Function edge_cmp

Geometry/Point Location.cpp:32–39

    PT l, r;
};
bool edge_cmp(edge* edge1, edge* edge2) {
    const PT a = edge1->l, b = edge1->r;
    const PT c = edge2->l, d = edge2->r;
    int val = sign(a.cross(b, c)) + sign(a.cross(b, d));
    if (val != 0) return val > 0;
    val = sign(c.cross(d, a)) + sign(c.cross(d, b));
    return val < 0;
}
enum EventType { DEL = 2, ADD = 3, GET = 1, VERT = 0 };
struct Event {
    EventType type; int pos;