how to convert polygons to bezier curve?

[srxqds]

I want to do svg bezier curve boolean operator, but using clipper1 it will convert the curve to polygons, how can I convert polygons to the bezier curve after the boolean operator?

[AngusJohnson]

The short answer is you can't, at least not without a lot of work. And it's not simple.

Edit: more info here.