upstream-man-pages/man2/xhtml/glGetString.xml

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   3 <?xml-stylesheet type="text/xsl" href="mathml.xsl"?><html xmlns="http://www.w3.org/1999/xhtml" xmlns:pref="http://www.w3.org/2002/Math/preference" pref:renderer="mathplayer-dl"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>glGetString</title><meta name="generator" content="DocBook XSL Stylesheets V1.73.2" /></head><body><div class="refentry" lang="en" xml:lang="en"><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 border="0" summary="Function synopsis" cellspacing="0" cellpadding="0"><tr><td><code class="funcdef">const GLubyte* <b class="fsfunc">glGetString</b>(</code></td><td>GLenum  </td><td><var class="pdparam">name</var><code>)</code>;</td></tr></table></div></div><div class="refsect1" lang="en" xml:lang="en"><a id="parameters"></a><h2>Parameters</h2><div class="variablelist"><dl><dt><span class="term"><em class="parameter"><code>name</code></em></span></dt><dd><p>
   4                     Specifies a symbolic constant, one of
   5                     <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>.
   6                 </p></dd></dl></div></div><div class="refsect1" lang="en" xml:lang="en"><a id="description"></a><h2>Description</h2><p>
   7             <code class="function">glGetString</code> returns a pointer to a static string
   8             describing some aspect of the current GL connection.
   9             <em class="parameter"><code>name</code></em> can be one of the following:
  10         </p><div class="variablelist"><dl><dt><span class="term"><code class="constant">GL_VENDOR</code></span></dt><dd><p>
  11                     </p><p>
  12                         Returns the company responsible for this GL implementation.
  13                         This name does not change from release to release.
  14                     </p></dd><dt><span class="term"><code class="constant">GL_RENDERER</code></span></dt><dd><p>
  15                     </p><p>
  16                         Returns the name of the renderer.
  17                         This name is typically specific to a particular configuration of a hardware
  18                         platform.
  19                         It does not change from release to release.
  20                     </p></dd><dt><span class="term"><code class="constant">GL_VERSION</code></span></dt><dd><p>
  21                     </p><p>
  22                         Returns a version or release number.
  23                     </p></dd><dt><span class="term"><code class="constant">GL_SHADING_LANGUAGE_VERSION</code></span></dt><dd><p>
  24                     </p><p>
  25                         Returns a version or release number for the shading language.
  26                     </p></dd><dt><span class="term"><code class="constant">GL_EXTENSIONS</code></span></dt><dd><p>
  27                     </p><p>
  28                         Returns a space-separated list of supported extensions to GL.
  29                     </p></dd></dl></div><p>
  30             Because the GL does not include queries for the performance
  31             characteristics of an implementation, some applications are written to
  32             recognize known platforms and modify their GL usage based on known
  33             performance characteristics of these platforms.
  34             Strings <code class="constant">GL_VENDOR</code> and <code class="constant">GL_RENDERER</code> together uniquely specify
  35             a platform. They do not change from release to release and should be used
  36             by platform-recognition algorithms.
  37         </p><p>
  38             Some applications want to make use of features that
  39             are not part of the standard GL. These features
  40             may be implemented as extensions to the standard GL.
  41             The <code class="constant">GL_EXTENSIONS</code> string is a space-separated
  42             list of supported GL extensions.
  43             (Extension names never contain a space character.)
  44         </p><p>
  45             The <code class="constant">GL_VERSION</code> and <code class="constant">GL_SHADING_LANGUAGE_VERSION</code> strings begin with a version number.
  46             The version number uses one
  47             of these forms:
  48         </p><p>
  49             <span class="emphasis"><em>major_number.minor_number</em></span>
  50             <span class="emphasis"><em>major_number.minor_number.release_number</em></span>
  51         </p><p>
  52             Vendor-specific information may follow the version
  53             number. Its format depends on the implementation, but
  54             a space always separates the version number and
  55             the vendor-specific information.
  56         </p><p>
  57             All strings are null-terminated.
  58         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="notes"></a><h2>Notes</h2><p>
  59             If an error is generated, <code class="function">glGetString</code> returns 0.
  60         </p><p>
  61             The client and server may support different versions or extensions.
  62             <code class="function">glGetString</code> always returns a compatible version number or list of extensions.
  63             The release number always describes the server.
  64         </p><p>
  65             <code class="constant">GL_SHADING_LANGUAGE_VERSION</code> is available only if the GL version is 2.0 or greater.
  66         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="errors"></a><h2>Errors</h2><p>
  67             <code class="constant">GL_INVALID_ENUM</code> is generated if <em class="parameter"><code>name</code></em> is not an accepted value.
  68         </p><p>
  69             <code class="constant">GL_INVALID_OPERATION</code> is generated if <code class="function">glGetString</code>
  70             is executed between the execution of <a class="citerefentry" href="glBegin.xml"><span class="citerefentry"><span class="refentrytitle">glBegin</span></span></a>
  71             and the corresponding execution of <a class="citerefentry" href="glEnd.xml"><span class="citerefentry"><span class="refentrytitle">glEnd</span></span></a>.
  72         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="Copyright"></a><h2>Copyright</h2><p>
  73             Copyright <span class="trademark"></span>© 1991-2006
  74             Silicon Graphics, Inc. This document is licensed under the SGI
  75             Free Software B License. For details, see
  76             <a class="ulink" href="http://oss.sgi.com/projects/FreeB/" target="_top">http://oss.sgi.com/projects/FreeB/</a>.
  77         </p></div></div></body></html>