Document colorManipulator methods

[danielo515]

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

Summary 💡

Today I discovered that materialui provides a set of color manipulation helpers under @material-ui/core/styles/colorManipulator.
I searched through the docs and I didn't saw any reference to any of the methods contained there, albeit they areextremelyy useful.

Motivation 🔦

I am pretty sure that there is a lot of people which are using material-ui looking for small libraries for this kind of simple tasks and having this will be very handy.

[bartlomiejzuber]

As far as I know, mui says that everything below 2nd level deep is consider as private and you shouldn't use it. Instead I would recommend to use some alternative like:
https://www.npmjs.com/package/color or https://github.com/gka/chroma.js/

ex.

import color from "color";

const backgroundColor = color("rgba(247,248,249,0.5)");
const useStyles = makeStyles((theme: Theme) => ({
  container: {
    backgroundColor: backgroundColor.string()
  },
  dragging: {
    backgroundColor: backgroundColor.darken(0.05).string()
  },
  over: {
    backgroundColor: backgroundColor.darken(0.1).string()
  }
}));

[danielo515]

That is the thing. Why should I add 16 extra KB to an already big bundle for something that is built into the library that I'm already using?

[mbrookes]

Duplicate of #13039?