Re: Review: FULLSCREEN_MONITORS Hint

[Grant Patterson <grantp vmware com>]

On Nov 24, 2007, at 11:48 a, Mark Tiefenbruck wrote:
> Presumably the monitors used will be a rectangular array. You could
> just specify a top-left and bottom-right monitor. Or maybe it would be
> easier to specify x- and y-coordinates in the root window, since
> monitors tend to be of different sizes. It really depends on what the
> applications are, I think.

Both of those are interesting ideas, in particular specifying root  
window coordinates. That would make this a bigger hint/property: an  
application could essentially place its window anywhere it wants,  
which might be more leeway than people are comfortable with. There  
could be some kind of sanity checking, but expecting the WM to  
confirm that the given coordinates actually specify a union of  
monitors would necessitate implementing a rather messy algorithm in  
each WM. What do people think about specifying x/y/width/height  
instead of a list of monitor indices?
> About your proposal, I think you should let each window manager decide
> what to do with transient windows, though I'd expect most will do what
> you suggested.

Sure. As Havoc suggested, I'll suggest the center-on-cursor's-monitor  
functionality, but not require it.

> Also, I don't see any reason the property should be
> written by the window manager and communicated through client
> messages. The client can add the hint to its own window with fewer
> context switches.

Lots of discussion over this issue. I'm pretty indifferent. The  
simple hint is easier to implement, and is the way I did things in  
preliminary patches for a few WMs. I see the advantages of the  
message/property setup, where the WM can refuse to cooperate, set the  
property itself, have defaults, etc. On the other hand, clients can  
indeed check for WM compliance by examining their geometry.

While I'm all for allowing WMs to reject FULLSCREEN_MONITORS  
requests, I really hope such cases are rare. The way we got here in  
the first place was WMs' reluctance to place windows over panels and  
other functionality designed to save the client window from itself.  
If FULLSCREEN_MONITORS doesn't work in reasonable circumstances,  
it'll be no better than the current hack we have to implement multi- 
monitor full screen.
>   Mark