Hi Lucie, On Wed, Sep 29, 2010 at 10:43 AM, lucie lemonnier <[email protected]> wrote: > I understood that the XYZ are in Earth Center Earth Fixed coordinates. > So is it normal that X,Y are calculated based on height?
I'm a bit confused by your question, in ECEF the coordinate is always XYZ, one doesn't ever just consider XY, this would just be a projection of the each onto a flat cross section through the side of the each, not sure what use this would be. > In fact, I put a latitude, longitude and height on a model, I use > osg::EllipsoidModel::convertLatLongHeightToXYZ to obtain the position x,y,z > and I transform my point with the MatrixTransforms applied on the terrain > model and I place my model with the transformed point. > Is it the step to be followed? One normally uses a transform node to enable one to place local coordinates into the ECEF coordinate frame without lose of precision when computing intersections and doing rendering. The osgTerrain NodeKit uses transforms to avoid numerical issues, so have a look at src/osgTerrain/GeometryTechnique.cpp it see how it computes it's transform and local coordinates. Robert. _______________________________________________ osg-users mailing list [email protected] http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
