On Dec 7, 2007 6:51 AM, J.P. Delport <[EMAIL PROTECTED]> wrote: > Hi all, > > just to add that I also get clipping with the new modes from certain > viewing angles. Sometimes the clipped edges rotate as the view moves and > some parts jump in and out (dunno if this makes sense). I've thought > about trying to debug it, but I have no idea where to start, the shaders > look complex. Any documentation on the new modes or any related > documentation on the methods used?
Well there is the code... but I'm afraid that's the OSG specific docs on OverlayNode we have. The view dependent overlay codes are similar in concept to view dependent shadow map algorithms like perspective shadow maps, the papers of this topic will give you an overview but won't be enough to guide you through the details. One the OSG side it has to contend with large model support (i.e. whole earth models) that academic papers don't ever discuss so there are deviations, there is also the aspect of getting it to work with a general purpose scene graph - real implementations often are far more complex than demo ones with constraints on the database. As to what the bugs are.. my guess associated with compute the tight bound on the overlay geometry, the intersection of this volume with the view frustum and the intersection in turn of the projection of the intersected volume with the decorated scene. The shaders are probably OK, save for some GLSL implementation not being up to scratch. Robert. Robert. _______________________________________________ osg-users mailing list [email protected] http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
