getHoles
Gets this polygon's hole indices, with each hole represented as a single offset into this polygon's positions array. Each hole implicitly continues along an internal linear ring from that vertex offset until reaching either the end of the positions array, or the next hole offset.
If 'result' argument is given, hole indices are written to that array and returned. Otherwise, returns an ArrayView on collection memory — changes to this array will not trigger render updates, which requires .setHoles().