Arabic OpenType kerning

Arabic OpenType kerning

[Khaled Hosny]

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Kerning doesn't seem to work with TRT direction, in the attached axample
(using the attached font), enabling kerning with TRT direction inserts
positive kern between first kern pair and nothing between the rest (it
should be negative kern). With TLT direction kerning seem to be fine.
Using \kern primitive seems to work fine too.

Regards,
 Khaled

-- 
 Khaled Hosny
 Arabic localiser and member of Arabeyes.org team
 Free font developer

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\definefontfeature	[kacst]
			[mode=node,language=dflt,script=arab,
			 init=yes,medi=yes,fina=yes,isol=yes,
			 liga=yes,mark=yes,mkmk=yes]

\definefontfeature	[kacst-kern][kacst][kern=yes]
\font\nokern=KacstOne.ttf*kacst at 80pt
\font\yeskern=KacstOne.ttf*kacst-kern at 80pt

\starttext
\startTEXpage
\nokern\textdir TRT
صرصرصرصر
\stopTEXpage
\startTEXpage
\yeskern\textdir TRT
صرصرصرصر
\stopTEXpage
\startTEXpage
\yeskern
صرصرصرصر
\stopTEXpage
%\showotfcomposition{KacstOne.ttf*nokern}{-1}{صرصرصرصر}
%\showotfcomposition{KacstOne.ttf*yeskern}{-1}{صرصرصرصر}
%\showotfcomposition{KacstOne.ttf*yeskern}{1}{صرصرصرصر}
\stoptext

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Re: Arabic OpenType kerning

[Hans Hagen]

Khaled Hosny wrote:
> Kerning doesn't seem to work with TRT direction, in the attached axample
> (using the attached font), enabling kerning with TRT direction inserts
> positive kern between first kern pair and nothing between the rest (it
> should be negative kern). With TLT direction kerning seem to be fine.
> Using \kern primitive seems to work fine too.

hm, i can get it working but it needs some carfuel checking with idris' 
test collection


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___________________________________________________________________________________
If your question is of interest to others as well, please add an entry to the Wiki!

maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context
webpage  : http://www.pragma-ade.nl / http://tex.aanhet.net
archive  : https://foundry.supelec.fr/projects/contextrev/
wiki     : http://contextgarden.net
___________________________________________________________________________________