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Creating an OpenGL View Without an Interface

So, I'm trying to create an openGL view (in my window). Im making a Cocoa app. Ive managed to create one through Interface Builder, but for educational purposes I want to continue and make one without it. Only on papers.

And here is the point that tells you that I am struggling with this. So what ive has basically done is still: I created a new class, "MyOpenGLView.h / m", inheriting from NSOpenGLView. I did not add any private vars or methods for it just the class name. The only thing I did was override initWithFrame: (by adding self = [super initWithFrame: pixelFormat:] to it). I read about it on the Internet so that you first create an instance of this file before it can be used). here is the code:

- (id) initWithFrame:(NSRect)frameRect
{
 NSOpenGLPixelFormat *pixelFormat = [[NSOpenGLPixelFormat alloc]
                                    initWithAttributes:(NSOpenGLPixelFormatAttribute[])
                                    {
                                    NSOpenGLPFAWindow,
                                    NSOpenGLPFADoubleBuffer,
                                    NSOpenGLPFADepthSize, 32,
                                    nil
                                    }];
 self = [super initWithFrame:frameRect pixelFormat:pixelFormat];
 [[self openGLContext] makeCurrentContext];
}

, "MyViewController.h/m", ? MyOpenGLView * myView. .m - :

myView = [[MyOpenGLView alloc] initWithFrame:CGRectMake(0,0,100.0,100.0)];
if (!myView) { NSLog(@"ERROR"); }

, , .

openGL-. , - , .. im not sure. ?

+4
2

, init . -.

@implementation AppDelegate

@synthesize window = _window;
@synthesize view = _view;

- (void)applicationDidFinishLaunching:(NSNotification *)aNotification {
    NSRect mainDisplayRect = [[NSScreen mainScreen] frame]; // I'm going to make a full screen view.

    NSOpenGLPixelFormatAttribute attr[] = {
        NSOpenGLPFAOpenGLProfile, NSOpenGLProfileVersion3_2Core, // Needed if using opengl 3.2 you can comment this line out to use the old version.
        NSOpenGLPFAColorSize,     24,
        NSOpenGLPFAAlphaSize,     8,
        NSOpenGLPFAAccelerated,
        NSOpenGLPFADoubleBuffer,
        0
    };

    NSOpenGLPixelFormat *pix = [[NSOpenGLPixelFormat alloc] initWithAttributes:attr];
    self.view = [[OpenGLViewCoreProfile alloc] initWithFrame:mainDisplayRect pixelFormat:pix];

    // Below shows how to make the view fullscreen. But you could just add to the contact view of any window.
    self.window = [[NSWindow alloc] initWithContentRect:mainDisplayRect
                                              styleMask:NSBorderlessWindowMask 
                                                backing:NSBackingStoreBuffered 
                                                  defer:YES];

    self.window.opaque = YES;
    self.window.hidesOnDeactivate = YES;
    self.window.level = NSMainMenuWindowLevel + 1; // Show window above main menu.
    self.window.contentView = self.view;
    [self.window makeKeyAndOrderFront:self]; // Display window.
}

@end

-makeCurrentContext -prepareOpenGl. , , , . CVDisplayLink , openGLview

// This is the callback function for the display link.
static CVReturn OpenGLViewCoreProfileCallBack(CVDisplayLinkRef displayLink,
                                              const CVTimeStamp* now, 
                                              const CVTimeStamp* outputTime, 
                                              CVOptionFlags flagsIn, 
                          CVOptionFlags *flagsOut, 
                                              void *displayLinkContext) {
    @autoreleasepool {
        OpenGLViewCoreProfile *view = (__bridge OpenGLViewCoreProfile*)displayLinkContext;
        [view.openGLContext makeCurrentContext];
        CGLLockContext(view.openGLContext.CGLContextObj); // This is needed because this isn't running on the main thread.
        [view drawRect:view.bounds]; // Draw the scene. This doesn't need to be in the drawRect method.
        CGLUnlockContext(view.openGLContext.CGLContextObj);
        CGLFlushDrawable(view.openGLContext.CGLContextObj); // This does glFlush() for you.

        return kCVReturnSuccess;
    }
}

- (void)reshape {
    [super reshape];
    CGLLockContext(self.openGLContext.CGLContextObj);

    ... // standard opengl reshape stuff goes here.

    CGLUnlockContext(self.openGLContext.CGLContextObj);
}

- (void)prepareOpenGL {
    [super prepareOpenGL];

    [self.openGLContext makeCurrentContext];
    GLint swapInt = 1;
    [self.openGLContext setValues:&swapInt forParameter:NSOpenGLCPSwapInterval];

    CGLLockContext(self.openGLContext.CGLContextObj);

    ... // all opengl prep goes here

    CGLUnlockContext(self.openGLContext.CGLContextObj);

    // Below creates the display link and tell it what function to call when it needs to draw a frame.
    CVDisplayLinkCreateWithActiveCGDisplays(&_displayLink);
    CVDisplayLinkSetOutputCallback(self.displayLink, &OpenGLViewCoreProfileCallBack, (__bridge void *)self);
    CVDisplayLinkSetCurrentCGDisplayFromOpenGLContext(self.displayLink, 
                                                      self.openGLContext.CGLContextObj, 
                                                      self.pixelFormat.CGLPixelFormatObj);
    CVDisplayLinkStart(self.displayLink);
}
+7

OpenGL, , , , initWithFrame self.

initWithFrame Nil. ( initWithFrame OpenGL).

+2

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