code: func (v *GLContext) Realize() (bool, error) {
  	var err *C.GError
  	r := gobool(C.gdk_gl_context_realize(v.native(), &err))
  	if !r {
  		defer C.g_error_free(err)
  		return r, errors.New(C.GoString((*C.char)(err.message)))
  	}
  
  	return r, nil
  }
docs: // Realize is a wrapper around gdk_gl_context_realize().