Question about dual monitors

[Karl Auer]

On Sat, 2006-04-22 at 00:06 +0100, Daniel Carrera wrote:
> How is X.org or Xinerama supposed to know which one is supposed to be 
> the LCD screen on my laptop and which one is the CRT connected to the 
> VGA output?

Because in the screen section you say what monitor to use and what
device it is attached to. A screen is a monitor attached to a device.
And in the device section you number the screens. If you aren't doing
all that, do do it :-)

Below is a dual-head setup for an ATI Radeon, where you can see this
happening. Note that I've removed everything else, so it can't work as
ist, it's just to show the device/monitor/screen/layout relationships.

Regards, K.

Section "Device"
	Identifier	"ATI_0"
	Driver		"radeon"
	BusID		"PCI:1:0:0"
	Screen		0
EndSection

Section "Device"
	Identifier	"ATI_1"
	Driver		"radeon"
	BusID		"PCI:1:0:0"
	Screen		1
EndSection

Section "Monitor"
	Identifier	"Laptop monitor"
	Option		"DPMS"
EndSection

Section "Monitor"
	Identifier	"External monitor"
	Option		"DPMS"
EndSection

Section "Screen"
	Identifier	"Laptop Screen"
	Device		"ATI_0"
	Monitor		"Laptop monitor"
EndSection

Section "Screen"
	Identifier	"External screen"
	Device		"ATI_1"
	Monitor		"External monitor"
EndSection

Section "ServerLayout"
        Identifier      "DualHead Layout"
        Screen          0 "Laptop Screen" 0 0
        Screen          1 "External Screen" RightOf "Laptop Screen"
	Option          "Xinerama" "on"
EndSection


-- 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Karl Auer (kauer at biplane.com.au)                   +61-2-64957160 (w/h)
http://www.biplane.com.au/~kauer/                  +61-428-957160 (mob)