simple XRANDR extension proposal

[Keith Packard]

Around 14 o'clock on Jul 23, John Meacham wrote:

> if XRANDR is present, then XReparentWindow behaves slightly differently, if
> the new parent window is on a screen other than the one the window is
> already on, then rather than generate a BadWindow error, the window will be
> reparented succesfully and a RANDR event will be generated and sent to the
> reparented window containing it's new root window information. an
> implementation may require that a compatable visual exist on the new
> screen. (which XReparentWindow requires on the same screen anyway)

That's a good idea, and one which I've been considering adding to XFIXES 
as it really has no relationship with RANDR.  There are additional tricks 
required here -- essentially all screen-specific resources (pixmaps, gcs, 
pictures) would need to be come screen-independent within the X server 
implementation.  I think it's all do-able, but it will take some 
experimentation and probably cooperation from applications -- you don't 
want to surprise them with a root change as that may break things badly.

-keith