bool join(PointContour& c1, PointContour& c2) {
ContourPoint c1_front = c1.front();
ContourPoint c1_back = c1.back();
ContourPoint c2_front = c2.front();
ContourPoint c2_back = c2.back();
if (c1_back == c2_front) {
c1.splice(c1.end(), c2);
}
else if (c1_front == c2_back) {
c1.splice(c1.begin(), c2);
}
else if (c1_back == c2_back) {
if (c2.size() < c1.size()) {
c2.reverse();
c1.splice(c1.end(), c2);
}
else {
c1.reverse();
c1.splice(c1.begin(), c2);
}
}
else if (c1_front == c2_front) {
if (c2.size() < c1.size()) {
c2.reverse();
c1.splice(c1.begin(), c2);
}
else {
c1.reverse();
c1.splice(c1.end(), c2);
}
}
else
return false;
return true;
}
inline bool closed(PointContour& c) {
return c.front() == c.back();
}