isosurface { //------------------------------------------------

  function{
   f_sphere(x, y, z, 1.8) - (-f_snoise3d(x*1.5, y*1, z*1)*2.25) 

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

  texture{ pigment{ color rgb<0.65,0.3,0.15>*0.7}
           finish { phong 1 reflection 0.05}}

  scale 0.5
  rotate<0,20,0>
  translate <-0.2, 1.3, 0>
} // end of isosurface ----------------------------------------