/*---------------------------------------------------------------------------*\
  =========                 |
  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
   \\    /   O peration     |
    \\  /    A nd           | Copyright (C) 2011-2017 OpenFOAM Foundation
     \\/     M anipulation  | Copyright (C) 2017 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/>.

Class
    Foam::EulerCoordinateRotation

Description
    A coordinateRotation defined in the z-x-z (intrinsic) Euler convention.

    The 3 rotations are defined in the Euler intrinsic convention
    (around Z, around X' and around Z'').
    The order of the parameter arguments matches this rotation order.

    For reference and illustration, see
    http://mathworld.wolfram.com/EulerAngles.html
    and
    https://en.wikipedia.org/wiki/Euler_angles#Conventions

    Note, however, that it is the reverse transformation
    (local->global) that is defined here.

    - the rotation angles are in degrees, unless otherwise explicitly specified:

    \verbatim
    coordinateRotation
    {
        type        EulerRotation;
        degrees     false;
        rotation    (0 0 3.141592654);
    }
    \endverbatim

SourceFiles
    EulerCoordinateRotation.C

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

#ifndef EulerCoordinateRotation_H
#define EulerCoordinateRotation_H

#include "coordinateRotation.H"

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

namespace Foam
{

/*---------------------------------------------------------------------------*\
                   Class EulerCoordinateRotation Declaration
\*---------------------------------------------------------------------------*/

class EulerCoordinateRotation
:
    public coordinateRotation
{

    // Private Member Data

        //- Local-to-global transformation tensor
        tensor R_;

        //- Global-to-Local transformation tensor
        tensor Rtr_;


    // Private Member Functions

        //- Calculate transformation tensor
        void calcTransform
        (
            const scalar phiAngle,
            const scalar thetaAngle,
            const scalar psiAngle,
            const bool inDegrees
        );


public:

    //- Runtime type information
    TypeName("EulerRotation");


    // Constructors

        //- Construct null
        EulerCoordinateRotation();

        //- Construct as copy
        EulerCoordinateRotation(const EulerCoordinateRotation& r);

        //- Construct from rotation vector
        EulerCoordinateRotation
        (
            const vector& phiThetaPsi,
            const bool inDegrees
        );

        //- Construct from components of rotation vector
        EulerCoordinateRotation
        (
            const scalar phiAngle,
            const scalar thetaAngle,
            const scalar psiAngle,
            const bool inDegrees
        );

        //- Construct from dictionary
        explicit EulerCoordinateRotation(const dictionary& dict);

        //- Construct from dictionary and a registry (typically a mesh)
        EulerCoordinateRotation
        (
            const dictionary& dict,
            const objectRegistry& unused
        );

        //- Return clone
        autoPtr<coordinateRotation> clone() const
        {
            return autoPtr<coordinateRotation>
            (
                new EulerCoordinateRotation
                (
                    *this
                )
            );
        }


    // Member Functions

        //- Reset rotation to an identity rotation
        virtual void clear()
        {
            R_ = sphericalTensor::I;
            Rtr_ = sphericalTensor::I;
        }

        //- Update the rotation for a list of cells
        virtual void updateCells(const polyMesh&, const labelList&)
        {}

        //- Return local-to-global transformation tensor
        virtual const tensor& R() const
        {
            return R_;
        }

        //- Return global-to-local transformation tensor
        virtual const tensor& Rtr() const
        {
            return Rtr_;
        };

        //- Return local Cartesian x-axis in global coordinates
        virtual const vector e1() const
        {
            return Rtr_.x();
        }

        //- Return local Cartesian y-axis in global coordinates
        virtual const vector e2() const
        {
            return Rtr_.y();
        }

        //- Return local Cartesian z-axis in global coordinates
        virtual const vector e3() const
        {
            return Rtr_.z();
        }

        //- Return transformation tensor field
        virtual const tensorField& Tr() const;

        //- Transform vectorField using transformation tensor field
        virtual tmp<vectorField> transform(const vectorField& st) const;

        //- Transform vector using transformation tensor
        virtual vector transform(const vector& st) const;

        //- Inverse transform vectorField using transformation tensor field
        virtual tmp<vectorField> invTransform(const vectorField& st) const;

        //- Inverse transform vector using transformation tensor
        virtual vector invTransform(const vector& st) const;

        //- Transform tensor field using transformation tensorField
        virtual tmp<tensorField> transformTensor(const tensorField& st) const;

        //- Transform tensor using transformation tensorField
        virtual tensor transformTensor(const tensor& st) const;

        //- Transform tensor sub-field using transformation tensorField
        virtual tmp<tensorField> transformTensor
        (
            const tensorField& st,
            const labelList& cellMap
        ) const;

        //- Transform vectorField using transformation tensorField and return
        // symmetrical tensorField
        virtual tmp<symmTensorField> transformVector
        (
            const vectorField& st
        ) const;

        //- Transform vector using transformation tensor and return
        // symmetrical tensor
        virtual symmTensor transformVector(const vector& st) const;

};


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

} // End namespace Foam

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

#endif

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