code: function matchType(pointerType, ev) {
      if(!ev.pointerType) {
        return false;
      }
  
      var pt = ev.pointerType
        , types = {};
  
      types[POINTER_MOUSE] = (pt === POINTER_MOUSE);
      types[POINTER_TOUCH] = (pt === POINTER_TOUCH);
      types[POINTER_PEN] = (pt === POINTER_PEN);
      return types[pointerType];
    }
docs: check if ev matches pointertype
  @param   {String}        pointerType     POINTER_MOUSE
  @param   {PointerEvent}  ev