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QOpenGLWidget no longer "paintGl"...

  • This is fun. Anyway, my openGL widget decided to no longer call paintGL... I have literally no idea what to do. What do I do ?

    How do I even trouble shoot it ?

    The openGLWidget is just black.

    Not only that... every other openGL app I did is also black! What on earth is goin on...


    EDIT. if I force paintOpenGl. it paints, its as if I managed to globally disable even loop for openglwidget... O_O

  • Lifetime Qt Champion


    Does the same happen with one of Qt OpenGL examples ?

  • @SGaist OMG they broke too !!!

    Cube example is black.

    boxes say :-1: error: This example requires Qt to be configured with -opengl desktop Woah ! I've read on it, but I also read that qt is made with angle and I'd have to recompile it fro mscratch to run under that.

    This is crazy, everything worked for 1 year and now all is broken... OH my ! I installed 5.12.3 to start testing it, did that break up my openGl?! :- (((( I've uninstalled it yesterday and went back to 5.12.0 but looks like its all broken :- (

    More to that, this is getting more nuts.

    So I now set a timer and call paintGL to get it paiting, I cant call update() because it does nothing!

    Not only that, since my widget is inside a dockwidget, every time I detach-reattach the widget/ change its location. Entire widget gets wiped-reinitialized from scratch!!! :OOOOOOOO

    I've uninstalled QT & reinstalled latest version. Now I get.

    			FATAL: ASSERT: "ctx && fbo" in file kernel\qopenglwidget.cpp, line 872
     (kernel\qopenglwidget.cpp:872, (null))

    Some progress... I managed to "see" my openGL widget, esentially I did not add it to any layout, just did widget->show().
    However, if I add it to QDockWidget, when I drag the dock widget, my openGL widget gets destroyed. Its priceless, is that a feature? :- ) How do I disable it? ^^

    Edit 3
    Ok its a can of worms. I need to re-think my entire openGL implementation. I guess I should have parented it tothe right widget at the start and not just have it floating around during R&D process. Now the entire idea is broken sigh.

  • Lifetime Qt Champion

    Qt now has dynamic backend selection so you can tell your application which one to use.

    Did you had any Windows / Graphics Card driver update ?

  • @SGaist I've updated qt to latest and drivers. Everything "slowly" started to work again... magic...

  • Lifetime Qt Champion

    What do you mean by "slowly" ?

  • @SGaist Just that apps started to render again. No idea why, I guess a full driver/qt reinstall did trigger something and made it all work.

  • Lifetime Qt Champion

    Good !

    Then please mark the thread as solved using the "Topic Tools" button so that other forum users may know a solution has worked :)

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