Wrapper for requestAnimationFrame that accepts a callback and duration. Gives the callback a "completion" value between 0 and 1 every animation frame

gistfile1.js

var animateObject = function (callback, duration) {

    var startTime = 0;
    var slideFrame = function(animationMiliSeconds) {
        startTime = startTime || animationMiliSeconds;
        var timeTaken = animationMiliSeconds - startTime;

        var completion = timeTaken / duration;

        if (animationMiliSeconds <= startTime+duration) {
            callback(completion);
            requestAnimationFrame(slideFrame);
        } else {
            callback(1);
        }
    }
    requestAnimationFrame(slideFrame);
}