Editing OpenGL (section)

==Associated libraries==
The earliest versions of OpenGL were released with a companion library called the [[OpenGL Utility Library]] (GLU). It provided simple, useful features which were unlikely to be supported in contemporary hardware, such as [[Tessellation (computer graphics)|tessellating]], and generating [[mipmap]]s and [[geometric primitive|primitive shapes]]. The GLU specification was last updated in 1998 and depends on OpenGL features which are now [[deprecation|deprecated]].

===Context and window toolkits===
Given that creating an OpenGL context is quite a complex process, and given that it varies between [[operating system]]s, automatic OpenGL context creation has become a common feature of several game-development and user-interface [[library (computing)|libraries]], including [[Simple DirectMedia Layer|SDL]], [[Allegro (software)|Allegro]], [[Simple and Fast Multimedia Library|SFML]], [[FLTK]], and [[Qt (software)|Qt]]. A few libraries have been designed solely to produce an OpenGL-capable window. The first such library was [[OpenGL Utility Toolkit]] (GLUT), later superseded by [[freeglut]]. [[GLFW]] is a newer alternative.<ref>{{cite web|url=https://www.opengl.org/resources/libraries/windowtoolkits/ |title=A list of GLUT alternatives, maintained by |publisher=Khronos Group |access-date=May 2, 2013}}</ref>
* These toolkits are designed to create and manage OpenGL windows, and manage input, but little beyond that.<ref>{{cite web|title=Related toolkits and APIs|url=https://www.opengl.org/wiki/Related_toolkits_and_APIs#Context.2FWindow_Toolkits|website=www.opengl.org|publisher=OpenGL|access-date=October 8, 2014}}</ref>
:* [[GLFW]] – A cross-platform windowing and keyboard-mouse-joystick handler; is more game-oriented
:* [[freeglut]] – A cross-platform windowing and keyboard-mouse handler; its API is a superset of the GLUT API, and it is more stable and up to date than GLUT
:* [[OpenGL Utility Toolkit]] (GLUT) – An old windowing handler, no longer maintained.
* Several "multimedia libraries" can create OpenGL windows, in addition to input, sound and other tasks useful for game-like applications
:* [[Allegro (software)|Allegro 5]] – A cross-platform multimedia library with a C API focused on game development
:* [[Simple DirectMedia Layer]] (SDL) – A cross-platform multimedia library with a C API
:* [[Simple and Fast Multimedia Library|SFML]] – A cross-platform multimedia library with a C++ API and multiple other bindings to languages such as C#, Java, Haskell, and Go
* Widget toolkits
:* [[FLTK]] – A small cross-platform C++ widget library
:* [[Qt (software)|Qt]] – A cross-platform C++ widget toolkit. It provides many OpenGL helper objects, which even abstract away the difference between desktop GL and OpenGL ES
:* [[wxWidgets]] – A cross-platform C++ widget toolkit

===Extension loading libraries===
Given the high workload involved in identifying and loading OpenGL extensions, a few libraries have been designed which load all available extensions and functions automatically. Examples include OpenGL Easy Extension library (GLEE), OpenGL Extension Wrangler Library (GLEW) and [[glbinding]]. Extensions are also loaded automatically by most language bindings, such as [[Java OpenGL]], PyOpenGL and [[WebGL]].

===Implementations===
[[File:Glxinfo with glxgears screenshot.png|thumb|Screenshot of <code>glxinfo</code>, showing information of Mesa implementation of OpenGL on a system and <code>glxgears</code>, a program to test OpenGL implementation on a system]]
[[Mesa (computer graphics)|Mesa 3D]] is an [[Open-source software|open-source]] implementation of OpenGL. It can do pure software rendering, and it may also use hardware acceleration on [[Berkeley Software Distribution|BSD]], [[Linux]], and other platforms by taking advantage of the [[Direct Rendering Infrastructure]]. As of version 20.0, it implements version 4.6 of the OpenGL standard.