You can simply store the easing function in $.easing
:
$.easing.easeOutBack = function(x, t, b, c, d, s) {
if(s == undefined) s = 1.70158;
return c * ((t = t / d - 1) * t * ((s + 1) * t + s) + 1) + b;
};
After that you can use it just like you would do when the easing plugin is loaded.
Passing the function directly doesn't work because jQuery's animate()
only accepts a string for the easing function (which is looked up in $.easing
).