<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE concept PUBLIC "-//OASIS//DTD DITA Concept//EN" "concept.dtd">
<concept id="about_pdftransformation"> 
  <title>Understanding PDF Transformations</title> 
  <shortdesc>Learning how DITA OT uses the FO plugin to generate PDF documents.
  </shortdesc>
  <prolog>
  <author>Rob Justice</author>
    <metadata>
      <keywords>
        <indexterm>FO Plugin</indexterm><indexterm>PDF transformations</indexterm>
      </keywords>
    </metadata>
  </prolog>  
  <conbody>
  <p>DITA-OT performs PDF transformations differently than other output types.  A separate software program, known as XSL formatter, is used
	to generate the PDF documents.  By default, that engine is the FO Plugin, which also uses an Ant build script to generates several files and 
	place them in the directory you specify with the <codeph>dita.temp.dir</codeph> property in your script.  Several of these files are useful for 
	debugging PDF-related transformation errors.  However, the FO Plugin build script also deletes them by default. You can override this behavior 
	by setting the value of the <codeph>clean.temp</codeph> ant property in your build script to "no," as shown in the following code snippet.
	<codeblock>&lt; property name="clean.temp" value="no"/></codeblock></p>
  <note>The FO Plugin ant build script is located in the
      following directory: <codeph>DITA-OT<keyword keyref="release.version"/>\demo\fo\build.xml</codeph>.</note>
  <p>The following table describes the auto-generated files relevant to debugging PDF transformation errors.</p>
  <table>
  <tgroup cols="2">
  <colspec colname="COLSPEC10" colwidth="150*"/>
  <colspec colname="COLSPEC11" colwidth="250*"/>
  <thead>
  <row>
	<entry colname="COLSPEC10" valign="top">File Name</entry>
	<entry colname="COLSPEC11" valign="top">Description</entry>
  </row>
  </thead>
  <tbody>
  <row>
  <entry>
  <p><codeph>stage1.xml</codeph></p>
  </entry>
  <entry>
  Contains FO processing information related to your index entries.
  </entry>
  </row>
  <row>
  <entry>
  <codeph>stage2.fo</codeph>, <codeph>stage3.fo</codeph>
  </entry>
  <entry>
  Contains FO processing information related to your internationalization files.
  </entry>
  </row>
  <row>
  <entry>
  <codeph>buildfile_MERGED.xml</codeph>
  </entry>
  <entry>
  Contains all the processing information from the generated files and your content in a format that the FO Plugin can use
  to generate your PDF file.
  </entry>
  </row>
  </tbody>
  </tgroup>
  </table>
  <p>Examine the content of these files to determine the cause of PDF transformation errors.</p>
  <note>The Apache FOP formatter does not support the <codeph>indexlist</codeph> element for PDF.
  You can try using a different PDF renderer or engine by specifying a different value for the <codeph>
  pdf.formatter</codeph> ant property in the FO plugin build file, or add a <codeph>topicref</codeph> element
  in your build file with that links to a manually-created index file.</note>
  </conbody>
  </concept>