Light or Dark

library to determine if the color parameter is a 'light' or a 'dark' color

Цей скрипт не слід встановлювати безпосередньо. Це - бібліотека для інших скриптів для включення в мета директиву // @require https://update.greasyfork.org/scripts/491888/1355841/Light%20or%20Dark.js

You will need to install an extension such as Tampermonkey, Greasemonkey or Violentmonkey to install this script.

You will need to install an extension such as Tampermonkey to install this script.

You will need to install an extension such as Tampermonkey or Violentmonkey to install this script.

You will need to install an extension such as Tampermonkey or Userscripts to install this script.

You will need to install an extension such as Tampermonkey to install this script.

You will need to install a user script manager extension to install this script.

(У мене вже є менеджер скриптів, дайте мені встановити його!)

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install a user style manager extension to install this style.

You will need to install a user style manager extension to install this style.

You will need to install a user style manager extension to install this style.

(I already have a user style manager, let me install it!)

// ==UserScript==
// @name         Light or Dark
// @namespace    https://greasyfork.org/en/users/906106-escctrl
// @description  library to determine if the color parameter is a 'light' or a 'dark' color
// @author       escctrl
// @version      1.0
// @grant        none
// @license      MIT
// ==/UserScript==

// helper function to determine whether a color (the background in use) is light or dark
// https://awik.io/determine-color-bright-dark-using-javascript/
function lightOrDark(color) {
    var r, g, b, hsp;
    if (color.match(/^rgb/)) { color = color.match(/^rgba?\((\d+),\s*(\d+),\s*(\d+)(?:,\s*(\d+(?:\.\d+)?))?\)$/);
        r = color[1]; g = color[2]; b = color[3]; }
    else { color = +("0x" + color.slice(1).replace(color.length < 5 && /./g, '$&$&'));
        r = color >> 16; g = color >> 8 & 255; b = color & 255; }
    hsp = Math.sqrt( 0.299 * (r * r) + 0.587 * (g * g) + 0.114 * (b * b) );
    if (hsp>127.5) { return 'light'; } else { return 'dark'; }
}