Sanat, You have to use the osgSim class to achieve your objective. In particular, use the method
osgSim::HeightAboveTerrain::computeHeightAboveTerrain(terrain_node, osg::Vec3d(X,Y,Z)) where X,Y,Z is the geocentric coordinates (earth centered) calculated from a given lat,lon,alt. The method to calculate X,Y,Z from a given lat,lon,alt is in the EllipsoidModel class. You can extract the height on terrain from the above HAT calculation to place your models on the terrain surface. The reason why you want to use the osgSim class is that it accounts for VPB pagedLOD databases when determining HAT/HOT and LOS calculations. -Shayne -----Original Message----- From: osg-users-boun...@lists.openscenegraph.org [mailto:osg-users-boun...@lists.openscenegraph.org] On Behalf Of Sanat Talmaki Sent: Friday, April 08, 2011 12:10 PM To: osg-users@lists.openscenegraph.org Subject: [osg-users] Unable to place model on vpb terrain. How To ? Hi, I am trying to place a model on a vpb terrain by supplying the lat-long coordinates. I followed a couple of threads in the forum that suggested to use the CoordinateSystemNode and ellipsoid model. But that didn't work for me (or maybe I am not following it right). I have attached the terrain along with my post. So far this is what I am doing: Code: osg::ref_ptr<osg::Group> root = new osg::Group(); osg::ref_ptr<osg::CoordinateSystemNode> csn = new osg::CoordinateSystemNode(); csn->setEllipsoidModel(new osg::EllipsoidModel()); osg::ref_ptr<osg::Group> terrainGroup = new osg::Group(); //osg::ref_ptr<osg::Node> terrain = osgDB::readNodeFile("NorthCampus6Levels.osg"); osg::ref_ptr<osg::Node> terrain = osgDB::readNodeFile("NorthCampus6LevelsNoCS.osg"); terrainGroup->addChild(terrain); osg::Vec3d m_surface; csn->getEllipsoidModel()->convertLatLongHeightToXYZ(osg::DegreesToRadian s(42.291966f), osg::DegreesToRadians(-83.715645f), 0.0f, double(m_surface.x()),double(m_surface.y()),double(m_surface.z()) ); I tried using a visitor to find the CoordSystNode in my scenegraph but when I checked getEllipsoidModel I got a null. I have used osgEarth in the past and was able to place a model on that. But I presently need to use vpb. If anyone can point me in the right direction, it would be great. Thank You. Sincerely, Sanat ------------------ Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=38336#38336 Attachments: http://forum.openscenegraph.org//files/northcampus6levels_171.osg _______________________________________________ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.or g _______________________________________________ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
