drawSize(): Integer;
The drawSize method of the Window class returns the number of entries in the drawing history. If the value of the autoRedraw property is false, the drawSize method returns zero (0). There are entries in the drawing history only if drawing has been performed on the form or control since the last clearGraphics or drawUndo method call.
The drawSize method provides the current size of the drawing history. Use this method to record a rollback point for the image to be used at a later point.