Fix for issue #13478:

onatt · onatt · commit d405b1cc98f5 · 2019-02-22T14:07:16.000+01:00
In an animation using blitting that contains some static graphics elements, the static parts of the figure are not updated after an interactive zoom/pan event. However, they are correctly updated after an resize event.
diff --git a/lib/matplotlib/animation.py b/lib/matplotlib/animation.py
@@ -1222,6 +1222,14 @@ def _setup_blit(self):
         # axes
         self._blit_cache = dict()
         self._drawn_artists = []
+        def remove_from_cache(ax):
+            try:
+                del self._blit_cache[ax]
+            except KeyError:
+                pass
+        for ax in self._fig.axes:
+            ax.callbacks.connect('xlim_changed', remove_from_cache)
+            ax.callbacks.connect('ylim_changed', remove_from_cache)
         self._resize_id = self._fig.canvas.mpl_connect('resize_event',
                                                        self._handle_resize)
         self._post_draw(None, self._blit)
