Re: Indic scripts

On Tue, 2004-06-01 at 09:59 +1000, msevior@physics.unimelb.edu.au wrote:
> >
>
> Hi Sayamindu,
> Thank you very much for your offer of help. Please feel free
> to ask questions here and on the #abiword IRC channel.

Thanks for the encouragement :).

>
> Are you more comfortable developing for Wndows or Linux? In the case of
> Windows Tomas Frydrych has done a lot of work to use the native windows
> script rendering library.

I don't have Windows in my box :).

>
> On linux we'd like to use pango to do the same thing but no one has yet
> had time to develop it.
>
> Look in src/af/gr/xp/gr_Graphics* and src/af/gr/unix/gr_UnixGraphics* or
> src/af/gr/win/gr_Win32Graphics

I had a quick look at the code - look like one possible way would be
modify GR_UnixGraphics::drawChars to use the xft backend of Pango
(http://developer.gnome.org/doc/API/2.4/pango/pango-Xft-Fonts-and-Rendering.html).
Of course, others things such the line width calculation stuff, cursor
positioning, etc will need to be changed too - but once you have got the
basic rendering in place - the rest should be comparatively easy
(hopefully). Of course, getting printing to work will be another major
PITA, but at this stage getting on screen rendering would be a major
step forward.

Just for fun, I cooked up some ugly hacks to convert pChars to a
PangoGlyphString - and then used pango_xft_render () to render it
onscreen - and got some interesting results.
A major problem however, is to convert m_pXftFontD to PangoFont - and I
simply have no clue on how to do this.

-thanks-
Sayamindu

PS: if anyone is interested - the modified file is at
http://sayamindu.randomink.org/misc/gr_UnixGraphics.cpp
Please - please - do remember that the hacks in there are extremely ugly
(done in five minutes) and don't even try to look at them if your temper
tends to flare up very easily. Of course - you are free to use the file
as a shining example of how not to code ;).

PS (again): I have no idea on this - but can IBM ICU be used in any way
to do the rendering ? Some quick 'n dirty information is available at
http://oss.software.ibm.com/icu/userguide/layoutEngine.html

-- 
Sayamindu Dasgupta
[http://sayamindu.randomink.org/ramblings]