Nice layout for showing free keys

[dbr]

Nice UI for showing assigned keys:

http://tech-artists.org/forum/showthread.php?3060-PyQt-Dynamic-Hotkey-assignment-tool-for-Nuke

[herronelou]

I'm interested in trying to implement the visual part of this and started doing some research (posting some for further reference).
The code for the above is mostly available at: https://github.com/hslth/NukeHotKey/tree/master/step4

I'd want to support multiple keyboard layouts and found that a lot of the mappings for different keyboards can be found here: https://github.com/unicode-org/cldr/tree/release-42/keyboards

And there are good references here:
http://kbdlayout.info/
http://www.keyboard-layout-editor.com/ < Sadly layouts don't map to the ISO values above, but to a generic QWERTY?