add more comments and update code based on suggestion

zhoubecky · zhoubecky · commit e8858266c713 · 2018-04-01T16:16:54.000-04:00
diff --git a/lib/matplotlib/patches.py b/lib/matplotlib/patches.py
@@ -140,7 +140,9 @@ def contains(self, mouseevent, radius=None):
         radius = self._process_radius(radius)
         codes = self.get_path().codes
         vertices = self.get_path().vertices
-        idxs, = np.nonzero(codes == 1)
+        # if the current path is concatenated by multiple sub paths.
+        # get the indexes of the starting code(MOVETO) of all sub paths
+        idxs, = np.where(codes == 1)
         # Don't split before the first MOVETO.
         idxs = idxs[1:]
         return any(
