they use the dejavu and freesans font, too.... afaik
see this (from wesnoth's fonts.cfg)
[fonts]
# This is marked as translatable, to allow translators to
# provide different font orders: one just has to install the
# missing fonts without needing to change the gmo files
order=_ "DejaVuSans.ttf,FreeSans.ttf,sazanami-gothic.ttf,gkai00mp.ttf"
this seem to change font by .mo file.
in fact, wesnoth's .pot contain "order=_ "DejaVuSans.ttf,FreeSans.ttf,sazanami-gothic.ttf,gkai00mp.ttf""
lines.
by the way, sazanami-gothic.ttf is free japanese fonts.
but not gpled.
this is sazanami-fonts lisence.
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