Class molecule

Overview

Class molecule is the object-oriented representation of a generic molecule of arbitrary shape and mass in dynamic motion inside a 2-dimensional space.

Interface

Public members

• grid :: mark

  position of the molecule inside the engine grid.

• engine :: tag

  tags of the molecule in the engine context.

Constructors

• molecule()

  default constructor.

• molecule(const std :: vector<atom> & atoms, const vec & position = vec(0, 0), const vec & = velocity vec(0, 0), const double & orientation = 0, const double angular_velocity & = 0)

  builds a molecule with the given parameters and the given vector of atoms.

  REMARK: atoms’ position is absolute and is automatically altered in order to have the center of mass of the molecule at the given position.

Getters

• const size_t & size() const;
  As in number of atoms in the molecule.
• const vec & position() const;
• const vec & velocity() const;
• const double & orientation() const;
• const double & angular_velocity() const;
• const double & radius() const;
• const double & mass() const;
• const double & inertia_moment() const;
• const double & time() const;

• const int32_t & version() const; The version getter is utilized by the engine’s event system in order to check whether or not the molecule has to perform a specific predicted collision.

• const double energy() const;

Methods

• void integrate(const double & time)

  integrates the motion of the molecule at a given time. REMARK: does nothing if the given time is less or equal of the starting time of the molecule (a molecule can’t go backwards in time).

• void impulse(const vec & point_of_application, const vec & impulse)

  given an impulse and a point of application on the molecule, computes the effects of the impulse and updates molecule’s velocity and angular_velocity.

• void teleport(const vec :: fold & fold)

  given a fold enum (see vec reference for more details), translates the molecule inside the toroidal engine.

• void scale_energy(const double &)

  given a new amount of energy, rescales the velocity and the angular_velocity of the molecule accordingly.

• void disable()

  activates the disabled tag of the molecule and, therefore, the molecule stops interacting whith other objects inside the engine and will be removed shortly after by the garbage collector.

Operators

• const atom & operator [] (const size_t &) const

  access an atom that constitutes the molecule.

• molecule & operator ++ ()

  increments molecule’s version.

• molecule operator ++ (int)

  increments molecule’s version.