10.11.5 DrawFlatFacet



  \begin{texgraph}[name=DrawFlatFacet,export=pgf]
  Marges(0,0,0,0), size(7.5),
  theta:=75*deg, phi:=60*deg,
  S:=Cylindre(M(0,0,-4), 8*vecK, 2, 25, 0),
  C:= curveTube([3*exp(i*t),t/3],
          0.5, -2*pi, 2*pi, 75, 12,0),
  DrawFlatFacet(S,[color:=steelblue,
                   backculling:=1],
                C, [color:=crimson])
  \end{texgraph}

 PIC



DrawFlatFacet