Khrôma
A collection of functions for manipulating CSS colors, inspired by SASS.
Features
- Small: the entire library weighs ~5kb (min + gzip) and has no dependencies.
- Fast: in our benchmark suite functions are executed at ~0.0025ms per call on a mid-2014 MBP.
- Flexible: All valid CSS colors are supported.
- SASS-like: if you're familiar with SASS you should feel right at home.
Install
npm install --save khromaUsage
import {red, isDark, darken, change} from 'khroma';
red ( '#ffffff' ); // => 255
isDark ( 'white' ); // => false
darken ( 'hsl(0, 5%, 100%)', 50 ); // => 'hsl(0, 5%, 50%)'
change ( 'rgb(255, 255, 255)', { a: 0.5 } ); // => 'rgba(255, 255, 255, 0.5)'Functions
These are all the provided functions, for each of them below you can find a short description, its interface and examples.
| Create | Convert | Get channel | Get more | Edit channel | Edit more |
|---|---|---|---|---|---|
| hex | toKeyword | channel | contrast | saturate | adjust |
| rgb | toHex | red | luminance | desaturate | change |
| rgba | toRgba | green | isDark | lighten | invert |
| hsl | toHsla | blue | isLight | darken | mix |
| hsla | hue | isValid | opacify | scale | |
| saturation | fadeIn | ||||
| lightness | transparentize | ||||
| alpha | fadeOut | ||||
| opacity | rgba (alt) | ||||
| complement | |||||
| grayscale |
Create
These functions create a new color given the provided channels.
hex
Alias for rgba.
rgb
Alias for rgba.
rgba
Creates a new color given its rgba channels, the alpha channel is optional.
function rgba ( r: string, g: number, b: number, a: number = 1 ): string;rgba ( 255, 204, 0 ); // => '#ffcc00'
rgba ( 255, 204, 0, 0.5 ); // => 'rgba(255, 204, 0, 0.5)'hsl
Alias for hsla.
hsla
Creates a new color given its hsla channels, the alpha channel is optional.
function hsla ( h: number, s: number, l: number, a: number = 1 ): string;hsla ( 0, 50, 100 ); // => 'hsl(0, 50%, 100%)'
hsla ( 10, 50, 100, 0.5 ); // => 'hsla(10, 50%, 100%, 0.5)'Convert
These functions convert supported colors to a specific format.
toKeyword
Convert a color to the keyword format, when possible.
function toKeyword ( color: string ): string | undefined;toKeyword ( '#ff0000' ); // => 'red'
toKeyword ( '#ffcc00' ); // => undefinedtoHex
Convert a color to the HEX format.
function toHex ( color: string ): string;toHex ( 'red' ); // => '#ff0000'
toHex ( '#ff0000' ); // => '#ff0000'toRgba
Convert a color to the RGBA format.
function toRgba ( color: string ): string;toRgba ( 'red' ); // => 'rgb(255, 0, 0)'
toRgba ( '#ff0000' ); // => 'rgb(255, 0, 0)'
toRgba ( '#00000088' ); // => 'rgba(0, 0, 0, 0.5333333333)'toHsla
Convert a color to the HSLA format.
function toHsla ( color: string ): string;toHsla ( 'red' ); // => 'hsl(0, 100%, 50%)'
toHsla ( '#ff0000' ); // => 'hsl(0, 100%, 50%)'
toHsla ( 'rgb(255, 0, 0)' ); // => 'hsl(0, 100%, 50%)'Get channel
These functions get a single channel from the provided color.
channel
Gets any single channel of the color.
function channel ( color: string, channel: 'r' | 'g' | 'b' | 'h' | 's' | 'l' | 'a' ): number;channel ( '#ffcc00', 'r' ); // => 255
channel ( '#ffcc00', 'h' ); // => 48
channel ( '#ffcc00', 'a' ); // => 1red
Gets the red channel of the color.
function red ( color: string ): number;red ( '#ffcc00' ); // => 255green
Gets the green channel of the color.
function green ( color: string ): number;green ( '#ffcc00' ); // => 204blue
Gets the blue channel of the color.
function blue ( color: string ): number;blue ( '#ffcc00' ); // => 0hue
Gets the hue channel of the color.
function hue ( color: string ): number;hue ( 'hsl(0, 50%, 100%)' ); // => 0saturation
Gets the saturation channel of the color.
function saturation ( color: string ): number;saturation ( 'hsl(0, 50%, 100%)' ); // => 50lightness
Gets the lightness channel of the color.
function lightness ( color: string ): number;lightness ( 'hsl(0, 50%, 100%)' ); // => 100alpha
Gets the alpha channel of the color.
function alpha ( color: string ): number;alpha ( '#ffcc00' ); // => 1
alpha ( 'rgba(255, 205, 0, 0.5)' ); // => 0.5opacity
Alias for alpha.
Get more
These functions get some other information from the provided color.
contrast
Gets the contrast in luminance between two colors.
Contrast values go between 1 and 10. 1 means same color, >= 4 means decent contrast, >= 7 means great contrast, 10 means great contrast.
function contrast ( color1: string, color2: string ): number;contrast ( '#000000', '#000000' ); // => 1
contrast ( '#000000', '#ffffff' ); // => 10
contrast ( '#888888', '#ffffff' ); // => 4.0617165366luminance
Gets the relative luminance of the color.
function luminance ( color: string ): number;luminance ( 'black' ); // => 0
luminance ( 'white' ); // => 1
luminance ( '#ffcc00' ); // => 0.6444573127isDark
Checks if the provided color is a dark color.
function isDark ( color: string ): number;isDark ( 'black' ); // => true
isDark ( 'white' ); // => false
isDark ( '#ffcc00' ); // => falseisLight
Checks if the provided color is a light color.
function isLight ( color: string ): number;isLight ( 'black' ); // => false
isLight ( 'white' ); // => true
isLight ( '#ffcc00' ); // => trueisValid
Checks if the provided color is a valid color.
function isLight ( color: string ): boolean;isValid ( 'black' ); // => true
isValid ( '#ffcc00' ); // => true
isValid ( '#wtf' ); // => falseEdit channel
These functions change a single channel of the provided color.
saturate
Increases the saturation channel of the color.
function saturate ( color: string, amount: number ): string;saturate ( 'hsl(0, 50%, 50%)', 25 ); // => 'hsl(0, 75%, 50%)'desaturate
Decreases the saturation channel of the color.
function desaturate ( color: string, amount: number ): string;desaturate ( 'hsl(0, 50%, 50%)', 25 ); // => 'hsl(0, 25%, 50%)'lighten
Increases the lightness channel of the color.
function lighten ( color: string, amount: number ): string;lighten ( 'hsl(0, 50%, 50%)', 25 ); // => 'hsl(0, 50%, 75%)'darken
Decreases the lightness channel of the color.
function darken ( color: string, amount: number ): string;darken ( 'hsl(0, 50%, 50%)', 25 ); // => 'hsl(0, 50%, 25%)'opacify
Increases the opacity channel of the color.
function opacify ( color: string, amount: number ): string;opacify ( 'rgba(255, 204, 0, 0.5)', 0.25 ); // => 'rgba(255, 204, 0, 0.75)'fadeIn
Alias for opacify.
transparentize
Decreases the opacity channel of the color.
function transparentize ( color: string, amount: number ): string;transparentize ( 'rgba(255, 204, 0, 0.5)', 0.25 ); // => 'rgba(255, 204, 0, 0.25)'fadeOut
Alias for transparentize.
rgba (alt)
Sets a new value for the opacity channel.
function rgba ( color: string, amount: number ): string;rgba ( 'rgba(255, 204, 0, 0.5)', 0.1 ); // => 'rgba(255, 204, 0, 0.1)'complement
Gets the complement of the color, rotating its hue channel by 180 degrees.
function complement ( color: string ): string;complement ( '#ffcc00' ); // => 'hsl(228, 100%, 50%)'grayscale
Gets the grayscale version of the color, setting its saturation to 0.
function grayscale ( color: string ): string;grayscale ( '#ffcc00' ); // => 'hsl(48, 0%, 50%)'Edit more
These functions can/will change more than a single channel at once of the provided color.
adjust
Increases or decreases the value of any channel of the color.
function adjust ( color: string, channels: Record<'r' | 'g' | 'b' | 'h' | 's' | 'l' | 'a', number> ): string;adjust ( '#ffcc00', { r: -10, g: 200 } ); // => '#f5ff00'
adjust ( '#ffcc00', { a: -0.5 } ); // => 'rgba(255, 204, 0, 0.5)'
adjust ( '#ffcc00', { h: 50, l: -30 } ); // => 'hsl(98, 100%, 20%)'change
Sets a new value for any channel of the color.
function change ( color: string, channels: Record<'r' | 'g' | 'b' | 'h' | 's' | 'l' | 'a', number> ): string;change ( '#ffcc00', { r: 10, g: 200 } ); // => '#0ac800'
change ( '#ffcc00', { a: 0.5 } ); // => 'rgba(255, 204, 0, 0.5)'
change ( '#ffcc00', { h: 50, l: 30 } ); // => 'hsl(50, 100%, 30%)'invert
Gets the inverse of the color.
function invert ( color: string, weight: number = 100 ): string;invert ( '#ffcc00' ); // => '#0033ff'
invert ( '#ffcc00', 50 ); // => '#808080'mix
Mixes two colors together.
function mix ( color1: string, color2: string, weight: number = 50 ): string;mix ( 'red', 'blue' ); // => '#800080'
mix ( 'red', 'blue', 15 ); // => '#2600d9'scale
Scales any channel of the color.
function scale ( color: string, channels: Record<'r' | 'g' | 'b' | 'h' | 's' | 'l' | 'a', number> ): string;scale ( '#ffcc00', { r: -50, b: 10 } ); // => '#80cc1a'License
MIT © Fabio Spampinato, Andrew Maney