/* make pictures of top                                                */ 
/* originally for http://www.dynamical-systems.org/, logo              */
/* last update 2021 for https://www.youtube.com/watch?v=Tqn6d0lohUg    */

#include "finish.inc"
camera        { location<0,0.7,-4> up y right x look_at <0,-0.7,4>  }
light_source  { <-500,0,-1000> color rgb <1,1,1>                    }
light_source  { < 0, 10, 0>    color rgb <1,1,1> area_light <-6,0,-6>, <6,0,6>, 5, 5 adaptive 1 jitter fade_distance 20 fade_power 2     }
light_source  { < 0, 0, -10>   color rgb <0.3,0.3,0.3> area_light <-6,-6,-6>, <6,6,0>, 5, 5 adaptive 1 jitter fade_distance 20 fade_power 2     }
background { rgb<1,1,1> }

#declare r=1.0;                                 // radius of main torus
#declare s=0.05;                                // size of metal parts 
#declare phi = 20;                              // rotation around y axes
#declare psi = 360*clock;                       // rotation around z axes

#declare Top = union{ 
  cylinder   { <0,-0.9,0>,<0,0.9,0>,s } 
  cylinder   { <0,-1.0,0>,<0,-1.2,0>,s } 
  cylinder   { <0, 1.0,0>,<0, 1.2,0>,s } 
  difference { sphere { <0,0,0>,2*s scale <1,0.8,1> translate <0,-1.2,0>} cylinder { <-5,-1.25,-0>,< 5,-1.25,0>, 0.03 } }
  difference { sphere { <0,0,0>,2*s scale <1,0.8,1> translate <0, 1.2,0>} cylinder { <-5, 1.25,-0>,<5, 1.25,0>, 0.03 } }
  cylinder   { <0,-1.0,0>,<0,1.0,0>,s/2 } 
  sphere     { <0,0,0>,2*s scale <1,0.5,1> pigment { rgb <1,0,0> } finish  { ambient .1 diffuse .6 reflection .55 specular 1 metallic } }
  torus      { 1.05*r,s }
  torus      { 0.8*r,2*s scale <1,0.6,1> pigment { rgb<0.98,0.98,0.94>} texture{ pigment {rgb <0,0,1>}  finish { Phong_Shiny   } } }
  torus      { r,s  rotate x*90 } 
  cylinder   { <0,-0.02,0>,<0,0.02,0>, 0.8*r texture{ pigment {rgb <1,1,0>}  finish {Phong_Shiny   } } } 
 texture { pigment {rgb <1,0.5,0>}  finish {Phong_Shiny   } }
}

#declare MyPlane=plane{ <0,0,1>, 3.0 pigment{colour rgb<1.0,1.0,1.0>} finish{ambient 0.2 diffuse 0.8} }
#declare Wire = cylinder { <-10,-1.28,0>,<10,-1.28,0>,0.02 texture{ pigment {rgb <0.5,0.5,1.0>}  finish {Phong_Shiny   } } }
#declare M=<0,-1.30,0>;
 
#object { MyPlane }
#object { Top  rotate y*30 translate -M rotate -y*psi  rotate z*phi rotate y*psi translate M } 
#object { Wire    }