int main ()
{
// Construct P - a bounded rectangle that contains a rectangular hole.
Polygon_2 outP;
Polygon_2 holesP[1];
outP.push_back (Point_2 (-3, -5)); outP.push_back (Point_2 (3, -5));
outP.push_back (Point_2 (3, 5)); outP.push_back (Point_2 (-3, 5));
holesP[0].push_back (Point_2 (-1, -3));
holesP[0].push_back (Point_2 (-1, 3));
holesP[0].push_back (Point_2 (1, 3));
holesP[0].push_back (Point_2 (1, -3));
Polygon_with_holes_2 P (outP, holesP, holesP + 1);
std::cout << "P = "; print_polygon_with_holes (P);
// Construct Q - a bounded rectangle that contains a rectangular hole.
Polygon_2 outQ;
Polygon_2 holesQ[1];
outQ.push_back (Point_2 (-5, -3)); outQ.push_back (Point_2 (5, -3));
outQ.push_back (Point_2 (5, 3)); outQ.push_back (Point_2 (-5, 3));
holesQ[0].push_back (Point_2 (-3, -1));
holesQ[0].push_back (Point_2 (-3, 1));
holesQ[0].push_back (Point_2 (3, 1));
holesQ[0].push_back (Point_2 (3, -1));
Polygon_with_holes_2 Q (outQ, holesQ, holesQ + 1);
std::cout << "Q = "; print_polygon_with_holes (Q);
// Compute the symmetric difference of P and Q.
Pwh_list_2 symmR;
Pwh_list_2::const_iterator it;
CGAL::symmetric_difference (P, Q, std::back_inserter(symmR));
std::cout << "The symmetric difference:" << std::endl;
for (it = symmR.begin(); it != symmR.end(); ++it) {
std::cout << "--> ";
print_polygon_with_holes (*it);
}
return 0;
}
Polygon_2 CPElement::intersection_with_support(const Polygon_2& P) const
{
static log4cplus::Logger logger = Logger("intersection_with_support");
typedef std::list<Bso_polygon_with_holes_2> Pwh_list_2;
Pwh_list_2 intR;
Pwh_list_2::const_iterator it;
CGAL::intersection(change_kernel<Bso_kernel>(P), change_kernel<Bso_kernel>(support()), std::back_inserter(intR));
if (intR.size() > 1) {
LOG4CPLUS_WARN(logger, "intersection yielded more than one component");
}
Polygon_with_holes_2 pwh = to_common(*intR.begin());
if (pwh.holes_begin() != pwh.holes_end()) {
LOG4CPLUS_WARN(logger, "intersection yielded holes");
}
return pwh.outer_boundary();
}