Merge pull request matplotlib#3787 from jbbrokaw/axes3d-label-padding

Refactors axis3d.py to address issue matplotlib#3610

Author: WeatherGod

doc/users/whats_new/axis3d.rst

@@ -0,0 +1,6 @@
+Fixed labelpad in Axis3D
+```````````````````````````````````
+
+Axis3D now looks at xaxis.labelpad (from rcParams or set by
+set_xlabel('X LABEL', labelpad=30) or ax.zaxis.labelpad = 20)
+to determine the position of axis labels in 3D plots.

lib/mpl_toolkits/mplot3d/axes3d.py

@@ -1183,11 +1183,7 @@ def set_zlabel(self, zlabel, fontdict=None, labelpad=None, **kwargs):
         '''
         Set zlabel.  See doc for :meth:`set_ylabel` for description.
 
-        .. note::
-            Currently, *labelpad* does not have an effect on the labels.
         '''
-        # FIXME: With a rework of axis3d.py, the labelpad should work again
-        #        At that point, remove the above message in the docs.
         if labelpad is not None : self.zaxis.labelpad = labelpad
         return self.zaxis.set_label_text(zlabel, fontdict, **kwargs)
 

lib/mpl_toolkits/mplot3d/axis3d.py

@@ -80,12 +80,10 @@ def __init__(self, adir, v_intervalx, d_intervalx, axes, *args, **kwargs):
         # This is a temporary member variable.
         # Do not depend on this existing in future releases!
         self._axinfo = self._AXINFO[adir].copy()
-        self._axinfo.update({'label' : {'space_factor': 1.6,
-                                        'va': 'center',
+        self._axinfo.update({'label' : {'va': 'center',
                                         'ha': 'center'},
                              'tick' : {'inward_factor': 0.2,
                                        'outward_factor': 0.1},
-                             'ticklabel': {'space_factor': 0.7},
                              'axisline': {'linewidth': 0.75,
                                           'color': (0, 0, 0, 1)},
                              'grid' : {'color': (0.9, 0.9, 0.9, 1),
@@ -265,7 +263,14 @@ def draw(self, renderer):
 
         lxyz = 0.5*(edgep1 + edgep2)
 
-        labeldeltas = info['label']['space_factor'] * deltas
+        # A rough estimate; points are ambiguous since 3D plots rotate
+        ax_scale = self.axes.bbox.size / self.figure.bbox.size
+        ax_inches = np.multiply(ax_scale, self.figure.get_size_inches())
+        ax_points_estimate = sum(72. * ax_inches)
+        deltas_per_point = 48. / ax_points_estimate
+        default_offset = 21.
+        labeldeltas = (self.labelpad + default_offset) * deltas_per_point\
+            * deltas
         axmask = [True, True, True]
         axmask[index] = False
         lxyz = move_from_center(lxyz, centers, labeldeltas, axmask)
@@ -394,8 +399,10 @@ def draw(self, renderer):
                     renderer.M)
 
             # Get position of label
-            labeldeltas = [info['ticklabel']['space_factor'] * x for
-                           x in deltas]
+            default_offset = 8.  # A rough estimate
+            labeldeltas = (tick.get_pad() + default_offset) * deltas_per_point\
+                * deltas
+
             axmask = [True, True, True]
             axmask[index] = False
             pos[tickdir] = edgep1[tickdir]

lib/mpl_toolkits/tests/baseline_images/test_mplot3d/axes3d_labelpad.png

@@ -233,6 +233,30 @@ def test_quiver3d_pivot_tail():
 
     ax.quiver(x, y, z, u, v, w, length=0.1, pivot='tail')
 
+
+@image_comparison(baseline_images=['axes3d_labelpad'], extensions=['png'])
+def test_axes3d_labelpad():
+    from nose.tools import assert_equal
+    from matplotlib import rcParams
+
+    fig = plt.figure()
+    ax = Axes3D(fig)
+    # labelpad respects rcParams
+    assert_equal(ax.xaxis.labelpad, rcParams['axes.labelpad'])
+    # labelpad can be set in set_label
+    ax.set_xlabel('X LABEL', labelpad=10)
+    assert_equal(ax.xaxis.labelpad, 10)
+    ax.set_ylabel('Y LABEL')
+    ax.set_zlabel('Z LABEL')
+    # or manually
+    ax.yaxis.labelpad = 20
+    ax.zaxis.labelpad = -40
+
+    # Tick labels also respect tick.pad (also from rcParams)
+    for i, tick in enumerate(ax.yaxis.get_major_ticks()):
+        tick.set_pad(tick.get_pad() - i * 5)
+
+
 if __name__ == '__main__':
     import nose
     nose.runmodule(argv=['-s', '--with-doctest'], exit=False)