[gdm-list] GDM behavior on dual head config

[Frederic Muller <fredm gnome org>]

Hi!

I've been struggling getting this right for a few month now (it's 
obviously not vital) and I am wondering what I am doing wrong, or how 
it's supposed to work:

I use a dual head setup with 2 different resolutions monitors.

1. Without adding a xorg.conf file the higher resolution monitor appears 
in a very low resolution and that's unfortunately where my login box is. 
I've tried to switch it on the other monitor without any luck. In that 
configuration however the other screen is just an extension of the main 
screen and is empty (except for the wallpaper).

2. Adding a xorg.conf file in /etc/X11/xorg.conf.d/ specifying the exact 
resolution for that monitor I get both monitors in the proper resolution 
but then the 2 monitors get set in 'mirror' mode. Not having the same 
dimension the gnome-shell top bar then stops before the side of one of 
the 2 screens. (one monitor is 1200pixel wide, the other 1280).

I have attached the 2 xorg files (one of the monitor is in portrait mode 
forcing me to have a xorg file even in case 1, else the login box is 
tilted by 90°). .conf1 is for case 1 and .conf2 is for case 2.

This happens on the pieces of hardware I have been playing with. So it 
seems to be a stable behavior.

Thank you to let me know what I'm doing wrong or indicate what the 
expected behavior should be then.

Fred

Section "Monitor"
	Identifier	"HDMI-0" 
	ModelName	"DELL" 
	Option		"Primary" "yes"
EndSection

Section "Monitor" 
	Identifier	"DisplayPort-1" 
	ModelName	"AOD 36" 	
	Option		"Right" "HDMI-0" 	
	Option		"Rotate" "left" 
EndSection

Section "Monitor"
	Identifier	"HDMI-0" 
	ModelName	"DELL" 
	Option		"Primary" "yes"
EndSection

Section "Monitor" 
	Identifier	"DisplayPort-1" 
	ModelName	"AOD 36" 	
	Option		"Right" "HDMI-0" 	
	Option		"Rotate" "left" 
EndSection

Section "Screen"
	Identifier	"Screen1"
	Monitor		"DisplayPort-1"
	DefaultDepth	24
	SubSection "Display"
		Depth	24
		Modes	"1920x1200" "1024x768"
	EndSubSection
EndSection