Use arrow keys or ESDF to move.
// ==UserScript==
// @name Agar Movement Keys
// @description Use arrow keys or ESDF to move.
// @version 0.2
// @match http://agar.io/
// @grant none
// @namespace https://greasyfork.org/users/12022
// ==/UserScript==
// Get canvas and create an object with (fake) mouse position properties.
var canvas = document.getElementById("canvas");
var endPoint = {clientX: innerWidth / 2, clientY: innerHeight / 2};
// Closure:
var handleKeys = (function() {
// KeyCodes and an object for storing key states.
var keys = [37, 38, 39, 40, 83, 69, 70, 68];
var key = {left: "keyup", up: "keyup", right: "keyup", down: "keyup"};
// Stop movement and reset center when window loses focus or is resized.
["blur", "resize"].forEach(function(listener) {
window.addEventListener(listener, function() {
key.left = key.up = key.right = key.down = "keyup";
endPoint = {clientX: innerWidth / 2, clientY: innerHeight / 2};
canvas.onmousedown(endPoint);
}, false);
});
// The actual handleKeys function.
return function(event, keyState) {
// Stop if keydown is repeating.
if (event.repeat && keyState === "keydown") return;
// Iterate through keycodes.
for (var i = 0; i < keys.length; i++) {
// If keycode doesn't match, skip it.
if (event.which !== keys[i]) continue;
// Get axis based on key index, odd = y, even = x. Store directions (axis.dir) to be evaluated next.
var axis = (i % 2) ? {dir: ["up", "down"], value: "clientY"} : {dir: ["left", "right"], value: "clientX"};
// Get direction based on index and axis. If divisible by 4, direction must be up or left (depending on the axis).
var direction = ((i % 4) === 0 || ((i - 1) % 4) === 0) ? axis.dir[0] : axis.dir[1];
// If key state is already set, return.
if (key[direction] === keyState) return;
// Else, set it.
key[direction] = keyState;
// Positive or negative value based on key state.
var point = (keyState === "keydown") ? 1000 : -1000;
// Invert value if direction is left or up.
point = (direction === "left" || direction === "up") ? -point : point;
// Add point to fake mouse position property.
endPoint[axis.value] += point;
// Return true to send the movement.
return true;
}
};
})();
// Send all key events to handleKeys.
["keydown", "keyup"].forEach(function(keyState) {
window.addEventListener(keyState, function(event) {
// Send movement if handleKeys returns true.
if (handleKeys(event, keyState)) canvas.onmousedown(endPoint);
}, false);
});
// Stop the default mouse move behavior.
(function nullMouseMove(startTime) {
if (Date.now() - startTime > 5000) return;
if (!canvas.onmousemove) return setTimeout(nullMouseMove, 0, startTime);
canvas.onmousemove = null;
})(Date.now());