aximal chroma (colorfulness), minimal maximal luminance
(brightness, amount of gray), and a power transformations that control how
quickly/slowly chroma and/or luminance are changed through the palette.
Subsets of the parameters may not be applicable depending on the type of
palette chosen. See <code>qualitative_hcl</code> and Zeileis et al. (2009, 2019) for
a more detailed explanation of the different arguments. Stauffer et al.
(2015) provide more examples and guidance.
</p>
<p>Optionally, active palette c