Taking OpenGL Fullscreen with Cocoa
7 months ago — 4 Comments — Permalink
This is a quick how-to on dynamically making a Cocoa OpenGL view fullscreen. It’s pretty simple really - when the user initiates fullscreen, we call a method on our view which creates a new borderless window on top of all other windows and sets the contents to be our view. For this, I’m going to go ahead and assume that you have created a custom OpenGLView and have instantiated it in a regular NSWindow.
We’ll start off by adding a few variables to the view interface. These will allow us to keep track of the non-fullscreen starting window and our newly created fullscreen window, as well as which state we are in. It is important to keep track of the starting window so that we know where to restore the view to when switching away from fullscreen.
@interface MyOpenGLView : NSOpenGLView { NSWindow *fullscreenWindow; NSWindow *startingWindow; BOOL fullscreenOn; } @property (assign) IBOutlet NSWindow *startingWindow; - (IBAction) toggleFullscreen:(id)sender;
Now, in the implementation we synthesize startingWindow so that we have access to it:
@synthesize startingWindow;
Also in the implementation, the toggleFullscreen method should look something like this:
- (IBAction) toggleFullScreen:(id)sender { if( fullscreenOn == true ) { [fullscreenWindow close]; [startingWindow setAcceptsMouseMovedEvents:YES]; [startingWindow setContentView: self]; [startingWindow makeKeyAndOrderFront: self]; [startingWindow makeFirstResponder: self]; fullscreenOn = false; } else { NSRect frame = [[NSScreen mainScreen] frame]; // Instantiate new borderless window fullscreenWindow = [[NSWindow alloc] initWithContentRect:frame styleMask:NSBorderlessWindowMask backing:NSBackingStoreBuffered defer: NO]; [startingWindow setAcceptsMouseMovedEvents:NO]; if(fullscreenWindow != nil) { // Set the options for our new fullscreen window [fullscreenWindow setTitle: @"Full Screen"]; [fullscreenWindow setReleasedWhenClosed: YES]; [fullscreenWindow setAcceptsMouseMovedEvents:YES]; [fullscreenWindow setContentView: self]; [fullscreenWindow makeKeyAndOrderFront:self ]; // By setting the window level to just beneath the screensaver, // only this window will be visible (no menu bar or dock) [fullscreenWindow setLevel: NSScreenSaverWindowLevel-1]; [fullscreenWindow makeFirstResponder:self]; fullscreenOn = true; } else { NSLog(@"Error: could not create fullscreen window!"); } } }
We can now tie everything together in Interface Builder by hooking up the startingWindow outlet to our main window:
And finally, create a menu option which we hook up to the toggleFullscreen action of our view:
Save, rebuild and enjoy fullscreen goodness!
