primitiveMeshFindCell.C

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/*---------------------------------------------------------------------------*\
  =========                 |
  \\      /  F ield         | foam-extend: Open Source CFD
   \\    /   O peration     | Version:     3.2
    \\  /    A nd           | Web:         http://www.foam-extend.org
     \\/     M anipulation  | For copyright notice see file Copyright
-------------------------------------------------------------------------------
License
    This file is part of foam-extend.
 
    foam-extend is free software: you can redistribute it and/or modify it
    under the terms of the GNU General Public License as published by the
    Free Software Foundation, either version 3 of the License, or (at your
    option) any later version.
 
    foam-extend is distributed in the hope that it will be useful, but
    WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    General Public License for more details.
 
    You should have received a copy of the GNU General Public License
    along with foam-extend.  If not, see <http://www.gnu.org/licenses/>.
 
\*---------------------------------------------------------------------------*/
 
#include "primitiveMesh.H"
#include "cell.H"
#include "boundBox.H"
 
// * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
 
// Is the point in the cell bounding box
bool Foam::primitiveMesh::pointInCellBB(const point& p, label celli) const
{
    // Make bounding box for check.  All points are local, so no reduce is
    // needed
    boundBox bb(cells()[celli].points(faces(), points()), false);
 
    return bb.contains(p);
}
 
 
// Is the point in the cell
bool Foam::primitiveMesh::pointInCell(const point& p, label celli) const
{
    const labelList& f = cells()[celli];
    const labelList& owner = this->faceOwner();
    const vectorField& cf = faceCentres();
    const vectorField& Sf = faceAreas();
 
    bool inCell = true;
 
    forAll(f, facei)
    {
        label nFace = f[facei];
        vector proj = p - cf[nFace];
        vector normal = Sf[nFace];
        if (owner[nFace] != celli)
        {
            normal = -normal;
        }
        inCell = inCell && ((normal & proj) <= 0);
    }
 
    return inCell;
}
 
 
// Find the cell with the nearest cell centre
Foam::label Foam::primitiveMesh::findNearestCell(const point& location) const
{
    const vectorField& centres = cellCentres();
 
    label nearestCelli = 0;
    scalar minProximity = magSqr(centres[0] - location);
 
    for (label celli = 1; celli < centres.size(); celli++)
    {
        scalar proximity = magSqr(centres[celli] - location);
 
        if (proximity < minProximity)
        {
            nearestCelli = celli;
            minProximity = proximity;
        }
    }
 
    return nearestCelli;
}
 
 
// Find cell enclosing this location
Foam::label Foam::primitiveMesh::findCell(const point& location) const
{
    if (nCells() == 0)
    {
        return -1;
    }
 
    // Find the nearest cell centre to this location
    label celli = findNearestCell(location);
 
    // If point is in the nearest cell return
    if (pointInCell(location, celli))
    {
        return celli;
    }
    else // point is not in the nearest cell so search all cells
    {
        bool cellFound = false;
        label n = 0;
 
        while ((!cellFound) && (n < nCells()))
        {
            if (pointInCell(location, n))
            {
                cellFound = true;
                celli = n;
            }
            else
            {
                n++;
            }
        }
        if (cellFound)
        {
            return celli;
        }
        else
        {
            return -1;
        }
    }
}
 
 
// ************************************************************************* //