+ // Flip the surface to make the changes visible. Note that the rectangle we
+ // flip is *superset* of the union of repainted rectangles (created as
+ // "rectangles union" by wxRect::Union) and so some parts of the back
+ // buffer that we didn't touch in this HandleQueuedPaintRequests call will
+ // be copied to the front buffer as well. This is safe/correct thing to do
+ // *only* because wx always use wxIDirectFBSurface::FlipToFront() and so
+ // the back and front buffers contain the same data.
+ //
+ // Note that we do _not_ split m_toPaint into disjoint rectangles and
+ // do FlipToFront() for each of them, because that could result in visible
+ // updating of the screen; instead, we prefer to flip everything at once.
+