SoPolygonOffset(3) on Linux
The text 7cd06aae8c3d, as Debian 4.0 (Etch) shipped it.
The SoPolygonOffset class is a node type for 'layering' rendering primitives. A common problem with realtime 3D rendering systems is that rendered primitives which are at approximately the same depth with regard to the camera viewpoint will appear to flicker. I.e.: from one angle one primitive will appear to be closer, while at another angle, another primitive will appear closer. When this happens, the rendered graphics at that part of the scene will of course look a lot less visually pleasing.