I was able to make my Synaptics touchpad absolute with this command:
xinput set-mode <device name> ABSOLUTE
<device name> is
"SynPS/2 Synaptics TouchPad" (including quotes). To find your device name, you can list your devices with the
xinput command and no options. Look for a "slave" device, which is the actual hardware, not the master device, which is virtual. I was not able to set my
"Virtual core pointer" to absolute, but I don't know about your
"eGalaxTouch Virtual Device".
For me, the upper and lower bounds of the touchpad didn't quite reach the upper and lower bounds of the screen, but left and right were correct. So you might have to adjust a scaling factor or coordinate transformation matrix or some such. You can view your device properties with this:
xinput list-props <device name>
and set a property with this:
xinput set-prop <device> <property> <val>
Check the xinput man page for more info on setting properties.
I don't know if there is a way to put these settings in your
xorg.conf file, but you can simply add the commands to your
~/.xinitrc file. See
How to create an X session script.