Implement LockWindowUpdate [take 3]

[Mike Hearn]

On Fri, 2004-01-16 at 22:39, Alexandre Julliard wrote:
> A DC would be concerned if it could have its visible region changed by
> the fact that the lock window is set, so this would be basically any
> DC used by the old and new lock windows and all their visible children.

Is 'concerned' a technical term? I've not seen it in the Wine sources
before. If so, is there a function anywhere to calculate the concerned
DCs given a window?

> > Could you have told me this when I first submitted my patch? I feel it's
> > been a bit of a waste of time now - looking at the code it seems that
> > inter-process invalidation is not trivial thing.
> 
> Pretty much nothing in the painting code is trivial I'm afraid...

At the moment the invalid region is stored in WND yes, and to implement
this properly it would have to be moved into the server and manipulated
using server RPCs? I'm not going to attempt this myself, just wondering
what it'd take (and maybe somebody will see this thread and write a
patch).