NSGL: Failed to create OpenGL pixel format - opengl

Question

My code is here, this returns an error: NSGL: Failed to create OpenGL pixel format
the error callback is the standard callback from glfw.
int main(int argc, const char * argv[]) {
glfwSetErrorCallback(error_callback);
if (!glfwInit ()) {
fprintf (stderr, "ERROR: could not start GLFW3\n");
return 1;
}
GLFWwindow* window = glfwCreateWindow (640, 480, "Hello Triangle", NULL, NULL);
glfwMakeContextCurrent (window);
if (!window) {
fprintf (stderr, "\nERROR: could not open window with GLFW3\n");
return -1;
}
// start GLEW extension handler
glewExperimental = GL_TRUE;
glewInit ();
// get version info
const GLubyte* renderer = glGetString (GL_RENDERER); // get renderer string
const GLubyte* version = glGetString (GL_VERSION); // version as a string
printf ("Renderer: %s\n", renderer);
printf ("OpenGL version supported %s\n", version);
// tell GL to only draw onto a pixel if the shape is closer to the viewer
glEnable (GL_DEPTH_TEST); // enable depth-testing
glDepthFunc (GL_LESS); // depth-testing interprets a smaller value as "closer"
/* OTHER STUFF GOES HERE NEXT */
// close GL context and any other GLFW resources
glfwTerminate();
return 0;
}
does someone know what the problem is?

Answer 1

On my OSX Machine, that issue arised due to the stencil buffer depth setting, which was 16 bit. OSX appearently (or the built in graphics cards) can only handle 8 bit. Since I´m not into OpenGL at all, I cannot reason this yet, but I will update the answer as soon as I have a deeper understanding.
The code responsible for setting the buffer depth is the following (corrected version):
glfwWindowHint(GLFW_STENCIL_BITS, 8);
which is executed before creating the window with glfwCreateWindow(...)
Hope this helps :)