void writeSurfaceToVTK
(
    const word& name,
    const triSurf& surf,
    const List<DynList<scalar, 1> >& data
)
{
    OFstream file(name+".vtk");

    writeSurfaceToVTK(file, surf);

    //- write curvature fields
    const pointField& points = surf.points();
    file << "\n";
    file << "\nPOINT_DATA " << points.size() << "\n";

    file << "SCALARS Values double\n";
    file << "LOOKUP_TABLE default\n";
    forAll(points, pI)
    {
        file << data[pI][0] << " ";

        if( pI && pI % 5 == 0 )
            file << endl;
    }
void writeSurfaceToVTK
(
    OFstream& file,
    const triSurf& surf,
    const DynList<label>& triangles,
    const labelHashSet& labels
)
{
    //- write the header
    file << "# vtk DataFile Version 3.0\n";
    file << "vtk output\n";
    file << "ASCII\n";
    file << "DATASET POLYDATA\n";

    //- write points
    std::map<label, label> newPointLabel;
    forAll(triangles, tI)
    {
        const labelledTri& tri = surf[triangles[tI]];

        for(label pI=0;pI<3;++pI)
        {
            newPointLabel[tri[pI]];
        }
    }

    forAllConstIter(labelHashSet, labels, it)
        newPointLabel[it.key()];

    const pointField& points = surf.points();
    file << "POINTS " << label(newPointLabel.size()) << " float\n";
    label counter(0);
    for
    (
        std::map<label, label>::iterator it=newPointLabel.begin();
        it!=newPointLabel.end();
        ++it
    )
    {
        it->second = counter++;

        const point& p = points[it->first];

        file << p.x() << ' ' << p.y() << ' ' << p.z() << ' ';

        file << nl;
    }

    //- write triangles
    file << "\n";
    file << "\nPOLYGONS " << triangles.size()
         << " " << 4*triangles.size() << endl;
    forAll(triangles, tI)
    {
        const labelledTri& tri = surf[triangles[tI]];

        file << 3
             << " " << newPointLabel[tri[0]]
             << " " << newPointLabel[tri[1]]
             << " " << newPointLabel[tri[2]] << endl;
    }
}