C++ TilePagedLOD::setChildBoundingBoxAndMatrix方法代码示例

//.........这里部分代码省略.........

        // Setup expiration.
        if (_options.minExpiryFrames().isSet())
        {
            plod->setMinimumExpiryFrames(1, *_options.minExpiryFrames());
        }
        
        if (_options.minExpiryTime().isSet())
        {         
            plod->setMinimumExpiryTime(1, *_options.minExpiryTime());
        }      

        if ( _options.rangeMode().value() == osg::LOD::DISTANCE_FROM_EYE_POINT )
        {
            //Compute the min range based on the 2D size of the tile
            GeoExtent extent = model->_tileKey.getExtent();
            double radius = 0.0;
      
            GeoPoint lowerLeft(extent.getSRS(), extent.xMin(), extent.yMin(), 0.0, ALTMODE_ABSOLUTE);
            GeoPoint upperRight(extent.getSRS(), extent.xMax(), extent.yMax(), 0.0, ALTMODE_ABSOLUTE);
            osg::Vec3d ll, ur;
            lowerLeft.toWorld( ll );
            upperRight.toWorld( ur );
            double radiusDiag = (ur - ll).length() / 2.0;

            if (_options.adaptivePolarRangeFactor() == true )
            {
                GeoPoint left(extent.getSRS(), extent.xMin(), extent.yMin()+extent.height()*0.5, 0.0, ALTMODE_ABSOLUTE);
                GeoPoint right(extent.getSRS(), extent.xMax(), extent.yMin()+extent.height()*0.5, 0.0, ALTMODE_ABSOLUTE);
                osg::Vec3d l, r;
                left.toWorld(l);
                right.toWorld(r);
                double radiusHoriz = 1.4142 * (r - l).length() / 2.0;
                
                double lat = model->_tileKey.getExtent().yMin() < 0 ? -model->_tileKey.getExtent().yMax() : model->_tileKey.getExtent().yMin();
                double latRad = osg::DegreesToRadians(lat);

                // mix between diagonal radius and horizontal radius based on latitude
                double t = cos(latRad);
                t = 1.0-(1.0-t)*(1.0-t);    // decelerate t to weight the mix in favor of equator (diag radius)
                radius = t*radiusDiag + (1.0-t)*radiusHoriz;
            }
            else
            {
                radius = radiusDiag;
            }
          
            float minRange = radius;

            plod->setRange( 0, minRange, FLT_MAX );
            plod->setRange( 1, 0, minRange );
            plod->setRangeMode( osg::LOD::DISTANCE_FROM_EYE_POINT );
        }
        else
        {
            // the *2 is because we page in 4-tile sets, not individual tiles.
            float size = 2.0f * _options.tilePixelSize().value();
            plod->setRange( 0, 0.0f, size );
            plod->setRange( 1, size, FLT_MAX );
            plod->setRangeMode( osg::LOD::PIXEL_SIZE_ON_SCREEN );
        }
        
        // Install a tile-aligned bounding box in the pager node itself so we can do
        // visibility testing before paging in subtiles.
        plod->setChildBoundingBoxAndMatrix(
            1,
            tileNode->getTerrainBoundingBox(),
            tileNode->getMatrix() );

        // DBPager will set a priority based on the ratio range/maxRange.
        // This will offset that number with a full LOD #, giving LOD precedence.
        // Experimental.
        //plod->setPriorityScale( 1, model->_tileKey.getLOD()+1 );

#if USE_FILELOCATIONCALLBACK
        osgDB::Options* options = plod->getOrCreateDBOptions();
        options->setFileLocationCallback( new FileLocationCallback() );
#endif
        
        result = plod;

        // this one rejects back-facing tiles:
        if ( _frame.getMapInfo().isGeocentric() && _options.clusterCulling() == true )
        {
            osg::HeightField* hf =
                model->_elevationData.getHeightField();

            result->addCullCallback( HeightFieldUtils::createClusterCullingCallback(
                hf,
                tileNode->getKey().getProfile()->getSRS()->getEllipsoid(),
                *_options.verticalScale() ) );
        }
    }
    else
    {
        result = tileNode.release();
    }

    return result;
}

osg::Node*
SingleKeyNodeFactory::createTile(TileModel*        model,
                                 bool              setupChildrenIfNecessary,
                                 ProgressCallback* progress)
{
#ifdef EXPERIMENTAL_TILE_NODE_CACHE
    osg::ref_ptr<TileNode> tileNode;
    TileNodeCache::Record rec;
    cache.get(model->_tileKey, rec);
    if ( rec.valid() )
    {
        tileNode = rec.value().get();
    }
    else
    {
        tileNode = _modelCompiler->compile( model, _frame );
        cache.insert(model->_tileKey, tileNode);
    }
#else
    // compile the model into a node:
    TileNode* tileNode = _modelCompiler->compile(model, _frame, progress);
    tileNode->setEngineUID( _engineUID );
#endif

    // see if this tile might have children.
    bool prepareForChildren =
        setupChildrenIfNecessary &&
        model->_tileKey.getLOD() < *_options.maxLOD();

    osg::Node* result = 0L;

    if ( prepareForChildren )
    {
        osg::BoundingSphere bs = tileNode->getBound();
        TilePagedLOD* plod = new TilePagedLOD( _engineUID, _liveTiles, _deadTiles );
        plod->setCenter  ( bs.center() );
        plod->addChild   ( tileNode );
        plod->setFileName( 1, Stringify() << tileNode->getKey().str() << "." << _engineUID << ".osgearth_engine_mp_tile" );

        if ( _options.rangeMode().value() == osg::LOD::DISTANCE_FROM_EYE_POINT )
        {
            //Compute the min range based on the 2D size of the tile
            GeoExtent extent = model->_tileKey.getExtent();
            GeoPoint lowerLeft(extent.getSRS(), extent.xMin(), extent.yMin(), 0.0, ALTMODE_ABSOLUTE);
            GeoPoint upperRight(extent.getSRS(), extent.xMax(), extent.yMax(), 0.0, ALTMODE_ABSOLUTE);
            osg::Vec3d ll, ur;
            lowerLeft.toWorld( ll );
            upperRight.toWorld( ur );
            double radius = (ur - ll).length() / 2.0;
            float minRange = (float)(radius * _options.minTileRangeFactor().value());

            plod->setRange( 0, minRange, FLT_MAX );
            plod->setRange( 1, 0, minRange );
            plod->setRangeMode( osg::LOD::DISTANCE_FROM_EYE_POINT );
        }
        else
        {
            // the *2 is because we page in 4-tile sets, not individual tiles.
            float size = 2.0f * _options.tilePixelSize().value();
            plod->setRange( 0, 0.0f, size );
            plod->setRange( 1, size, FLT_MAX );
            plod->setRangeMode( osg::LOD::PIXEL_SIZE_ON_SCREEN );
        }
        
        // Install a tile-aligned bounding box in the pager node itself so we can do
        // visibility testing before paging in subtiles.
        plod->setChildBoundingBoxAndMatrix(
            1,
            tileNode->getTerrainBoundingBox(),
            tileNode->getMatrix() );

        // DBPager will set a priority based on the ratio range/maxRange.
        // This will offset that number with a full LOD #, giving LOD precedence.
        // Experimental.
        //plod->setPriorityScale( 1, model->_tileKey.getLOD()+1 );

#if USE_FILELOCATIONCALLBACK
        osgDB::Options* options = plod->getOrCreateDBOptions();
        options->setFileLocationCallback( new FileLocationCallback() );
#endif
        
        result = plod;

        // this one rejects back-facing tiles:
        if ( _frame.getMapInfo().isGeocentric() && _options.clusterCulling() == true )
        {

#if 1
            osg::HeightField* hf =
                model->_elevationData.getHeightField();

            result->addCullCallback( HeightFieldUtils::createClusterCullingCallback(
                hf,
                tileNode->getKey().getProfile()->getSRS()->getEllipsoid(),
                *_options.verticalScale() ) );
#else
            // This works, but isn't quite as tight at the cluster culler.
            // Re-evaluate down the road.
            result->addCullCallback( new HorizonTileCuller(
                _frame.getMapInfo().getSRS(),
//.........这里部分代码省略.........

TileNode*
TileGroupFactory::createTileNodeGraph(TerrainTileModel* model,
                                      bool              setupChildrenIfNecessary,
                                      ProgressCallback* progress)
{
    // TODO: fix this
    const unsigned tileSize = 17;

    // Build the surface node.
    SurfaceNodeFactory factory(model, _frame, _renderBindings, _geometryPool, tileSize, _options);
    SurfaceNode* surfaceNode = factory.createSurfaceNode();

    surfaceNode->setEngineUID( _terrainEngine->getUID() );

    // see if this tile might have children.
    bool prepareForChildren =
        setupChildrenIfNecessary &&
        model->getKey().getLOD() < *_options.maxLOD();
    
    // Build the Tile Node that will hold all the textures and texture matrices.
    TileNode* tileNode = createTileNode(
        model,
        progress );

    // Build the paging node that will load subtiles, if necessary:
    if ( prepareForChildren )
    {
        osg::BoundingSphere bs = surfaceNode->getBound();
        TilePagedLOD* plod = new TilePagedLOD( _terrainEngine->getUID(), _liveTiles, _deadTiles );
        plod->setCenter  ( bs.center() );
        plod->addChild   ( surfaceNode );
        plod->setFileName( 1, Stringify() 
            << model->getKey().str()
            << "." << _terrainEngine->getUID()
            << ".osgearth_engine_mp_tile" );

        if ( _options.rangeMode().value() == osg::LOD::DISTANCE_FROM_EYE_POINT )
        {
            //Compute the min range based on the 2D size of the tile
            GeoExtent extent = model->getKey().getExtent();
            GeoPoint lowerLeft(extent.getSRS(), extent.xMin(), extent.yMin(), 0.0, ALTMODE_ABSOLUTE);
            GeoPoint upperRight(extent.getSRS(), extent.xMax(), extent.yMax(), 0.0, ALTMODE_ABSOLUTE);
            osg::Vec3d ll, ur;
            lowerLeft.toWorld( ll );
            upperRight.toWorld( ur );
            double radius = (ur - ll).length() / 2.0;
            float minRange = (float)(radius * _options.minTileRangeFactor().value());

            plod->setRange( 0, minRange, FLT_MAX );
            plod->setRange( 1, 0, minRange );
            plod->setRangeMode( osg::LOD::DISTANCE_FROM_EYE_POINT );
        }
        else
        {
            plod->setRange( 0, 0.0f, _options.tilePixelSize().value() );
            plod->setRange( 1, _options.tilePixelSize().value(), FLT_MAX );
            plod->setRangeMode( osg::LOD::PIXEL_SIZE_ON_SCREEN );
        }
        
#if 0 // TODO: reinstate this!

        // Install a tile-aligned bounding box in the pager node itself so we can do
        // visibility testing before paging in subtiles.
        plod->setChildBoundingBoxAndMatrix(
            1,
            surfaceNode->getTerrainBoundingBox(),
            surfaceNode->getLocalToWorldMatrix() );
#endif

#if USE_FILELOCATIONCALLBACK
        osgDB::Options* options = plod->getOrCreateDBOptions();
        options->setFileLocationCallback( new FileLocationCallback() );
#endif
        
        tileNode->addChild( plod );

        // Install a callback to reject back-facing tiles.
        if ( _frame.getMapInfo().isGeocentric() && _options.clusterCulling() == true )
        {
            const osg::HeightField* heightField = model->elevationModel()->getHeightField();
            if ( heightField )
            {
                tileNode->addCullCallback( HeightFieldUtils::createClusterCullingCallback(
                    heightField,
                    tileNode->getKey().getProfile()->getSRS()->getEllipsoid(),
                    *_options.verticalScale() ) );
            }
        }
    }
    else
    {
        tileNode->addChild( surfaceNode );
    }

    return tileNode;
}