Greasy Fork is available in English.
A small cat that follows your cursor
// ==UserScript==
// @name Browser cat
// @namespace http://tampermonkey.net/
// @version 1.0
// @license MIT
// @description A small cat that follows your cursor
// @author Boofdev
// @match *://*/*
// @icon https://www.google.com/s2/favicons?sz=64&domain=githubusercontent.com
// @grant none
// ==/UserScript==
(function oneko() {
const nekoEl = document.createElement("div");
let nekoPosX = 32;
let nekoPosY = 32;
let mousePosX = 0;
let mousePosY = 0;
let frameCount = 0;
let idleTime = 0;
let idleAnimation = null;
let idleAnimationFrame = 0;
const nekoSpeed = 10;
const spriteSets = {
idle: [[-3, -3]],
alert: [[-7, -3]],
scratch: [
[-5, 0],
[-6, 0],
[-7, 0],
],
tired: [[-3, -2]],
sleeping: [
[-2, 0],
[-2, -1],
],
N: [
[-1, -2],
[-1, -3],
],
NE: [
[0, -2],
[0, -3],
],
E: [
[-3, 0],
[-3, -1],
],
SE: [
[-5, -1],
[-5, -2],
],
S: [
[-6, -3],
[-7, -2],
],
SW: [
[-5, -3],
[-6, -1],
],
W: [
[-4, -2],
[-4, -3],
],
NW: [
[-1, 0],
[-1, -1],
],
};
function create() {
nekoEl.id = "oneko";
nekoEl.style.width = "32px";
nekoEl.style.height = "32px";
nekoEl.style.position = "fixed";
nekoEl.style.pointerEvents = "none";
nekoEl.style.backgroundImage = "url('https://raw.githubusercontent.com/adryd325/oneko.js/14bab15a755d0e35cd4ae19c931d96d306f99f42/oneko.gif')";
nekoEl.style.imageRendering = "pixelated";
nekoEl.style.left = "16px";
nekoEl.style.top = "16px";
document.body.appendChild(nekoEl);
document.onmousemove = (event) => {
mousePosX = event.clientX;
mousePosY = event.clientY;
};
window.onekoInterval = setInterval(frame, 100);
}
function setSprite(name, frame) {
const sprite = spriteSets[name][frame % spriteSets[name].length];
nekoEl.style.backgroundPosition = `${sprite[0] * 32}px ${
sprite[1] * 32
}px`;
}
function resetIdleAnimation() {
idleAnimation = null;
idleAnimationFrame = 0;
}
function idle() {
idleTime += 1;
// every ~ 20 seconds
if (
idleTime > 10 &&
Math.floor(Math.random() * 200) == 0 &&
idleAnimation == null
) {
idleAnimation = ["sleeping", "scratch"][
Math.floor(Math.random() * 2)
];
}
switch (idleAnimation) {
case "sleeping":
if (idleAnimationFrame < 8) {
setSprite("tired", 0);
break;
}
setSprite("sleeping", Math.floor(idleAnimationFrame / 4));
if (idleAnimationFrame > 192) {
resetIdleAnimation();
}
break;
case "scratch":
setSprite("scratch", idleAnimationFrame);
if (idleAnimationFrame > 9) {
resetIdleAnimation();
}
break;
default:
setSprite("idle", 0);
return;
}
idleAnimationFrame += 1;
}
function frame() {
frameCount += 1;
const diffX = nekoPosX - mousePosX;
const diffY = nekoPosY - mousePosY;
const distance = Math.sqrt(diffX ** 2 + diffY ** 2);
if (distance < nekoSpeed || distance < 48) {
idle();
return;
}
idleAnimation = null;
idleAnimationFrame = 0;
if (idleTime > 1) {
setSprite("alert", 0);
// count down after being alerted before moving
idleTime = Math.min(idleTime, 7);
idleTime -= 1;
return;
}
direction = diffY / distance > 0.5 ? "N" : "";
direction += diffY / distance < -0.5 ? "S" : "";
direction += diffX / distance > 0.5 ? "W" : "";
direction += diffX / distance < -0.5 ? "E" : "";
setSprite(direction, frameCount);
nekoPosX -= (diffX / distance) * nekoSpeed;
nekoPosY -= (diffY / distance) * nekoSpeed;
nekoEl.style.left = `${nekoPosX - 16}px`;
nekoEl.style.top = `${nekoPosY - 16}px`;
}
create();
})();