[cgmo-webcgm] Style properties: text font

[Dieter Weidenbruck <dieter@itedo.com>]

All,

I saw comments spread in various emails regarding text font, e.g.

> >text-font: (gone?)
>
> I hope so.


As far as I remember, text-font has been on the list of requirements
from the beginning on, and I wouldn't like to take it off now.

There are several use cases, where changing the text font is very helpful:

- Display of CGM if used font is not installed
A viewer could use a default font, however, depending on the script system,
this will not lead to reliable results. Consider English/French/German text
on a CGM displayed in Japan: the default font there would not be able to
display a lot of the characters.

- Legacy issues
We have to consider the cases where "old" non-WebCGM files are used in our
environment. The consequences are well known from the ATA GREXCHANGE
experiences.
There are tons of CGMs out there with font names like "C12" or similar,
and the users are not allowed to change them. Being able to set an
appropriate
font inside a viewing application is very helpful.

In IsoView, we have been using font mapping tables for most of this, a
heavily
used feature. The text-font style property is nothing but the attempt to
standardize
this functionality.

Regards,
Dieter