macOS NSOpenGLView displays all white inside view

[bahlquist]

I have managed to get an NSOpenGLView subclass to work and have played around with it a bit. When I try to do the same in a new project, it doesn't work. Here is what I have done. I have a subclass of NSOpenGLView called BACubes. In interface builder, I drag an NSOpenGLView object from the palette into my window. I set its class to BACubes. Here is the code for BACubes:

BACubes.h:

#import <Cocoa/Cocoa.h>

@interface BACubes : NSOpenGLView {}
@end

BACubes.m:

#import "BACubes.h"
#include <OpenGL/gl.h>

@implementation BACubes

-(void)drawRect:(NSRect)rect{
	NSLog(@"hey");
    glClearColor(0,0,0,0);
	glClear(GL_COLOR_BUFFER_BIT);
}
	
@end

I expect to see a black view screen. The console shows that drawRect has been called. Can you tell me what's wrong?

 

[jared_kipe]

See if you get an error after glClear
You should probably set the 0's to 0.0's or 0.0f's

 

[bahlquist]

Thanks for your reply. This is not the problem. Whole numbers as arguments seem to be ok in general (I would be curious if it ever resulted in a problem).

 

[jvaneat]

Try adding this:

-(id) initWithFrame: (NSRect) frameRect
{
        NSOpenGLPixelFormatAttribute attribs[] =
        {
		kCGLPFAAccelerated,
		kCGLPFANoRecovery,
		kCGLPFADoubleBuffer,
		kCGLPFAColorSize, 24,
		kCGLPFADepthSize, 16,
		0
	};
	NSOpenGLPixelFormat * pf = [[NSOpenGLPixelFormat alloc] initWithAttributes:attribs];

	self = [super initWithFrame: frameRect pixelFormat: pf];
    return self;
}

 

[jared_kipe]

Thanks for your reply. This is not the problem. Whole numbers as arguments seem to be ok in general (I would be curious if it ever resulted in a problem).

I didn't expect it to be the problem. But if you know the type of the argument, you should type in the right type. It's just my defensive programmer sense.

 

[bahlquist]

Try adding this:

-(id) initWithFrame: (NSRect) frameRect
{
        NSOpenGLPixelFormatAttribute attribs[] =
        {
		kCGLPFAAccelerated,
		kCGLPFANoRecovery,
		kCGLPFADoubleBuffer,
		kCGLPFAColorSize, 24,
		kCGLPFADepthSize, 16,
		0
	};
	NSOpenGLPixelFormat * pf = [[NSOpenGLPixelFormat alloc] initWithAttributes:attribs];

	self = [super initWithFrame: frameRect pixelFormat: pf];
    return self;
}

I added this to my implementation, but it never gets called (I noticed this with my other projects and so I omitted any "init" method.)

Isn't it true that Interface Builder takes care of the initialization (as far as "double buffer" and such goes)?

 

[jared_kipe]

-initWithCoder:

 

[bahlquist]

I implemented initWithCoder instead of initWithFrame. The method is called, but I still get only a white rectangle.

 

[ncl]

Try adding [[self openGLContext] flushBuffer]; at the end of -drawRect