[luatex] How to access user-defined kerning

[Henri Menke]

On Fri, 2018-04-20 at 08:39 +0200, Hans Hagen wrote:
> On 4/20/2018 8:24 AM, Henri Menke wrote:
> > 
> > On Fri, 2018-04-20 at 07:47 +0200, Herbert Voss wrote:
> > > 
> > > Am 20.04.2018 um 05:52 schrieb Henri Menke:
> > > 
> > > > 
> > > > 
> > > > I'm trying to determine the kerning between two letters (here A and V).
> > > >  For
> > > > the
> > > > sake of this example I'm inserting negative kerning of -400/1000 em.
> > > >   However,
> > > > when I examine the kern in the kerning callback this massive enhancement
> > > > of
> > > > the
> > > > negative kern doesn't show up but I only see the kerning from the font
> > > > itself.
> > > > 
> > > > How can I access the user-defined kerns?  MWE is below.
> > > no problem with
> > No, that is not my problem.  The kern is correct in the output.  However, I
> > cannot inspect the kern from within the "kerning" callback.  The user-
> > defined
> > kern is not added inside the kerning callback and I want to know how to
> > query it
> > (see the line annotated with <--).
> the kerning and ligaturing callbacks are for text (an deven then only 
> make sense for traditional fonts with a kern and ligature table)
> 
> rendering math is done completely different and is a two pass process; 
> there are often two code paths, one for traditonal math and one for 
> opentype and opentype
> 

Could it be that you replied to the wrong thread?  There is no math in this
example.

> kerning/glueing there is done based on character classes, math 
> parameters and specific font information (the initial math list is more 
> complex than a textual node list)
> 
> eventualy the typoeset math becomes a sequence of regular nodes injected 
> in the list that makes a paragraph
> 
> Hans
> 
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