Re: Change kerning between math characters (prime and left parenthesis)

["Mikael P. Sundqvist" <mickep@gmail.com>]

On Fri, Jun 2, 2017 at 4:24 PM, Hans Hagen <pragma@wxs.nl> wrote:
> On 6/2/2017 10:59 AM, Mikael P. Sundqvist wrote:
>>
>> Hi!
>>
>> Now that the bug with primes is fixed in ConTeXt, I wonder if there is
>> a way to change the kerning between certain characters in mathematics
>> (in case one is not happy with the output from the font)? After
>> reading in fonts-mkiv.pdf this is what I came up with:
>
>
> you can also play withj:
>
> return {
>     name = "cambria-math",
>     mathematics = {
>        kerns = {
>           [0x1D453] = {
>               force = true,
>               topright = {
>                   {
>                       kern = 1000,
>                   },
>               },
>               bottomright = {
>                   {
>                       kern = 1000,
>                   },
>               },
>           },
>       },
>     },
> }
>
> currently you need to enable this:
>
> \enabledirectives[fontgoodies.mathkerning]
>
> keep in mind that some cambria (not all) have such staircase kerns which is
> why force is needed in order to overload
>
>> \startluacode
>> fonts.handlers.otf.addfeature {
>> name = "kerntest",
>> type = "kern",
>> data = {
>> [0x61] = { [0x62] = -150 }, -- a and b in text
>> [0x1d44e] = { [0x1d44f] = -150 }, -- mathematical italic small a and b
>> [0x02032] = { [0x00028] = -150 }, -- prime and left parenthesis
>> }
>> }
>> \stopluacode
>>
>> \definefontfeature[kerntest][kerntest=yes]
>>
>> \definefontfamily[lucidaopentype][rm][Lucida Bright OT]
>> \definefontfamily[lucidaopentype][mm][Lucida Bright Math OT]
>>
>> \setupbodyfont[lucidaopentype,10pt]
>>
>>
>> \startTEXpage[offset=3pt]
>> abba $abba f'(x)$
>>
>> \addff{kerntest}
>>
>> abba $abba f'(x)$
>>
>> I prefer $f'\mkern-3mu(x)$
>> \stopTEXpage
>>
>> The output is attached as a png file. As you see the kerning works as
>> expected in text mode, but not at all in math mode, even not for the a
>> and b (which I hope I entered correctly).
>>
>> Something like the third line is what I'm after, but not having to use
>> \mkern in all places. Is it possible?
>>
>> /Mikael
>>
>> PS: This is a cross post of the question
>> https://tex.stackexchange.com/q/372857/52406, where I got the
>> suggestion to ask on the list.
>>
>>
>>
>>
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>> ___________________________________________________________________________________
>>
>
>
> --
>
> -----------------------------------------------------------------
>                                           Hans Hagen | PRAGMA ADE
>               Ridderstraat 27 | 8061 GH Hasselt | The Netherlands
>        tel: 038 477 53 69 | www.pragma-ade.nl | www.pragma-pod.nl
> -----------------------------------------------------------------
>
> ___________________________________________________________________________________
> If your question is of interest to others as well, please add an entry to
> the Wiki!
>
> maillist : ntg-context@ntg.nl /
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> ___________________________________________________________________________________

Thank you Hans, that works.

Is there also a similar way to use the "kernpairs" instead of "kerns"?
I get no effect, even after adding force = true and
\enabledirectives[fontgoodies.mathkerning].

/Mikael
___________________________________________________________________________________
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maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context
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