The OpenSceneGraph is an open source cross platform graphics toolkit for the development of high performance graphics applications such as flight simulators, games, virtual reality and scientific visualization. Based around the concept of a scene graph, it provides an object oriented framework on top of OpenGL freeing the developer from implementing and optimizing low level graphics calls, and provides many additional utilities for rapid development of graphics applications. gdal, gtkglext and OpenAL are optional dependencies. Also ffmpeg would be one, but support here it's broken ATM.