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<?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>glGetQueryiv</title><meta name="generator" content="DocBook XSL Stylesheets V1.78.1" /></head><body><div class="refentry"><a id="glGetQueryiv"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>glGetQueryiv — return parameters of a query object target</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">glGetQueryiv</strong>(</code></td><td>GLenum <var class="pdparam">target</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><div class="refsect1"><a id="parameters"></a><h2>Parameters</h2><div class="variablelist"><dl class="variablelist"><dt><span class="term"><em class="parameter"><code>target</code></em></span></dt><dd><p>
                    Specifies a query object target.
                    Must be <code class="constant">GL_SAMPLES_PASSED</code>.
                </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 target parameter.
                    Accepted values are <code class="constant">GL_CURRENT_QUERY</code> or <code class="constant">GL_QUERY_COUNTER_BITS</code>.
                </p></dd><dt><span class="term"><em class="parameter"><code>params</code></em></span></dt><dd><p>
                    Returns the requested data.
                </p></dd></dl></div></div><div class="refsect1"><a id="description"></a><h2>Description</h2><p>
            <code class="function">glGetQueryiv</code> returns in <em class="parameter"><code>params</code></em> a selected parameter of the query object target
            specified by <em class="parameter"><code>target</code></em>.
        </p><p>
            <em class="parameter"><code>pname</code></em> names a specific query object target parameter.  When <em class="parameter"><code>target</code></em> is 
            <code class="constant">GL_SAMPLES_PASSED</code>, <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_CURRENT_QUERY</code></span></dt><dd><p>
                        <em class="parameter"><code>params</code></em> returns the name of the currently active occlusion query object.
                        If no occlusion query is active, 0 is returned.  The initial value is 0.
                    </p></dd><dt><span class="term"><code class="constant">GL_QUERY_COUNTER_BITS</code></span></dt><dd><p>
                        <em class="parameter"><code>params</code></em> returns the number of bits in the query counter used to accumulate passing samples.
                        If the number of bits returned is 0, the implementation does not support a query counter, and the results 
                        obtained from <a class="citerefentry" href="glGetQueryObject.xml"><span class="citerefentry"><span class="refentrytitle">glGetQueryObject</span></span></a> are useless.
                    </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">glGetQueryiv</code> is available only if the GL version is 1.5 or greater.
        </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>target</code></em> or <em class="parameter"><code>pname</code></em> is not an
            accepted value.
        </p><p>
            <code class="constant">GL_INVALID_OPERATION</code> is generated if <code class="function">glGetQueryiv</code>
            is executed between the execution of <a class="citerefentry" href="glBegin.xml"><span class="citerefentry"><span class="refentrytitle">glBegin</span></span></a>
            and the corresponding execution of <a class="citerefentry" href="glEnd.xml"><span class="citerefentry"><span class="refentrytitle">glEnd</span></span></a>.
        </p></div><div class="refsect1"><a id="seealso"></a><h2>See Also</h2><p>
            <a class="citerefentry" href="glGetQueryObject.xml"><span class="citerefentry"><span class="refentrytitle">glGetQueryObject</span></span></a>,
            <a class="citerefentry" href="glIsQuery.xml"><span class="citerefentry"><span class="refentrytitle">glIsQuery</span></span></a>
        </p></div><div class="refsect1"><a id="Copyright"></a><h2>Copyright</h2><p>
            Copyright <span class="trademark"></span>© 2005 Addison-Wesley. 
            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>