void
arrangement::compute_neighbours()
{
neighbours.resize(nonCriticalRegions.number_of_faces() - 1); // minus unbounded face
for (Arrangement_2::Face_iterator face = nonCriticalRegions.faces_begin(); face != nonCriticalRegions.faces_end(); ++face)
{
if (!face->is_unbounded() && face->data() != -1)
{
Arrangement_2::Ccb_halfedge_circulator first_outer_ccb = face->outer_ccb();
Arrangement_2::Ccb_halfedge_circulator outer_ccb = face->outer_ccb();
int id_face = face->data();
std::vector<int> voisins;
do
{
Arrangement_2::Face_handle adjacent_face = outer_ccb->twin()->face();
if (!adjacent_face->is_unbounded())
voisins.push_back(adjacent_face->data());
++outer_ccb;
} while (outer_ccb != first_outer_ccb);
neighbours[id_face] = voisins;
}
}
// clean neighbours
for (int i = 0; i < (int) neighbours.size(); ++i)
for (int j = 0; j < (int) neighbours[i].size(); ++j)
for (int k = 0; k < j; ++k)
if (neighbours[i][j] == neighbours[i][k])
{
neighbours[i].erase(neighbours[i].begin() + j);
--j;
break;
}
// print results
print_neighbours();
}
int main ()
{
Arrangement_2 arr;
// Construct an arrangement of seven intersecting line segments.
insert (arr, Segment_2 (Point_2 (1, 1), Point_2 (7, 1)));
insert (arr, Segment_2 (Point_2 (1, 1), Point_2 (3, 7)));
insert (arr, Segment_2 (Point_2 (1, 4), Point_2 (7, 1)));
insert (arr, Segment_2 (Point_2 (2, 2), Point_2 (9, 3)));
insert (arr, Segment_2 (Point_2 (2, 2), Point_2 (4, 4)));
insert (arr, Segment_2 (Point_2 (7, 1), Point_2 (9, 3)));
insert (arr, Segment_2 (Point_2 (3, 7), Point_2 (9, 3)));
// Create a mapping of the arrangement faces to indices.
CGAL::Arr_face_index_map<Arrangement_2> index_map (arr);
// Perform breadth-first search from the unbounded face, and use the BFS
// visitor to associate each arrangement face with its discover time.
Discover_time_bfs_visitor<CGAL::Arr_face_index_map<Arrangement_2> >
bfs_visitor (index_map);
Arrangement_2::Face_handle uf = arr.unbounded_face();
boost::breadth_first_search (Dual_arrangement_2 (arr), uf,
boost::vertex_index_map (index_map).
visitor (bfs_visitor));
// Print the results:
Arrangement_2::Face_iterator fit;
for (fit = arr.faces_begin(); fit != arr.faces_end(); ++fit)
{
std::cout << "Discover time " << fit->data() << " for ";
if (fit != uf)
{
std::cout << "face ";
print_ccb<Arrangement_2> (fit->outer_ccb());
}
else
std::cout << "the unbounded face." << std::endl;
}
return (0);
}
GeometryPtr
Overlay::process(const Polyline2DPtr& p1, const Polyline2DPtr& p2)
{
if (!p1 || !p2 || p1->getPointListSize() < 2 || p2->getPointListSize() < 2) return GeometryPtr();
#ifdef WITH_CGAL
// Construct the first arrangement, containing a polyline 1.
Arrangement_2 arr1;
for (Point2Array::const_iterator it1 = p1->getPointList()->begin()+1; it1 != p1->getPointList()->end(); ++it1)
insert_non_intersecting_curve(arr1,toSegment(*(it1-1),*it1));
// to be a closed face, first and last point should be exactly the same.
// However we should not duplicate the same point twice at the end.
Vector2& fp1 = p1->getPointList()->getAt(0);
Vector2& lp1 = *(p1->getPointList()->end()-1);
if (fp1.x() != lp1.x() || fp1.y() != lp1.y())
insert_non_intersecting_curve(arr1,toSegment(lp1,fp1));
// std::cerr << arr1.number_of_vertices() << " " << arr1.number_of_edges() << " " << arr1.number_of_faces() << std::endl;
// Mark just the bounded face.
Arrangement_2::Face_iterator fit;
CGAL_assertion (arr1.number_of_faces() == 2);
for (fit = arr1.faces_begin(); fit != arr1.faces_end(); ++fit)
fit->set_data (fit != arr1.unbounded_face());
// Construct the second arrangement.
Arrangement_2 arr2;
for (Point2Array::const_iterator it2 = p2->getPointList()->begin()+1; it2 != p2->getPointList()->end(); ++it2)
insert(arr2,toSegment(*(it2-1),*it2));
// to be a closed face, first and last point should be exactly the same.
// However we should not duplicate the same point twice at the end.
Vector2& fp2 = p2->getPointList()->getAt(0);
Vector2& lp2 = *(p2->getPointList()->end()-1);
if (fp2.x() != lp2.x() || fp2.y() != lp2.y())
insert(arr2,toSegment(lp2,fp2));
// std::cerr << arr2.number_of_vertices() << " " << arr2.number_of_edges() << " " << arr2.number_of_faces() << std::endl;
CGAL_assertion (arr2.number_of_faces() == 2);
for (fit = arr2.faces_begin(); fit != arr2.faces_end(); ++fit)
fit->set_data (fit != arr2.unbounded_face());
// Compute the overlay of the two arrangements.
Arrangement_2 overlay_arr;
Overlay_traits overlay_traits;
overlay (arr1, arr2, overlay_arr, overlay_traits);
// std::cerr << overlay_arr.number_of_vertices() << " " << overlay_arr.number_of_edges() << " " << overlay_arr.number_of_faces() << std::endl;
// conversion between cgal structures and plantgl ones.
GeometryArrayPtr geomarray(new GeometryArray(0));
for (Arrangement_2::Face_iterator face = overlay_arr.faces_begin(); face != overlay_arr.faces_end(); ++face)
{
if (face->is_fictitious () || face->is_unbounded())
continue;
if (! face->data())
continue;
Arrangement_2::Ccb_halfedge_circulator curr = face->outer_ccb();
Point2ArrayPtr pointSet( new Point2Array(1,toVec2(curr->source()->point())));
do
{
pointSet->push_back(toVec2(curr->target()->point()));
++curr;
} while (curr != face->outer_ccb());
if (pointSet->size() == 1){
geomarray->push_back(GeometryPtr(new PointSet2D(pointSet)));
}
else if(pointSet->size() > 1){
geomarray->push_back(GeometryPtr(new Polyline2D(pointSet)));
}
}
if (geomarray->empty())return GeometryPtr();
else if (geomarray->size() == 1) return geomarray->getAt(0);
else return GeometryPtr(new Group(geomarray));
#else
#ifdef _MSC_VER
#pragma message("CGAL not included. Overlay routine will not work.")
#else
#warning "CGAL not included. Overlay routine will not work."
#endif
pglError("CGAL not included. Overlay routine will not work.");
return GeometryPtr();
#endif
}