import { Extension, PropertyType, ReaderContext, Texture, WriterContext } from '@gltf-transform/core';
/**
 * NEEDLE_pmrem extension for gltf-transform.
 * Marks textures that have been pre-processed with PMREM (EXR → KTX2 HDR).
 * At write time, adds `NEEDLE_pmrem: { source: imageIndex }` to each marked texture
 * so the Needle Engine runtime can load them correctly with CubeUVReflectionMapping.
 */
export declare class NEEDLE_pmrem extends Extension {
    static readonly EXTENSION_NAME = "NEEDLE_pmrem";
    readonly extensionName = "NEEDLE_pmrem";
    /** Textures that were converted from EXR via PMREM */
    private readonly pmremTextures;
    /** Mark a texture as PMREM-converted */
    addTexture(texture: Texture): void;
    /** @hidden */
    preread(context: ReaderContext, _propertyType: PropertyType): this;
    /** @hidden */
    read(context: ReaderContext): this;
    /** @hidden */
    write(context: WriterContext): this;
}