glGetString — return a string describing the current GL connection
const GLubyte* glGetString( | GLenum | name) ; |
name
Specifies a symbolic constant, one of
GL_VENDOR
, GL_RENDERER
, GL_VERSION
, GL_SHADING_LANGUAGE_VERSION
, or GL_EXTENSIONS
.
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.
GL_EXTENSIONS
Returns a space-separated list of supported extensions to GL.
Because the GL does not include queries for the performance
characteristics of an implementation, some applications are written to
recognize known platforms and modify their GL usage based on known
performance characteristics of these platforms.
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.
Some applications want to make use of features that
are not part of the standard GL. These features
may be implemented as extensions to the standard GL.
The GL_EXTENSIONS
string is a space-separated
list of supported GL extensions.
(Extension names never contain a space character.)
The GL_VERSION
and GL_SHADING_LANGUAGE_VERSION
strings begin with a version number.
The version number uses one
of these forms:
major_number.minor_number 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.
All strings are null-terminated.
If an error is generated, glGetString
returns 0.
The client and server may support different versions or extensions.
glGetString
always returns a compatible version number or list of extensions.
The release number always describes the server.
GL_SHADING_LANGUAGE_VERSION
is available only if the GL version is 2.0 or greater.
GL_INVALID_ENUM
is generated if name
is not an accepted value.
GL_INVALID_OPERATION
is generated if glGetString
is executed between the execution of glBegin
and the corresponding execution of glEnd.
Copyright © 1991-2006 Silicon Graphics, Inc. This document is licensed under the SGI Free Software B License. For details, see http://oss.sgi.com/projects/FreeB/.