import { type ITextureInfo, type IMaterialPbrMetallicRoughness } from "babylonjs-gltf2interface";
import { type Nullable } from "@babylonjs/core/types.js";
import { type BaseTexture } from "@babylonjs/core/Materials/Textures/baseTexture.js";
import { type GLTFExporter } from "./glTFExporter.js";
import { type StandardMaterial } from "@babylonjs/core/Materials/standardMaterial.js";
import { PBRBaseMaterial } from "@babylonjs/core/Materials/PBR/pbrBaseMaterial.js";
import { OpenPBRMaterial } from "@babylonjs/core/Materials/PBR/openpbrMaterial.js";
/**
 * Computes the metallic factor from specular glossiness values.
 * @param diffuse diffused value
 * @param specular specular value
 * @param oneMinusSpecularStrength one minus the specular strength
 * @returns metallic value
 * @internal
 */
export declare function _SolveMetallic(diffuse: number, specular: number, oneMinusSpecularStrength: number): number;
/**
 * Computes the metallic/roughness factors from a Standard Material.
 * @internal
 */
export declare function _ConvertToGLTFPBRMetallicRoughness(babylonStandardMaterial: StandardMaterial): IMaterialPbrMetallicRoughness;
/**
 * Utility methods for working with glTF material conversion properties.
 * @internal
 */
export declare class GLTFMaterialExporter {
    private readonly _exporter;
    private _textureMap;
    private _internalTextureToImage;
    constructor(_exporter: GLTFExporter);
    getTextureInfo(babylonTexture: Nullable<BaseTexture>): Nullable<ITextureInfo>;
    exportStandardMaterialAsync(babylonStandardMaterial: StandardMaterial, hasUVs: boolean): Promise<number>;
    private _finishMaterialAsync;
    /**
     * Resizes the two source textures to the same dimensions.  If a texture is null, a default white texture is generated.  If both textures are null, returns null
     * @param texture1 first texture to resize
     * @param texture2 second texture to resize
     * @param scene babylonjs scene
     * @returns resized textures or null
     */
    private _resizeTexturesToSameDimensions;
    /**
     * Convert Specular Glossiness Textures to Metallic Roughness
     * See link below for info on the material conversions from PBR Metallic/Roughness and Specular/Glossiness
     * @see https://github.com/KhronosGroup/glTF/blob/main/extensions/2.0/Archived/KHR_materials_pbrSpecularGlossiness/examples/convert-between-workflows-.js/babylon.pbrUtilities.js
     * @param diffuseTexture texture used to store diffuse information
     * @param specularGlossinessTexture texture used to store specular and glossiness information
     * @param factors specular glossiness material factors
     * @returns pbr metallic roughness interface or null
     */
    private _convertSpecularGlossinessTexturesToMetallicRoughnessAsync;
    /**
     * Converts specular glossiness material properties to metallic roughness
     * @param specularGlossiness interface with specular glossiness material properties
     * @returns interface with metallic roughness material properties
     */
    private _convertSpecularGlossinessToMetallicRoughness;
    /**
     * Calculates the surface reflectance, independent of lighting conditions
     * @param color Color source to calculate brightness from
     * @returns number representing the perceived brightness, or zero if color is undefined
     */
    private _getPerceivedBrightness;
    /**
     * Returns the maximum color component value
     * @param color
     * @returns maximum color component value, or zero if color is null or undefined
     */
    private _getMaxComponent;
    /**
     * Convert a PBRMaterial (Metallic/Roughness) to Metallic Roughness factors
     * @param baseColor Base color of the material
     * @param metallic Metallic factor of the material
     * @param roughness Roughness factor of the material
     * @param albedoTexture Albedo texture of the material
     * @param metallicTexture Metallic texture of the material
     * @param roughnessTexture Roughness texture of the material
     * @param babylonPBRMaterial BJS PBR Metallic Roughness Material
     * @param glTFPbrMetallicRoughness glTF PBR Metallic Roughness interface
     * @param hasUVs specifies if texture coordinates are present on the submesh to determine if textures should be applied
     * @returns glTF PBR Metallic Roughness factors
     */
    private _convertMetalRoughFactorsToMetallicRoughnessAsync;
    private _getTextureSampler;
    private _getGLTFTextureWrapMode;
    /**
     * Convert a PBRMaterial (Specular/Glossiness) to Metallic Roughness factors
     * @param babylonPBRMaterial BJS PBR Metallic Roughness Material
     * @param pbrMetallicRoughness glTF PBR Metallic Roughness interface
     * @param hasUVs specifies if texture coordinates are present on the submesh to determine if textures should be applied
     * @returns glTF PBR Metallic Roughness factors
     */
    private _convertSpecGlossFactorsToMetallicRoughnessAsync;
    exportPBRMaterialAsync(babylonPBRMaterial: PBRBaseMaterial, hasUVs: boolean): Promise<number>;
    private _setMetallicRoughnessPbrMaterialAsync;
    exportOpenPBRMaterialAsync(babylonOpenPBRMaterial: OpenPBRMaterial, hasUVs: boolean): Promise<number>;
    exportTextureAsync(babylonTexture: BaseTexture, overrideId?: Nullable<number>): Promise<Nullable<ITextureInfo>>;
    private _exportTextureImageAsync;
    private _exportImageAsync;
    private _exportTextureInfo;
    private _exportTextureSampler;
}