Drop in replacements for setTimeout()/setInterval() that makes use of requestAnimationFrame() where possible for better performance

README

Drop in replace functions for setTimeout() & setInterval() that 
make use of requestAnimationFrame() for performance where available

requestAnimFrame.js

// requestAnimationFrame() shim by Paul Irish
// http://paulirish.com/2011/requestanimationframe-for-smart-animating/
window.requestAnimFrame = (function() {
    return  window.requestAnimationFrame ||
            window.webkitRequestAnimationFrame ||
            window.mozRequestAnimationFrame ||
            window.oRequestAnimationFrame ||
            window.msRequestAnimationFrame ||
            function(callback, element){
                window.setTimeout(callback, 16.667);
            };
})();

requestInterval.js

/**
 * Behaves the same as setInterval except uses requestAnimationFrame() where possible for better performance
 * @param {function} fn The callback function
 * @param {int} delay The delay in milliseconds
 */
window.requestInterval = function(fn, delay) {
    if (!window.requestAnimationFrame &&
        !window.webkitRequestAnimationFrame &&
        !window.mozRequestAnimationFrame &&
        !window.oRequestAnimationFrame &&
        !window.msRequestAnimationFrame) {
        return window.setInterval(fn, delay);
    }
    var start = new Date().getTime(),
        handle = {};

    function loop() {
        var current = new Date().getTime(),
            delta = current - start;

        if (delta >= delay) {
            fn.call();
            start = new Date().getTime();
        }
        handle.value = requestAnimFrame(loop);
    }
    handle.value = requestAnimFrame(loop);
    return handle;
};

/**
 * Behaves the same as clearInterval except uses cancelRequestAnimationFrame() where possible for better performance
 * @param {int|object} fn The callback function
 */
window.clearRequestInterval = function(handle) {
    window.cancelAnimationFrame ? window.cancelAnimationFrame(handle.value) :
    window.webkitCancelRequestAnimationFrame ? window.webkitCancelRequestAnimationFrame(handle.value) :
    window.mozCancelRequestAnimationFrame ? window.mozCancelRequestAnimationFrame(handle.value) :
    window.oCancelRequestAnimationFrame ? window.oCancelRequestAnimationFrame(handle.value) :
    window.msCancelRequestAnimationFrame ? msCancelRequestAnimationFrame(handle.value) :
    clearInterval(handle);
};

requestTimeout.js

/**
 * Behaves the same as setTimeout except uses requestAnimationFrame() where possible for better performance
 * @param {function} fn The callback function
 * @param {int} delay The delay in milliseconds
 */
window.requestTimeout = function(fn, delay) {
    if (!window.requestAnimationFrame &&
        !window.webkitRequestAnimationFrame &&
        !window.mozRequestAnimationFrame &&
        !window.oRequestAnimationFrame &&
        !window.msRequestAnimationFrame) {
        return window.setTimeout(fn, delay);
    }

    var start = new Date().getTime(),
        handle = {};
    
    function loop(){
        var current = new Date().getTime(),
            delta = current - start;
        if (delta >= delay) {
            fn.call();
        } else {
            handle.value = requestAnimFrame(loop);
        }
    }
    handle.value = requestAnimFrame(loop);
    return handle;
};

/**
 * Behaves the same as clearInterval except uses cancelRequestAnimationFrame() where possible for better performance
 * @param {int|object} fn The callback function
 */
window.clearRequestTimeout = function(handle) {
    window.cancelAnimationFrame ? window.cancelAnimationFrame(handle.value) :
    window.webkitCancelRequestAnimationFrame ? window.webkitCancelRequestAnimationFrame(handle.value) :
    window.mozCancelRequestAnimationFrame ? window.mozCancelRequestAnimationFrame(handle.value) :
    window.oCancelRequestAnimationFrame ? window.oCancelRequestAnimationFrame(handle.value) :
    window.msCancelRequestAnimationFrame ? msCancelRequestAnimationFrame(handle.value) :
    clearTimeout(handle);
};