<?xml version="1.0" encoding="utf-8"?>
<section version="5.0"
         xsi:schemaLocation="http://docbook.org/ns/docbook http://docbook.org/xml/5.0/xsd/docbook.xsd"
         xml:id="particles.modifiers.expand_selection"
         xmlns="http://docbook.org/ns/docbook"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xmlns:xs="http://www.w3.org/2001/XMLSchema"
         xmlns:xlink="http://www.w3.org/1999/xlink"
         xmlns:xi="http://www.w3.org/2001/XInclude"
         xmlns:ns="http://docbook.org/ns/docbook">
  <title>Expand selection</title>

  <para>
 
    <informalfigure><screenshot><mediaobject><imageobject>
       <imagedata fileref="images/modifiers/expand_selection_panel.png" format="PNG" />
    </imageobject></mediaobject></screenshot></informalfigure>

    Expands the current particle selection by selecting particles that are neighbors 
    of already selected particles. You can choose between three different modes:
    <orderedlist>
    <listitem><para>A cutoff radius can be specified to select particles that are within
    a specific maximum range of already selected particles.</para></listitem>
    <listitem><para>The modifier can select particles that are among the <emphasis>N</emphasis> nearest neighbors
    of an already selected particle. The number <emphasis>N</emphasis> is adjustable.</para></listitem>
    <listitem><para>If the system contains particle bonds, the modifier can expand the selection
    to particles that are bonded to at least one particle that is already selected.</para></listitem>
    </orderedlist>
    
  </para>

  <simplesect>
    <title>Parameters</title>

    <variablelist>
      <varlistentry>
        <term>Cutoff distance</term>
        <listitem>
          <para>A particle will be selected if it is within this range of an already selected particle.</para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term>N</term>
        <listitem>
          <para>The number of nearest neighbors to select around each already selected particle.
          OVITO sorts the list of neighbors of a selected particle by ascending distance and selects the leading <emphasis>N</emphasis> entries 
          from the list.</para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term>Number of iterations</term>
        <listitem>
          <para>This parameter allows you to expand the selection in multiple recursive steps.
          For example, setting this parameter to a value of 2 will expand the current selection to the second shell of neighbors,
          as if the modifier had been applied twice.</para>
        </listitem>
      </varlistentry>

    </variablelist>
  </simplesect>
</section>
