Custom artwork
The common/artwork folder houses custom artwork files that override the standard icons in org.dita.pdf2/cfg/common/artwork.
These files are used to graphically identify different types of DITA note element.
The mapping between note type and graphic is contained in the common variables file org.dita.pdf2/cfg/common/vars/commonvariables.xml.
The variables that control note graphics all follow the form
<variable id="\{type\} Note Image Path"> \{path to image file\} </variable>
where {type} contains a possible value for the note @type attribute and {path to image file} is the path to the note icon image.