src/references/instructions/server/drawing/clip.xml

<?xml version="1.0" encoding="UTF-8"?>

<section xml:id="clip-instruction" 
    xmlns="http://docbook.org/ns/docbook" version="5.0" xml:lang="en"
    xmlns:xi="http://www.w3.org/2001/XInclude">
    <title>clip</title>

    <indexterm>
        <primary>clip</primary>
    </indexterm>
    <para>Applies the current path as the clipping path. Future operations will
        only draw within the current path. Note that future clip instructions
        will also be limited by this path. To set a completely new clipping path,
        you must first reset the layer with a reset instruction. If you wish to
        only reset the clipping path, but preserve the current transform matrix,
        push the layer state before setting the clipping path, and pop the layer
        state to reset.</para>
    <variablelist>
        <varlistentry>
            <term><parameter>layer</parameter></term>
            <listitem>
                <para>The layer whose clipping path should be set.</para>
            </listitem>
        </varlistentry>
    </variablelist>

</section>