source/sortable-helper.js
function (event, target, scrollableContainer) {
          var pos = {};
          pos.offsetX = event.pageX - this.offset(target, scrollableContainer).left;
          pos.offsetY = event.pageY - this.offset(target, scrollableContainer).top;
          pos.startX = pos.lastX = event.pageX;
          pos.startY = pos.lastY = event.pageY;
          pos.nowX = pos.nowY = pos.distX = pos.distY = pos.dirAx = 0;
          pos.dirX = pos.dirY = pos.lastDirX = pos.lastDirY = pos.distAxX = pos.distAxY = 0;
          return pos;
        }
function (event, target, scrollableContainer) {
          var pos = {};
          pos.offsetX = event.pageX - this.offset(target, scrollableContainer).left;
          pos.offsetY = event.pageY - this.offset(target, scrollableContainer).top;
          pos.startX = pos.lastX = event.pageX;
          pos.startY = pos.lastY = event.pageY;
          pos.nowX = pos.nowY = pos.distX = pos.distY = pos.dirAx = 0;
          pos.dirX = pos.dirY = pos.lastDirX = pos.lastDirY = pos.distAxX = pos.distAxY = 0;
          return pos;
        }
function ( event , target , scrollableContainer ) { var pos = { } ; pos . offsetX = event . pageX - this . offset ( target , scrollableContainer ) . left ; pos . offsetY = event . pageY - this . offset ( target , scrollableContainer ) . top ; pos . startX = pos . lastX = event . pageX ; pos . startY = pos . lastY = event . pageY ; pos . nowX = pos . nowY = pos . distX = pos . distY = pos . dirAx = 0 ; pos . dirX = pos . dirY = pos . lastDirX = pos . lastDirY = pos . distAxX = pos . distAxY = 0 ; return pos ; }
Get the start position of the target element according to the provided event properties.

@param {Object} event Event
@param {Object} target Target element
@param {Object} [scrollableContainer] (optional) Scrollable container object
@returns {Object} Object with properties offsetX, offsetY.
Get the start position of the target element according to the provided event properties .