Hans,

Thank you for your suggestion. I tried disabling all otf features except
besub, but it didn't work. I presume that prepend should be added like this:

\startluacode
fonts.handlers.otf.addfeature {
name = "besub",
type = "substitution",
prepend = true,
data = {
["uni0431"] = "uni0431.SRB.alt"
}
}
\stopluacode

BTW, I'm using LMTX Context version 2022.01.21 20:13. Should I send you
some files for diagnostics?

On Wed, Feb 23, 2022 at 12:00 AM Hans Hagen via ntg-context <
ntg-context@ntg.nl> wrote:

> On 2/19/2022 4:59 PM, Stefan Nedeljkovic via ntg-context wrote:
> > Dear list,
> >
> > I'm using the typeface Neacademia Text, and I'm trying to configure it
> > to the specifics of the Serbian language. I want to replace the usual
> > form of the lowercase cyrillic letter BE with the traditional Serbian
> > form. I opened the font file in Font Forge and looked up the glyph info.
> > Here is what I tried and what failed:
> >
> > \startluacode
> > fonts.handlers.otf.addfeature {
> > name = "besub",
> > type = "substitution",
> > data = {
> > ["uni0431"] = "uni0431.SRB.alt"
> > }
> > }
> > \stopluacode
> >
> > \definefontfeature[default]
> >    [mode=node,kern=yes,
> >    liga=yes,dlig=yes,
> >    calt=yes,ss03=yes,
> >    case=yes,ccmp=yes,
> >    locl=yes,script=cyrl,language=srb,
> >    besub=yes]
> >
> > No luck using hex codes either:
> >
> > \startluacode
> > fonts.handlers.otf.addfeature {
> > name = "besub",
> > type = "substitution",
> > data = {
> > [0x1ab] = 0x3f8
> > }
> > }
> > \stopluacode"uni0431"
> >
> > Interestingly the single substitutions from page 175 of the fonts manual
> > seem to work just fine.
> > Any help is appreciated.
> hard to say but you enabel quite some features so probably uni0431 is
> already replaced .. maybe
>
>      prepend = true,
>
> helps
>
> -----------------------------------------------------------------
>                                            Hans Hagen | PRAGMA ADE
>                Ridderstraat 27 | 8061 GH Hasselt | The Netherlands
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