I wonder if running a loop as fast as possible - eg. for (;

{ Display.update(); } - on a grabbed mouse in Windows wouldn't actually be expecting this behaviour, actually, having just been monkeying around in the code. The mouse is recentered every update(), which if you're running it at 1600Hz, means it probably never gets to move, and the movement is how we currently get the delta values.
I think we need a better way to get mouse deltas than this.
I seem to recall a long time ago when I first had JGLIB/LWJGL early alphas we used DirectInput for the mouse. Maybe we should look into using it again for delta values on Windows.
Cas
