Re: Optical size information in Emmentaler-nn OpenType fonts

[Urs Liska]

Hi Werner,
thanks for the thoughts

Am 08.09.2012 08:47, schrieb Werner LEMBERG:
> > I have an Adobe OpenType font family containing its font faces in
> > four sets: text, caption, subhead and display, each set designed for
> > use at different point sizes.  I assume the different Emmentaler-nn
> > fonts serve the same purpose.
> Sort of, yes.
>
> > If I use this Adobe font with LaTeX and fontspec it selects the
> > right font automatically depending on the point size.  [...]  I
> > opened both fonts with FontForge but didn't find a setting that
> > seems responsible, and I don't really know anything about the inner
> > workings of OpenType (or any) font technologies.
> Aah.  Look up the `size' feature on this page:
>
>    http://www.microsoft.com/typography/otspec/features_pt.htm
>
> I wasn't aware that such a feature exists.  The necessary information
> could be rather easily added using FontForge, I think.  Your request
> definitely deserves a new issue in our tracker. :-)
>
> > Would it make sense to add this?
> Yes.  Unfortunately, it seems that Pango doesn't support this
> currently out of the box (I've just asked on the gtk-i18n-list to be
> sure) which means that lilypond doesn't directly benefit.

Well, I'm not sure about that anymore.
The feature makes sense if you have several variants of the same family, 
and these variants are designed to be used at different point sizes.
What I'm now starting to doubt is that you can have this relation 
between font version and point size in our case. Which one would be the 
suitable Emmentaler version for a particular point size (in continuous 
text of another font)? I don't think there is  a useful relation.
For my purpose (embedding Emmentaler in continuous LaTeX text) it seems 
to make more sense to conceive the different .otf versions as 'weights' 
that could be made selectable (maybe s.th. like 1 through 7, 
corresponding to Emmentaler-26 to 11). This will be implemented either 
as an option for the commands or as a command to change weight somewhere 
in the document.

So please excuse the noise.

Best
Urs
>      Werner