The code sample below shows how an X Window System OpenGL program uses GLX visual/pixel formatting functions.
/* X globals, defines, and prototypes */
Display *dpy;
Window glwin;
static int attributes[] = {GLX_DEPTH_SIZE, 16, GLX_DOUBLEBUFFER, None};
/* find an OpenGL-capable Color Index visual with depth buffer */
vi = glXChooseVisual(dpy, DefaultScreen(dpy), attributes);
if (vi == NULL) {
fprintf(stderr, "could not get visual\n");
exit(1);
}
The Visual can be used to create a window and a rendering context.