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<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "xhtml1-transitional.dtd">
<?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>glGetQueryObject - OpenGL 4 Reference Pages</title><meta name="generator" content="DocBook XSL Stylesheets V1.78.1" /></head><body><div class="refentry"><a id="glGetQueryObject"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>glGetQueryObject — return parameters of a query object</p></div><div class="refsynopsisdiv"><h2>C Specification</h2><div class="funcsynopsis"><table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"><tr><td><code class="funcdef">void <strong class="fsfunc">glGetQueryObjectiv</strong>(</code></td><td>GLuint <var class="pdparam">id</var>, </td></tr><tr><td> </td><td>GLenum <var class="pdparam">pname</var>, </td></tr><tr><td> </td><td>GLint * <var class="pdparam">params</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div></div><div class="funcsynopsis"><table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"><tr><td><code class="funcdef">void <strong class="fsfunc">glGetQueryObjectuiv</strong>(</code></td><td>GLuint <var class="pdparam">id</var>, </td></tr><tr><td> </td><td>GLenum <var class="pdparam">pname</var>, </td></tr><tr><td> </td><td>GLuint * <var class="pdparam">params</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div></div><div class="funcsynopsis"><table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"><tr><td><code class="funcdef">void <strong class="fsfunc">glGetQueryObjecti64v</strong>(</code></td><td>GLuint <var class="pdparam">id</var>, </td></tr><tr><td> </td><td>GLenum <var class="pdparam">pname</var>, </td></tr><tr><td> </td><td>GLint64 * <var class="pdparam">params</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div></div><div class="funcsynopsis"><table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"><tr><td><code class="funcdef">void <strong class="fsfunc">glGetQueryObjectui64v</strong>(</code></td><td>GLuint <var class="pdparam">id</var>, </td></tr><tr><td> </td><td>GLenum <var class="pdparam">pname</var>, </td></tr><tr><td> </td><td>GLuint64 * <var class="pdparam">params</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>id</code></em></span></dt><dd><p>
Specifies the name of a query object.
</p></dd><dt><span class="term"><em class="parameter"><code>pname</code></em></span></dt><dd><p>
Specifies the symbolic name of a query object parameter.
Accepted values are <code class="constant">GL_QUERY_RESULT</code> or <code class="constant">GL_QUERY_RESULT_AVAILABLE</code>.
</p></dd><dt><span class="term"><em class="parameter"><code>params</code></em></span></dt><dd><p>
If a buffer is bound to the <code class="constant">GL_QUERY_RESULT_BUFFER</code> target, then <em class="parameter"><code>params</code></em>
is treated as an offset to a location within that buffer's data store to receive the result of the query. If
no buffer is bound to <code class="constant">GL_QUERY_RESULT_BUFFER</code>, then <em class="parameter"><code>params</code></em> is
treated as an address in client memory of a variable to receive the resulting data.
</p></dd></dl></div></div><div class="refsect1"><a id="description"></a><h2>Description</h2><p>
<code class="function">glGetQueryObject</code> returns in <em class="parameter"><code>params</code></em> a selected parameter of the query object
specified by <em class="parameter"><code>id</code></em>.
</p><p>
<em class="parameter"><code>pname</code></em> names a specific query object parameter. <em class="parameter"><code>pname</code></em> can be as follows:
</p><div class="variablelist"><dl class="variablelist"><dt><span class="term"><code class="constant">GL_QUERY_RESULT</code></span></dt><dd><p>
<em class="parameter"><code>params</code></em> returns the value of the query object's passed samples counter.
The initial value is 0.
</p></dd><dt><span class="term"><code class="constant">GL_QUERY_RESULT_NO_WAIT</code></span></dt><dd><p>
If the result of the query is available (that is, a query of <code class="constant">GL_QUERY_RESULT_AVAILABLE</code> would
return non-zero), then <em class="parameter"><code>params</code></em> returns the value of the query object's passed samples counter,
otherwise, the data referred to by <em class="parameter"><code>params</code></em> is not modified.
The initial value is 0.
</p></dd><dt><span class="term"><code class="constant">GL_QUERY_RESULT_AVAILABLE</code></span></dt><dd><p>
<em class="parameter"><code>params</code></em> returns whether the passed samples counter is immediately available.
If a delay would occur waiting for the query result, <code class="constant">GL_FALSE</code> is returned.
Otherwise, <code class="constant">GL_TRUE</code> is returned, which also indicates that the results of all
previous queries are available as well.
</p></dd></dl></div></div><div class="refsect1"><a id="notes"></a><h2>Notes</h2><p>
If an error is generated,
no change is made to the contents of <em class="parameter"><code>params</code></em>.
</p><p>
<code class="function">glGetQueryObject</code> implicitly flushes the GL pipeline so that any incomplete rendering
delimited by the occlusion query completes in finite time.
</p><p>
If multiple queries are issued using the same query object <em class="parameter"><code>id</code></em> before calling
<code class="function">glGetQueryObject</code>, the results of the most recent query will be returned. In this case,
when issuing a new query, the results of the previous query are discarded.
</p><p>
<code class="function">glGetQueryObjecti64v</code> and <code class="function">glGetQueryObjectui64v</code> are available only
if the GL version is 3.3 or greater.
</p><p>
<code class="constant">GL_QUERY_RESULT_NO_WAIT</code> is accepted for <em class="parameter"><code>pname</code></em> only if the
GL version is 4.4 or greater.
</p><p>
The <code class="constant">GL_QUERY_RESULT_BUFFER</code> target is available only if the GL version is 4.4 or higher.
On earlier versions of the GL, <em class="parameter"><code>params</code></em> is always an address in client memory.
</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>pname</code></em> is not an accepted value.
</p><p>
<code class="constant">GL_INVALID_OPERATION</code> is generated if <em class="parameter"><code>id</code></em> is not the name of a query object.
</p><p>
<code class="constant">GL_INVALID_OPERATION</code> is generated if <em class="parameter"><code>id</code></em> is the name of a currently active
query object.
</p><p>
<code class="constant">GL_INVALID_OPERATION</code> is generated if a buffer is currently bound to the
<code class="constant">GL_QUERY_RESULT_BUFFER</code> target and the command would cause data to be written beyond the bounds
of that buffer's data store.
</p></div><div class="refsect1"><a id="seealso"></a><h2>See Also</h2><p>
<a class="citerefentry" href="glBeginQuery.xml"><span class="citerefentry"><span class="refentrytitle">glBeginQuery</span></span></a>,
<a class="citerefentry" href="glEndQuery.xml"><span class="citerefentry"><span class="refentrytitle">glEndQuery</span></span></a>,
<a class="citerefentry" href="glGetQueryiv.xml"><span class="citerefentry"><span class="refentrytitle">glGetQueryiv</span></span></a>,
<a class="citerefentry" href="glIsQuery.xml"><span class="citerefentry"><span class="refentrytitle">glIsQuery</span></span></a>,
<a class="citerefentry" href="glQueryCounter.xml"><span class="citerefentry"><span class="refentrytitle">glQueryCounter</span></span></a>
</p></div><div class="refsect1"><a id="Copyright"></a><h2>Copyright</h2><p>
Copyright <span class="trademark"></span>© 2005 Addison-Wesley.
Copyright <span class="trademark"></span>© 2010-2013 Khronos Group.
This material may be distributed subject to the terms and conditions set forth in
the Open Publication License, v 1.0, 8 June 1999.
<a class="ulink" href="http://opencontent.org/openpub/" target="_top">http://opencontent.org/openpub/</a>.
</p></div></div></body></html>
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