objective-copengl-3nsopenglviewnsopengl

OpenGL 3.2 w/ NSOpenGLView


How would I create a core profile in a custom implementation of NSOpenGLView? Which method should I override and what code should I put there?

So far I have this code:

// Header File
#import <Cocoa/Cocoa.h>

@interface TCUOpenGLView : NSOpenGLView

@end

// Source File
#import "TCUOpenGLView.h"
#import <OpenGL/gl.h>

@implementation TCUOpenGLView

- (void)drawRect:(NSRect)dirtyRect {
    glClear(GL_COLOR_BUFFER_BIT);
    glFlush();
}

@end

Solution

  • Apple has a sample code project called GLEssentials that shows exactly how to do this (note that it is a Mac OS X and iOS sample code project).

    Essentially you will need to subclass NSOpenGLView (the NSGLView class in the sample code) and implement the awakeFromNib method using the following:

    - (void) awakeFromNib
    {   
        NSOpenGLPixelFormatAttribute attrs[] =
        {
            NSOpenGLPFADoubleBuffer,
            NSOpenGLPFADepthSize, 24,
            // Must specify the 3.2 Core Profile to use OpenGL 3.2
            NSOpenGLPFAOpenGLProfile,
            NSOpenGLProfileVersion3_2Core,
            0
        };
    
        NSOpenGLPixelFormat *pf = [[[NSOpenGLPixelFormat alloc] initWithAttributes:attrs] autorelease];
    
        if (!pf)
        {
            NSLog(@"No OpenGL pixel format");
        }
    
        NSOpenGLContext* context = [[[NSOpenGLContext alloc] initWithFormat:pf shareContext:nil] autorelease];
    
        [self setPixelFormat:pf];
    
        [self setOpenGLContext:context];
    }
    

    Also remember that if you use any OpenGL API calls that have been removed from the 3.2 API your app will crash. Here is a PDF document of the 3.2 spec so you can see the changes.