aKademy [3] – DevConf – second day.

David Faure and Till Adam
The second day of DevConf begun with Aaron
Seigo and Waldo Bastian
teaching us mere geeks how to properly promote our applications.
Although it beared some elements of the motivation talk by some well-known big software vendor
company, known from movies on the internet (“developers, developers, developers, developers,
developers …”) it was quite funny. Nothing really new, nothing earth shuddering.

Short thereafter, I gained a lot of insight in KDE’s bindings through Richard
‘s talk about them, he elaborated on misconceptions, techniques to generate them, what’s
possible, what’s even much more easy using bindings rather than C++ (DCOP anyone?). Interesting, at
the very least.

I spent the afternoon, writing a basic PyQt Tutorial which took most of my attention, with a
short interruption to have a look at the KDE4 iconset “Oxygen” which is developed by Kenneth
Wimer, Nuno Pinheiro and David Vignoni
our divine artists. (I’ll not show photo’s of it, though.
You’ll have to wait. :P)

aKademy [2] – DevConf – first day.

David Faure and Till Adam
The first day of DevConf started with Multimedia API for KDE 4 by Matthias
who has done quite a lot of work on the kdemm API, a unified way to develop applications
that use multimedia. He was already able to show a basic application using the new framework which
is supposed to be used by KDE4.

Next were two talks about parallel execution, the first, Asynchronous Programming with Qt –
Pitfalls and Techniques
by Till Adam
and David Faure
showed a couple of techniques with which you can workaround the need for
multithreading, showing how to use QTimers and a couple of other techniques. In the second talk, Mirko
showed a structured approach to multithreading using interdependant threadlists and
adding dependancies to them. Pretty neat stuff, although Qt seemed not quite ready for all that.
(Mirko explicitely warned to *not* try this in Qt3.)

‘s eyecandy-wanking has been postponed to wednesday because the beamer doesn’t seem to like
Zack’s Mac, let’s hope this will get fixed. Zack did show his work later this afternoon, here’s a movie of it. Note that this is quite
an old notebook, about 4 years old, running XGl on a Radeon 9000 graphics card (!).

Aaron showed a couple of nice features of Qt4 designer, which does offer some new
stuff, such as easier integration of custom C++ widgets, it would be nice if that would be available
from python at some point, too. (But then PyQt4 is still far away.) Dragging and dropping and the
whole handling of layouts have undergone some major changes, which is quite good. There are still
some painting issues, though, but it seemed far better than what I’m experiencing with Qt3

Here’s an overview of the photos.

aKademy [1] – Social Event.

Party at el Liceo
Spanish food can be very unixy.

Not knowing the language, and most of the spanish people not speaking english very well
(“aah leetul”) makes it a pretty funny experience to order food. Tapas are a nice thing
then, you can basically order half of the menu and then pick the stuff you like. Someone will
probably eat the rest. Having small portions, which combine quite well is great.

The social event last night, which was kindly sponsored by Novell was a lot of fun as most
people attending aKademy will know. I’ve annoyed people walking around taking photos, have a look here.

aKademy [0] – UserConf day 1.

Conference Hall
After having had a lazy week in Javea, in the east of Spain, where Nel, Christine’s mother has
been a great host, I arrived in Malaga with a slight delay (thanks, Iberia).

Having gone to bed quite early, I was quite fit to begin the first day [schedule]. We were welcomed by people of
the Andalusian government, the university of Malaga and the people of the Malaga Linux group.

The technical part started with a presentation by Pete Goodall
who would give an overview over the Novell Linux Desktop. Quite obviously, not
everyone was impressed. The software used on the desktop is quite old (running KDE 3.2). Also, Pete
showed a KDE desktop and didn’t make to clear that the standard Novell Desktop is gnome-based. The
rest of the talk wasn’t also to developer-directed, ow well …

Far more interesting was Till Adam’s
talk, who showed off kolab and kontact, the KDE approach to groupware. Pretty fun,
lots of cool features coming up, such as a webclient (which needs more developers, PHP horde people
might be welcome there!). Kolab stores all kind of information in IMAP accounts, which makes it
possible to use a couple of groupware stuff (shared calendars anyone?) with any simple IMAP server.
Kolab however adds management interfaces, user management via LDAP and loads of other stuff.

from Canonical, the Ubuntu sponsors also did a very nice talk about
collaboration in the Open Source world. He talked about collaborated distributed
working, realtime collaborative editing (imagine working on the same document, at the same time,
discussing what you’re chaning …).

At the moment (uploading the blog might take some time, I forgot my wireless adapter at the
residence), I’m listening to Kurt
mind blowing presentation, demoeing NX technology. It’s far more
efficient than standard X11, as he and Fabian just showed by running an xnest session and a freenx
session in parallel and then increasing the lag on the localhost interface artificially. Nice.

… Kurt’s talk is finished, I got hold of a UTP cable and a dhcp lease and am uploading a
couple of photos now, enjoy
Aah … some sponsored social event for tonight has just been announced, is that the free
part? :-)

update: Yeah, free drinks.

The talks of Richard Moore
about Scripting with
KDE feel
was quite interesting, especially for the power user who wants to enhance his desktop

Also Will
had some interesting news to tell, skype integration into kopete being one of them.


Pommodori bread
I bake my own bread.

Normal dutch bread is pretty “fluffy” and light, it’s very easy
to compress but I like heavier bread much more. German bread is usually much heavier, and that’s
what I’ve grown up with.

Solution to the problem was the breadbaking machine I got from my mother, and I’m using it
pretty often, at least once a week. The fun thing is that this machine promotes creativity, plain
bread is easy to make, but it’s just as easy to put some other ingredients into it. My lasts breads
have been bacon bread (baked bacon in it, perfect match with cheese), fruitbread
(dried fruit, such as apple, apricots, prumes, best with plain butter), onion bread
(with fried onions in it, tastes good with everything except sweeter stuff, cheese does very
good, so does bacon). Today I visited the St. Annamolen, a clichee dutch mill where they’re actually
still milling. You can buy all sorts of flours right there, and they seem specialized in providing
bread mixes for bread machines. (And also pet supplies, hi Rinse.) They have about 40 different
sorts of bread mix there, I’ve chosen the “Pommodori bread”, which gave a really good
result, red bread with a strong taste of tomatoes, obviously.

It can be quite tricky to produce a good dough. The right amount of water is crucial, but the
amount of salt and sugar in your ingredients can have a lot of influence, too. Salt makes the yeast
rise less, sugar has the opposite effect. A good measure of thumb is that the dough should be a
little sticky. Well, it’s a science, but recent results show I’m advancing (ask [ade], he serves as some sort of Guinea pig for some
of the experiments). The fun part was trying to get an idea of the effect of sugar, when the dough
found its way outside the bread machine, cleaning the mess afterwards was less fun, though.

Friday, I’ll be leaving for Spain, where I’ll visit a friend near Alicante and head for aKademy about one week later. I’m preparing for the trip
which is finishing my paper, do other paperwork which otherwise might need attention through the
next two weeks, get notebook prepared for all kinds of conference stuff and hacking, wash clothes,
think about the content of my luggage, prepare list of people which I owe a beer… In short boring
and stressful.

I’m looking forward to meeting you in Málaga!

kde and powermanagement.

guidance's DPMS settings
One of my special interests is power management (PM).

While discussing if a display powermanagement option really should be in guidance‘s displayconfig, I had a look where
PM-related options are living in kcontrol at the moment.
It was quite a shocking experience.

Assuming I want to optimize my laptop for battery lifetime, where are the places I have to go in
kcontrol, what assumption do I have to understand? Let’s have a look.

  • display power management comes to my mind, go to Peripherals -> Display -> Power
  • Most WiFi card drivers offer a powe saving mode, go to Internet & Network ->
    Wireless Network
  • Power Control -> Laptop Battery offers actions for events when battery is
    running out and also some ACPI controls which make suspend modes and CPU power saving modes
    available – if setup correctly, also there’s a battery monitor
  • My installation also has modules for IBM Thinkpad laptops (mostly for buttons / ACPI
    events) and a Sony VAIO module which aims to make the battery status of two batteries available (I
    have neither of those models, so these modules are of no use for me.)

I think the most easy thing for the novice user with respect to getting the laptop draining less
power is getting hopelessly lost.

The solution to this problem, however, is not trivial. Power management is related to a lot of
different areas, suspend modes such as suspend-to-ram, suspend-to-disk, power management of
different devices such as wireless adapters and the display play a role, but there’s obviously more
to it. I encountered that when designing the display powermanagement tab for guidance’s
displayconfig. It seems related to a screensaver (although a screensaver is no more than some eye
candy toy on more recent hardware), but DPMS is some sort of extreme screensaver. Then there’s CPU
states (C1 through C4 on some systems, although that’s really nothing the user should ever

The big question is: How can power management be handled in a sensible way?
That is without having duplicate configuration options.
The approach I’ve taken now in guidance
is offering a DPMS tab, mostly for practical reasons, with a button to configure the screensaver
which just starts the screensaver configuration module. I’m not sure if we’re going to keep it this
way, though.

If you’re also interested in this area, please drop me an e-mail at sebas@kde.nl. Maybe this
topic can also have profit by some discussion at aKademy
, which I’m going to attend.

back from Berlin.

Berlin, Reichstag
So obviously I’m back from my vacation and already had my first (quite productive) working day.
CodeYard‘s infrastructure is nearly completely in place now (thanks to [ade]), and I wrote down some stuff for EuroQUIS,
mostly theories related to software quality assurance. With Simon having working internet access
again, KDE related stuff seems to have advanced a bit. After returning I also found Debian packages
of guidance including dependancies in my
mailbox. Next step is to test, review and merge the stuff. It’s probably a good idea to include the
debian/ directory in our subversion repository, so it’s easy for people to build updated

My vacation (together with $GIRLFRIEND) was really good, Berlin is still a great city. Lots of
stuff to do, such as checking out all sorts of new architecture. What struck me was that the “new
centre”, around Potsdamer Platz (where Sony, Deutsche Bahn, Deutsche Telekom and other big
businesses built their vision of a metropole) does have pretty much no charme at all. Good place to
take photos, bad place to have fun. Far too much commercial stuff. Bummer.
Much more enjoyable is Kreuzberg, which grew into a really good place to eat (especially the
delicious breakfasts here). Also the people there are
pretty down to earth, very direct in their communication, still friendly in most situations. And
terrific Currywurst at the Curry 36, probably the best one in Germany.
We also visited Potsdam’s famous castle Sanssouci, which really looked like “old Fritz” wanted to banish normal
life and create a place free of sorrows. Nice walks in the park though.
Checkout a selection of my photos
taken during the trip
, partly even wallpaper material. :-)

twins arrived.

The twins
I received my new displays today. Finally I don’t use CRTs anymore, my Samsung Syncmaster 710N
and my Iiyama S900MT1 have been replaced by two Samsung 173P 17″ TFT displays. The colors
are very bright, the picture is crispy, and the design very stylish. The first thing I did was
setting all my fonts 2 points smaller. :> Another technical highlight of these screens is the great
contrast (1000:1). More pictures can be found somewhere in my gallery pages. Although
these displays are not designed for gamers (response time is around 25ms) they perform reasonably
well with respect to ghosting even with a fast first person shooter. (But then I’m not a gamer-type.)
The screens have one button to switch them on and off. Switching on and off is confirmed by a
subtle beep, the button reacts on a slight touch, nothing moving.

The rest of the functionality is supposed to be setup via software. Of course the software
Samsung distributes with the panels is non-free and Windows only, which is quite lame. (They could
at least support free software projects by releasing specification to make it easier to support all
the nifty features for Open Source software developers. *sigh*) Ddccontrol, however, can do most of the stuff (changing
settings) via DDC so it’s quite usable under Linux, which is my OS of choice. I didn’t find a way
yet to use the pivot feature (both screens can be rotated a full 360º) and XRandR’s rotation
stuff does not work in dualhead mode.
Not at least, these screens save a lot of enery compared to my old CRTs, which is one the one
hand good for global climate, and on the other hand for the local one. My room can get pretty hot
during the summer, burning a lot of energy with old monitors did definitely not help that.

I already love my new toys. :-)