[XForms] Shared GL contexts

[Angus Leeming]

On Thursday 27 May 2004 11:13 pm, Angus Leeming wrote:
> Unfortuanately, I managed to shut down X11 when I exited from the
> demo. It doesn't do this everytime, but most definitely did do it
> once.

It's actually very easy to do this.

$ cd xforms/devel
$ cd build
$ make maintainer-clean
$ cd ..
$ rm -rf build
$ patch -p0 < shared_gl_canvas.diff
$ ./autogen.sh
$ mkdir build && cd build
$ ../configure --enable-demos
$ make

demos/sgl is the statically-linked executable. There's also a dynamically-linked 
executable hidden away in the demos/.libs directory. Now, the dynamically-linked 
executable isn't going to run as things stand, because the installed libformsGL.so
doesn't contain the new functions. So, let's use the statically linked one.

$ ./sgl

The app pops up as expected. At this point, I'm going to save the mail in the 
expectation of crashing X. I'll return with the prescription...

... returning having crashed X, here's the prescription:

If the 8 sub windows are labelled so:
	1 2 3 4
	5 6 7 8

Then I can crash X reproducibly by clicking on the buttons:
	3:Visible   --- hide sub window 3.
	2:B		--- the object changes to a cone
	2:B		-- the object disappears from sub windows 1 and 2.
	2:C		-- usually there is no apparent change. Occasionally X crashes.
	Exit		-- X *always* crashes.

Here I'm running a linux box with a stock Fedora Core 1 distribution.

Angus