Hi Robert Thanks a lot, was starting to get at this but using a more primitive approach of running through all the children of the node that I did get.
Will try to implement your method. Brgs. Ralf Stokholm 2009/4/2 Robert Osfield <[email protected]>: > Hi Ralf, > > You'll need to write a custom NodeVisitor that traverses through the loaded > scene graph and picks out the TerrainTile using dyanmic cast. It just so > happens that I'm actually working on a ReadFileCallback/custom Visitor that > does pick out all the TerrainTile's in a subgraph (there will typically be > one, two or four due to the quad tree structure generated by VPB.) > > The visitor looks like: > > class FindTerrainTileVisitor : public osg::NodeVisitor > { > public: > FindTerrainTileVisitor(): > osg::NodeVisitor(osg::NodeVisitor::TRAVERSE_ALL_CHILDREN) > { > } > > void reset() > { > _terrainTiles.clear(); > } > > void apply(osg::Group& group) > { > osgTerrain::TerrainTile* terrainTile = > dynamic_cast<osgTerrain::TerrainTile*>(&group); > if (terrainTile) > { > _terrainTiles.push_back(terrainTile); > } > else > { > traverse(group); > } > } > > typedef std::list< osg::ref_ptr<osgTerrain::TerrainTile> > TerrainTiles; > TerrainTiles _terrainTiles; > }; > > The custom ReadFileCallback's readNode method looks like: > > virtual osgDB::ReaderWriter::ReadResult readNode(const std::string& > filename, const osgDB::ReaderWriter::Options* options) > { > osg::notify(osg::NOTICE)<<"Loading tile "<<filename<<std::endl; > osgDB::ReaderWriter::ReadResult result = > osgDB::Registry::instance()->readNodeImplementation(filename,options); > if (result.validNode()) > { > FindTerrainTileVisitor fttv; > result.getNode()->accept(fttv); > for(FindTerrainTileVisitor::TerrainTiles::iterator itr = > fttv._terrainTiles.begin(); > itr != fttv._terrainTiles.end(); > ++itr) > { > osgTerrain::TerrainTile* terrainTile = itr->get(); > ///.... my stuff omitted, put your stuff here > } > } > } > > > Robert. > > On Thu, Apr 2, 2009 at 1:05 PM, Ralf Stokholm <[email protected]> > wrote: >> >> Hi List >> >> Im trying to get the heightfiled data from a VPB terrain using >> ReadFileCallback. >> >> I use the code from readfile callback like this. >> >> class MyReadFileCallback : public osgDB::Registry::ReadFileCallback >> { >> public: >> virtual osgDB::ReaderWriter::ReadResult readNode(const >> std::string& fileName, const osgDB::ReaderWriter::Options* options) >> { >> // note when calling the Registry to do the read you have to >> call readNodeImplementation NOT readNode, as this will >> // cause on infinite recusive loop. >> osgDB::ReaderWriter::ReadResult result = >> osgDB::Registry::instance()->readNodeImplementation(fileName,options); >> if (result.validHeightField()) >> { >> LOG_ERROR("Found a valid HeightField"); >> } >> return result; >> } >> }; >> >> The idea was simply to see if I had the heightfield available, but >> even though I have verified that it gets called it is never a valid >> heightfield. >> >> This is on a terrain build using VPB with the --TERRAIN option. >> >> Shouldent I be able to get the heightfieldnodes? >> >> Brgs. >> >> Ralf Stokholm >> _______________________________________________ >> osg-users mailing list >> [email protected] >> http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org > > > _______________________________________________ > osg-users mailing list > [email protected] > http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org > > _______________________________________________ osg-users mailing list [email protected] http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
