Negotiating server screen size

[Pierre Ossman]

On Wed, 16 Sep 2009 17:18:11 +0200
Christophe Lohr <christophe.lohr at cegetel.net> wrote:

> 
> Excellent, it works!
> 
> However, this feature is about resizing screen of an existing session.
> It may have some funny effects:
> - let's start Xvnc on an big screen:
> $ ./Xvnc :2 -geometry 1600x1024 -once  -SecurityTypes none -query
> localhost -once
> 
> - then start vncviewer requesting a small screen:
> $ ./vncviewer DesktopSize=640x480 localhost:2
> 
> One can only see the top left corner of the xdm login window which is at
> the center of the 1600x1024  screen...
> Do windows receive any XWindow event to be warned that the screen size
> has changed?
> 

They can listen for a RandR specific notification that the screen has
changed, yes. If you try a modern desktop environment you'll notice
that it resizes when the screen changes (you can even control the
session size with the desktop screen configuration tools).

> 
> Another strange point is that the DesktopSize should belong to a short
> list of standards screens sizes... As far as I understand source code,
> it is in relation to xrandr !?
> 

You can select any resolution you want on the vncviewer command line.
The reason you see a finite set with the xrandr tool is because of the
way RandR works. What you see is a default list, but more resolutions
can be added.

Rgds
-- 
Pierre Ossman            OpenSource-based Thin Client Technology
System Developer         Telephone: +46-13-21 46 00
Cendio AB                Web: http://www.cendio.com