etx, mtx, texnansi, afm2pl

Siep siepo@cybercomm.nl
Fri, 12 Jul 2002 23:57:26 +0200


On Wed, 10 Jul 2002 21:27:23 +0200
Lars Hellstr  <Lars.Hellstrom@math.umu.se> wrote:

> At 15.08 +0200 2002-07-10, Siep wrote:
> >I am working on a utility afm2pl, an afm2tfm replacement,  which as
> >its default action produces a pl file with the original kerns and
> >ligatures preserved; see www.ntg.nl/afm2pl.html.
> 
> Why would you write such a thing? This is precisely what fontinst does[1]!
> Furthermore fontinst (unlike what appears to be the case with afm2pl) runs
> on any platform for which there is TeX (your afm2pl seem to require
> porting) since it is written in TeX.
> 
> [1] Fontinst keeps the ligature glyphs in the original font, but ignores
> the ligaturing instructions from the AFM file. What ligaturing instructions
> one wants depends on the other hand on which the target encoding is, which
> is why fontinst requires that ligaturing instructions are specified in the
> ETX files. The ligaturing instructions in AFM files are usually terribly
> insufficient for use with TeX.

The main reason is simplicity: with afm2pl and texnansi, you just
need to create a single tfm. The supporting files are also much
simpler and easier to understand.

afm2pl can and default does add TeX-specific ligatures. Ligature
handling is based on afm2tfm code, but ligkern specifications are
read from separate files. This is configurable from the
command-line.

> >I would like to add fontinst inputfiles for generation of smallcaps.
> 
> If you want to fake smallcaps then you need to make virtual fonts, i.e.,
> output a VPL in addition to the base PL.
> 
> If you mean "how much would I have to change an afm2pl that understands
> fontinst v1.8 files in order to have it understand v1.9 files" then the
> answer is "probably quite a lot", but that's not the whole story. Since
> fontinst files are TeX input, you would (to begin with) have to incorporate
> a fairly complete TeX parser in afm2pl to have it understand fontinst files
> for _any_ version. This is at least an order of magnitude greater than
> simply supporting the new features in v1.9.

I guess I didn't make my intentions entirely clear: I want
to complement afm2pl-generated non-virtual font metric files with
fontinst-generated font metric files for smallcaps. It seems I got
that worked out now.

Anyhow, thanks for your comments.

Siep