WIP: Investigation went nowhere.

This needs clean-up for production.
[ci skip]

jdaviz/app.py

@@ -1087,6 +1087,7 @@ def resize(stack_items):
             # TODO: set appropriate viewer.zoom_level
             # TODO: box-zoom to act based on overscaled canvas
             # viewer = self._viewer_by_id(args[0]['viewer'])
+            # viewer.zoom_level = 'fit'  # Did not see any difference, also tried 0.5
             pass
 
     def vue_destroy_viewer_item(self, cid):

jdaviz/configs/imviz/plugins/rotate_image/rotate_image.py

@@ -22,9 +22,10 @@ def vue_rotate_image(self, *args, **kwargs):
         except Exception:
             return
 
-        # Rotate selected viewer canvas
+        viewer = self.app._viewer_by_id(self.viewer_selected)
+
+        # Rotate selected viewer canvas. This changes zoom too.
         self.app._viewer_item_by_id(self.viewer_selected)['rotation'] = self._theta
 
-        # Update Compass
-        viewer = self.app._viewer_by_id(self.viewer_selected)
+        # Update Compass plugin.
         viewer.on_limits_change()

jdaviz/configs/imviz/plugins/viewers.py

@@ -245,6 +245,15 @@ def _get_real_xy(self, image, x, y):
 
         return x, y, coords_status
 
+    # TODO: Remove if we end up not using it.
+    # def _get_zoom_center(self, image):
+    #     """Return ``(x, y)`` of the center of zoom for a given image.
+    #     Also see :meth:`_get_zoom_limits`.
+    #     """
+    #     x_cen = (self.state.x_min + self.state.x_max) * 0.5
+    #     y_cen = (self.state.y_min + self.state.y_max) * 0.5
+    #     return self._get_real_xy(image, x_cen, y_cen)[:2]
+
     def _get_zoom_limits(self, image):
         """Return a list of ``(x, y)`` that defines four corners of
         the zoom box for a given image.