function Overlap$1(params) {
    Transform.call(this, null, params);
  }
Analyze items for overlap, changing opacity to hide items with
overlapping bounding boxes. This transform will preserve at least
two items (e.g., first and last) even if overlap persists.
@param {object} params - The parameters for this operator.
@param {function(*,*): number} [params.sort] - A comparator
  function for sorting items.
@param {object} [params.method] - The overlap removal method to apply.
  One of 'parity' (default, hide every other item until there is no
  more overlap) or 'greedy' (sequentially scan and hide and items that
  overlap with the last visible item).
@param {object} [params.boundScale] - A scale whose range should be used
  to bound the items. Items exceeding the bounds of the scale range
  will be treated as overlapping. If null or undefined, no bounds check
  will be applied.
@param {object} [params.boundOrient] - The orientation of the scale
  (top, bottom, left, or right) used to bound items. This parameter is
  ignored if boundScale is null or undefined.
@param {object} [params.boundTolerance] - The tolerance in pixels for
  bound inclusion testing (default 1). This specifies by how many pixels
  an item's bounds may exceed the scale range bounds and not be culled.
@constructor