// Frame / Cage
// Please use freely for non comercial purpose.
// All rights reserved by Tsutomu HIGO, Nov. 14, 1998

#version 3.0
global_settings { assumed_gamma 2.2 }

#include "colors.inc"

camera {
   location <0.8,1.8,-3.8>
   angle 90
   look_at <0.2, 0.2, 0>
}

light_source {<50, 100, 50> color rgb <1,1,1>}

#declare Nt = 25
#declare Pne = int(sqrt(10)*(Nt-0.5)*(Nt-0.5)/0.156/5.5/5.5)+9
#declare Pn0 = -1500
#declare Dt = 0.2/Nt
#declare Rt = pi*2/(Nt-0.5)
#declare Yt = 0.156*5.5*5.5/(Nt-0.5)/(Nt-0.5)

union {
  #declare Pn = Pn0 #while (Pn < Pne)
    cylinder {<(10-Yt*Pn*Yt*Pn)*cos(Rt*Pn)/5,Yt*Pn, (10-Yt*Pn*Yt*Pn)*sin(Rt*Pn)/5>, <(10-Yt*(Pn-1)*Yt*(Pn-1))*cos(Rt*(Pn-1))/5,Yt*(Pn-1),(10-Yt*(Pn-1)*Yt*(Pn-1))*sin(Rt*(Pn-1))/5>, Dt}
    cylinder {<(10-Yt*Pn*Yt*Pn)*cos(Rt*Pn)/5,Yt*Pn,(10-Yt*Pn*Yt*Pn)*sin(Rt*Pn)/5>,<(10-Yt*(Pn-Nt)*Yt*(Pn-Nt))*cos(Rt*(Pn-Nt))/5,Yt*(Pn-Nt),(10-Yt*(Pn-Nt)*Yt*(Pn-Nt))*sin(Rt*(Pn-Nt))/5>, Dt}
    cylinder {<(10-Yt*Pn*Yt*Pn)*cos(Rt*Pn)/5,Yt*Pn,(10-Yt*Pn*Yt*Pn)*sin(Rt*Pn)/5>,<(10-Yt*(Pn-Nt+1)*Yt*(Pn-Nt+1))*cos(Rt*(Pn-Nt+1))/5,Yt*(Pn-Nt+1),(10-Yt*(Pn-Nt+1)*Yt*(Pn-Nt+1))*sin(Rt*(Pn-Nt+1))/5>, Dt}
  #declare Pn =Pn +1  #end
    texture {
      pigment {color rgb <0.3, 0, 0.1>}
      finish {
        ambient 0
        phong 0.5
        reflection 0.3
        specular 1.0
        brilliance 1.0
        }
      }
    rotate z*-45
  }

sky_sphere {
    pigment {
      gradient y
      color_map {
        [ 0.2 color rgb <0.3,0.3,1> ]
        [ 1.00 color rgb <1,1,1> ]
        }
      scale 1.5 rotate y*0
      rotate z*-45
      }
    }

fog {
    fog_type 2
    fog_alt 10
    fog_offset 0
    distance 10
    color rgb <0.5, 0.3, 1.0>
    turbulence <0.05, 0.05, 0.05>
    omega 0.25
    lambda 2.5
    octaves 6
    rotate z*-45
    }

#declare Sphere = sphere {<0, 0, 0>, 1}

#declare Textur =
  texture {
    pigment {colour Clear}
    halo {
      linear
      max_value 1.5
      spherical_mapping
      emitting
      turbulence 0.1
      colour_map {
         [0 color rgbt <1,0,0,1>]
         [1 color rgbt <1,1,1,0>]
      }
      samples 10
    }
  }

object {Sphere hollow texture{ Textur } scale 1}