@gilboonet Well, actually I figured out! I was using earcut.js to create indice, and with little bit of touch with the result of CAG union/subtract/intersect it worked well. Thanks for the reply.

I am trying to union/subtract/intersect two simple polygons.
I've found how to do it from CAG.
But I would like to get points as counter clock wise.
The result using CAG functionality, I could get counter clock wise direction line drawing points, but what I like to get is counter clock wise points order.
Is there anyway that I can get it?
It would be fine also if I can use CSG functioinality.

Thank you.