[NTG-context] Harfbuzz plugin and colors

[Hans Hagen]

On 2/14/2022 3:47 AM, Jairo A. del Rio via ntg-context wrote:
> Hi, list! I've tested the Harfbuzz plugin in ConTeXt and it works nicely 
> for most cases. However, color doesn't seem to work. Is this intended? I 
> know this plugin won't be supported, but I'll be fine with pointers to 
> solve this issue. Thanks in advance.
> 
> \usemodule[fonts-plugins]
> \definefontfeature[harf]
>    [mode=plug,
>     features=harfbuzz,
>     shaper=native]
> %Just to test Harfbuzz is actually working
> \definefontfeature[devaA][harf]
>    [language=dflt,
>     script=deva]
> \definefontfeature[devaB][default]
>    [script=deva]
> \definefontfeature[colored][harf]
>    [language=dflt,script=arab,
>     colr=yes] %doesn't do anything
> \startbuffer[hindi]
i honestely have no clue if color will work (also because hb is in a 
sort of continuous flux wrt updates and so, and i tend not to update 
libraries without knowing why) .. as long as there is nothing needed 
that is handled by node mode such things should work

keep in mind that this is just there because idris and i wanted to 
compare the output different rendering approaches (on windows one can 
use the uniscribe mode and uniscribe is sort of the reference so in case 
of doubt we try to follow that) but i haven't looked at if for years

using that plugin is it's a bit of a gamble wrt what features to enable 
adn what heuristics kick in, but you can try at least to enable arabic

\definefontfeature[colored][arabic,harf]
    [language=dflt,script=arab,
     colr=yes] %doesn't do anything

however, it looks like i have to itercept a default color (doesn't 
relate to plugins) so i'll send you the one-line patch for that (at 
least in node mode that works)

Hans


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