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<refentry xmlns="http://docbook.org/ns/docbook" version="5.0" xml:id="glGetSamplerParameter">
    <info>
        <copyright>
            <year>2010-2013</year>
            <holder>Khronos Group</holder>
        </copyright>
    </info>
    <refmeta>
        <refentrytitle>glGetSamplerParameter</refentrytitle>
        <manvolnum>3G</manvolnum>
    </refmeta>
    <refnamediv>
        <refname>glGetSamplerParameter</refname>
        <refpurpose>return sampler parameter values</refpurpose>
    </refnamediv>
    <refsynopsisdiv><title>C Specification</title>
        <funcsynopsis>
            <funcprototype>
                <funcdef>void <function>glGetSamplerParameterfv</function></funcdef>
                <paramdef>GLuint <parameter>sampler</parameter></paramdef>
                <paramdef>GLenum <parameter>pname</parameter></paramdef>
                <paramdef>GLfloat * <parameter>params</parameter></paramdef>
            </funcprototype>
        </funcsynopsis>
        <funcsynopsis>
            <funcprototype>
                <funcdef>void <function>glGetSamplerParameteriv</function></funcdef>
                <paramdef>GLuint <parameter>sampler</parameter></paramdef>
                <paramdef>GLenum <parameter>pname</parameter></paramdef>
                <paramdef>GLint * <parameter>params</parameter></paramdef>
            </funcprototype>
        </funcsynopsis>
        <funcsynopsis>
            <funcprototype>
                <funcdef>void <function>glGetSamplerParameterIiv</function></funcdef>
                <paramdef>GLuint <parameter>sampler</parameter></paramdef>
                <paramdef>GLenum <parameter>pname</parameter></paramdef>
                <paramdef>GLint * <parameter>params</parameter></paramdef>
            </funcprototype>
        </funcsynopsis>
        <funcsynopsis>
            <funcprototype>
                <funcdef>void <function>glGetSamplerParameterIuiv</function></funcdef>
                <paramdef>GLuint <parameter>sampler</parameter></paramdef>
                <paramdef>GLenum <parameter>pname</parameter></paramdef>
                <paramdef>GLuint * <parameter>params</parameter></paramdef>
            </funcprototype>
        </funcsynopsis>
    </refsynopsisdiv>
    <refsect1 xml:id="parameters"><title>Parameters</title>
        <variablelist>
        <varlistentry>
            <term><parameter>sampler</parameter></term>
            <listitem>
                <para>
                    Specifies name of the sampler object from which to retrieve parameters.
                </para>
            </listitem>
        </varlistentry>
        <varlistentry>
            <term><parameter>pname</parameter></term>
            <listitem>
                <para>
                    Specifies the symbolic name of a sampler parameter.
                    <constant>GL_TEXTURE_MAG_FILTER</constant>,
                    <constant>GL_TEXTURE_MIN_FILTER</constant>,
                    <constant>GL_TEXTURE_MIN_LOD</constant>,
                    <constant>GL_TEXTURE_MAX_LOD</constant>,
                    <constant>GL_TEXTURE_LOD_BIAS</constant>,
                    <constant>GL_TEXTURE_WRAP_S</constant>,
                    <constant>GL_TEXTURE_WRAP_T</constant>,
                    <constant>GL_TEXTURE_WRAP_R</constant>,
                    <constant>GL_TEXTURE_BORDER_COLOR</constant>,
                    <constant>GL_TEXTURE_COMPARE_MODE</constant>, and
                    <constant>GL_TEXTURE_COMPARE_FUNC</constant>
                    are accepted.
                </para>
            </listitem>
        </varlistentry>
        <varlistentry>
            <term><parameter>params</parameter></term>
            <listitem>
                <para>
                    Returns the sampler parameters.
                </para>
            </listitem>
        </varlistentry>
        </variablelist>
    </refsect1>
    <refsect1 xml:id="description"><title>Description</title>
        <para>
            <function>glGetSamplerParameter</function> returns in <parameter>params</parameter> the value or values of the sampler parameter
            specified as <parameter>pname</parameter>.
            <parameter>sampler</parameter> defines the target sampler, and must be the name of an existing sampler object, returned from a previous call
            to <citerefentry><refentrytitle>glGenSamplers</refentrytitle></citerefentry>.
            <parameter>pname</parameter> accepts the same symbols as <citerefentry><refentrytitle>glSamplerParameter</refentrytitle></citerefentry>,
            with the same interpretations:
        </para>
        <variablelist>
            <varlistentry>
                <term><constant>GL_TEXTURE_MAG_FILTER</constant></term>
                <listitem>
                    <para>
                        Returns the single-valued texture magnification filter,
                        a symbolic constant. The initial value is <constant>GL_LINEAR</constant>.
                    </para>
                </listitem>
            </varlistentry>
            <varlistentry>
                <term><constant>GL_TEXTURE_MIN_FILTER</constant></term>
                <listitem>
                    <para>
                        Returns the single-valued texture minification filter,
                        a symbolic constant. The initial value is <constant>GL_NEAREST_MIPMAP_LINEAR</constant>.
                    </para>
                </listitem>
            </varlistentry>
            <varlistentry>
                <term><constant>GL_TEXTURE_MIN_LOD</constant></term>
                <listitem>
                    <para>
                        Returns the single-valued texture minimum level-of-detail value.  The
                        initial value is
                        <inlineequation><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                            <!-- eqn: -1000: -->
                            <mml:mn>-1000</mml:mn>
                        </mml:math></inlineequation>.
                    </para>
                </listitem>
            </varlistentry>
            <varlistentry>
                <term><constant>GL_TEXTURE_MAX_LOD</constant></term>
                <listitem>
                    <para>
                        Returns the single-valued texture maximum level-of-detail value. The
                        initial value is 1000.
                    </para>
                </listitem>
            </varlistentry>
            <varlistentry>
                <term><constant>GL_TEXTURE_WRAP_S</constant></term>
                <listitem>
                    <para>
                        Returns the single-valued wrapping function for texture coordinate
                        <inlineequation><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">s</mml:mi></mml:math></inlineequation>,
                        a symbolic constant. The initial value is <constant>GL_REPEAT</constant>.
                    </para>
                </listitem>
            </varlistentry>
            <varlistentry>
                <term><constant>GL_TEXTURE_WRAP_T</constant></term>
                <listitem>
                    <para>
                        Returns the single-valued wrapping function for texture coordinate
                        <inlineequation><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">t</mml:mi></mml:math></inlineequation>,
                        a symbolic constant. The initial value is <constant>GL_REPEAT</constant>.
                    </para>
                </listitem>
            </varlistentry>
            <varlistentry>
                <term><constant>GL_TEXTURE_WRAP_R</constant></term>
                <listitem>
                    <para>
                        Returns the single-valued wrapping function for texture coordinate
                        <inlineequation><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">r</mml:mi></mml:math></inlineequation>,
                        a symbolic constant. The initial value is <constant>GL_REPEAT</constant>.
                    </para>
                </listitem>
            </varlistentry>
            <varlistentry>
                <term><constant>GL_TEXTURE_BORDER_COLOR</constant></term>
                <listitem>
                    <para>
                        Returns four integer or floating-point numbers that comprise the RGBA color
                        of the texture border.
                        Floating-point values are returned in the range
                        <inlineequation><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                            <!-- eqn: [0,1]: -->
                            <mml:mfenced open="[" close="]">
                                <mml:mn>0</mml:mn>
                                <mml:mn>1</mml:mn>
                            </mml:mfenced>
                        </mml:math></inlineequation>.
                        Integer values are returned as a linear mapping of the internal floating-point
                        representation such that 1.0 maps to the most positive representable
                        integer and
                        <inlineequation><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                            <!-- eqn: -1.0: -->
                            <mml:mn>-1.0</mml:mn>
                        </mml:math></inlineequation>
                        maps to the most negative representable
                        integer. The initial value is (0, 0, 0, 0).
                    </para>
                </listitem>
            </varlistentry>
            <varlistentry>
                <term><constant>GL_TEXTURE_COMPARE_MODE</constant></term>
                <listitem>
                    <para>
                        Returns a single-valued texture comparison mode, a symbolic constant.  The
                        initial value is <constant>GL_NONE</constant>. See <citerefentry><refentrytitle>glSamplerParameter</refentrytitle></citerefentry>.
                    </para>
                </listitem>
            </varlistentry>
            <varlistentry>
                <term><constant>GL_TEXTURE_COMPARE_FUNC</constant></term>
                <listitem>
                    <para>
                        Returns a single-valued texture comparison function, a symbolic constant.  The
                        initial value is <constant>GL_LEQUAL</constant>. See <citerefentry><refentrytitle>glSamplerParameter</refentrytitle></citerefentry>.
                    </para>
                </listitem>
            </varlistentry>
        </variablelist>
    </refsect1>
    <refsect1 xml:id="notes"><title>Notes</title>
        <para>
            If an error is generated,
            no change is made to the contents of <parameter>params</parameter>.
        </para>
        <para>
            <function>glGetSamplerParameter</function> is available only if the GL version is 3.3 or higher.
        </para>
    </refsect1>
    <refsect1 xml:id="errors"><title>Errors</title>
        <para>
            <constant>GL_INVALID_VALUE</constant> is generated if <parameter>sampler</parameter> is not the name of a sampler object returned from
            a previous call to <citerefentry><refentrytitle>glGenSamplers</refentrytitle></citerefentry>.
        </para>
        <para>
            <constant>GL_INVALID_ENUM</constant> is generated if <parameter>pname</parameter> is not an accepted value.
        </para>
    </refsect1>
    <refsect1 xml:id="seealso"><title>See Also</title>
        <para>
            <citerefentry><refentrytitle>glSamplerParameter</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glGenSamplers</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glDeleteSamplers</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glSamplerParameter</refentrytitle></citerefentry>
        </para>
    </refsect1>
    <refsect1 xml:id="Copyright"><title>Copyright</title>
        <para>
            Copyright <trademark class="copyright"/> 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.
            <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://opencontent.org/openpub/">http://opencontent.org/openpub/</link>.
        </para>
    </refsect1>
</refentry>
