11.2.3 bdAngleD



  \begin{texgraph}[name=bdAngleD,export=pgf]
  Marges(0,0,0,0), view(-3,3,-3,3),
  view3D(-3,3,-3,3,-3,3), size(7.5),
  background(full, gray),
  B:=M(0,2,0), A:=M(0,0,0),C:=M(0,0,1.5),
  Build3D(
   bdAngleD(B,A,C,1, [color:=firebrick,tube:=1]),
   bdDot([A,B,C], [dotstyle:=cube,
                   dotscale:=0.85,
                   color:=forestgreen]),
   bdArc(B,A,C,2,1,[color:=blue, width:=12,
                   arrows:=1,labelarc("$\pi/2$")]),
   bdAxes([0,0], [color:=gold,arrows:=1]),
   bdLabel(B,"$B$",[labelpos:=[0.5,-i]]),
   bdLabel(C,"$C$",[labelpos:=[0.5,-1]]),
         ),
  Display3D()
  \end{texgraph}

 PIC



bdAngleD