/// This file is part of the X3DToolKit library
/// Copyright (C) 2002-2004  Yannick Le Goc (legoc@imag.fr)

/// http://artis.imag.fr/Members/Yannick.Legoc/X3D/

/// This library is free software; you can redistribute it and/or
/// modify it under the terms of the GNU Lesser General Public
/// License as published by the Free Software Foundation; either
/// version 2.1 of the License, or (at your option) any later version.

/// This library 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
/// Lesser General Public License for more details.

/// You should have received a copy of the GNU Lesser General Public
/// License along with this library; if not, write to the Free Software
/// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
#ifndef X3DTK_SFVEC2F_H
#define X3DTK_SFVEC2F_H

#include "Platform.h"

#include <math.h>
#include <iostream>

namespace X3DTK {

class SFString;
class SFPoint2f;

/*! \brief Class declared in <b><X3DTK/kernel.h></b> providing a 2D vector.
 * 
 *  SFVec2f is a vector in an affin space, which is different from a point represented
 *  by the SFPoint2f class. 
 *
 *  \ingroup base
 */

class SFVec2f
{
public:
  /// x coordinates.
  float x;
  /// y coordinates.
  float y;

  /// Constructor.
  SFVec2f();
  /// Constructor with x, y and z coordinates in parameters.
  SFVec2f(float x, float y);
  /// Copy constructor
  SFVec2f(const SFVec2f &v);
  /// Overloaded assignment operator.
  SFVec2f &operator= (const SFVec2f &v);
  /// Overloaded operator.
  SFVec2f &operator+= (const SFVec2f &v);
  /// Overloaded operator.
  SFVec2f &operator-= (const SFVec2f &v);
  /// Explicit constructor from a string of which format is "x y".
  explicit SFVec2f(const SFString &s); 
  /// Conversion from point to vector.
  explicit SFVec2f(const SFPoint2f &P);
  /// Bracket operator.
  inline float &operator[](int i) {return (&x)[i];};
  /// Bracket operator.
  inline const float &operator[](int i) const {return (&x)[i];};
  
  /// Overloaded operator==.
  friend bool operator== (const SFVec2f &v1, const SFVec2f &v2);
  /// Overloaded operator!=.
  friend bool operator!= (const SFVec2f &v1, const SFVec2f &v2);
  /// Overloaded operator+.
  friend SFVec2f operator+ (const SFVec2f &v1, const SFVec2f &v2);
  /// Overloaded operator-.
  friend SFVec2f operator- (const SFVec2f &v1, const SFVec2f &v2);
  /// Overloaded operator-.
  friend SFVec2f operator- (const SFVec2f &v);
  /// Overloaded operator*.
  friend float operator* (const SFVec2f &v1, const SFVec2f &v2);
  /// Overloaded operator*.
  friend SFVec2f operator* (const float a, const SFVec2f &v);
  /// Returns the norm of the vector.
  float norm() const;
  /// Normalizes the vector.
  SFVec2f normalize();
  /// Returns the vector normalized but doesn't change the vector.
  SFVec2f normalized() const;
  /// Returns the pointed array.
  inline float *f_data() {return &x;};
  /// Returns the pointed array.
  inline const float *f_data() const {return &x;};
  /// Returns the pointed array.
  inline operator float *() {return &x;};
  /// Returns the pointed array.
  inline operator const float *() const {return &x;};
  /// Converts into string.  
  SFString toSFString() const;
  
  /// Null vector.
  static const SFVec2f null;
};

}

#endif
