Merge pull request matplotlib#25558 from anntzer/ic

Simplify outdated Image.contains check.

Author: greglucas

lib/matplotlib/image.py

@@ -654,14 +654,9 @@ def draw(self, renderer, *args, **kwargs):
 
     def contains(self, mouseevent):
         """Test whether the mouse event occurred within the image."""
-        if self._different_canvas(mouseevent):
-            return False, {}
-        # 1) This doesn't work for figimage; but figimage also needs a fix
-        #    below (as the check cannot use x/ydata and extents).
-        # 2) As long as the check below uses x/ydata, we need to test axes
-        #    identity instead of `self.axes.contains(event)` because even if
-        #    axes overlap, x/ydata is only valid for event.inaxes anyways.
-        if self.axes is not mouseevent.inaxes:
+        if (self._different_canvas(mouseevent)
+                # This doesn't work for figimage.
+                or not self.axes.contains(mouseevent)[0]):
             return False, {}
         # TODO: make sure this is consistent with patch and patch
         # collection on nonlinear transformed coordinates.
@@ -670,16 +665,9 @@ def contains(self, mouseevent):
         trans = self.get_transform().inverted()
         x, y = trans.transform([mouseevent.x, mouseevent.y])
         xmin, xmax, ymin, ymax = self.get_extent()
-        if xmin > xmax:
-            xmin, xmax = xmax, xmin
-        if ymin > ymax:
-            ymin, ymax = ymax, ymin
-
-        if x is not None and y is not None:
-            inside = (xmin <= x <= xmax) and (ymin <= y <= ymax)
-        else:
-            inside = False
-
+        # This checks xmin <= x <= xmax *or* xmax <= x <= xmin.
+        inside = (x is not None and (x - xmin) * (x - xmax) <= 0
+                  and y is not None and (y - ymin) * (y - ymax) <= 0)
         return inside, {}
 
     def write_png(self, fname):