OpenSceneGraph is an open-source 3D graphics application programming interface (library or framework), used by application developers in fields such as visual simulation, computer games, virtual reality, scientific visualization and modeling. The toolkit is written in standard C++ using OpenGL, and runs on a variety of operating systems including Microsoft Windows, macOS, Linux, IRIX, Solaris and FreeBSD. Since version 3.0.0, OpenSceneGraph also supports application development for mobile platforms, namely iOS and Android. As of 2021, the project is being succeeded by VulkanSceneGraph project, a Vulkan-based library. OpenSceneGraph is in maintenance phase since 2019. History The OpenSceneGraph project was initiated by Don Burns in 1998. Robert Osfield joined the project during 1999, working on porting finished components for Microsoft Windows. The project went open source in September 1999 and the official project website was created. Towards the end of the year Osfield took over the project and began extensive refactoring of the existing codebase, putting emphasis on modernisation, embracing modern C++ standards and design patterns. In April 2001, taking into account growing community of users and interest of public, Robert Osfield created OpenSceneGraph Professional Services, providing commercial support, consulting and training services. This marks full professionalization of the project. The first official stable version of OpenSceneGraph was version 1.0, released in 2005. An extended version 2.0 followed in 2007, adding support for multi-core and multi-gpu systems, several important NodeKits and usage of unified multiplatform build system CMake. Books and user handbooks were introduced. The project has been quickly growing and becoming more popular ever since. There are more than 530 contributors signed under current stable version, and the official mailing list contains thousands of names. In 2019, the project was moved to a maintenance phase, the main development effort being routed to its successor project VulkanSceneGraph. Features Features in version 1.0: A feature-rich and widely adopted scene graph implementation Support for performance increasing features View frustum, small feature and occlusion culling Level of detail State sorting and lazy state updating OpenGL fast paths and latest extensions Multi-threading and database optimization Support for OpenGL, from 1.1 through 2.0 including the latest extensions Tightly coupled support for OpenGL Shading Language, developed in conjunction with 3Dlabs Support for a wide range of 2D image and 3D database formats, with loaders available for formats such as OpenFlight, TerraPage, OBJ, 3DS, JPEG, PNG and GeoTIFF Particle effects Support for anti-aliased TrueType text Seamless support for framebuffer objects,