Don't get too carried away, the iTextSharp port will still have to work and
there's no layoutGlyphs() there. I'm also a bit worried about the behavior of
different java versions when layoutGlyphs() is all that is used for rendering
ligatures. The correct way would be to use the GSUB and other tables in the
font and solve all the script problems that way, including the Indic scripts.
Paulo
> -----Original Message-----
> From: Robert Muir [mailto:[email protected]]
> Sent: Wednesday, April 08, 2009 2:08 PM
> To: itext-questions
> Subject: [iText-questions] question about glyph positioning
>
> Hello,
>
> I sent a simple patch to get things moving with complex
> scripts (indic languages) but to get it really correct
> (example: Urdu language in Nastaliq script), some more things
> to be done.
>
> I've done most of the following to get this language going
> but its not ready yet:
>
> 1. Removal of ArabicLigaturizer/etc code. Instead, Arabic
> text is passed as-is to layoutGlyphs() which does this
> transparently. In some cases Arabic fonts do not have
> presentation forms and do this with opentype GSUB tables
> (http://partners.adobe.com/public/developer/opentype/index_tab
> le_formats1.html). Nastaliq fonts are a perfect example of
> this, as they have thousands of ligatures.
>
> 2. text does not need to be reordered by Bidi-Analysis prior
> to being laid out, however, the argument (RTL, LTR) for a run
> of text does need to be supplied to layoutGlyphs() to get the
> correct behavior. So Bidi Analysis is moved.
>
> 3. Remaining problem: need to take the vertical positional
> information from layoutGlyphs(), (derived from GPOS tables:
> http://partners.adobe.com/public/developer/opentype/index_tabl
> e_formats2.html) and put this in the PDF somehow. The figure
> referenced there
> (http://partners.adobe.com/public/developer/en/images/fig4b.gi
> f) shows what is currently displayed in PDFS for nastaliq
> font, "Incorrect".
>
> In problem #3 I need to apply some vertical position to an
> individual glyph... I'm looking at using
> PDFContentByte.setTextRise() which appears to be designed for
> subscript/superscript... is there a better way?
>
> --
> Robert Muir
> [email protected]
>
>
Aviso Legal:
Esta mensagem é destinada exclusivamente ao destinatário. Pode conter
informação confidencial ou legalmente protegida. A incorrecta transmissão desta
mensagem não significa a perca de confidencialidade. Se esta mensagem for
recebida por engano, por favor envie-a de volta para o remetente e apague-a do
seu sistema de imediato. É proibido a qualquer pessoa que não o destinatário de
usar, revelar ou distribuir qualquer parte desta mensagem.
Disclaimer:
This message is destined exclusively to the intended receiver. It may contain
confidential or legally protected information. The incorrect transmission of
this message does not mean the loss of its confidentiality. If this message is
received by mistake, please send it back to the sender and delete it from your
system immediately. It is forbidden to any person who is not the intended
receiver to use, distribute or copy any part of this message.
------------------------------------------------------------------------------
This SF.net email is sponsored by:
High Quality Requirements in a Collaborative Environment.
Download a free trial of Rational Requirements Composer Now!
http://p.sf.net/sfu/www-ibm-com
_______________________________________________
iText-questions mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/itext-questions
Buy the iText book: http://www.1t3xt.com/docs/book.php
