matplotlib · efiring · May 31, 2012 · May 29, 2012
diff --git a/CHANGELOG b/CHANGELOG
@@ -1,3 +1,8 @@
+2012-05-29 pcolormesh now obeys the passed in "edgecolor" kwarg.
+	   To support this, the "shading" argument to pcolormesh now only
+	   takes "flat" or "gouraud".  To achieve the old "faceted" behavior,
+	   pass "edgecolors='k'". - MGD
+
 2012-05-22 Added radius kwarg to pie charts. - HH
 
 2012-05-22 Collections now have a setting "offset_position" to select whether

diff --git a/lib/matplotlib/axes.py b/lib/matplotlib/axes.py
@@ -7164,14 +7164,10 @@ def pcolormesh(self, *args, **kwargs):
             and max of the color array *C* is used.  If you pass a
             *norm* instance, *vmin* and *vmax* will be ignored.
 
-          *shading*: [ 'flat' | 'faceted' | 'gouraud' ]
-            If 'faceted', a black grid is drawn around each rectangle; if
-            'flat', edges are not drawn. Default is 'flat', contrary to
-            MATLAB.
-
-            This kwarg is deprecated; please use 'edgecolors' instead:
-              * shading='flat' -- edgecolors='None'
-              * shading='faceted  -- edgecolors='k'
+          *shading*: [ 'flat' | 'gouraud' ]
+            'flat' indicates a solid color for each quad.  When
+            'gouraud', each quad will be Gouraud shaded.  When gouraud
+            shading, edgecolors is ignored.
 
           *edgecolors*: [ *None* | ``'None'`` | color | color sequence]
             If *None*, the rc setting is used by default.
@@ -7205,7 +7201,6 @@ def pcolormesh(self, *args, **kwargs):
         vmin = kwargs.pop('vmin', None)
         vmax = kwargs.pop('vmax', None)
         shading = kwargs.pop('shading', 'flat').lower()
-        edgecolors = kwargs.pop('edgecolors', 'None')
         antialiased = kwargs.pop('antialiased', False)
 
         X, Y, C = self._pcolorargs('pcolormesh', *args)
@@ -7224,13 +7219,8 @@ def pcolormesh(self, *args, **kwargs):
         coords[:, 0] = X
         coords[:, 1] = Y
 
-        if shading == 'faceted' or edgecolors != 'None':
-            showedges = 1
-        else:
-            showedges = 0
-
         collection = mcoll.QuadMesh(
-            Nx - 1, Ny - 1, coords, showedges,
+            Nx - 1, Ny - 1, coords,
             antialiased=antialiased, shading=shading, **kwargs)
         collection.set_alpha(alpha)
         collection.set_array(C)

diff --git a/lib/matplotlib/backend_bases.py b/lib/matplotlib/backend_bases.py
@@ -224,7 +224,7 @@ def draw_path_collection(self, gc, master_transform, paths, all_transforms,
 
     def draw_quad_mesh(self, gc, master_transform, meshWidth, meshHeight,
                        coordinates, offsets, offsetTrans, facecolors,
-                       antialiased, showedges):
+                       antialiased, edgecolors):
         """
         This provides a fallback implementation of
         :meth:`draw_quad_mesh` that generates paths and then calls
@@ -234,12 +234,9 @@ def draw_quad_mesh(self, gc, master_transform, meshWidth, meshHeight,
         paths = QuadMesh.convert_mesh_to_paths(
             meshWidth, meshHeight, coordinates)
 
-        if showedges:
-            edgecolors = np.array([[0.0, 0.0, 0.0, 1.0]], np.float_)
-            linewidths = np.array([gc.get_linewidth()], np.float_)
-        else:
+        if edgecolors is None:
             edgecolors = facecolors
-            linewidths = np.array([gc.get_linewidth()], np.float_)
+        linewidths = np.array([gc.get_linewidth()], np.float_)
 
         return self.draw_path_collection(
             gc, master_transform, paths, [], offsets, offsetTrans, facecolors,

diff --git a/lib/matplotlib/backends/backend_template.py b/lib/matplotlib/backends/backend_template.py
@@ -98,7 +98,7 @@ def draw_path(self, gc, path, transform, rgbFace=None):
     # performance will probably want to implement it
 #     def draw_quad_mesh(self, gc, master_transform, meshWidth, meshHeight,
 #                        coordinates, offsets, offsetTrans, facecolors,
-#                        antialiased, showedges):
+#                        antialiased, edgecolors):
 #         pass
 
     def draw_image(self, gc, x, y, im):
@@ -253,4 +253,3 @@ class FigureManagerTemplate(FigureManagerBase):
 
 
 FigureManager = FigureManagerTemplate
-
diff --git a/lib/matplotlib/collections.py b/lib/matplotlib/collections.py
@@ -1301,15 +1301,14 @@ class QuadMesh(Collection):
     at (0, 1), then at (0, 2) .. (0, meshWidth), (1, 0), (1, 1), and
     so on.
 
-    *shading* may be 'flat', 'faceted' or 'gouraud'
+    *shading* may be 'flat', or 'gouraud'
     """
-    def __init__(self, meshWidth, meshHeight, coordinates, showedges,
+    def __init__(self, meshWidth, meshHeight, coordinates,
                  antialiased=True, shading='flat', **kwargs):
         Collection.__init__(self, **kwargs)
         self._meshWidth = meshWidth
         self._meshHeight = meshHeight
         self._coordinates = coordinates
-        self._showedges = showedges
         self._antialiased = antialiased
         self._shading = shading
 
@@ -1449,7 +1448,7 @@ def draw(self, renderer):
             renderer.draw_quad_mesh(
                 gc, transform.frozen(), self._meshWidth, self._meshHeight,
                 coordinates, offsets, transOffset, self.get_facecolor(),
-                self._antialiased, self._showedges)
+                self._antialiased, self.get_edgecolors())
         gc.restore()
         renderer.close_group(self.__class__.__name__)
 

diff --git a/lib/matplotlib/tests/baseline_images/test_axes/pcolormesh.pdf b/lib/matplotlib/tests/baseline_images/test_axes/pcolormesh.pdf
diff --git a/lib/matplotlib/tests/baseline_images/test_axes/pcolormesh.png b/lib/matplotlib/tests/baseline_images/test_axes/pcolormesh.png