int main()
{
Arrangement_2 arr;
// Construct an arrangement of five linear objects.
std::vector<X_monotone_curve_2> curves;
curves.push_back(Ray_2(Point_2(0, 0), Point_2(0, 1)));
curves.push_back(Ray_2(Point_2(0, 0), Point_2(1, 0)));
curves.push_back(Ray_2(Point_2(0, 0), Point_2(0, -1)));
curves.push_back(Ray_2(Point_2(0, 0), Point_2(-1, 0)));
curves.push_back(Ray_2(Point_2(0, 0), Point_2(1, 1)));
curves.push_back(Ray_2(Point_2(0, 0), Point_2(1, -1)));
curves.push_back(Ray_2(Point_2(0, 0), Point_2(-1, 1)));
curves.push_back(Ray_2(Point_2(0, 0), Point_2(-1, -1)));
std::vector<Halfedge_handle> hhs(curves.size());
for (size_t i = 0; i < curves.size(); i++)
hhs[i] = insert_non_intersecting_curve(arr, curves[i]);
bool valid = arr.is_valid();
std::cout << "Arrangement size:"
<< " V = " << arr.number_of_vertices()
<< ", E = " << arr.number_of_edges()
<< ", F = " << arr.number_of_faces() << std::endl;
std::cout << "The arrangement is "
<< (valid ? "valid." : "NOT valid!") << std::endl;
if (! valid) return (1);
// Remove the edges.
for (size_t i = 0; i < hhs.size(); i++) {
arr.remove_edge(hhs[i]);
bool valid = arr.is_valid();
std::cout << " Removed " << i+1 << " curve(s), arrangement is "
<< (valid ? "valid." : "NOT valid!") << std::endl;
if (! valid) return (1);
}
std::cout << "Final arrangement size:"
<< " V = " << arr.number_of_vertices()
<< ", E = " << arr.number_of_edges()
<< ", F = " << arr.number_of_faces() << std::endl;
if (!::test(arr)) return 1;
/* Construct another arrangement of a segment connected to a ray.
* First remove the ray, then remove the segment.
*
* o---------------o
* | |
* | |
* | |
* | o--o----|
* | |
* | |
* | |
* o---------------o
*/
if (!test_ray(arr, arr.unbounded_face())) return 1;
/* Construct another arrangement of a segment connected to a ray.
* First remove the ray, then remove the segment.
*
* o---------------o
* | |
* | |
* | |
* | o--o----|
* | |
* o---------------o
* | |
* o---------------o
*/
Line_2 l1(Point_2(0, -1), Point_2(1, -1));
Halfedge_handle eh1 =
arr.insert_in_face_interior(X_monotone_curve_2(l1), arr.unbounded_face());
if (!test_ray(arr, eh1->face())) return 1;
arr.remove_edge(eh1);
/* Construct another arrangement of a segment connected to a ray.
* First remove the ray, then remove the segment.
*
* o-----o---------o
* | | |
* | | |
* | | |
* | | o--o----|
* | | |
* | | |
* | | |
* o-----o---------o
*/
Line_2 l2(Point_2(-1, 0), Point_2(-1, 1));
Halfedge_handle eh2 =
arr.insert_in_face_interior(X_monotone_curve_2(l2), arr.unbounded_face());
if (!test_ray(arr, eh2->twin()->face())) return 1;
arr.remove_edge(eh2);
return 0;
}
int main ()
{
// Construct the initial arrangement.
Arrangement_2 arr;
Segment_2 segs[N_SEGMENTS];
Halfedge_handle hhs[N_SEGMENTS];
bool valid;
int k;
segs[0] = Segment_2 (Point_2 (5, 9), Point_2 (5, 11));
segs[1] = Segment_2 (Point_2 (5, 9), Point_2 (7, 9));
segs[2] = Segment_2 (Point_2 (5, 11), Point_2 (7, 9));
segs[3] = Segment_2 (Point_2 (7, 6), Point_2 (9, 7));
segs[4] = Segment_2 (Point_2 (9, 7), Point_2 (7, 9));
segs[5] = Segment_2 (Point_2 (5, 9), Point_2 (7, 6));
segs[6] = Segment_2 (Point_2 (10, 11), Point_2 (8, 13));
segs[7] = Segment_2 (Point_2 (8, 13), Point_2 (11, 12));
segs[8] = Segment_2 (Point_2 (10, 11), Point_2 (11, 12));
segs[9] = Segment_2 (Point_2 (1, 20), Point_2 (5, 1));
segs[10] = Segment_2 (Point_2 (5, 1), Point_2 (12, 6));
segs[11] = Segment_2 (Point_2 (1, 20), Point_2 (12, 6));
segs[12] = Segment_2 (Point_2 (13, 13), Point_2 (13, 15));
segs[13] = Segment_2 (Point_2 (13, 15), Point_2 (15, 12));
segs[14] = Segment_2 (Point_2 (13, 13), Point_2 (15, 12));
segs[15] = Segment_2 (Point_2 (11, 12), Point_2 (13, 13));
segs[16] = Segment_2 (Point_2 (1, 20), Point_2 (11, 17));
segs[17] = Segment_2 (Point_2 (11, 17), Point_2 (20, 13));
segs[18] = Segment_2 (Point_2 (12, 6), Point_2 (20, 13));
segs[19] = Segment_2 (Point_2 (15, 12), Point_2 (20, 13));
segs[20] = Segment_2 (Point_2 (5, 1), Point_2 (20, 1));
segs[21] = Segment_2 (Point_2 (20, 1), Point_2 (20, 13));
segs[22] = Segment_2 (Point_2 (15, 5), Point_2 (17, 3));
segs[23] = Segment_2 (Point_2 (13, 3), Point_2 (17, 3));
segs[24] = Segment_2 (Point_2 (12, 6), Point_2 (13, 3));
segs[25] = Segment_2 (Point_2 (17, 3), Point_2 (20, 1));
for (k = 0; k < N_SEGMENTS; k++)
{
hhs[k] = insert_non_intersecting_curve (arr, segs[k]);
}
valid = arr.is_valid();
std::cout << "Arrangement size:"
<< " V = " << arr.number_of_vertices()
<< ", E = " << arr.number_of_edges()
<< ", F = " << arr.number_of_faces() << std::endl;
std::cout << "The arrangement is "
<< (valid ? "valid." : "NOT valid!") << std::endl;
if (! valid)
return (1);
// Remove some edges.
int del_indices[N_REMOVE] = {25, 23, 22, 1, 3, 11, 19, 15, 4, 24};
for (k = 0; k < N_REMOVE; k++)
{
arr.remove_edge (hhs[del_indices[k]]);
valid = arr.is_valid();
std::cout << " Removed " << k+1 << " segment(s), arrangement is "
<< (valid ? "valid." : "NOT valid!") << std::endl;
if (! valid)
return (1);
}
std::cout << "Final arrangement size:"
<< " V = " << arr.number_of_vertices()
<< ", E = " << arr.number_of_edges()
<< ", F = " << arr.number_of_faces() << std::endl;
// Check the validity more thoroughly.
valid = is_valid(arr);
std::cout << "Arrangement is "
<< (valid ? "valid." : "NOT valid!") << std::endl;
return (0);
}