isosurface { //--------------------------------------
  function{
   f_sphere(x, y, z, 2.2)
   - ( -f_snoise3d(x*2, y*2, z*2)*0.75 )

  }
  contained_by { sphere {<0,0,0>, -3.3 } }
  accuracy 0.003
  max_gradient 5

  texture{ pigment{ color rgb<0.8,0.6,0.5> }
           finish { phong 1 }}
  scale 0.55 
  rotate<0,20,0>
  translate < 0, 1.3, 0>
} // end of isosurface ------------------------------