/**
 * Handles asynchronous loading of assets like images.
 */
export default class ResourceLoader {
    /** Internal helper to access the global shared state. */
    private static get _state();
    private static get assets();
    private static get loadingQueue();
    private static get totalToLoad();
    private static set totalToLoad(value);
    private static get loadedCount();
    private static set loadedCount(value);
    /**
     * Queue an image for loading.
     * @param tag Unique tag to reference the image later.
     * @param src Path to the image file.
     */
    static queueImage(tag: string, src: string): void;
    /**
     * Start loading all queued assets.
     * @param onProgress Optional callback for loading progress updates.
     */
    static loadAll(onProgress?: (percent: number) => void): Promise<void>;
    /**
     * Get a loaded asset by its tag.
     * @param tag The tag used when queuing the asset.
     * @returns The loaded HTMLImageElement.
     */
    static getImage(tag: string): HTMLImageElement;
    /**
     * Returns all loaded assets.
     * @returns An array of { tag, image } objects.
     */
    static getLoadedAssets(): {
        tag: string;
        image: HTMLImageElement;
    }[];
    /**
     * Clears all loaded assets and the loading queue.
     */
    static clear(): void;
}