// CASSINI / Exchanging coordinates - Compressing rotation '03.05
// By Tsutomu HIGO  E-mail: nj2t-hg@asahi-net.or.jp

#version 3.5;
global_settings {
  max_trace_level 4
  assumed_gamma 2.2
  }

camera {
  location <4, 30, -30>
  look_at <0, -0.2, 0>
  angle 10
  }

light_source {<-50, 150, -75> color rgb <0.8, 0.8, 0.8>}

isosurface {
  function {pow(pow(cos(2*atan(z/x))*x-sin(2*atan(z/x))*z,2)
    +8*y*y+pow(sin(2*atan(z/x))*x+cos(2*atan(z/x))*z,2),2)
    -0.99*4*pow(cos(2*atan(z/x))*x-sin(2*atan(z/x))*z,2)
    *pow(sin(2*atan(z/x))*x+cos(2*atan(z/x))*z,2)-pow(2,4)}
  threshold 1
  max_gradient 2000
  contained_by {box {<-7, -0.8, -7>, <7, 0.8, 7>}}
  //open
  texture {
    pigment {color rgb <1, 1, 0.5>}
    finish {
      ambient 0.2
      diffuse 1
      reflection 0.5
      specular 1
      phong 0.5
      brilliance 1
      }
    }
  scale 1/vlength(1)
  rotate <0, 0, 0>
  no_shadow
  }

background {color rgb <0, 0.2, 0.7>}