Popping SPViewController causes crash

membersheep

I recently updated from Sparrow 2.0.1 to the latest version on GitHub to take advantage of the new FragmentFilter feature (I'm stuck with the creation of my custom display object 🙁 ), but i immediately encountered a problem: in my project the sparrow view controller is pushed over other controllers which manage the UI. When i pop the controller, the app crashes while deallocating the SPViewController, exactly at "[SPContext setCurrentContext:nil];"
If i comment this line it doesn't crash but when pushing back the controller i see some problems in rendering (black rectangles). With Sparrow 2.0.1 it did not happen.
Is this a problem of my implementation? Did you ever try to pop a SPViewController (in the demo is used as root)?

Thanks

racarone

There's a bug in SPContext and the fix hasn't been merged yet. You can fix it by replacing these two methods in SPContext:

+ (BOOL)setCurrentContext:(SPContext *)context
{
    if (context && [EAGLContext setCurrentContext:context->_nativeContext])
    {
        currentThreadDictionary[currentContextKey] = context;
        return YES;
    }

    return NO;
}

+ (SPContext *)currentContext
{
    SPContext *current = currentThreadDictionary[currentContextKey];
    if (!current || current->_nativeContext != [EAGLContext currentContext])
        return nil;

    return current;
}

membersheep

I was figuring that out, but thank you very much! 😉

edit: I noticed it's the same modification that i made and it generates another bug
Here's the scene at the first load of the SPViewController:
http://imgur.com/F3TCp8d.png
And here's the scene after popping the controller and coming back pushing the controller again:
http://imgur.com/SZRiaNK.png

I tried also with sparrow-s, when i push back the controller the sparrow view is black, i see only the UIKit elements i put over it.

Daniel

Yesterday, I merged the bugfix mentioned by Rob into the master branch. Could you try if it works with that?

Daniel

Or wait, please give us another day: Rob recently replaced the complete GLKViewController with a better (and faster) implementation. It's very probable that this fixes it — and if not, Rob has all the source of that one and can more easily fix it with that version.

membersheep

Wonderful, I was monitoring sparrow-s branch and I saw he implemented 2 new classes that may affect the problem, so I already tried using sparrow-s, but with worse results (black screen when pushing back). I have to add new content to the app this afternoon, but when I'm done with that I'll keep on investigating the problem, even if my knowledge about sparrow codebase isn't nearly comparable to yours.

racarone

Try it again with the Sparrow-S master, I made some changes to the way SPView and SPViewController interact. I tried presenting and dismissing view controllers with the updated version and got no bugs or errors.

membersheep

Hi Rob, I'm testing Sparrow-s master right now and I got some crashes in glDrawElements, but the problem of popping and pushing the controller didn't go away, here's the error it returns:
Sparrow failed to make complete framebuffer object
Sparrow failed to make complete framebuffer object
There was an OpenGL error: GL_INVALID_ENUM
There was an OpenGL error: GL_INVALID_ENUM
(...keep printing this)
As usual the first load works fine, but after popping and pushing it shows black screen (except for uikit elements, not managed by sparrow)

Today I'll find some time to build a small test project for this issue!

membersheep

https://bitbucket.org/membersheep/spvctest/overview
here's a little repo with a test project, showing the problem i noticed. I hope this can help you! Sparrow-s latest master is included with source files.

racarone

I committed a fix for the blank screen on re-presenting the view controller, try it now. There must be a bug in EAGLContext...

membersheep

Good, now when I re-present the view controller it shows the textures without black parts, in my test project and in my app.
My app still throws "Sparrow failed to make complete framebuffer object" and "There was an OpenGL error: GL_INVALID_ENUM" when reloading the controller, and display objects do not change when I move-scale-remove-add them to the display tree.
It still crashes when I change page of my book even in the first run (i.e. removing some display objects and adding new ones, it didn't with sparrow 2.0.1), with this error http://i.imgur.com/ZqRtr3s.png
When the vc is reloaded and printing those OpenGL errors, the app doesn't crash when i change page (but also keeps stuck in the first page without any animation).
I think this might be caused by using multiple textures while in the test project i load just one, so it doesn't crash.
I will try to load more textures also in the test project and see what happens.
This is strange because when I "change page" i basically just removeAllChildren: from my game class, load the new page (a SPSprite filled with content), addChild: to present the new page, and reading the errors it seems something's wrong with quad batches.
Thank you again!

racarone

I haven't been able to reproduce this and it could any number of things. It most likely has nothing to do with SPQuadBatch, but errors out there do to a previous invalid state. You might have to make a more specific sample project showing what you're doing.

membersheep

I will do it asap!