SoVRMLProximitySensor(3) on Linux
The text d6a7e9da4ab0, as Debian 6.0 (Squeeze) shipped it.
The SoVRMLProximitySensor class is used to generate events when the viewer enters or exits a region. The detailed class documentation is taken verbatim from the VRML97 standard (ISO/IEC 14772-1:1997). It is copyright The Web3D Consortium, and is used by permission of the Consortium:.