Yin & Yang 3D

Construction in details step by step:

All we need for a "Yin and Yang" is an isosurface with the function "f_comma" .
(You can get this isosurface from my "Insert Menu Add-on", click there on "Isosurfaces by function.inc" and then click "Isosurface f_comma".)
Don't forget: For using built-in functions we have to include the file "functions.inc"!

#include "functions.inc"
isosurface {
  function{ f_comma( x,y,z, 1)}
  contained_by {sphere {0,1.5}}
  rotate<90,0,0>
  scale 1.2
} // end of isosurface --------- 

Now we have to dublicate this object and turn it around the z axis by 180 degrees. Moving both parts a little bit closer together and scaling them horizontally to a perfect round shape completes the action.

Scene description for POV-Ray:
"yin_yang.txt" or "yin_yang.pov"