根の形状

 根の形状を定義します。
 //**********************************************************************************
  #local Org_size = 4; #local Twig_Width = 1; #local Twn_size = 1;
  #local Torus_seg =
  object { torus { Org_size,Twig_Width sturm rotate -90*x }
          clipped_by { plane { x, 0 } rotate 180*z }
          clipped_by { plane { x, 0 } rotate 270*z }
  }
  #local Root_seg =
  union {
   object { Torus_seg }
   object { Torus_seg rotate 180*z translate 2*Org_size*y }
  translate Org_size*x }
  #local Cv1=< 0.242, 0.958, 0.242 >;
  #local Root =
  union {
   object { Root_seg rotate y*90*0 }
   object { Root_seg rotate y*90*1 }
   object { Root_seg rotate y*90*2 }
   object { Root_seg rotate y*90*3 }
  pigment { color rgb Cv1 } translate (-5*Org_size+0.470)*y }
 //**********************************************************************************