NSOpenGLView toggle to fullscreen from within the view

Question

I'm trying to create a method that will toggle between fullscreen and a window. I'm trying to do this from within a class inherited from NSOpenGLView, essentially following this blogpost. That works once, going from windowed to fullscreen; trying to go back fails in various ways: the window screen doesn't get updated, or I don't even manage switch to the window but the fullscreen just blanks out. Trying to go back and forth a few times anyway (mapped it to the 'f' key), the program often locks up, and in a worst case, I have to restart my computer. I've attached the code for the method below; for debugging purposes, I've set the full frame rectangle much smaller, so that if things freeze, the application is never at full screen.

The fullscreen example in the Apple developer examples suggest using a controller, and does not go fullscreen from within the inherited NSOpenGLView.

My questions:

• should I use a controller instead, and from there switch between windowed and fullscreen (creating a separate fullscreen view each time)? Or should both methods work?
• If both methods should work, which one is preferred?
• If both methods can work, what am I doing wrong in the current way of implementing this?
• or, is there a third, better, method?

Note that for both references, I'll have to assume that things haven't changed for 10.8 (both references seem to apply to 10.6).

Code follows:

@implementation MyOpenGLView

[...]

- (void)toggleFullscreen
{
    mainWindow = [self window];

    if (isFullscreen) {
        [fullscreenWindow close];
        [mainWindow setAcceptsMouseMovedEvents:YES];
        [mainWindow setContentView: self];
        [mainWindow makeKeyAndOrderFront: self];
        [mainWindow makeFirstResponder: self];
        isFullscreen = false;
    } else {
        [mainWindow setAcceptsMouseMovedEvents:NO];
        //NSRect fullscreenFrame = [[NSScreen mainScreen] frame];
        NSRect fullscreenFrame = { {300, 300}, {300, 300} };
        fullscreenWindow = [[NSWindow alloc] initWithContentRect:fullscreenFrame
                                                       styleMask:NSBorderlessWindowMask
                                                         backing:NSBackingStoreBuffered
                                                           defer:NO];
        if (fullscreenWindow) {
            [fullscreenWindow setAcceptsMouseMovedEvents:YES];
            [fullscreenWindow setTitle:@"Full screen"];
            [fullscreenWindow setReleasedWhenClosed: YES];
            [fullscreenWindow setContentView: self];
            [fullscreenWindow makeKeyAndOrderFront: self];
            //[fullscreenWindow setOpaque:YES];
            //[fullscreenWindow setHidesOnDeactivate:YES];
            // Set the window level to be just above the menu bar
            //[fullScreenWindow setLevel:NSMainMenuWindowLevel+1];
            // Set the window level to be just below the screen saver
            [fullscreenWindow setLevel:NSScreenSaverWindowLevel-1];
            [fullscreenWindow makeFirstResponder:self];

            isFullscreen = true;
        } else {
            NSLog(@"Error: could not switch to full screen.");
        }
   }
}

[...]

@end

Answer 1

I now think this can't be done, and should not be done. When windowed, the rendering context is a window, which is a different beast than a screen, when rendering fullscreen. Thus, when switching between, things have to re-setup everytime you switch.

It is possible to simply use the native fullscreen option that is in the newest OS X variants. This will (presumably) enlarge the containg window to full screen size while removing the frame, borders and buttons. Thus, you're still rendering to a window, though it looks fullscreen.

I'm not sure if this option makes things slower: there's a window layer in between, which could make it a slower than rendering directly to a screen.

For the curious, implementing the native fullscreen is ridiculously easy (at least in 10.8 and 10.9): In XCode, select the .xib file, select the (main) window in the editor's sidebar, then select the attributes selector on the right. You can find a "Full Screen" selection between Unsupported, Primary Window or Auxiliary Window. That will automatically add the full screen toggle to the window. Even neater, now select the main menu -> view menu in the sidebar, find the "Full Screen Menu Item" in the inspector at the bottom (there's a search bar for it), drag it into the View menu in the editor, and voilà, it will have a shortcut and automatically connect to the full screen option for the window (select the new View menu item and look at the Connections inspector to it's already connected for you).

A nice way to test all this is to grab the full screen example I linked in my question, and edit it as suggested above. Using the default control-command F shortcut to toggle back and forth between fullscreen will show the opengl view and the frame with text below it in a full screen. Using the fullscreen option as coded in the example will toggle the openglview to use the fullscreen, without any extra (Cocoa) frames, buttons or text.

Answer 2

I'm curious about this too- specifically your first two bullet point questions.

This doesn't address those questions, but your third one about the bug, I think you can get away with just changing the properties of the same window (works for me):

- (void)toggleFullscreen
{
    if (isFullscreen) {
        NSRect windowFrame = [[NSScreen mainScreen] visibleFrame];
        [mainWindow setStyleMask:NSTitledWindowMask | NSClosableWindowMask |
                             NSMiniaturizableWindowMask | NSResizableWindowMask ];
        [mainWindow setFrame:windowFrame display:true];
        [mainWindow setAcceptsMouseMovedEvents:YES];
        [mainWindow setLevel:NSNormalWindowLevel];
        [mainWindow setTitle:@"SimpleOculus"];
        [mainWindow makeKeyAndOrderFront:self];
        [mainWindow makeFirstResponder:self];
        isFullscreen = false;
    }
    else {
        NSRect fullscreenFrame = [[NSScreen mainScreen] frame];
        [mainWindow setStyleMask:NSBorderlessWindowMask];
        [mainWindow setFrame:fullscreenFrame display:true];
        [mainWindow setAcceptsMouseMovedEvents:YES];
        [mainWindow setLevel:NSScreenSaverWindowLevel-1];
        [mainWindow makeKeyAndOrderFront:self];
        [mainWindow makeFirstResponder:self];
        isFullscreen = true;
    }
}