<!DOCTYPE refentry [ <!ENTITY % mathent SYSTEM "math.ent"> %mathent; ]>

<!-- Converted by db4-upgrade version 1.1 -->

<refentry xmlns="http://docbook.org/ns/docbook" version="5.0" xml:id="glGetInternalformativ">
    <info>
        <copyright>
            <year>2011-2014</year>
            <holder>Khronos Group.</holder>
        </copyright>
    </info>
    <refmeta>
        <refentrytitle>glGetInternalformativ</refentrytitle>
        <manvolnum>3G</manvolnum>
    </refmeta>
    <refnamediv>
        <refname>glGetInternalformativ</refname>
        <refpurpose>retrieve information about implementation-dependent support for internal formats</refpurpose>
    </refnamediv>
    <refsynopsisdiv>
        <title>C Specification</title>
        <funcsynopsis>
            <funcprototype>
                <funcdef>void <function>glGetInternalformativ</function></funcdef>
                <paramdef>GLenum <parameter>target</parameter></paramdef>
                <paramdef>GLenum <parameter>internalformat</parameter></paramdef>
                <paramdef>GLenum <parameter>pname</parameter></paramdef>
                <paramdef>GLsizei <parameter>bufSize</parameter></paramdef>
                <paramdef>GLint *<parameter>params</parameter></paramdef>
            </funcprototype>
        </funcsynopsis>
    </refsynopsisdiv>
    <refsect1 xml:id="parameters"><title>Parameters</title>
        <variablelist>
        <varlistentry>
            <term><parameter>target</parameter></term>
            <listitem>
                <para>
                    Indicates the usage of the internal format. <parameter>target</parameter> must be <constant>GL_RENDERBUFFER</constant>.
                </para>
            </listitem>
        </varlistentry>
        <varlistentry>
            <term><parameter>internalformat</parameter></term>
            <listitem>
                <para>
                    Specifies the internal format about which to retrieve information.
                </para>
            </listitem>
        </varlistentry>
        <varlistentry>
            <term><parameter>pname</parameter></term>
            <listitem>
                <para>
                    Specifies the type of information to query.
                </para>
            </listitem>
        </varlistentry>
        <varlistentry>
            <term><parameter>bufSize</parameter></term>
            <listitem>
                <para>
                    Specifies the maximum number of integers that may be written to <parameter>params</parameter> by the function.
                </para>
            </listitem>
        </varlistentry>
        <varlistentry>
            <term><parameter>params</parameter></term>
            <listitem>
                <para>
                    Specifies the address of a variable into which to write the retrieved information.
                </para>
            </listitem>
        </varlistentry>
        </variablelist>
    </refsect1>
    <refsect1 xml:id="description"><title>Description</title>
        <para>
            <function>glGetInternalformativ</function> retrieves information about implementation-dependent support for
            internal formats. <parameter>target</parameter> indicates the target with which the internal format will
            be used and must be <constant>GL_RENDERBUFFER</constant>, corresponding to usage as a renderbuffer.
        </para>
        <para>
            <parameter>internalformat</parameter> specifies the internal format about which to retrieve information and
            must be a color-renderable, depth-renderable or stencil-renderable format.
        </para>
        <para>
            The information retrieved will be written to memory addressed by the pointer specified in <parameter>params</parameter>. No
            more than <parameter>bufSize</parameter> integers will be written to this memory.
        </para>
        <para>
            If <parameter>pname</parameter> is <constant>GL_NUM_SAMPLE_COUNTS</constant>, the number of sample counts that would be
            returned by querying <constant>GL_SAMPLES</constant> will be returned in <parameter>params</parameter>.
        </para>
        <para>
            If <parameter>pname</parameter> is <constant>GL_SAMPLES</constant>, the sample counts supported for <parameter>internalformat</parameter>
            and <parameter>target</parameter> are written into <parameter>params</parameter> in descending numeric order. Only positive values are returned.
            Querying <constant>GL_SAMPLES</constant> with <parameter>bufSize</parameter> of one will return just the maximum supported number of
            samples for this format.
        </para>
    </refsect1>
    <refsect1 xml:id="notes"><title>Notes</title>
        <para>
            Since multisampling is not supported for signed and unsigned integer internal
                        formats, the value of <constant>GL_NUM_SAMPLE_COUNTS</constant> will be zero for such formats.
                        If <parameter>internalformat</parameter> is <constant>GL_RGBA16F</constant>, <constant>GL_R32F</constant>,
                        <constant>GL_RG32F</constant>, or <constant>GL_RGBA32F</constant>, the value of <constant>GL_NUM_SAMPLE_COUNTS</constant>
                        may be zero, or else the maximum value in <constant>GL_SAMPLES</constant> may be less than the value of
                        <constant>GL_MAX_SAMPLES</constant>.
                        For every other accepted <parameter>internalformat</parameter>, the maximum value in <constant>GL_SAMPLES</constant> is guaranteed to be at least
                        <constant>GL_MAX_SAMPLES</constant>.
        </para>
    </refsect1>
    <refsect1 xml:id="errors"><title>Errors</title>
        <para>
            <constant>GL_INVALID_VALUE</constant> is generated if <parameter>bufSize</parameter> is negative.
        </para>
        <para>
            <constant>GL_INVALID_ENUM</constant> is generated if <parameter>pname</parameter> is not <constant>GL_SAMPLES</constant> or <constant>GL_NUM_SAMPLE_COUNTS</constant>.
        </para>
        <para>
            <constant>GL_INVALID_ENUM</constant> is generated if <parameter>internalformat</parameter> is not color-, depth-, or stencil-renderable.
        </para>
        <para>
            <constant>GL_INVALID_ENUM</constant> is generated if <parameter>target</parameter> is not <constant>GL_RENDERBUFFER</constant>.
        </para>
    </refsect1>
    <refsect1 xml:id="versions">
        <title>API Version Support</title>
        <informaltable>
            <tgroup cols="4" align="left">
                <xi:include xmlns:xi="http://www.w3.org/2001/XInclude" href="apifunchead.xml" xpointer="xpointer(/*/*)"/>
                <tbody>
                    <row>
                        <entry>glGetInternalformativ</entry>
                        <xi:include xmlns:xi="http://www.w3.org/2001/XInclude" href="apiversion.xml" xpointer="xpointer(/*/*[@role='es30']/*)"/>
                    </row>
                </tbody>
            </tgroup>
        </informaltable>
    </refsect1>
    <refsect1 xml:id="seealso"><title>See Also</title>
        <para>
            <citerefentry><refentrytitle>glGet</refentrytitle></citerefentry>
        </para>
    </refsect1>
    <refsect1 xml:id="Copyright"><title>Copyright</title>
        <para>
            Copyright <trademark class="copyright"/> 2011-2014 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>
