objective-ciosglkit

Nested GLKView and GLKViewController


I'm new to OpenGL ES and I'm experimenting with GLKit. My goal is to develop a very simple app just to get a good feel of OpenGL.

I started with Apple's sample code (OpenGL ES game) and I implemented basic gesture controls: panning, zooming, rotating (trackball algorithm).

Now that this is done, I wanted to play with the different projection matrices and I started to design a user interface to do just that:


(source: canardpc.com)

The only problem is that it doesn't work when the top view in a GLKViewController isn't a GLKView.

Is it possible to have a GLKView as a subview and still retain the cool features of GLKViewController?

Thank you.


Solution

  • Ok so I found the answer.

    The "OpenGL View Controller" in the picture must be a normal UIViewController. Subclass this view controller and in the viewDidLoad, create programmatically your OpenGL View Controller:

    - (void)viewDidLoad
    {
        [super viewDidLoad];
    
        _openGLViewController = [[FZIOpenGLViewController alloc] initWithNibName:@"FZIOpenGLView" bundle:nil];
    
        _openGLViewController.view.frame = _openGLView.frame;
    
        [self.view addSubview:_openGLViewController.view];
    
    }
    

    In this code, _openGLView is an IBOutlet representing "GLKit View" in the picture. It's basically just there to get the right dimensions.

    _openGLViewController is your GLKViewController subclass that handles everything OpenGL. The .xib file FZIOpenGLView.xib is just a GLKView with the appropriate File Owner (FZIOpenGLViewController).

    It works:

    result
    (source: canardpc.com)