Function locate

src/lagrangian/basic/particle/particle.C:437–518

void Foam::particle::locate
(
    const vector& position,
    const vector* direction,
    const label celli,
    const bool boundaryFail,
    const string boundaryMsg
)
{
    celli_ = celli;

    // Find the cell, if it has not been given
    if (celli_ < 0)
    {
        celli_ = mesh_.cellTree().findInside(position);
    }
    if (celli_ < 0)
    {
        FatalErrorInFunction
            << "Cell not found for particle position " << position << "."
            << exit(FatalError);
    }

    // Put the particle at the cell centre and in a random tet
    coordinates_ = barycentric(1, 0, 0, 0);
    tetFacei_ = mesh_.cells()[celli_][0];
    tetPti_ = 1;
    facei_ = -1;

    // Track to the injection point
    track(position - mesh_.cellCentres()[celli_], 0);
    if (!onFace())
    {
        return;
    }

    // We hit a boundary ...
    if (boundaryFail)
    {
        FatalErrorInFunction << boundaryMsg << exit(FatalError);
    }
    else
    {
        // Re-do the track, but this time do the bit tangential to the
        // direction/patch first. This gets us as close as possible to the
        // original path/position.

        if (direction == nullptr)
        {
            const polyPatch& p = mesh_.boundaryMesh()[patch()];
            direction = &p.faceNormals()[p.whichFace(facei_)];
        }

        const vector n = *direction/mag(*direction);
        const vector s = position - mesh_.cellCentres()[celli_];
        const vector sN = (s & n)*n;
        const vector sT = s - sN;