Hi Fred, You shouldn't need to do anything to handle dataset with large values, the OSG and VPB are built to manage things for you. When VPB builds databases it decorates subgraphs with local transforms that place the subgraphs into world coordinates, whilst the subgraph containing the geometry have a local origin. By default the OSG uses doubles for Transforms in the scene graph and doubles in the Camera matrices, and the cull traversal accumulates these all in doubles before finally passing a single modelview matrix to OpenGL. This approach ensures that you be the best possible precision when rendering whole earth datasets.
So the answer is, stop trying so hard, everything is being done for you already ;-) Robert. On 3 September 2013 14:16, Fred Dorosh <[email protected]> wrote: > Hi, > > I am generating terrain patches which will eventually be parented in the > scenegraph to transforms relative to a predefined runtime scene origin. > > When using OSGDem to generate terrain tiles from UTM-georeferenced data, > my geometry receives very large coordinates, which I would like to > reposition relative to a specific UTM origin. > > That's my goal - a hamfisted solution would be to translate everything by > (-origin), including the PagedLOD Center, RangeLists, TerrainTiles and > Heightfield Origin. There seems to be no built-in option to support this, > although I imagine it's a common use case. > > Am I missing something obvious? > > Thank you! > > Cheers, > Fred > > ------------------ > Read this topic online here: > http://forum.openscenegraph.org/viewtopic.php?p=56086#56086 > > > > > > _______________________________________________ > osg-users mailing list > [email protected] > http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org >
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