I checked the source code of OSG and found that the related function was introduced in 2012/2/6. But the code for Pagedlod read and write in the Ive plug-in was last modified in 2002/7/23. So I'm guessing it might be a problem. Cheers, Xun ------------------ Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=75350#75350