xenocara/doc/gl-docs/GL/gl/getstring.3gl

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'\" e
'\"! eqn | mmdoc
'\"macro stdmacro
.ds Vn Version 1.2
.ds Dt 24 September 1999
.ds Re Release 1.2.1
.ds Dp Jan 14 18:30
.ds Dm 01 getstring
.ds Xs 56397 5 getstring.gl
.TH GLGETSTRING 3G
.SH NAME
.B "glGetString
\- return a string describing the current GL connection
.SH C SPECIFICATION
const GLubyte* \f3glGetString\fP(
GLenum \fIname\fP )
.SH PARAMETERS
.TP \w'\fIname\fP\ \ 'u
\f2name\fP
Specifies a symbolic constant, one of
\%\f3GL_VENDOR\fP, \%\f3GL_RENDERER\fP, \%\f3GL_VERSION\fP, or \%\f3GL_EXTENSIONS\fP.
.SH DESCRIPTION
\%\f3glGetString\fP returns a pointer to a static string
describing some aspect of the current GL connection.
\f2name\fP can be one of the following:
.TP 20
\%\f3GL_VENDOR\fP
Returns the company responsible for this GL implementation.
This name does not change from release to release.
.TP
\%\f3GL_RENDERER\fP
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.
.TP
\%\f3GL_VERSION\fP
Returns a version or release number.
.TP
\%\f3GL_EXTENSIONS\fP
Returns a space-separated list of supported extensions to GL.
.P
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 \%\f3GL_VENDOR\fP and \%\f3GL_RENDERER\fP together uniquely specify
a platform. They do not change from release to release and should be used
by platform-recognition algorithms.
.P
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 \%\f3GL_EXTENSIONS\fP string is a space-separated
list of supported GL extensions.
(Extension names never contain a space character.)
.P
The \%\f3GL_VERSION\fP string begins with a version number.
The version number uses one
of these forms:
.P
\f2major_number.minor_number\fP
.br
\f2major_number.minor_number.release_number\fP
.P
Vendor-specific information may follow the version
number. Its depends on the implementation, but
a space always separates the version number and
the vendor-specific information.
.P
All strings are null-terminated.
.SH NOTES
If an error is generated, \%\f3glGetString\fP returns 0.
.P
The client and server may support different versions or extensions.
\%\f3glGetString\fP always returns a compatible version number or list of extensions.
The release number always describes the server.
.SH ERRORS
\%\f3GL_INVALID_ENUM\fP is generated if \f2name\fP is not an accepted value.
.P
\%\f3GL_INVALID_OPERATION\fP is generated if \%\f3glGetString\fP
is executed between the execution of \%\f3glBegin\fP
and the corresponding execution of \%\f3glEnd\fP.