TTwist2D.h

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/* +------------------------------------------------------------------------+
   |                     Mobile Robot Programming Toolkit (MRPT)            |
   |                          https://www.mrpt.org/                         |
   |                                                                        |
   | Copyright (c) 2005-2020, Individual contributors, see AUTHORS file     |
   | See: https://www.mrpt.org/Authors - All rights reserved.               |
   | Released under BSD License. See: https://www.mrpt.org/License          |
   +------------------------------------------------------------------------+ */
#pragma once

#include <mrpt/math/TPoseOrPoint.h>
#include <vector>

namespace mrpt::math
{
/** 2D twist: 2D velocity vector (vx,vy) + planar angular velocity (omega)
 * \sa mrpt::math::TTwist3D, mrpt::math::TPose2D
 */
struct TTwist2D : public internal::ProvideStaticResize<TTwist2D>
{
    enum
    {
        static_size = 3
    };
    /** Velocity components: X,Y (m/s) */
    double vx{.0}, vy{.0};
    /** Angular velocity (rad/s) */
    double omega{.0};

    /** Constructor from components */
    constexpr TTwist2D(double vx_, double vy_, double omega_)
        : vx(vx_), vy(vy_), omega(omega_)
    {
    }
    /** Default fast constructor. Initializes to zeros  */
    TTwist2D() = default;
    /** Coordinate access using operator[]. Order: vx,vy,vphi */
    double& operator[](size_t i)
    {
        switch (i)
        {
            case 0:
                return vx;
            case 1:
                return vy;
            case 2:
                return omega;
            default:
                throw std::out_of_range("index out of range");
        }
    }
    /** Coordinate access using operator[]. Order: vx,vy,vphi */
    constexpr double operator[](size_t i) const
    {
        switch (i)
        {
            case 0:
                return vx;
            case 1:
                return vy;
            case 2:
                return omega;
            default:
                throw std::out_of_range("index out of range");
        }
    }
    /** Transformation into vector */
    void asVector(std::vector<double>& v) const
    {
        v.resize(3);
        v[0] = vx;
        v[1] = vy;
        v[2] = omega;
    }
    /** Transform the (vx,vy) components for a counterclockwise rotation of
     * `ang` radians. */
    void rotate(const double ang);
    bool operator==(const TTwist2D& o) const;
    bool operator!=(const TTwist2D& o) const;
    /** Returns the pose increment of multiplying each twist component times
     * "dt" seconds. */
    mrpt::math::TPose2D operator*(const double dt) const;

    /** Scale factor */
    void operator*=(const double k)
    {
        vx *= k;
        vy *= k;
        omega *= k;
    }

    /** Returns a human-readable textual representation of the object (eg: "[vx
     * vy omega]", omega in deg/s)
     * \sa fromString
     */
    void asString(std::string& s) const;
    std::string asString() const
    {
        std::string s;
        asString(s);
        return s;
    }

    /** Set the current object value from a string generated by 'asString' (eg:
     * "[0.02 1.04 -45.0]" )
     * \sa asString
     * \exception std::exception On invalid format
     */
    void fromString(const std::string& s);

    static TTwist2D FromString(const std::string& s)
    {
        TTwist2D o;
        o.fromString(s);
        return o;
    }
};

mrpt::serialization::CArchive& operator>>(
    mrpt::serialization::CArchive& in, mrpt::math::TTwist2D& o);
mrpt::serialization::CArchive& operator<<(
    mrpt::serialization::CArchive& out, const mrpt::math::TTwist2D& o);

}  // namespace mrpt::math

namespace mrpt::typemeta
{
// Specialization must occur in the same namespace
MRPT_DECLARE_TTYPENAME_NO_NAMESPACE(TTwist2D, mrpt::math)

}  // namespace mrpt::typemeta