[pstricks] perpendicular line similar to \Parallel (pst-optic)

[Patrick Drechsler]

Hi,

is there a function similar to `\Parallel' from the package
pst-optic for drawing perpendicular lines at a choosen position?

Something like:

\Perpendicular[<Options>](nodeA)(nodeB)(Start Node){Endnode}

My alternative approach trying to use `\rput' doesn't seem to
except nodes defined previously (`EN' in the example below):

--8<------------------------schnipp------------------------->8---
\documentclass[a4paper]{scrartcl}
\usepackage[latin1]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{pstricks-add,pst-node,pst-optic}
\begin{document}
{\centering%
  {\psset{xunit=\linewidth,yunit=.8\textheight}
    \begin{pspicture}(1,1)\psgrid
      %% Knoten:
      \pnode(.3,.35){Vk}
      \pnode(.7,.2){Hk}
      \pnode(.375,.35){D}
      \psline(Vk)(Hk)
      %% Force F_1
      \Parallel[linecolor=red,length=.3,arrows=->](Vk)(Hk)(D){EN}
      \rput(EN){$F_{1}$}
      %% Normalforce Fn
      \rput{90}(D){\psline(0,0)(EN)} %% <- Doesn't work
    \end{pspicture}
  }%
}
--8<------------------------schnapp------------------------->8---

If I replace the node `EN' with a numeric value everything's
fine. 

Thankful for any pointers,

Patrick

,----
|  *File List*
|     junk.tex
| scrartcl.cls    2002/09/18 v2.9j LaTeX2e KOMA document class
| scrlfile.sty    2002/09/18 v2.9j LaTeX2e KOMA package
|   size11.clo    2001/04/21 v1.4e Standard LaTeX file (size option)
| typearea.sty    2002/09/18 v2.9j LaTeX2e KOMA package
| inputenc.sty    2001/07/10 v0.99a Input encoding file 
|   latin1.def    2001/07/10 v0.99a Input encoding file 
|  fontenc.sty
|    t1enc.def    2001/06/05 v1.94 Standard LaTeX file
| pstricks-add.sty    2004/07/18 package wrapper for pstricks-add.tex (hv)
| pstricks.sty    2004/05/12 v0.2l LaTeX wrapper for `PSTricks' (RN,HV)
| pstricks.tex    2004/06/22 v1.04 `PSTricks' (tvz)
|   xcolor.sty    2004/07/04 v2.00 LaTeX color extensions (UK)
|    color.cfg    2001/08/31 v1.1 color configuration of teTeX/TeXLive
|    dvips.def    1999/02/16 v3.0i Driver-dependant file (DPC,SPQR)
| pstricks-add.tex    2004/10/16 v2.18 `PSTricks-add' (hv)
| pst-node.sty    2004/07/15 package wrapper for pst-node.tex
| pst-node.tex    2000/11/09 97 patch 11 `pst-node' (tvz)
| pst-optic.sty    2003/01/23 package wrapper for PSTricks pst-optic.tex
`----

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