I'm looking for a way to display the current keyboard layout chart from the command line.

Unfortunately xkbprint does not display utf-8 characters correctly (AFAICT).

In gnome, it is possible to click on the keyboard layout indicator applet and then "Show Layout Chart", which does the same thing as going through the menus of gnome-control-center (btw, gnome-control-center keyboard is not an acceptable solution), so there must be a way to trigger an event that would pop up this window, right?

Note that most of the time I don't use gnome-panel.