Need some nice (sharp) diverging colormaps with white in the middle

[huiwanpnnl]

We have quite a few diverging colormaps (presets) in the app, both from ParaView and from https://www.fabiocrameri.ch/colourmaps/. These tend to look muted/desaturated. It will be very useful if we can add a few diverging colormaps with high perceptual contrasts and white in the middle .

Some possible candidates are

• "seismic" in matplotlib: https://matplotlib.org/stable/users/explain/colors/colormaps.html#diverging
• "viola", "fusion", "seasons" from CMasher: https://cmasher.readthedocs.io/user/diverging.html
• "BlueWhiteOrangeRed" and "testcmap" from NCL: https://www.ncl.ucar.edu/Document/Graphics/ColorTables/White-in-the-middle_cat.shtml

Thanks!