message: fixed the input example, so that it works even when the logical and physical window size don't match;
  also added some explanation, since users should be aware that they may need to think about such things;
diff: @@ -65,10 +65,15 @@ impl event::EventHandler for MainState {
  println!("Mouse button released: {:?}, x: {}, y: {}", button, x, y);
  }
  - fn mouse_motion_event(&mut self, _ctx: &mut Context, x: f32, y: f32, xrel: f32, yrel: f32) {
  + fn mouse_motion_event(&mut self, ctx: &mut Context, x: f32, y: f32, xrel: f32, yrel: f32) {
  if self.mouse_down {
  - self.pos_x = x;
  - self.pos_y = y;
  + // Mouse coordinates are PHYSICAL coordinates, but here we want logical coordinates
  + // so we need to divide through the scale factor.
  + // In more advanced/realistic scenarios you may need to calculate the logical coordinates
  + // using ggez::graphics::screen_coordinates.
  + let scale_f = graphics::window(ctx).scale_factor() as f32;
  + self.pos_x = x / scale_f;
  + self.pos_y = y / scale_f;
  }
  println!(
  "Mouse motion, x: {}, y: {}, relative x: {}, relative y: {}",
  