Configuration for multiple monitors

Configuration for multiple monitors

[Øyvind Harboe]

A good configuration option is no configuration option :-)

Is there any reason not to make -multiplemonitors default for XWin?

With the default setting, the default behaviour when extending the desktop to
two monitors is broken. This is a known problem.

A machine with a single monitor behaves correctly with the -multiplemonitors 
option. 

Perhaps this is already in the works:

http://sources.redhat.com/ml/cygwin-xfree/2003-12/msg00096.html


Øyvind

Re: Configuration for multiple monitors

[Harold L Hunt II]

Øyvind,

Give a man a fish, he eats for one day.  Teach a man to fish...

Source is viewable here:

http://pdx.freedesktop.org/cgi-bin/viewcvs.cgi/xc/programs/Xserver/hw/xwin/?cvsroot=xorg&only_with_tag=CYGWIN


Do the following:

1) Look at winprocarg.c/winInitializeDefaultScreens

2) Change the line:
	g_ScreenInfo[i].fMultipleMonitors = FALSE;
    to:
	g_ScreenInfo[i].fMultipleMonitors = TRUE;

3) Look at winprocarg.c/ddxProcessArgument

4) Find the section that starts with:
   /*
    * Look for the '-multiplemonitors' argument
    */

5) Add a similar section for -nomultimonitors and -nomultiplemonitors 
that sets the flag to FALSE instead of to TRUE.

6) Pull the CVS tree following the instructions here:
	http://xfree86.cygwin.com/devel/server/

7) Make your changes as above.

8) Run 'cvs -z3 diff -up > multi-monitor.diff' in hw/xwin and send in 
the patch.

9) I will compile it for you and post it in the next release.  If you 
want to compile it yourself, check the Contributor's Guide (mind you, it 
references the XFree86.org CVS tree, which has been replaced with 
freedesktop.org for us):

http://xfree86.cygwin.com/docs/cg/prog-build-native.html

Harold

Øyvind Harboe wrote:

> A good configuration option is no configuration option :-)
> 
> Is there any reason not to make -multiplemonitors default for XWin?
> 
> With the default setting, the default behaviour when extending the desktop to
> two monitors is broken. This is a known problem.
> 
> A machine with a single monitor behaves correctly with the -multiplemonitors 
> option. 
> 
> Perhaps this is already in the works:
> 
> http://sources.redhat.com/ml/cygwin-xfree/2003-12/msg00096.html
> 
> 
> Øyvind
> 
> 

Re: Configuration for multiple monitors

[Harold L Hunt II]

Øyvind,

Jack Tanner had some valid points for keeping -nomultiplemonitors.

The reason we won't just remove the -multiplemonitors option is a little 
easier:

1) XWin.exe does not print nor popup error messages when it exists; 
rather, it logs them to /tmp/XWin.log.

2) Removing the -multiplemonitors option will cause XWin.exe to fail to 
start.

3) Must users do not know to look at /tmp/XWin.log to see that they 
passed an invalid parameter.

4) We will start seeing lots of fun reports on the mailing list asking 
why XWin.exe is crashing on startup, when it is in fact just reporting 
that -multiplemonitors is an invalid parameter.

That is why we don't remove old parameters completely.  We don't want to 
waste time debugging non-problems caused by doing so.

Harold

Øyvind Harboe wrote:

> Harold,
> 
> perhaps the below should *always* be TRUE and there shouldn't be 
> an option at all?
> 
> g_ScreenInfo[i].fMultipleMonitors = TRUE;
> 
> If so, then the changes TBD are:
> 
> - remove the -multiplemontiors option
> - always set fMultipleMonitors=TRUE, or remove fMultipleMontiors altogether.
> 
> (Code removed is not code deleted; it is in CVS in case it needs to be summoned 
> at some point.)
> 
> 
> Thanks for these tips BTW:
> 
> http://www.cygwin.com/ml/cygwin-xfree/2004-01/msg00160.html
> 
> Øyvind
> 
> 
> 

Re: Configuration for multiple monitors

[Harold L Hunt II]

Jack,

Jack Tanner wrote:
> Øyvind Harboe wrote:
> 
>> perhaps the below should *always* be TRUE and there shouldn't be an 
>> option at all?
> 
> 
> No, I'd like -nomultiplemonitors to exist.
> 
> I have two monitors, but the second is usually turned off. Various X 
> client dialog boxes and application windows usually come up in the 
> center of my desktop, which means half on one monitor, and half on the 
> other. If that weren't annoying enough, it makes life sheer hell when 
> one monitor is turned off!
> 
> This is why I do not use -multiplemonitors, even though I /have/ 
> multiple monitors. Even when both monitors are turned on, it's plenty to 
> have one for X apps, and another for regular Windows apps.

That is pretty much why I would want to make sure we have a 
-nomultiplemonitors switch.  In fact, we should finally look into a 
system to allow the user to specify which screen we should start up on. 
  That would be nice.

> Granted, the real solution to this issue would be to play nice with 
> nVidia's nView software. It offers these modes for dual-monitor work 
> (the following is copied verbatim from nView on-line help; the mode I 
> use is Dualview, which I believe is nVidia's default):

Well, I have an nVidia graphics card now, but you'll have to contribute 
to the fund to buy me a second matching Samsung SyncMaster 191T flat 
panel if you expect me to be able to work on this :)  At the momement 
(read: for the last three years) I have only one monitor.

Harold

Re: Configuration for multiple monitors

[Jack Tanner]

Øyvind Harboe wrote:
> perhaps the below should *always* be TRUE and there shouldn't be 
> an option at all?

No, I'd like -nomultiplemonitors to exist.

I have two monitors, but the second is usually turned off. Various X 
client dialog boxes and application windows usually come up in the 
center of my desktop, which means half on one monitor, and half on the 
other. If that weren't annoying enough, it makes life sheer hell when 
one monitor is turned off!

This is why I do not use -multiplemonitors, even though I /have/ 
multiple monitors. Even when both monitors are turned on, it's plenty to 
have one for X apps, and another for regular Windows apps.

Granted, the real solution to this issue would be to play nice with 
nVidia's nView software. It offers these modes for dual-monitor work 
(the following is copied verbatim from nView on-line help; the mode I 
use is Dualview, which I believe is nVidia's default):

Single Display. Only one of your connected displays is used.

Clone. Both displays in the display pair show images of the same desktop.

Horizontal Span. Both displays in the display pair behave as one wide 
virtual desktop. The width of each display is half the width of the 
total virtual desktop width.

Vertical Span. Both displays in the display pair behave as one tall 
virtual desktop. The height of each display is half the heiht of the 
total virtual desktop height.

Dualview. Both displays in the display pair behave as one virtual 
desktop. Unlike Horizontal or Vertical Spanning mode, Dualview treats 
ach display as a separate device. This means that the task bar will not 
be stretched across displays and 3D applications are not accelerated as 
efficiently if the application Spans displays.

-JT

Re: Configuration for multiple monitors

[Øyvind Harboe]

Harold,

perhaps the below should *always* be TRUE and there shouldn't be 
an option at all?

g_ScreenInfo[i].fMultipleMonitors = TRUE;

If so, then the changes TBD are:

- remove the -multiplemontiors option
- always set fMultipleMonitors=TRUE, or remove fMultipleMontiors altogether.

(Code removed is not code deleted; it is in CVS in case it needs to be summoned 
at some point.)


Thanks for these tips BTW:

http://www.cygwin.com/ml/cygwin-xfree/2004-01/msg00160.html

Øyvind