Script to add viridis and other colorblind-accessible (and perceptually uniform) palettes to PyMOL and viridis to color (C) menus. The default palette for spectrum is set to turbo.

All the new palettes (viridis, magma, inferno, plasma, cividis, turbo) can be used in pymol wherever builtin palettes can be specified, e.g. instead of specifying ... spectrum palette="blue_green" ... , specify ... spectrum="viridis" ....

Just run viridispalettes.py and you are off!

New palettes are added to the dictionary pymol.viewing.palette_colors_dict with their common name as key and palette specified as space-delimited string of hex colors (prefix 0x not #) as value.

spectrum uses palette=rainbow by default and is monkey patched to use palette=turbo by default instead.

New menus/menu-options are created where ever spectrum options exist by simply specifying the palette='viridis' to the spectrum invocation. Text is colorized for viridis options by using the \\RGB specification.

The new colormaps are added via their 256-hex colors from bokeh.palettes (not via named colors) to stay as true as possible to the original colormap specifications.

Interpolation (when done) is handled by spectrumany. In the current release (v2.3), this is done linearly in RGB space. In future versions, interpolation can be done in a more perceptual space (Issue in Pymol repo/PR by @speleo3). Since the colormaps here are specified in terms of 256 hex colors, interpolation in RGB will be just fine.