assimp model importing

-(void) setup3dObjectsWithThread
{
    /*
    dispatch_queue_t queue = dispatch_queue_create("", NULL);
    dispatch_async(queue, ^{
        //code to be executed in the background
        NSString* dataPath = [[NSBundle mainBundle] resourcePath];
        NSString * m1 = @"Apple.3ds";
        model1 = new REVuModel([dataPath UTF8String], [m1 UTF8String]) ;

        if(model1->isValid)
        {
            model1->TranslateTo(0, 0, 0);
            model1->ScaleUniformTo(0.4);
            model1->RotateTo(0, 0, 0);
            model1->Alpha(1.0);
            model1->SwitchLight(true);
        }

        dispatch_async(dispatch_get_main_queue(), ^{
            //code to be executed on the main thread when background task is finished
            NSLog(@"Ending Point of loading models %@ and start of main_queue", queue);
        });
    });*/

    NSThread* myThread = [[NSThread alloc] initWithTarget:self
                                                 selector:@selector(myThread_MainMethod:)
                                                   object:nil];
    [myThread start];
}

-(void) myThread_MainMethod:(id)sender
{
    NSString* dataPath = [[NSBundle mainBundle] resourcePath];
    NSString * m1 = @"Apple.3ds";
    model1 = new REVuModel([dataPath UTF8String], [m1 UTF8String]) ;

    if(model1->isValid)
    {
        model1->TranslateTo(0, 0, 0);
        model1->ScaleUniformTo(0.4);
        model1->RotateTo(0, 0, 0);
        model1->Alpha(1.0);
        model1->SwitchLight(true);
    }
}

REVuModel::REVuModel(const char *dataPath, const char * modelName)
{
    rootPath.Set(dataPath);
    rootPath.Append("/");
    aiString  modelPath = rootPath;
    modelPath.Append("/");
    modelPath.Append(modelName);

    scene = NULL;
    isValid = false;

    //DEFAULTS
    _scale = vec3(1.0 , 1.0, 1.0);
    _position = vec3(0.0, 0.0, 0.0);
    _rotation = vec3(kInitalRoation, 0.0, 0.0);
    _lightDirection = vec3(0.0, 0., -1.0); //FRONT & ABOVE
    _alpha =1.0;
    _customTexture = false;
    _customMaterial = false;

    Assimp::Importer* importer =  new Assimp::Importer();

    printf("\nASSIMP Version %i.%i.%i\n", aiGetVersionMajor(), aiGetVersionMinor(),aiGetVersionRevision());
    //printf("FREEIMAGE Version %s \n\n", FreeImage_GetVersion());

    scene = importer->ReadFile(modelPath.data,aiProcessPreset_TargetRealtime_MaxQuality);

    if(!scene || !initShaders())
    {
        isValid = false;
        printf("nASSIMP model loader: failed to load %s \n\n", modelName);
    }
    else
    {
        aiVector3D scene_min, scene_max;
        getBoundingBoxWithMinVector(&scene_min, &scene_max);

        normalizedScale = scene_max.x-scene_min.x;
        normalizedScale = aisgl_max(scene_max.y - scene_min.y,normalizedScale);
        normalizedScale = aisgl_max(scene_max.z - scene_min.z,normalizedScale);
        normalizedScale = 1.f / normalizedScale * 255; //????

        _scale = vec3(normalizedScale , normalizedScale, normalizedScale);
        loadGLResources();
        isValid = true;
        printf("nASSIMP model loader: %s loaded \n\n", modelName);
    }
}