Re: [gtk-i18n-list] Which Non-Latin Scripts Do Free Software Fonts Not Cover?

[mpsuzuki hiroshima-u ac jp]

Hi,

On Wed, 17 Oct 2007 00:02:18 +0100
"Dave Crossland" <dave lab6 com> wrote:
>Are there non-latin scripts that free software fonts do not cover at
>all at the moment?

Excuse me, you are asking about "there are proprietary fonts
for the script, but no free fonts for the script"? Or,
you are asking about "a script without any existing fonts"?
If former, please clarify the license you recognize as free.
For example, "Open Font License" is free in your context?

>Are some scripts supported by Pango better than others?

It's difficult question, I think. There are 2 kinds of
mechanisms to support a script by Pango: one is based
on OpenType technology, and another is based on legacy
encoding (I mean, non-Unicode) in the fonts designed
before OpenType (you can find some bits in Thai modules
of Pango).

The code for 2nd mechanism is not growing anymore.
In fact, some of these are already removed (e.g. there
had ever been Indic support by legacy encoding).

Growing is the 1st mechanism. But, the 1st mechanism
is based on OpenType technology which the specification
of script support is defined by Microsoft. Please check:
	http://www.microsoft.com/typography/SpecificationsOverview.mspx
You can find a list of scripts which Microsoft supports
officially, in Script-specific Development. If a script
is not listed here but requires special complex text layout,
the script is not supported by "official" OpenType specification.

A typical example might be N'Ko script. Pango already
includes a module to layout N'Ko script by OpenType font.
But Microsoft does not provide any specification for OpenType
table design to support N'Ko script. So, there is a
possibility that Microsoft can define incompatible "official"
N'Ko support in future and "official" N'Ko fonts doesn't
work well with current Pango implementation (and current
N'Ko OpenType fonts doesn't work well in future Microsoft
products). ICU does not support N'Ko script yet by such
reason, please check:
	http://bugs.icu-project.org/trac/ticket/5865
How do you think of?

>Are there any scripts which Pango does not support well or at all?

Some slightly-minor scripts that requires complex
text layout features are not supported yet, I guess.
For example, Limbu is an Indic script but current
Indic module does not support Limbu (basic module
is assigned to the script). There is a free-charged
font including Limbu is existing (damase_v.2.ttf),
but there's no OpenType support to tune the position
of multiple vowel signs, so it does not display the
ligature shown in the end of Table 10-5 in Unicode
5.0 p. 362, I guess.

But, I'm afraid, if you choose such script as your target,
your precious time will be spent for contacting native
users or linguistic experts, than for typographic works.
Do you want to concentrate yourself to typography?

# In Japan, there were several academic projects to develop
# fonts and text rendering system for various Asian scripts
# (arabic & indic variants) before Unicode popularization,
# but the speed of projects had a bottle neck in the
# difficulty of communication between Japanese students in
# font production and native users of the scripts, I heard.

Regards,
mpsuzuki