import { RenderManagerBase } from './RenderManagerBase';
/**
 * Displays temporary hint messages in the viewer with optional fade-out animation.
 */
export declare class PromptTools {
    private renderManager;
    private messageContainer;
    private readonly viewerElement;
    private message;
    private currentTween;
    private tweenGroup;
    /**
     * @param renderManager - {@link RenderManagerBase} instance.
     * @param viewerElement - viewer HTML element.
     */
    constructor(renderManager: RenderManagerBase, viewerElement: HTMLElement);
    private updateMessageContainer;
    /**
     * Display a temporary hint message in the viewer.
     * @param message - Message text. Pass empty string to hide.
     * @param timeout - If > 0, the message fades out after this many milliseconds.
     */
    setMessage(message?: string, timeout?: number): this;
    /** Remove the prompt DOM element and stop any running tween. */
    dispose(): void;
    update(deltaTime?: number): void;
}