Created attachment 151213 [details]
screenshot showing how tablet area is mapped in exisiting kcm

SUMMARY
The recent feature addition to new graphic tablet kcm under Wayland is awesome and a huge relief. However currently it lacks an option to select a portion of the tablet surface to map that area to the screen [monitor] area. User can draw a custom area currently but this is for selecting the portion of the screen and not the tablet. While selecting a portion of the are of screen to limit tablet input to that area is good. Majority of users would choose to select a position of the tablet surface to map it to entire screen. A use case for this is user having a large non graphic tablet (the non display one) and wanting to use only a portion of the tablet surface for the screen.

STEPS TO REPRODUCE
1. Boot into neon unstable under wayland and go to tablet section in the system settings
2. try to select an are of the tablet to map it to entire screen. There is custom area but it only allows users to select the screen are and not the tablet area.


OBSERVED RESULT
No way to visually select tablet surface area to map it to entire screen

EXPECTED RESULT
User should be shown a graphic of the tablet currently they are using and a way to draw and select area of the tablet surface to map it to entire screen.

I am attaching a screenshot of the existing tablet KCM under xorg to show how it is achieved in it.