[gs-devel] PDF Formularies in Ghostscript

[Ray Johnston]

Dear Alberto,

Ghostscript previously did not view any AcroForm data, but this is 
partly implemented,
disabled unless -dShowAcroForm=true is specified. Ghostscript currently 
does not
do anything with the 'interactive' elements of PDF such as JavaScript 
viewing mods,
but an application can send PostScript strings to access elements from 
the PDF
such as fetching the JavaScript in order to process within your application.

For an example of PostScript that can dig information out of a PDF using
Ghostscript, please see toolbin/pdf_info.ps. You may also want to look at
the way Ghostscript gets the AcroForm dictionary in lib/pdf_main.ps and
how the data is processed in lib/pdf_draw.ps.

Note that since the AcroForm code is quite new, you will want to get the
latest source from svn (using: svn co http://svn.ghostscript.com/trunk/gs )
or wait for 8.57 (which is coming out very soon).

If you do decide to enhance Ghostscript to utilize the JavaScript code or
otherwise process and/or fill in the form data, we would be interested
in this for possible inclusion in the product since yours is not the first
time this has been requested.

If Ghostscript continues to interest you and you encounter problems or
questions, please feel free to contact us. We cannot guarantee how
much help we can provide for other than commercial customers, but
since the project is interesting we will try to assist.

Best Regards,
Ray Johnston
------------------------------------------------------------------------

alcueca wrote:
> Hello all, excuses if this information can be found on the documentation, the
> issue at hand is a bit complex and after some research is now when I think I
> could use some expert advice.
>
> I have a client which desires to code an open-source PDF viewer which would
> be able to display forms, allow the user to fill them, and run JavaScript
> validation tests on the introduced information.
>
> My company is first researching the feasibility and costs of such a project,
> and later we would be responsible for the development of the first
> prototype, the client would finish the development and carry the
> manteinance. We are looking for open-source pdf libraries and viewers which
> we could use or extend for this task.
>
> As far as I know, there are only three open-source libraries, which are the
> base for every open-source PDF viewer out there: Ghostscript, xpdf -
> poppler, and mupdf. I haven't seen any open-source pdf viewer which supports
> forms.
>
> The questions are:
>
> Are formularies supported by the ghostscript library?
> are they expected to be supported in near future?
> maybe any other of the libraries could be used for this end?
> Is there any open-source pdf viewer which supports forms?
>
> Thanks a lot for your attention, cheers,
> Alberto
>
>
> P.S: Excuse me for reposts, I received notifications from nabbler about the
> needing to subscribe and I'm not sure if the previous mail arrived.
>