Wacom Cintiq calibration tool may appear on the wrong monitor
The Wacom Tablet section of the GNOME Control Center displays a "Calibrate" button for Cintiqs and other display tablets. Clicking this button pops up a full-screen calibration tool which has you click on the center of various targets. The UI must appear on the Cintiq's own display to be useful, but it may appear on the wrong display in some circumstances.
I noticed this while implementing a fix for mutter#1889 (closed). With the fix applied the pen would be mapped to the Cintiq display but the calibration tool would appear on my secondary monitor. Digging in further, I believe the cause is a lack of communication between Mutter and G-C-C. The calibration code inside of G-C-C has a function to determine the monitor based on EDID information saved in dconf, but Mutter has its own logic to determine what monitor a pointer should be mapped to which does not set that EDID information. I believe that the "best" solution would have G-C-C query Mutter's mapping functions (e.g. meta_input_mapper_get_device_logical_monitor()
) since setting the EDID can have undesirable side-effects (e.g. "stuck" bad mappings).
Steps to reproduce:
- Connect a Cintiq and a second display to your system
- Depending on the exact setup (e.g. display sizes, tablet used, etc.) G-C-C and Mutter may choose different displays to map the stylus to and display the calibration screen on