import { Object3D, Vector3 } from "three";
import { Behaviour } from "./Component.js";
/**
 * The [LookAtConstraint](https://engine.needle.tools/docs/api/LookAtConstraint) component is primarely used by {@link OrbitControls} to set the camera's focus point.
 * It does not have its own logic to update the look-at position.
 *
 * The constraint uses a list of source objects - the look-at target is
 * calculated from the first source in the `sources` array.
 *
 * **Integration with OrbitControls:**
 * When attached to the same GameObject as OrbitControls, this constraint
 * controls where the camera orbits around and looks at.
 *
 * @summary Look At Constraint for camera targeting
 * @category Camera and Controls
 * @group Components
 * @see {@link OrbitControls} for camera orbit controls
 * @see {@link SmoothFollow} for smooth position/rotation following
 * @see {@link LookAt} for directly making an object look at a target without using a constraint
 */
export declare class LookAtConstraint extends Behaviour {
    /**
     * When true, the constraint is active and affects the target.
     * Set to false to temporarily disable without removing sources.
     */
    constraintActive: boolean;
    /**
     * When true, the look-at position is locked and won't update
     * even if source objects move.
     */
    locked: boolean;
    /**
     * Objects to look at. The first object in the array is used
     * as the primary look-at target.
     */
    sources: Object3D[];
    /**
     * Sets the world position that the constraint should look at.
     * Updates the first source object's position.
     * @param worldPosition The world-space position to look at
     */
    setConstraintPosition(worldPosition: Vector3): void;
}
