小枝の形状

 柿に付いている小枝の形状を定義します。
 //**********************************************************************************
  #local Tr=30; #local Lw=1; #local Ra1=-70; #local Ra2=70;
  #local Twig_org =
   torus { Tr,Lw
   clipped_by { plane { z, 0 } rotate (Ra1)*y }
   clipped_by { plane { z, 0 } rotate (Ra2)*y }
   translate Tr*z rotate -90*x }
  #local Twig_seg =
  union {
   object { Twig_org }
   object { Twig_org rotate 180*z
      translate < Tr*cos(radians(Ra2))*2,(Tr-Tr*sin(radians(Ra2)))*2,0> }
   object { Twig_org rotate 180*z
      translate <-Tr*cos(radians(Ra2))*2,(Tr-Tr*sin(radians(Ra2)))*2,0> }
   cone { 0, Lw*2.5, <0,-6,0>, Lw }
  scale < 0.5,1,1 > translate 6*y }
 //**********************************************************************************