kde 4 (kwin) special effects not working

[kost BebiX]

When you try to enable special effects in you guest kde4 machine it says that it can't. Someone already wrote about this bug some time ago, but it's not in bug tracker, so I'm posting it :-)

here's an old forum thread ​http://forums.virtualbox.org/viewtopic.php?f=3&t=16244

Thank you.

[Technologov]

This is still true for v3.1.2.

Host: Windows XP + Intel GPU + Intel Core 2 CPU + VBox 3.1.2

Guest: Mandriva Linux 2010, 32bit

-Technologov

[Technologov]

Mandriva Linux 2010 - VBox Log (by Technologov)

[Technologov]

OpenGL_cannot_be_enabled.PNG screenshot (by Technologov)

[Diddi]

The ticket is now over 1 year old. When is there finally a solution for this? The driver VBOXVIDEO missing actually just some OpenGL extensions. That should add it easily.

[Frank Mehnert]

So where is your patch? Regarding your discovery that this ticket is more than one year old: You are not aware that there are a couple of other tickets open as well, are you?

[Michael Thayer]

diddi04: as you might suspect, there is a bit more involved here than adding support for a couple of OpenGL extensions. To cut a long story somewhat short (I am not the person implementing this, so some details may not be quite right), our DRI driver is not a real DRI driver, but rather a stub that loads our OpenGL replacement library into a running process so that it is used instead of Mesa. We did this so that we only had to implement one OpenGL library for all supported guests (the library mainly proxies OpenGL requests from the guest to the host, so it doesn't need to be very different on different guests). However compositing places additional demands on the library due to the extra co-operation needed between the X server and the clients, and at least for KWin we don't handle the server side correctly.

We understand that this is annoying for you, but unfortunately due to lack of resources, and because we have other priorities we do not plan to fix this in the immediate future (I am sure that you will understand that we wish to set our development priorities ourselves). As Frank pointed out, we make all source code available so that people who want features that we don't currently have time for are not forced to depend on us, but can equally go to anyone else capable of implementing them (or even contribute the features themselves). We generally don't make a fuss about accepting code contributions as long as we are satisfied that they won't cause problems for other users.

[Greg Davis]

For some reason, Kwin in KDE4 in most cases loads and falls back to Xrender or software rendering because of the lack for compositing, essentially that is the missing feature in VBox. My recent update to KDE 4.5.4 from 4.5.1 actually broke the window manager because of this. Kwin seemed to freeze on login because it no longer was happy with the missing extension. Better it did that because it forced me to look into this and discovered a workaround.

Workaround: install the compiz window manager, install the emerald window-decorator, install the "compiz-fusion-icon", from the default applications Kconfig menu set the window-mananger from Kwin to compiz, use the compiz-fusion-icon to start the settings tray-icon, and use the settings tray-icon to configure compiz and emerald.

Hopefully that will point people who stumble upon this bug report in the right direction until VBox supports DRI/OpenGL in a manner that makes Kwin happy. After some tinkering with this, my KDE4 guest VM runs like stink in VBox.

[kost BebiX]

Well, I've just tried to turn special effects in guest fedora 15 machine with latest kde 4.6 and it... failed, but then it succeded!) I mean, you just have to disable "compatibility checking" when enabling special effects and some other option which I don't remember. So... should we close this bug or what? Thank you.

[Technologov]

Excuse me, but how-to disable "compatibility checking" ?

I really would like to have KDE4 (kwin) special effect in my Linux guests.

-Technologov

[kost BebiX]

​http://dl.dropbox.com/u/865508/rawhide%20%5B%D0%A0%D0%B0%D0%B1%D0%BE%D1%82%D0%B0%D0%B5%D1%82%5D%20-%20Oracle%20VM%20VirtualBox_069.png here are settings that work.

[Technologov]

update: Yahoooooooooo !

I was able to make it !

Host: Kubuntu 10.04 LTS 64-bit, Core 2 Q6600, ATI Radeon HD 3850 (+proprietary drivers) + VBox 4.0.4

Guest: Kubuntu 10.04 LTS 64-bit

Kubuntu 10.04 has KDE 4.4, and to make it work, I changed "OpenGL mode" to "Fallback", and removed "Enable Direct Rendering" checkbox.

Now both flipping windows (Vista-like) and Desktop cube (Compiz-like) render fine using kwin ! (But very slow)

Thank you for advice !

-Technologov

[Technologov]

update: it turns out the same works without OpenGL acceleration at all. (i.e. if I disable 3D acceleration completely in VirtualBox), which means KDE 4.4 basically fallbacks to OpenGL software rendering.

It renders, yes, but I cannot work at speeds below 1 fps.

So this bug should not be closed for now.

-Technologov

[Greg Davis]

There is at least one GL extension that the VBox renderer doesn't support that KWin requires, and it is for compositing. I don't know if Vbox code needs to be changed, or if Vbox simply relies on a library to provide rendering, and that library does not support compositing. Chromium sticks out in my mind.

[Technologov]

soo...

After speaking with KDE people on this issue, they say that "texture from pixmap" in "direct rendering mode" is clearly failing.

If improving VBox drivers is too difficult, maybe we can ask KDE team to port Kwin to VirtualBox drivers.

See here: ​https://bugs.kde.org/show_bug.cgi?id=269594

-Technologov

[kost BebiX]

Ok, gave my +20 vote there. You can do the same)

[Mauro Molinari]

I'm also interested in this bug to get fixed. Thank you.

[dterrahe]

Using Virtualbox 4.2.12 on windows 8 host and debian amd64 unstable, xserver 1.12.4 and kde 4.10.2 on guest, this now works for me by creating a file ~/.kde/env (for the user, not root) containing:

export KWIN_DIRECT_GL=1
export KWIN_COMPOSE=O2

That is Oh Two, not zero two, zero or just Oh.

This sometimes causes problems with the host key not responding or the Mini Toolbar not showing. This can lead kwin to disable compositing by setting a flag in its config file. So if it stops working after a while, check ~/.kde4/share/config/kwinrc and if there is an entry OpenGLIsUnsafe=true reset it to false.

Translucency, wobbly windows, coverflow all working.

[aeichner]

Please reopen if still relevant with a recent VirtualBox release.