sg: move most scenery-related code to simgear

From Till Busch

projects/VC7.1/SimGear.vcproj

@@ -893,6 +893,21 @@
 			<File
 				RelativePath="..\..\simgear\scene\tgdb\userdata.hxx">
 			</File>
+			<File
+				RelativePath="..\..\simgear\scene\tgdb\TileCache.cxx">
+			</File>
+			<File
+				RelativePath="..\..\simgear\scene\tgdb\TileCache.hxx">
+			</File>
+			<File
+				RelativePath="..\..\simgear\scene\tgdb\TileEntry.cxx">
+			</File>
+			<File
+				RelativePath="..\..\simgear\scene\tgdb\TileEntry.hxx">
+			</File>
+			<File
+				RelativePath="..\..\simgear\scene\tgdb\ReaderWriterSTG.cxx">
+			</File>
 		</Filter>
 		<Filter
 			Name="Lib_sgthread"

simgear/scene/model/ModelRegistry.cxx

@@ -252,7 +252,7 @@ public:
     texture = dynamic_cast<Texture*>(refAttr.first.get());
     if (!texture)
       return;
-    
+
     texture->setDataVariance(Object::STATIC);
   }
 
@@ -406,7 +406,7 @@ osg::Node* OptimizeModelPolicy::optimize(osg::Node* node,
     // STATIC so that textures will be globally shared.
     SGTexDataVarianceVisitor dataVarianceVisitor;
     node->accept(dataVarianceVisitor);
-      
+
     SGTexCompressionVisitor texComp;
     node->accept(texComp);
     return node;
@@ -585,4 +585,4 @@ typedef ModelRegistryCallback<ACProcessPolicy, DefaultCachePolicy,
 namespace
 {
 ModelRegistryCallbackProxy<ACCallback> g_acRegister("ac");
-}   
+}

simgear/scene/model/SGReaderWriterXML.cxx

@@ -181,6 +181,7 @@ sgLoad3DModel_internal(const string &path,
             throw sg_io_exception("Failed to load 3D model",
                                   sg_location(modelpath.str()));
     }
+    model->setName(modelpath.str());
 
     bool needTransform=false;
     // Set up the alignment node if needed

simgear/scene/tgdb/Makefile.am

@@ -9,6 +9,7 @@ include_HEADERS = \
 	obj.hxx \
 	pt_lights.hxx \
 	userdata.hxx \
+	ReaderWriterSTG.hxx \
 	SGOceanTile.hxx \
 	SGVasiDrawable.hxx \
 	SGDirectionalLightBin.hxx \
@@ -19,18 +20,23 @@ include_HEADERS = \
 	SGTriangleBin.hxx \
 	SGVertexArrayBin.hxx \
 	GroundLightManager.hxx \
-	ShaderGeometry.hxx
+	ShaderGeometry.hxx \
+	TileCache.hxx \
+	TileEntry.hxx
 
 libsgtgdb_a_SOURCES = \
 	apt_signs.cxx \
 	obj.cxx \
 	pt_lights.cxx \
 	userdata.cxx \
+	ReaderWriterSTG.cxx \
 	SGOceanTile.cxx \
 	SGReaderWriterBTG.cxx \
 	SGVasiDrawable.cxx \
 	GroundLightManager.cxx \
 	ShaderGeometry.cxx \
+	TileCache.cxx \
+	TileEntry.cxx \
 	TreeBin.cxx
 
 INCLUDES = -I$(top_srcdir)

simgear/scene/tgdb/ReaderWriterSTG.cxx

@@ -0,0 +1,77 @@
+// 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.
+//
+
+#include <simgear/scene/model/ModelRegistry.hxx>
+
+#include <osgDB/Registry>
+#include <osgDB/FileNameUtils>
+
+#include "TileEntry.hxx"
+#include "ReaderWriterSTG.hxx"
+
+using namespace simgear;
+
+const char* ReaderWriterSTG::className() const
+{
+    return "STG Database reader";
+}
+
+bool ReaderWriterSTG::acceptsExtension(const std::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 std::string& fileName,
+                          const osgDB::ReaderWriter::Options* options) const
+{
+    std::string ext = osgDB::getLowerCaseFileExtension(fileName);
+    if(!acceptsExtension(ext))
+        return ReadResult::FILE_NOT_HANDLED;
+    std::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
+        = TileEntry::loadTileByName(osgDB::getNameLessExtension(stgFileName),
+                                      options);
+    // For debugging race conditions
+#ifdef SLOW_PAGER
+    sleep(5);
+#endif
+    if (result)
+        return result;
+    else
+        return ReadResult::FILE_NOT_HANDLED;
+}
+

simgear/scene/tgdb/ReaderWriterSTG.hxx

@@ -0,0 +1,41 @@
+// 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.
+
+
+#ifndef _READERWRITERSTG_HXX
+#define _READERWRITERSTG_HXX
+
+#include <osgDB/ReaderWriter>
+
+namespace simgear {
+
+class ReaderWriterSTG : public osgDB::ReaderWriter {
+public:
+    virtual const char* className() const;
+
+    virtual bool acceptsExtension(const std::string& extension) const;
+
+    virtual ReadResult readNode(const std::string& fileName,
+                                const osgDB::ReaderWriter::Options* options)
+        const;
+};
+
+}
+#endif // _READERWRITERSTG_HXX

simgear/scene/tgdb/SGReaderWriterBTGOptions.hxx

@@ -15,7 +15,7 @@
 // Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 //
 #ifndef SGREADERWRITERBTGOPTIONS_HXX
-#define SGREADERWRITERBTGOPTIONS_HXX 1
+#define SGREADERWRITERBTGOPTIONS_HXX
 
 #include <osgDB/ReaderWriter>
 #include <simgear/scene/tgdb/obj.hxx>
@@ -28,7 +28,7 @@ public:
         _useRandomObjects(false),
         _useRandomVegetation(false)
     {}
-    
+
     SGReaderWriterBTGOptions(const SGReaderWriterBTGOptions& options,
             const osg::CopyOp& copyop=osg::CopyOp::SHALLOW_COPY):
         osgDB::ReaderWriter::Options(options, copyop),

simgear/scene/tgdb/TileCache.cxx

@@ -0,0 +1,171 @@
+// 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.
+//
+// $Id$
+
+#include <simgear/bucket/newbucket.hxx>
+#include <simgear/debug/logstream.hxx>
+#include <simgear/misc/sg_path.hxx>
+
+#include "TileEntry.hxx"
+#include "TileCache.hxx"
+
+SG_USING_NAMESPACE(std);
+
+using simgear::TileEntry;
+using simgear::TileCache;
+
+TileCache::TileCache( void ) :
+    max_cache_size(100)
+{
+    tile_cache.clear();
+}
+
+
+TileCache::~TileCache( void ) {
+    clear_cache();
+}
+
+
+// Free a tile cache entry
+void TileCache::entry_free( long cache_index ) {
+    SG_LOG( SG_TERRAIN, SG_DEBUG, "FREEING CACHE ENTRY = " << cache_index );
+    TileEntry *tile = tile_cache[cache_index];
+    tile->removeFromSceneGraph();
+
+    tile->free_tile();
+    delete tile;
+
+    tile_cache.erase( cache_index );
+}
+
+
+// Initialize the tile cache subsystem
+void TileCache::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 TileCache::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 TileCache::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;
+        TileEntry *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 TileCache::clear_inner_ring_flags() {
+    tile_map_iterator current = tile_cache.begin();
+    tile_map_iterator end = tile_cache.end();
+
+    for ( ; current != end; ++current ) {
+        TileEntry *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 TileCache::clear_entry( long cache_index ) {
+    tile_cache.erase( cache_index );
+}
+
+
+// Clear all completely loaded tiles (ignores partially loaded tiles)
+void TileCache::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 );
+        TileEntry *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]);
+    }
+}
+
+/**
+ * Create a new tile and schedule it for loading.
+ */
+bool TileCache::insert_tile( TileEntry *e ) {
+    // register tile in the cache
+    long tile_index = e->get_tile_bucket().gen_index();
+    tile_cache[tile_index] = e;
+
+    return true;
+}
+

simgear/scene/tgdb/TileCache.hxx

@@ -0,0 +1,129 @@
+// 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 _TILECACHE_HXX
+#define _TILECACHE_HXX
+
+#include <map>
+
+#include <simgear/bucket/newbucket.hxx>
+#include <simgear/math/point3d.hxx>
+#include <simgear/scene/tgdb/TileEntry.hxx>
+
+SG_USING_STD(map);
+
+namespace simgear {
+
+// A class to store and manage a pile of tiles
+class TileCache {
+public:
+    typedef map < long, simgear::TileEntry * > 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
+    TileCache();
+
+    // Destructor
+    ~TileCache();
+
+    // Initialize the tile cache subsystem
+    void init( void );
+
+    // Check if the specified "bucket" exists in the cache
+    bool exists( const SGBucket& b ) const;
+
+    // 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 simgear::TileEntry *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 simgear::TileEntry *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 simgear::TileEntry *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( simgear::TileEntry* e );
+};
+
+}
+
+#endif // _TILECACHE_HXX

simgear/scene/tgdb/TileEntry.cxx

@@ -0,0 +1,503 @@
+// 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.
+
+#include <simgear/compiler.h>
+#include <plib/ul.h>
+
+#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 "ReaderWriterSTG.hxx"
+#include "TileEntry.hxx"
+
+SG_USING_STD(string);
+using namespace simgear;
+
+ModelLoadHelper *TileEntry::_modelLoader=0;
+
+namespace {
+osgDB::RegisterReaderWriterProxy<ReaderWriterSTG> g_readerWriterSTGProxy;
+ModelRegistryCallbackProxy<LoadOnlyCallback> g_stgCallbackProxy("stg");
+}
+
+// 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 TileEntry::get_timestamp() const
+{
+    if (_node.valid()) {
+        return (dynamic_cast<TileCullCallback*>(_node->getCullCallback()))
+            ->getTimeStamp();
+    } else
+        return DBL_MAX;
+}
+
+void TileEntry::set_timestamp(double time_ms)
+{
+    if (_node.valid()) {
+        TileCullCallback* cb
+            = dynamic_cast<TileCullCallback*>(_node->getCullCallback());
+        if (cb)
+            cb->setTimeStamp(time_ms);
+    }
+}
+
+// Constructor
+TileEntry::TileEntry ( 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
+TileEntry::~TileEntry ()
+{
+}
+
+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 TileEntry::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 TileEntry::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 TileEntry::obj_load( const string& path,
+                            osg::Group *geometry, bool is_base, const osgDB::ReaderWriter::Options*options)
+{
+    osg::Node* node = osgDB::readNodeFile(path, options);
+    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 TileEntry::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*
+TileEntry::loadTileByName(const string& index_str,
+                          const osgDB::ReaderWriter::Options* options)
+{
+    long tileIndex;
+    {
+        std::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 );
+
+    osgDB::FilePathList path_list=options->getDatabasePathList();
+
+    // 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;
+            }
+        }
+    }
+
+    SGReaderWriterBTGOptions *opt = new SGReaderWriterBTGOptions(*dynamic_cast<const SGReaderWriterBTGOptions *>(options));
+
+    // obj_load() will generate ground lighting for us ...
+    osg::Group* new_tile = new osg::Group;
+
+    if (found_tile_base) {
+        // load tile if found ...
+        opt->setCalcLights(true);
+        obj_load( object_base.str(), new_tile, true, options);
+
+    } 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,
+                        opt->getMatlib(), 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 );
+            opt->setCalcLights(true);
+            obj_load( custom_path.str(), new_tile, false, options);
+
+        } 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 = 0;
+            if(_modelLoader)
+                model = _modelLoader->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(opt->getMatlib(), custom_path.str(), obj->name);
+            else
+                custom_obj = SGMakeRunwaySign(opt->getMatlib(), 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
+TileEntry::addToSceneGraph(osg::Group *terrain_branch)
+{
+    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
+TileEntry::removeFromSceneGraph()
+{
+    SG_LOG( SG_TERRAIN, SG_DEBUG, "disconnecting TileEntry 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 nodes branch parent
+    if ( _node->getNumParents() > 0 ) {
+        // find the first parent (should only be one)
+        osg::Group *parent = _node->getParent( 0 ) ;
+        if( parent ) {
+            parent->removeChild( _node.get() );
+        }
+    }
+}
+

simgear/scene/tgdb/TileEntry.hxx

@@ -0,0 +1,182 @@
+// 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
+
+#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 <osgDB/ReaderWriter>
+#include <osg/Group>
+#include <osg/LOD>
+
+#if defined( sgi )
+#include <strings.h>
+#endif
+
+SG_USING_STD(string);
+SG_USING_STD(vector);
+
+namespace simgear {
+
+class ModelLoadHelper;
+
+/**
+ * A class to encapsulate everything we need to know about a scenery tile.
+ */
+class TileEntry {
+
+public:
+    // this tile's official location in the world
+    SGBucket tile_bucket;
+    std::string tileFileName;
+
+    typedef vector < Point3D > point_list;
+    typedef point_list::iterator point_list_iterator;
+    typedef point_list::const_iterator const_point_list_iterator;
+
+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,
+                          const osgDB::ReaderWriter::Options* options);
+
+    /**
+     * 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;
+
+    static ModelLoadHelper *_modelLoader;
+
+public:
+
+    // Constructor
+    TileEntry( const SGBucket& b );
+
+    // Destructor
+    ~TileEntry();
+
+    static void setModelLoadHelper(ModelLoadHelper *m) { _modelLoader=m; }
+
+    // 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 osgDB::ReaderWriter::Options*);
+    /**
+     * 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 addToSceneGraph( osg::Group *terrain_branch);
+
+    /**
+     * disconnect terrain mesh and ground lighting nodes from scene
+     * graph for this tile.
+     */
+    void removeFromSceneGraph();
+
+	
+    /**
+     * 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; }
+};
+
+class ModelLoadHelper {
+public:
+    virtual osg::Node *loadTileModel(const string& modelPath, bool cacheModel)=0;
+
+};
+
+}
+
+#endif // _TILEENTRY_HXX 

simgear/scene/tgdb/userdata.cxx

@@ -60,7 +60,7 @@ void sgUserDataInit( SGPropertyNode *p ) {
     root_props = p;
 }
 
- osg::Node* sgGetRandomModel(SGMatModel *obj) {
+osg::Node* sgGetRandomModel(SGMatModel *obj) {
    return obj->get_random_model( root_props );
  }