void GlobePlugin::elevationLayersChanged()
{
  if ( mIsGlobeRunning )
  {
    QgsDebugMsg( "elevationLayersChanged: Globe Running, executing" );
    osg::ref_ptr<Map> map = mMapNode->getMap();

    if ( map->getNumElevationLayers() > 1 )
    {
      mOsgViewer->getDatabasePager()->clear();
    }

    // Remove elevation layers
    ElevationLayerVector list;
    map->getElevationLayers( list );
    for ( ElevationLayerVector::iterator i = list.begin(); i != list.end(); ++i )
    {
      map->removeElevationLayer( *i );
    }

    // Add elevation layers
    QSettings settings;
    QString cacheDirectory = settings.value( "cache/directory", QgsApplication::qgisSettingsDirPath() + "cache" ).toString();
    QTableWidget* table = mSettingsDialog->elevationDatasources();
    for ( int i = 0; i < table->rowCount(); ++i )
    {
      QString type = table->item( i, 0 )->text();
      //bool cache = table->item( i, 1 )->checkState();
      QString uri = table->item( i, 2 )->text();
      ElevationLayer* layer = 0;

      if ( "Raster" == type )
      {
        GDALOptions options;
        options.url() = uri.toStdString();
        layer = new osgEarth::ElevationLayer( uri.toStdString(), options );
      }
      else if ( "TMS" == type )
      {
        TMSOptions options;
        options.url() = uri.toStdString();
        layer = new osgEarth::ElevationLayer( uri.toStdString(), options );
      }
      map->addElevationLayer( layer );

      //if ( !cache || type == "Worldwind" ) layer->setCache( 0 ); //no tms cache for worldwind (use worldwind_cache)
    }
#if OSGEARTH_VERSION_GREATER_OR_EQUAL( 2, 5, 0 )
    double scale = QgsProject::instance()->readDoubleEntry( "Globe-Plugin", "/verticalScale", 1 );
    setVerticalScale( scale );
#endif
  }
  else
  {
    QgsDebugMsg( "layersChanged: Globe NOT running, skipping" );
    return;
  }
}

/**
 * How to create a simple osgEarth map and display it.
 */
int
main(int argc, char** argv)
{
    osg::ArgumentParser arguments(&argc,argv);

    // create the empty map.
    Map* map = new Map();

    // add a TMS imagery layer:
    TMSOptions imagery;
    imagery.url() = "http://readymap.org/readymap/tiles/1.0.0/22/";
    map->addLayer( new ImageLayer("ReadyMap Imagery", imagery) );

    // add a TMS elevation layer:
    TMSOptions elevation;
    elevation.url() = "http://readymap.org/readymap/tiles/1.0.0/116/";
    map->addLayer( new ElevationLayer("ReadyMap Elevation", elevation) );
   
    // Load command line arguments as videos.
    for(int pos=1;pos<arguments.argc();++pos)
    {
        if (!arguments.isOption(pos))
        {
            std::string filename = arguments[ pos ];
            OE_NOTICE << "Loading " << filename << std::endl;
            VideoLayerOptions opt;
            opt.url() = filename;
            VideoLayer* layer = new VideoLayer(opt);
            map->addLayer(layer);
        }
    }

    // make the map scene graph:
    MapNode* node = new MapNode( map );

    // initialize a viewer:
    osgViewer::Viewer viewer(arguments);
    viewer.setCameraManipulator( new EarthManipulator );
    viewer.setSceneData( node );

    // add some stock OSG handlers:
    viewer.addEventHandler(new osgViewer::StatsHandler());
    viewer.addEventHandler(new osgViewer::WindowSizeHandler());
    viewer.addEventHandler(new osgViewer::ThreadingHandler());
    viewer.addEventHandler(new osgViewer::LODScaleHandler());
    viewer.addEventHandler(new osgGA::StateSetManipulator(viewer.getCamera()->getOrCreateStateSet()));
    viewer.addEventHandler(new osgViewer::HelpHandler(arguments.getApplicationUsage()));

    return viewer.run();
}

void GlobePlugin::setBaseMap( QString url )
{
  if ( mMapNode )
  {
    mMapNode->getMap()->removeImageLayer( mBaseLayer );
    if ( url.isNull() )
    {
      mBaseLayer = 0;
    }
    else
    {
      TMSOptions imagery;
      imagery.url() = url.toStdString();
      mBaseLayer = new ImageLayer( "Imagery", imagery );
      mMapNode->getMap()->insertImageLayer( mBaseLayer, 0 );
    }
  }
}

//.........这里部分代码省略.........

    // establish the output path of the earth file, if applicable:
    std::string outEarthFile = osgDB::concatPaths( rootFolder, osgDB::getSimpleFileName( outEarth ) );

    // package any image layers that are enabled:
    ImageLayerVector imageLayers;
    map->getImageLayers( imageLayers );

    unsigned counter = 0;

    for( ImageLayerVector::iterator i = imageLayers.begin(); i != imageLayers.end(); ++i, ++counter )
    {
        ImageLayer* layer = i->get();
        if( layer->getImageLayerOptions().enabled() == true )
        {
            std::string layerFolder = toLegalFileName( layer->getName() );
            if( layerFolder.empty() )
                layerFolder = Stringify() << "image_layer_" << counter;

            if( verbose )
            {
                OE_NOTICE << LC << "Packaging image layer \"" << layerFolder << "\"" << std::endl;
            }

            osg::ref_ptr< ConsoleProgressCallback > progress = new ConsoleProgressCallback();
            std::string layerRoot = osgDB::concatPaths( rootFolder, layerFolder );
            TMSPackager::Result r = packager.package( layer, layerRoot, progress, extension );
            if( r.ok )
            {
                // save to the output map if requested:
                if( outMap.valid() )
                {
                    // new TMS driver info:
                    TMSOptions tms;
                    tms.url() = URI(
                        osgDB::concatPaths( layerFolder, "tms.xml" ),
                        outEarthFile );

                    ImageLayerOptions layerOptions( layer->getName(), tms );
                    layerOptions.mergeConfig( layer->getInitialOptions().getConfig( true ) );
                    layerOptions.cachePolicy() = CachePolicy::NO_CACHE;

                    outMap->addImageLayer( new ImageLayer( layerOptions ) );
                }
            }
            else
            {
                OE_WARN << LC << r.message << std::endl;
            }
        }
        else if( verbose )
        {
            OE_NOTICE << LC << "Skipping disabled layer \"" << layer->getName() << "\"" << std::endl;
        }
    }

    // package any elevation layers that are enabled:
    counter = 0;
    ElevationLayerVector elevationLayers;
    map->getElevationLayers( elevationLayers );

    for( ElevationLayerVector::iterator i = elevationLayers.begin(); i != elevationLayers.end(); ++i, ++counter )
    {
        ElevationLayer* layer = i->get();
        if( layer->getElevationLayerOptions().enabled() == true )
        {

//.........这里部分代码省略.........
        }
        else
        {
            std::cout << "Failed to find an elevation layer at index " << elevationLayerIndex << std::endl;
            return 1;
        }
    }
    else
    {        
        // Package all the ImageLayer's
        for (unsigned int i = 0; i < map->getNumImageLayers(); i++)
        {            
            ImageLayer* layer = map->getImageLayerAt(i);        
            OE_NOTICE << "Packaging " << layer->getName() << std::endl;
            osg::Timer_t start = osg::Timer::instance()->tick();
            packager.run(layer, map);
            osg::Timer_t end = osg::Timer::instance()->tick();
            if (verbose)
            {
                OE_NOTICE << "Completed seeding layer " << layer->getName() << " in " << prettyPrintTime( osg::Timer::instance()->delta_s( start, end ) ) << std::endl;
            }                

            if (writeXML)
            {
                packager.writeXML(layer, map);
            }

            // save to the output map if requested:
            if( outMap.valid() )
            {
                std::string layerFolder = toLegalFileName( packager.getLayerName() );

                // new TMS driver info:
                TMSOptions tms;
                tms.url() = URI(
                    osgDB::concatPaths( layerFolder, "tms.xml" ),
                    outEarthFile );

                ImageLayerOptions layerOptions( packager.getLayerName(), tms );
                layerOptions.mergeConfig( layer->getInitialOptions().getConfig( true ) );
                layerOptions.cachePolicy() = CachePolicy::NO_CACHE;

                outMap->addImageLayer( new ImageLayer( layerOptions ) );
            }
        }    

        // Package all the ElevationLayer's
        for (unsigned int i = 0; i < map->getNumElevationLayers(); i++)
        {            
            ElevationLayer* layer = map->getElevationLayerAt(i);        
            OE_NOTICE << "Packaging " << layer->getName() << std::endl;
            osg::Timer_t start = osg::Timer::instance()->tick();
            packager.run(layer, map);
            osg::Timer_t end = osg::Timer::instance()->tick();
            if (verbose)
            {
                OE_NOTICE << "Completed seeding layer " << layer->getName() << " in " << prettyPrintTime( osg::Timer::instance()->delta_s( start, end ) ) << std::endl;
            }      
            if (writeXML)
            {
                packager.writeXML(layer, map);
            }

            // save to the output map if requested:
            if( outMap.valid() )
            {

// Creates a visible imagery layer that we will modulate.
ImageLayer* createImageryLayer()
{
    TMSOptions tms;
    tms.url() = "http://readymap.org/readymap/tiles/1.0.0/7/";
    return new ImageLayer( "imagery", tms );
}

void GlobePlugin::setupMap()
{
  QSettings settings;
  /*
  QString cacheDirectory = settings.value( "cache/directory", QgsApplication::qgisSettingsDirPath() + "cache" ).toString();
  TMSCacheOptions cacheOptions;
  cacheOptions.setPath( cacheDirectory.toStdString() );
  */

  MapOptions mapOptions;
  //mapOptions.cache() = cacheOptions;
  osgEarth::Map *map = new osgEarth::Map( mapOptions );

  //Default image layer
  /*
  GDALOptions driverOptions;
  driverOptions.url() = QDir::cleanPath( QgsApplication::pkgDataPath() + "/globe/world.tif" ).toStdString();
  ImageLayerOptions layerOptions( "world", driverOptions );
  map->addImageLayer( new osgEarth::ImageLayer( layerOptions ) );
  */
  TMSOptions imagery;
  imagery.url() = "http://readymap.org/readymap/tiles/1.0.0/7/";
  map->addImageLayer( new ImageLayer( "Imagery", imagery ) );

  MapNodeOptions nodeOptions;
  //nodeOptions.proxySettings() =
  //nodeOptions.enableLighting() = false;

  //LoadingPolicy loadingPolicy( LoadingPolicy::MODE_SEQUENTIAL );
  TerrainOptions terrainOptions;
  //terrainOptions.loadingPolicy() = loadingPolicy;
  terrainOptions.compositingTechnique() = TerrainOptions::COMPOSITING_MULTITEXTURE_FFP;
  //terrainOptions.lodFallOff() = 6.0;
  nodeOptions.setTerrainOptions( terrainOptions );

  // The MapNode will render the Map object in the scene graph.
  mMapNode = new osgEarth::MapNode( map, nodeOptions );

  mRootNode = new osg::Group();
  mRootNode->addChild( mMapNode );

  // Add layers to the map
  imageLayersChanged();
  elevationLayersChanged();

  // model placement utils
#ifdef HAVE_OSGEARTH_ELEVATION_QUERY
#else
  mElevationManager = new osgEarth::Util::ElevationManager( mMapNode->getMap() );
  mElevationManager->setTechnique( osgEarth::Util::ElevationManager::TECHNIQUE_GEOMETRIC );
  mElevationManager->setMaxTilesToCache( 50 );

  mObjectPlacer = new osgEarth::Util::ObjectPlacer( mMapNode );

  // place 3D model on point layer
  if ( mSettingsDialog->modelLayer() && !mSettingsDialog->modelPath().isEmpty() )
  {
    osg::Node* model = osgDB::readNodeFile( mSettingsDialog->modelPath().toStdString() );
    if ( model )
    {
      QgsVectorLayer* layer = mSettingsDialog->modelLayer();
      QgsFeatureIterator fit = layer->getFeatures( QgsFeatureRequest().setSubsetOfAttributes( QgsAttributeList() ) ); //TODO: select only visible features
      QgsFeature feature;
      while ( fit.nextFeature( feature ) )
      {
        QgsPoint point = feature.geometry()->asPoint();
        placeNode( model, point.y(), point.x() );
      }
    }
  }
#endif

}

//.........这里部分代码省略.........
    {
        packager.getTileVisitor()->addExtent( osgEarth::GeoExtent(map->getProfile()->getSRS(), bounds[i]));
    }
    packager.setExtension(extension);  
    packager.setOverwrite(overwrite);
    packager.getTileVisitor()->setProgressCallback( _progress.get() );
    packager.getTileVisitor()->setMaxLevel(_maxLevel);

    // Compute the total number of layers we are going to operate on.
    unsigned int totalLayers = map->getNumImageLayers() + map->getNumElevationLayers();  

    unsigned int layerNum = 1;

    // Package each image layer
    for (unsigned int i = 0; i < map->getNumImageLayers(); i++)
    {            
        // Don't continue if the export has been canceled
        if (_progress->isCanceled())
        {
            break;
        }
        osg::ref_ptr< ImageLayer > layer = map->getImageLayerAt(i);      
        std::stringstream buf;
        buf << "Packaging " << layer->getName() << " (" << layerNum << " of " << totalLayers << ")";
        OE_NOTICE << buf.str() << std::endl;
        _progress->setStatus(buf.str());
        packager.run(layer.get(), map);
        packager.writeXML(layer.get(), map);
        if (outMap)
        {
            std::string layerFolder = toLegalFileName( packager.getLayerName() );

            // new TMS driver info:
            TMSOptions tms;
            tms.url() = URI(
                osgDB::concatPaths( layerFolder, "tms.xml" ),
                outEarthFile );

            ImageLayerOptions layerOptions( packager.getLayerName(), tms );
            layerOptions.mergeConfig( layer->getInitialOptions().getConfig( true ) );
            layerOptions.cachePolicy() = CachePolicy::NO_CACHE;

            outMap->addImageLayer( new ImageLayer( layerOptions ) );
        }
        layerNum++;
    }

    // Package each elevation layer
    for (unsigned int i = 0; i < map->getNumElevationLayers(); i++)
    {
        // Don't continue if the export has been canceled
        if (_progress->isCanceled())
        {
            break;
        }

        osg::ref_ptr< ElevationLayer > layer = map->getElevationLayerAt(i);      
        std::stringstream buf;
        buf << "Packaging " << layer->getName() << " (" << layerNum << " of " << totalLayers << ")";
        OE_NOTICE << buf.str() << std::endl;
        _progress->setStatus(buf.str());
        packager.run(layer.get(), map);
        packager.writeXML(layer.get(), map);

        if( outMap.valid() )
        {

/**
 * This code example effectively duplicates the "boston.earth" sample,
 * demonstrating how to create a 3D city model in osgEarth.
 *
 * Run this from the tests folder.
 */
int
main(int argc, char** argv)
{
    osg::ArgumentParser arguments(&argc,argv);

    // create the map.
    Map* map = new Map();

    // add a TMS imagery layer:
    TMSOptions imagery;
    imagery.url() = "http://readymap.org/readymap/tiles/1.0.0/22/";
    map->addImageLayer( new ImageLayer("ReadyMap imagery", imagery) );

    // create a feature source to load the building footprint shapefile.
    OGRFeatureOptions feature_opt;
    feature_opt.name() = "buildings";
    feature_opt.url() = "../data/boston_buildings_utm19.shp";
    feature_opt.buildSpatialIndex() = true;
    
    // a style for the building data:
    Style buildingStyle;
    buildingStyle.setName( "default" );

    ExtrusionSymbol* extrusion = buildingStyle.getOrCreate<ExtrusionSymbol>();
    extrusion->heightExpression() = NumericExpression( "3.5 * max( [story_ht_], 1 )" );
    extrusion->flatten() = true;
    extrusion->wallStyleName() = "building-wall";
    extrusion->roofStyleName() = "building-roof";

    // a style for the wall textures:
    Style wallStyle;
    wallStyle.setName( "building-wall" );
    SkinSymbol* wallSkin = wallStyle.getOrCreate<SkinSymbol>();
    wallSkin->libraryName() = "us_resources";
    wallSkin->addTag( "building" );
    wallSkin->randomSeed() = 1;

    // a style for the rooftop textures:
    Style roofStyle;
    roofStyle.setName( "building-roof" );
    SkinSymbol* roofSkin = roofStyle.getOrCreate<SkinSymbol>();
    roofSkin->libraryName() = "us_resources";
    roofSkin->addTag( "rooftop" );
    roofSkin->randomSeed() = 1;
    roofSkin->isTiled() = true;

    // assemble a stylesheet and add our styles to it:
    StyleSheet* styleSheet = new StyleSheet();
    styleSheet->addStyle( buildingStyle );
    styleSheet->addStyle( wallStyle );
    styleSheet->addStyle( roofStyle );
    
    // load a resource library that contains the building textures.
    ResourceLibrary* reslib = new ResourceLibrary( "us_resources", "../data/resources/textures_us/catalog.xml" );
    styleSheet->addResourceLibrary( reslib );

    // set up a paging layout for incremental loading.
    FeatureDisplayLayout layout;
    layout.tileSizeFactor() = 45.0;
    layout.addLevel( FeatureLevel(0.0f, 20000.0f) );

    // create a model layer that will render the buildings according to our style sheet.
    FeatureGeomModelOptions fgm_opt;
    fgm_opt.featureOptions() = feature_opt;
    fgm_opt.styles() = styleSheet;
    fgm_opt.layout() = layout;

    map->addModelLayer( new ModelLayer( "buildings", fgm_opt ) );


    // initialize a viewer:
    osgViewer::Viewer viewer(arguments);
    EarthManipulator* manip = new EarthManipulator();
    viewer.setCameraManipulator( manip );

    // make the map scene graph:
    osg::Group* root = new osg::Group();
    viewer.setSceneData( root );

    MapNode* mapNode = new MapNode( map );
    root->addChild( mapNode );
    
    // Process cmdline args
    MapNodeHelper helper;
    helper.configureView( &viewer );
    helper.parse(mapNode, arguments, &viewer, root, new LabelControl("City Demo"));

    // zoom to a good startup position
    manip->setViewpoint( Viewpoint(-71.0763, 42.34425, 0, 24.261, -21.6, 3450.0), 5.0 );

    viewer.getDatabasePager()->setDoPreCompile( true );
    viewer.getCamera()->addCullCallback( new AutoClipPlaneCullCallback(mapNode) );

    return viewer.run();
//.........这里部分代码省略.........

//.........这里部分代码省略.........
          tasks.push_back(task);
          taskCount++;
      }
  }

  // package any elevation layers that are enabled and visible
  ElevationLayerVector elevationLayers;
  map->getElevationLayers( elevationLayers );

  int elevCount = 0;
  for( ElevationLayerVector::iterator i = elevationLayers.begin(); i != elevationLayers.end(); ++i, ++elevCount )
  {
      ElevationLayer* layer = i->get();
      if ( layer->getEnabled() && layer->getVisible() )
      {
          std::string layerFolder = toLegalFileName( layer->getName() );
          if ( layerFolder.empty() )
              layerFolder = Stringify() << "elevation_layer_" << elevCount;

          ParallelTask<PackageLayer>* task = new ParallelTask<PackageLayer>( &semaphore );
          task->init(map, layer, options, rootFolder, layerFolder, true, overwrite, _keepEmpties, _maxLevel, extension, bounds);
          task->setProgressCallback(new PackageLayerProgressCallback(this));
          tasks.push_back(task);
          taskCount++;
      }
  }


  // Run all the tasks in parallel
  _totalTasks = taskCount;
  _completedTasks = 0;

  semaphore.reset( _totalTasks );

  for( TaskRequestVector::iterator i = tasks.begin(); i != tasks.end(); ++i )
        _taskService->add( i->get() );

  // Wait for them to complete
  semaphore.wait();


  // Add successfully packaged layers to the new map object and
  // write out the .earth file (if requested)
  if (outMap.valid())
  {
    for( TaskRequestVector::iterator i = tasks.begin(); i != tasks.end(); ++i )
    {
      PackageLayer* p = dynamic_cast<PackageLayer*>(i->get());
      if (p)
      {
        if (p->_packageResult.ok)
        {
          TMSOptions tms;
          tms.url() = URI(osgDB::concatPaths(p->_layerFolder, "tms.xml"), outEarthFile );

          if (p->_imageLayer.valid())
          {
            ImageLayerOptions layerOptions( p->_imageLayer->getName(), tms );
            layerOptions.mergeConfig( p->_imageLayer->getInitialOptions().getConfig(true) );
            layerOptions.cachePolicy() = CachePolicy::NO_CACHE;

            outMap->addImageLayer( new ImageLayer(layerOptions) );
          }
          else
          {
            ElevationLayerOptions layerOptions( p->_elevationLayer->getName(), tms );
            layerOptions.mergeConfig( p->_elevationLayer->getInitialOptions().getConfig(true) );
            layerOptions.cachePolicy() = CachePolicy::NO_CACHE;

            outMap->addElevationLayer( new ElevationLayer(layerOptions) );
          }
        }
        else
        {
          OE_WARN << LC << p->_packageResult.message << std::endl;
        }
      }
    }
  }

  if ( outMap.valid() )
  {
      MapNodeOptions outNodeOptions = mapNode->getMapNodeOptions();
      osg::ref_ptr<MapNode> outMapNode = new MapNode(outMap.get(), outNodeOptions);
      if ( !osgDB::writeNodeFile(*outMapNode.get(), outEarthFile) )
      {
          OE_WARN << LC << "Error writing earth file to \"" << outEarthFile << "\"" << std::endl;
      }
      else
      {
          OE_NOTICE << LC << "Wrote earth file to \"" << outEarthFile << "\"" << std::endl;
      }
  }


  // Mark the progress callback as completed
  if (_progress.valid()) _progress->onCompleted();

  return elevCount + imageCount;
}