Implementing a pause and resume mechanism for javascript loop execution

Question

I\'m trying to provide a pause and resume functionality to a loop with recursive calls. I\'m using \"setTimeout\" and \"clearTimeout\" functions for this...

When a u

Answer 1

Back in 2012 I wrote a snippet of code for delta timing in JavaScript, which uses setTimeout and has start and stop functions: https://gist.github.com/aaditmshah/2056987

See the demo:

var button = document.querySelector("button");
var div = document.querySelector("div");

var running = false;

var number = 1;

var timer = new DeltaTimer(function () {
  div.innerHTML = number++;
}, 1000);

button.addEventListener("click", function () {
  if (running) {
    timer.stop();
    button.innerHTML = "Start";
    running = false;
  } else {
    timer.start();
    button.innerHTML = "Stop";
    running = true;
  }
});

function DeltaTimer(render, interval) {
    var timeout;
    var lastTime;

    this.start = start;
    this.stop = stop;

    function start() {
        timeout = setTimeout(loop, 0);
        lastTime = Date.now();
        return lastTime;
    }

    function stop() {
        clearTimeout(timeout);
        return lastTime;
    }

    function loop() {
        var thisTime = Date.now();
        var deltaTime = thisTime - lastTime;
        var delay = Math.max(interval - deltaTime, 0);
        timeout = setTimeout(loop, delay);
        lastTime = thisTime + delay;
        render(thisTime);
    }
}

Start

Hope that helps.