NSOpenGLView subclass not resizing with window

Question

I've been trying to get the NSOpenGLView to resize correctly when resizing the window, but I keep getting weird behaviour which I cannot explain. It looks like so:

Original (What it looks like at the beginning):

After resize:

This is my resize code:

- (void)reshape
{
    [super reshape];

    CGLLockContext([[self openGLContext] CGLContextObj]);

    NSRect viewRectPoints = [self bounds];

#if SUPPORT_RETINA_RESOLUTION

    NSRect viewRectPixels = [self convertRectToBacking:viewRectPoints];

#else //if !SUPPORT_RETINA_RESOLUTION

    NSRect viewRectPixels = viewRectPoints;

#endif // !SUPPORT_RETINA_RESOLUTION

    [self resizeWithWidth:viewRectPixels.size.width
                  AndHeight:viewRectPixels.size.height];

    CGLUnlockContext([[self openGLContext] CGLContextObj]);
}

- (void) resizeWithWidth:(GLuint)width AndHeight:(GLuint)height
{
    glViewport(0, 0, width, height);

    m_width = width;
    m_height = height;
}

and I'm using: "glViewport(0, 0, m_width, m_height);" whenever I call glDrawArrays();

Can anyone help?

can you post your drawRect function also? – Ronald S. Bultje Apr 19 '15 at 13:02 — Ronald S. Bultje, Apr 19 '15 at 13:02

score 1 · Answer 1 · answered Apr 04 '15 at 16:39

When resizing the window you should also set the projection matrix to reflect the new dimensions. You didn't post your setup/drawing code, but usually that looks something like:

glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluPerspective(...); // or glFrustum(), glOrtho(), gluOrtho2D(), ...
glMatrixMode(GL_MODELVIEW);

score 0 · Answer 2 · answered Aug 28 '15 at 18:29

Seriously, in these days you might want to consider to leave NSOpenGLView behind and move to CAOpenGLLayer directly.

I've had too many issues with this silly class to bother any more about NSOpenGLView and in layer backed views particularly having a CAOpenGLLayer IMHO just gives you more flexibility - and control.
(and less bugs - try getting NSOpenGLView to work in a layer backed view hierarchy under 10.9 or pre..).

Plus more functionality right out of the box - or at least under your finger tips (like built-in CVDisplayLink support).

Just my 2c.

NSOpenGLView subclass not resizing with window

2 Answers2