Auto-set artist.mouseover based on if get_cursor_data is overridden.

anntzer · anntzer · commit d174bb036731 · 2020-05-10T00:33:29.000+02:00
artist.mouseover marks whether the artist should be queried for custom
cursor data; right now it is only set for images.  In practice it can
default to being auto-set for artists that override get_cursor_data (if
they don't there's no point of querying them for cursor data, and if
they do then get_cursor_data should typically return something
interesting, but it's still fine if they return None).
diff --git a/lib/matplotlib/artist.py b/lib/matplotlib/artist.py
@@ -85,7 +85,9 @@ def __init__(self):
         self._contains = None
         self._rasterized = None
         self._agg_filter = None
-        self._mouseover = False
+        # Normally, artist classes need to be queried for mouseover info if and
+        # only if they override get_cursor_data.
+        self._mouseover = type(self).get_cursor_data != Artist.get_cursor_data
         self.eventson = False  # fire events only if eventson
         self._oid = 0  # an observer id
         self._propobservers = {}  # a dict from oids to funcs
diff --git a/lib/matplotlib/image.py b/lib/matplotlib/image.py
@@ -241,7 +241,6 @@ def __init__(self, ax,
                  ):
         martist.Artist.__init__(self)
         cm.ScalarMappable.__init__(self, norm, cmap)
-        self._mouseover = True
         if origin is None:
             origin = mpl.rcParams['image.origin']
         cbook._check_in_list(["upper", "lower"], origin=origin)
