All ideas on x-less solution are welcome. As Thiago points out the solution to 
be targetted is wayland managing the Egl surfaces and then a product specific 
window manager. Input drivers need consideration too.

Mikk0 Terh0

On Dec 27, 2010, at 4:14 PM, "ext Thiago Macieira" <[email protected]> wrote:

> On Monday, 27 de December de 2010 15:01:55 john pratss wrote:
>> Hi all,
>> why is qt embedded not being used as part of UI development framework and
>> why is qt X11 is being used instead???
> 
> For two main reasons:
> 
> 1) inside Qt: Qt for Embedded Linux is an older codebase, with a lot of 
> hacks, 
> created for a class of embedded devices with very, very limited capabilities. 
> This class of devices is disappearing and MeeGo is definitely not targetting 
> them: MeeGo targets the high-end, where memory and graphics capabilities 
> aren't that constraining. 
> 
> Qt for Embedded Linux requires writing a screen driver, a mouse driver, a 
> keyboard driver, etc. using API that is not guaranteed to stay binary 
> compatible. Also, its architecture was designed around frame buffers, and the 
> code assumes in many places to have access to the pixels themselves. This 
> architecture is not the best one for OpenGL ES-capable hardware acceleration.
> 
> What's more, Qt for Embedded Linux is being replaced by the Lighthouse 
> Project 
> with Qt Platform Abstraction, which is more suitable for hardware 
> acceleration. When we switch to Wayland, we'll switch to QPA too (and 
> probably 
> require a MeeGo 2.0 version).
> 
> 2) outside Qt: the ecosystem. We want to run many non-Qt applications and the 
> tecnology that exists from the ecosystem and community. Those currently use 
> X11 because there's nothing better. Using QWS is not an option. Only when 
> Wayland is mature will there be an alternative, so we can ask the community 
> to 
> use Wayland.
> 
>> At-least for the handset and IVI based devices where there are memory and
>> processing power constraints qt embedded is a better alternative than qt
>> X11.
> 
> Handset is not so much an issue. X11 runs fine on 256 MB of memory, as 
> evidenced by Maemo 5 and MeeGo on the N900. Those devices have 600 MHz to 1 
> GHz of CPU today and are now coming to dual-cores (ARMs, MIPSes, since Atoms 
> are there already).
> 
> IVIs have a different market outlook, but they are also looking at high-end. 
> Remember that IVIs have a lifespan of 5 to 7 years, whereas handsets get 
> replaced within 2 to 4. Anyone using ARM11 for IVI today is shooting 
> him/herself in both feet, in my opinion.
> 
> So I don't buy your argument. But even if your argument were true, it doesn't 
> mean MeeGo must address those segments. Like I said before, MeeGo is 
> addressing the high-end. And, moreover, I also don't think QWS is the best 
> architecture or is abetter alternative than X11, like you siad. 
> 
> QPA / Lighthouse, yes, that is a better alternative. But we need a windowing 
> server first and Wayland is not ready.
> 
> -- 
> Thiago Macieira - thiago (AT) macieira.info - thiago (AT) kde.org
>  Senior Product Manager - Nokia, Qt Development Frameworks
>      PGP/GPG: 0x6EF45358; fingerprint:
>      E067 918B B660 DBD1 105C  966C 33F5 F005 6EF4 5358
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