Light or Dark

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

สคริปต์นี้ไม่ควรถูกติดตั้งโดยตรง มันเป็นคลังสำหรับสคริปต์อื่น ๆ เพื่อบรรจุด้วยคำสั่งเมทา // @require https://update.greasyfork.org/scripts/491888/1355841/Light%20or%20Dark.js

คุณจะต้องติดตั้งส่วนขยาย เช่น Tampermonkey, Greasemonkey หรือ Violentmonkey เพื่อติดตั้งสคริปต์นี้

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

คุณจะต้องติดตั้งส่วนขยาย เช่น Tampermonkey หรือ Violentmonkey เพื่อติดตั้งสคริปต์นี้

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.

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

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'; }
}