glGetQueryObject.xhtml

<div class="refentry" lang="en" xml:lang="en"><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><tr><td><code class="funcdef">void <b class="fsfunc">glGetQueryObjectiv</b>(</code></td><td>GLuint  </td><td><var class="pdparam">id</var>, </td></tr><tr><td> </td><td>GLenum  </td><td><var class="pdparam">pname</var>, </td></tr><tr><td> </td><td>GLint *  </td><td><var class="pdparam">params</var><code>)</code>;</td></tr></table></div><div class="funcsynopsis"><table><tr><td><code class="funcdef">void <b class="fsfunc">glGetQueryObjectuiv</b>(</code></td><td>GLuint  </td><td><var class="pdparam">id</var>, </td></tr><tr><td> </td><td>GLenum  </td><td><var class="pdparam">pname</var>, </td></tr><tr><td> </td><td>GLuint *  </td><td><var class="pdparam">params</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>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>
                    Returns the requested data.
                </p></dd></dl></div></div><div class="refsect1" lang="en" xml:lang="en"><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><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_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" lang="en" xml:lang="en"><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">glGetQueryObject</code> is available only if the GL version is 1.5 or greater.
        </p></div><div class="refsect1" lang="en" xml:lang="en"><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 <code class="function">glGetQueryObject</code>
            is executed between the execution of <a class="citerefentry" href="glBegin"><span class="citerefentry"><span class="refentrytitle">glBegin</span></span></a>
            and the corresponding execution of <a class="citerefentry" href="glEnd"><span class="citerefentry"><span class="refentrytitle">glEnd</span></span></a>.
        </p></div>
        {$pipelinestall}{$examples}
        <div class="refsect1" lang="en" xml:lang="en"><a id="seealso"></a><h2>See Also</h2><p>
            <a class="citerefentry" href="glBeginQuery"><span class="citerefentry"><span class="refentrytitle">glBeginQuery</span></span></a>,
            <a class="citerefentry" href="glEndQuery"><span class="citerefentry"><span class="refentrytitle">glEndQuery</span></span></a>,
            <a class="citerefentry" href="glGetQueryiv"><span class="citerefentry"><span class="refentrytitle">glGetQueryiv</span></span></a>,
            <a class="citerefentry" href="glIsQuery"><span class="citerefentry"><span class="refentrytitle">glIsQuery</span></span></a>
        </p></div><div class="refsect1" lang="en" xml:lang="en"><div id="Copyright"><h2>Copyright</h2><p>
            Copyright © 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="https://opencontent.org/openpub/" target="_top">https://opencontent.org/openpub/</a>.
        </p></div></div></div>