/// <summary>
/// Get the direction of the vector, or throw an <see cref="Exception"/> if the vector is short.
/// The length tolerance is set so that if a unit vector in 3D is projected into 2D, the projection is
/// considered too short when the original vector would be considered perpendicular to the xy-plane.
/// </summary>
public static Direction2D GetDirection(DoubleVector2D vector)
{
var magnitude = vector.GetMagnitude();
if (magnitude <= ZeroDotProductTolerance)
{
throw new ArgumentException("The vector is nearly zero.", nameof(vector));
}
return(new Direction2D(vector / magnitude));
}
private Direction2D(DoubleVector2D unitVector)
{
UnitVector = unitVector;
}