How to get outer wire?

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su tianxiao's picture

Hi all,
I have some wires to be treated,they are all on the same plane and are all closed.
First I use the BRepBuilderAPI_MakeFace(aWire) to make a face and use the BRepTools::OuterWire to get the wire.It does work, because in some case, the face is not the biggest face of the wire,it can't contain the wire ,and maybe have some hole.
So what can I get the outer wire?
Thanks!