Crash when launch / freeze when stages' preferences change

  • Tech Staff


    As mark has mentioned, this seems like an issue related to the "shared open GL resources" feature.
    I would suggest opening a new Isadora file, and setting this setting unchecked. It is found in the Isadora preferences in the OpenGL section of the Video tab.
    Then create a patch that is using all the outputs. As noted you will have to set the output stage at the beginning of the patch (eg: MoviePlayer)
    Additionally, you are not able to mix video streams with different destinations set (stage 1 VS stage 2)
    This setup/test file should allow you to determine if this setting is the cause of your troubles. 
    If you have further trouble, please submit a support request, and one of us will be happy to work with you to get the best possible performance from your system.
    The link for submitting a support request is available in my forum signature below.

  • Thanks for these informations !

    I can't believe it's not possible to adress one movie player to different stages ; how is it possible ? My movie player has to send the left half of the picture to stage 1 and the right half to stage 2 which are two separate videoprojectors. How can I do so ?

    Yes the first bug I had was linked to "shared open GL ressources" but I have unchecked it a long time ago.
    Now the problem is this : only the fact of launching Isadora with stage 1, stage 2 and stage 3 all active ("place on" set on display 1, 2 and 3) makes it crash (more precisely it makes it real slow, cycles fall at 30).

    I was told by someone else it could be linked to the fact that the videoproject that I suspect being the problem loses its numerical adress (it is linked to the computer by an DVI-I / VGA adapter and a VGA jack). Can it be this ?
    Are there any device to not fail on this ?

    I am looking for your answer, but if you don't see the problem, I'm going to create a support request, that's ok.
    Thanks for your attention

  • Dear @loulight,

    Before we go further, can you try working with the v2.5 advance beta to see if you can turn on "Shared OpenGL Resources" – I would like you to work with this version from this point forward because then – if we find a bug – I can include it in the next build and we can get you a new version quickly
    As I said previously, for Isadora to send this to two outputs, the image must be on the same GPU, i.e., the same graphics card. The problem you are experiencing is because you have two graphics cards. Isadora does what it can to share the images between two physical cards. But if the cards are, for instance, from two different manufacturers, this isn't possible. Now, I've tested this code on a machine I have back in Berlin, and it did successfully share the textures. But there are many reasons why this sharing might fail, and since not very many users try to use this possibility, it might explain why Isadora is crashing/freezing.
    Unfortunately, I am away from Berlin right now, and only have my laptop. So I will not be able to attempt tests on this until I get back next week.
    The inability to share textures is not an Isadora specific problem. If you want to see lots of references to it on the web, enter this into Google
    sharing textures multiple video cards
    or have a look at this NVIDIA article on the topic
    The simplest possible solution is upgrading to a single video card with multiple outputs. Is this something you can do? If so, then you will be able to turn on "Shared OpenGL Resources" and I feel confident all of these problems will go away. I don't think you'll have to invest a lot of money to get such a card, but I am not a PC expert. 
    @DusX – do you have a suggestion for inexpensive graphics cards that offer at least two outputs?
    Best Wishes,

  • Tech Staff

    I am not sure of the specs you require, but a graphics card that is a year or two backs model will provide a lot of power.
    I was very happily running the early Isadora beta on a nvidia gtx 640m sometime back, and found I could run 3 displays (th2go) with lots of GPU effects without a problem.
    Below are a couple cards for under $200. 
    The first is a 700 series and the second is from the 900 series (the series before the most recent from nvidia)

    note: its a Canadian site, so the prices are in CAD... they will be less in USD

    and the newer:

  • Hi,

    @mark , can you precise one thing about this shared ressource question :
    Is it a problem to have 2 stages on one graphic card displaying a "splitted movie", and the desktop & isadora control screen on an other gpu ?

  • Dear Mehdi,

    In theory, the you should be able to have the two stages on one graphics card and the Isadora main window on a second one. But, for instance, opening IzzyMap editor on that separate video card will then have the same problem, because it will want to share the textures on GPU 1 with the IzzyMap screen which will be on GPU 2.
    That being said, I haven't tried this. So you'd have to try it yourself to see how it works. (I don't have a setup handy to try it myself.)
    Best Wishes,

  • Hi,

    Was far from networks during last week but I'm back.
    Thanks for these advices, I will be able to make some tests with the entire dispositive on the 14th of September.

    *** Just one thing to precise :
    until here my config was this one :

    • first graphic card : isadora control screen (desktop) + one videoprojector
    • second graphic card : two videoprojectors

    The both graphic cards are the same (Radeon R7 360) :

    If I uncheck the "shared openGL ressources" there shouldn't be a problem isn't it ? Even if I send one movie to the VP on the first gpu and a splitted movie to the both VPs on the second gpu ?
    Until here I've been using VGA for all my outputs (through DP/VGA adapter and DVI-I/VGA adapter), but on each gpu I also have a "HDMI output". Do you think the problem could be fixed if I used this to put the videoprojector that is on my first graphic card on the second graphic card ? That would give :

    • first gpu : isadora control screen (desktop) in VGA
    • second gpu : two videoprojectors in VGA + one videoprojector in HDMI
      It looks like it could make the setup more stable for Isadora doesn't it ?


  • Just a remind to know if you have answers about my last post


  • Tech Staff


    unchecking the "shared openGL resources" should allow everything to run correctly 
    Note that the way you build a patch will change. You will define the stage number at the source, not the projector. And you can't use a source with multiple stage targets.
    As for moving the display from one card to the other, this configuration is currently untested, and may have the same limitations. (see marks note about Izzymap)

  • Hi,

    I finally could retest everything and it looks like things are going better.

    @Mark : I've tested the bêta version of Isa you sent me on August 20 - Isadora 2.4.5b04 - to see if the "Shared OpenGL Ressources" could now be activated. No it doesn't work, I've got the same problems on Isadora's launching. Half of the attempts end up by a crash...

    Concerning my problem of Isadora going really slow when I activate my three videoprojectors in Preferences/Stages : I've checked the option "Disable Vertical Retrace Sync" and the problem suddenly disappears. So my patch is working now.

    Until here, the fact of sending a splitted movie towards different stages doesn't cause troubles so I hope to be able to let my big patch as it is...

    Best regards