libXrender - documentation?

[Charles Lindsey]

In <FE028D69955796489B510CE43DBBE803112CD7A9 at rrsmsx503.amr.corp.intel.com> "Wichmann, Mats D" <mats.d.wichmann at intel.com> writes:

>It seems that a library providing an API ought to have docs,
>even if the main consumer is another library.  That way the
>producer/consumer relationship is codified and there's
>actually something to refer to if one or the other changes.

Absolutely so. The main reason people might need it, even if they were not
toolkit developers, is so that they could trace apparent bugs or other
misfeatures that they had encountered in some application.

In my case, I was looking for some unacceptable CPU usage in Opera, which
is built on top of QT. I traced that down to a bug/misfeature in libxft,
which I reported on this list on Nov 26th under the Subject "LibXft :
xftglyphcore woes", hoping to catch the eye of the libxft developers
(sadly, noone responded). Essentially, libxft was making a meal out of its
anti-aliasing, and I proposed a patch which at least cured the symptoms.

In a subsequent thread "2D antialiasing?" on this list, I was bemoaning
the fact that antialiasing by that method would waste huge amounts of
bandwidth if the client were separated from the Xserver by some slow
network, and someone claimed to me, offlist, that Xrender provided
server-side antialiasing.

So I wanted to verify that claim. Now that this list has pointed me to
Keith Packard's "The X Rendering Extension", I have done a quick scan of
that, but can still find no mention of antialiasing. Moreover, that
describes the protocol, rather than the libXrender interface that is more
conveniently used to access it,

>Xrender is in LSB, but is not documented.  As a result,
>LSB would be willing to help if there's interest in working
>up docs.  Or, alternatively, listen to an argument that a
>library like Xrender actually shouldn't be in the spec, that
>only cairo should be exposed.

Yes, that would be welcome, but this is not really a Linux problem. It is
an Xorg problem.

-- 
Charles H. Lindsey ---------At Home, doing my own thing------------------------
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