The parameter for \Index{drawing} comes with the key value \Lkeyword{action} within the command
\Lcs{psSolid}.
Four values are possible:
\begin{compactitem}
\item \Lkeyval{none}: nothing is drawn.
\item \Lkeyval{draw}: draws the solid as a framework and sets up dashed lines for the hidden edges.
\item \Lkeyval{draw*}: draws the solid with dashed lines for the hidden edges and colours the visible faces.
\item \Lkeyword{draw**}: draws the solid with a painting algorithm, without the
hidden edges and with colouration of the visible faces.
\end{compactitem}
\encadre{The key values \Lkeyval{draw} and \Lkeyword{draw*} only make sense for convex solids.}
