Color fill error after reprojection

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
35/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Stale
Tech stack
matplotlib, python
Domain
data-visualization

Research direction

Reproduce the issue with the supplied ShapelyFeature examples, comparing PlateCarree and Mollweide projections with filled faces and edges-only rendering. Start by tracing Cartopy's ShapelyFeature and reprojection rendering path; done means the filled geometries display correctly in Mollweide without changing the correct edge rendering.

Written by the indexing model from the issue text.

Description

Hello!
I try to fill them with different colors. If I display the data as it is, in the PlateCarree projection, everything is fine.

import matplotlib.pyplot as plt
import cartopy.crs as ccrs
from cartopy.io.shapereader import Reader
from cartopy.feature import ShapelyFeature

ax = plt.axes(projection=ccrs.PlateCarree())
    
CM = ShapelyFeature(Reader('CM/10Ma_CM_v7.shp').geometries(),
                        ccrs.PlateCarree(), facecolor='skyblue', edgecolor='silver', linewidths=0.3, zorder=1)
ax.add_feature(CM)
    
CS = ShapelyFeature(Reader('CS/10Ma_CS_v7.shp').geometries(),
                        ccrs.PlateCarree(), facecolor='tan', edgecolor='black', linewidths=0.3, zorder=2)
ax.add_feature(CS)
    
ax.set_global()

ax.gridlines(zorder=4, linewidth=0.1, color='gray', alpha=0.5, linestyle='--')

plt.show()

Figure_1
Then I want to use the Mollweide projection.
ax = plt.axes(projection=ccrs.Mollweide())
Shallow water begins to occupy the entire space.
Figure_2
At the same time, if I colored only edges (facecolor='none'), edges is displayed normally.

CM = ShapelyFeature(Reader('CM/10Ma_CM_v7.shp').geometries(),
                        ccrs.PlateCarree(), facecolor='none', edgecolor='blue', linewidths=0.3, zorder=1)
ax.add_feature(CM)
    
CS = ShapelyFeature(Reader('CS/10Ma_CS_v7.shp').geometries(),
                        ccrs.PlateCarree(), facecolor='none', edgecolor='red', linewidths=0.3, zorder=2)

Figure_3
At first I thought it was due to a reprojection error. But then, when I saw that the edges were drawn correctly, I decided that it might be exactly the error of the facecolor parameter.

Windows 10, Python 3.9, Cartopy 0.20 by https://www.lfd.uci.edu/~gohlke/pythonlibs/

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