Bevisuali.UX.Graph.GraphEdge.UpdateEdgeDirection C# (CSharp) Метод

        protected void UpdateEdgeDirection(object sender, EventArgs e)
        {
            // Parent coordinates.
            var to = _to.Position;
            var from = _from.Position;
            if (to.IsNaN() || from.IsNaN())
            {
                this.Visibility = System.Windows.Visibility.Collapsed;
                return;
            }

            var direction = to.Subtract(from);
            var length = direction.Magnitude();

            Debug.Assert(!double.IsNaN(length));

            if (length == 0)
            {
                this.Visibility = System.Windows.Visibility.Collapsed;
                return;
            }
            this.Visibility = System.Windows.Visibility.Visible;

            // Trim according to radii.
            var directionUnit = direction.Multiply(1.0 / length);
            var fromRadius = _from.ActualRadius * _from.GetRenderScale().Item1;
            var toRadius = _to.ActualRadius * _from.GetRenderScale().Item1;
            from = from.Add(directionUnit.Multiply(fromRadius));
            to = to.Subtract(directionUnit.Multiply(toRadius));
            length = Math.Max(length - fromRadius - toRadius, 0.0);

            // Resize this arrow.
            this.Length = length;

            // Position tip.
            Canvas.SetLeft(this, to.X);
            Canvas.SetTop(this, to.Y);

            // Rotate arrow.
            double angle = Math.Atan2(direction.Y, direction.X);
            RotateTransform transform = (RotateTransform)this.RenderTransform;
            transform.Angle = angle * 180.0 / (Math.PI) + 90;
        }