/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */

/* vim:set ts=2 sw=2 sts=2 et cindent: */

/* This Source Code Form is subject to the terms of the Mozilla Public

 * License, v. 2.0. If a copy of the MPL was not distributed with this

 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#ifndef ThreeDPoint_h_

#define ThreeDPoint_h_

#include <cmath>

#include <algorithm>

namespace mozilla {

namespace dom {

struct ThreeDPoint final

{

  ThreeDPoint()

    : x(0.)

    , y(0.)

    , z(0.)

  {

  }

  ThreeDPoint(double aX, double aY, double aZ)

    : x(aX)

    , y(aY)

    , z(aZ)

  {

  }

  double Magnitude() const

  {

    return sqrt(x * x + y * y + z * z);

  }

  void Normalize()

  {

    // Zero vectors cannot be normalized. For our purpose, normalizing a zero

    // vector results in a zero vector.

    if (IsZero()) {

      return;

    }

    // Normalize with the maximum norm first to avoid overflow and underflow.

    double invMax = 1 / MaxNorm();

    x *= invMax;

    y *= invMax;

    z *= invMax;

    double invDistance = 1 / Magnitude();

    x *= invDistance;

    y *= invDistance;

    z *= invDistance;

  }

  ThreeDPoint CrossProduct(const ThreeDPoint& rhs) const

  {

    return ThreeDPoint(y * rhs.z - z * rhs.y,

                       z * rhs.x - x * rhs.z,

                       x * rhs.y - y * rhs.x);

  }

  double DotProduct(const ThreeDPoint& rhs)

  {

    return x * rhs.x + y * rhs.y + z * rhs.z;

  }

  bool IsZero() const

  {

    return x == 0 && y == 0 && z == 0;

  }

  // For comparing two vectors of close to unit magnitude.

  bool FuzzyEqual(const ThreeDPoint& other);

  double x, y, z;

private:

  double MaxNorm() const

  {

    return std::max(fabs(x), std::max(fabs(y), fabs(z)));

  }

};

ThreeDPoint operator-(const ThreeDPoint& lhs, const ThreeDPoint& rhs);

ThreeDPoint operator*(const ThreeDPoint& lhs, const ThreeDPoint& rhs);

ThreeDPoint operator*(const ThreeDPoint& lhs, const double rhs);

bool operator==(const ThreeDPoint& lhs, const ThreeDPoint& rhs);

} // namespace dom

} // namespace mozilla

#endif