new shading default can mess up plots #1638
Description
Description
The new shading default
cartopy/lib/cartopy/mpl/geoaxes.py
Line 1669 in 08db54f
can lead to artifacts in the plot which do not happen with
shading="flat". This happens for coordinates that cross the zero line. As far as I can see matplotlib plans to entirely remove this option?
Code to reproduce
I was too lazy to create an example without xarray as dependency - let me know if you need one:
Artifacts:
import cartopy.crs as ccrs
import xarray as xr
rasm = xr.tutorial.load_dataset("rasm")
# choose a projection
proj = ccrs.NorthPolarStereo()
ax = plt.subplot(111, projection=proj)
ax.set_global()
rasm.isel(time=1).Tair.plot.pcolormesh(
ax=ax, x="xc", y="yc", transform=ccrs.PlateCarree()
)
ax.set_extent([-180, 180, 43, 90], ccrs.PlateCarree())
ax.coastlines();No artifacts:
f = plt.fugure()
ax = plt.subplot(111, projection=proj)
ax.set_global()
rasm.isel(time=1).Tair.plot.pcolormesh(
ax=ax, x="xc", y="yc", transform=ccrs.PlateCarree(), shading="flat"
)
ax.set_extent([-180, 180, 43, 90], ccrs.PlateCarree())
ax.coastlines();Full environment definition
Operating system
linux
Cartopy version
0.18.0
conda list
# packages in environment at /home/mathause/conda/envs/xarray_dev:
#
# Name Version Build Channel
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pip list