BiomePainter.History.HistoryManager.MovePrevious C# (CSharp) Метод

        public bool MovePrevious()
        {
            if (undoStack.Count == 0)
                return false;

            do
            {
                redoStack.AddLast(undoStack.Last.Value);
                undoStack.RemoveLast();
            }
            while (undoStack.Count > 0 && undoStack.Last.Value.PreviousAction == null);

            return undoStack.Count > 0;
        }