annoying bug with alt-tab switching on a workspace with at least one fullscreen window

[oh]

Binary package hint: compiz

on workspaces with one fullscreen window and several regular windows (possibly hidden behind the fullscreen window), pressing alt-tab to switch windows will show a black screen when the fullscreen window is in focus in the switcher.

This is gutsy, updated/upgraded via apt-get yesterday, running on a lenovo thinkpad x60 w/intel 945 graphics. OpenGL programs work nicely on this machine, with compiz they are somewhat slower. I run the normal X server, not Xgl, since when I enable Xgl everything except panning between workspaces gets very slow (wobbling, for instance).

I have enabled "extra" desktop effects - wobbling, panning workspace switching (not the cube). I run many workspaces and switch between them with ctrl-f1, ctrl-f2 etc.

I usually dedicate some workspaces to running applications in full-screen (not maximized, but full-screen) mode - an xterm for irc on one workspace, a fullscreen firefox on another, etc. Normally I have a desktop shortcut (shift-ctrl-enter) to toggle fullscreen, so i use it a lot.

[Peter Makowski (petermakowski)]

I can confirm the bug.

I have the ATI radeon 9250 card (aiglx)

[Peter Makowski (petermakowski)]

I observed also that the full-screen wine applications becomes black and hangs when they're focused in the switcher.

[Npl (npl)]

I can confirm this.
Ubuntu 7.10 (AMD64) + Nvidia GF 8600 GT (nvidia-glx-new driver)

Further, this problem goes away if you install compizconfig-settings-manager and untick "Unredirected Fullscreen windows" in the general options. The downside is that this comes with a performance-penalty especially in OpenGL Games (as that feature would allow Fullscreenapps drawing directly to the screen). Not sure if its a bug that can be fixed, its prolly that you have to choose between slower fullscreen-performance or rendering bugs.

[Chris Halse Rogers (raof)]

Please don't assign people to bugs unless you're sure they want to be assigned.

As for the actual bug - I can't reproduce it here. Alt-tab with a couple of fullscreen gnome-terminals, a fullscreen totem, and some nautilus windows behaves just fine. It doesn't seem to be an inherent problem with unredirect-fullscreen-windows.

@Piotr: For your specific wine example, I'd blame that on the open-source drivers not having the infrastructure yet to do OpenGL direct rendering + Composite nicely. Once redirected-direct-rendering is supported, I'd guess your particular example (fullscreen OpenGL window in the switcher) would work.

[Kai Schroeder (kai-schroeder)]

i can confirm this problem in hardy using nvidia-glx driver

[Alissa Harrison (alissa-m-harrison)]

I can confirm this as well with only one screen opened full-screen (Firefox). When I press Alt-tab to switch applications, the screenshot of Firefox is black and the screen around the switcher is black. I am running Ubuntu Gusty with Nvidia Quadro NVS 280 SD (nvidia-glx drivers 1.0.9639+2.6.22.4-14.10).

[Peter Makowski (petermakowski)]

Please change the importance to medium... Developers don't seem to even notice this bug.

[Travis Watkins (amaranth)]

The issue that you reported is one that should be reproducible with the live environment of the Desktop CD of the development release - Hardy Heron. It would help us greatly if you could test with it so we can work on getting it fixed in the actively developed release. You can find out more about the development release at [WWW] http://www.ubuntu.com/testing/

[Kiwinote (kiwinote)]

Still confirmed with compiz 1:0.7.0-0ubuntu3 in hardy using nvidia-glx-new 169.09.

>Hold alt down
>press tab until selected window is a full screen one
==>fullscreen window (terminal and firefox tested) flickers (black and white)
>release alt
==>window acts normally

[Travis Watkins (amaranth)]

Same version of compiz, same driver, I cannot reproduce with terminal, firefox, totem, or a game running through wine.

Is there anything else I have to do to reproduce this?

[Kiwinote (kiwinote)]

The procedure I followed was:
>close all windows (shouldn' t make a difference, but just to be sure)
>launch firefox or totem
>switch into fullscreen mode (F11)
>hold alt down
>press tab once
=>window is black and flickers roughly once a second with parts of what the
window should look like.
>release alt

I'm running compiz in default configuration with "extra" visual effects.

If there is anything else that may influence it, please let me know.

On Thu, Feb 21, 2008 at 7:43 PM, Travis Watkins <email address hidden> wrote:

> Same version of compiz, same driver, I cannot reproduce with terminal,
> firefox, totem, or a game running through wine.
>
> Is there anything else I have to do to reproduce this?
>
> --
> annoying bug with alt-tab switching on a workspace with at least one
> fullscreen window
> https://bugs.launchpad.net/bugs/153205
> You received this bug notification because you are a direct subscriber
> of the bug.
>

[Alissa Harrison (alissa-m-harrison)]

I can confirm this bug on another machine: Toshiba Tecra M2 laptop with Nvidia Geforce Go5200 card. Using internal laptop display and external VGA monitor.

The normal desktop effects are enabled under System -> Preferences -> Apperance. When I open Firefox, press F11, and press Alt-tab to switch windows there is severe black flickering.

I am including my xsession-error, xorg.0.log, and output from lspci -vvnn.

[Alissa Harrison (alissa-m-harrison)]

Confirmed by several users, have exact steps for reproducing, and log files for reference.

[Travis Watkins (amaranth)]

Following all of these different ways to reproduce I _still_ cannot reproduce this on hardy with a Geforce Go 7400 and the nvidia-glx-new driver.

[Alissa Harrison (alissa-m-harrison)]

Travis,

Reading your message, I was going to say that maybe it's specific to the drivers, but the Tecra M2 that I confirmed the bug on is also using the nvidia-glx-new driver.

Nevertheless, I'm running a Go 5200 which is considerable less powerful than the Go 7400. I'm guessing (though it's a bit of a stab in the dark), this bug is either due to lack of sufficient video memory or poor handling of video memory. It's possible that you can't confirm the bug because your video card has plenty of memory to burn.

Regardless, we should have enough data for the developers to look into this problem and figure out whether this is a hardware or software limitation, right?

[Travis Watkins (amaranth)]

No, we really don't have enough information because there could be several things at fault here and without being able to see the problem I cannot even begin to figure out what is going on.

[Alissa Harrison (alissa-m-harrison)]

Ok, since I can reproduce this problem on two different machines, then what information can I provide that will be more useful? I didn't see any errors at the time I confirm the error in my .xsession-errors file, so I am assuming that you will need more than this. Is there a way I can run compiz with more debug info?

[Michael Rooney (mrooney)]

Hi Travis, I can confirm this on Hardy. Two interesting things to note, that may help:

 - Only the default alt+tab switcher exhibits this problem. The scale plugin and shift switcher show the preview just fine.
 - The preview is initially shown fine if it is unselected. IE if the fullscreen window is currently focused and alt+tab is pressed, the next window will be selected and a preview of the fullscreen window shows fine next to it. Only when you tab TO the fullscreen window does it turn black; it shows up fine until then.

I hope this helps.

[Jonathan Jogenfors (etnoy)]

I can also confirm this bug, on a Thinkpad T30 with the standard r100 Radeon card. Unless I untick "Undirect fullscreen windows" in the compiz settings, when changing workspaces with the "desktop wall" plugin from a max:ed firefox on one workspace, to a xterm on another one, xterm most of the time loses doesn't respond to keyboard inputs. The window appears focused, and it doesn't help to click either the title bar or the window with the mouse. I need to alt-tab to another window and back for xterm to respond again.
I use workspaces a lot, and this happens 70-80% of the time when switching to xterm, so it really slows my work down.
Please ask for more information and I will happily provide it.

Jonathan

[Taru (aa55cc)]

I can confirm this on a -8.04 (hardy) -Pentium 4 -Nvidia Radion 7600gt -Desktop effects (normal/moderate)

Really annoying since I use the epiphany web browser F11 a lot. Everytime I update, I check and see if this is fixed yet, it's that important to me.

Andy

[Travis Watkins (amaranth)]

I can see this now on a Sony Vaio with a Go 6200. I guess it only affects older cards.

[safinace (safinace)]

To everyone who is experiencing this bug, try this:

a. type [ccsm] to open up [advanced desktop effects settings]
b. goto [general options]
c. uncheck [unredirect fullscreen windows]

I have a [GeForce 6200] and that solved my problem.

[Սահակ (petrosyan)]

I am seeing this bug with Dell Precision 380 workstation.
ATI Radeon X1800 video card.
fglrx proprietary drivers.

[dfalk (dfalk)]

Extra confirmation here. Please let me know what I can do to give more information. Unchecking "unredirect fullscreen windows" does work, but do I want this? I play games on this computer...

Vid card is nvidia go 8400gs, using the nvidia drivers

[Stephen_A (sra97)]

Had this problem with a Dell 1150 running 8.04. Saniface's instructions above worked perfectly to fix it.

[Jonathan Jogenfors (etnoy)]

My previous comment was incorrect, the above fix does NOT solve the problem for me. Notable also is that the problem isn't limited to alt-tab:ing, but also occurs when switching workspaces.
Thinkpad T30.

[Caldur (icthusfish)]

I can confirm this as well, and the above fix did not work for me. As long as I don't have a full-screen window, my alt-tabs are quite zippy. I can even leave a full-screen window open on one workspace, and switch to another, and on that second workspace my alt-tabs are perfectly normal. But if I try to alt-tab on a workspace that has a full-screen window on it, it takes a good 2-3 seconds. It's really, really bad.

Any ideas for a work around?

[Jonathan Jogenfors (etnoy)]

Please ignore all my input on this bug, I have a different issue than the original poster. I apologize for the confusion :)

[Gigi (gigi33)]

Still confirmed with compiz 0.7.8 in intrepid using nvidia-glx-180

Kiwinote wrote on 2008-02-21:
> Hold alt down
> press tab until selected window is a full screen one
> ==>fullscreen window (terminal and firefox tested) flickers (black and white)
> release alt
> ==>window acts normally

[Սահակ (petrosyan)]

this bug seems to have been fixed in Ubuntu 9.04
compiz-0.7.9+git20090211-0ubuntu4

[Kiwinote (kiwinote)]

Also confirming that this seems fixed in jaunty. Feel free to re-open the bug if you still have this issue in jaunty.