mappedPatchBase.C

/*---------------------------------------------------------------------------*\
  =========                 |
  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
   \\    /   O peration     |
    \\  /    A nd           | Copyright (C) 2011-2015 OpenFOAM Foundation
     \\/     M anipulation  | Copyright (C) 2015 OpenCFD Ltd.
-------------------------------------------------------------------------------
License
    This file is part of OpenFOAM.

    OpenFOAM 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.

    OpenFOAM 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 OpenFOAM.  If not, see <http://www.gnu.org/licenses/>.

\*---------------------------------------------------------------------------*/

#include "mappedPatchBase.H"
#include "addToRunTimeSelectionTable.H"
#include "ListListOps.H"
#include "meshSearchMeshObject.H"
#include "meshTools.H"
#include "OFstream.H"
#include "Random.H"
#include "treeDataFace.H"
#include "treeDataPoint.H"
#include "indexedOctree.H"
#include "polyMesh.H"
#include "polyPatch.H"
#include "Time.H"
#include "mapDistribute.H"
#include "SubField.H"
#include "triPointRef.H"
#include "syncTools.H"
#include "treeDataCell.H"
#include "DynamicField.H"

// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

namespace Foam
{
    defineTypeNameAndDebug(mappedPatchBase, 0);

    template<>
    const char* Foam::NamedEnum
    <
        Foam::mappedPatchBase::sampleMode,
        6
    >::names[] =
    {
        "nearestCell",
        "nearestPatchFace",
        "nearestPatchFaceAMI",
        "nearestPatchPoint",
        "nearestFace",
        "nearestOnlyCell"
    };

    template<>
    const char* Foam::NamedEnum
    <
        Foam::mappedPatchBase::offsetMode,
        3
    >::names[] =
    {
        "uniform",
        "nonuniform",
        "normal"
    };
}


const Foam::NamedEnum<Foam::mappedPatchBase::sampleMode, 6>
    Foam::mappedPatchBase::sampleModeNames_;

const Foam::NamedEnum<Foam::mappedPatchBase::offsetMode, 3>
    Foam::mappedPatchBase::offsetModeNames_;


// * * * * * * * * * * * * * Private Member Functions  * * * * * * * * * * * //

Foam::tmp<Foam::pointField> Foam::mappedPatchBase::facePoints
(
    const polyPatch& pp
) const
{
    const polyMesh& mesh = pp.boundaryMesh().mesh();

    // Force construction of min-tet decomp
    (void)mesh.tetBasePtIs();

    // Initialise to face-centre
    tmp<pointField> tfacePoints(new pointField(patch_.size()));
    pointField& facePoints = tfacePoints();

    forAll(pp, faceI)
    {
        facePoints[faceI] = facePoint
        (
            mesh,
            pp.start()+faceI,
            polyMesh::FACE_DIAG_TRIS
        ).rawPoint();
    }

    return tfacePoints;
}


void Foam::mappedPatchBase::collectSamples
(
    const pointField& facePoints,
    pointField& samples,
    labelList& patchFaceProcs,
    labelList& patchFaces,
    pointField& patchFc
) const
{
    // Collect all sample points and the faces they come from.
    {
        List<pointField> globalFc(Pstream::nProcs());
        globalFc[Pstream::myProcNo()] = facePoints;
        Pstream::gatherList(globalFc);
        Pstream::scatterList(globalFc);
        // Rework into straight list
        patchFc = ListListOps::combine<pointField>
        (
            globalFc,
            accessOp<pointField>()
        );
    }

    {
        List<pointField> globalSamples(Pstream::nProcs());
        globalSamples[Pstream::myProcNo()] = samplePoints(facePoints);
        Pstream::gatherList(globalSamples);
        Pstream::scatterList(globalSamples);
        // Rework into straight list
        samples = ListListOps::combine<pointField>
        (
            globalSamples,
            accessOp<pointField>()
        );
    }

    {
        labelListList globalFaces(Pstream::nProcs());
        globalFaces[Pstream::myProcNo()] = identity(patch_.size());
        // Distribute to all processors
        Pstream::gatherList(globalFaces);
        Pstream::scatterList(globalFaces);

        patchFaces = ListListOps::combine<labelList>
        (
            globalFaces,
            accessOp<labelList>()
        );
    }

    {
        labelList nPerProc(Pstream::nProcs());
        nPerProc[Pstream::myProcNo()] = patch_.size();
        Pstream::gatherList(nPerProc);
        Pstream::scatterList(nPerProc);

        patchFaceProcs.setSize(patchFaces.size());

        label sampleI = 0;
        forAll(nPerProc, procI)
        {
            for (label i = 0; i < nPerProc[procI]; i++)
            {
                patchFaceProcs[sampleI++] = procI;
            }
        }
    }
}


// Find the processor/cell containing the samples. Does not account
// for samples being found in two processors.
void Foam::mappedPatchBase::findSamples
(
    const sampleMode mode,
    const pointField& samples,
    labelList& sampleProcs,
    labelList& sampleIndices,
    pointField& sampleLocations
) const
{
    // Lookup the correct region
    const polyMesh& mesh = sampleMesh();

    // All the info for nearest. Construct to miss
    List<nearInfo> nearest(samples.size());

    switch (mode)
    {
        case NEARESTCELL:
        {
            if (samplePatch_.size() && samplePatch_ != "none")
            {
                FatalErrorIn
                (
                    "mappedPatchBase::findSamples(const pointField&,"
                    " labelList&, labelList&, pointField&) const"
                )   << "No need to supply a patch name when in "
                    << sampleModeNames_[mode] << " mode." << exit(FatalError);
            }

            //- Note: face-diagonal decomposition
            const indexedOctree<Foam::treeDataCell>& tree = mesh.cellTree();

            forAll(samples, sampleI)
            {
                const point& sample = samples[sampleI];

                label cellI = tree.findInside(sample);

                if (cellI == -1)
                {
                    nearest[sampleI].second().first() = Foam::sqr(GREAT);
                    nearest[sampleI].second().second() = Pstream::myProcNo();
                }
                else
                {
                    const point& cc = mesh.cellCentres()[cellI];

                    nearest[sampleI].first() = pointIndexHit
                    (
                        true,
                        cc,
                        cellI
                    );
                    nearest[sampleI].second().first() = magSqr(cc-sample);
                    nearest[sampleI].second().second() = Pstream::myProcNo();
                }
            }
            break;
        }

        case NEARESTONLYCELL:
        {
            if (samplePatch_.size() && samplePatch_ != "none")
            {
                FatalErrorIn
                (
                    "mappedPatchBase::findSamples(const pointField&,"
                    " labelList&, labelList&, pointField&) const"
                )   << "No need to supply a patch name when in "
                    << sampleModeNames_[mode] << " mode." << exit(FatalError);
            }

            //- Note: face-diagonal decomposition
            const indexedOctree<Foam::treeDataCell>& tree = mesh.cellTree();

            forAll(samples, sampleI)
            {
                const point& sample = samples[sampleI];

                nearest[sampleI].first() = tree.findNearest(sample, sqr(GREAT));
                nearest[sampleI].second().first() = magSqr
                (
                    nearest[sampleI].first().hitPoint()
                   -sample
                );
                nearest[sampleI].second().second() = Pstream::myProcNo();
            }
            break;
        }

        case NEARESTPATCHFACE:
        {
            Random rndGen(123456);

            const polyPatch& pp = samplePolyPatch();

            if (pp.empty())
            {
                forAll(samples, sampleI)
                {
                    nearest[sampleI].second().first() = Foam::sqr(GREAT);
                    nearest[sampleI].second().second() = Pstream::myProcNo();
                }
            }
            else
            {
                // patch faces
                const labelList patchFaces(identity(pp.size()) + pp.start());

                treeBoundBox patchBb
                (
                    treeBoundBox(pp.points(), pp.meshPoints()).extend
                    (
                        rndGen,
                        1e-4
                    )
                );
                patchBb.min() -= point(ROOTVSMALL, ROOTVSMALL, ROOTVSMALL);
                patchBb.max() += point(ROOTVSMALL, ROOTVSMALL, ROOTVSMALL);

                indexedOctree<treeDataFace> boundaryTree
                (
                    treeDataFace    // all information needed to search faces
                    (
                        false,      // do not cache bb
                        mesh,
                        patchFaces  // boundary faces only
                    ),
                    patchBb,        // overall search domain
                    8,              // maxLevel
                    10,             // leafsize
                    3.0             // duplicity
                );

                forAll(samples, sampleI)
                {
                    const point& sample = samples[sampleI];

                    pointIndexHit& nearInfo = nearest[sampleI].first();
                    nearInfo = boundaryTree.findNearest
                    (
                        sample,
                        magSqr(patchBb.span())
                    );

                    if (!nearInfo.hit())
                    {
                        nearest[sampleI].second().first() = Foam::sqr(GREAT);
                        nearest[sampleI].second().second() =
                            Pstream::myProcNo();
                    }
                    else
                    {
                        point fc(pp[nearInfo.index()].centre(pp.points()));
                        nearInfo.setPoint(fc);
                        nearest[sampleI].second().first() = magSqr(fc-sample);
                        nearest[sampleI].second().second() =
                            Pstream::myProcNo();
                    }
                }
            }
            break;
        }

        case NEARESTPATCHPOINT:
        {
            Random rndGen(123456);

            const polyPatch& pp = samplePolyPatch();

            if (pp.empty())
            {
                forAll(samples, sampleI)
                {
                    nearest[sampleI].second().first() = Foam::sqr(GREAT);
                    nearest[sampleI].second().second() = Pstream::myProcNo();
                }
            }
            else
            {
                // patch (local) points
                treeBoundBox patchBb
                (
                    treeBoundBox(pp.points(), pp.meshPoints()).extend
                    (
                        rndGen,
                        1e-4
                    )
                );
                patchBb.min() -= point(ROOTVSMALL, ROOTVSMALL, ROOTVSMALL);
                patchBb.max() += point(ROOTVSMALL, ROOTVSMALL, ROOTVSMALL);

                indexedOctree<treeDataPoint> boundaryTree
                (
                    treeDataPoint   // all information needed to search faces
                    (
                        mesh.points(),
                        pp.meshPoints() // selection of points to search on
                    ),
                    patchBb,        // overall search domain
                    8,              // maxLevel
                    10,             // leafsize
                    3.0             // duplicity
                );

                forAll(samples, sampleI)
                {
                    const point& sample = samples[sampleI];

                    pointIndexHit& nearInfo = nearest[sampleI].first();
                    nearInfo = boundaryTree.findNearest
                    (
                        sample,
                        magSqr(patchBb.span())
                    );

                    if (!nearInfo.hit())
                    {
                        nearest[sampleI].second().first() = Foam::sqr(GREAT);
                        nearest[sampleI].second().second() =
                            Pstream::myProcNo();
                    }
                    else
                    {
                        const point& pt = nearInfo.hitPoint();

                        nearest[sampleI].second().first() = magSqr(pt-sample);
                        nearest[sampleI].second().second() =
                            Pstream::myProcNo();
                    }
                }
            }
            break;
        }

        case NEARESTFACE:
        {
            if (samplePatch().size() && samplePatch() != "none")
            {
                FatalErrorIn
                (
                    "mappedPatchBase::findSamples(const pointField&,"
                    " labelList&, labelList&, pointField&) const"
                )   << "No need to supply a patch name when in "
                    << sampleModeNames_[mode] << " mode." << exit(FatalError);
            }

            //- Note: face-diagonal decomposition
            const meshSearchMeshObject& meshSearchEngine =
                meshSearchMeshObject::New(mesh);

            forAll(samples, sampleI)
            {
                const point& sample = samples[sampleI];

                label faceI = meshSearchEngine.findNearestFace(sample);

                if (faceI == -1)
                {
                    nearest[sampleI].second().first() = Foam::sqr(GREAT);
                    nearest[sampleI].second().second() = Pstream::myProcNo();
                }
                else
                {
                    const point& fc = mesh.faceCentres()[faceI];

                    nearest[sampleI].first() = pointIndexHit
                    (
                        true,
                        fc,
                        faceI
                    );
                    nearest[sampleI].second().first() = magSqr(fc-sample);
                    nearest[sampleI].second().second() = Pstream::myProcNo();
                }
            }
            break;
        }

        case NEARESTPATCHFACEAMI:
        {
            // nothing to do here
            return;
        }

        default:
        {
            FatalErrorIn("mappedPatchBase::findSamples(..)")
                << "problem." << abort(FatalError);
        }
    }


    // Find nearest. Combine on master.
    Pstream::listCombineGather(nearest, nearestEqOp());
    Pstream::listCombineScatter(nearest);


    if (debug)
    {
        Info<< "mappedPatchBase::findSamples on mesh " << sampleRegion()
            << " : " << endl;
        forAll(nearest, sampleI)
        {
            label procI = nearest[sampleI].second().second();
            label localI = nearest[sampleI].first().index();

            Info<< "    " << sampleI << " coord:"<< samples[sampleI]
                << " found on processor:" << procI
                << " in local cell/face/point:" << localI
                << " with location:" << nearest[sampleI].first().rawPoint()
                << endl;
        }
    }

    // Convert back into proc+local index
    sampleProcs.setSize(samples.size());
    sampleIndices.setSize(samples.size());
    sampleLocations.setSize(samples.size());

    forAll(nearest, sampleI)
    {
        if (!nearest[sampleI].first().hit())
        {
            sampleProcs[sampleI] = -1;
            sampleIndices[sampleI] = -1;
            sampleLocations[sampleI] = vector::max;
        }
        else
        {
            sampleProcs[sampleI] = nearest[sampleI].second().second();
            sampleIndices[sampleI] = nearest[sampleI].first().index();
            sampleLocations[sampleI] = nearest[sampleI].first().hitPoint();
        }
    }
}


void Foam::mappedPatchBase::calcMapping() const
{
    static bool hasWarned = false;
    if (mapPtr_.valid())
    {
        FatalErrorIn("mappedPatchBase::calcMapping() const")
            << "Mapping already calculated" << exit(FatalError);
    }

    // Get points on face (since cannot use face-centres - might be off
    // face-diagonal decomposed tets.
    tmp<pointField> patchPoints(facePoints(patch_));

    // Get offsetted points
    const pointField offsettedPoints(samplePoints(patchPoints()));

    // Do a sanity check - am I sampling my own patch?
    // This only makes sense for a non-zero offset.
    bool sampleMyself =
    (
        mode_ == NEARESTPATCHFACE
     && sampleRegion() == patch_.boundaryMesh().mesh().name()
     && samplePatch() == patch_.name()
    );

    // Check offset
    vectorField d(offsettedPoints-patchPoints());
    bool coincident = (gAverage(mag(d)) <= ROOTVSMALL);

    if (sampleMyself && coincident)
    {
        WarningIn
        (
            "mappedPatchBase::mappedPatchBase\n"
            "(\n"
            "    const polyPatch& pp,\n"
            "    const word& sampleRegion,\n"
            "    const sampleMode mode,\n"
            "    const word& samplePatch,\n"
            "    const vector& offset\n"
            ")\n"
        )   << "Invalid offset " << d << endl
            << "Offset is the vector added to the patch face centres to"
            << " find the patch face supplying the data." << endl
            << "Setting it to " << d
            << " on the same patch, on the same region"
            << " will find the faces themselves which does not make sense"
            << " for anything but testing." << endl
            << "patch_:" << patch_.name() << endl
            << "sampleRegion_:" << sampleRegion() << endl
            << "mode_:" << sampleModeNames_[mode_] << endl
            << "samplePatch_:" << samplePatch() << endl
            << "offsetMode_:" << offsetModeNames_[offsetMode_] << endl;
    }

    // Get global list of all samples and the processor and face they come from.
    pointField samples;
    labelList patchFaceProcs;
    labelList patchFaces;
    pointField patchFc;
    collectSamples
    (
        patchPoints,
        samples,
        patchFaceProcs,
        patchFaces,
        patchFc
    );

    // Find processor and cell/face samples are in and actual location.
    labelList sampleProcs;
    labelList sampleIndices;
    pointField sampleLocations;
    findSamples(mode_, samples, sampleProcs, sampleIndices, sampleLocations);

    // Check for samples that were not found. This will only happen for
    // NEARESTCELL since finds cell containing a location
    if (mode_ == NEARESTCELL)
    {
        label nNotFound = 0;
        forAll(sampleProcs, sampleI)
        {
            if (sampleProcs[sampleI] == -1)
            {
                nNotFound++;
            }
        }
        reduce(nNotFound, sumOp<label>());

        if (nNotFound > 0)
        {
            if (!hasWarned)
            {
                WarningIn
                (
                    "mappedPatchBase::mappedPatchBase\n"
                    "(\n"
                    "    const polyPatch& pp,\n"
                    "    const word& sampleRegion,\n"
                    "    const sampleMode mode,\n"
                    "    const word& samplePatch,\n"
                    "    const vector& offset\n"
                    ")\n"
                )   << "Did not find " << nNotFound
                    << " out of " << sampleProcs.size() << " total samples."
                    << " Sampling these on owner cell centre instead." << endl
                    << "On patch " << patch_.name()
                    << " on region " << sampleRegion()
                    << " in mode " << sampleModeNames_[mode_] << endl
                    << "with offset mode " << offsetModeNames_[offsetMode_]
                    << ". Suppressing further warnings from " << type() << endl;

                hasWarned = true;
            }

            // Collect the samples that cannot be found
            DynamicList<label> subMap;
            DynamicField<point> subSamples;

            forAll(sampleProcs, sampleI)
            {
                if (sampleProcs[sampleI] == -1)
                {
                    subMap.append(sampleI);
                    subSamples.append(samples[sampleI]);
                }
            }

            // And re-search for pure nearest (should not fail)
            labelList subSampleProcs;
            labelList subSampleIndices;
            pointField subSampleLocations;
            findSamples
            (
                NEARESTONLYCELL,
                subSamples,
                subSampleProcs,
                subSampleIndices,
                subSampleLocations
            );

            // Insert
            UIndirectList<label>(sampleProcs, subMap) = subSampleProcs;
            UIndirectList<label>(sampleIndices, subMap) = subSampleIndices;
            UIndirectList<point>(sampleLocations, subMap) = subSampleLocations;
        }
    }

    // Now we have all the data we need:
    // - where sample originates from (so destination when mapping):
    //   patchFaces, patchFaceProcs.
    // - cell/face sample is in (so source when mapping)
    //   sampleIndices, sampleProcs.

    //forAll(samples, i)
    //{
    //    Info<< i << " need data in region "
    //        << patch_.boundaryMesh().mesh().name()
    //        << " for proc:" << patchFaceProcs[i]
    //        << " face:" << patchFaces[i]
    //        << " at:" << patchFc[i] << endl
    //        << "Found data in region " << sampleRegion()
    //        << " at proc:" << sampleProcs[i]
    //        << " face:" << sampleIndices[i]
    //        << " at:" << sampleLocations[i]
    //        << nl << endl;
    //}



    if (debug && Pstream::master())
    {
        OFstream str
        (
            patch_.boundaryMesh().mesh().time().path()
          / patch_.name()
          + "_mapped.obj"
        );
        Pout<< "Dumping mapping as lines from patch faceCentres to"
            << " sampled cell/faceCentres/points to file " << str.name()
            << endl;

        label vertI = 0;

        forAll(patchFc, i)
        {
            meshTools::writeOBJ(str, patchFc[i]);
            vertI++;
            meshTools::writeOBJ(str, sampleLocations[i]);
            vertI++;
            str << "l " << vertI-1 << ' ' << vertI << nl;
        }
    }

    // Determine schedule.
    mapPtr_.reset(new mapDistribute(sampleProcs, patchFaceProcs));

    // Rework the schedule from indices into samples to cell data to send,
    // face data to receive.

    labelListList& subMap = mapPtr_().subMap();
    labelListList& constructMap = mapPtr_().constructMap();

    forAll(subMap, procI)
    {
        subMap[procI] = UIndirectList<label>
        (
            sampleIndices,
            subMap[procI]
        );
        constructMap[procI] = UIndirectList<label>
        (
            patchFaces,
            constructMap[procI]
        );

        //if (debug)
        //{
        //    Pout<< "To proc:" << procI << " sending values of cells/faces:"
        //        << subMap[procI] << endl;
        //    Pout<< "From proc:" << procI
        //        << " receiving values of patch faces:"
        //        << constructMap[procI] << endl;
        //}
    }

    // Redo constructSize
    mapPtr_().constructSize() = patch_.size();

    if (debug)
    {
        // Check that all elements get a value.
        PackedBoolList used(patch_.size());
        forAll(constructMap, procI)
        {
            const labelList& map = constructMap[procI];

            forAll(map, i)
            {
                label faceI = map[i];

                if (used[faceI] == 0)
                {
                    used[faceI] = 1;
                }
                else
                {
                    FatalErrorIn("mappedPatchBase::calcMapping() const")
                        << "On patch " << patch_.name()
                        << " patchface " << faceI
                        << " is assigned to more than once."
                        << abort(FatalError);
                }
            }
        }
        forAll(used, faceI)
        {
            if (used[faceI] == 0)
            {
                FatalErrorIn("mappedPatchBase::calcMapping() const")
                    << "On patch " << patch_.name()
                    << " patchface " << faceI
                    << " is never assigned to."
                    << abort(FatalError);
            }
        }
    }
}


const Foam::autoPtr<Foam::searchableSurface>& Foam::mappedPatchBase::surfPtr()
const
{
    const word surfType(surfDict_.lookupOrDefault<word>("type", "none"));

    if (!surfPtr_.valid() && surfType != "none")
    {
        word surfName(surfDict_.lookupOrDefault("name", patch_.name()));

        const polyMesh& mesh = patch_.boundaryMesh().mesh();

        surfPtr_ =
            searchableSurface::New
            (
                surfType,
                IOobject
                (
                    surfName,
                    mesh.time().constant(),
                    "triSurface",
                    mesh,
                    IOobject::MUST_READ,
                    IOobject::NO_WRITE
                ),
                surfDict_
            );
    }

    return surfPtr_;
}


void Foam::mappedPatchBase::calcAMI() const
{
    if (AMIPtr_.valid())
    {
        FatalErrorIn("mappedPatchBase::calcAMI() const")
            << "AMI already calculated" << exit(FatalError);
    }

    AMIPtr_.clear();


    const polyPatch& nbr = samplePolyPatch();

    // Transform neighbour patch to local system
    pointField nbrPoints(samplePoints(nbr.localPoints()));

    primitivePatch nbrPatch0
    (
        SubList<face>
        (
            nbr.localFaces(),
            nbr.size()
        ),
        nbrPoints
    );


    if (debug)
    {
        OFstream os(patch_.name() + "_neighbourPatch-org.obj");
        meshTools::writeOBJ(os, samplePolyPatch().localFaces(), nbrPoints);

        OFstream osN(patch_.name() + "_neighbourPatch-trans.obj");
        meshTools::writeOBJ(osN, nbrPatch0, nbrPoints);

        OFstream osO(patch_.name() + "_ownerPatch.obj");
        meshTools::writeOBJ(osO, patch_.localFaces(), patch_.localPoints());
    }

    // Construct/apply AMI interpolation to determine addressing and weights
    AMIPtr_.reset
    (
        new AMIPatchToPatchInterpolation
        (
            patch_,
            nbrPatch0,
            surfPtr(),
            faceAreaIntersect::tmMesh,
            true,
            AMIPatchToPatchInterpolation::imFaceAreaWeight,
            -1,
            AMIReverse_
        )
    );
}


// Hack to read old (List-based) format. See Field.C. The difference
// is only that in case of falling back to old format it expects a non-uniform
// list instead of a single vector.
Foam::tmp<Foam::pointField> Foam::mappedPatchBase::readListOrField
(
    const word& keyword,
    const dictionary& dict,
    const label size
)
{
    tmp<pointField> tfld(new pointField());
    pointField& fld = tfld();

    if (size)
    {
        ITstream& is = dict.lookup(keyword);

        // Read first token
        token firstToken(is);

        if (firstToken.isWord())
        {
            if (firstToken.wordToken() == "uniform")
            {
                fld.setSize(size);
                fld = pTraits<vector>(is);
            }
            else if (firstToken.wordToken() == "nonuniform")
            {
                is >> static_cast<List<vector>&>(fld);
                if (fld.size() != size)
                {
                    FatalIOErrorIn
                    (
                        "mappedPatchBase::readListOrField"
                        "(const word& keyword, const dictionary&, const label)",
                        dict
                    )   << "size " << fld.size()
                        << " is not equal to the given value of " << size
                        << exit(FatalIOError);
                }
            }
            else
            {
                FatalIOErrorIn
                (
                    "mappedPatchBase::readListOrField"
                    "(const word& keyword, const dictionary&, const label)",
                    dict
                )   << "expected keyword 'uniform' or 'nonuniform', found "
                    << firstToken.wordToken()
                    << exit(FatalIOError);
            }
        }
        else
        {
            if (is.version() == 2.0)
            {
                IOWarningIn
                (
                    "mappedPatchBase::readListOrField"
                    "(const word& keyword, const dictionary&, const label)",
                    dict
                )   << "expected keyword 'uniform' or 'nonuniform', "
                       "assuming List format for backwards compatibility."
                       "Foam version 2.0." << endl;

                is.putBack(firstToken);
                is >> static_cast<List<vector>&>(fld);
            }
        }
    }
    return tfld;
}


// * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * * * * * //

Foam::mappedPatchBase::mappedPatchBase
(
    const polyPatch& pp
)
:
    patch_(pp),
    sampleRegion_(patch_.boundaryMesh().mesh().name()),
    mode_(NEARESTPATCHFACE),
    samplePatch_(""),
    coupleGroup_(),
    offsetMode_(UNIFORM),
    offset_(vector::zero),
    offsets_(pp.size(), offset_),
    distance_(0),
    sameRegion_(sampleRegion_ == patch_.boundaryMesh().mesh().name()),
    mapPtr_(NULL),
    AMIPtr_(NULL),
    AMIReverse_(false),
    surfPtr_(NULL),
    surfDict_(fileName("surface"))
{}


Foam::mappedPatchBase::mappedPatchBase
(
    const polyPatch& pp,
    const word& sampleRegion,
    const sampleMode mode,
    const word& samplePatch,
    const vectorField& offsets
)
:
    patch_(pp),
    sampleRegion_(sampleRegion),
    mode_(mode),
    samplePatch_(samplePatch),