GLAPI/glGetString

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glGetString
Core in version 4.5
Core since version 1.0

glGetString: return a string describing the current GL connection

Function Definition

 const GLubyte* glGetString(GLenum name​);
 const GLubyte* glGetStringi(GLenum name​, GLuint index​);
name
Specifies a symbolic constant, one of GL_VENDOR, GL_RENDERER, GL_VERSION, or GL_SHADING_LANGUAGE_VERSION. Additionally, glGetStringi accepts the GL_EXTENSIONS token.
index
For glGetStringi, specifies the index of the string to return.

Description

glGetString returns a pointer to a static string describing some aspect of the current GL connection. name​ can be one of the following:

GL_VENDOR

Returns the company responsible for this GL implementation. This name does not change from release to release.

GL_RENDERER

Returns the name of the renderer. This name is typically specific to a particular configuration of a hardware platform. It does not change from release to release.

GL_VERSION

Returns a version or release number.

GL_SHADING_LANGUAGE_VERSION

Returns a version or release number for the shading language.

Strings GL_VENDOR and GL_RENDERER together uniquely specify a platform. They do not change from release to release and should be used by platform-recognition algorithms.

The GL_VERSION and GL_SHADING_LANGUAGE_VERSION strings retrieved from glGetString begin with a version number. The version number uses one of these forms:

 major_number​.minor_number​

or

 major_number​.minor_number​.release_number​

Vendor-specific information may follow the version number. Its format depends on the implementation, but a space always separates the version number and the vendor-specific information.

glGetStringi returns a pointer to a static string indexed by index​. name​ can be one of the following:

GL_EXTENSIONS
For glGetStringi only, returns the extension string supported by the implementation at index​. The index index​ is on the range [0 to glGetIntegerv(GL_NUM_EXTENSIONS) - 1].
GL_SHADING_LANGUAGE_VERSION
Returns one of the versions of GLSL supported by this implementation. index​ is on the range [0 to glGetIntegerv(GL_NUM_SHADING_LANGUAGE_VERSIONS) - 1].

The GL_SHADING_LANGUAGE_VERSION strings retrieved using glGetStringi use the formatting of GLSL's #version​ declaration. This has the following forms:

 number​

or

 number​ profile​

The profile​ is only present for versions of GLSL that have this distinction.

Note that GLSL only gained the #version​ declaration in version 1.10; if an implementation exposes support for GLSL 1.00 (through ARB_shading_language_100), then it will return an empty string ("").

Versions of the GLSL for OpenGL ES can also be supported. If an implementation returns "100", this does not refer to GLSL 1.00. It instead refers to support for OpenGL ES's 2.0's GLSL ES version 1.00. The profile​ can also be "es", which represents a version of OpenGL ES's shading language. So version "300 es" represents GLSL ES 3.00. GLSL ES 1.00 does not use the "es" profile name.

All strings returned by these functions are null-terminated.

Notes

If an error is generated, the functions return 0.

The client and server may support different versions. glGetString always returns a compatible version number. The release number always describes the server.

Errors

GL_INVALID_ENUM is generated if name​ is not an accepted value.

GL_INVALID_VALUE is generated by glGetStringi if index​ is outside the valid range for indexed state name​.

Copyright

Copyright © 1991-2006 Silicon Graphics, Inc. Copyright © 2010 Khronos Group. This document is licensed under the SGI Free Software B License. For details, see http://oss.sgi.com/projects/FreeB/.