Qt 4.6

[dridk]

does somebody try to use Qt4.6 ?
I want to buy many Touch book for my hospital, but I need to be sure that's working well.

[dridk]

Arg... Please change my subject ! It's Qt4.6 .

[matthias]

I tried both Qt/X11 and Qt/Embedded on a Gentoo image and it works well.
I also developped a handwriting recognition Qt Input Method (similar to cellwriter for GTK).

[alexandre]

matthias: sounds interesting. Which gentoo image did you eventually use, and how did you get Qt4.6 to work by compiling it directly on the device?

Alexandre

[matthias]

Hi,
I used an official arm stage3 and crosscompiled from there.
I've found Gentoo crosscompilation architecture much better than OpenEmbedded.
OE eats all my ressources (CPU,RAM and disk space) without results.

Using Gentoo, crosscompiling is not different from a native compile (except for unsupported ebuilds which need patches to get their build system to work).
Also you benefits from more than uptodate packages since crosscompiling is supported in the same ebuilds as used by all straight gentoo systems.

For example. OE is (was?) using an outdated GCC because there isn't enough maintenance work power to bump the package still requiring an old GCC.
This forces me to downgrade my crosscompiler to run gentoo packages on AIOS

I'm publishing my Gentoo overlay on gitorious:
http://gitorious.org/gentoo-kde-cross-overlay

Compiling a base system with Qt/Embedded (QWS) or X11 + Qt/X11 is supported.
I also managed to run a semi-usable KDE on the touchbook.
While I could have worked on getting the complete KDE experience, I think KDE has shortcomings which makes it inefficient on embedded hardware.
I identified three major memory consumer in KDE:
- plasma use SVG themes which needs to be cached for acceptable performance.
- the KIO network abstraction system forks a new process for each transaction (probably to avoid crashes in applications)
- KWin compositing which keeps a backing store of all windows (thankfully an optional feature)

Also KDE would require a fundamental UI rework to be usable on a small touchscreen display (being done as part of the KDE Mobile project using QML)

That's why I'm currently trying to develop my own environment based on Qt.
I'm reinventing a wheel that would be efficient, easy to modify (at least for me) and designed with touchscreen and small display in mind.
But first, I have to develop a required dependency to any lightweight graphical environment : a lightweight display server.
neither X11 nor QWS are up for this task, but I'm quite fond of Wayland's design (though I'm not sure if WSEGL would allow shared egl surfaces)

I'll resume my crosscompiling work as soon as I receive a smartbook.
Don't hesitate to IM me if you need anything.

PS: sorry for the long unrelated answer but I like to write about my projects