Extent.h

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/*
 * Developed for the LSST Data Management System.
 * This product includes software developed by the LSST Project
 * (https://www.lsst.org).
 * See the COPYRIGHT file at the top-level directory of this distribution
 * for details of code ownership.
 *
 * 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 GNU General Public License
 * along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

/*
 * A coordinate class intended to represent offsets and dimensions.
 */
#ifndef LSST_GEOM_EXTENT_H
#define LSST_GEOM_EXTENT_H

#include <tuple>
#include <type_traits>

#include "lsst/pex/exceptions.h"
#include "lsst/geom/CoordinateExpr.h"

namespace lsst {
namespace geom {

// These are present to avoid a static assertion for instantiating computeNorm() on integer types.
namespace detail {

template <int N>
double computeExtentNorm(Extent<double, N> const &s) {
    return s.asEigen().norm();
}

template <int N>
int computeExtentNorm(Extent<int, N> const &s) {
    throw LSST_EXCEPT(pex::exceptions::LogicError, "Cannot compute norm of integer extent");
#if 1  // make compilers happy in non-void function
    return -1;
#endif
}

}  // namespace detail

template <typename T, int N>
class ExtentBase : public CoordinateBase<Extent<T, N>, T, N> {
    typedef CoordinateBase<Extent<T, N>, T, N> Super;

public:
    ExtentBase(ExtentBase const &) = default;
    ExtentBase(ExtentBase &&) = default;
    ExtentBase &operator=(ExtentBase const &) = default;
    ExtentBase &operator=(ExtentBase &&) = default;
    ~ExtentBase() = default;

    T computeSquaredNorm() const { return this->asEigen().squaredNorm(); }

    T computeNorm() const { return detail::computeExtentNorm(static_cast<Extent<T, N> const &>(*this)); }

    bool operator==(Extent<T, N> const &other) const noexcept { return all(this->eq(other)); }

    bool operator!=(Extent<T, N> const &other) const noexcept { return any(this->ne(other)); }

    CoordinateExpr<N> eq(Extent<T, N> const &other) const noexcept;
    CoordinateExpr<N> ne(Extent<T, N> const &other) const noexcept;
    CoordinateExpr<N> lt(Extent<T, N> const &other) const noexcept;
    CoordinateExpr<N> le(Extent<T, N> const &other) const noexcept;
    CoordinateExpr<N> gt(Extent<T, N> const &other) const noexcept;
    CoordinateExpr<N> ge(Extent<T, N> const &other) const noexcept;
    CoordinateExpr<N> eq(T scalar) const noexcept(Super::IS_ELEMENT_NOTHROW_COPYABLE) {
        return this->eq(Extent<T, N>(scalar));
    }
    CoordinateExpr<N> ne(T scalar) const noexcept(Super::IS_ELEMENT_NOTHROW_COPYABLE) {
        return this->ne(Extent<T, N>(scalar));
    }
    CoordinateExpr<N> lt(T scalar) const noexcept(Super::IS_ELEMENT_NOTHROW_COPYABLE) {
        return this->lt(Extent<T, N>(scalar));
    }
    CoordinateExpr<N> le(T scalar) const noexcept(Super::IS_ELEMENT_NOTHROW_COPYABLE) {
        return this->le(Extent<T, N>(scalar));
    }
    CoordinateExpr<N> gt(T scalar) const noexcept(Super::IS_ELEMENT_NOTHROW_COPYABLE) {
        return this->gt(Extent<T, N>(scalar));
    }
    CoordinateExpr<N> ge(T scalar) const noexcept(Super::IS_ELEMENT_NOTHROW_COPYABLE) {
        return this->ge(Extent<T, N>(scalar));
    }

    Point<T, N> operator+(Point<T, N> const &other) const noexcept(Super::IS_ELEMENT_NOTHROW_COPYABLE);
    Extent<T, N> operator+(Extent<T, N> const &other) const noexcept(Super::IS_ELEMENT_NOTHROW_COPYABLE) {
        return Extent<T, N>(this->_vector + other._vector);
    }
    Extent<T, N> operator-(Extent<T, N> const &other) const noexcept(Super::IS_ELEMENT_NOTHROW_COPYABLE) {
        return Extent<T, N>(this->_vector - other._vector);
    }
    Extent<T, N> &operator+=(Extent<T, N> const &other) noexcept(Super::IS_ELEMENT_NOTHROW_ASSIGNABLE) {
        this->_vector += other._vector;
        return static_cast<Extent<T, N> &>(*this);
    }
    Extent<T, N> &operator-=(Extent<T, N> const &other) noexcept(Super::IS_ELEMENT_NOTHROW_ASSIGNABLE) {
        this->_vector -= other._vector;
        return static_cast<Extent<T, N> &>(*this);
    }
    Extent<T, N> operator+() const noexcept(Super::IS_ELEMENT_NOTHROW_COPYABLE) {
        return static_cast<Extent<T, N> const &>(*this);
    }
    Extent<T, N> operator-() const noexcept(Super::IS_ELEMENT_NOTHROW_COPYABLE) {
        return Extent<T, N>(-this->_vector);
    }

    Extent<T, N> operator*(T scalar) const noexcept(Super::IS_ELEMENT_NOTHROW_COPYABLE) {
        return Extent<T, N>(this->_vector * scalar);
    }
    Extent<T, N> &operator*=(T scalar) noexcept(Super::IS_ELEMENT_NOTHROW_ASSIGNABLE) {
        this->_vector *= scalar;
        return static_cast<Extent<T, N> &>(*this);
    }
    Extent<T, N> operator/(T scalar) const noexcept(Super::IS_ELEMENT_NOTHROW_COPYABLE) {
        return Extent<T, N>(this->_vector / scalar);
    }
    Extent<T, N> &operator/=(T scalar) noexcept(Super::IS_ELEMENT_NOTHROW_ASSIGNABLE) {
        this->_vector /= scalar;
        return static_cast<Extent<T, N> &>(*this);
    }

    Point<T, N> asPoint() const noexcept(Super::IS_ELEMENT_NOTHROW_COPYABLE);

    std::string toString() const {
        std::stringstream out;
        out << "Extent(";
        for (size_t i = 0; i < N; ++i) {
            if (i != 0) {
                out << ",";
            }
            out << (*this)[i];
        }
        out << ")";
        return out.str();
    }

protected:
    explicit ExtentBase(T val = static_cast<T>(0)) noexcept(Super::IS_ELEMENT_NOTHROW_COPYABLE)
            : Super(val) {}

    template <typename Vector>
    explicit ExtentBase(Eigen::MatrixBase<Vector> const &vector) : Super(vector) {}
};

template <typename T, int N>
class Extent : public ExtentBase<T, N> {
    typedef ExtentBase<T, N> Super;

public:
    typedef typename Super::EigenVector EigenVector;

    explicit Extent(T val = static_cast<T>(0)) noexcept(Super::IS_ELEMENT_NOTHROW_COPYABLE) : Super(val) {}

    explicit Extent(EigenVector const &vector) noexcept(Super::IS_ELEMENT_NOTHROW_COPYABLE) : Super(vector) {}

    explicit Extent(Point<T, N> const &other) noexcept(Super::IS_ELEMENT_NOTHROW_COPYABLE);

    template <typename U>
    explicit Extent(Extent<U, N> const &other) noexcept(IS_NOTHROW_CONVERTIBLE<T, U>);
    template <typename U>
    explicit Extent(Point<U, N> const &other) noexcept(IS_NOTHROW_CONVERTIBLE<T, U>);

    // Should be consistent with converting constructors
    Extent(Extent const &other) = default;
    Extent(Extent &&other) = default;
    ~Extent() = default;

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

    T computeSquaredNorm() const { return this->asEigen().squaredNorm(); }

    T computeNorm() const { return this->asEigen().norm(); }

    void swap(Extent &other) noexcept { this->_swap(other); }
};

template <typename T>
class Extent<T, 2> : public ExtentBase<T, 2> {
    typedef ExtentBase<T, 2> Super;

public:
    typedef typename Super::EigenVector EigenVector;

    explicit Extent(T val = static_cast<T>(0)) noexcept(Super::IS_ELEMENT_NOTHROW_COPYABLE) : Super(val) {}

    explicit Extent(EigenVector const &vector) noexcept(Super::IS_ELEMENT_NOTHROW_COPYABLE) : Super(vector) {}

    explicit Extent(Point<T, 2> const &other) noexcept(Super::IS_ELEMENT_NOTHROW_COPYABLE);

    template <typename U>
    explicit Extent(Extent<U, 2> const &other) noexcept(IS_NOTHROW_CONVERTIBLE<T, U>);
    template <typename U>
    explicit Extent(Point<U, 2> const &other) noexcept(IS_NOTHROW_CONVERTIBLE<T, U>);

    explicit Extent(T x, T y) noexcept(Super::IS_ELEMENT_NOTHROW_COPYABLE) : Super(EigenVector(x, y)) {}

    explicit Extent(T const xy[2]) noexcept(Super::IS_ELEMENT_NOTHROW_COPYABLE)
            : Super(EigenVector(xy[0], xy[1])) {}

    explicit Extent(std::pair<T, T> const &xy) noexcept(Super::IS_ELEMENT_NOTHROW_COPYABLE)
            : Super(EigenVector(xy.first, xy.second)) {}

    explicit Extent(std::tuple<T, T> const &xy) noexcept(Super::IS_ELEMENT_NOTHROW_COPYABLE)
            : Super(EigenVector(std::get<0>(xy), std::get<1>(xy))) {}

    // Should be consistent with converting constructors
    Extent(Extent const &other) = default;
    Extent(Extent &&other) = default;
    ~Extent() = default;

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

    void swap(Extent &other) noexcept { this->_swap(other); }
};

template <typename T>
class Extent<T, 3> : public ExtentBase<T, 3> {
    typedef ExtentBase<T, 3> Super;

public:
    typedef typename Super::EigenVector EigenVector;

    explicit Extent(T val = static_cast<T>(0)) noexcept(Super::IS_ELEMENT_NOTHROW_COPYABLE) : Super(val) {}

    explicit Extent(EigenVector const &vector) noexcept(Super::IS_ELEMENT_NOTHROW_COPYABLE) : Super(vector) {}

    explicit Extent(Point<T, 3> const &other) noexcept(Super::IS_ELEMENT_NOTHROW_COPYABLE);

    template <typename U>
    explicit Extent(Extent<U, 3> const &other) noexcept(IS_NOTHROW_CONVERTIBLE<T, U>);
    template <typename U>
    explicit Extent(Point<U, 3> const &other) noexcept(IS_NOTHROW_CONVERTIBLE<T, U>);

    explicit Extent(T x, T y, T z) noexcept(Super::IS_ELEMENT_NOTHROW_COPYABLE)
            : Super(EigenVector(x, y, z)) {}

    explicit Extent(T const xyz[3]) noexcept(Super::IS_ELEMENT_NOTHROW_COPYABLE)
            : Super(EigenVector(xyz[0], xyz[1], xyz[2])) {}

    explicit Extent(std::tuple<T, T, T> const &xyz) noexcept(Super::IS_ELEMENT_NOTHROW_COPYABLE)
            : Super(EigenVector(std::get<0>(xyz), std::get<1>(xyz), std::get<2>(xyz))) {}

    // Should be consistent with converting constructors
    Extent(Extent const &other) = default;
    Extent(Extent &&other) = default;
    ~Extent() = default;

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

    void swap(Extent &other) noexcept { this->_swap(other); }
};

// Constructor for any 2D type from 2I type
template <typename T>
template <typename U>
Extent<T, 2>::Extent(Extent<U, 2> const &other) noexcept(IS_NOTHROW_CONVERTIBLE<T, U>) {
    static_assert((!std::is_same<T, U>::value && std::is_integral<U>::value),
                  "can only construct from Extent of different but integral type");
    this->setX(static_cast<T>(other.getX()));
    this->setY(static_cast<T>(other.getY()));
};

template <typename T>
template <typename U>
Extent<T, 2>::Extent(Point<U, 2> const &other) noexcept(IS_NOTHROW_CONVERTIBLE<T, U>) {
    static_assert((!std::is_same<T, U>::value && std::is_integral<U>::value),
                  "can only construct from Extent of different but integral type");
    this->setX(static_cast<T>(other.getX()));
    this->setY(static_cast<T>(other.getY()));
};

// Constructor for any 3D type from 3I type
template <typename T>
template <typename U>
Extent<T, 3>::Extent(Extent<U, 3> const &other) noexcept(IS_NOTHROW_CONVERTIBLE<T, U>) {
    static_assert((!std::is_same<T, U>::value && std::is_integral<U>::value),
                  "can only construct from Extent of different but integral type");
    this->setX(static_cast<T>(other.getX()));
    this->setY(static_cast<T>(other.getY()));
    this->setZ(static_cast<T>(other.getZ()));
};

// Constructor for any 3D type from 3I type
template <typename T>
template <typename U>
Extent<T, 3>::Extent(Point<U, 3> const &other) noexcept(IS_NOTHROW_CONVERTIBLE<T, U>) {
    static_assert((!std::is_same<T, U>::value && std::is_integral<U>::value),
                  "can only construct from Extent of different but integral type");
    this->setX(static_cast<T>(other.getX()));
    this->setY(static_cast<T>(other.getY()));
    this->setZ(static_cast<T>(other.getZ()));
};

typedef Extent<int, 2> ExtentI;
typedef Extent<int, 2> Extent2I;
typedef Extent<int, 3> Extent3I;
typedef Extent<double, 2> ExtentD;
typedef Extent<double, 2> Extent2D;
typedef Extent<double, 3> Extent3D;

template <int N>
Extent<int, N> truncate(Extent<double, N> const &input) noexcept;

template <int N>
Extent<int, N> floor(Extent<double, N> const &input) noexcept;

template <int N>
Extent<int, N> ceil(Extent<double, N> const &input) noexcept;

// Some operators below need to take ExtentBase arguments rather than Extent to
// avoid ambiguous overloads (since some competing operators are defined as member
// functions on ExtentBase).

template <typename T, int N>
Extent<T, N> operator*(T scalar,
                       ExtentBase<T, N> const &rhs) noexcept(ExtentBase<T, N>::IS_ELEMENT_NOTHROW_COPYABLE) {
    return rhs * scalar;
}

template <int N>
Extent<double, N> operator*(ExtentBase<int, N> const &lhs, double rhs) noexcept {
    return Extent<double, N>(static_cast<Extent<int, N> const &>(lhs)) * rhs;
}

template <int N>
void operator*=(ExtentBase<int, N> &lhs, double rhs) noexcept {
    // use "N < 0" so assertion is dependent on template instantiation, instead of triggering all the time
    static_assert(N < 0, "In-place multiplication of Extent<int,N> by double would truncate.");
}

template <int N>
Extent<double, N> operator/(ExtentBase<int, N> const &lhs, double rhs) noexcept {
    return Extent<double, N>(static_cast<Extent<int, N> const &>(lhs)) / rhs;
}

template <int N>
void operator/=(ExtentBase<int, N> &lhs, double rhs) noexcept {
    // use "N < 0" so assertion is dependent on template instantiation, instead of triggering all the time
    static_assert(N < 0, "In-place division of Extent<int,N> by double would truncate.");
}

template <int N>
Extent<double, N> operator*(double lhs, ExtentBase<int, N> const &rhs) noexcept {
    return lhs * Extent<double, N>(static_cast<Extent<int, N> const &>(rhs));
}

template <int N>
Extent<double, N> operator+(Extent<double, N> const &lhs, Extent<int, N> const &rhs) noexcept {
    return lhs + Extent<double, N>(rhs);
}

template <int N>
Extent<double, N> &operator+=(Extent<double, N> &lhs, Extent<int, N> const &rhs) noexcept {
    return lhs += Extent<double, N>(rhs);
}

template <int N>
Extent<double, N> operator-(Extent<double, N> const &lhs, Extent<int, N> const &rhs) noexcept {
    return lhs - Extent<double, N>(rhs);
}

template <int N>
Extent<double, N> &operator-=(Extent<double, N> &lhs, Extent<int, N> const &rhs) noexcept {
    return lhs -= Extent<double, N>(rhs);
}

template <int N>
Extent<double, N> operator+(Extent<int, N> const &lhs, Extent<double, N> const &rhs) noexcept {
    return Extent<double, N>(lhs) + rhs;
}

template <int N>
Extent<double, N> operator-(Extent<int, N> const &lhs, Extent<double, N> const &rhs) noexcept {
    return Extent<double, N>(lhs) - rhs;
}

}  // namespace geom
}  // namespace lsst

#endif