File:Blue Square Knot Animated.gif

#include "colors.inc"

background { color White }

global_settings { assumed_gamma 1.0}

camera
  {
  location <0, 0, -25>
  right <1,0,0> up <0,13/18,0>
  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 71,
  <-0.381811,0.463006,-0.123497>, r_tube
  <-0.478758,0.36928,-0.051525>, r_tube
  <-0.552347,0.262152,0.0429328>, r_tube
  <-0.621253,0.148386,0.136898>, r_tube
  <-0.692522,0.0220062,0.193317>, r_tube
  <-0.750052,-0.116355,0.189675>, r_tube
  <-0.774886,-0.248191,0.127645>, r_tube
  <-0.757884,-0.350889,0.0237938>, r_tube
  <-0.700242,-0.407758,-0.0985641>, r_tube
  <-0.610847,-0.410894,-0.214748>, r_tube
  <-0.503817,-0.361675,-0.302175>, r_tube
  <-0.396028,-0.270564,-0.343322>, r_tube
  <-0.303919,-0.155828,-0.328894>, r_tube
  <-0.239133,-0.0396016,-0.260466>, r_tube
  <-0.204539,0.0607906,-0.150539>, r_tube
  <-0.196692,0.14428,-0.0186328>, r_tube
  <-0.216352,0.225336,0.113639>, r_tube
  <-0.272194,0.313775,0.225253>, r_tube
  <-0.369014,0.401666,0.297844>, r_tube
  <-0.497419,0.471303,0.319711>, r_tube
  <-0.636694,0.506741,0.289238>, r_tube
  <-0.762736,0.499133,0.21472>, r_tube
  <-0.853805,0.447791,0.111994>, r_tube
  <-0.89408,0.359577,0.00192659>, r_tube
  <-0.876347,0.247836,-0.0920953>, r_tube
  <-0.804727,0.130541,-0.147502>, r_tube
  <-0.696277,0.0251563,-0.148387>, r_tube
  <-0.575452,-0.06265,-0.0955125>, r_tube
  <-0.456877,-0.14133,-0.0154265>, r_tube
  <-0.335348,-0.211741,0.0574875>, r_tube
  <-0.202022,-0.262703,0.10807>, r_tube
  <-0.0582469,-0.287242,0.136195>, r_tube
  <0.0895219,-0.283825,0.14303>, r_tube
  <0.234225,-0.252381,0.126956>, r_tube
  <0.369169,-0.195147,0.0842625>, r_tube
  <0.494114,-0.121136,0.0160594>, r_tube
  <0.617583,-0.0403047,-0.0554485>, r_tube
  <0.738731,0.0526625,-0.0924469>, r_tube
  <0.837028,0.165163,-0.074236>, r_tube
  <0.888483,0.286508,-0.00667971>, r_tube
  <0.880566,0.396561,0.0909141>, r_tube
  <0.81457,0.476802,0.194991>, r_tube
  <0.702858,0.514686,0.282755>, r_tube
  <0.565622,0.505405,0.335208>, r_tube
  <0.427612,0.452895,0.339609>, r_tube
  <0.313509,0.369913,0.292008>, r_tube
  <0.240511,0.275398,0.1989>, r_tube
  <0.21098,0.185652,0.0756985>, r_tube
  <0.215325,0.101009,-0.0572063>, r_tube
  <0.246192,0.00662187,-0.177145>, r_tube
  <0.304425,-0.105569,-0.261534>, r_tube
  <0.3897,-0.224003,-0.293245>, r_tube
  <0.49313,-0.326364,-0.266316>, r_tube
  <0.599245,-0.391403,-0.187411>, r_tube
  <0.690947,-0.405227,-0.0732515>, r_tube
  <0.753441,-0.363503,0.0531281>, r_tube
  <0.776855,-0.271844,0.165867>, r_tube
  <0.758686,-0.145366,0.23992>, r_tube
  <0.706261,-0.006625,0.256064>, r_tube
  <0.637298,0.122258,0.208252>, r_tube
  <0.570923,0.235573,0.113105>, r_tube
  <0.505406,0.341506,0.00770625>, r_tube
  <0.420286,0.438144,-0.0789328>, r_tube
  <0.306633,0.513772,-0.140006>, r_tube
  <0.172308,0.561683,-0.177497>, r_tube
  <0.0278437,0.580766,-0.194372>, r_tube
  <-0.118434,0.571147,-0.192094>, r_tube
  <-0.258427,0.531941,-0.169481>, r_tube
  <-0.381811,0.463006,-0.123497>, r_tube
  <-0.478758,0.36928,-0.051525>, r_tube
  <-0.552347,0.262152,0.0429328>, 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
    }
  rotate <0,360*clock,0>
  }

plane
  {
  <0,0,-1>, -2.33
  pigment { color White }
  finish
    {
    ambient 0.35
    diffuse 0.65
    }
  }