Merge pull request SciTools#1969 from greglucas/v0.20-pcolormesh

Backport recent master commits to v0.20.x

.github/workflows/ci-testing.yml

@@ -24,18 +24,17 @@ jobs:
           channels: conda-forge/label/testing,conda-forge
 
       - name: Minimum packages
-        # Only run on macos for now
+        # Only run on Linux for now
         # Conda's linux packages don't grab the testing label of matplotlib causing failures due to freetype differences
-        if: matrix.python-version == '3.7' && matrix.os == 'macos-latest'
+        if: matrix.python-version == '3.7' && matrix.os == 'ubuntu-latest'
         id: minimum-packages
         run: |
           echo "PACKAGES=cython=0.28.5 matplotlib=3.1 numpy=1.18 owslib=0.17 pyproj=3.0 proj=8.0 scipy=1.2.0 shapely=1.6.4" >> $GITHUB_ENV
-          echo "CFLAGS=-stdlib=libc++" >> $GITHUB_ENV
 
       - name: Latest packages
         if: steps.minimum-packages.conclusion == 'skipped'
         run: |
-          echo "PACKAGES=cython fiona matplotlib-base numpy pyproj pykdtree scipy shapely" >> $GITHUB_ENV
+          echo "PACKAGES=cython fiona matplotlib-base numpy pyproj 'proj>=8' pykdtree scipy shapely" >> $GITHUB_ENV
 
       - name: Coverage packages
         id: coverage
@@ -51,6 +50,10 @@ jobs:
           PACKAGES="$PACKAGES flufl.lock owslib pep8 pillow pyshp pytest"
           PACKAGES="$PACKAGES pytest-xdist requests setuptools_scm"
           PACKAGES="$PACKAGES setuptools_scm_git_archive shapely"
+          # openssl 3.0 updated the legacy renegotiation default, which causes
+          # failures in NASA's WMTS server. They will need to update their
+          # server before we can use a newer openssl.
+          PACKAGES="$PACKAGES openssl<3"
           conda install $PACKAGES
           conda info -a
           conda list

lib/cartopy/mpl/geoaxes.py

@@ -1863,10 +1863,6 @@ def _wrap_quadmesh(self, collection, **kwargs):
         cross the boundary of the projection.
         """
         t = kwargs.get('transform', None)
-        if not (getattr(t, '_wrappable', False) and
-                getattr(self.projection, '_wrappable', False)):
-            # Nothing to do
-            return collection
 
         # Get the quadmesh data coordinates
         coords = collection._coordinates
@@ -1902,8 +1898,25 @@ def _wrap_quadmesh(self, collection, **kwargs):
                     np.isnan(diagonal1_lengths) |
                     (diagonal1_lengths > size_limit))
 
-        if not np.any(mask):
-            # No wrapping needed
+        # Update the data limits based on the corners of the mesh
+        # in transformed coordinates, ignoring nan values
+        with warnings.catch_warnings():
+            warnings.filterwarnings('ignore', 'All-NaN slice encountered')
+            # If we have all nans, that is OK and will be handled by the
+            # Bbox calculations later, so suppress that warning from the user
+            corners = ((np.nanmin(xs), np.nanmin(ys)),
+                       (np.nanmax(xs), np.nanmax(ys)))
+        collection._corners = mtransforms.Bbox(corners)
+        self.update_datalim(collection._corners)
+
+        # We need to keep the transform/projection check after
+        # update_datalim to make sure we are getting the proper
+        # datalims on the returned collection
+        if (not (getattr(t, '_wrappable', False) and
+                 getattr(self.projection, '_wrappable', False)) or
+                not np.any(mask)):
+            # If both projections are unwrappable
+            # or if there aren't any points to wrap
             return collection
 
         # Wrapping with gouraud shading is error-prone. We will do our best,

lib/cartopy/mpl/geocollection.py

@@ -52,3 +52,8 @@ def set_clim(self, vmin=None, vmax=None):
 
         # Update color limits for the rest of the cells.
         super().set_clim(vmin, vmax)
+
+    def get_datalim(self, transData):
+        # Return the corners that were calculated in
+        # the pcolormesh routine.
+        return self._corners

lib/cartopy/tests/mpl/test_features.py

@@ -16,7 +16,7 @@
 
 @pytest.mark.filterwarnings("ignore:Downloading")
 @pytest.mark.natural_earth
-@ImageTesting(['natural_earth'])
+@ImageTesting(['natural_earth'], tolerance=0.97)
 def test_natural_earth():
     ax = plt.axes(projection=ccrs.PlateCarree())
     ax.add_feature(cfeature.LAND)

lib/cartopy/tests/mpl/test_mpl_integration.py

@@ -19,7 +19,7 @@
 
 # This is due to a change in MPL 3.5 contour line paths changing
 # ever so slightly.
-contour_tol = 2.24
+contour_tol = 2.25
 @pytest.mark.natural_earth
 @ImageTesting(['global_contour_wrap'], style='mpl20',
               tolerance=contour_tol)
@@ -257,7 +257,7 @@ def test_cursor_values():
 
 
 @pytest.mark.natural_earth
-@ImageTesting(['natural_earth_interface'], tolerance=0.21)
+@ImageTesting(['natural_earth_interface'], tolerance=1.21)
 def test_axes_natural_earth_interface():
     rob = ccrs.Robinson()
 

lib/cartopy/tests/mpl/test_pseudo_color.py

@@ -84,3 +84,46 @@ def test_pcolormesh_arg_interpolation():
                           [2, 20],
                           [4, 20]]])
     np.testing.assert_array_almost_equal(expected, coll._coordinates)
+
+
+def test_pcolormesh_datalim():
+    # Test that wrapping the coordinates still produces proper data limits
+    x = [359, 1, 3]
+    y = [-10, 10]
+
+    xs, ys = np.meshgrid(x, y)
+    # Z with the same shape as X/Y to force the interpolation
+    z = np.zeros(xs.shape)
+
+    ax = plt.subplot(2, 1, 1, projection=ccrs.PlateCarree())
+    coll = ax.pcolormesh(xs, ys, z, shading='auto',
+                         transform=ccrs.PlateCarree())
+
+    coll_bbox = coll.get_datalim(ax.transData)
+    np.testing.assert_array_equal(coll_bbox, [[-2, -20], [4, 20]])
+
+    # Non-wrapped coordinates
+    x = [-80, 0, 80]
+    y = [-10, 10]
+
+    xs, ys = np.meshgrid(x, y)
+    ax = plt.subplot(2, 1, 1, projection=ccrs.PlateCarree())
+    coll = ax.pcolormesh(xs, ys, z, shading='auto',
+                         transform=ccrs.PlateCarree())
+
+    coll_bbox = coll.get_datalim(ax.transData)
+    np.testing.assert_array_equal(coll_bbox, [[-120, -20], [120, 20]])
+
+    # A projection that doesn't support wrapping
+    x = [-10, 0, 10]
+    y = [-10, 10]
+
+    xs, ys = np.meshgrid(x, y)
+    ax = plt.subplot(2, 1, 1, projection=ccrs.Orthographic())
+    coll = ax.pcolormesh(xs, ys, z, shading='auto',
+                         transform=ccrs.PlateCarree())
+
+    coll_bbox = coll.get_datalim(ax.transData)
+    expected = [[-1650783.327873, -2181451.330891],
+                [1650783.327873, 2181451.330891]]
+    np.testing.assert_array_almost_equal(coll_bbox, expected)