internal void StartDragging() { Rectangle boundingRect = new Rectangle( (int)BoundingCircleRadius, (int)BoundingCircleRadius, (int)(m_parent.SceneGraph.ViewportSize.X - BoundingCircleRadius), (int)(m_parent.SceneGraph.ViewportSize.Y - BoundingCircleRadius)); Vector2 withinBounds = boundingRect.Clamp(m_parent.HandPosition); DragStartLocation = withinBounds; CurrentKnobLocation = withinBounds; }