# How to show auxiliary points for any curves defined in a pscustom?

I need to show the auxiliary points of any curves defined in pscustom such that I can easily locate the points during the development process.

The following MWE is my attempt to show such points, but fails.

\documentclass[pstricks,margin=1cm,preview]{standalone}

\begin{document}
\begin{pspicture}[showgrid](-6,-6)(6,6)
\pscustom[showpoints=true]
{
\psline(-4,-4)(-4,4)(4,4)(4,-4)
\closepath
}
\end{pspicture}
\end{document}


\documentclass[pstricks,margin=1cm,preview]{standalone}

• I suppose you mean dots. Right? A line is a line, there are no auciliary points. If you want to see the dots use the coordinates also outside \pscustom: \psdots(-4,-4)(-4,4)(4,4)(4,-4) – user2478 Sep 29 '16 at 18:07