/**
* intersection post processing
*/
void post_intersection( const GeometrySet<2>& input, GeometrySet<2>& output )
{
//
// reverse orientation of polygons if needed
for ( GeometrySet<2>::SurfaceCollection::const_iterator it = input.surfaces().begin();
it != input.surfaces().end();
++it ) {
const CGAL::Polygon_with_holes_2<Kernel>& p = it->primitive();
CGAL::Polygon_2<Kernel> outer = p.outer_boundary();
if ( outer.orientation() == CGAL::CLOCKWISE ) {
outer.reverse_orientation();
}
std::list<CGAL::Polygon_2<Kernel> > rings;
for ( CGAL::Polygon_with_holes_2<Kernel>::Hole_const_iterator hit = p.holes_begin();
hit != p.holes_end();
++hit ) {
rings.push_back( *hit );
if ( hit->orientation() == CGAL::COUNTERCLOCKWISE ) {
rings.back().reverse_orientation();
}
}
output.surfaces().push_back( CGAL::Polygon_with_holes_2<Kernel>( outer, rings.begin(), rings.end() ) );
}
output.points() = input.points();
output.segments() = input.segments();
output.volumes() = input.volumes();
}
CGAL::Polygon_with_holes_2<Kernel> Polygon::toPolygon_with_holes_2( bool fixOrientation ) const
{
std::list<CGAL::Polygon_2<Kernel> > holes;
for ( size_t i = 0; i < numInteriorRings(); ++i ) {
// note that the orientation is fixed here to avoid double reverse for interior rings
CGAL::Polygon_2<Kernel> inner = interiorRingN( i ).toPolygon_2( false );
if ( fixOrientation && inner.orientation() == CGAL::COUNTERCLOCKWISE ) {
inner.reverse_orientation();
}
holes.push_back( inner );
}
CGAL::Polygon_2<Kernel> outer = exteriorRing().toPolygon_2( fixOrientation );
return CGAL::Polygon_with_holes_2<Kernel>( outer,
holes.begin(),
holes.end() );
}
void makeValidOrientation( CGAL::Polygon_2< Kernel >& polygon )
{
if ( polygon.orientation() != CGAL::COUNTERCLOCKWISE ) {
polygon.reverse_orientation() ;
}
}