Mirroring touch interface on 5" HDMI screen

I was able to get a 5" HDMI screen similar to the Kuman screen working with the aml-s905x-cc and was able to rotate the display 180 degrees but the touch UI has been more challenging. Without rotating the display the touch UI was rotated but with display rotation the y axis is mirrored. I attempted to change this with cooridinate transformation matrix controls:

xinput set-prop “ADS7846 Touchscreen” ‘Coordinate Transformation Matrix’ -1 0 1 1 1 0 0 0 1

When I mirror or alter the x axis that works as expected but when I try to mirror Y it isn’t mapping correctly. Any suggestions?

There should be a tool that generates the transformation matrix. It basically displays some points and you have to point at them. Then dump the transformation matrix.

Thanks, I don’t know of a tool and am following the general instructions for touch control rotation on linux- Is there a search term I am missing for such a tool?

I also found that if I do not rotate the screen with xrandr I can correctly map the touch to the display by using the invert x matrix, but if I rotate the display none of the matrices work. I have found some references to different matrices being needed if the display is rotate but I can’t figure out what should be used.

https://manpages.ubuntu.com/manpages/focal/man1/x11-touchscreen-calibrator.1.html

Don’t double post for the same thing.