Re: [Indlinux-group] Re: devanagari ctl with xft enabled mozilla

[Dhananjay J. <ds...@bu...>]

Hello,

Prabhat Hegde wrote:

> thanks for sending. I've been aware of this.
>
> I think its a good idea. However some considerations i had a few years 
> when i first integrated pangolite are still relevant i think.
>
>    1. Pango is too heavy to carry around.
>    2. Much more tricky to support edit operations.
>    3. Also, mozilla already uses a different code-path for Arabic
>       shaping which means that we should place great emphasis on
>       making API light-weight.
>    4. How about non-gtk/non-pango Unix support
>
> with regards,
> prabhat
>
> Pango is too heavy to carry around.

In what sense? If you are talking about function overheads then, in this 
module we are calling only low level pango interface like pango itemize 
and pango shape besides that there are no calls to function calls to 
pango higher level interfaces. Plus in creating this module I have used 
your ILE/ULE component as a template so any overheads with respect to 
XPCOM are going to be same.

> # Much more tricky to support edit operations.

can't really comment on that, since I have not tried it yet.

> # Also, mozilla already uses a different code-path for Arabic shaping 
> which means that we should place great emphasis on making API 
> light-weight.

we are not really interested in creating a new api, just using the 
functionalities of the api already available and widely used and also 
avoid code-duplication. What I believe is that these different codepaths 
for bidi were made earlier when pango was not yet a mature 
application/dev library. Plus the only code I have changed in the base 
mozilla code is adding a function for creating the DrawString Specs. 
using the glyphs recieved from the module (and even that is a 
copy/re-implementation of the original code with very minor 
modifications.  besides adding a few kb to the size of the concerned 
binary, It is not going to have any performance penalties.

> How about non-gtk

pango has no dependencies on gtk. for example
pkg-config --cflags --libs pango
-I/usr/include/pango-1.0 -I/usr/include/glib-2.0 
-I/usr/lib/glib-2.0/include  -Wl,--export-dynamic -lpango-1.0 
-lgobject-2.0 -lgmodule-2.0 -ldl -lglib-2.0

other pango packages like pangox, pangoxft and pangoft2 use the system 
specific libraries x,ft2 and xft respectively in addition to the ones 
mentioned above
I am using pangoxft

>    4. non-pango Unix support
>
we just want users to have option to use system installed library much 
like (--enable-system-zlib). they can always stick to the pango lite 
support if they want.
The functionality provided by your code is not changed in way. This 
component totally bypasses it.

regards,

dsjoshi