[pstricks] Calculer distances entre nœuds avec Pstricks

[Herbert Voss]

agodemar schrieb:

> Thank you for this code above, but I think you understand now that my
> problem
> is a little bit more general: I would like to measure things coming
> from outside
> using psfrag and pstricks (and fp if necessary).

there is an easy but not short solution, you have to rewrite
the existing macros:

\psArc[options]{arrows}(center)(node B for radius A-B){alpha}{beta}

[options] and {arrows} are both optional.

Herbert

\documentclass[12pt,a4paper]{article}
\usepackage[dvips,svgnames,x11names]{pstricks}
\usepackage{pst-eucl}

\makeatletter
\def\psArc{\pst at object{psArc}}
\def\psArc at i{\@ifnextchar({\psArc at iii}{\psArc at ii}}
\def\psarc at ii#1{\addto at par{arrows=#1}%
   \@ifnextchar({\psArc at iii}{\psArc at iii(0,0)}%
}
\def\psArc at iii(#1)(#2)#3#4{%
   \begin at OpenObj
     \pst at getangle{#3}\pst at tempa
     \pst at getangle{#4}\pst at tempb
     \ifx\pst at tempa\pst at tempb \else
       \pst@@getcoor{#1}%
       \addto at pscode{\psArc at iv{#1}{#2} \psarc at v}%
       \gdef\psarc at type{0}%
       \showpointsfalse
     \fi
   \end at OpenObj%
}
\def\psArc at iv#1#2{%
   \pst at coor /y ED /x ED
   /r \pstDistAB{#1}{#2} def
   /c 57.2957 r \tx at Div def
   /angleA
     \pst at tempa
     \psk at arcsepA c mul 2 div
     \ifcase\psarc at type add \or sub \fi
   def
   /angleB
     \pst at tempb
     \psk at arcsepB c mul 2 div
     \ifcase\psarc at type sub \or add \fi
   def
   \ifshowpoints\psarc at showpoints\fi
   \ifx\psk at arrowA\@empty
     \ifnum\psk at liftpen=2
       r angleA \tx at PtoC
       y add exch x add exch moveto
     \fi
   \fi}

\makeatother
\begin{document}

\begin{pspicture}[showgrid=true](-5,-5)(5,5)
\pnode(1,0){A}
\pnode(3,3){B}
\psArc(A)(B){215}{-40}
\qdisk(A){2pt}
\qdisk(B){2pt}
\end{pspicture}

\end{document}