// SUNKEN / Marble '05.06
// By Tsutomu HIGO  URL: http://www.asahi-net.or.jp/~nj2t-hg/

#version 3.6;
global_settings {
  max_trace_level 4
  assumed_gamma 2.2
  }

camera {
  location <10, 50, -200>
  look_at <1, -7, 0>
  angle 60
  }

#declare fn_Pigm = function {
  pigment {
    gradient x
    pigment_map { [0.5 marble turbulence 0.6] }
    rotate y*45 
    scale 6
    }
  }

isosurface {
  function { (y+200*fn_Pigm(x, y, z).gray*0.6/(x*x+z*z+30))*(y+5) }
  threshold 5
  max_gradient 100
  contained_by {box {<-30, -3, -30>, <30, 10, 30>}}
  texture {
    pigment {color rgb <0.4, 0.4, 0.4>}
    finish {
      ambient 0.0001
      diffuse 1
      reflection 0.5
      specular 1
      phong 0.5
      brilliance 1
      }
    }
  scale y*3  scale 7
  no_shadow
  }

background { color rgb <0.3, 0.5, 1> }

fog {
  color rgb <0.8, 0.9, 1>
  fog_type 2
  fog_alt 0.45
  fog_offset 60
  distance 100
  turbulence <.2, .2, .2>
  omega 0.40
  lambda 1.25
  octaves 50
  }