cercle_04.tex

\documentclass{article}
\usepackage[dvipsnames,svgnames]{pstricks}
\usepackage{pst-solides3d}
\begin{document}
\pagestyle{empty}
 
\begin{pspicture}(-4,-4)(5,4)%
\psframe*[linecolor=blue!50](-4,-4)(5,4)%
\psset{lightsrc=viewpoint,viewpoint=50 30 15,Decran=60}
\psset{solidmemory}
%% definition du plan de projection
\psSolid[object=plan,
   definition=equation,
   args={[1 0 0 0] 90},
   base=-4.2 4.2 -3.2 3.2,
   fillcolor=white,
   linecolor=gray!40,
   plangrid,
   planmarks,
   name=monplan,
]
\psset{plan=monplan,fontsize=15}
\codejps{
%% syntaxe : A B C cerclecirconscrit --> I r
/cerclecirconscrit {
5 dict begin
   /C defpoint
   /B defpoint
   /A defpoint
   B C mediatrice /d1 defdroite
   C A mediatrice /d2 defdroite
   d1 d2 interdroite /I defpoint
   I I A distance 
end
} def
}
\psProjection[object=point,name=A,text=A,pos=ul](1,0)
\psProjection[object=point,name=B,text=B,pos=br](2,-1)
\psProjection[object=point,name=C,text=C,pos=bl](0.5,-1)
\psProjection[object=polygone,args=A B C,name=P]
\psProjection[object=cercle,range=0 360,definition=cerclecirconscrit,args=A B C]
\composeSolid
\end{pspicture}
 
\end{document}