Re: Font dependencies

[David Holland <dholland-pkgusers%netbsd.org@localhost>]

On Wed, Jun 20, 2012 at 05:23:37PM -0500, Tim Larson wrote:
 > > That's more or less what I meant - but there should be a way for a
 > > package to be able to express that it needs a Hebrew font or whatever.
 > > Having it pick *which* such font you want is obviously wrong.
 > 
 > True.  Hmmm.  I can't think of a way, offhand, to express that in
 > pkgsrc as-is.  Maybe with some more thought?

"I think we may need more infrastructure to handle them properly"

 > > There should also be at least one font meta-package that installs decent
 > > basic fonts for all alphabets.
 > 
 > A meta-package per "alphabet", pointing at a Free font that
 > provides full (or the fullest available) coverage for that
 > alphabet, might not be a bad idea.  A meta-package for "all
 > alphabets" would point at these, in turn.  Which font to use is
 > open to discussion, of course.

I was thinking that one meta-package would be enough; people who
wanted to know what the recommended default Thai font is could look at
the meta-package contents and then install the font they wanted
directly.

 > I would put forth that a good metric might be, use the font that
 > fully covers the most alphabets, so that at the end of the day the
 > least amount of time and space is used for the installation.  If we
 > are concerned with 50 alphabets, and there's a font that fully
 > covers 40 of them, that's a good candidate to choose.

Well... no, I don't think we should default to a low-quality font just
because it has wide coverage. For any particular alphabet we should
pick a font that won't embarrass the project.

 > These meta-packages might have a list of all fonts (in pkgsrc) that
 > do provide full coverage of the alphabet in question, so that if
 > one that is not the "top choice" IS installed, the meta-package is
 > satisfied and does not try to install anything.  Obviously this
 > would need care and maintenance from typeface geeks.  Possibly some
 > tool could be written to auto-update this font coverage info
 > whenever a font package is added/changed/removed.

We do have alternatives logic built into the depends system, so in
theory one could have a package called e.g. any-hebrew-font that
depended on one expression containing all the available such fonts as
alternatives. But this expression would be horrific where lots of
fonts are available, such as for latin1.

I was thinking it would want to be some mechanism like requires/
provides, as in "this package provides (a) font(s) for: greek" and
"this package requires a font for: greek".

But then, it's also not really alphabets as such either, it's glyph
sets, and even if we assume that this can be adequately expressed as
subranges of the Unicode glyph space (which is not necessarily the
case) there are a lot of complications that might appear. What about,
e.g. cyrillic fonts that don't include the letters used only in
Ukrainian? I'm sure some of these exist as relics of the Soviet era.

There's nothing easy about proper i18n unfortunately...

-- 
David A. Holland
dholland%netbsd.org@localhost