My letter to a fellow developer in a discussion about free Chinese font license technicalities.

font

[snipped]

In fact we are also running into this problem in our own game, 
about the "partially embedded" font. And as I dug deeper into this, 
I only see more and more restrictions.

For now, I can only say that all freely-available Chinese fonts 
I have researched are at least restricted by GPL, and actually 
there are only 2 of them available (though they have different 
font faces and weights in their font family):
WenQuanYi: http://wenq.org
WangTTF: http://apt.nc.hcc.edu.tw/pub/FreeSoftware/free_fonts/wangttf/

But only WenQuanYi has added the "Font Exception" part to its 
GPL License, to prevent "the inclusion of unaltered portions" 
of the font make the document/program become GPL infected:
http://en.wikipedia.org/wiki/GPL_font_exception

And rasterized glyph-altas / font bitmaps are considered to be 
"unaltered portions." They actually prevent you from altering/deriving 
from the original font itself, it will be a violation to the license 
or you have to be GPL infected.

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Just some thought to discuss. I originally thought using fonts 
available on one's developing machine, and make font bitmaps 
out of those, only for glyphs we actually needed, is generally OK. 
But from what I learned today, I think it is at least disputable 
if not violating the font's license. Unless its made into a part of 
other art works, like UI button textures or logos, and no individual 
glyphs can be trivially extracted (be it vector data or bitmap data).

Also, there are just so many fonts with obscure licenses and 
some of them even don't have a license to be found, 
therefore no way to be sure. 

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