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<refentry id="glGetMultisample">
    <refentryinfo>
        <copyright>
            <year>2010-2013</year>
            <holder>Khronos Group</holder>
        </copyright>
    </refentryinfo>
    <refmeta>
        <refentrytitle>glGetMultisamplefv</refentrytitle>
        <manvolnum>3G</manvolnum>
    </refmeta>
    <refnamediv>
        <refname>glGetMultisamplefv</refname>
        <refpurpose>retrieve the location of a sample</refpurpose>
    </refnamediv>
    <refsynopsisdiv><title>C Specification</title>
        <funcsynopsis>
            <funcprototype>
                <funcdef>void <function>glGetMultisamplefv</function></funcdef>
                <paramdef>GLenum <parameter>pname</parameter></paramdef>
                <paramdef>GLuint <parameter>index</parameter></paramdef>
                <paramdef>GLfloat *<parameter>val</parameter></paramdef>
            </funcprototype>
        </funcsynopsis>
    </refsynopsisdiv>
    <refsect1 id="parameters"><title>Parameters</title>
        <variablelist>
        <varlistentry>
            <term><parameter>pname</parameter></term>
            <listitem>
                <para>
                    Specifies the sample parameter name. <parameter>pname</parameter> must be <constant>GL_SAMPLE_POSITION</constant>.
                </para>
            </listitem>
        </varlistentry>
        <varlistentry>
            <term><parameter>index</parameter></term>
            <listitem>
                <para>
                    Specifies the index of the sample whose position to query.
                </para>
            </listitem>
        </varlistentry>
        <varlistentry>
            <term><parameter>val</parameter></term>
            <listitem>
                <para>
                    Specifies the address of an array to receive the position of the sample.
                </para>
            </listitem>
        </varlistentry>
        </variablelist>
    </refsect1>
    <refsect1 id="description"><title>Description</title>
        <para>
            <function>glGetMultisamplefv</function> queries the location of
            a given sample. <parameter>pname</parameter> specifies the
            sample parameter to retrieve and must be
            <constant>GL_SAMPLE_POSITION</constant>.
            <parameter>index</parameter> corresponds to the sample for which
            the location should be returned. The sample location is returned
            as two floating-point values in <parameter>val[0]</parameter>
            and <parameter>val[1]</parameter>, each between 0 and 1,
            corresponding to the <parameter>x</parameter> and
            <parameter>y</parameter> locations respectively in the GL pixel
            space of that sample. (0.5, 0.5) this corresponds to the pixel
            center. <parameter>index</parameter> must be between zero and
            the value of <constant>GL_SAMPLES</constant> minus one.
        </para>
        <para>
            If the multisample mode does not have fixed sample locations, the returned values may only reflect the locations of samples
            within some pixels.
        </para>
    </refsect1>
    <refsect1 id="errors"><title>Errors</title>
        <para>
            <constant>GL_INVALID_ENUM</constant> is generated if <parameter>pname</parameter> is not one <constant>GL_SAMPLE_POSITION</constant>.
        </para>
        <para>
            <constant>GL_INVALID_VALUE</constant> is generated if <parameter>index</parameter> is greater than or equal to the value of
            <constant>GL_SAMPLES</constant>.
        </para>
    </refsect1>
    <refsect1 id="seealso"><title>See Also</title>
        <para>
            <citerefentry><refentrytitle>glGenFramebuffers</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glBindFramebuffer</refentrytitle></citerefentry>
        </para>
    </refsect1>
    <refsect1 id="Copyright"><title>Copyright</title>
        <para>
            Copyright <trademark class="copyright"></trademark> 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.
            <ulink url="http://opencontent.org/openpub/">http://opencontent.org/openpub/</ulink>.
        </para>
    </refsect1>
</refentry>
