[docs] Document and exposes colorManipulator helpers

• I have searched the issues of this repository and believe that this is not a duplicate.

In recent beta’s it looks like a lot of nice simplifications have been made to the theme palette approach. However, there is one thing which is unclear to me. In my old code, I was able to have logic like this:

theme.palette.primary[200]

The closest thing I seem to have now is to use colorManipulator.lighten and darken, passing in a relative value as the “coefficient” e.g.

lighten(theme.palette.primary.main, 0.25)

Is this the “right” approach to use now? If so, the docs should probably describe the best way to use these methods, and typical values of the coefficient value to achieve various shades in the source palette. For example, is it true to say that, assuming primary.main is the equivalent of primary[500] before, then primary[200] would now be achieved via a coefficient of 0.4, since 200/500=0.4?

[oliviertassinari]

@rocketraman There are no official alternatives to the theme.palette.primary[200] style. You can always use the color[200] style when using an official Material Design color.

Right now, the colorManipulator helper functions are considered a private API, they aren’t exposed in the index nor documented. Should we make it a public API? I don’t know. Color manipulation isn’t our core mission, maybe there is better open source solution out there. But at the same time, ours are stable and haven’t changed in a long time. So why not.

You can find some shared pain points with #10499.

[mbrookes]

@oliviertassinari Did you mean #13039, or did you mean to close #13039 for #10789 (this issue)?