This image was created with POV-Ray.

I, the copyright holder of this work, release this work into the public domain. This applies worldwide. In some countries this may not be legally possible; if so: I grant anyone the right to use this work for any purpose, without any conditions, unless such conditions are required by law.

This image was created using POV-Ray for Windows, version 3.6. The image was rendered to an 1800 x 1800 square, using 0.3 anti-aliasing, and then cropped and compressed using pngcrush.

#include "colors.inc"  background { color White }  global_settings { assumed_gamma 1.0}  camera   {   location <0, 0, -25>   right <1,0,0> up <0,1,0>   look_at  <0, 0, 0>   angle 5   }  light_source   {   <0, 20, -50>   color White   area_light <5, 0, 0>, <0, 5, 0>, 10, 10  /* very slow, decrease 10 to 2 for experiments */   adaptive 3   }   #declare r_tube = 0.07;  // thickness (radius) of tube  sphere_sweep   {   cubic_spline 88,   <-0.703555,0.146282,0.048166>, r_tube   <-0.725187,0.0490296,0.107044>, r_tube   <-0.72638,-0.0551355,0.157324>, r_tube   <-0.703477,-0.162582,0.193416>, r_tube   <-0.654001,-0.265826,0.209899>, r_tube   <-0.578756,-0.353546,0.202624>, r_tube   <-0.483734,-0.412334,0.17037>, r_tube   <-0.380529,-0.43071,0.116382>, r_tube   <-0.282952,-0.404047,0.0490348>, r_tube   <-0.200393,-0.334936,-0.0140192>, r_tube   <-0.132761,-0.235025,-0.0440029>, r_tube   <-0.0741813,-0.128357,-0.0226823>, r_tube   <-0.017015,-0.0313637,0.0333297>, r_tube   <0.0477639,0.0629969,0.0824164>, r_tube   <0.119974,0.160781,0.0899901>, r_tube   <0.186607,0.253806,0.0487884>, r_tube   <0.235564,0.339737,-0.0239663>, r_tube   <0.262656,0.43009,-0.101429>, r_tube   <0.265808,0.533944,-0.161344>, r_tube   <0.242049,0.646253,-0.190913>, r_tube   <0.191224,0.752571,-0.1857>, r_tube   <0.118016,0.83679,-0.147999>, r_tube   <0.031112,0.885721,-0.0853214>, r_tube   <-0.058528,0.891324,-0.00896143>, r_tube   <-0.139375,0.851795,0.0674505>, r_tube   <-0.201068,0.772193,0.129571>, r_tube   <-0.236368,0.664267,0.164353>, r_tube   <-0.242983,0.544968,0.162563>, r_tube   <-0.224411,0.432943,0.121582>, r_tube   <-0.187515,0.342305,0.0477639>, r_tube   <-0.13542,0.2744,-0.0428877>, r_tube   <-0.0638971,0.21595,-0.126808>, r_tube   <0.0286869,0.15322,-0.178839>, r_tube   <0.131127,0.0858478,-0.181537>, r_tube   <0.224398,0.0217303,-0.133423>, r_tube   <0.295571,-0.0371089,-0.0499297>, r_tube   <0.345034,-0.101188,0.0450275>, r_tube   <0.376314,-0.183448,0.130505>, r_tube   <0.386196,-0.285901,0.193364>, r_tube   <0.369765,-0.399274,0.226979>, r_tube   <0.326813,-0.509911,0.229962>, r_tube   <0.262085,-0.605828,0.205373>, r_tube   <0.182639,-0.679723,0.159127>, r_tube   <0.0950869,-0.728992,0.097953>, r_tube   <0.00409813,-0.753697,0.0281163>, r_tube   <-0.0875521,-0.754177,-0.0447551>, r_tube   <-0.177866,-0.729757,-0.114916>, r_tube   <-0.264096,-0.679321,-0.175519>, r_tube   <-0.341662,-0.603247,-0.21842>, r_tube   <-0.404067,-0.505813,-0.235175>, r_tube   <-0.44405,-0.396758,-0.219146>, r_tube   <-0.455878,-0.290881,-0.168088>, r_tube   <-0.437773,-0.205054,-0.0860606>, r_tube   <-0.392421,-0.153465,0.0160034>, r_tube   <-0.322637,-0.144179,0.118872>, r_tube   <-0.230195,-0.175019,0.195452>, r_tube   <-0.123774,-0.230577,0.221338>, r_tube   <-0.0206074,-0.288677,0.18889>, r_tube   <0.0669188,-0.333108,0.111713>, r_tube   <0.145704,-0.360459,0.0168723>, r_tube   <0.232413,-0.371171,-0.0707056>, r_tube   <0.332285,-0.360212,-0.137248>, r_tube   <0.437267,-0.322681,-0.177438>, r_tube   <0.535506,-0.259795,-0.19077>, r_tube   <0.617494,-0.177405,-0.180188>, r_tube   <0.677967,-0.0826811,-0.150541>, r_tube   <0.715265,0.0180213,-0.107109>, r_tube   <0.729726,0.119982,-0.0547411>, r_tube   <0.722178,0.219854,0.00238625>, r_tube   <0.693011,0.314993,0.0603436>, r_tube   <0.642148,0.402765,0.11476>, r_tube   <0.569782,0.479916,0.160281>, r_tube   <0.477691,0.542439,0.190355>, r_tube   <0.370867,0.58613,0.197955>, r_tube   <0.258338,0.608112,0.177322>, r_tube   <0.151229,0.609604,0.12651>, r_tube   <0.0558434,0.598814,0.0499816>, r_tube   <-0.0340429,0.587544,-0.0382059>, r_tube   <-0.13127,0.576948,-0.116044>, r_tube   <-0.239442,0.555848,-0.165585>, r_tube   <-0.349949,0.516748,-0.180966>, r_tube   <-0.451896,0.461163,-0.165637>, r_tube   <-0.53902,0.393804,-0.127379>, r_tube   <-0.609739,0.318248,-0.0744925>, r_tube   <-0.664558,0.235831,-0.0140581>, r_tube   <-0.703555,0.146282,0.048166>, r_tube   <-0.725187,0.0490296,0.107044>, r_tube   <-0.72638,-0.0551355,0.157324>, r_tube   pigment { color rgb <0,0.25,1> }   finish               {     ambient 0.15     diffuse 0.85     brilliance 2     phong 0.25     phong_size 7.5     }   }  plane   {   <0,0,-1>, -0.33   pigment { color White }   finish     {     ambient 0.35     diffuse 0.65     }   }