Re: U+180A Nirugu

On Tue, 27 Oct 2015 13:18:20 +0000
Greg Eck <greck@postone.net> wrote:

> Hi Andrew,
> 
> Thanks for that helpful information. I know that the U+180A Nirugu
> does not function correctly in the final position - at least. I have
> tried to implement the Nirugu Final in the past and failed. So, it
> would seem that possibly the punctuation feature is at least one of
> the culprits of the malfunctioning. I will try to test out the U+1807
> also and report back.

A good rendering engine for OpenType will refuse to select a final
form for NIRUGU on the basis of it being in final position.  The UCD
data file ArabicShaping.txt records it as having the value
'join_causing' for its Joining_Type, which means that characters on
either side of it might change shape, but it itself won't.  To get
NIRUGU to change shape in final position, its Joining_Type needs to be
changed to Dual_Joining.

I fear that renderers may hard-wire this property, rather than
getting if from their usual source of Unicode properties.

Richard.

Received on Wednesday, 28 October 2015 01:33:55 UTC