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<refentry id="glInvalidateSubFramebuffer">
    <refmeta>
        <refmetainfo>
            <copyright>
                <year>2012</year>
                <holder>Khronos Group</holder>
            </copyright>
        </refmetainfo>
        <refentrytitle>glInvalidateSubFramebuffer</refentrytitle>
        <manvolnum>3G</manvolnum>
    </refmeta>
    <refnamediv>
        <refname>glInvalidateSubFramebuffer</refname>
        <refpurpose>invalidate the content of a region of some or all of a framebuffer object's attachments</refpurpose>
    </refnamediv>
    <refsynopsisdiv><title>C Specification</title>
        <funcsynopsis>
            <funcprototype>
                <funcdef>void <function>glInvalidateSubFramebuffer</function></funcdef>
                <paramdef>GLenum <parameter>target</parameter></paramdef>
                <paramdef>GLsizei <parameter>numAttachments</parameter></paramdef>
                <paramdef>const GLenum * <parameter>attachments</parameter></paramdef>
                <paramdef>GLint <parameter>x</parameter></paramdef>
                <paramdef>GLint <parameter>y</parameter></paramdef>
                <paramdef>GLint <parameter>width</parameter></paramdef>
                <paramdef>GLint <parameter>height</parameter></paramdef>
            </funcprototype>
        </funcsynopsis>
    </refsynopsisdiv>
    <refsect1 id="parameters"><title>Parameters</title>
        <variablelist>
        <varlistentry>
            <term><parameter>target</parameter></term>
            <listitem>
                <para>
                    The target to which the framebuffer is attached. <parameter>target</parameter> must be
                    <constant>GL_FRAMEBUFFER</constant>, <constant>GL_DRAW_FRAMEBUFFER</constant>, or <constant>GL_READ_FRAMEBUFFER</constant>.
                </para>
            </listitem>
        </varlistentry>
        <varlistentry>
            <term><parameter>numAttachments</parameter></term>
            <listitem>
                <para>
                    The number of entries in the <parameter>attachments</parameter> array.
                </para>
            </listitem>
        </varlistentry>
        <varlistentry>
            <term><parameter>attachments</parameter></term>
            <listitem>
                <para>
                    The address of an array identifying the attachments to be invalidated.
                </para>
            </listitem>
        </varlistentry>
        <varlistentry>
            <term><parameter>x</parameter></term>
            <listitem>
                <para>
                    The X offset of the region to be invalidated.
                </para>
            </listitem>
        </varlistentry>
        <varlistentry>
            <term><parameter>y</parameter></term>
            <listitem>
                <para>
                    The Y offset of the region to be invalidated.
                </para>
            </listitem>
        </varlistentry>
        <varlistentry>
            <term><parameter>width</parameter></term>
            <listitem>
                <para>
                    The width of the region to be invalidated.
                </para>
            </listitem>
        </varlistentry>
        <varlistentry>
            <term><parameter>height</parameter></term>
            <listitem>
                <para>
                    The height of the region to be invalidated.
                </para>
            </listitem>
        </varlistentry>
        </variablelist>
    </refsect1>
    <refsect1 id="description"><title>Description</title>
        <para>
            <function>glInvalidateSubFramebuffer</function> invalidates the content of a region
            of a specified set of attachments of a framebuffer. The framebuffer
            whose content to invalidate is indicated by setting <parameter>target</parameter>
            to the target to which it is bound. <parameter>target</parameter> may be
            <constant>GL_FRAMEBUFFER</constant>, <constant>GL_READ_FRAMEBUFFER</constant> or
            <constant>GL_DRAW_FRAMEBUFFER</constant>. <constant>GL_FRAMEBUFFER</constant>
            is treated as if it were <constant>GL_DRAW_FRAMEBUFFER</constant>.
        </para>
        <para>
            A region within a subset of the framebuffer's attachments may be invalidated.
            This set of attachments are specified in an array whose address is given
            by <parameter>attachments</parameter> and which contains <parameter>numAttachments</parameter>
            elements. The elements of <parameter>attachments</parameter> must be
            <constant>GL_DEPTH_ATTACHMENT</constant>, <constant>GL_STENCIL_ATTACHMENT</constant>
            <constant>GL_DEPTH_STENCIL_ATTACHMENT</constant>, or <constant>GL_COLOR_ATTACHMENT<emphasis>i</emphasis></constant>,
            where <emphasis>i</emphasis> is between zero and the value of <constant>GL_MAX_FRAMEBUFFER_ATTACHMENTS</constant> minus one.
            Furthermore, if the default framebuffer is bound to <parameter>target</parameter>, then
            <parameter>attachments</parameter> may contain <constant>GL_FRONT_LEFT</constant>,
            <constant>GL_FRONT_RIGHT</constant>, <constant>GL_BACK_LEFT</constant>, <constant>GL_BACK_RIGHT</constant>,
            <constant>GL_AUX<emphasis>i</emphasis></constant>, <constant>GL_ACCUM</constant>,
            <constant>GL_COLOR</constant>, <constant>GL_DEPTH</constant>, or <constant>GL_STENCIL</constant>, identifying that specific buffer.
            <constant>GL_COLOR</constant>, is treated as <constant>GL_BACK_LEFT</constant> for a double-buffered context and
            <constant>GL_FRONT_LEFT</constant> for a single-buffered context.
        </para>
        <para>
            The region of the framebuffer attachments to be invalidated is specified
            by <parameter>x</parameter>, <parameter>y</parameter>, <parameter>width</parameter> and <parameter>height</parameter>
            where <parameter>x</parameter> and <parameter>y</parameter> give the offset from the origin (with
            lower-left corner at (0, 0)) and <parameter>width</parameter> and <parameter>height</parameter>
            give the size. Any pixels lying outside of the window allocated
            to the current GL context, or outside of the attachments of the currently
            bound framebuffer object, are ignored.
            After <function>glInvalidateFramebuffer</function> is executed, the contents
            of the specified region of the specified attachments become undefined.
        </para>
    </refsect1>
    <refsect1 id="errors"><title>Errors</title>
        <para>
            <constant>GL_INVALID_ENUM</constant> is generated if <parameter>target</parameter> is not one of the
            accepted framebuffer target tokens.
        </para>
        <para>
            <constant>GL_INVALID_ENUM</constant> is generated if any element of <parameter>attachments</parameter> is
            not one of the accepted framebuffer attachment tokens.
        </para>
        <para>
            <constant>GL_INVALID_OPERATION</constant> is generated if element of <parameter>attachments</parameter> is
            <constant>GL_COLOR_ATTACHMENT<emphasis>i</emphasis></constant> where <emphasis>i</emphasis> is greater than or equal
            to the value of <constant>GL_MAX_COLOR_ATTACHMENTS</constant>.
        </para>
    </refsect1>
    <refsect1 id="associatedgets"><title>Associated Gets</title>
        <para>
            <citerefentry><refentrytitle>glGet</refentrytitle></citerefentry> with argument <constant>GL_MAX_COLOR_ATTACHMENTS</constant>
        </para>
    </refsect1>
    <refsect1 id="seealso"><title>See Also</title>
        <para>
            <citerefentry><refentrytitle>glInvalidateTexSubImage</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glInvalidateTexImage</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glInvalidateBufferSubData</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glInvalidateBufferData</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glInvalidateFramebuffer</refentrytitle></citerefentry>.
        </para>
    </refsect1>
    <refsect1 id="Copyright"><title>Copyright</title>
        <para>
            Copyright <trademark class="copyright"></trademark> 2012 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>
