Re: [Indic-computing-users] help pfaedit

[Baiju M <ba...@fr...>]

>
> 1. we succeeded in doing ligature rules using pfaedit, but the problem
> is the last character gets repeated after producing the desired
> ligature. Why is this so? and how to avoid this.


Well now you added 'liga' feature tables (lookup type 4) too all
glyphs, so it should work in Yudit. Now dump this font into XML,
rest of things can be done in XML (use TTX). just changing the name
of 'liga' as 'akhn' (its for Akhand) (this is also lookup type 4) should
work in GTK+2.x appd (test it in gedit). But using 'akhn' for all glyphs
is bad idea, so you can increase number of features,

BTW, contextual sigle substitution is not working in Yudit
its working in GTK+ (You can use this for Devanagari vovel sign E,
but there is no seperate designs in Akruti devanagari font, so you can
leave this)

If you desided to add a new indic feature, increase ReqFeatureIndex like
this (in ScriptList):
<FeatureIndex index="0" value="0"/>
<FeatureIndex index="1" value="1"/>
.....................
....................

now change FeatureList like this :
<FeatureTag value="liga"/> to <FeatureTag value="akhn"/>
you can increase number of FeatureRecords as defined above (in ScriptList)
ang give appropriate names, for example 'pres' feature for Pre-Base
substitution.

Now Lookuplist (its will take time to edit)
add new Lookups here (as defined in the FeatureList),

<LookupList>
      <!-- LookupCount=1 -->
      <Lookup index="0">
        <LookupType value="4"/>
        <LookupFlag value="0"/>
        <!-- SubTableCount=1 -->
        <LigatureSubst index="0" Format="1">
          <LigatureSet glyph="uni0D15">
            <Ligature components="uni0D4D,uni0D31" glyph="glyph00248"/>
            <Ligature components="uni0D4D,uni0D33" glyph="glyph00238"/>


see this is a LookupType 4 ('liga','akhn' etc can use this)
the first one is unicode sequense of Malayalam KRA (it is
U0D15+U0D4D+U0D31) and glyph ID is glyph00248

yuo can refer to other freely available OTF fonts
(Kannada,Bangala,Malayalam etc.) for more deatils.


>
> 2. how to add gpos rules in pfaedit?  and how to define kern pairs using
> pfaedit?

Editing GPOS tables are very difficult, though you can do it manualy :(
kern pairs can be defined in PfaEdit (refer pfaedit manual)

Regards,
Baiju M