SbSphereSheetProjector(3) on Linux
The text f48a8ae6c08d, as Debian 7 (Wheezy) shipped it.
The SbSphereSheetProjector class projects 2D points to 3D points on a sheet covering a spherical shape. The following stand-alone example shows how screen space coordinates projects into 3D when mapped with an SbSphereSheetProjector. It outputs the resulting projections as an SoPointSet in a Inventor-file on stdout: