/**
 * 2D bounding box defined as [xmin, ymin, xmax, ymax].
 */
export type BoundingBox2D = [number, number, number, number];
/**
 * Returns the bounding box encompassing both boxes.
 * @param box1 first box.
 * @param box2 second box.
 * @param defaultBox in case both boxes are undefined.
 * @returns the bounding box encompassing both boxes.
 */
export declare const boxUnion: (box1: BoundingBox2D | undefined, box2: BoundingBox2D | undefined, defaultBox?: BoundingBox2D) => BoundingBox2D;
/**
 * 3D point defined as [x, y].
 */
export type Point2D = [number, number];
/**
 * Returns the center of the bounding box.
 * @param box1 bounding box.
 * @returns the center of the bounding box.
 */
export declare const boxCenter: (box: BoundingBox2D) => Point2D;
/**
 * Returns true if the bounding box is not empty.
 * @param box1 bounding box.
 * @returns true if the bounding box is not empty.
 */
export declare const isEmpty: (box: BoundingBox2D | undefined) => boolean;
