| Summary: | Upgrade to Qt 4.6 breaks Kephal multi-head support | ||
|---|---|---|---|
| Product: | [Unmaintained] kephal | Reporter: | Marcel Hasler <mahasler> |
| Component: | General | Assignee: | Aike J Sommer <dev> |
| Status: | RESOLVED UNMAINTAINED | ||
| Severity: | normal | CC: | cfeck, mahasler |
| Priority: | NOR | ||
| Version: | unspecified | ||
| Target Milestone: | --- | ||
| Platform: | Gentoo Packages | ||
| OS: | Linux | ||
| Latest Commit: | Version Fixed In: | ||
| Sentry Crash Report: | |||
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Description
Marcel Hasler
2009-12-11 20:52:31 UTC
I found this thread http://markmail.org/message/huibm7di5wighhkb which mentions a NoXRandR option for Kephal which is supposed to work around such problems. Unfortunately that option has no effect for me. However, the other workaround mentioned, disabling Kephal completely, works for me. I've renamed the kephal.desktop file to make sure kded doesn't find it. Now everything works the way it should. This is really weird... I hav no idea, why an upgrade of Qt would lead to this behavior! Just to have a little more hints of where to look: - Is your setup xrandr 1.2? - Can you post the output of `xrandr` before and after disconnecting the monitor? I have RandR 1.3 on my system. However, I'm using the Nvidia drivers which to my knowledge still only support RandR 1.1. The output of xrandr before disconnecting: Screen 0: minimum 320 x 175, current 2464 x 900, maximum 2464 x 900 default connected 2464x900+0+0 0mm x 0mm 1440x900 50.0 55.0 51.0 1024x768 51.0 56.0 52.0 832x624 52.0 65.0 53.0 800x600 53.0 66.0 54.0 720x400 54.0 68.0 55.0 700x525 57.0 71.0 640x512 58.0 73.0 640x480 59.0 74.0 640x400 60.0 75.0 640x350 61.0 76.0 576x432 62.0 77.0 512x384 63.0 78.0 416x312 64.0 79.0 400x300 67.0 80.0 360x200 69.0 81.0 320x240 70.0 82.0 320x200 72.0 83.0 320x175 73.0 84.0 2464x900 55.0 51.0* And after disconnecting: Screen 0: minimum 320 x 175, current 1440 x 900, maximum 2464 x 900 default connected 1440x900+0+0 0mm x 0mm 1440x900 50.0* 55.0 51.0 1024x768 51.0 56.0 52.0 832x624 52.0 65.0 53.0 800x600 53.0 66.0 54.0 720x400 54.0 68.0 55.0 700x525 57.0 71.0 640x512 58.0 73.0 640x480 59.0 74.0 640x400 60.0 75.0 640x350 61.0 76.0 576x432 62.0 77.0 512x384 63.0 78.0 416x312 64.0 79.0 400x300 67.0 80.0 360x200 69.0 81.0 320x240 70.0 82.0 320x200 72.0 83.0 320x175 73.0 84.0 2464x900 55.0 51.0 Looking at the output I'm wondering how Kephal managed to detect the correct layout in the first place. Obviously Nvidia's RandR implementation can't really be trusted. Since QDesktopWidget reports the correct values but Kephal doesn't (even when using QDesktopWidget itself), I would assume the problem to be either Dbus-related or somewhere in Qt's container classes. I'll try to add a few debugging statements to Kephal's code in order to find out if and where it has correct values and where the values start going wrong. Maybe that can help to pin down the actual problem. Could you kill kded4 and start it from a terminal? That should give you a few lines of debugging output from kephal... Those might also help to clarify... Interestingly, Kephal doesn't seem to detect the screen change at all. Here's all I get (with NoXRandR enabled): kephald starting up adding an output 0 with geom: QRect(0,0 1440x900) output: "SCREEN-0" QRect(0,0 1440x900) 2097261 true false load xml connected: 1 looking for current "SCREEN-0" known "*" has score: 0.125 screen: 0 QRect(0,0 1440x900) looking for a matching configuration... connected: 1 looking for current "SCREEN-0" known "*" has score: 0.125 found outputs, known: false activate external configuration!! registered the service: true screens registered on the bus: true outputs registered on the bus: true configurations registered on the bus: true That's all printed when Kephal starts up. Changing the screen layout after that doesn't produce any output at all. Here's the same without NoXRandR: kephald starting up XRANDR error base: 173 RRInput mask is set!! RandRScreen::loadSettings - adding mode: 346 1440 x 900 RandRScreen::loadSettings - adding mode: 347 1024 x 768 RandRScreen::loadSettings - adding mode: 348 832 x 624 RandRScreen::loadSettings - adding mode: 349 800 x 600 RandRScreen::loadSettings - adding mode: 350 720 x 400 RandRScreen::loadSettings - adding mode: 351 700 x 525 RandRScreen::loadSettings - adding mode: 352 640 x 512 RandRScreen::loadSettings - adding mode: 353 640 x 480 RandRScreen::loadSettings - adding mode: 354 640 x 400 RandRScreen::loadSettings - adding mode: 355 640 x 350 RandRScreen::loadSettings - adding mode: 356 576 x 432 RandRScreen::loadSettings - adding mode: 357 512 x 384 RandRScreen::loadSettings - adding mode: 358 416 x 312 RandRScreen::loadSettings - adding mode: 359 400 x 300 RandRScreen::loadSettings - adding mode: 360 360 x 200 RandRScreen::loadSettings - adding mode: 361 320 x 240 RandRScreen::loadSettings - adding mode: 362 320 x 200 RandRScreen::loadSettings - adding mode: 363 320 x 175 RandRScreen::loadSettings - adding mode: 372 2464 x 900 RandRScreen::loadSettings - adding mode: 373 1440 x 900 RandRScreen::loadSettings - adding mode: 451 1024 x 768 RandRScreen::loadSettings - adding mode: 452 832 x 624 RandRScreen::loadSettings - adding mode: 453 800 x 600 RandRScreen::loadSettings - adding mode: 454 720 x 400 RandRScreen::loadSettings - adding mode: 455 700 x 525 RandRScreen::loadSettings - adding mode: 456 640 x 512 RandRScreen::loadSettings - adding mode: 457 640 x 480 RandRScreen::loadSettings - adding mode: 458 640 x 400 RandRScreen::loadSettings - adding mode: 459 640 x 350 RandRScreen::loadSettings - adding mode: 460 576 x 432 RandRScreen::loadSettings - adding mode: 461 512 x 384 RandRScreen::loadSettings - adding mode: 462 416 x 312 RandRScreen::loadSettings - adding mode: 463 400 x 300 RandRScreen::loadSettings - adding mode: 464 360 x 200 RandRScreen::loadSettings - adding mode: 465 320 x 240 RandRScreen::loadSettings - adding mode: 466 320 x 200 RandRScreen::loadSettings - adding mode: 467 320 x 175 RandRScreen::loadSettings - adding mode: 486 2464 x 900 RandRScreen::loadSettings - adding mode: 487 1440 x 900 RandRScreen::loadSettings - adding mode: 488 1024 x 768 RandRScreen::loadSettings - adding mode: 489 832 x 624 RandRScreen::loadSettings - adding mode: 490 800 x 600 RandRScreen::loadSettings - adding mode: 491 720 x 400 RandRScreen::loadSettings - adding crtc: 344 RandRScreen::loadSettings - adding output: 345 Setting CRTC 344 on output "default" (previous 0 ) CRTC outputs: (345) Output name: "default" Output refresh rate: 50 Output rect: QRect(0,0 1440x900) Output rotation: 1 XRandROutputs::init added output 345 adding an output 0 with geom: QRect(0,0 1440x900) output: "SCREEN-0" QRect(0,0 1440x900) 3801197 true false load xml connected: 1 looking for current "SCREEN-0" known "*" has score: 0.125 screen: 0 QRect(0,0 1440x900) looking for a matching configuration... connected: 1 looking for current "SCREEN-0" known "*" has score: 0.125 found outputs, known: false activate external configuration!! registered the service: true screens registered on the bus: true outputs registered on the bus: true configurations registered on the bus: true Again, changing the screen layout isn't detected. What is printed when you start with both screens connected? Ok, that way Kephal detects the screens correctly. Here's the output: kephald starting up XRANDR error base: 173 RRInput mask is set!! RandRScreen::loadSettings - adding mode: 346 1440 x 900 RandRScreen::loadSettings - adding mode: 354 2464 x 900 RandRScreen::loadSettings - adding mode: 355 1440 x 900 RandRScreen::loadSettings - adding mode: 380 2464 x 900 RandRScreen::loadSettings - adding crtc: 344 RandRScreen::loadSettings - adding output: 345 Setting CRTC 344 on output "default" (previous 0 ) CRTC outputs: (345) Output name: "default" Output refresh rate: 50 Output rect: QRect(0,0 2464x900) Output rotation: 1 XRandROutputs::init added output 345 adding an output 0 with geom: QRect(0,0 1440x900) adding an output 1 with geom: QRect(1440,0 1024x768) adding a disconnected output 2 adding a disconnected output 3 output: "SCREEN-0" QRect(0,0 1440x900) 208 false false output: "SCREEN-1" QRect(1440,0 1024x768) 10086976 false false output: "SCREEN-2" QRect(0,0 0x0) 2097268 true false output: "SCREEN-3" QRect(0,0 0x0) 2097268 true false load xml connected: 2 looking for current "SCREEN-0" known "*" has score: 0.125 known "*" has score: 0.125 looking for current "SCREEN-1" known "*" has score: 0.125 screen: 0 QRect(0,0 1440x900) screen: 1 QRect(1440,0 1024x768) looking for a matching configuration... connected: 2 looking for current "SCREEN-0" known "*" has score: 0.125 known "*" has score: 0.125 looking for current "SCREEN-1" known "*" has score: 0.125 found outputs, known: false activate external configuration!! registered the service: true screens registered on the bus: true outputs registered on the bus: true configurations registered on the bus: true In turn, as expected, it now doesn't detect when I disconnect the second screen. I just saw that Qt 4.6 introduced a new signal QDesktopWidget::screenCountChanged(), which might have also changed the semantics of the signal QDesktopWidget::resized(int)... Could you try whether also connecting to that signal in desktopwidgetoutputs.cpp on line 70 fixes things? Connecting to QDesktopWidget::screenCountChanged() indeed causes DesktopWidgetOutputs::screenChanged(int) to be called (which isn't the case without connecting). Unfortunately that isn't enough. While Kephal detects adding screens it still doesn't detect removing them. If I'm not mistaken this has something to do with the isVirtual variable. When I disconnect my second screen QDesktopWidget::isVirtualDesktop() returns false (has this also changed in Qt 4.6?). Therefore the following for-loop is never executed and the output isn't removed. Removing the if(isVirtual) check seems to fix it but I'm not sure that's the correct thing to do, although it seems to work correctly for me. Thank you for your bug report or feature request. Unfortunately, we did not have a maintainer for the "kephal" component, which is used to manage displays and monitors in the KDE Workspaces. The "kephal" component has been superseded by "KScreen" in newer releases of the KDE Workspaces. It is compatible with all versions since 4.11, and is also used with Plasma 5. Please check with your distribution how to update to KScreen. If this issue or feature request is still applicable to KScreen version 1.0.5 or newer, please add a comment. We will then reassign this ticket to KScreen developers. If you are already using KScreen to manage displays or monitors, and found a different bug or need a specific feature, please create a new ticket for "KScreen" product in this bugzilla using this link: https://bugs.kde.org/enter_bug.cgi?product=KScreen (This is an automatic message from the KDE Bug Triaging Team) |