Display updates intermittent

Home Forums AR Sandbox Forum Display updates intermittent

Viewing 9 posts - 1 through 9 (of 9 total)
  • Author
  • #100795

    Hi Oliver,

    Everything is working except: The display does not update unless I move the mouse or press a key.
    This happens regardless of using RawKinectView or CalibrateProjector. I’ve tried this on 2 different laptops, one with a Radeon screen card and one with an Intel screen card, the drivers are updated.

    I do get GL errors on the laptop with the Intel card, but I’m assuming it might be because the card does not have hardware acceleration, so I’m ignoring them.

    I am going to experiment with open source drivers iso proprietary drivers but any additional help would be appreciated.


    Oliver Kreylos

    I’ve heard about that problem a few times now, but I’ve never been able to replicate it, or figure out what could be causing it.

    Does the same happen when you run one of the non-Kinect / Sandbox Vrui applications, such as the ShowEarthModel one that’s part of Vrui’s example programs?

    Oliver Kreylos

    One thing: what kind of laptops did you try, and how old were they?

    I have a 2008 Macbook Pro, and I have run into a similar issue with Kinect. The moment I stop moving the mouse/trackpad or stop pressing keys, the computer goes into a lower-power state, and in that state it’s not fast enough to keep up with the Kinect’s high data transmission rate. Plugging it into an AC outlet, or turning off power saving in laptop mode, fixes the issue. Have you by any chance tried any of that?


    Ho Oliver,

    I’ve only tested the ShowEarthModel and that seems to be working fine. It does not freeze up.

    The 2 PC’s I’ve tried it on is a an Acer 6592G and a HP ProBook 450, both running an Ubuntu and Windows as a dual boot system.

    I have decided to stick to the HP and all the tests are now done on it:
    1) Only uses AC,
    2) Disabled all the CPU stepping features (it was enabled). The problem changed from being constant to being intermittent to the point where it works , it did not really make a big improvement,
    3) HW acceleration is enabled and drivers are updated

    What I have seen:
    1) The problem is now intermittent mostly to the point of it being usable and if it is does freeze, a quick movement of the mouse unfreezes the screen.
    2) It sometimes get ‘stuck on’ working and then even if after coming out of the screen saver, it will still be working and updating the screen fine.
    3) If any button is pressed, right after launch, without clicking the mouse first, the program quits with an error
    4) Clicking the mouse, or moving on the track-pad, after the screen froze, mostly gets it unstuck
    5) I still get the GL error as outputs on the terminal when quitting the sandbox program

    Oliver Kreylos

    Thanks for the detailed report. This seems to be a USB issue. RawKinectViewer, KinectViewer, CalibrateProjector, SARndbox all run in event mode, where they only force a screen update if a new image arrives from the Kinect. If the Kinect stops sending for some reason, the software won’t refresh the screen unless you move the mouse or press a key, which always forces a refresh.

    Most laptops (including mine) have a lot more detailed power savings methods than what is exposed via the control GUIs. Most pertinently, they tend to put USB ports to sleep if they consider the computer “unused.” I think this is what’s happening. User doesn’t touch computer -> OS thinks it’s unused -> USB goes to sleep -> no more data from Kinect -> no more display updates -> mouse move forces screen refresh and wakes up OS and USB ports -> Kinect sends data again.

    I’ll need to look into a fix.

    3) If any button is pressed, right after launch, without clicking the mouse first, the program quits with an error

    That’s unfortunately a known Vrui bug. After starting an application, first click the mouse inside its window before pressing any keys. It’s already fixed in the next version, but it isn’t out yet.

    Oliver Kreylos

    Here’s a potential and very ugly work-around. Open the Vrui.cfg configuration file inside your Vrui installation (~/Vrui-3.1/etc/Vrui.cfg) with a text editor, and directly after the lines “section Vrui” and “section Desktop,” insert a new line “updateContinuously true”, save the file, and then run RawKinectViewer et al. again. This might keep it running.

    Note that this fix will run the applications in polling mode, which will drain your battery in no time flat, and your computer will run hot. Don’t keep it in there for any extended period of time.

    Another option, if your computer keyboard has those keys, is to press “Win+Scroll Lock” while an application is running. This will go into “burn mode,” which is the same thing, until you press the key combo again.


    This sounds like a problem I am having also, except with SARndbox. I am running the sandbox every day for hours at a time. Sporadically, several time a day, the sandbox just freezes. Movement of the mouse will allow it to run but only for a few seconds.

    Usually I have to reboot to make it start again. If I simply stop and restart SARndbox I usually get an error “startStreaming: Failed to disable cameras”.
    Is it possible this indicates a problem with the Kinect?

    I will try some of the things mentioned above to help keep it going. I thought this might help to better understand the freezing problem in general.

    Thanks, Gary



    We built a SARndbox today and had the same problem when the water simulation was set to 0.0 0. Once I turned the water simulation on it updated normally.




    Are there any updates on it?
    I have encountered the same issue mentioned above.


Viewing 9 posts - 1 through 9 (of 9 total)
  • You must be logged in to reply to this topic.

Comments are closed.