Bug 1169828

I used a script for two years (at least) to get 1920x1080 screen on a 1366x768 native LCD laptop using intel driver. This allowed me to work in full hd screen without problem.

It just stopped working.

the script I used is:

xrandr --newmode "1920x1080_60.00"  173.00  1920 2048 2248 2576  1080 1083 1088 1120 -hsync +vsync
xrandr  --addmode VIRTUAL1 1920x1080_60.00
xrandr --fb 1920x1080_60.00 --dpi 96 --output eDP-1 --pos 0x0 --scale-from 1920x1080 --same-as VIRTUAL1

the display name can be  eDP-1 or eDP1 (without -), depending of the number of screen attached. Here it's with only the internal lcd.

the two first lines works as expected: the new mode is created as well as VIRTUAL1 (may need a change in xorg.conf to allow VITUAL1).

the third line used to works, giving full screen display. Now it don't anymore, simply reduce the display sizer to part of the screen, so it's the end of the line (--scale-from 1920x1080 --same-as VIRTUAL1) that don't works.

I suspect some xorg update, may be a bug fix, because this behavior is obviously a trick. But it allows me to have a much better living, on a 15.5" display, full HD is necessary.

logs (in Xorg.0.log) are (notice that to get this I had to plug in an other monitor, as the config become very unstable if I keep using my script):

[  4750.824] randr: falling back to unsynchronized pixmap sharing
[  4750.824] randr: failed to set shadow slave pixmap
[  4750.824] (II) intel(G0): switch to mode 1920x1080 on VIRTUAL1, position (1920, 0), rotation normal, reflection none
[  4773.617] randr: falling back to unsynchronized pixmap sharing
[  4773.619] (II) intel(G0): switch to mode 1366x768@60.1 on eDP1 using pipe 0, position (1920, 0), rotation normal, reflection none

this is an asus n550JK computer, optimus one, but with no nvidia driver, not even bumblebee - this part never worked, so full nouveau driver