How to change the orientation (rotate) of an HDMI output in WAYLAND on a raspberrypi

Question

I am building a kiosk application that is to run on a raspberry pi 4. The linux system was built using buildroot. The display server is WESTON, which is an implementation of Wayland.

My application needs the output to be displayed on tv screen in the potrait position.

Reading the docs for WAYLAND, i have included the followin snippet in my "weston.ini" configuration file

[output]
name=HDMI-A-1
transform=90

However, WESTON fails to launch with the error message in the log file saying:

Invalid transform "90" for output HDMI-A-1

Setting "transform=normal", WESTON launches successfully and displays in landscape form.

I'm i missing an extra step in building weston?

Any hints and suggestions are highly welcome Regards

Answer 1

try

[output]
name=HDMI-A-1
transform=rotate-90

This is what I use in my pinball project

BTW, is there way to enumerate outputs names before starting weston ?