// FUNCTION - FUNCTIONS by ISOSURFACE / Dancing in a Circle '02.07
// By Tsutomu HIGO  E-mail: nj2t-hg@asahi-net.or.jp

#version 3.5;
global_settings {
  max_trace_level 3
  assumed_gamma 2.2
  }

camera {
  location <-3, 10, -12>
  look_at <-0.1, 0, 0>
  angle 15
  }

light_source {< 0, 0, 0> color rgb <0, 0, 1>}
light_source {<0, 5, -10> color rgb <1, 1, 1>}

isosurface {
  function {(y+0.1*pow(x*x+z*z,0.2)*sin(24*atan(z/x)-24*pi/(x*x+z*z+1))
            -6/(x*x+z*z+1))*(y+1.45-6/(x*x+z*z+1))+0.6}
  threshold 0
  max_gradient 18
  contained_by {box {<-7, -5, -7>, <7, 5, 7>}}
  open
  texture {
    pigment {color rgb <0.6, 0.7, 1>}
    finish {
      ambient 0.5
      diffuse 1
      phong 1
      phong_size 20
      specular 0.5
      roughness 0.02
      brilliance 0.5
      }
    }
  scale 1/vlength(1)
  no_shadow
  rotate <-15, 0, -15>
  }