Blurring is the act of altering images so they appear out of focus. My Maestro[2] and other illustriuos people already talked extensively about this topic here on planet KDE. However you don’t improve the world until a technology becomes available to everybody, right?

Then some days ago I read on notmart‘s blog that plasma and kwin supported blurring the background on windows.. so I rebuilt KDE4 svn, restarted it, and… boy.. does it make a difference! Look at Marco’s blog or at this picture I stole from him! All the popups become instantly more readable, even krunner does, and you immediately get the feeling that the plasma panel and all the systray applets really are above your desktop and they look as they were made of some glass/plastic material.

So: why limiting this just to some plasma applets? Well, I think that the usage of this effect must be wise, however I wanted that for my app too…

…’cause I like eye-candy!

After a quick tour through the beautiful KDE svn I grabbed all the needed source code and loaded Fotowall in creator. Since I already had the structure for the blur-behind on windows in place, adding the KDE4 effect was really easy. Here are some samples of what you can get:

To activate the back blur you need:

• obviously an application with a transparent background. Qt easily allows to work with transparency on top-level windows.
• you have to enable the “blur” effect in kwin’s “desktop effects” configuration.
• a couple of lines of code to ask kwin to activate blurring to your window.

Here is the code that does the magic:

#if defined(Q_WS_X11)
/**
  Blur behind windows (on KDE4.5+)
  Uses a feature done for Plasma 4.5+ for hinting the window manager to draw
  blur behind the window.
*/
#include <X11/Xlib.h>
#include <X11/Xatom.h>
#include <QX11Info>
static bool kde4EnableBlurBehindWindow(WId window, bool enable, const QRegion &region = QRegion())
{
    Display *dpy = QX11Info::display();
    Atom atom = XInternAtom(dpy, "_KDE_NET_WM_BLUR_BEHIND_REGION", False);

    if (enable) {
        QVector<QRect> rects = region.rects();
        QVector<quint32> data;
        for (int i = 0; i < rects.count(); i++) {
            const QRect r = rects[i];
            data << r.x() << r.y() << r.width() << r.height();
        }

        XChangeProperty(dpy, window, atom, XA_CARDINAL, 32, PropModeReplace,
                        reinterpret_cast<const unsigned char *>(data.constData()), data.size());
    } else {
        XDeleteProperty(dpy, window, atom);
    }
}
#endif

And then you can activate the blur on the caller widget with:

    kde4EnableBlurBehindWindow(winId(), true);

You could add the back blur to your application too, however I advise you that the interface is not standardized, so don’t blame either me or the kwin authors if something changes. Here is another picture, because everybody loves them

And now, as a side note, a picture from my new work place: the beautiful city of San Diego, blessed by the sun and by a ton of great programmers that by some chance happen to be co-workers of me With all the blue sky and long days, I can’t imagine a more inspiring place for making new blog posts and code experiments!

Notes:
[1] obviously the name is completely made up
[2] Italian word meaning “teacher” as in school or life teacher

KDM Ideas

1. QML in KDM
   This is all about animations, user interaction and eye candy. See this for example.
2. Plasma in KDM
   This is about consistence and configurability.
3. Webcam Login (face recognition) in KDM
   Show your face (or Mona Lisa‘s one) and you’re in! No password typing needed. Integrating with the pam-face-authentication may be the smart way to go.
4. Fingerprint Login in KDM
   This is KDE’s most requested feature… you can’t be wrong implementing it

KDE Ideas

1. Unified webcam library
   Webcam’s are being utilized a lot lately: they’re cheap, widespread, and they’re working good under Linux. Projects come out with webcam support, like Fotowall, Kamoso, Kopete and there are efforts to get it working in Phonon.
   Note that a camera is a source of video, images but also can be used for authentication and may even be used for user input – can you imagine manipulating stuff with your fingers? Note that webcams must usually be read in single instance, so the approach here might be 1 Qt-Only userspace daemon supporting multiple connections.
2. Unified Theme Manager
   One theme manager to rule them all: styles, colors, plasma theme, windeco & all. Of course the themes must be packed and shared in a binary-compatible manner with any other KDE system (yes, the challenges are there..
3. Unified Configuration Panel
   Making systemsettings really the one and only configuration tool and provide backends to the distributions for adding/changing modules so KDE systems will have the same feeling for configuring the system. Some modules like ‘partition disk’, ‘edit boot menu’ and ‘manage startup programs’ (daemons) should be added and left to the distribution for implementation – I think they will. Note that current systemsettings lets you configure the joystick even if you don’t have one (!).
4. KWIN: draggable windows
   And for windows I mean (actually J. Janz means) the whole non-interactive panel. Blank space as well as inactive labels should be draggable. From the user POV there is no window-deco + window contents. It’s a panel, let’s use it, move it, resize it, context-menu-it as a whole.
5. Raytraced UI
   I’ll blog more about this, but this is a little thing I’d really like to do but I don’t know if I will find time to do that. Do you think that iPhone gui is cool? Raytrace the .ui high-level gui definition format and you’ll get something better. Glassy too. Mail me if you want to know more about this

Conclusion

I’m sorry I missed some interesting suggestions but I don’t have space here to detail them; just look to my previous blog entry’s comments to find more about BasKet note pads integration into Plasma, file browsing enhancements (context dependent actions, menus, warnings and kparts) qt4 gui for vi, etc.

As someone pointed out there is quite a bit of overlap and dispersion between the ways to collect ideas. I can count:

• KDE Bugzilla’s wishlist
• KDE Forum’s brainstorm
• distribution specific bug trackers
• blog posts (ehm….:-)
• GSOC ideas
• kde-look’s brainstorm
• developers mailing lists
• other bugtrackers
• techbase or userbase
• direct mails and irc chats

Directing users to provide their feedback in a low-dispersive, constructive, modern, layered (from generic directions to specific actions) and focused way is probably one of the challenges that should be added to Aaron’s list for 2010.

Collecting Ideas

I want to blog about some cool things to do for the KDE project on week-1 2010. I’ve got just a couple of good ideas, so I’m asking you to add your ideas so we can make a good collection of nice things to do. You can either reply to this post (don’t be shy, just post it!) or send it to me at <enrico.ros@gmail.com>.

Sharing your idea with the community raises the chance of seeing it implemented!

The KDE login Manager

The login manager is the “insert password” dialog that gets in the way when you want to use your computer. Of course you may not be the only user of the machine, so it’s somewhat needed when you share the seat. Some facts:

Kdm Top to Bottom

Qml to the rescue!

What if we throw away (or keep for “retro-compatibility”) the classic and themer frontends and just add a frontend using QML? This is the name of the language of the Qt Declarative module, that has just seen the light and will be merged into Qt for the 4.7 release.

Imagine this:

• theme creators will have 100X or more expressive power: make snow! login via a tetris puzzle! bounce my webcam picture!
• there will be animated themes (for login, user change, logout, etc..) or simple ones for more ‘classic’ kind of people
• kdm only needs to add a couple of bindings to the qml runtime, like functions for logging in and shutting down / suspend the system
• there is no need for compiled binaries, packages will be interpreted by the qml runtime – finally a painless get-hot-new-stuff (compared to plasma widgets, at least).

Conclusion

For those who don’t know me, I’m a long time KDE user (since 2.2), I worked on several KDE projects like okular, kdm, amarok, konqueror, as well as releasing other software like Fotowall and other stuff on various repositories.

This planet is the collector of many of my favorite blogs and it’s an honor for me to be here.

See you soon (with some developer tool hacks…stay tuned) !

Lista dei miei sorvegliati speciali 2009

• nepomuk “Improving Search and Virtual Folders”
  creazione di un widget standard per la ricerca con Nepomuk da integrare in Dolphin, nel File Dialog, etc.. e miglioramento del backend ‘nepomuksearch:’ + virtual folder (es. Immagini = tutte le immagini presenti nel pc)

• phonon “Visualizations”
  estrae statistiche (spettro, metriche varie) dal flusso audio di Phonon per fornire i dati a visualizzatori. Utile per tutto kdemultimedia oltre ai vu-meter fai da te!

• kdevelop “C++ refactoring support”
  datecelo e svilupperemo al triplo della velocita’ dateci anche “static code visualization” e ci regalate un altro emisfero cerebrale. (il motore C++ di kdevelop spaccadibbrutto, la gui/workflow e’ 10 volte meno usabile di QtCreator)

• plasma “New Widget Explorer”
  l’attuale ‘just sucks’.. c’e’ bisogno di disabilitare i plasmoidi non validi, di raggrupparli per tipologia, di avere un dialog che presenti piu’ contenuto in molto meno spazio (e speriamo che tolgano l’odiosa stellina mangia spazio )

• plasma “PlasMate Editor”
  puo’ aiutare la diffusione dei plasmoidi, ma solo *se fatto a regola d’arte*, altrimenti brucia la bonta’ di plasma.

• plasma “Media Center Components”
  componenti Multimediali per Plasma. Alessandro puo’ fare un bel lavoro qui. Optimization is needed btw

Ce ne sono ovviamente molti altri di interessanti (tra i 38 assegnati a KDE), e non parliamo dei progetti di Gnome, LLVM, GCC, Gentoo, e degli altri 900

Da oggi, 11 gennaio, KDE 4.0.0 è una realtà che possiamo usare sui nostri desktop, un tassello importante che porta nuove tecnologie alla porta di tutti, senza distinzioni. Multipiattaforma, integrato, curato nell’aspetto, nei suoni, nell’interazione con l’utente, e fonte di ispirazione per me e, mi auguro, per i miei compagni di ventura in M31.

Voltiamo pagina nei nostri desktop. Il nuovo inchiostro lo metteremo noi.

- Be Free.