rotate.h

#pragma once
#include <Eigen/Geometry>

namespace Faunus {

class QuaternionRotate
{
  private:
    using Point = Eigen::Vector3d;
    Eigen::Quaterniond quaternion;
    Eigen::Matrix3d rotation_matrix;

  public:
    double angle = 0.0; 
    QuaternionRotate() = default;
    QuaternionRotate(double angle, Point axis);                     
    void set(double angle, Point axis);                             
    auto operator()(const Eigen::Matrix3d& matrix) const;           
    [[nodiscard]] const Eigen::Quaterniond& getQuaternion() const;  
    [[nodiscard]] const Eigen::Matrix3d& getRotationMatrix() const; 
    Point operator()(
        Point vector, std::function<void(Point&)> boundary = [](Point&) {},
        const Point& shift = {0, 0, 0}) const; 
};

} // namespace Faunus