How to use Gdk::POINTER_MOTION_HINT_MASK?

[Robert Hildebrandt <roberts_katz gmx de>]

Hi,

I want to use the POINTER_MOTION_HINT_MASK Events within a DrawingArea. 
But it sends every time I move the mouse an event, as if it was a 
POINTER_MOTION_MASK Event. The only difference is, that event->is_hint 
is true.

Here's the Code:

#include <gtkmm.h>
#include <iostream>

struct MainWindow : public Gtk::Window
{
 Gtk::DrawingArea draw;
 MainWindow()
 {
   add(draw);
   draw.show();

   draw.add_events(Gdk::POINTER_MOTION_HINT_MASK | 
Gdk::POINTER_MOTION_MASK);
   
draw.signal_motion_notify_event().connect(sigc::ptr_fun(&MainWindow::on_move));
 }
 static bool on_move(GdkEventMotion* event)
 {
   if(event->is_hint)
   {
     std::cout<<"IS HINT\n"; // this is shown on the Console, every 
time I move the cursor
   }else
   {
     std::cout<<"IS NOT HINT\n";
   }
   return true;
 }
};

int main(int argc, char** argv)
{
 Gtk::Main main(argc, argv);

 MainWindow w;

 main.run(w);

 return 0;
}

Thank you in advance