These extensions are multi-vendor as well, but they are specifically approved by the OpenGL ARB. There is a higher level of EXT extensions, called GL_ARB. It is also a signal to the user of OpenGL that this extension may find its way into other implementations. This does not ensure that they are implemented by all IHVs, but it means that the extension is available to be implemented by multiple vendors. They can be implemented by any implementation. The name of each extension starts with a prefix, specifying what type it is.Įxtensions that start with GL_EXT are generic extensions. There are many automatic tools for loading them.Įxtensions fall into 3 broad categories: vendor-specific, generic, and ARB-approved. OpenGL extensions must be loaded dynamically at runtime.
For more information, see Get Context Info. It is possible to check at run-time whether an extension is supported or not. That version is often (but not always) the minimum version that the extension can be used together with. specifies a modification to that core version's spec. The exception to this is core extensions, which is explained below.Īll extensions are written against a version of OpenGL. For example, the extension GL_ARB_multitexture (which has been adapted into the core) contains the function glActiveTextureARB and the token GL_TEXTURE0_ARB. The name of the tokens and functions ends with the prefix of the extension. If an extension is supported on a specific computer, it means those tokens and/or functions can be used there. Quite a few of these extensions have been folded into the OpenGL core.Īn extension always contains at least one enum token, or one function. Many of these extensions are old and obsolete in modern programming practice they are listed for the sake of completeness. The extension registry has over 300 extensions listed. The registry also contains guidelines for creating new extensions and has example C/C++ header files containing function entry points and token enums. The OpenGL Extension Registry is maintained by the ARB and contains the technical specifications of all known OpenGL extensions.
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