GLUI is a GLUT-based C++ user interface library which provides controls such as buttons, checkboxes, radio buttons, and spinners to OpenGL applications. It is window-system independent, using GLUT or FreeGLUT.
Designed for non-expert scientists considering to use VR, Aura presents an easy-to-understand C++ API that extends basic available low-level graphics facilities like OpenGL or Direct3D with scene graph management paradigms and a VR programming framework.
Clawlib is or intends to be a cross platform C++ library
Ivf++ is a small class library encapsulating OpenGL functionality. It comes with ~10 tutorials and a user's guide. See homepage for latest news and updates.
Terrain Voyager Engine is an OpenGL accelerated, multi-platform (Win32, Linux, IRIX) landscape engine. One of the goal of it is to make a small FPS game.
The VR Juggler Toolbox is a collection of libraries and tools for use with VR Juggler applications.
osgJuggler is a library suite that makes developing computer graphics appications for virtual reality easier. osgJuggler is a framework that allows you to develop a scene with OpenSceneGraph and view it on any platform supported by VRJuggler.