Finishing Composite to handle transformed windows

[Benjamin Herrenschmidt]

On Fri, 2006-01-06 at 16:30 -0800, Deron Johnson wrote:
> 
> Keith Packard wrote On 01/06/06 14:24,:
> 
> > If we're really going to support this in earnest, I suggest that all of
> > the usual configuration functions should work as if there were two
> > separate stacks of windows, the 'normal' and the 'topmost', so you
> > should be able to raise or lower topmost windows within the topmost set
> > using the normal set of operations. When a window is moved from 'normal'
> > to 'topmost', it should be placed at the bottom (?) of the topmost set.
> > Similarly, when moved from topmost to normal, it should appear on the
> > top of the normal windows.
> 
> Yes. The concept of a "topmost window stack" seems more general and it
> defines reasonable semantics for multiple top-most windows.

Why not arbitrary windows stacks then (with a depth) ? It would make
things easier for a whole lot of things like:

 - Those various "desklets" implementations that have been floating
around which are basically about putting widgets in the root window.
Those could become normal windows at a higher depth

 - Various "tooltips" and other "alerts" effects provided by some
environments really want to float above all windows. That would be a
layer above the normal one and below the "topmost"