Double Fishblobs

The Construction in Details:

How to calculate the radius Ri of the inner circles:

The radius of the inner circles here is called Ri.
Look at the opposite image:
Ri (orange) = 1/2*Ra.
If the center of the outer circle is at
M₀ = <0,0,0>, we have the centers
of the inner circles at
M₁ = <Ri,0,0> and M₁ = <-Ri,0,0> .
As a torus segment we use here my macro "#macro Torus_Segment( R_major, R_minor, Segment_Angle)" from my inlude file. This file must be included to our text by #include "shapes_lo.inc" !

How to define the radius Ri of the inner circles?
The orange segment of a torus must be rotated by 180 degrees.

// center:
#declare M  = <0,0,0>;
// outer radius:
#declare Ra = 3.00 -R0;
// radius of inner half circles:
#declare Ri  = Ra /2 ;

//  2 torus segments
#include "shapes_lo.inc"

union{   //-----------------------
torus { Ra,  R0
          rotate<90,0,0>
         translate M0
  } // end of torus  -------------
object{
  Torus_Segment( Ri, R0, 180)
   rotate<-90,0,0>
   translate < Ri,0,0>
 } // end of Torus_Segment(...) --
object{
   Torus_Segment( Ri, R0, 180)
   rotate<-90,0,0> rotate<0,0,180>
   translate <-Ri,0,0>
 } // end of Torus_Segment(...) --
}// end of union
//------------------------- end

Click here for the complete scene file for POV-Ray:
".txt" file or ".pov" file