import { Event } from '@zcomponent/core';
import * as THREE from 'three';
/**
 * A helper class to select objects in a scene.
 * Dragging the mouse will draw a selection box, selecting all objects that are
 * intersected by it.
 */
export declare class SelectionBoxHelper {
    private selectionBox?;
    private helper?;
    private renderer?;
    onSelected: Event<THREE.Mesh<THREE.BufferGeometry, THREE.Material | THREE.Material[]>[]>;
    enabled: boolean;
    private lastSelection;
    updateCurrentContext(camera: THREE.Camera, scene: THREE.Scene, renderer: THREE.WebGLRenderer): void;
    private normalizedDeviceCoordinates;
    private updateNormalizedDeviceCoordinates;
    onPointerDown: (event: MouseEvent) => void;
    onPointerMove: (event: MouseEvent) => void;
    private isSelectionChanged;
    dispose(): void;
}