[FriBidi] log2vis() misbehaving with Arabic text?

[Behdad Esfahbod]

On 14-10-28 10:53 AM, Philip Semanchuk wrote:
> On Tue, Oct 28, 2014 at 1:18 PM, Behdad Esfahbod <behdad at behdad.org> wrote:
>> > On 14-10-28 10:09 AM, Philip Semanchuk wrote:
>>> >> I took your advice and tested U+200C in a PDF. Both Acrobat Reader and
>>> >> my default PDF reader (Preview -- I'm on OS X) render it as a vertical
>>> >> bar. That a surprise; I thought it would either be invisible or render
>>> >> as the standard "unprintable character" rectangle.
>> >
>> > It's from a broken PDF generator.  The vertical bar is what "show format
>> > characters" in MS apps is supposed to show.  Ie, the font has that glyph, but
>> > the shaping engine (eg, part of what renders to PDF) should know not to show
>> > it normally.
> So you're saying that characters like U+200C and U+200D are like
> processing instructions to the PDF generator (reportlab, in this case)
> that should inform the text layout engine but should then be stripped?
> In other words, they should not appear in the generated .pdf file?

Yes.  Something in that line.  See third question here:

  http://www.unicode.org/faq/unsup_char.html

They should not *visibly* appear in the generated .pdf.  What that actually
means gets really technical.  But any way you can make them invisible is
probably a good solution.

-- 
behdad
http://behdad.org/