Function canonicalize_like

src/svgfill/src/arrange_polygons.cpp:982–984

}

DDir canonicalize_like(const DDir& a, const DDir& ref) {
    return (a * ref) < 0. ? -a : a;
}

DPoint to_double_point(const Point_2& p) {
    return {CGAL::to_double(p.x()), CGAL::to_double(p.y())};