import { Document } from '@gltf-transform/core';
export interface MergeLodsResult {
    document: Document;
    scenes: string[];
    texturesBefore: number;
    texturesAfter: number;
}
/**
 * Merges per-LOD GLBs into one multi-scene document: scene i = LOD level i (named `lodN`, document
 * order = level order), then dedup() collapses the byte-identical embedded images/materials the
 * per-LOD optimize runs each carried. Three.js GLTFLoader exposes the levels as gltf.scenes[i] and
 * its per-index caching shares one Texture/Material instance across levels — the runtime GPU dedupe
 * falls out of the file format, no runtime code. (C2 materials backlog items 1+4.)
 */
export declare function mergeLods(documents: Document[]): Promise<MergeLodsResult>;