[poppler] Wrong Unicode mapping of the Omega symbol

[Albert Astals Cid]

El Dijous, 9 d'agost de 2012, a les 13:30:50, 王璐 va escriure:
> Hello,
> 
>   I've got a pdf created by LaTeX, with special fonts for maths.

Can you please create a bug in bugs.freedesktop.org and attach that file?

This way we'll include it in our regression tests and make sure it does not 
regress when we change something else.

Cheers,
  Albert

>   There are chars named Omega, which can be displayed correctly according
> to the font (also with the Omega slot).
> 
>   I'm now working on a project called pdf2htmlEX, I need to map chars to
> "meaningful" Unicodes for text selection, meanwhile the fonts should also
> be remapped.
>   In my case, the fonts are remapped with Fontforge, where Omega is mapped
> to the correct Unicode value; but poppler didn't, in the final HTML, the
> symbol was not displayed with the font math, as the symbol cannot be found
> in the font.
> 
>    I think pdftohtml in poppler will also suffer from this problem when
> font embedding is implemented.
> 
>    I've found more references:
> 
> http://en.wikipedia.org/wiki/Ohm#cite_note-2
> http://www.unicode.org/versions/Unicode4.0.0/ch07.pdf#search=%22character%20
> U%2B2126%20maps%20OR%20map%20OR%20mapping%22
> 
>    So Ohm is is included for backward compatibility, and Omega is
> preferred. which means it'd be ok if both Ohm and Omega are mapped to
> 0x03A0. But we should never map Omega to 0x2126.
> 
> 
>   Thanks
> 
>    - Lu
>   2012.08.09
> 
> On Thu, Aug 9, 2012 at 6:29 AM, Albert Astals Cid <aacid at kde.org> wrote:
> > El Dijous, 9 d'agost de 2012, a les 00:04:51, 王璐 va escriure:
> > > Hi all,
> > 
> > Hi
> > 
> > >    In poppler/NameToUnicodeTable.h
> > >    
> > >    
> > >    Both Ohm and Omega are mapping to 0x2126, which is incorrect.
> > >    
> > >    Should be
> > >    
> > >    Ohm -> 0x2126
> > >    Omega -> 0x03A9
> > > 
> > >    Reference:
> > > http://www.fileformat.info/info/unicode/char/2126/index.htm
> > > http://www.fileformat.info/info/unicode/char/03a9/index.htm
> > > 
> > >    I wonder how this file was created, do we need to check other
> > >    symbols?
> > 
> > Ask the xpdf author (oh wait he won't answer)
> > 
> > Now bad jokes aside, do you have a pdf showing a problem because of this?
> > 
> > Cheers,
> > 
> >   Albert
> >   
> > >    Thanks
> > >    
> > >    - Lu
> > >    2012.08.09
> > 
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