/**
 * An infinite ray. Rays are commonly used for picking, raycasting and intersection tests.
 *
 * A ray is an {@link origin} and a {@link direction}. It performs no intersection itself: pass it
 * to the `intersectsRay` method of a {@link BoundingBox}, {@link BoundingSphere},
 * {@link OrientedBox}, {@link Plane} or {@link Tri}. Keep the direction normalized, as those tests
 * require it. The constructor copies the vectors it is given, and {@link set} updates both in
 * place.
 *
 * @example
 * // A ray from the camera through a screen position
 * const ray = new Ray();
 * entity.camera.screenToWorld(x, y, entity.camera.nearClip, ray.origin);
 * entity.camera.screenToWorld(x, y, entity.camera.farClip, ray.direction);
 * ray.direction.sub(ray.origin).normalize();
 * @category Math
 */
export class Ray {
    /**
     * Creates a new Ray instance. The ray is infinite, starting at a given origin and pointing in
     * a given direction.
     *
     * @param {Vec3} [origin] - The starting point of the ray. The constructor copies
     * this parameter. Defaults to the origin (0, 0, 0).
     * @param {Vec3} [direction] - The direction of the ray. The constructor copies
     * this parameter. Defaults to a direction down the world negative Z axis (0, 0, -1).
     * @example
     * // Create a new ray starting at the position of this entity and pointing down
     * // the entity's negative Z axis
     * const ray = new Ray(this.entity.getPosition(), this.entity.forward);
     */
    constructor(origin?: Vec3, direction?: Vec3);
    /**
     * The starting point of the ray.
     *
     * @readonly
     * @type {Vec3}
     */
    readonly origin: Vec3;
    /**
     * The direction of the ray.
     *
     * @readonly
     * @type {Vec3}
     */
    readonly direction: Vec3;
    /**
     * Sets origin and direction to the supplied vector values.
     *
     * @param {Vec3} origin - The starting point of the ray.
     * @param {Vec3} direction - The direction of the ray.
     * @returns {Ray} Self for chaining.
     */
    set(origin: Vec3, direction: Vec3): Ray;
    /**
     * Copies the contents of a source Ray.
     *
     * @param {Ray} src - The Ray to copy from.
     * @returns {Ray} Self for chaining.
     */
    copy(src: Ray): Ray;
    /**
     * Returns a clone of the Ray.
     *
     * @returns {this} A duplicate Ray.
     */
    clone(): this;
}
import { Vec3 } from '../math/vec3.js';