Adjust touchscreen coordinates for 4:3 aspect ratio on a 16:10 screen

bodiesofeverest · 07-12-2019, 01:52 PM

Hello I have kind of a weird device I've been working on lately. It is a tablet that has a native resolution of 800x1280, yes it is backwards. The display is in portrait mode and I have to make some xorg config edit to rotate the screen and rotate the touchscreen. This works great if I use the native resolution, however I am trying to get it to use a 768x1024 resolution. I have succeeded in getting the 768x1024 resolution in 4:3 mode (with black bars on the side, which is what I want) to show on the tablet by using these commands:

Code:

user1:~ # xrandr --newmode "768x1024_60.00"   65.25  768 816 896 1024  1024 1027 1037 1063 -hsync +vsync
user1:~ # xrandr --addmode DSI-1 768x1024_60.00
user1:~ # xrandr -s 768x1024_60.00

What I'm having trouble with is getting the actual touchscreen digitizer to align with it. Here are my xorg config files:

Code:

user1:~ # cat /etc/X11/xorg.conf.d/99-touchscreen.conf
Section "InputClass"
        Identifier "evdev touchscreen catchall"
        MatchIsTouchscreen "on"
        MatchDevicePath "/dev/input/event*"
        Driver "evdev"
        Option "SwapAxes" "true"
        Option "InvertY" "true"
EndSection

Code:

user1:~ # cat /etc/X11/xorg.conf.d/50-monitor.conf
Section "Monitor"
    Identifier "DSI-1"
    Option "Rotate" "right"
EndSection

mrmazda · 07-13-2019, 12:39 PM

Why are you mixing xrandr with xorg.conf*? Try using only one or the other. In *xorg.conf*, along with Rotate, use Horizsync, VertRefresh, PreferredMode and Section "InputClass" instead of xrandr modelines. Xorg computes modelines automatically when presented with appropriate specifications.

Shadow_7 · 07-14-2019, 02:38 AM

$ x11-touchscreen-calibrator

$ xinput_calibrator

The later I've actually used (long ago on a pocketchip).