/// <summary>
/// Sets up the path walk state
/// </summary>
/// <param name="path">Path to walk</param>
/// <param name="pt">Position of the object about to walk the path</param>
/// <exception cref="ArgumentNullException">Thrown if path is null</exception>
public PathWalkState( IPath path, Point3 pt )
{
if ( path == null )
{
throw new ArgumentNullException( "path" );
}
m_Path = path;
m_T = path.GetClosestPoint( pt );
path.GetFrame( m_T, out m_Point, out m_Direction );
}