[cairo] configure errs in determing if xrender backend supported on RHE 2.1

[Carl Worth]

On Fri, 16 Apr 2004 16:50:41 -0600, Charles Tuckey wrote:
> This is a small thing. I am compiling cairo-0.1.21 on RHE 2.1 which has 
> a older version of Xrender that won't work with the cairo xlib surface.

Cairo indeed has code that will take advantage of a very recent Render
extension. However, it also has code to make the xlib surface backend
work even if the server has no Render extension available, (though that
code is currently slower than it needs to be).

There's even some code to let it use a slightly old Render extension
where it can and only fallback where it must. This code has probably not
been tested fully, so I'm sure it's broken somewhere. This case gets a
bit tricky and we may decide it's not worth it and just treat an old
Render as equivalent to no Render.

That said, all of the fallback code I just described is based on runtime
checks on the server capability. What we don't have yet is a
compile-time mechanism for disabling the Render code and using a
straight Xlib. We do have the more coarse-grained --disable-xlib, but
that's obviously not what you want.

So, you could just go get the latest version of Xrender from
freedesktop.org. It's a sinlg library and it should compile and install
just fine even if your server doesn't support everything. That would
then let you compile cairo, and it would fallback as necessary.

Or, someone could add a compile-time switch to disable the use of
Xrender.

-Carl