FLOW easily maps a curved polygon on the surface of a torus, to a second torus.

>>>The second skinny torus can have the same R radius, with a smaller r radius.<<<

(The second torus can be scaled, but this should be equivalent to just scaling the original torus and surface polygon.)

- Brian

The inner curved polygon is less conformal, angles are no longer preserved. But for a small offset, this should not be very noticeable.