Thanks Frederic - as you say, for the case of a square, you'd expect the bounding sphere diameter to contain the bounding box - ie. in this case the square itself.
The problem I'm having is trying to relate the pixelSize() returned value to the pixel size of the square's diagonal as measured on the screen. I expected them to be identical, but they don't correlate at all. Is the returned value of pixelSize() for a bounding sphere an area/ diameter? Either way it doesn't seem to equate to the measurements I make from doing a screen grab and counting pixels. I have a feeling I'm missing some kind of transformation between computing the pixelSize and relating that to the measurements made on the screen. Paul ------------------ Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=30607#30607 _______________________________________________ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org