import type { Viewport } from "./viewport";
export type VisibilityWalkInit = {
    element: HTMLElement;
    win: Window;
    doc: Document;
    viewport: Viewport;
    opacity: boolean;
    useCache: boolean;
};
export declare class VisibilityWalk {
    private readonly chain;
    private transparent;
    private scroller;
    private innerBox;
    private prevBox;
    private readonly element;
    private readonly win;
    private readonly doc;
    private readonly viewport;
    private readonly opacity;
    private readonly useCache;
    private readonly ownRect;
    constructor({ element, win, doc, viewport, opacity, useCache }: VisibilityWalkInit);
    private anchor;
    private satisfies;
    private visit;
    private unvisit;
    private registerScroller;
    private registerBox;
    private clearBox;
    private trustCache;
    private classify;
    evaluate(): boolean;
    get coverage(): HTMLElement[];
    get hiddenByOpacity(): boolean;
}