Method distanceSquaredToLine

qcustomplot/qcustomplot.cpp:178–193

! \overload Returns the squared shortest distance of this vector (interpreted as a point) to the finite line segment given by \a start and \a end. \see distanceToStraightLine */

  \see distanceToStraightLine
*/
double QCPVector2D::distanceSquaredToLine(const QCPVector2D &start, const QCPVector2D &end) const
{
  QCPVector2D v(end-start);
  double vLengthSqr = v.lengthSquared();
  if (!qFuzzyIsNull(vLengthSqr))
  {
    double mu = v.dot(*this-start)/vLengthSqr;
    if (mu < 0)
      return (*this-start).lengthSquared();
    else if (mu > 1)
      return (*this-end).lengthSquared();
    else
      return ((start + mu*v)-*this).lengthSquared();
  } else
    return (*this-start).lengthSquared();
}

/*! \overload