[NTG-context] weird behavior of font.feature.effect

[Wolfgang Schuster]

Sylvain Hubert schrieb am 08.11.2020 um 13:02:
> On Sun, 8 Nov 2020 at 11:24, Pablo Rodriguez <oinos at gmx.es 
> <mailto:oinos at gmx.es>> wrote:
> 
>     Hi Sylvain,
> 
>     this is the same as:
> 
>        \definefontfamily[face1][rm][gabriola]
> 
>     Just in case, "slanted" is an already defined feature. It slants the
>     font.
> 
>      >     \definefontfamily[face2][rm][gabriola][it={features:{default,
>      > effect={}}}]
>      >     \definefontfamily[face3][rm][gabriola][it={features:{default,
>      > effect={width=1.0}}}]
> 
>     BTW, the documentation is clear
>     (http://texdoc.net/texmf-dist/doc/context/presentations/bachotex/2018/bachotex-2018-fonteffects.pdf#search=fontfeature):
>     font features should be defined as such before being deployed.
> 
>      > Could someone explain:
> 
>     I will try from what I understand.
> 
>      > 1. What does "effect" mean?
> 
>     A ConTeXt (and not OpenType) font feature?
> 
>      > Why does "effect={}" embolden the fonts even though nothing ({}) is
>      > given as arguments?
>     "effect={}" may be reading default values (it might be intended behavior
>     or not).
> 
>     But it also could be reading or calculating from previously defined
>     values.
> 
>      > 2. Similarly, what does "width" do? Why does "width=1.0" shrink the
>      > width of the line instead of doing nothing?
> 
>     This might be a bug, because of all the code improvements.
> 
>     I’m reporting a proper bug.
> 
> 
> Thank you very much for the explanation and the bug report!
> 
> Just in case it helps: the line shrinking disappears with an additional 
> "delta=0":
> 
>      \definefontfamily[face3][rm][gabriola][it={features:{default, 
> effect={width=1.0, delta=0}}}]


Don't set the values within \definefontfamily:

\definefontfeature [myfeature] [effect={width=1.0, delta=0}]

\definefontfamily[face3][rm][gabriola][it={features:{default,myfeature}}]

Wolfgang