/** @return */ public WB_Plane getPlane() { WB_Coord fn = getFaceNormal(); if (WB_Vector.getSqLength3D(fn) < 0.5) { if (WB_Epsilon.isEqualAbs(_halfedge.getVertex().xd(), _halfedge.getEndVertex().xd())) { fn = new WB_Vector(1, 0, 0); } else { fn = new WB_Vector(0, 0, 1); } } return new WB_Plane(getFaceCenter(), fn); }