Gridliner inline label projection hard-coded for WGS84 #1902
Description
Description
Calling cartopy.crs.Projection.gridlines() with a CRS using a non-WGS84 Globe and with x_inline=True raises an exception during drawing, apparently due to gridliner.py:800: when either axis is specified as inline, the transform used comes from a newly-instantiated PlateCarree projection with a default Globe (i.e., a WGS84 globe).
The raised exception message is ProjError: Error creating Transformer from CRS.: (Internal Proj Error: proj_create_operations: Source and target ellipsoid do not belong to the same celestial body).
Code to reproduce
import matplotlib.pyplot as plt
import cartopy.crs as ccrs
globe = ccrs.Globe(semimajor_axis=1, semiminor_axis=1, ellipse=None)
projection = data_ccrs = ccrs.PlateCarree(globe=globe)
plt.figure()
ax = plt.subplot(111, projection=projection)
ax.set_global()
ax.gridlines(crs=data_ccrs, draw_labels=['x'], x_inline=True)
plt.show()
Traceback
Traceback (most recent call last):
File "/usr/lib64/python3.10/site-packages/matplotlib/backends/backend_gtk3cairo.py", line 31, in on_draw_event
self.figure.draw(self._renderer)
File "/usr/lib64/python3.10/site-packages/matplotlib/artist.py", line 72, in draw_wrapper
result = draw(artist, renderer, *args, **kwargs)
File "/usr/lib64/python3.10/site-packages/matplotlib/artist.py", line 49, in draw_wrapper
return draw(artist, renderer)
File "/usr/lib64/python3.10/site-packages/matplotlib/figure.py", line 2799, in draw
mimage._draw_list_compositing_images(
File "/usr/lib64/python3.10/site-packages/matplotlib/image.py", line 132, in _draw_list_compositing_images
a.draw(renderer)
File "/usr/lib64/python3.10/site-packages/matplotlib/artist.py", line 49, in draw_wrapper
return draw(artist, renderer)
File "/usr/lib64/python3.10/site-packages/cartopy/mpl/geoaxes.py", line 543, in draw
self._draw_preprocess(renderer)
File "/usr/lib64/python3.10/site-packages/cartopy/mpl/geoaxes.py", line 517, in _draw_preprocess
gl._draw_gridliner(renderer=renderer)
File "/usr/lib64/python3.10/site-packages/cartopy/mpl/gridliner.py", line 948, in _draw_gridliner
this_path = update_artist(artist, renderer)
File "/usr/lib64/python3.10/site-packages/cartopy/mpl/gridliner.py", line 775, in update_artist
artist.update_bbox_position_size(renderer)
File "/usr/lib64/python3.10/site-packages/matplotlib/text.py", line 506, in update_bbox_position_size
posx, posy = self.get_transform().transform((posx, posy))
File "/usr/lib64/python3.10/site-packages/matplotlib/transforms.py", line 1463, in transform
res = self.transform_affine(self.transform_non_affine(values))
File "/usr/lib64/python3.10/site-packages/matplotlib/transforms.py", line 2386, in transform_non_affine
return self._a.transform_non_affine(points)
File "/usr/lib64/python3.10/site-packages/cartopy/mpl/geoaxes.py", line 134, in transform_non_affine
return prj.transform_points(self.source_projection,
File "/usr/lib64/python3.10/site-packages/cartopy/crs.py", line 401, in transform_points
_safe_pj_transform(src_crs, self, x, y, z, trap=trap)
File "/usr/lib64/python3.10/site-packages/cartopy/crs.py", line 43, in _safe_pj_transform
transformer = Transformer.from_crs(src_crs, tgt_crs, always_xy=True)
File "/usr/lib64/python3.10/site-packages/pyproj/transformer.py", line 534, in from_crs
return Transformer(
File "/usr/lib64/python3.10/site-packages/pyproj/transformer.py", line 310, in __init__
self._local.transformer = transformer_maker()
File "/usr/lib64/python3.10/site-packages/pyproj/transformer.py", line 97, in __call__
return _Transformer.from_crs(
File "pyproj/_transformer.pyx", line 643, in pyproj._transformer._Transformer.from_crs
pyproj.exceptions.ProjError: Error creating Transformer from CRS.: (Internal Proj Error: proj_create_operations: Source and target ellipsoid do not belong to the same celestial body)
Full environment definition
Operating system
Fedora 35
Cartopy version
v0.20.0, but appears to be an issue on master.