1 <?xml version=
"1.0" encoding=
"UTF-8"?>
2 <!DOCTYPE html PUBLIC
"-//W3C//DTD XHTML 1.0 Transitional//EN" "xhtml1-transitional.dtd">
3 <!-- saved from url=(0013)about:internet -->
4 <?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" /><link rel=
"stylesheet" type=
"text/css" href=
"opengl-man.css" /><title>glGetActiveUniformBlockName - OpenGL
4 Reference Pages
</title><meta name=
"generator" content=
"DocBook XSL Stylesheets V1.69.1" /></head><body><div class=
"refentry" lang=
"en" xml:
lang=
"en"><a id=
"glGetActiveUniformBlockName"></a><div class=
"titlepage"></div><div class=
"refnamediv"><h2>Name
</h2><p>glGetActiveUniformBlockName — retrieve the name of an active uniform block
</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">void
<b class=
"fsfunc">glGetActiveUniformBlockName
</b>(
</code></td><td>GLuint
</td><td><var class=
"pdparam">program
</var>,
</td></tr><tr><td> </td><td>GLuint
</td><td><var class=
"pdparam">uniformBlockIndex
</var>,
</td></tr><tr><td> </td><td>GLsizei
</td><td><var class=
"pdparam">bufSize
</var>,
</td></tr><tr><td> </td><td>GLsizei *
</td><td><var class=
"pdparam">length
</var>,
</td></tr><tr><td> </td><td>GLchar *
</td><td><var class=
"pdparam">uniformBlockName
</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>program
</code></em></span></dt><dd><p>
5 Specifies the name of a program containing the uniform block.
6 </p></dd><dt><span class=
"term"><em class=
"parameter"><code>uniformBlockIndex
</code></em></span></dt><dd><p>
7 Specifies the index of the uniform block within
<em class=
"parameter"><code>program
</code></em>.
8 </p></dd><dt><span class=
"term"><em class=
"parameter"><code>bufSize
</code></em></span></dt><dd><p>
9 Specifies the size of the buffer addressed by
<em class=
"parameter"><code>uniformBlockName
</code></em>.
10 </p></dd><dt><span class=
"term"><em class=
"parameter"><code>length
</code></em></span></dt><dd><p>
11 Specifies the address of a variable to receive the number of characters that were written to
<em class=
"parameter"><code>uniformBlockName
</code></em>.
12 </p></dd><dt><span class=
"term"><em class=
"parameter"><code>uniformBlockName
</code></em></span></dt><dd><p>
13 Specifies the address an array of characters to receive the name of the uniform block at
<em class=
"parameter"><code>uniformBlockIndex
</code></em>.
14 </p></dd></dl></div></div><div class=
"refsect1" lang=
"en" xml:
lang=
"en"><a id=
"description"></a><h2>Description
</h2><p>
15 <code class=
"function">glGetActiveUniformBlockName
</code> retrieves the name of the active uniform block at
<em class=
"parameter"><code>uniformBlockIndex
</code></em>
16 within
<em class=
"parameter"><code>program
</code></em>.
18 <em class=
"parameter"><code>program
</code></em> must be the name of a program object for which the command
19 <a href=
"glLinkProgram.xml"><span class=
"citerefentry"><span class=
"refentrytitle">glLinkProgram
</span></span></a> must have been called in the past, although it is not required that
20 <a href=
"glLinkProgram.xml"><span class=
"citerefentry"><span class=
"refentrytitle">glLinkProgram
</span></span></a> must have succeeded. The link could have failed because the number
21 of active uniforms exceeded the limit.
23 <em class=
"parameter"><code>uniformBlockIndex
</code></em> is an active uniform block index of
<em class=
"parameter"><code>program
</code></em>, and must be less than the value
24 of
<code class=
"constant">GL_ACTIVE_UNIFORM_BLOCKS
</code>.
26 Upon success, the name of the uniform block identified by
<em class=
"parameter"><code>unifomBlockIndex
</code></em> is returned into
27 <em class=
"parameter"><code>uniformBlockName
</code></em>. The name is nul-terminated. The actual number of characters written into
<em class=
"parameter"><code>uniformBlockName
</code></em>,
28 excluding the nul terminator, is returned in
<em class=
"parameter"><code>length
</code></em>. If
<em class=
"parameter"><code>length
</code></em> is
<code class=
"code">NULL
</code>, no length is returned.
30 <em class=
"parameter"><code>bufSize
</code></em> contains the maximum number of characters (including the nul terminator) that will be written into
31 <em class=
"parameter"><code>uniformBlockName
</code></em>.
33 If an error occurs, nothing will be written to
<em class=
"parameter"><code>uniformBlockName
</code></em> or
<em class=
"parameter"><code>length
</code></em>.
34 </p></div><div class=
"refsect1" lang=
"en" xml:
lang=
"en"><a id=
"errors"></a><h2>Errors
</h2><p>
35 <code class=
"constant">GL_INVALID_OPERATION
</code> is generated if
<em class=
"parameter"><code>program
</code></em> is not the name of a program object for which
36 <a href=
"glLinkProgram.xml"><span class=
"citerefentry"><span class=
"refentrytitle">glLinkProgram
</span></span></a> has been called in the past.
38 <code class=
"constant">GL_INVALID_VALUE
</code> is generated if
<em class=
"parameter"><code>uniformBlockIndex
</code></em> is greater than or equal to the value
39 of
<code class=
"constant">GL_ACTIVE_UNIFORM_BLOCKS
</code> or is not the index of an active uniform block in
<em class=
"parameter"><code>program
</code></em>.
40 </p></div><div class=
"refsect1" lang=
"en" xml:
lang=
"en"><a id=
"notes"></a><h2>Notes
</h2><p>
41 <code class=
"function">glGetActiveUniformBlockName
</code> is available only if the GL version is
3.1 or greater.
42 </p></div><div class=
"refsect1" lang=
"en" xml:
lang=
"en"><a id=
"seealso"></a><h2>See Also
</h2><p>
43 <a href=
"glGetActiveUniformBlock.xml"><span class=
"citerefentry"><span class=
"refentrytitle">glGetActiveUniformBlock
</span></span></a>,
44 <a href=
"glGetUniformBlockIndex.xml"><span class=
"citerefentry"><span class=
"refentrytitle">glGetUniformBlockIndex
</span></span></a>
45 </p></div><div class=
"refsect1" lang=
"en" xml:
lang=
"en"><a id=
"Copyright"></a><h2>Copyright
</h2><p>
46 Copyright
<span class=
"trademark"></span>©
2010 Khronos Group.
47 This material may be distributed subject to the terms and conditions set forth in
48 the Open Publication License, v
1.0,
8 June
1999.
49 <a href=
"http://opencontent.org/openpub/" target=
"_top">http://opencontent.org/openpub/
</a>.
50 </p></div></div></body></html>