[cairo] [Xcb] cairo + xcb binaries

[Behdad Esfahbod]

Bernie Innocenti wrote:
> Cross posting to the cairo list.
> 
> Matthew Allen wrote:
>> I'm currently implementing a xcb + pango + cairo backend for a
>> widget library and I'm having issues getting the xcb part of
>> cairo working. Basically the function cairo_xcb_surface_create
>> doesn't exist in the headers (and the libs as well). From what
>> I read you have to --enable-xcb when you install it. However I
>> want to be able to make binaries of my apps that just run on
>> current distros. Am I facing a dead end because the distros
>> don't compile in xcb support?
> 
> FWIW, Fedora is not enabling the xcb backend because apparently it
> changes the ABI of libcairo.so:
> 
>   https://bugzilla.redhat.com/show_bug.cgi?id=465759
> 
> This prevents the window manager Awesome from appearing in Fedora 10.
>  Ubuntu Intrepid has it though, and seems to ship an XCB enabled
> version of Cairo.

If anyone has a vested interest in cairo-xcb, they would first need to help us
get it on par with the xlib backend and add a way to keep it there.  One way
to do that is to merge the two backends.  We considered that and had a Summer
of Code student to work on it.  Unfortunately nothing came out of it.

Until that happens, using cairo-xcb instead of cairo-xlib is a regression.
It's not really about whether we do that --enable-xcb or we don't.  cairo-xcb
is inferior to cairo-xlib.  That's all.

behdad


>> My impression was that people wanted to move more stuff towards
>> xcb and away from xlib? Aren't the major widget sets doing that?
>> So if thats the case, how to the distros gets away with not
>> compiling in xcb support in cairo?
> 
> I don't see a big rush to XCB among the toolkit folks yet.
> 
> Maybe some benchmarks showing how XCB would improve throughput or
> latency would help convince people?  If there's any evidence you could
> share, I'd be interested in
> seeing them.
> 
> For now, most distros ship an XCB enabled version of libX11, which
> made some things slightly slower, iirc.  A comparison against new
> version of libX11 would be a bit unfair.
> 
> 
>> I'm running ubuntu 7.04 at the moment. But I don't mind targeting
>> later builds if necessary.
> 
> If you're working with bleeding edge technology, you might want a
> bleeding edge distro shipping the latest upstream releases of Cairo
> and XCB.
>