C++ Face_handle::neighbor方法代码示例

void Foam::CV2D::fast_restore_Delaunay(Vertex_handle vh)
{
    int i;
    Face_handle f = vh->face(), next, start(f);

    do
    {
        i=f->index(vh);
        if (!is_infinite(f))
        {
            if (!internal_flip(f, cw(i))) external_flip(f, i);
            if (f->neighbor(i) == start) start = f;
        }
        f = f->neighbor(cw(i));
    } while (f != start);
}

void findOutsideSegment( Triangulation &t, Face_handle fh, int currentSegment, int commingFromIndex, int &outsideSegment )
{

	// if the face is an infinite face
	// then we know the outside segment which is the
	// current segment
	if( t.is_infinite(fh) )
	{
		if( (outsideSegment != -1)&&(outsideSegment != currentSegment) )
			printf( "error : different outsideSegments detected during triangulation (edgeloop not closed?)\n" );
		outsideSegment = currentSegment;
		return;
	}

	// if there is already a segment identifier, then we know that
	// the face has already been visited
	if( fh->info() != -1 )
		return;

	fh->info() = currentSegment;

	for( int i=0; i<3; ++i )
	{
		// get edge associated with the index i
		std::pair<Face_handle, int> edge = std::make_pair( fh, i );

		if( i == commingFromIndex )
			continue;
		

		// if the edge is a constrained edge, then we know this is the border
		if(t.is_constrained(edge))
		{
			//...and we have to pass a madified currentSegment value
			findOutsideSegment( t, fh->neighbor(i), (currentSegment+1)%2, t.mirror_index( fh, i), outsideSegment );
		}else
			//...else we recurse and leave the currentSegment value untouched
			findOutsideSegment( t, fh->neighbor(i), currentSegment, t.mirror_index( fh, i), outsideSegment );
	}
}

void Foam::CV2D::external_flip(Face_handle& f, int i)
{
    Face_handle n = f->neighbor(i);

    if
    (
        CGAL::ON_POSITIVE_SIDE
     != side_of_oriented_circle(n, f->vertex(i)->point())
    ) return;

    flip(f, i);
    i = n->index(f->vertex(i));
    external_flip(n, i);
}

bool recurse(Face_handle current_face, long d, vector<Face_handle>& visited, Triangulation t) {

	// Remember we visited this node
	visited.push_back(current_face);

	cout << "Recursion at: " << t.dual(current_face) << endl;

	// Base of recursion: check if we are free
	if(t.is_infinite(current_face)) {
		cout << "Infinite face!" << endl;
		return true;
	}

	for(int neighbor_num=0; neighbor_num<3; neighbor_num++) {
		Face_handle neighbor_face = current_face->neighbor(neighbor_num);
		//cout << (current_face == neighbor_face) << endl;
		cout << "\tChecking neighbor of vertex " << current_face->vertex(neighbor_num)->point() << endl;

		cout << "\tPoints: ";
		for(int j=0; j<3; j++) {
			cout << neighbor_face->vertex(j)->point() << ", ";
		}
		cout << endl;

		// If we already visited
		if(find(visited.begin(), visited.end(), current_face) != visited.end()) {
			continue;
		}

		Vertex_handle border_endpoint1 = current_face->vertex((neighbor_num + 1) % 3);
		Vertex_handle border_endpoint2 = current_face->vertex((neighbor_num + 2) % 3);
		K::FT border_length_sq = CGAL::squared_distance(border_endpoint1->point(), border_endpoint2->point());

		if(CGAL::to_double(border_length_sq) >= 4 * d) {	// If we can fit through that edge 
			// cout << "can fit through edge " << neighbor_num << endl;

			// New search starting from neighbor
			if(recurse(neighbor_face, d, visited, t)) {
				return true;
			}
		} else {
			cout << "cannot fit through edge :S" << endl;
		}
	}

	return false;
}

void
discoverInfiniteComponent(const CDT & ct)
{
  //when this function is called, all faces are set "in_domain"
  Face_handle start = ct.infinite_face();
  std::list<Face_handle> queue;
  queue.push_back(start);

  while(! queue.empty())
  {
    Face_handle fh = queue.front();
    queue.pop_front();
    fh->set_in_domain(false);
	
    for(int i = 0; i < 3; i++)
    {
      Face_handle fi = fh->neighbor(i);
      if(fi->is_in_domain()
        && !ct.is_constrained(CDT::Edge(fh,i)))
        queue.push_back(fi);
    }
  }
}

void Foam::CV2D::extractPatches
(
    wordList& patchNames,
    labelList& patchSizes,
    EdgeMap<label>& mapEdgesRegion,
    EdgeMap<label>& indirectPatchEdge
) const
{
    label nPatches = qSurf_.patchNames().size() + 1;
    label defaultPatchIndex = qSurf_.patchNames().size();

    patchNames.setSize(nPatches);
    patchSizes.setSize(nPatches, 0);
    mapEdgesRegion.clear();

    const wordList& existingPatches = qSurf_.patchNames();

    forAll(existingPatches, sP)
    {
        patchNames[sP] = existingPatches[sP];
    }

    patchNames[defaultPatchIndex] = "CV2D_default_patch";

    for
    (
        Triangulation::Finite_edges_iterator eit = finite_edges_begin();
        eit != finite_edges_end();
        ++eit
    )
    {
        Face_handle fOwner = eit->first;
        Face_handle fNeighbor = fOwner->neighbor(eit->second);

        Vertex_handle vA = fOwner->vertex(cw(eit->second));
        Vertex_handle vB = fOwner->vertex(ccw(eit->second));

        if
        (
            (vA->internalOrBoundaryPoint() && !vB->internalOrBoundaryPoint())
         || (vB->internalOrBoundaryPoint() && !vA->internalOrBoundaryPoint())
        )
        {
            point ptA = toPoint3D(vA->point());
            point ptB = toPoint3D(vB->point());

            label patchIndex = qSurf_.findPatch(ptA, ptB);

            if (patchIndex == -1)
            {
                patchIndex = defaultPatchIndex;

                WarningInFunction
                    << "Dual face found that is not on a surface "
                    << "patch. Adding to CV2D_default_patch."
                    << endl;
            }

            edge e(fOwner->faceIndex(), fNeighbor->faceIndex());
            patchSizes[patchIndex]++;
            mapEdgesRegion.insert(e, patchIndex);

            if (!pointPair(*vA, *vB))
            {
                indirectPatchEdge.insert(e, 1);
            }
        }
    }
}