I am able to use xinerama in fvwm. I use this configuration:
XineramaPrimaryScreen 0
Xinerama on
Style * StartsOnScreen 0
I have two screens, an external VGA monitor with a resolution of 1280x1024, and the LCD with 1280x800. The final virtual desktop is 2560x1024. Therefore, there is a region in the 1280x800 LCD monitor lager than the visible area. You could:
b[/b] Move the mouse cursor towards the edges and scroll (“pan”) the display.
or
b [/b]“If you have display devices with different maximum resolutions you might desire a non-rectangular screen to avoid panning.” (Thomas Winischhofer site). This is achieved by the MergedNonRectangular option in xorg.conf.
I am having a very strange behaviour. When X starts, I get the b[/b] panning behaviour (xdm login screen). In this situation, when I maximise a window, it occupies the whole virtual desktop (both monitors). If I log into fvwm and exit, I am able to get b[/b] MergedNonRectangular option (the one I prefer, because maximised screens stay on one monitor). If I restart X (ctrl-backspace) I am in b[/b] behaviour again. The log file /var/log/Xorg.0.log does not change after exiting and entering back into fvwm.
I do not understand why entering and exiting fvwm could change how xinerama behaves. Any hints appreciated. Thanks!
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Info:
I have a SiS 771/671 PCIE card. I am using MergedFB and I have followed the indications in Thomas Winischhofer site. This is the device section of my /etc/X11/xorg.conf:
Section "Device"
Identifier "Device0"
Driver "sis"
VendorName "Silicon Integrated Systems [SiS]"
BoardName "771/671 PCIE VGA Display Adapter"
BusID "PCI:1:0:0"
Option "EnableSiSCtrl" "yes"
Option "DRI" "off"
Option "MergedFB" "auto"
Option "MetaModes" "1280x1024-1280x800 1280x1024+800x600 1280x800 800x600"
Option "MergedNonRectangular" "on"
Option "MergedDPI" "100 100"
EndSection
Edit: I solved this issue by commenting the Option “Xinerama” “true” in the Server flags section of xorg.conf.