Re: [g-a-devel]Ghost-View(ggv): Extracting text from GtkGs Widget

[Michael Meeks <michael ximian com>]

Hi Rajkumar,

On Thu, 2002-02-14 at 15:32, Rajkumar Sivasamy wrote:
> Am trying to implement accessibility for the "Ghost View Application"
> (ggv). For implementing accessibility for the view-port (Document
> displayed, & it's a GtkGs widget), we need to export the "Text" (text
> of document) to the AT. 
> 
> My Observations:
> (1) The display area is a GtkGs widget
> (2) The contents of the file ("*.ps") are extracted and passed to the
> "gs" through a socket.
> (3) From the line no. 970 in "gtkgs.c" which says:
>         "bytes_written=write(gs->interpreter_input,
> gs->input_buffer_ptr, gs->buffer_bytes_left)"
> I understand that the contents of file ("*.ps") is passed to the "gs" as
> such in the HEX Format.
> Is there any way to extract the text (Document's text) out from it ? 
> 
> Also it will be helpful if I get to know the encoding format of the text
> in postscript files.

	My feeling is that it is not possible to make GhostView accessible in
the way that has been suggested - like, really, really difficult.

	Parsing / understanding the streams that ggv can render is going to
require essentially a re-implementation of GhostScript outside the
engine - which is a total waste of time. Due to the way ggv works, it's
never going to be easy to do this.

	Not to be defeatist, but I really don't think you could make this fly
if you spent hundreds of man hours on it. If for some reason it was
decided that you should consume hundreds of man hours, I would recommend
that for PDF viewing you should look at using the 'xpdf' code as a base,
and writing a 'gnome-print' frontend for it to render (what is
essentially) postscript, since we have all that code in gnome-land
anyway. Of course, that leaves 'postscript' rendering in the dark, but
..

	Really - it's not an easy problem; there is so much else, that would be
much more useful that it's just not amusing; surely the base
AtkComponent support will allow some degree of magnifier usage of the
component - beyond that it gets very difficult indeed.

	Regards,

		Michael.

-- 
 mmeeks gnu org  <><, Pseudo Engineer, itinerant idiot