Returns <code>true</code> if the receiver does not cover any
area in the (x, y) coordinate plane, and <code>false</code> if
the receiver does cover some area in the plane.
@return <code>true</code> if the receiver is empty, and <code>false</code> otherwise
@exception SWTException <ul>
<li>ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed</li>
</ul>
Returns <code>true</code> if the receiver does not cover any area in the (x, y) coordinate plane, and <code>false</code> if the receiver does cover some area in the plane.
@return <code>true</code> if the receiver is empty, and <code>false</code> otherwise
@exception SWTException <ul> <li>ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed</li> </ul>