SipTransform.h

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// -*- LSST-C++ -*-

/*
 * LSST Data Management System
 * Copyright 2016 LSST/AURA
 *
 * This product includes software developed by the
 * LSST Project (http://www.lsst.org/).
 *
 * This program 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.
 *
 * This program 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 LSST License Statement and
 * the GNU General Public License along with this program.  If not,
 * see <http://www.lsstcorp.org/LegalNotices/>.
 */
#ifndef LSST_MEAS_ASTROM_SipTransform_INCLUDED
#define LSST_MEAS_ASTROM_SipTransform_INCLUDED

#include "lsst/afw/geom/LinearTransform.h"
#include "lsst/meas/astrom/PolynomialTransform.h"


namespace lsst { namespace afw { namespace image {

class TanWcs;

} // namespace image

namespace coord {

class Coord;

} // namespace coord

} // namespace afw

namespace meas { namespace astrom {

class SipTransformBase {
public:

    afw::geom::Point2D const & getPixelOrigin() const { return _pixelOrigin; }

    afw::geom::LinearTransform const & getCDMatrix() const { return _cdMatrix; }

    PolynomialTransform const & getPoly() const { return _poly; }

protected:

    SipTransformBase(
        afw::geom::Point2D const & pixelOrigin,
        afw::geom::LinearTransform const & cdMatrix,
        PolynomialTransform const & poly
    ) : _pixelOrigin(pixelOrigin),
        _cdMatrix(cdMatrix),
        _poly(poly)
    {}

    SipTransformBase(SipTransformBase const & other) = default;
    SipTransformBase(SipTransformBase && other) = default;
    SipTransformBase & operator=(SipTransformBase const & other) = default;
    SipTransformBase & operator=(SipTransformBase && other) = default;

    void swap(SipTransformBase & other) {
        std::swap(_pixelOrigin, other._pixelOrigin);
        std::swap(_cdMatrix, other._cdMatrix);
        _poly.swap(other._poly);
    }

    afw::geom::Point2D _pixelOrigin;
    afw::geom::LinearTransform _cdMatrix;
    PolynomialTransform _poly;
};


class SipForwardTransform : public SipTransformBase {
public:

    static SipForwardTransform convert(
        PolynomialTransform const & poly,
        afw::geom::Point2D const & pixelOrigin,
        afw::geom::LinearTransform const & cdMatrix
    );

    static SipForwardTransform convert(
        ScaledPolynomialTransform const & scaled,
        afw::geom::Point2D const & pixelOrigin,
        afw::geom::LinearTransform const & cdMatrix
    );

    static SipForwardTransform convert(ScaledPolynomialTransform const & scaled);

    SipForwardTransform(
        afw::geom::Point2D const & pixelOrigin,
        afw::geom::LinearTransform const & cdMatrix,
        PolynomialTransform const & forwardSipPoly
    ) :
        SipTransformBase(pixelOrigin, cdMatrix, forwardSipPoly)
    {}

    SipForwardTransform(SipForwardTransform const & other) = default;

    SipForwardTransform(SipForwardTransform && other) = default;

    SipForwardTransform & operator=(SipForwardTransform const & other) = default;

    SipForwardTransform & operator=(SipForwardTransform && other) = default;

    void swap(SipForwardTransform & other) {
        SipTransformBase::swap(other);
    }

    afw::geom::AffineTransform linearize(afw::geom::Point2D const & in) const;

    afw::geom::Point2D operator()(afw::geom::Point2D const & uv) const;

};


class SipReverseTransform : public SipTransformBase {
public:

    static SipReverseTransform convert(
        PolynomialTransform const & poly,
        afw::geom::Point2D const & pixelOrigin,
        afw::geom::LinearTransform const & cdMatrix
    );

    static SipReverseTransform convert(
        ScaledPolynomialTransform const & scaled,
        afw::geom::Point2D const & pixelOrigin,
        afw::geom::LinearTransform const & cdMatrix
    );

    static SipReverseTransform convert(ScaledPolynomialTransform const & scaled);

    SipReverseTransform(
        afw::geom::Point2D const & pixelOrigin,
        afw::geom::LinearTransform const & cdMatrix,
        PolynomialTransform const & reverseSipPoly
    ) : SipTransformBase(pixelOrigin, cdMatrix, reverseSipPoly),
        _cdInverse(cdMatrix.invert())
    {}

    SipReverseTransform(SipReverseTransform const & other) = default;

    SipReverseTransform(SipReverseTransform && other) = default;

    SipReverseTransform & operator=(SipReverseTransform const & other) = default;

    SipReverseTransform & operator=(SipReverseTransform && other) = default;

    void swap(SipReverseTransform & other) {
        SipTransformBase::swap(other);
        std::swap(_cdInverse, other._cdInverse);
    }

    afw::geom::AffineTransform linearize(afw::geom::Point2D const & in) const;

    afw::geom::Point2D operator()(afw::geom::Point2D const & xy) const;

private:
    friend class PolynomialTransform;
    friend class ScaledPolynomialTransform;
    afw::geom::LinearTransform _cdInverse;
};

std::shared_ptr<afw::image::TanWcs> makeWcs(
    SipForwardTransform const & sipForward,
    SipReverseTransform const & sipReverse,
    afw::coord::Coord const & skyOrigin
);

}}} // namespace lsst::meas::astrom

#endif // !LSST_MEAS_ASTROM_SipTransform_INCLUDED