import { ViewportMetrics } from '../../shared/models';
/**
 * Calculates the visibility ratio of an element in the viewport
 * @param element - The HTML element to check
 * @returns A number between 0 and 1 representing the visible percentage
 */
export declare function calculateElementVisibilityRatio(element: HTMLElement): number;
/**
 * Calculates the offset percentage of an element from the top of the viewport
 * @param element - The HTML element to check
 * @returns Percentage value (can be negative if above viewport)
 */
export declare function calculateViewportOffset(element: HTMLElement): number;
/**
 * Checks if an element meets a specific visibility threshold
 * @param element - The HTML element to check
 * @param threshold - The required visibility ratio (0.0 to 1.0)
 * @returns True if the element meets or exceeds the threshold
 */
export declare function isElementMeetingVisibilityThreshold(element: HTMLElement, threshold: number): boolean;
/**
 * Gets comprehensive viewport metrics for an element
 * @param element - The HTML element to analyze
 * @returns Object containing offset percentage and visibility ratio
 */
export declare function getViewportMetrics(element: HTMLElement): ViewportMetrics;