//public void AddLine( RectTransform a, RectTransform b )
        //{
        //    Debug.Log( "Adding line..." );

        //    var transformPair = new RectTransformPair( a, b );

        //    if ( TransformPairs.Contains( transformPair ) )
        //        throw new InvalidOperationException( "Line already defined." );

        //    TransformPairs.Add( transformPair );

        //    UpdateVertices();
        //}

        //public void RemoveLine( RectTransform a, RectTransform b )
        //{
        //    var transformPair = new RectTransformPair( a, b );

        //    if ( !TransformPairs.Contains( transformPair ) )
        //        throw new InvalidOperationException( "Line not defined." );

        //    TransformPairs.Remove( transformPair );

        //    UpdateVertices();
        //}

        public void SetLines(IEnumerable <RectTransformPair> pairs)
        {
            TransformPairs.Clear();

            if (pairs != null)
            {
                TransformPairs.AddRange(pairs);
            }

            UpdateVertices();
        }