implement xtick rotation mode

kyracho · kyracho · commit ee92312dbe4c · 2024-10-11T11:46:29.000Z
diff --git a/lib/matplotlib/axis.py b/lib/matplotlib/axis.py
@@ -346,6 +346,11 @@ def _apply_params(self, **kwargs):
                    if k in _gridline_param_names}
         self.gridline.set(**grid_kw)
 
+        if 'rotation_mode' in kwargs:
+            rotation_mode = kwargs.pop('rotation_mode')
+            self.label1.set_rotation_mode(rotation_mode)
+            self.label2.set_rotation_mode(rotation_mode)
+
     def update_position(self, loc):
         """Set the location of tick in data coords with scalar *loc*."""
         raise NotImplementedError('Derived must override')
@@ -1072,7 +1077,7 @@ def _translate_tick_params(kw, reverse=False):
             'tick1On', 'tick2On', 'label1On', 'label2On',
             'length', 'direction', 'left', 'bottom', 'right', 'top',
             'labelleft', 'labelbottom', 'labelright', 'labeltop',
-            'labelrotation',
+            'labelrotation', 'rotation_mode',
             *_gridline_param_names]
 
         keymap = {
diff --git a/lib/matplotlib/text.py b/lib/matplotlib/text.py
@@ -310,7 +310,7 @@ def set_rotation_mode(self, m):
         if m is None:
             m = "default"
         else:
-            _api.check_in_list(("anchor", "default"), rotation_mode=m)
+            _api.check_in_list(("anchor", "default", "xtick"), rotation_mode=m)
         self._rotation_mode = m
         self.stale = True
 
@@ -453,7 +453,24 @@ def _get_layout(self, renderer):
         valign = self._verticalalignment
 
         rotation_mode = self.get_rotation_mode()
+
+        def ha_for_angle(angle):
+            """
+            Determines horizontal alignment ('ha') based on the angle of rotation.
+            """
+            if (angle < 20 or 80 <= angle < 110 or 340 <= angle <= 360 or
+                    160 <= angle < 200 or 240 <= angle < 300):
+                return 'center'
+            elif 20 <= angle < 80 or 200 <= angle < 240:
+                return 'right'
+            elif 110 <= angle < 160 or 300 <= angle < 340:
+                return 'left'
+
         if rotation_mode != "anchor":
+            if rotation_mode == 'xtick':
+                # Compute horizontal alignment based on the angle
+                angle = self.get_rotation()
+                halign = ha_for_angle(angle)    # Use Tim's function
             # compute the text location in display coords and the offsets
             # necessary to align the bbox with that location
             if halign == 'center':
