// TWIST / A Propeller '02.10
// By Tsutomu HIGO  E-mail: nj2t-hg@asahi-net.or.jp

#version 3.5;
global_settings {
  max_trace_level 5
  assumed_gamma 2.2
  }

#include "functions.inc"

isosurface {
  function {
    ((cos(-pi*y/2)*x-sin(-pi*y/2)*z)+3*cos(6*atan(z/x)))
    *((cos(-pi*y/2)*x-sin(-pi*y/2)*z)+3*cos(6*atan(z/x)))+25*y*y
    +((sin(-pi*y/2)*x+cos(-pi*y/2)*z)+3*sin(6*atan(z/x)))
    *((sin(-pi*y/2)*x+cos(-pi*y/2)*z)+3*sin(6*atan(z/x)))-25
    }
  threshold 0
  contained_by { box {<-10, -4, -10>, <10, 4, 10>} }
  max_gradient 500
  texture {
    pigment{ color rgbt <0.85,0.9,1,0.4> }
    finish {
      ambient 0.5
      reflection 0.5
      diffuse 0.3
      phong 0.3
      specular 1
      brilliance 1.5
      }
    }
  rotate x*-12
  no_shadow
  }

camera {
  location <100, 100, -40>
  angle 6.5
  look_at <0, -0.2, 0>
  }

light_source { <-1000, 1000, 500> color rgb <0.5, 0.8, 1> }