.scrollProxy

Number - A special object that gets created for type: "scroll" (or scrollTop or scrollLeft) Draggables. This object manages the scrolling behavior, applying the necessary transforms or margins to accomplish overscrolling when necessary. The scrollProxy object has a top() and left() getter and setter methods (and scrollTop() and scrollLeft() which are simply the inverse of top() and left()). If you need to get the scrolling velocity, make sure you’ve loaded ThrowPropsPlugin and set throwProps: true on the Draggable and then you can use ThrowPropsPlugin.getVelocity(yourDraggable.scrollProxy, "top") to get the vertical scrolling velocity (use "left" for horizontal).