yiq/README.md

Returns light when a color is dark and dark when a color is light (and a little more).

# YIQ

Returns light when a color is dark and dark when a color is light. 🎨

[![CI](https://github.com/lffg/yiq/workflows/CI/badge.svg)](https://github.com/lffg/errou/actions)
[![NPM](https://img.shields.io/npm/v/yiq.svg?logo=npm)](https://npmjs.org/package/yiq)
![Uses TypeScript](https://img.shields.io/badge/Uses-Typescript-294E80.svg)

## Installing

```shell
yarn add yiq

# If you're using NPM:
# npm install yiq --save
```

## Basic Usage

Just call the `yiq` function after importing it:

```typescript
import { yiq } from 'yiq';

console.log(yiq('#fff')); // #000
console.log(yiq('#000')); // #fff
```

## API

### `yiq`

`yiq` — Returns a light color when a color is dark and a dark color when a color is light.

#### Description

```typescript
function yiq(
  colorHex: string,
  options?: {
    colors?: {
      light: string;
      dark: string;
    };
    threshold?: number;
  }
): string;
```

The second argument (options) can be used to define the colors that the function will return:

```typescript
yiq('#fff', {
  colors: {
    light: '#f0f0f0',
    dark: '#333'
  }
}); // #333
```

It can also be used to define the threshold YIQ value at which the function switches between light and dark:

```typescript
yiq('#36d386', { threshold: 156 }); // #fff
```

The default options are:

- `options.colors.light`: `#fff`;
- `options.colors.dark`: `#000`;
- `options.threshold`: `128`.

## Authors and License

[lffg](https://github.com/lffg) and [contributors](https://github.com/lffg/yiq/graphs/contributors).

MIT License, see the included [MIT](https://github.com/lffg/yiq/blob/master/LICENSE) file.