Re: Screen all blank?

[Owen Taylor <otaylor redhat com>]

On Sat, 2009-01-24 at 12:37 -0500, Yu Feng wrote:
> On Sat, 2009-01-24 at 12:25 -0500, Owen Taylor wrote:
> > On Fri, 2009-01-23 at 22:30 -0500, Yu Feng wrote:
> > > Hi all;
> > > 
> > > I installed gnome-shell with jhbuild along the steps on the wiki; then
> > > started the shell with scripts/start-in-Xephyr.
> > > 
> > > But apparently I am getting a huge blank pixmap with these debugging
> > > informations on the console:
> > > 
> > > Warning: Cannot convert string "xlogo32" to type Pixmap
> > >     JS ERROR: !!!   Exception was: Error: No JS module 'signals' found in search path
> > >     JS ERROR: !!!     lineNumber = '0'
> > >     JS ERROR: !!!     fileName = 'gjs_throw'
> > >     JS ERROR: !!!     stack = 'Error("No JS module 'signals' found in search path")@:0
> > > ("No JS module 'signals' found in search path")@gjs_throw:0
> > > @/home/rainwoodman/gnome-shell/source/gnome-shell/js/ui/main.js:6
> > 
> > This is probably why you are getting the blank output.. if
> > initialization of the Javascript code fails, nothing much will show up.
> > Why this is, I have less of an idea. signals is shipped along with gjs.
> > Does:
> > 
> >  ~/gnome-shell/install/share/gjs-1.0/signals.js
> > 
> > Exist?
> > 
> > > Window manager warning: Log level 16: NOTE: Not using GLX TFP!
> > 
> > This is normal for start-in-Xepyhr. This certainly needs to be fixed to
> > warn only once.
> > 
> > > I was building at rev 164.
> > > And the computer is sort of old with a radeon R200 or R100 card:
> > > 01:00.0 VGA compatible controller: ATI Technologies Inc Radeon Mobility
> > > M7 LW [Radeon Mobility 7500];
> > > I am no 3D folk but compiz works (though pretty sluggish) on the card.
> > 
> > An R100. I expect performance to about like compiz - not pleasant to
> > use, but should come up. Amount of video memory matters quite a bit. In
> > any case, I think your problem is the Javascript error.
> > 
> Indeed. After switching to a jhbuild shell the signals become happy.

I keep on wondering whether start-[replace/in-Xephyr] should check if
they are running under jhbuild and if not either:

 - Error out
 - Automatically add the 'jhbuild run' themselves

I've avoided that because eventually as dependencies and in
distributions we might support hacking on metacity with a
system-installed mutter. But for now we probably do one of the above.
Since jhbuild is the only way of running gnome-shell that I'm willing to
support at the moment.

Usually without jhbuild you get something a little more interpretable.
Along the lines of:
 
 metacity error: option --mutter-plugins not recognized

> Are there any catch/try mechanism or global flag to let gjs ignore the
> fatals? 

It's a very good idea that the shell should just exit if running the
Javascript initialization fails, rather than leaving things running with
a messed up display.

> BTW: if librsvg is not found, the script also terminates with '.svg'
> file not recognized.

If the librsvg gdk-pixbuf loader is missing?

- Owen