                     float priority, osg::FrameStamp* frameStamp,
+                     osgDB::ReaderWriter::Options* options):
             _fileName(fileName), _group(group), _priority(priority),
-            _frameStamp(frameStamp) {}
+            _frameStamp(frameStamp), _options(options) {}
+
         void doRequest(SceneryPager* pager)
         {
             if (_group->getNumChildren() == 0)
                 pager->requestNodeFile(_fileName, _group.get(), _priority,
-                                       _frameStamp.get());
+                                       _frameStamp.get(), _options.get());
         }
+
         std::string _fileName;
         osg::ref_ptr<osg::Group> _group;
         float _priority;
         osg::ref_ptr<osg::FrameStamp> _frameStamp;
+        osg::ref_ptr<osgDB::ReaderWriter::Options> _options;
     };
     typedef std::vector<PagerRequest> PagerRequestList;
     PagerRequestList _pagerRequests;
diff --git a/src/Scenery/newcache.cxx b/src/Scenery/newcache.cxx
deleted file mode 100644
index d17328a62..000000000
--- a/src/Scenery/newcache.cxx
+++ /dev/null
@@ -1,191 +0,0 @@
-// newcache.cxx -- routines to handle scenery tile caching
-//
-// Written by Curtis Olson, started December 2000.
-//
-// Copyright (C) 2000  Curtis L. Olson  - http://www.flightgear.org/~curt
-//
-// This program is free software; you can redistribute it and/or
-// modify it under the terms of the GNU General Public License as
-// published by the Free Software Foundation; either version 2 of the
-// License, or (at your option) any later version.
-//
-// This program is distributed in the hope that it will be useful, but
-// WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-// General Public License for more details.
-//
-// You should have received a copy of the GNU General Public License
-// along with this program; if not, write to the Free Software
-// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
-//
-// $Id$
-
-
-#ifdef HAVE_CONFIG_H
-#  include <config.h>
-#endif
-
-#include <simgear/bucket/newbucket.hxx>
-#include <simgear/debug/logstream.hxx>
-#include <simgear/misc/sg_path.hxx>
-
-#include <Main/globals.hxx>
-#include <Main/viewer.hxx>
-#include <Scenery/scenery.hxx>  // for scenery.center
-
-#include "newcache.hxx"
-#include "tileentry.hxx"
-
-
-SG_USING_NAMESPACE(std);
-
-
-// Constructor
-FGNewCache::FGNewCache( void ) :
-    max_cache_size(100)
-{
-    tile_cache.clear();
-}
-
-
-// Destructor
-FGNewCache::~FGNewCache( void ) {
-    clear_cache();
-}
-
-
-// Free a tile cache entry
-void FGNewCache::entry_free( long cache_index ) {
-    SG_LOG( SG_TERRAIN, SG_DEBUG, "FREEING CACHE ENTRY = " << cache_index );
-    FGTileEntry *tile = tile_cache[cache_index];
-    tile->disconnect_ssg_nodes();
-
-#ifdef WISH_PLIB_WAS_THREADED // but it isn't
-    tile->sched_removal();
-#else
-    tile->free_tile();
-    delete tile;
-#endif
-
-    tile_cache.erase( cache_index );
-}
-
-
-// Initialize the tile cache subsystem
-void FGNewCache::init( void ) {
-    SG_LOG( SG_TERRAIN, SG_INFO, "Initializing the tile cache." );
-
-    SG_LOG( SG_TERRAIN, SG_INFO, "  max cache size = " 
-	    << max_cache_size );
-    SG_LOG( SG_TERRAIN, SG_INFO, "  current cache size = " 
-	    << tile_cache.size() );
-
-#if 0 // don't clear the cache
-    clear_cache();
-#endif
-
-    SG_LOG( SG_TERRAIN, SG_INFO, "  done with init()"  );
-}
-
-
-// Search for the specified "bucket" in the cache
-bool FGNewCache::exists( const SGBucket& b ) const {
-    long tile_index = b.gen_index();
-    const_tile_map_iterator it = tile_cache.find( tile_index );
-
-    return ( it != tile_cache.end() );
-}
-
-// Return the index of the oldest tile in the cache, return -1 if
-// nothing available to be removed.
-long FGNewCache::get_oldest_tile() {
-    // we need to free the furthest entry
-    long min_index = -1;
-    double timestamp = 0.0;
-    double min_time = DBL_MAX;
-
-    tile_map_iterator current = tile_cache.begin();
-    tile_map_iterator end = tile_cache.end();
-    
-    for ( ; current != end; ++current ) {
-        long index = current->first;
-        FGTileEntry *e = current->second;
-        if ( e->is_loaded() ) {
-            
-            timestamp = e->get_timestamp();
-            if ( timestamp < min_time ) {
-                min_time = timestamp;
-                min_index = index;
-            }
-
-        } else {
-            SG_LOG( SG_TERRAIN, SG_DEBUG, "loaded = " << e->is_loaded()
-                    << " time stamp = " << e->get_timestamp() );
-        }
-    }
-
-    SG_LOG( SG_TERRAIN, SG_DEBUG, "    index = " << min_index );
-    SG_LOG( SG_TERRAIN, SG_DEBUG, "    min_time = " << min_time );
-
-    return min_index;
-}
-
-
-// Clear the inner ring flag for all tiles in the cache so that the
-// external tile scheduler can flag the inner ring correctly.
-void FGNewCache::clear_inner_ring_flags() {
-    tile_map_iterator current = tile_cache.begin();
-    tile_map_iterator end = tile_cache.end();
-    
-    for ( ; current != end; ++current ) {
-        FGTileEntry *e = current->second;
-        if ( e->is_loaded() ) {
-            e->set_inner_ring( false );
-        }
-    }
-}
-
-// Clear a cache entry, note that the cache only holds pointers
-// and this does not free the object which is pointed to.
-void FGNewCache::clear_entry( long cache_index ) {
-    tile_cache.erase( cache_index );
-}
-
-
-// Clear all completely loaded tiles (ignores partially loaded tiles)
-void FGNewCache::clear_cache() {
-    std::vector<long> indexList;
-    tile_map_iterator current = tile_cache.begin();
-    tile_map_iterator end = tile_cache.end();
-    
-    for ( ; current != end; ++current ) {
-	long index = current->first;
-	SG_LOG( SG_TERRAIN, SG_DEBUG, "clearing " << index );
-	FGTileEntry *e = current->second;
-        if ( e->is_loaded() ) {
-            e->tile_bucket.make_bad();
-	    // entry_free modifies tile_cache, so store index and call entry_free() later;
-	    indexList.push_back( index);
-        }
-    }
-    for (unsigned int it = 0; it < indexList.size(); it++) {
-	entry_free( indexList[ it]);
-    }
-    // and ... just in case we missed something ... 
-    osg::Group* group = globals->get_scenery()->get_terrain_branch();
-    group->removeChildren(0, group->getNumChildren());
-}
-
-
-/**
- * Create a new tile and schedule it for loading.
- */
-bool FGNewCache::insert_tile( FGTileEntry *e ) {
-    // register tile in the cache
-    long tile_index = e->get_tile_bucket().gen_index();
-    tile_cache[tile_index] = e;
-
-    return true;
-}
-
-
diff --git a/src/Scenery/newcache.hxx b/src/Scenery/newcache.hxx
deleted file mode 100644
index 78a3eb6eb..000000000
--- a/src/Scenery/newcache.hxx
+++ /dev/null
@@ -1,142 +0,0 @@
-// newcache.hxx -- routines to handle scenery tile caching
-//
-// Written by Curtis Olson, started December 2000.
-//
-// Copyright (C) 2000  Curtis L. Olson  - http://www.flightgear.org/~curt
-//
-// This program is free software; you can redistribute it and/or
-// modify it under the terms of the GNU General Public License as
-// published by the Free Software Foundation; either version 2 of the
-// License, or (at your option) any later version.
-//
-// This program is distributed in the hope that it will be useful, but
-// WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-// General Public License for more details.
-//
-// You should have received a copy of the GNU General Public License
-// along with this program; if not, write to the Free Software
-// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
-//
-// $Id$
-
-
-#ifndef _NEWCACHE_HXX
-#define _NEWCACHE_HXX
-
-
-#ifndef __cplusplus                                                          
-# error This library requires C++
-#endif                                   
-
-
-#ifdef HAVE_CONFIG_H
-#  include <config.h>
-#endif
-
-#include <map>
-
-#include <simgear/bucket/newbucket.hxx>
-#include <simgear/math/point3d.hxx>
-
-#include "tileentry.hxx"
-
-SG_USING_STD(map);
-
-// A class to store and manage a pile of tiles
-class FGNewCache {
-public:
-    typedef map < long, FGTileEntry * > tile_map;
-    typedef tile_map::iterator tile_map_iterator;
-    typedef tile_map::const_iterator const_tile_map_iterator;
-private:
-    // cache storage space
-    tile_map tile_cache;
-
-    // maximum cache size
-    int max_cache_size;
-
-    // pointers to allow an external linear traversal of cache entries
-    tile_map_iterator current;
-
-    // Free a tile cache entry
-    void entry_free( long cache_index );
-
-public:
-    tile_map_iterator begin() { return tile_cache.begin(); }
-    tile_map_iterator end() { return tile_cache.end(); }
-    const_tile_map_iterator begin() const { return tile_cache.begin(); }
-    const_tile_map_iterator end() const { return tile_cache.end(); }
-    
-    // Constructor
-    FGNewCache();
-
-    // Destructor
-    ~FGNewCache();
-
-    // Initialize the tile cache subsystem 
-    void init( void );
-
-    // Check if the specified "bucket" exists in the cache
-    bool exists( const SGBucket& b ) const;
-
-#if 0
-    // Ensure at least one entry is free in the cache
-    bool make_space();
-#endif
-
-    // Return the index of the oldest tile in the cache, return -1 if
-    // nothing available to be removed.
-    long get_oldest_tile();
-
-    // Clear the inner ring flag for all tiles in the cache so that
-    // the external tile scheduler can flag the inner ring correctly.
-    void clear_inner_ring_flags();
-
-    // Clear a cache entry, note that the cache only holds pointers
-    // and this does not free the object which is pointed to.
-    void clear_entry( long cache_entry );
-
-    // Clear all completely loaded tiles (ignores partially loaded tiles)
-    void clear_cache();
-
-    // Return a pointer to the specified tile cache entry 
-    inline FGTileEntry *get_tile( const long tile_index ) const {
-	const_tile_map_iterator it = tile_cache.find( tile_index );
-	if ( it != tile_cache.end() ) {
-	    return it->second;
-	} else {
-	    return NULL;
-	}
-    }
-
-    // Return a pointer to the specified tile cache entry 
-    inline FGTileEntry *get_tile( const SGBucket& b ) const {
-	return get_tile( b.gen_index() );
-    }
-
-    // Return the cache size
-    inline size_t get_size() const { return tile_cache.size(); }
-
-    // External linear traversal of cache
-    inline void reset_traversal() { current = tile_cache.begin(); }
-    inline bool at_end() { return current == tile_cache.end(); }
-    inline FGTileEntry *get_current() const {
-	// cout << "index = " << current->first << endl;
-	return current->second;
-    }
-    inline void next() { ++current; }
-
-    inline int get_max_cache_size() const { return max_cache_size; }
-    inline void set_max_cache_size( int m ) { max_cache_size = m; }
-
-    /**
-     * Create a new tile and enqueue it for loading.
-     * @param b 
-     * @return success/failure
-     */
-    bool insert_tile( FGTileEntry* e );
-};
-
-
-#endif // _NEWCACHE_HXX 
diff --git a/src/Scenery/tileentry.cxx b/src/Scenery/tileentry.cxx
deleted file mode 100644
index 06f1192e3..000000000
--- a/src/Scenery/tileentry.cxx
+++ /dev/null
@@ -1,592 +0,0 @@
-// tileentry.cxx -- routines to handle a scenery tile
-//
-// Written by Curtis Olson, started May 1998.
-//
-// Copyright (C) 1998 - 2001  Curtis L. Olson  - http://www.flightgear.org/~curt
-//
-// This program is free software; you can redistribute it and/or
-// modify it under the terms of the GNU General Public License as
-// published by the Free Software Foundation; either version 2 of the
-// License, or (at your option) any later version.
-//
-// This program is distributed in the hope that it will be useful, but
-// WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-// General Public License for more details.
-//
-// You should have received a copy of the GNU General Public License
-// along with this program; if not, write to the Free Software
-// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
-//
-// $Id$
-
-
-#ifdef HAVE_CONFIG_H
-#  include <config.h>
-#endif
-
-#include <simgear/compiler.h>
-#include <plib/ul.h>
-#include <Main/main.hxx>
-
-
-#include STL_STRING
-#include <sstream>
-
-#include <osg/Array>
-#include <osg/Geometry>
-#include <osg/Geode>
-#include <osg/LOD>
-#include <osg/MatrixTransform>
-#include <osg/Math>
-#include <osg/NodeCallback>
-#include <osg/Switch>
-
-#include <osgDB/FileNameUtils>
-#include <osgDB/ReaderWriter>
-#include <osgDB/ReadFile>
-#include <osgDB/Registry>
-
-#include <simgear/bucket/newbucket.hxx>
-#include <simgear/debug/logstream.hxx>
-#include <simgear/math/polar3d.hxx>
-#include <simgear/math/sg_geodesy.hxx>
-#include <simgear/math/sg_random.h>
-#include <simgear/math/SGMath.hxx>
-#include <simgear/misc/sgstream.hxx>
-#include <simgear/scene/material/mat.hxx>
-#include <simgear/scene/material/matlib.hxx>
-#include <simgear/scene/model/ModelRegistry.hxx>
-#include <simgear/scene/tgdb/apt_signs.hxx>
-#include <simgear/scene/tgdb/obj.hxx>
-#include <simgear/scene/tgdb/SGReaderWriterBTGOptions.hxx>
-#include <simgear/scene/model/placementtrans.hxx>
-#include <simgear/scene/util/SGUpdateVisitor.hxx>
-
-#include <Aircraft/aircraft.hxx>
-#include <Include/general.hxx>
-#include <Main/fg_props.hxx>
-#include <Main/globals.hxx>
-#include <Main/viewer.hxx>
-#include <Scenery/scenery.hxx>
-#include <Time/light.hxx>
-
-#include "tileentry.hxx"
-#include "tilemgr.hxx"
-
-SG_USING_STD(string);
-using namespace simgear;
-
-// FIXME: investigate what huge update flood is clamped away here ...
-class FGTileUpdateCallback : public osg::NodeCallback {
-public:
-  virtual void operator()(osg::Node* node, osg::NodeVisitor* nv)
-  {
-    assert(dynamic_cast<SGUpdateVisitor*>(nv));
-    SGUpdateVisitor* updateVisitor = static_cast<SGUpdateVisitor*>(nv);
-
-    osg::Vec3 center = node->getBound().center();
-    double distance = dist(updateVisitor->getGlobalEyePos(),
-                           SGVec3d(center[0], center[1], center[2]));
-    if (updateVisitor->getVisibility() + node->getBound().radius() < distance)
-      return;
-
-    traverse(node, nv);
-  }
-};
-
-namespace
-{
-// Update the timestamp on a tile whenever it is in view.
-
-class TileCullCallback : public osg::NodeCallback
-{
-public:
-    TileCullCallback() : _timeStamp(0) {}
-    TileCullCallback(const TileCullCallback& tc, const osg::CopyOp& copyOp) :
-        NodeCallback(tc, copyOp), _timeStamp(tc._timeStamp)
-    {
-    }
-    
-    virtual void operator()(osg::Node* node, osg::NodeVisitor* nv);
-    double getTimeStamp() const { return _timeStamp; }
-    void setTimeStamp(double timeStamp) { _timeStamp = timeStamp; }
-protected:
-    double _timeStamp;
-};
-}
-
-void TileCullCallback::operator()(osg::Node* node, osg::NodeVisitor* nv)
-{
-    if (nv->getFrameStamp())
-        _timeStamp = nv->getFrameStamp()->getReferenceTime();
-    traverse(node, nv);
-}
-
-double FGTileEntry::get_timestamp() const
-{
-    if (_node.valid()) {
-        return (dynamic_cast<TileCullCallback*>(_node->getCullCallback()))
-            ->getTimeStamp();
-    } else
-        return DBL_MAX;
-}
-
-void FGTileEntry::set_timestamp(double time_ms)
-{
-    if (_node.valid()) {
-        TileCullCallback* cb
-            = dynamic_cast<TileCullCallback*>(_node->getCullCallback());
-        if (cb)
-            cb->setTimeStamp(time_ms);
-    }
-}
-
-// Constructor
-FGTileEntry::FGTileEntry ( const SGBucket& b )
-    : tile_bucket( b ),
-      _node( new osg::LOD ),
-      is_inner_ring(false),
-      free_tracker(0),
-      tileFileName(b.gen_index_str())
-{
-    _node->setUpdateCallback(new FGTileUpdateCallback);
-    _node->setCullCallback(new TileCullCallback);
-    tileFileName += ".stg";
-    _node->setName(tileFileName);
-    // Give a default LOD range so that traversals that traverse
-    // active children (like the groundcache lookup) will work before
-    // tile manager has had a chance to update this node.
-    _node->setRange(0, 0.0, 10000.0);
-}
-
-
-// Destructor
-FGTileEntry::~FGTileEntry ()
-{
-}
-
-static void WorldCoordinate(osg::Matrix& obj_pos, double lat,
-                            double lon, double elev, double hdg)
-{
-    SGGeod geod = SGGeod::fromDegM(lon, lat, elev);
-    obj_pos = geod.makeZUpFrame();
-    // hdg is not a compass heading, but a counter-clockwise rotation
-    // around the Z axis
-    obj_pos.preMult(osg::Matrix::rotate(hdg * SGD_DEGREES_TO_RADIANS,
-                                        0.0, 0.0, 1.0));
-}
-
-
-// Free "n" leaf elements of an ssg tree.  returns the number of
-// elements freed.  An empty branch node is considered a leaf.  This
-// is intended to spread the load of freeing a complex tile out over
-// several frames.
-static int fgPartialFreeSSGtree( osg::Group *b, int n ) {
-    int num_deletes = b->getNumChildren();
-
-    b->removeChildren(0, b->getNumChildren());
-
-    return num_deletes;
-}
-
-
-// Clean up the memory used by this tile and delete the arrays used by
-// ssg as well as the whole ssg branch
-bool FGTileEntry::free_tile() {
-    int delete_size = 100;
-    SG_LOG( SG_TERRAIN, SG_DEBUG,
-            "FREEING TILE = (" << tile_bucket << ")" );
-
-    SG_LOG( SG_TERRAIN, SG_DEBUG, "(start) free_tracker = " << free_tracker );
-    
-    if ( !(free_tracker & NODES) ) {
-        free_tracker |= NODES;
-    } else if ( !(free_tracker & VEC_PTRS) ) {
-        free_tracker |= VEC_PTRS;
-    } else if ( !(free_tracker & TERRA_NODE) ) {
-        // delete the terrain branch (this should already have been
-        // disconnected from the scene graph)
-        SG_LOG( SG_TERRAIN, SG_DEBUG, "FREEING terra_transform" );
-        if ( fgPartialFreeSSGtree( _node.get(), delete_size ) == 0 ) {
-            _node = 0;
-            free_tracker |= TERRA_NODE;
-        }
-    } else if ( !(free_tracker & LIGHTMAPS) ) {
-        free_tracker |= LIGHTMAPS;
-    } else {
-        return true;
-    }
-
-    SG_LOG( SG_TERRAIN, SG_DEBUG, "(end) free_tracker = " << free_tracker );
-
-    // if we fall down to here, we still have work todo, return false
-    return false;
-}
-
-
-// Update the ssg transform node for this tile so it can be
-// properly drawn relative to our (0,0,0) point
-void FGTileEntry::prep_ssg_node(float vis) {
-    if (!is_loaded())
-        return;
-    // visibility can change from frame to frame so we update the
-    // range selector cutoff's each time.
-    float bounding_radius = _node->getChild(0)->getBound().radius();
-    _node->setRange( 0, 0, vis + bounding_radius );
-}
-
-bool FGTileEntry::obj_load( const string& path,
-                            osg::Group *geometry, bool is_base )
-{
-    bool use_random_objects =
-        fgGetBool("/sim/rendering/random-objects", true);
-        
-    bool use_random_vegetation = 
-        fgGetBool("/sim/rendering/random-vegetation", true);
-
-    // try loading binary format
-    osg::ref_ptr<SGReaderWriterBTGOptions> options
-        = new SGReaderWriterBTGOptions();
-    options->setMatlib(globals->get_matlib());
-    options->setCalcLights(is_base);
-    options->setUseRandomObjects(use_random_objects);
-    options->setUseRandomVegetation(use_random_vegetation);
-    osg::Node* node = osgDB::readNodeFile(path, options.get());
-    if (node)
-      geometry->addChild(node);
-
-    return node;
-}
-
-
-typedef enum {
-    OBJECT,
-    OBJECT_SHARED,
-    OBJECT_STATIC,
-    OBJECT_SIGN,
-    OBJECT_RUNWAY_SIGN
-} object_type;
-
-
-// storage class for deferred object processing in FGTileEntry::load()
-struct Object {
-    Object(object_type t, const string& token, const SGPath& p, istream& in)
-        : type(t), path(p)
-    {
-        in >> name;
-        if (type != OBJECT)
-            in >> lon >> lat >> elev >> hdg;
-        in >> ::skipeol;
-
-        if (type == OBJECT)
-            SG_LOG(SG_TERRAIN, SG_INFO, "    " << token << "  " << name);
-        else
-            SG_LOG(SG_TERRAIN, SG_INFO, "    " << token << "  " << name << "  lon=" <<
-                    lon << "  lat=" << lat << "  elev=" << elev << "  hdg=" << hdg);
-    }
-    object_type type;
-    string name;
-    SGPath path;
-    double lon, lat, elev, hdg;
-};
-
-// Work in progress... load the tile based entirely by name cuz that's
-// what we'll want to do with the database pager.
-
-osg::Node*
-FGTileEntry::loadTileByName(const string& index_str,
-                            const string_list &path_list)
-{
-    long tileIndex;
-    {
-        istringstream idxStream(index_str);
-        idxStream >> tileIndex;
-    }
-    SGBucket tile_bucket(tileIndex);
-    const string basePath = tile_bucket.gen_base_path();
-    
-    bool found_tile_base = false;
-
-    SGPath object_base;
-    vector<const Object*> objects;
-
-    SG_LOG( SG_TERRAIN, SG_INFO, "Loading tile " << index_str );
-
-    // scan and parse all files and store information
-    for (unsigned int i = 0; i < path_list.size(); i++) {
-        // If we found a terrain tile in Terrain/, we have to process the
-        // Objects/ dir in the same group, too, before we can stop scanning.
-        // FGGlobals::set_fg_scenery() inserts an empty string to path_list
-        // as marker.
-        if (path_list[i].empty()) {
-            if (found_tile_base)
-                break;
-            else
-                continue;
-        }
-
-        bool has_base = false;
-
-        SGPath tile_path = path_list[i];
-        tile_path.append(basePath);
-
-        SGPath basename = tile_path;
-        basename.append( index_str );
-
-        SG_LOG( SG_TERRAIN, SG_INFO, "  Trying " << basename.str() );
-
-
-        // Check for master .stg (scene terra gear) file
-        SGPath stg_name = basename;
-        stg_name.concat( ".stg" );
-
-        sg_gzifstream in( stg_name.str() );
-        if ( !in.is_open() )
-            continue;
-
-        while ( ! in.eof() ) {
-            string token;
-            in >> token;
-
-            if ( token.empty() || token[0] == '#' ) {
-               in >> ::skipeol;
-               continue;
-            }
-                            // Load only once (first found)
-            if ( token == "OBJECT_BASE" ) {
-                string name;
-                in >> name >> ::skipws;
-                SG_LOG( SG_TERRAIN, SG_INFO, "    " << token << " " << name );
-
-                if (!found_tile_base) {
-                    found_tile_base = true;
-                    has_base = true;
-
-                    object_base = tile_path;
-                    object_base.append(name);
-
-                } else
-                    SG_LOG(SG_TERRAIN, SG_INFO, "    (skipped)");
-
-                            // Load only if base is not in another file
-            } else if ( token == "OBJECT" ) {
-                if (!found_tile_base || has_base)
-                    objects.push_back(new Object(OBJECT, token, tile_path, in));
-                else {
-                    string name;
-                    in >> name >> ::skipeol;
-                    SG_LOG(SG_TERRAIN, SG_INFO, "    " << token << "  "
-                            << name << "  (skipped)");
-                }
-
-                            // Always OK to load
-            } else if ( token == "OBJECT_STATIC" ) {
-                objects.push_back(new Object(OBJECT_STATIC, token, tile_path, in));
-
-            } else if ( token == "OBJECT_SHARED" ) {
-                objects.push_back(new Object(OBJECT_SHARED, token, tile_path, in));
-
-            } else if ( token == "OBJECT_SIGN" ) {
-                objects.push_back(new Object(OBJECT_SIGN, token, tile_path, in));
-
-            } else if ( token == "OBJECT_RUNWAY_SIGN" ) {
-                objects.push_back(new Object(OBJECT_RUNWAY_SIGN, token, tile_path, in));
-
-            } else {
-                SG_LOG( SG_TERRAIN, SG_DEBUG,
-                        "Unknown token '" << token << "' in " << stg_name.str() );
-                in >> ::skipws;
-            }
-        }
-    }
-
-
-    // obj_load() will generate ground lighting for us ...
-    osg::Group* new_tile = new osg::Group;
-
-    if (found_tile_base) {
-        // load tile if found ...
-        obj_load( object_base.str(), new_tile, true );
-
-    } else {
-        // ... or generate an ocean tile on the fly
-        SG_LOG(SG_TERRAIN, SG_INFO, "  Generating ocean tile");
-        if ( !SGGenTile( path_list[0], tile_bucket,
-                        globals->get_matlib(), new_tile ) ) {
-            SG_LOG( SG_TERRAIN, SG_ALERT,
-                    "Warning: failed to generate ocean tile!" );
-        }
-    }
-
-
-    // now that we have a valid center, process all the objects
-    for (unsigned int j = 0; j < objects.size(); j++) {
-        const Object *obj = objects[j];
-
-        if (obj->type == OBJECT) {
-            SGPath custom_path = obj->path;
-            custom_path.append( obj->name );
-            obj_load( custom_path.str(), new_tile, false );
-
-        } else if (obj->type == OBJECT_SHARED || obj->type == OBJECT_STATIC) {
-            // object loading is deferred to main render thread,
-            // but lets figure out the paths right now.
-            SGPath custom_path;
-            if ( obj->type == OBJECT_STATIC ) {
-                custom_path = obj->path;
-            } else {
-                // custom_path = globals->get_fg_root();
-            }
-            custom_path.append( obj->name );
-
-            osg::Matrix obj_pos;
-            WorldCoordinate( obj_pos, obj->lat, obj->lon, obj->elev, obj->hdg );
-
-            osg::MatrixTransform *obj_trans = new osg::MatrixTransform;
-            obj_trans->setMatrix( obj_pos );
-
-            // wire as much of the scene graph together as we can
-            new_tile->addChild( obj_trans );
-
-            osg::Node* model
-                = FGTileMgr::loadTileModel(custom_path.str(),
-                                           obj->type == OBJECT_SHARED);
-            if (model)
-                obj_trans->addChild(model);
-        } else if (obj->type == OBJECT_SIGN || obj->type == OBJECT_RUNWAY_SIGN) {
-            // load the object itself
-            SGPath custom_path = obj->path;
-            custom_path.append( obj->name );
-
-            osg::Matrix obj_pos;
-            WorldCoordinate( obj_pos, obj->lat, obj->lon, obj->elev, obj->hdg );
-
-            osg::MatrixTransform *obj_trans = new osg::MatrixTransform;
-            obj_trans->setMatrix( obj_pos );
-
-            osg::Node *custom_obj = 0;
-            if (obj->type == OBJECT_SIGN)
-                custom_obj = SGMakeSign(globals->get_matlib(), custom_path.str(), obj->name);
-            else
-                custom_obj = SGMakeRunwaySign(globals->get_matlib(), custom_path.str(), obj->name);
-
-            // wire the pieces together
-            if ( custom_obj != NULL ) {
-                obj_trans -> addChild( custom_obj );
-            }
-            new_tile->addChild( obj_trans );
-
-        }
-        delete obj;
-    }
-    return new_tile;
-}
-
-void
-FGTileEntry::add_ssg_nodes( osg::Group *terrain_branch )
-{
-    // bump up the ref count so we can remove this later without
-    // having ssg try to free the memory.
-    terrain_branch->addChild( _node.get() );
-
-    SG_LOG( SG_TERRAIN, SG_DEBUG,
-            "connected a tile into scene graph.  _node = "
-            << _node.get() );
-    SG_LOG( SG_TERRAIN, SG_DEBUG, "num parents now = "
-            << _node->getNumParents() );
-}
-
-
-void
-FGTileEntry::disconnect_ssg_nodes()
-{
-    SG_LOG( SG_TERRAIN, SG_DEBUG, "disconnecting ssg nodes" );
-
-    if (! is_loaded()) {
-        SG_LOG( SG_TERRAIN, SG_DEBUG, "removing a not-fully loaded tile!" );
-    } else {
-        SG_LOG( SG_TERRAIN, SG_DEBUG, "removing a fully loaded tile!  _node = " << _node.get() );
-    }
-        
-    // find the terrain branch parent
-    int pcount = _node->getNumParents();
-    if ( pcount > 0 ) {
-        // find the first parent (should only be one)
-        osg::Group *parent = _node->getParent( 0 ) ;
-        if( parent ) {
-            // disconnect the tile (we previously ref()'d it so it
-            // won't get freed now)
-            parent->removeChild( _node.get() );
-        } else {
-            // This should be impossible.
-            SG_LOG( SG_TERRAIN, SG_ALERT,
-                    "parent pointer is NULL!  Dying" );
-            exit(-1);
-        }
-    }
-}
-
-namespace
-{
-
-class ReaderWriterSTG : public osgDB::ReaderWriter {
-public:
-    virtual const char* className() const;
- 
-    virtual bool acceptsExtension(const string& extension) const;
-
-    virtual ReadResult readNode(const string& fileName,
-                                const osgDB::ReaderWriter::Options* options)
-        const;
-};
-
-const char* ReaderWriterSTG::className() const
-{
-    return "STG Database reader";
-}
-
-bool ReaderWriterSTG::acceptsExtension(const string& extension) const
-{
-    return (osgDB::equalCaseInsensitive(extension, "gz")
-            || osgDB::equalCaseInsensitive(extension, "stg"));   
-}
-
-//#define SLOW_PAGER 1
-#ifdef SLOW_PAGER
-#include <unistd.h>
-#endif
-
-osgDB::ReaderWriter::ReadResult
-ReaderWriterSTG::readNode(const string& fileName,
-                          const osgDB::ReaderWriter::Options* options) const
-{
-    string ext = osgDB::getLowerCaseFileExtension(fileName);
-    if(!acceptsExtension(ext))
-        return ReadResult::FILE_NOT_HANDLED;
-    string stgFileName;
-    if (osgDB::equalCaseInsensitive(ext, "gz")) {
-        stgFileName = osgDB::getNameLessExtension(fileName);
-        if (!acceptsExtension(
-                osgDB::getLowerCaseFileExtension(stgFileName))) {
-            return ReadResult::FILE_NOT_HANDLED;
-        }
-    } else {
-        stgFileName = fileName;
-    }
-    osg::Node* result
-        = FGTileEntry::loadTileByName(osgDB::getNameLessExtension(stgFileName),
-                                      globals->get_fg_scenery());
-    // For debugging race conditions
-#ifdef SLOW_PAGER
-    sleep(5);
-#endif
-    if (result)
-        return result;           // Constructor converts to ReadResult
-    else
-        return ReadResult::FILE_NOT_HANDLED;
-}
-
-osgDB::RegisterReaderWriterProxy<ReaderWriterSTG> g_readerWriterSTGProxy;
-ModelRegistryCallbackProxy<LoadOnlyCallback> g_stgCallbackProxy("stg");
-} // namespace
diff --git a/src/Scenery/tileentry.hxx b/src/Scenery/tileentry.hxx
deleted file mode 100644
index 70bbbc279..000000000
--- a/src/Scenery/tileentry.hxx
+++ /dev/null
@@ -1,215 +0,0 @@
-// tileentry.hxx -- routines to handle an individual scenery tile
-//
-// Written by Curtis Olson, started May 1998.
-//
-// Copyright (C) 1998 - 2001  Curtis L. Olson  - http://www.flightgear.org/~curt
-//
-// This program is free software; you can redistribute it and/or
-// modify it under the terms of the GNU General Public License as
-// published by the Free Software Foundation; either version 2 of the
-// License, or (at your option) any later version.
-//
-// This program is distributed in the hope that it will be useful, but
-// WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-// General Public License for more details.
-//
-// You should have received a copy of the GNU General Public License
-// along with this program; if not, write to the Free Software
-// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
-//
-// $Id$
-
-
-#ifndef _TILEENTRY_HXX
-#define _TILEENTRY_HXX
-
-
-#ifndef __cplusplus
-# error This library requires C++
-#endif
-
-#ifdef HAVE_CONFIG_H
-#  include <config.h>
-#endif
-
-#include <simgear/compiler.h>
-
-#include <vector>
-#include STL_STRING
-
-#include <simgear/bucket/newbucket.hxx>
-#include <simgear/math/point3d.hxx>
-#include <simgear/misc/sg_path.hxx>
-#include <simgear/scene/model/placementtrans.hxx>
-
-#include <osg/ref_ptr>
-#include <osg/Array>
-#include <osg/Group>
-#include <osg/LOD>
-#include <osg/MatrixTransform>
-#include <osg/Switch>
-
-#if defined( sgi )
-#include <strings.h>
-#endif
-
-SG_USING_STD(string);
-SG_USING_STD(vector);
-
-
-typedef vector < Point3D > point_list;
-typedef point_list::iterator point_list_iterator;
-typedef point_list::const_iterator const_point_list_iterator;
-
-
-class FGTileEntry;
-
-#if 0
-/**
- * A class to hold deferred model loading info
- */
-class FGDeferredModel {
-
-private:
-
-    string model_path;
-    string texture_path;
-    FGTileEntry *tile;
-    osg::ref_ptr<osg::MatrixTransform> obj_trans;
-    SGBucket bucket;
-    bool cache_obj;
-
-
-public:
-
-    inline FGDeferredModel() { }
-    inline FGDeferredModel( const string& mp, const string& tp, SGBucket b,
-                            FGTileEntry *t, osg::MatrixTransform *ot, bool co )
-    {
-	model_path = mp;
-	texture_path = tp;
-        bucket = b;
-	tile = t;
-	obj_trans = ot;
-	cache_obj = co;
-    }
-    inline ~FGDeferredModel() { }
-    inline const string& get_model_path() const { return model_path; }
-    inline const string& get_texture_path() const { return texture_path; }
-    inline const SGBucket& get_bucket() const { return bucket; }
-    inline const bool get_cache_state() const { return cache_obj; }
-    inline FGTileEntry *get_tile() const { return tile; }
-    inline osg::MatrixTransform *get_obj_trans() const { return obj_trans.get(); }
-};
-#endif
-
-/**
- * A class to encapsulate everything we need to know about a scenery tile.
- */
-class FGTileEntry {
-
-public:
-    // this tile's official location in the world
-    SGBucket tile_bucket;
-    std::string tileFileName;
-
-private:
-
-    // pointer to ssg range selector for this tile
-    osg::ref_ptr<osg::LOD> _node;
-
-    static bool obj_load( const std::string& path,
-                          osg::Group* geometry,
-                          bool is_base );
-
-    /**
-     * this value is used by the tile scheduler/loader to mark which
-     * tiles are in the primary ring (i.e. the current tile or the
-     * surrounding eight.)  Other routines then can use this as an
-     * optimization and not do some operation to tiles outside of this
-     * inner ring.  (For instance vasi color updating)
-     */
-    bool is_inner_ring;
-
-    /**
-     * this variable tracks the status of the incremental memory
-     * freeing.
-     */
-    enum {
-        NODES = 0x01,
-        VEC_PTRS = 0x02,
-        TERRA_NODE = 0x04,
-        GROUND_LIGHTS = 0x08,
-        VASI_LIGHTS = 0x10,
-        RWY_LIGHTS = 0x20,
-        TAXI_LIGHTS = 0x40,
-        LIGHTMAPS = 0x80
-    };
-    int free_tracker;
-
-public:
-
-    // Constructor
-    FGTileEntry( const SGBucket& b );
-
-    // Destructor
-    ~FGTileEntry();
-
-    // Clean up the memory used by this tile and delete the arrays
-    // used by ssg as well as the whole ssg branch.  This does a
-    // partial clean up and exits so we can spread the load across
-    // multiple frames.  Returns false if work remaining to be done,
-    // true if dynamically allocated memory used by this tile is
-    // completely freed.
-    bool free_tile();
-
-    // Update the ssg transform node for this tile so it can be
-    // properly drawn relative to our (0,0,0) point
-    void prep_ssg_node(float vis);
-
-    /**
-     * Transition to OSG database pager
-     */
-    static osg::Node* loadTileByName(const std::string& index_str,
-                                     const string_list &path_list);
-    /**
-     * Return true if the tile entry is loaded, otherwise return false
-     * indicating that the loading thread is still working on this.
-     */
-    inline bool is_loaded() const
-    {
-        return _node->getNumChildren() > 0;
-    }
-
-    /**
-     * Return the "bucket" for this tile
-     */
-    inline const SGBucket& get_tile_bucket() const { return tile_bucket; }
-
-    /**
-     * Add terrain mesh and ground lighting to scene graph.
-     */
-    void add_ssg_nodes( osg::Group *terrain_branch);
-
-    /**
-     * disconnect terrain mesh and ground lighting nodes from scene
-     * graph for this tile.
-     */
-    void disconnect_ssg_nodes();
-
-	
-    /**
-     * return the scenegraph node for the terrain
-     */
-    osg::LOD *getNode() const { return _node.get(); }
-
-    double get_timestamp() const;
-    void set_timestamp( double time_ms );
-
-    inline bool get_inner_ring() const { return is_inner_ring; }
-    inline void set_inner_ring( bool val ) { is_inner_ring = val; }
-};
-
-
-#endif // _TILEENTRY_HXX 
diff --git a/src/Scenery/tilemgr.cxx b/src/Scenery/tilemgr.cxx
index adf548d54..033bf2d5b 100644
--- a/src/Scenery/tilemgr.cxx
+++ b/src/Scenery/tilemgr.cxx
@@ -36,6 +36,7 @@
 #include <simgear/math/vector.hxx>
 #include <simgear/structure/exception.hxx>
 #include <simgear/scene/model/modellib.hxx>
+#include <simgear/scene/tgdb/SGReaderWriterBTGOptions.hxx>
 
 #include <Main/globals.hxx>
 #include <Main/fg_props.hxx>
@@ -43,7 +44,6 @@
 #include <Main/viewer.hxx>
 #include <Scripting/NasalSys.hxx>
 
-#include "newcache.hxx"
 #include "scenery.hxx"
 #include "SceneryPager.hxx"
 #include "tilemgr.hxx"
@@ -51,20 +51,20 @@
 using std::for_each;
 using flightgear::SceneryPager;
 using simgear::SGModelLib;
+using simgear::TileEntry;
+using simgear::TileCache;
 
-#define TEST_LAST_HIT_CACHE
-
-// Constructor
 FGTileMgr::FGTileMgr():
     state( Start ),
-    current_tile( NULL ),
     vis( 16000 )
 {
 }
 
 
-// Destructor
 FGTileMgr::~FGTileMgr() {
+    // remove all nodes we might have left behind
+    osg::Group* group = globals->get_scenery()->get_terrain_branch();
+    group->removeChildren(0, group->getNumChildren());
 }
 
 
@@ -72,6 +72,17 @@ FGTileMgr::~FGTileMgr() {
 int FGTileMgr::init() {
     SG_LOG( SG_TERRAIN, SG_INFO, "Initializing Tile Manager subsystem." );
 
+    _options = new SGReaderWriterBTGOptions;
+    _options->setMatlib(globals->get_matlib());
+    _options->setUseRandomObjects(fgGetBool("/sim/rendering/random-objects", true));
+    _options->setUseRandomVegetation(fgGetBool("/sim/rendering/random-vegetation", true));
+    osgDB::FilePathList &fp = _options->getDatabasePathList();
+    const string_list &sc = globals->get_fg_scenery();
+    fp.clear();
+    std::copy(sc.begin(), sc.end(), back_inserter(fp));
+
+    TileEntry::setModelLoadHelper(this);
+
     tile_cache.init();
 
     state = Inited;
@@ -84,22 +95,21 @@ int FGTileMgr::init() {
     return 1;
 }
 
-
 // schedule a tile for loading
 void FGTileMgr::sched_tile( const SGBucket& b, const bool is_inner_ring ) {
     // see if tile already exists in the cache
-    FGTileEntry *t = tile_cache.get_tile( b );
+    TileEntry *t = tile_cache.get_tile( b );
 
-    if ( t == NULL ) {
+    if ( !t ) {
         // make space in the cache
         SceneryPager* pager = FGScenery::getPagerSingleton();
         while ( (int)tile_cache.get_size() > tile_cache.get_max_cache_size() ) {
             long index = tile_cache.get_oldest_tile();
             if ( index >= 0 ) {
-                FGTileEntry *old = tile_cache.get_tile( index );
+                TileEntry *old = tile_cache.get_tile( index );
                 tile_cache.clear_entry( index );
                 osg::ref_ptr<osg::Object> subgraph = old->getNode();
-                old->disconnect_ssg_nodes();
+                old->removeFromSceneGraph();
                 delete old;
                 // zeros out subgraph ref_ptr, so subgraph is owned by
                 // the pager and will be deleted in the pager thread.
@@ -111,7 +121,7 @@ void FGTileMgr::sched_tile( const SGBucket& b, const bool is_inner_ring ) {
         }
 
         // create a new entry
-        FGTileEntry *e = new FGTileEntry( b );
+        TileEntry *e = new TileEntry( b );
 
         // insert the tile into the cache
         if ( tile_cache.insert_tile( e ) ) {
@@ -122,7 +132,7 @@ void FGTileMgr::sched_tile( const SGBucket& b, const bool is_inner_ring ) {
             delete e;
         }
         // Attach to scene graph
-        e->add_ssg_nodes(globals->get_scenery()->get_terrain_branch());
+        e->addToSceneGraph(globals->get_scenery()->get_terrain_branch());
     } else {
         t->set_inner_ring( is_inner_ring );
     }
@@ -159,7 +169,8 @@ void FGTileMgr::schedule_needed( double vis, const SGBucket& curr_bucket) {
     if ( xrange < 1 ) { xrange = 1; }
     if ( yrange < 1 ) { yrange = 1; }
 
-    // note * 2 at end doubles cache size (for fdm and viewer)
+    // make the cache twice as large to avoid losing terrain when switching
+    // between aircraft and tower views
     tile_cache.set_max_cache_size( (2*xrange + 2) * (2*yrange + 2) * 2 );
     // cout << "xrange = " << xrange << "  yrange = " << yrange << endl;
     // cout << "max cache size = " << tile_cache.get_max_cache_size()
@@ -221,23 +232,6 @@ void FGTileMgr::initialize_queue()
 
     double visibility_meters = fgGetDouble("/environment/visibility-m");
     schedule_needed(visibility_meters, current_bucket);
-
-    // do we really want to lose this? CLO
-#if 0
-    // Now force a load of the center tile and inner ring so we
-    // have something to see in our first frame.
-    int i;
-    for ( i = 0; i < 9; ++i ) {
-        if ( load_queue.size() ) {
-            SG_LOG( SG_TERRAIN, SG_DEBUG, 
-                    "Load queue not empty, loading a tile" );
-
-            SGBucket pending = load_queue.front();
-            load_queue.pop_front();
-            load_tile( pending );
-        }
-    }
-#endif
 }
 
 osg::Node*
@@ -246,17 +240,14 @@ FGTileMgr::loadTileModel(const string& modelPath, bool cacheModel)
     osg::Node* result = 0;
     try {
         if(cacheModel)
-        {
             result =
                 SGModelLib::loadModel(modelPath, globals->get_props(),
                                       new FGNasalModelData);
-        }
+
         else
-        {
             result=
                 SGModelLib::loadPagedModel(modelPath, globals->get_props(),
                                            new FGNasalModelData);
-        }
     } catch (const sg_io_exception& exc) {
         string m(exc.getMessage());
         m += " ";
@@ -269,28 +260,32 @@ FGTileMgr::loadTileModel(const string& modelPath, bool cacheModel)
 }
 
 // Helper class for STL fun
-class TileLoad : public std::unary_function<FGNewCache::tile_map::value_type,
+class TileLoad : public std::unary_function<TileCache::tile_map::value_type,
                                             void>
 {
 public:
     TileLoad(SceneryPager *pager, osg::FrameStamp* framestamp,
-             osg::Group* terrainBranch) :
-        _pager(pager), _framestamp(framestamp) {}
+             osg::Group* terrainBranch, osgDB::ReaderWriter::Options* options) :
+        _pager(pager), _framestamp(framestamp), _options(options) {}
+
     TileLoad(const TileLoad& rhs) :
-        _pager(rhs._pager), _framestamp(rhs._framestamp) {}
-    void operator()(FGNewCache::tile_map::value_type& tilePair)
+        _pager(rhs._pager), _framestamp(rhs._framestamp),
+        _options(rhs._options) {}
+
+    void operator()(TileCache::tile_map::value_type& tilePair)
     {
-        FGTileEntry* entry = tilePair.second;
+        TileEntry* entry = tilePair.second;
         if (entry->getNode()->getNumChildren() == 0) {
             _pager->queueRequest(entry->tileFileName,
                                  entry->getNode(),
                                  entry->get_inner_ring() ? 10.0f : 1.0f,
-                                 _framestamp);
+                                 _framestamp, _options);
         }
     }
 private:
     SceneryPager* _pager;
     osg::FrameStamp* _framestamp;
+    osgDB::ReaderWriter::Options* _options;
 };
 
 /**
@@ -303,7 +298,7 @@ void FGTileMgr::update_queues()
     for_each(tile_cache.begin(), tile_cache.end(),
              TileLoad(pager,
                       globals->get_renderer()->getViewer()->getFrameStamp(),
-                      globals->get_scenery()->get_terrain_branch()));
+                      globals->get_scenery()->get_terrain_branch(), _options.get()));
 }
 
 
@@ -374,7 +369,7 @@ void FGTileMgr::prep_ssg_nodes(float vis) {
     // traverse the potentially viewable tile list and update range
     // selector and transform
 
-    FGTileEntry *e;
+    TileEntry *e;
     tile_cache.reset_traversal();
 
     while ( ! tile_cache.at_end() ) {
@@ -395,7 +390,7 @@ bool FGTileMgr::scenery_available(double lat, double lon, double range_m)
     return false;
   
   SGBucket bucket(lon, lat);
-  FGTileEntry *te = tile_cache.get_tile(bucket);
+  TileEntry *te = tile_cache.get_tile(bucket);
   if (!te || !te->is_loaded())
     return false;
 
@@ -412,7 +407,7 @@ bool FGTileMgr::scenery_available(double lat, double lon, double range_m)
       // We have already checked for the center tile.
       if ( x != 0 || y != 0 ) {
         SGBucket b = sgBucketOffset( lon, lat, x, y );
-        FGTileEntry *te = tile_cache.get_tile(b);
+        TileEntry *te = tile_cache.get_tile(b);
         if (!te || !te->is_loaded())
           return false;
       }
@@ -426,9 +421,9 @@ bool FGTileMgr::scenery_available(double lat, double lon, double range_m)
 namespace
 {
 struct IsTileLoaded :
-        public std::unary_function<FGNewCache::tile_map::value_type, bool>
+        public std::unary_function<TileCache::tile_map::value_type, bool>
 {
-    bool operator()(const FGNewCache::tile_map::value_type& tilePair) const
+    bool operator()(const TileCache::tile_map::value_type& tilePair) const
     {
         return tilePair.second->is_loaded();
     }
diff --git a/src/Scenery/tilemgr.hxx b/src/Scenery/tilemgr.hxx
index 63a049273..60752f910 100644
--- a/src/Scenery/tilemgr.hxx
+++ b/src/Scenery/tilemgr.hxx
@@ -24,30 +24,18 @@
 #ifndef _TILEMGR_HXX
 #define _TILEMGR_HXX
 
-
-#ifndef __cplusplus                                                          
-# error This library requires C++
-#endif                                   
-
 #include <simgear/compiler.h>
 #include <simgear/math/point3d.hxx>
 #include <simgear/scene/model/location.hxx>
 
 #include <simgear/bucket/newbucket.hxx>
-#include "newcache.hxx"
-
-#if defined(USE_MEM) || defined(WIN32)
-#  define FG_MEM_COPY(to,from,n)        memcpy(to, from, n)
-#else
-#  define FG_MEM_COPY(to,from,n)        bcopy(from, to, n)
-#endif
-
-// forward declaration
-class FGTileEntry;
+#include <simgear/scene/tgdb/TileEntry.hxx>
+#include <simgear/scene/tgdb/TileCache.hxx>
 
+class SGReaderWriterBTGOptions;
 class osg::Node;
 
-class FGTileMgr {
+class FGTileMgr : public simgear::ModelLoadHelper {
 
 private:
 
@@ -72,13 +60,12 @@ private:
     SGBucket previous_bucket;
     SGBucket current_bucket;
     SGBucket pending;
-	
-    FGTileEntry *current_tile;
-	
+    osg::ref_ptr<SGReaderWriterBTGOptions> _options;
+
     // x and y distance of tiles to load/draw
     float vis;
     int xrange, yrange;
-	
+
     // current longitude latitude
     double longitude;
     double latitude;
@@ -87,17 +74,14 @@ private:
     /**
      * tile cache
      */
-    FGNewCache tile_cache;
+    simgear::TileCache tile_cache;
 
 public:
-
-    // Constructor
     FGTileMgr();
 
-    // Destructor
     ~FGTileMgr();
 
-    // Initialize the Tile Manager subsystem
+    // Initialize the Tile Manager
     int init();
 
     // Update the various queues maintained by the tilemagr (private
@@ -124,7 +108,7 @@ public:
     bool scenery_available(double lat, double lon, double range_m);
 
     // Load a model for a tile
-    static osg::Node* loadTileModel(const string& modelPath, bool cacheModel);
+    osg::Node* loadTileModel(const string& modelPath, bool cacheModel);
 
     // Returns true if all the tiles in the tile cache have been loaded
     bool isSceneryLoaded();