Memory leak when changing scene (renderers)

[ribot]

Hi all, when I change my renderers (say from a game menu scene to the level 1 of the game), I receive the following output to the error stream:

2004-06-21 00:16:13.459 java[502] *** _NSAutoreleaseNoPool(): Object 0x931ce00 of class NSSurface autoreleased with no pool in place - just leaking

The following is my main application’s method for changing scenes:

  public static void changeScene(GLScene newJoglScene) {
        System.out.println("Main changeScene() start ===========");
        // Stop the rendering thread
        animator.stop();
        // Remove the Rendering canvas from the AWT frame
        frame.remove(currentScene.getCanvas());
        // Shut down and clean up all objects used with the scene
        currentScene.shutDown();

        // nullify the current JoglScene
        currentScene = null;
        
        // Copy the new Scene from the passed parameter object
        currentScene = newJoglScene;
        // should we remove the newJoglScene instance now? hmm, no.
        canvas = currentScene.startUp();
        frame.add(canvas);
        frame.show();
        animator = new FPSAnimator(canvas, FRAME_RATE);
        animator.start();
        System.out.println("Main changeScene() finish ===========");
        canvas.requestFocus();
  }

and the currentScene.shutDown() and currentScene.startUp() are as follows:

currentScene.startUp()

        canvas = GLDrawableFactory.getFactory().createGLCanvas(new GLCapabilities());
        // Add the rendering class
        canvas.addGLEventListener(renderer = new MenuRenderer(this));
        
        // add the listeners (custom internal classes)
        canvas.addMouseListener(this);
        canvas.addMouseMotionListener(this);
        canvas.addKeyListener(this);      

currentScene.shutDown()

        canvas.removeMouseListener(this);
        canvas.removeKeyListener(this);
        canvas.removeGLEventListener(renderer);
        renderer = null;
        canvas = null;

I’m sure that I’m just missing out one line, or have something a little mixed up. I’ve been through all the combinations of calls that I can think of, but always end up with the same memory leak.

I look forward to hearing any thoughts you may have!

[gziemski]

Cocoa uses object pools for autorelasing objects. On main cocoa thread there is a pool created for you automatically, but other threads need to create their own. It seems that we do things (pretty much anything using cocoa APIs) on a non cocoa thread that needs a release pool.

I’ll look into that.

cheers

[ribot]

Well, good news (I think)… I updated to Java 1.4.2 Update 1 Developer Preview 2 and the memory leak issue has now disappeared! I was a little hesitant to upgrade to this version, as the last time I upgraded to it - Java no longer worked and I had to reinstall the entire system - something which don’t have the time to do atm (although it would only take 3 or so hours to get everything back to normal).

Can’t wait to see what updates there will be in developer preview 3!