Thumbing through the Gnome GTK Widget Repository, I found that someone has
already implemented pie menus for GTK. I'm still not sold on having pie
menus in GIMP, but at least it means that if we do find a way to make
useful pie menus, it won't take much work to implement them.
Hmm, maybe we could as an advanced option make the menu button on the
canvas's upper left corner be a pie menu, and make the menu items
completely configurable. I guess that could work.
Anyway, the URL is http://atrey.karlin.mff.cuni.cz/~0rfelyus/GtkPieMenu/
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