Re: GNOME font library RFC

[Liam Quin <liam holoweb net>]

Lauris Kaplinski wrote:
> On Sun, 28 May 2000, Nathan Hurst wrote:
[...]
>> Wouldn't a UR[LIN] be the simplest solution?
> 
> If done via URX-s, then fonts should be completely loaded into client
> memory,
[...]

Before starting to load fonts across the web, it's important to
consider copyrights and licences.  Just as the Gnome copyright is
important, so are font copyrights.

Most commercial fonts can't be embedded or used on more than five
CPUs without permission.

Font vendors *are* interested in ways to make it easier to connect
font users and their customers, but right now, type designers
generally sell their fonts for a living.  And they don't get rich :-)

Any scheme to distribute fonts over the net has to address this issue.
There were attempts to do that with the ISO Font Services mode, but
I am not aware of any implementations of that, and the standard is
not freely available.

Having said all that, I am extremely interested in any work to improve
the dismal state of typography in the X Windows Sysetm and software that
uses it.  Commercial software like Word Perfect and FrameMaker generally
has to reimplement client-side font technology from scratch.

The DSSSL specification has a few notes on internationalisation and
type that might be of interest, although it's not an easy document to
read.


As for fonts being in memory, Most commercial PostScript interpreters
use a glyph cache -- it's a set of (fontID, pixels-per-em, glyph) triples.
With a networked font server this could be filled asynchronously too,
after giving the server a hint about encoding and usage.  With Kanji
fonts being anywhere from five megabyets to 20 or more, you really
don't want to have to render the things if yo don't have to.

It's useful to be able to get metrics for glyphs without rendering them,
too -- a formatter might use the width information for copy-fitting
without actuallly rendering all of the text.  it's *certainly* useful
to be able to get metrics for just a few characters.  I wrote a file
browser once that did this, asking X for a font containing only the
glyphs it needed, for a huge performance increase.

Lee

-- 
Liam Quin - Barefoot in Toronto - liam@holoweb.net - http://www.holoweb.net/
Ankh on irc.sorcery.net http://valinor.sorcery.net/
Co-author, The XML Specification Guide, Wiley, 1999
Forthcoming: The Open Source XML Database Toolkit