glGetString.xhtml

<div class="refentry"><a id="glGetString"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>glGetString — return a string describing the current GL connection</p></div><div class="refsynopsisdiv"><h2>C Specification</h2><div class="funcsynopsis"><table class="funcprototype-table" style="cellspacing: 0; cellpadding: 0;"><tr><td><code class="funcdef">const GLubyte* <strong class="fsfunc">glGetString</strong>(</code></td><td>GLenum <var class="pdparam">name</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div></div></div><div class="refsect1"><a id="parameters"></a><h2>Parameters</h2><div class="variablelist"><dl class="variablelist"><dt><span class="term"><em class="parameter"><code>name</code></em></span></dt><dd><p>
                    Specifies a symbolic constant, one of
                    <code class="constant">GL_VENDOR</code>, <code class="constant">GL_RENDERER</code>, <code class="constant">GL_VERSION</code>, <code class="constant">GL_SHADING_LANGUAGE_VERSION</code>, or <code class="constant">GL_EXTENSIONS</code>.
                </p></dd></dl></div></div><div class="refsect1"><a id="description"></a><h2>Description</h2><p>
            <code class="function">glGetString</code> returns a pointer to a static string
            describing some aspect of the current GL connection.
            <em class="parameter"><code>name</code></em> can be one of the following:
        </p><div class="variablelist"><dl class="variablelist"><dt><span class="term"><code class="constant">GL_VENDOR</code></span></dt><dd><p>
                        Returns the company responsible for this GL implementation.
                        This name does not change from release to release.
                    </p></dd><dt><span class="term"><code class="constant">GL_RENDERER</code></span></dt><dd><p>
                        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.
                    </p></dd><dt><span class="term"><code class="constant">GL_VERSION</code></span></dt><dd><p>
                        Returns a version or release number of the form
                        <code class="constant">OpenGL&lt;space&gt;ES&lt;space&gt;&lt;version number&gt;&lt;space&gt;&lt;vendor-specific information&gt;</code>.
                    </p></dd><dt><span class="term"><code class="constant">GL_SHADING_LANGUAGE_VERSION</code></span></dt><dd><p>
                        Returns a version or release number for the shading language of the form
                        <code class="constant">OpenGL&lt;space&gt;ES&lt;space&gt;GLSL&lt;space&gt;ES&lt;space&gt;&lt;version number&gt;&lt;space&gt;&lt;vendor-specific information&gt;</code>.
                    </p></dd><dt><span class="term"><code class="constant">GL_EXTENSIONS</code></span></dt><dd><p>
                        Returns a space-separated list of supported extensions to GL.
                    </p></dd></dl></div><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 <code class="constant">GL_VENDOR</code> and <code class="constant">GL_RENDERER</code> together uniquely specify
            a platform. They do not change from release to release and should be used
            by platform-recognition algorithms.
        </p><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 <code class="constant">GL_EXTENSIONS</code> string is a space-separated
            list of supported GL extensions.
            (Extension names never contain a space character.)
        </p><p>
            All strings are null-terminated.
        </p></div><div class="refsect1"><a id="notes"></a><h2>Notes</h2><p>
            If an error is generated, <code class="function">glGetString</code> returns 0.
        </p><p>
            The client and server may support different versions or extensions.
            <code class="function">glGetString</code> always returns a compatible version number or list of extensions.
            The release number always describes the server.
        </p></div><div class="refsect1"><a id="errors"></a><h2>Errors</h2><p>
            <code class="constant">GL_INVALID_ENUM</code> is generated if <em class="parameter"><code>name</code></em> is not an accepted value.
        </p></div><div class="refsect1"><div id="Copyright"><h2>Copyright</h2><p>
            Copyright © 1991-2006
            Silicon Graphics, Inc. This document is licensed under the SGI
            Free Software B License. For details, see
            <a class="ulink" href="http://oss.sgi.com/projects/FreeB/" target="_top">http://oss.sgi.com/projects/FreeB/</a>.
        </p></div></div></div>