OpenSceneGraph - 3D graphics toolkit
The OpenSceneGraph is an open source high performance 3D graphics toolkit, used by application developers in fields such as visual simulation, games, virtual reality, scientific visualization and modelling. It is based around the concept of a SceneGraph, providing an object-oriented framework on top of OpenGL. This frees the developer from implementing and optimizing low-level graphics calls and provides many additional utilities for rapid development of graphics applications.
It supports view-frustum culling, occlusion culling, small feature culling, Level Of Detail (LOD) nodes, OpenGL state sorting, vertex arrays, vertex buffer objects, OpenGL Shader Language and display lists as part of the core scene graph. These together make the OpenSceneGraph one of the highest performance graphics toolkit available. The OpenSceneGraph also supports easy customization of the drawing process, such as implementation of Continuous Level of Detail (CLOD) meshes on top of the scene graph (see Virtual Terrain Project and Delta3D).