+ fn compute_extra_draws_from_total_update_rects(&mut self) {
+     for full_redraw_dirty_rect in full_redraw_dirty_rects.iter() {
+         for elem in self.compositor_state.elements.iter() {
+            for visible_region in elem.drawable_rects().iter() {
+                let intersection = visible_region
+                    .area_overlapping_with(full_redraw_rect)
+                    .unwrap();
+                self.compositor_state
+                    .queue_extra_draw(Rc::clone(&elem), intersection);
+            }
+         }
+     }
+ }