polyhedron cgal_to_polyhedron( const Nef_polyhedron &NP ){
Polyhedron P;
polyhedron ret;
if( NP.is_simple() ){
NP.convert_to_polyhedron(P);
std::vector<double> coords;
std::vector<int> tris;
int next_id = 0;
std::map< Polyhedron::Vertex*, int > vid;
for( Polyhedron::Vertex_iterator iter=P.vertices_begin(); iter!=P.vertices_end(); iter++ ){
coords.push_back( CGAL::to_double( (*iter).point().x() ) );
coords.push_back( CGAL::to_double( (*iter).point().y() ) );
coords.push_back( CGAL::to_double( (*iter).point().z() ) );
vid[ &(*iter) ] = next_id++;
}
for( Polyhedron::Facet_iterator iter=P.facets_begin(); iter!=P.facets_end(); iter++ ){
Polyhedron::Halfedge_around_facet_circulator j = iter->facet_begin();
tris.push_back( CGAL::circulator_size(j) );
do {
tris.push_back( std::distance(P.vertices_begin(), j->vertex()) );
} while ( ++j != iter->facet_begin());
}
ret.initialize_load_from_mesh( coords, tris );
} else {
std::cout << "resulting polyhedron is not simple!" << std::endl;
}
return ret;
}
// Checks if there are two disconnected linestrings which both have the 2 coplanar facets
bool joinCreatesNoHole (Polyhedron::Halfedge_handle& heH) {
pointVector otherFacetPnts = get_facetPoints(heH); // Get points of other facet
Polyhedron::Halfedge_around_facet_circulator hafIt = heH->opposite()->facet_begin();
bool nextNotBorder = false; // starts with heH so false
bool difFound = false; // if previous was not border
bool refound = false; // if two border sections found with not border in between
bool canJoinFacets = true; // output
do {
if (difFound ^ nextNotBorder) { // heH->facet() != hafIt->opposite()->facet()) {
if (refound) {
canJoinFacets=false; //if refound twice -> discconnected borders
break;
}
refound = difFound; // Set refound true
difFound = !difFound; // Flip difFound
}
nextNotBorder = heH->facet() != hafIt->next()->opposite()->facet();
if (difFound && nextNotBorder && // if current and next are not border and point is on other facet
std::find(otherFacetPnts.begin(), otherFacetPnts.end(),hafIt->vertex()->point())!=otherFacetPnts.end()) {
canJoinFacets=false; // Point is touching
break;
}
} while (++hafIt != heH->opposite()->facet_begin());
return canJoinFacets;
}
bool triDoesNotIntersectFacet (Polyhedron::Halfedge_handle& heH, bool isOpposite) {
Segment_3 checkSeg (heH->vertex()->point(),heH->prev()->prev()->vertex()->point());
Polyhedron::Halfedge_around_facet_circulator hafIt = heH->facet_begin()++; // skip itself and first
while (++hafIt != heH->prev()->facet_begin()) {
if (CGAL::do_intersect(checkSeg,Segment_3(hafIt->vertex()->point(),hafIt->prev()->vertex()->point())))
return false;
}
if (!isOpposite)
return triDoesNotIntersectFacet (heH->opposite(), true);
else
return true;
}
void Scene_polyhedron_selection_item::compute_elements()
{
positions_facets.clear();
positions_lines.clear();
positions_points.clear();
normals.clear();
//The facets
{
for(Selection_set_facet::iterator
it = selected_facets.begin(),
end = selected_facets.end();
it != end; ++it)
{
const Kernel::Vector_3 n =
CGAL::Polygon_mesh_processing::compute_face_normal(*it, *this->poly_item->polyhedron());
normals.push_back(n.x());
normals.push_back(n.y());
normals.push_back(n.z());
normals.push_back(n.x());
normals.push_back(n.y());
normals.push_back(n.z());
normals.push_back(n.x());
normals.push_back(n.y());
normals.push_back(n.z());
Polyhedron::Halfedge_around_facet_circulator
he = (*it)->facet_begin(),
cend = he;
CGAL_For_all(he,cend)
{
const Kernel::Point_3& p = he->vertex()->point();
positions_facets.push_back(p.x());
positions_facets.push_back(p.y());
positions_facets.push_back(p.z());
}
}
}
//The Lines
{
for(Selection_set_edge::iterator it = selected_edges.begin(); it != selected_edges.end(); ++it) {
const Kernel::Point_3& a = (it->halfedge())->vertex()->point();
const Kernel::Point_3& b = (it->halfedge())->opposite()->vertex()->point();
positions_lines.push_back(a.x());
positions_lines.push_back(a.y());
positions_lines.push_back(a.z());
positions_lines.push_back(b.x());
positions_lines.push_back(b.y());
positions_lines.push_back(b.z());
}
}
//The points
{
for(Selection_set_vertex::iterator
it = selected_vertices.begin(),
end = selected_vertices.end();
it != end; ++it)
{
const Kernel::Point_3& p = (*it)->point();
positions_points.push_back(p.x());
positions_points.push_back(p.y());
positions_points.push_back(p.z());
}
}
}