nl_tokens: TODO what happens if a transition is aborted? TODO use this with Animation to dedupe some code?
pl_tokens: function ( options ) { var easing ; this . duration = options . duration ; this . step = options . step ; this . complete = options . <mask> ; // easing if ( typeof options . easing === 'string' ) { easing = options . root . easing [ options . easing ] ; if ( ! easing ) { warn ( 'Missing easing function ("' + options . easing + '"). You may need to download a plugin from [TODO]' ) ; easing = linear ; } } else if ( typeof options . easing === 'function' ) { easing = options . easing ; } else { easing = linear ; } this . easing = easing ; this . start = getTime ( ) ; this . end = this . start + this . duration ; this . running = true ; animations . add ( this ) ; }