Re: Support for applications using different video resolutions

[Lubos Lunak <l lunak suse cz>]

On Monday 04 of August 2003 09:43, Ben Jansens wrote:
> Hello all,
>
> What follows is a proposal for better support for and interaction with
> applications which want to use different video resolutions from the
> default/current one. This applies to applications such as TV/movie viewers
> and games. On with the goods:
[snip]
> One place where the EWMH is lacking in this regard is video resolutions. At
> the present time, applications must set the video resolution themselves.
> This presents problems for both the applications and for the Window
> Manager:
>
> a) Applications must fight for the screen resolution if more than one is
> running which wishes to use a non-default resolution. Most likely the one
> started last wins, and the one started first can do nothing about it.

 Or it can be made that the one that has the focus controls the videomode. As 
good as your proposal.

>
> b) The Window Manager cannot control presentation to the user, and does not
> even know what is going on in regard to the screen resolution.

 Given that the videomode is usually changed in order to show a window that 
covers the whole "screen", I don't think there's any need that the window 
manager controls presentation to the user.

>
>     (side note: The VidMode extension has no events for modeline changes.)
[snip]
> At the current time, there is no way for applications to follow changes in
> the current modeline. Applications require this information. I am also
> currently working on adding events to the VidMode extension for this
> information, but changes to the XFree86 project are generally slow in
> coming, if ever. I am proposing the _NET_CURRENT_VIDMODE property on the
> root window to solve this problem. Any application can then easily
> determine and watch for changes to the resolution.

 Given that there still will be applications that won't follow you suggested 
specification, I don't see much difference between waiting for XFree86 to get 
vidmode notifications, and relying on _NET_CURRENT_VIDMODE.

 One more thing that interests me: Which applications would benefit from this? 
You said "This applies to applications such as TV/movie viewers and games."
- games - they usually grab the keyboard/mouse, so the WM won't get any chance 
to do anything, thus there's no advantage to having the app itself changing 
the videomode
- tv/movie viewers - what should be the advantage of this proposal when 
compared to switching vidmodes by the app itself on focusin/focusout ? (Let's 
ignore the fact that mplayer here doesn't seem to do anything with 
resolution, so this wouldn't even be for all of them).

-- 
Lubos Lunak
KDE developer
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