Re: GSoC 2020 update, May 30

[Werner LEMBERG]

> I started work on Han-Wen's suggested order of operations. In order
> to make the .mf files output a SMuFL code to their log, I needed to
> learn Metafont, which proved to be a language as little documented
> as it is ingenious.  [...]

In case you have TeXLive installed, simply type

  texdoc metapost

to get a nice and short introduction into METAPOST (this is what we
actually use to generate the fonts instead of METAFONT).

> (I had to use strings because MF doesn't support numbers at/above
> 4096.)

This is not true for (recent versions of) METAPOST, which supports
various number systems, including IEEE 64bit floating point.  However,
to still allow processing with METAFONT to generate the nice DVI glyph
previews, such code should be restricted so that it is executed for
METAPOST only.  Note that selecting the number system is a run-time
option (see appendix A); if you really need large integers, the build
system of LilyPond has to be updated accordingly (and probably the
minimum version of METAPOST, too).

> As an aside, looking at my Git history, it appears that, when I
> tried to change the name of my first commit to be more informative,
> I accidentally fused it with Valentin's previous commit.  [...]

Don't worry.  For GSoC purposes I strongly suggest that, shortly
before the end, you create another branch that contains your stuff in
concise, small, and logically ordered commits so that reviewers can
easily follow.


    Werner


PS: A remark to Freetype versions: I think you can safely assume that
    FreeType 2.6 and newer is available.  There is other code in
    LilyPond that could be simplified if this assumption is true, and
    I will eventually submit a Merge Request to handle that.