[Fontconfig] Font matching in Unicode locales

[Ambrose Li]

On Sun, Oct 26, 2003 at 07:42:16AM -0800, Keith Packard wrote:

> > And not all traditional Chinese fonts support the bulk of
> > Big5; decorative fonts may support only the "frequently
> > used characters", i.e., the first 5401/13051 = 41% of
> > the original Big5 space, a lot of these aren't even Han
> > characters; I believe this would make fontconfig conclude
> > that such fonts do not support Chinese.
>
> Insomuch as they can't really be used to correctly display
> nearly all documents, this statement is true.  Much as many
> decorative Latin fonts include only upper case, you wouldn't
> want one of them picked to present messages to the user.

Theoretically this is correct and makes perfect sense. However,
I would reason that beyond a certain percentage of incomplete
coverage (perhaps with the additional condition that a font must
completely cover the first 5401 characters in Big5, and perhaps
only if the FreeType backend is being used), a font should be
considered "supports Chinese" even though it does not cover all
13051 glyphs in Big5.

Revisiting the "sans" family: Even in Microsoft Windows, there
is *no* free (in whatever sense) sans font covering all of Big5
(unless you only use Windows 2000 or later, in which case you
have "SimSun"). Instead, an augmented GB2312 font, "MS Hei",
is used for the "sans" font for traditional Chinese. This is
despite the fact that "MS Hei" cannot display "nearly all
documents" encoded in Big5.

(On GNU/Linux systems, AR PL KaiTiM Big5 is often mapped as
"sans". Typographically speaking, this is wrong, though in
practice probably nothing better could be done; the "kai" family
is a stylized calligraphic type, which when mapped to Western
typographic terminology should strictly speaking be classed as
"italic" [cursive forms deriving from stylized handwriting, not
necessarily slanted per se].)

Or perhaps there should be a property specifying that a font
"most likely will support" a given language. I don't know if I
am making sense here.

-- 
Ambrose LI Cheuk-Wing  <a.c.li at ieee.org>

http://ada.dhs.org/~acli/