Purpose of and rationale behind Go Markers U+2686 to U+2689

[Garth Wallace]

On Thu, Mar 17, 2016 at 11:28 PM, J Decker <d3ck0r at gmail.com> wrote:
> On Thu, Mar 17, 2016 at 9:18 PM, Garth Wallace <gwalla at gmail.com> wrote:
>> There's another strategy for dealing with enclosed numbers, which is
>> taken by the font Quivira in its PUA: encoding separate
>> left-half-circle-enclosed and right-half-circle-enclosed digits. This
>> would require 20 characters to cover the double digit range 00–99.
>> Enclosed three digit numbers would require an additional 30 for left,
>> center, and right thirds, though it may be possible to reuse the left
>> and right half circle enclosed digits and assume that fonts will
>> provide left half-center third-right half ligatures (Quivira provides
>> "middle parts" though the result is a stadium instead of a true
>> circle). It should be possible to do the same for enclosed ideographic
>> numbers, I think.
>>
>> The problems I can see with this are confusability with the already
>> encoded atomic enclosed numbers, and breaking in vertical text.
>>
>
> I suppose that's why things like this happen in appilcations....
>
> Joined "ti" coded as "Ɵ" in PDF
>
> http://www.unicode.org/mail-arch/unicode-ml/y2016-m03/0084.html
>
> you get an encode of a series of  codepoints, that results in an array
> of font glyph-points to render ....

What?

I don't see what an apparent ligature matching or OCR glitch in PDFs
has to do with this.