Merge pull request matplotlib#4477 from has2k1/tight_layout-for-offsetboxes

ENH: OffsetBoxes now considered by tight_layout

Author: tacaswell

doc/users/whats_new/offsetbox.rst

@@ -9,3 +9,12 @@ text is always within the bounds, for this nothing has changed.
 However, `DrawingArea` acts as a parent for zero or more `Artists` that
 draw on it and may do so beyond the bounds. Now child `Artists` can be
 clipped to the bounds of the `DrawingArea`.
+
+
+OffsetBoxes now considered by tight_layout
+``````````````````````````````````````````
+
+When :method:`pyplot.tight_layout()` or :method:`Figure.tight_layout()`
+or :method:`GridSpec.tight_layout()` is called, `OffsetBoxes` that are
+anchored outside the axes will not get chopped out. The `OffsetBoxes` will
+also not get overlapped by other axes in case of multiple subplots.

lib/matplotlib/axes/_base.py

@@ -29,6 +29,7 @@
 import matplotlib.font_manager as font_manager
 import matplotlib.text as mtext
 import matplotlib.image as mimage
+from matplotlib.offsetbox import OffsetBox
 from matplotlib.artist import allow_rasterization
 from matplotlib.cbook import iterable
 
@@ -3306,6 +3307,10 @@ def get_tightbbox(self, renderer, call_axes_locator=True):
         if bb_yaxis:
             bb.append(bb_yaxis)
 
+        for child in self.get_children():
+            if isinstance(child, OffsetBox) and child.get_visible():
+                bb.append(child.get_window_extent(renderer))
+
         _bbox = mtransforms.Bbox.union(
             [b for b in bb if b.width != 0 or b.height != 0])